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Sample records for generating sludge combustion

  1. ABB Combustion Engineering approach to steam generator sludge lancing

    Energy Technology Data Exchange (ETDEWEB)

    Estes, G.T. [ABB CE, Chattanooga, TN (United States)

    1994-12-31

    During the normal operation of a recirculating steam generator, insoluble corrosion products, commonly called {open_quotes}sludge,{close_quotes} are formed. Sludge accumulates on the tube sheet, heat transfer tubes, support plates, and other surfaces. It can be expected that corrosion products will continue to build up even with rigid secondary water chemistry controls. This corrosion product buildup directly affects thermal efficiency, resulting in megawatt and pressure loss. Secondary-side corrosion causes an increase in tubes that require plugging or sleeving. More importantly, corrosion product buildup has caused forced outages and steam-generator replacements. One plant has permanently shut down due to steam-generator secondary-side corrosion. This report describes a process for sludge removal.

  2. Pressurized Fluidized Bed Combustion of Sewage Sludge

    Science.gov (United States)

    Suzuki, Yoshizo; Nojima, Tomoyuki; Kakuta, Akihiko; Moritomi, Hiroshi

    A conceptual design of an energy recovering system from sewage sludge was proposed. This system consists of a pressurized fluidized bed combustor, a gas turbine, and a heat exchanger for preheating of combustion air. Thermal efficiency was estimated roughly as 10-25%. In order to know the combustion characteristics of the sewage sludge under the elevated pressure condition, combustion tests of the dry and wet sewage sludge were carried out by using laboratory scale pressurized fluidized bed combustors. Combustibility of the sewage sludge was good enough and almost complete combustion was achieved in the combustion of the actual wet sludge. CO emission and NOx emission were marvelously low especially during the combustion of wet sewage sludge regardless of high volatile and nitrogen content of the sewage sludge. However, nitrous oxide (N2O) emission was very high. Hence, almost all nitrogen oxides were emitted as the form of N2O. From these combustion tests, we judged combustion of the sewage sludge with the pressurized fluidized bed combustor is suitable, and the conceptual design of the power generation system is available.

  3. Combustion characteristics of biodried sewage sludge.

    Science.gov (United States)

    Hao, Zongdi; Yang, Benqin; Jahng, Deokjin

    2018-02-01

    In this study, effects of biodrying on the characteristics of sewage sludge and the subsequent combustion behavior were investigated. 7-Day of biodrying removed 49.78% of water and 23.17% of VS initially contained in the sewage sludge and increased lower heating value (LHV) by 37.87%. Meanwhile, mass contents of C and N decreased from 36.25% and 6.12% to 32.06% and 4.82%, respectively. Surface of the biodried sewage sludge (BDSS) appeared granulated and multi-porous, which was thought to facilitate air transfer during combustion. According to thermogravimetric (TG) analysis coupled with mass spectrometer (MS) with a heating rate of 10 °C/min from 35 °C to 1000 °C, thermally-dried sewage sludge (TDSS) and BDSS lost 74.39% and 67.04% of the initial mass, respectively. In addition, combustibility index (S) of BDSS (8.67 × 10 -8  min -2  K -3 ) was higher than TDSS. TG-MS analyses also showed that less nitrogenous gases were generated from BDSS than TDSS. It was again showed that the average CO and NO concentrations in exit gas from isothermal combustion of BDSS were lower than those from TDSS, especially at low temperatures (≤800 °C). Based on these results, it was concluded that biodrying of sewage sludge was an energy-efficient water-removal method with less emission of air pollutants when BDSS was combusted. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Resuspension of coal and coal/municipal sewage sludge combustion generated fine particles for inhalation health effects studies

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Art; Wendt, Jost O.L. [Department of Chemical and Environmental Engineering, University of Arizona, 85721 Tucson, AZ (United States); Cenni, Roberta [Institut fuer Verfahrenstechnik und Dampfkesselwesen, Universitaet Stuttgart, Stuttgart (Germany); Young, R. Scott; Witten, Mark L. [Lung Injury Laboratory, Department of Pediatrics, Arizona Health Sciences Center, 85721 Tucson, AZ (United States)

    2002-03-27

    Airborne particulate matter (PM) is an important environmental issue because of its association with acute respiratory distress in humans, although the specific particle characteristics that cause lung damage have yet to be identified. Particle size, acid aerosols, water-soluble transition metals (e.g. Cu, Fe, V, Ni and Zn), polyaromatic hydrocarbons, and particle composition are the focus of several popular hypotheses addressing respiratory distress. All of the above mentioned characteristics are contained in PM generated from the combustion of both pulverized coal, and biomass, including dried municipal sewage sludge (MSS). In this investigation, we report results from collaborative interdisciplinary research on the inhalation health risks caused by particles emitted from the co-combustion of municipal sewage sludge (MSS) and coal. A solid particle resuspension system was implemented to resuspend ash particles. Mice were exposed to resuspended coal and MSS/coal ash particles. Mice exposed to MSS/coal ash particulate demonstrated significant increases in lung permeability, a marker of the early stages of pathological lung injury, while the mice exposed to coal-only ash did not. These results show that the composition of particles actually inhaled is important in determining lung damage. Zinc was significantly more concentrated in the MSS/coal ash than coal ash particles and the pH of these particles did not differ significantly. Specifically, an MSS/coal mixture, when burned, emits particles that may cause significantly more lung damage than coal alone, and that consequently, the use of MSS as a 'green', CO{sub 2}-neutral replacement fuel should be carefully considered.

  5. Consequences of sludge composition on combustion performance derived from thermogravimetry analysis

    International Nuclear Information System (INIS)

    Li, Meiyan; Xiao, Benyi; Wang, Xu; Liu, Junxin

    2015-01-01

    Highlights: • Volatiles, particularly proteins, play a key role in sludge combustion. • Sludge combustion performance varies with different sludge organic concentrations. • Carbohydrates significantly affect the combustion rate in the second stage. • Combustion performance of digested sludge is more negative compared with others. - Abstract: Wastewater treatment plants produce millions of tons of sewage sludge. Sewage sludge is recognized as a promising feedstock for power generation via combustion and can be used for energy crisis adaption. We aimed to investigate the quantitative effects of various sludge characteristics on the overall sludge combustion process performance. Different types of sewage sludge were derived from numerous wastewater treatment plants in Beijing for further thermogravimetric analysis. Thermogravimetric–differential thermogravimetric curves were used to compare the performance of the studied samples. Proximate analytical data, organic compositions, elementary composition, and calorific value of the samples were determined. The relationship between combustion performance and sludge composition was also investigated. Results showed that the performance of sludge combustion was significantly affected by the concentration of protein, which is the main component of volatiles. Carbohydrates and lipids were not correlated with combustion performance, unlike protein. Overall, combustion performance varied with different sludge organic composition. The combustion rate of carbohydrates was higher than those of protein and lipid, and carbohydrate weight loss mainly occurred during the second stage (175–300 °C). Carbohydrates have a substantial effect on the rate of system combustion during the second stage considering the specific combustion feature. Additionally, the combustion performance of digested sewage sludge is more negative than the others

  6. Steam generator sludge removal apparatus

    International Nuclear Information System (INIS)

    Schafer, B.W.; Werner, C.E.; Klahn, F.C.

    1992-01-01

    The present invention relates to equipment for cleaning steam generators and in particular to a high pressure fluid lance for cleaning sludge off the steam generator tubes away from an open tube lane. 6 figs

  7. Gaseous emissions from sewage sludge combustion in a moving bed combustor.

    Science.gov (United States)

    Batistella, Luciane; Silva, Valdemar; Suzin, Renato C; Virmond, Elaine; Althoff, Chrtistine A; Moreira, Regina F P M; José, Humberto J

    2015-12-01

    Substantial increase in sewage sludge generation in recent years requires suitable destination for this residue. This study evaluated the gaseous emissions generated during combustion of an aerobic sewage sludge in a pilot scale moving bed reactor. To utilize the heat generated during combustion, the exhaust gas was applied to the raw sludge drying process. The gaseous emissions were analyzed both after the combustion and drying steps. The results of the sewage sludge characterization showed the energy potential of this residue (LHV equal to 14.5 MJ kg(-1), db) and low concentration of metals, polycyclic aromatic hydrocarbons (PAH), polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF). The concentration of CO, NOx, BTEX (benzene, toluene, ethylbenzene and xylenes) emitted from the sludge combustion process were lower than the legal limits. The overall sludge combustion and drying process showed low emissions of PCDD/PCDF (0.42 ng I-TEQ N m(-3)). BTEX and PAH emissions were not detected. Even with the high nitrogen concentration in the raw feed (5.88% db), the sludge combustion process presented NOx emissions below the legal limit, which results from the combination of appropriate feed rate (A/F ratio), excess air, and mainly the low temperature kept inside the combustion chamber. It was found that the level of CO emissions from the overall sludge process depends on the dryer operating conditions, such as the oxygen content and the drying temperature, which have to be controlled throughout the process in order to achieve low CO levels. The aerobic sewage sludge combustion process generated high SO2 concentration due to the high sulfur content (0.67 wt%, db) and low calcium concentration (22.99 g kg(-1)) found in the sludge. The high concentration of SO2 in the flue gas (4776.77 mg N m(-3)) is the main factor inhibiting PCDD/PCDF formation. Further changes are needed in the pilot plant scheme to reduce SO2 and particulate matter emissions

  8. Environmental considerations on the FBC combustion of dry sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M. Helena; Abelha, Pedro; Gulyurtlu, Ibrahim; Cabrita, Isabel [INETI/DEECA, Lisboa (Portugal)

    2001-07-01

    This paper presents results of on-going research on the incineration of pre-dried granular sewage sludges using a FBC system. Co-combustion is compared with mono-combustion of sludges leads to minor emissions and higher retention of Cd, Pb, Cu, and Zn in the bottom ashes, when compared to co-combustion with coal. The leachability of the sludge is reduced through combustion, as none of the metals, Cd, Cr, Ca Ni, Ph, Zn, Co and Mn were leached from the bottom ashes. These findings may contribute to an improvement in the incineration of sewage sludges and to the development of applications for the ashes in civil engineering activities.

  9. Mechanisms and kinetics of granulated sewage sludge combustion.

    Science.gov (United States)

    Kijo-Kleczkowska, Agnieszka; Środa, Katarzyna; Kosowska-Golachowska, Monika; Musiał, Tomasz; Wolski, Krzysztof

    2015-12-01

    This paper investigates sewage sludge disposal methods with particular emphasis on combustion as the priority disposal method. Sewage sludge incineration is an attractive option because it minimizes odour, significantly reduces the volume of the starting material and thermally destroys organic and toxic components of the off pads. Additionally, it is possible that ashes could be used. Currently, as many as 11 plants use sewage sludge as fuel in Poland; thus, this technology must be further developed in Poland while considering the benefits of co-combustion with other fuels. This paper presents the results of experimental studies aimed at determining the mechanisms (defining the fuel combustion region by studying the effects of process parameters, including the size of the fuel sample, temperature in the combustion chamber and air velocity, on combustion) and kinetics (measurement of fuel temperature and mass changes) of fuel combustion in an air stream under different thermal conditions and flow rates. The combustion of the sludge samples during air flow between temperatures of 800 and 900°C is a kinetic-diffusion process. This process determines the sample size, temperature of its environment, and air velocity. The adopted process parameters, the time and ignition temperature of the fuel by volatiles, combustion time of the volatiles, time to reach the maximum temperature of the fuel surface, maximum temperature of the fuel surface, char combustion time, and the total process time, had significant impacts. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Heavy metals behaviour during mono-combustion and co-combustion of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M. Helena; Abelha, Pedro; Olieveira, J.F. Santos; Gulyurtlu, Ibrahim; Cabrita, Isabel [INETI-DEECA, Lisboa (Portugal)

    2005-03-01

    This paper presents the study of the combustion of granular dry sewage sludge performed on a pilot fluidized bed system. The results of mono-combustion of sludge and co-combustion with coal were compared with those of coal combustion for ash partitioning, the formation of gaseous pollutants and heavy metals behaviour. It was found that the mineral matter of sludge was essentially retained as bottom ashes. The production of fines ashes was small during the mono-combustion due to the tendency of coal to produce fine ashes which also contained unburned char. The degree of heavy metal volatilization was found to be slightly higher during co-combustion than in mono-combustion; however, most of them were retained in ashes and their emissions were found to be below the regulated levels. Hg was completely volatilized; however, during combustion trials involving coal it was captured by cyclone ashes at temperatures below 300 deg C. During sludge mono-combustion the retention of Hg in cyclone ashes containing low LOI was not enough to decrease emissions below the regulated levels; hence, it is necessary to install dedicated flue gas treatment for Hg removal. The leachability and ecotoxicity of sludge and ashes was compared with the new regulatory limits for landfill disposal in the EU. It was found that the release of organic matter and heavy metals found in the sludge was low from granular bed ashes; hence, except for sulphate release, bed ashes were converted into inert and non-ecotoxic materials. Ashes from test with limestone and cyclone ashes seemed to be more problematic because of pH effects and contamination with steel corrosion products. The recovery and reutilization of sludge bed ashes could, therefore, be possible, as long as the release of sulphate do not interfere with the process.

  11. Sludge combustion in fluidized bed reactors at laboratory scale

    International Nuclear Information System (INIS)

    Chirone, R.; Cammarota, A.

    2001-01-01

    The combustion of a dried sewage sludge in laboratory scale fluidized bed has been studied in Naples by the Istituto di ricerche sulla combustione (Irc) in the framework of a National project named Thermal Process with Energy Recovery to be used in laboratory and pre-pilot scale apparatus. The attention has been focused on emissions of unreacted carbon as elutriated fines, on the emissions of pollutant gases and on the assessment of the inventory of fly- and bottom ashes. The combustion behaviour of sewage sludge has been compared with those of a market available Tyre Derived Fuel (TDF) and a biomass from Mediterranean area (Robinia Pseudoacacia) and with that of a South African bituminous coal. Stationary combustion tests were carried out at 850 0 C by feeding particles in the size range 0-1 mm into a bed of silica sand without any sorbent addition. The fluidized bed combustor has been operated, at a superficial gas velocity of 0.4 m/s and different excesses of air ranging between 14 and 98%. Relatively high combustion efficiency, larger than 98.9% has been obtained in experiments carried out with sewage sludge and excess of air larger than 20%. These values, are comparable with those obtained in previously experimental activity carried out under similar operative conditions with a South Africa Bituminous coal (97-98%). It is larger than those obtained by using a Tyre Derived Fuel (89-90%) and the Robinia Pseudoacacia Biomass (93-93%). The relative importance of carbon fines elutriation, CO emissions and volatile bypassing the bed in determining the loss of combustion efficiency has been evaluated for the different fuels tested [it

  12. Co-combustion of sewage sludge; Mitverbrennung von Klaerschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Thome-Kozmiensky, K.J. [Technische Univ. Berlin (Germany). Fachgebiet Abfallwirtschaft

    1998-09-01

    Thermal sewage disposal pursues the following aims: destruction of organic pollutants contained in the sludge; concentration and removal or almost complete fixation of inorganic pollutants in the residue matrix; minimisation of the mass solid residue; production of useful products; utilisation of the caloric content. The thermal treatment chain should be as short as possible; intermediate stages in separate reactors such as digestion, drying, degasification or gasification should be avoided if the material is ultimately to be combusted. The present paper examines and assesses the co-combustion of sewage sludge. [Deutsch] Mit der thermischen Klaerschlammentsorgung werden folgende Ziele verfolgt: - Zerstoerung der im Schlamm enthaltenen organischen Schadstoffe, - Konzentration und Ausschleusung oder weitestgehende Fixierung der anorganischen Schadstoffe in die Reststoffmatrix, - Minimierung der Masse an festen Restabfaellen, - Herstellung verwertbarer Produkte, - Nutzung des Waermeeinhalts. Die thermische Behandlungskette sollte moeglichst kurz sein; Zwischenschritte wie Faulung, Trocknung, Ent- oder Vergasung in getrennten Reaktoren sollten vermieden werden, wenn letztendlich doch verbrannt wird. Das Verfahren der Mitverbrennung von Klaerschlamm wird hier untersucht und bewertet. (orig./SR)

  13. Co-combustion of tannery sludge in a commercial circulating fluidized bed boiler.

    Science.gov (United States)

    Dong, Hao; Jiang, Xuguang; Lv, Guojun; Chi, Yong; Yan, Jianhua

    2015-12-01

    Co-combusting hazardous wastes in existing fluidized bed combustors is an alternative to hazardous waste treatment facilities, in shortage in China. Tannery sludge is a kind of hazardous waste, considered fit for co-combusting with coal in fluidized bedboilers. In this work, co-combustion tests of tannery sludge and bituminous coal were conducted in a power plant in Jiaxing, Zhejiang province. Before that, the combustion behavior of tannery sludge and bituminous were studied by thermogravimetric analysis. Tannery sludge presented higher reactivity than bituminous coal. During the co-combustion tests, the emissions of harmful gases were monitored. The results showed that the pollutant emissions met the Chinese standard except for NOx. The Concentrations of seven trace elements (As, Cr, Cd, Ni, Cu, Pb, Mn) in three exit ash flows (bottom ash in bed, fly ash in filter, and submicrometer aerosol in flue gas) were analyzed. The results of mono-combustion of bituminous coal were compared with those of co-combustion with tannery sludge. It was found that chromium enriched in fly ash. At last, the leachability of fly ash and bottom ash was analyzed. The results showed that most species were almost equal to or below the limits except for As in bottom ashes and Cr in the fly ash of co-combustion test. The concentrations of Cr in leachates of co-combustion ashes are markedly higher than that of coal mono-combustion ashes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Combustion of crude oil sludge containing naturally occurring radioactive material

    International Nuclear Information System (INIS)

    Mohamad Puad Abu; Muhd Noor Muhd Yunus; Shamsuddin, A.H.; Sopian, K.

    2000-01-01

    The characteristics of crude oil sludge fi-om the crude oil terminal are very unique because it contains both heavy metals and also Naturally Occurring Radioactive Material (NORM). As a result, the Department of Environmental (DOE) and the Atomic Energy Licensing Board (AELB) considered it as Scheduled Wastes and Low Level Radioactive Waste (LLRW) respectively. As a Scheduled Wastes, there is no problem in dealing with the disposal of it since there already exist a National Center in Bukit Nanas to deal with this type of waste. However, the Center could not manage this waste due to the presence of NORM by which the policy regarding the disposal of this kind of waste has not been well established. This situation is unclear to certain parties, especially with respect to the relevant authorities having final jurisdiction over the issue as well as the best practical method of disposal of this kind of waste. Existing methods of treatment viewed both from literature and current practice include that of land farming, storing in plastic drum, re-injection into abandoned oil well, recovery, etc., found some problems. Due to its organic nature, very low level in radioactivity and the existence of a Scheduled Waste incineration facility in Bukit Nanas, there is a potential to treat this sludge by using thermal treatment technology. However, prior to having this suggestion to be put into practice, there are issues that need to be addressed. This paper attempts to discuss the potentials and the related issues of combusting crude oil sludge based on existing experimental data as well as mathematical modeling

  15. Thermogravimetric analysis of co-combustion between microalgae and textile dyeing sludge.

    Science.gov (United States)

    Peng, Xiaowei; Ma, Xiaoqian; Xu, Zhibin

    2015-03-01

    The synergistic interaction and kinetics of microalgae, textile dyeing sludge and their blends were investigated under combustion condition by thermogravimetric analysis. The textile dyeing sludge was blended with microalgae in the range of 10-90wt.% to investigate their co-combustion behavior. Results showed that the synergistic interaction between microalgae and textile dyeing sludge improved the char catalytic effect and alkali metals melt-induced effect on the decomposition of textile dyeing sludge residue at high temperature of 530-800°C. As the heating rate increasing, the entire combustion process was delayed but the combustion intensity was enhanced. The lowest average activation energy was obtained when the percentage of microalgae was 60%, which was 227.1kJ/mol by OFW and 227.4kJ/mol by KAS, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Gas Generation from K East Basin Sludges - Series II Testing

    International Nuclear Information System (INIS)

    Bryan, Samuel A.; Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R.; Thornton, Brenda M.

    2001-01-01

    This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor, pit and canister sludge. Mixed and unmixed and fractionated KE canister sludge were tested, along with floor and pit sludges from areas in the KE Basin not previously sampled. The first report in this series focused on gas generation from KE floor and canister sludge collected using a consolidated sampling technique. The third report will present results of gas generation testing of irradiated uranium fuel fragments with and without sludge addition. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge

  17. Environmental evaluation of sewage sludge co-combustion in a pilot FBC

    Energy Technology Data Exchange (ETDEWEB)

    M. Helena Lopes; P. Abelha; I. Cabrita; J.F.Santos Oliveira; I. Gulyurtlu [INETI/DEECA, Lisbon (Portugal)

    2003-07-01

    This paper presents a comparison of combustion of coal alone with that of a mixture of coal with sewage sludge with respect to flue gas emissions, the behaviour of heavy metals and potential environmental consequences of disposal of ashes produced. Co-combustion with sludge did not result in greater NOx, SO{sub 2}, HCl and CO emissions and the use of air staging and the addition of limestone proved to be effective to reduce NOx and SO{sub 2}. The mixing of sludge gave rise to an increase in amounts of heavy metals released, especially for Cd, Pb and Hg. However, as they were associated with particles greater than 1 {micro}m, the application of efficient flue gas treatment devices could decrease their emissions to the atmosphere. Metals were essentially retained in ashes captured in the bed and in the cyclones and most of the Hg was adsorbed in fly ashes that contained unburned carbon. The leachability of metals and organic matter present in the sludge decreased with combustion. The evaluation of the acid neutralization capacity (ANC) showed that ashes became more resistant to acidification than the parent sludge. Globally, this study concludes that the implication of the combustion of sludge is that it can reduce the negative impact on the environment compared with the traditional direct use of sludge in soils. 22 refs., 4 figs., 5 tabs.

  18. Heavy metals behavior during monocombustion and co-combustion of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M.H.; Abelha, P.; Oliveira, J.F.S.; Cabrita, I.; Gulyurtlu, I. [DEECA, INETI, Lisbon (Portugal)

    2005-04-01

    This paper presents the study of the combustion of granular dry sewage sludge performed on a pilot fluidized bed system. The results of monocombustion of sludge and co-combustion with coal were compared with those of coal combustion for ash partitioning, the formation of gaseous pollutants, and heavy metals behavior. It was found that the mineral matter of sludge was essentially retained as bottom ash. The production of fine ash was small during the monocombustion but was high during co-combustion due to the tendency of coal to produce fine ash, which also contained unburned char. The degree of heavy metal volatilization was found to be slightly higher during co-combustion than in monocombustion; however, most of the metals were retained in the ash and their emissions were found to be below the regulated levels. Hg was completely volatilized. However, during combustion trials involving coal, Hg was captured in the cyclone ash at temperatures below 300{sup o}C. During sludge monocombustion the retention of Hg in cyclone ash containing low loss on ignition (LOI) was not enough to decrease emissions below the EU regulated levels; hence, it is necessary to install dedicated flue gas treatment for Hg removal. The leachability and ecotoxicity of sludge and ash were also compared with the new regulatory limits for landfill disposal in the European Union (EU).

  19. Microscale combustion and power generation

    CERN Document Server

    Cadou, Christopher; Ju, Yiguang

    2014-01-01

    Recent advances in microfabrication technologies have enabled the development of entirely new classes of small-scale devices with applications in fields ranging from biomedicine, to wireless communication and computing, to reconnaissance, and to augmentation of human function. In many cases, however, what these devices can actually accomplish is limited by the low energy density of their energy storage and conversion systems. This breakthrough book brings together in one place the information necessary to develop the high energy density combustion-based power sources that will enable many of these devices to realize their full potential. Engineers and scientists working in energy-related fields will find: An overview of the fundamental physics and phenomena of microscale combustion; Presentations of the latest modeling and simulation techniques for gasphase and catalytic micro-reactors; The latest results from experiments in small-scale liquid film, microtube, and porous combustors, micro-thrusters, a...

  20. A review on paint sludge from automotive industries: Generation, characteristics and management.

    Science.gov (United States)

    Salihoglu, Guray; Salihoglu, Nezih Kamil

    2016-03-15

    The automotive manufacturing process results in the consumption of several natural sources and the generation of various types of wastes. The primary source of hazardous wastes at an automotive manufacturing plant is the painting process, and the major waste fraction is paint sludge, which is classified with EU waste code of 080113* implying hazardous characteristics. The amount of the paint sludge generated increases every year with the worldwide increase in the car production. The characteristics of the paint sludge, which mainly designate the management route, are mainly determined by the type of the paint used, application technique employed, and the chemicals applied such as flocculants, detackifiers, pH boosters, antifoam agents, and biocides as well as the dewatering techniques preferred. Major routes for the disposal of the paint sludges are incineration as hazardous waste or combustion at cement kilns. Because of high dissolved organic carbon content of the paint, the paint sludge cannot be accepted by landfills according to European Union Legislations. More investigations are needed in the field of paint sludge recycling such as recycling it as a new paint or as other formulations, or making use of the sludge for the production of construction materials. Research on the applicability of the paint sludge in composting and biogasification can also be useful. Ongoing research is currently being conducted on new application techniques to increase the effectiveness of paint transfer, which helps to prevent the generation of paint sludge. Advancements in paint and coating chemistry such as the reduction in the coating layers with its thickness also help to decrease the level of paint sludge generation. Investigations on the effects of the chemicals on the recycling potential of paint sludges and consideration of these effects by the chemical manufacturer companies would be extremely important. This review presents the formation of paint sludge, the factors

  1. Co-Combustion of Municipal Sewage Sludge and Hard Coal on Fluidized Bed Boiler WF-6

    Directory of Open Access Journals (Sweden)

    Rajczyk Rafał

    2014-12-01

    Full Text Available According to data of the Central Statistical Office, the amount of sludge produced in municipal wastewater treatment plants in 2010 amounted to 526000 Mg d.m. The forecast of municipal sewage sludge amount in 2015 according to KPGO2014 will reach 642400 Mg d.m. and is expected to increase in subsequent years. Significant amounts of sludge will create problems due to its utilization. In order to solve this problem the use of thermal methods for sludge utilization is expected. According to the National Waste Management Plan nearly 30% of sewage sludge mass should be thermally utilized by 2022. The article presents the results of co-combustion of coal and municipal sewage sludge in a bubbling fluidized bed boiler made by SEFAKO and located in the Municipal Heating Company in Morag. Four tests of hard coal and sewage sludge co-combustion have been conducted. Boiler performance, emissions and ash quality were investigated.

  2. Problematic issues of air protection during thermal processes related to the energetic uses of sewage sludge and other waste. Case study: Co-combustion in peaking power plant.

    Science.gov (United States)

    Hroncová, Emília; Ladomerský, Juraj; Musil, Juraj

    2018-03-01

    Currently, it is necessary to deal with issues related to the emissions as there is a constantly increasing interest in combusting sludge from sewage treatment plants in the boilers for wood. An analysis of the energetic importance of the combustion of sewage sludge has already been carried out, but the effects of various treatments of the sludge are not always clear, e.g. composting and subsequent combustion to the air pollution. Investments in other thermal processes of energetic utilisation of sewage sludge and organic waste are not always successfully implemented. The objective of this paper is to point out some problematic cases for acceptance of thermal processes related to energetic use of waste in terms of the air protection. The other aim is to mention the experience with solutions of such issues in Slovakia. There are mentioned first results of the operational validation experiments during the energy generation in circulating fluidized bed boiler in peaking power plant (Power 110MW) with the addition of the so-called alternative fuel based on wood and sewage sludge to the main fuel - black coal (anthracite). And there has already been achieved the highest share of 12.4%w. (dry matter) of sewage sludge in form of compost in blend with black coal, which is technologically viable. Moreover analyzed the problems of the authorization and operation of the co-combustion of sewage sludge and of combustion of products of various kinds of pyrolysis waste - pyrolysis gas and pyrolysis oil are analyzed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Gas Generation from K East Basin Sludges - Series II Testing

    International Nuclear Information System (INIS)

    Bryan, Samuel A.; Delegard, Calvin H.; Schmidt, Andrew J.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R.; Thornton, Brenda M.

    2004-01-01

    This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor, pit and canister sludge. Mixed and unmixed and fractionated KE canister sludge were tested, along with floor and pit sludges from areas in the KE Basin not previously sampled. The first report in this series focuses on gas generation from KE floor and canister sludge collected using a consolidated sampling technique. The third report presents results of gas generation testing of irradiated uranium fuel fragments with and without sludge addition. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. This report was originally published in March 2001. In January 2004, a transcription error was discovered in the value reported for the uranium metal content of KE North Loadout Pit sample FE-3. This revision of the report corrects the U metal content of FE-3 from 0.0013 wt% to 0.013 wt%

  4. Behaviour of Inorganic Constituents of Municipal Sewage Sludge during Fluidized-Bed Combustion.

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Pohořelý, Michael; Trnka, Otakar

    2007-01-01

    Roč. 61, 3 (2007) , s. 181-185 ISSN 0366-6352 R&D Projects: GA AV ČR(CZ) IAA4072201 Institutional research plan: CEZ:AV0Z40720504 Keywords : sewage sludge * heavy metals * fluidized-bed combustion Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.367, year: 2007

  5. The study of partitioning of heavy metals during fluidized bed combustion of sewage sludge and coal

    Energy Technology Data Exchange (ETDEWEB)

    Gulyurtlu, I.; Lopes, M.H.; Abelha, P.; Cabrita, I.; Oliveira, J.F.S. [INETI, Lisbon (Portugal)

    2006-06-15

    The behavior of Cd, Cr, Cu, Co, Mn, Ni, Pb, Zn, and Hg during the combustion tests of a dry granular sewage sludge on a fluidized bed combustor pilot (FBC) of about 0.3 MW was evaluated. The emissions of these heavy metals from mono-combustion were compared with those of co-combustion of the sludge with a bituminous coal. The effect of the addition of limestone was also studied in order to retain sulphur compounds and to verify its influence on the retention of heavy metals (HM). Heavy metals were collected and analyzed from different locations of the installation, which included the stack, the two cyclones, and the material removed from the bed. The results showed that the volatility of metals was rather low, resulting in emissions below the legal limits of the new directive on incineration, with the exception of Hg during the mono-combustion tests. The partitioning of metals, except for Hg, appeared to follow that of ashes, amounting to levels above 90% in the bed streams in the mono-combustion case. For co-combustion, there was a lower fixation of HM in the bed ashes, mostly originating essentially from the sewage sludge, ranging between 40% and 80%. It is believed that in this latter case, a slightly higher temperature could have enhanced the volatilization, especially of Cd and Pb. However these metals were then retained in fly ashes captured in the cyclones. In the case of Hg, the volatilisation was complete. The bed ashes were free of Hg and part of Hg was retained in the cyclones and the rest was emitted either with fine ash particles or in gaseous forms. In mono-combustion the Hg emissions from the stack (particles and gas) accounted, for about 50%. This appeared to have significantly decreased in the case of co-combustion, as only about 75% has been emitted, due to the retention effect of cyclone ashes.

  6. The study of partitioning of heavy metals during fluidized bed combustion of sewage sludge and coal

    Energy Technology Data Exchange (ETDEWEB)

    Gulyurtlu, Ibrahim; Lopes, M. Helena; Abelha, Pedro; Cabrita, Isabel; Oliveira, J.F. Santos

    2003-07-01

    The behaviour of Cd, Cr, Cu, Co, Mn, Pb, Zn and Hg during the combustion tests of granular dry sewage sludges on a pilot FBC of about 0,3 MW was evaluated. The emissions of these heavy metals from mono-combustion were compared with those of co-combustion of the sludge with a bituminous coal. The effect of the addition of limestone was also studied in order to retain sulphur compounds and to verify its influence on the retention of heavy metals. Heavy metals were collected and analysed from different locations of the installation, which included the stack, the two cyclones and the material removed from the bed. The results showed that the volatility of metals was rather low, resulting in emissions below the legal limits of the new directive on incineration, with the exception of Hg during the mono-combustion tests. The partitioning of metals, except for Hg, appeared to follow that of ashes, amounting to levels above 90% in the bed streams in the mono-combustion case. For co-combustion, there was a lower fixation of HM in the bed ashes, mostly originating essentially from the sewage sludge, ranging between 40 and 80%. It is believed that in this latter case, a slightly higher bed temperature could have enhanced the volatilisation, especially of Cd and Pb. However these metals were then retained in cyclone ashes. In the case of Hg, the volatilisation was complete. The bed ashes were free of Hg and part of it was retained in the cyclone and emitted as both fine ash particles and in gaseous forms. In mono-combustion the Hg emissions from the stack (particles and gas) accounted for about 50%, although there was a significant amount unaccounted for. This appeared to have significantly decreased in the case of co-combustion, as only about 15% has been emitted, due to the retention effect of cyclone ashes which presented high quantities of unburned carton and possibly condensed sulphur species.

  7. Gas Generation from K East Basin Sludges - Series I Testing

    International Nuclear Information System (INIS)

    Delegard, Calvin H.; Bryan, Samuel A.; Schmidt, Andrew J.; Bredt, Paul R.; King, Christopher M.; Sell, Rachel L.; Burger, Leland L.; Silvers, Kurt L.

    2000-01-01

    This report describes work to examine the gas generation behavior of actual K East (KE) Basin floor and canister sludge. The path forward for management of the K Basin Sludge is to retrieve, ship, and store the sludge at T Plant until final processing at some future date. Gas generation will impact the designs and costs of systems associated with retrieval, transportation and storage of sludge. The overall goals for this testing were to collect detailed gas generation rate and composition data to ascertain the quantity and reactivity of the metallic uranium (and other reactive species) present in the K Basin sludge. The gas generation evaluation included four large-scale vessels (850 ml) and eight small-scale vessels (30 ml) in an all-metal, leak tight system. The tests were conducted for several thousand hours at ambient and elevated temperatures (32 C, 40 C, 60 C, 80 C, and 95 C) to accelerated the reactions and provide conclusive gas generation data within a reasonable testing period. The sludge used for these tests was collected from the KE Basin floor and canister barrels (containing damaged spent fuel elements) using a consolidated sampling technique (i.e., material from several locations was combined to form ''consolidated samples''). Portions of these samples were sieved to separate particles greater than 250 m (P250) from particle less than 250 m (M250). This separation was performed to mimic the separation operations that are planned during the retrieval of certain K Basin sludge types and to gain a better understanding of how uranium metal is distributed in the sludge. The corrosion rate of the uranium metal particles in the sludge was found to agree reasonably well with corrosion rates reported in the literature

  8. Starved air combustion-solidification/stabilization of primary chemical sludge from a tannery.

    Science.gov (United States)

    Swarnalatha, S; Ramani, K; Karthi, A Geetha; Sekaran, G

    2006-09-01

    The high concentration of trivalent chromium along with organic/inorganic compounds in tannery sludge causes severe ground water contamination in the case of land disposal and chronic air pollution during incineration. In the present investigation, the sludge was subjected to flow-through column test to evaluate the concentration of leachable organics (tannin, COD and TOC) and heavy metal ions (Cr(3+), Fe(2+)) present in it. The dried sludge was incinerated at 800 degrees C in an incinerator under starved oxygen supply (starved-air combustion) to prevent the conversion of Cr(3+) to Cr(6+). The efficiency of starved air combustion was studied under different loading rates of sludge. The calcined sludge was solidified/stabilized using fly ash and Portland cement/gypsum. The solidified bricks were tested for unconfined compressive strength and heavy metal leaching. Unconfined compressive strength of the blocks was in the range of 83-156 kg/cm(2). The stabilization of chromium (III) in the cement gel matrix was confirmed with scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDX). Leachability studies on solidified bricks were carried out to determine the metal fixation and dissolved organic (as COD) concentration in the leachate.

  9. Analysis of briquetting process of sewage sludge with coal to combustion process

    Directory of Open Access Journals (Sweden)

    Kosturkiewicz Bogdan

    2016-01-01

    Full Text Available Energy recovery from sewage sludge can be achieved by several thermal technologies, but before those processes sewage sludge requires special pretreatment. The paper presents the investigation of the sewage sludge with coal briquettes as a fuel for combustion process. Research is conducted at Department of Manufacturing Systems and Department of Thermal Engineering and Environmental Protection, AGH University of Science and Technology to develop a technology of briquette preparation. The obtained results showed possibility of briquetting of municipal sewage sludge with coal in roll presses, equipped with asymmetric thickening gravity feed system. The following properties were determined for the obtained briquettes: density, drop strength and compressive strength. Based on physical and chemical analysis of prepared briquettes it was confirmed that briquettes have good fuel properties to combustion process. Thermal behaviour of studied sewage sludge and prepared mixture was investigated by thermogravimetric analysis (TG. For the thermo gravimetric analysis (TG the samples were heated in an alumina crucible from an ambient temperature up to 1000 °C at a constant rates: 10 °C/min, 40 °C/min and 100 °C/min in a 40 ml/min flow of air.

  10. Starved air combustion-solidification/stabilization of primary chemical sludge from a tannery

    Energy Technology Data Exchange (ETDEWEB)

    Swarnalatha, S. [Department of Environmental Technology, Central Leather Research Institute, Adyar, Chennai-600 020, Tamil Nadu (India); Ramani, K. [Department of Environmental Technology, Central Leather Research Institute, Adyar, Chennai-600 020, Tamil Nadu (India); Karthi, A. Geetha [Department of Environmental Technology, Central Leather Research Institute, Adyar, Chennai-600 020, Tamil Nadu (India); Sekaran, G. [Department of Environmental Technology, Central Leather Research Institute, Adyar, Chennai-600 020, Tamil Nadu (India)]. E-mail: ganesansekaran@hotmail.com

    2006-09-01

    The high concentration of trivalent chromium along with organic/inorganic compounds in tannery sludge causes severe ground water contamination in the case of land disposal and chronic air pollution during incineration. In the present investigation, the sludge was subjected to flow-through column test to evaluate the concentration of leachable organics (tannin, COD and TOC) and heavy metal ions (Cr{sup 3+}, Fe{sup 2+}) present in it. The dried sludge was incinerated at 800 deg. C in an incinerator under starved oxygen supply (starved-air combustion) to prevent the conversion of Cr{sup 3+} to Cr{sup 6+}. The efficiency of starved air combustion was studied under different loading rates of sludge. The calcined sludge was solidified/stabilized using fly ash and Portland cement/gypsum. The solidified bricks were tested for unconfined compressive strength and heavy metal leaching. Unconfined compressive strength of the blocks was in the range of 83-156 kg/cm{sup 2}. The stabilization of chromium (III) in the cement gel matrix was confirmed with scanning electron microscopy (SEM) and X-ray energy dispersive spectroscopy (EDX). Leachability studies on solidified bricks were carried out to determine the metal fixation and dissolved organic (as COD) concentration in the leachate.

  11. FINE PARTICAL AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt; Wayne S. Seames; Art Fernandez

    2003-09-21

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and pulverized coal. The objective was to determine potential tradeoffs between CO{sub 2} mitigation through using a CO{sub 2} neutral fuel, such as municipal sewage sludge, and the emergence of other potential problems such as the emission of toxic fly ash particles. The work led to new insight into mechanisms governing the partitioning of major and trace metals from the combustion of sewage sludge, and mixtures of coal and sewage sludge. The research also showed that the co-combustion of coal and sewage sludge emitted fine particulate matter that might potentially cause greater lung injury than that from the combustion of either coal alone or municipal sewage sludge alone. The reason appeared to be that the toxicity measured required the presence of large amounts of both zinc and sulfur in particles that were inhaled. MSS provided the zinc while coal provided the sulfur. Additional research showed that the toxic effects could most likely be engineered out of the process, through the introduction of kaolinite sorbent downstream of the combustion zone, or removing the sulfur from the fuel. These results are consequences of applying ''Health Effects Engineering'' to this issue. Health Effects Engineering is a new discipline arising out of this work, and is derived from using a collaboration of combustion engineers and toxicologists to mitigate the potentially bad health effects from combustion of this biomass fuel.

  12. Devolatilization and ash comminution of two different sewage sludges under fluidized bed combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Solimene, R.; Urciuolo, M.; Cammarota, A.; Chirone, R. [Istituto di Ricerche sulla Combustione (IRC) - CNR, Napoli (Italy); Salatino, P. [Istituto di Ricerche sulla Combustione (IRC) - CNR, Napoli (Italy); Dipartimento di Ingegneria Chimica Universita degli Studi di Napoli Federico II, Napoli (Italy); Damonte, G.; Donati, C.; Puglisi, G. [ECODECO Gruppo A2A, Giussago (PV) (Italy)

    2010-04-15

    Two different wet sewage sludges have been characterized under fluidized bed combustion conditions with reference to their devolatilization behavior and ash comminution with the aid of different and complementary experimental protocols. Analysis of the devolatilization process allowed to determine the size of fuel particle able to achieve effective lateral spreading of the volatile matter across the cross-section of medium-scale combustors. Primary fragmentation and primary ash particle characterization pointed out the formation of a significant amount of relatively large fragments. The mechanical properties of these fragments have been characterized by means of elutriation/abrasion tests using both quartz and sludge ash beds. (author)

  13. Evaluating the manufacturability and combustion behaviors of sludge-derived fuel briquettes.

    Science.gov (United States)

    Chiou, Ing-Jia; Wu, I-Tsung

    2014-10-01

    Based on the physical and chemical properties as well as calorific values of pulp sludge and textile sludge, this study investigates the differences between manufacturability, relationship between extrusion pressure and formability, as well as stability and combustion behaviors of extruded sludge-derived fuel briquettes (ESBB) and cemented sludge-derived fuel blocks (CSBB). The optimum proportion and relevant usage ESBB policies are proposed as well. Experimental results indicate that a large amount of water can be saved during the ESBB manufacturing process. Additionally, energy consumption decreases during the drying process. ESBB also has a more compact structure than that of CSBB, and its mean penetration loading is approximately 18.7 times higher as well. Moreover, the flame temperature of ESBB (624-968°C) is significantly higher than that of CSBB (393-517°C). Also, the dry bulk density and moisture regain of ESBB is significantly related to the penetration loading. Furthermore, the optimum mix proportion of ESBB is co-determined by the formability of pulp sludge and the calorific values of textile sludge. While considering the specific conditions (including formability, stability and calorific values), the recommended mix proportion for ESBB is PS50TS50. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Combustion behaviors and kinetics of sewage sludge blended with pulverized coal: With and without catalysts.

    Science.gov (United States)

    Wang, Zhiqiang; Hong, Chen; Xing, Yi; Li, Yifei; Feng, Lihui; Jia, Mengmeng

    2018-04-01

    The combustion behaviors of sewage sludge (SS), pulverized coal (PC), and their blends were studied using a thermogravimetric analyzer. The effect of the mass ratio of SS to PC on the co-combustion characteristics was analyzed. The experiments showed that the ignition performance of the blends improved significantly as the mass percentage of SS increased, but its combustion intensity decreased. The burnout temperature (T b ) and comprehensive combustibility index (S) of the blends were almost unchanged when the mass percentage of SS was less than 10%. However, a high mass percentage of SS (>10%) resulted in a great increase in T b and a notable decrease in S. Subsequently, the effects of different catalysts (CaO, CeO 2 , MnO 2 , and Fe 2 O 3 ) on the combustion characteristics and activation energy of the SS/PC blend were investigated. The four catalysts promoted the release and combustion of volatile matters in the blended fuels and shifted their combustion profiles to a low temperature. In addition, their peak separating tendencies were obvious at 350-550 C, resulting in high peak widths. All the catalysts improved combustion activity of the blended fuel and accelerated fixed carbon combustion, which decreased the ignition temperature and burnout temperature of the fuels. CeO 2 had the best catalytic effects in terms of the comprehensive combustion performance and activation energy, followed closely by Fe 2 O 3 . However, the rare-earth compounds are expensive to be applied in the catalytic combustion process of SS/PC blend at present. Based on both catalytic effects and economy, Fe 2 O 3 was potentially an optimal option for catalytic combustion among the tested catalysts. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Combustion of Dried Sewage Sludge in a Fluidized-Bed Reactor

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Trnka, Otakar

    2005-01-01

    Roč. 44, č. 10 (2005), s. 3432-3441 ISSN 0888-5885 R&D Projects: GA AV ČR(CZ) IAA4072201 Institutional research plan: CEZ:AV0Z40720504 Keywords : fluidized-bed combustion * dried sewage sludge * CO, NOx, and N2O emissions Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.504, year: 2005

  16. The use of sewage sludge as additive to avoid operational problems at combustion of shredder residues

    International Nuclear Information System (INIS)

    Gyllenhammar, Marianne

    2010-01-01

    When shredder light fraction (SLF) from recovery of metal scrap is energy recovered it is usually mixed with more than 90% of other wastes. SLF is a fuel with high energy content but also with relatively high chlorine and metal content and could cause deposit and corrosion problems in incineration plants. Sewage sludge has previously been shown to reduce deposition and corrosion problems in combustion of alkali and chlorine containing biomass. In this work 20 % SLF (by energy content) has been combusted together with municipal solid waste and industrial wastes, with and without addition of 3 % (by energy content) sewage sludge. The initial fireside corrosion rate was then compared to the corrosion rate during combustion of the normal fuel mix, i.e. only municipal solid waste and industrial wastes. The tests were done at the 20 MW fluidized bed boiler of Lidkoping heat production plant. During the tests air-cooled corrosion and deposit probes were exposed for 24 hours. Deposit probes were placed at three different flue gas temperatures - in the combustion chamber, upstream and downstream the convection pass. The corrosion probes were placed upstream the convection pass and on the probes there were three different materials at three different water temperatures (280, 350 and 420 degree Celsius). The tests showed that sewage sludge could help avoiding deposition and corrosion problems when incinerating SLF. The amount of deposits was reduced and the content of the deposits was less corrosive when sewage sludge was added. The project was financed by Waste Refinery as a collaboration project between Stena Metall AB, Metso AB, High Temperature Corrosion Center at Chalmers University of Technology, SP Technical Research Institute of Sweden and Lidkopings Varmeverk. (author)

  17. Design of jet manipulator for sludge lancing for steam generators

    International Nuclear Information System (INIS)

    Kumar, Kundan; Nathani, D.K.; Kayal, J.N.; Rupani, B.B.

    2006-01-01

    The sludge accumulation in secondary side of mushroom type steam generators of Indian Pressurised Heavy Water Reactors (PHWRs) may lead to loss of thermal efficiency and corrosion. Sludge removal is required to minimise such effects for safe and enhanced operating life of the steam generators. A sludge lancing system has been developed for sludge removal from the secondary side of the steam generators. Jet Manipulator is one of the various modules of the sludge lancing system. The JM consists of three modules namely walker, elevator and nozzle heads. Each module is designed to pass through hand hole, having 180 mm diameter and 100 mm wide gap between steam generator shell and shroud. These three modules are connected to each other by quick connecting type joints and are having their specific functions. The walker crawls by step of single pitch of the tube along the central no-tube lane of the steam generator by taking lateral supports on the nearest tubes. The elevator is capable of lifting the nozzle head to a suitable height required for lancing operation of entire tube sheet of the steam generator. The nozzle head directs the multiple jets along the narrow inter tube lanes having 3 mm width, on both sides of the central no-tube lane. The nozzle can be set to move at different elevations such that the multiple jets will graze along the narrow tube lane to create the sludge lancing action. The provision exists for movement of JM in both directions, i.e. forward and reverse. This paper highlights the objective, design and development, selection of nozzles, qualification and performance evaluation of JM. The manipulator is remotely operable by compressed air in the forward and reverse direction in the central no-tube lane to position the nozzle head in the horizontal direction. (author)

  18. Combustion generated noise in gas turbine combustors

    Science.gov (United States)

    Strahle, W. C.; Shivashankara, B. N.

    1975-01-01

    Experiments are conducted for the noise power and spectra emitted from a gas turbine combustor can exhausting to the atmosphere. The theory of combustion noise is applied to the results to determine the noise generating capability of the flame in the absence of reflecting can surfaces. The results show that for a fixed fuel (JP-4) the noise output is independent of fuel/air ratio for well stabilized can-type flames and heavily dependent on airflow while the spectra are dominated by the can acoustics, primarily through sound absorption by the liner. In an installed configuration the noise output depends heavily on the enclosure acoustics. Scaling rules are presented for installed configurations.

  19. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt

    2001-05-04

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and coal. The objective is to determine the relationship between (1) fraction sludge in the sludge/coal mixture, and (2) combustion conditions on (a) NO{sub x} concentrations in the exhaust, (b) the size segregated fine and ultra-fine particle composition in the exhaust, and (c) the partitioning of toxic metals between vapor and condenses phases, within the process. To this end we shall use an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. The proposed study will be conducted in concert with an existing ongoing research on toxic metal partitioning mechanisms for very well characterized pulverized coals alone. Both high NO{sub x} and low NO{sub x} combustion conditions will be investigated (unstaged and staged combustion). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined.

  20. Study on Influence to Waste Water Treatment Plant’s Sludge by Low-carbon Catalytic Combustion Furnace of Natural Gas

    OpenAIRE

    Ren TianQi; Fang Kai; Zhang Shihong

    2016-01-01

    There are two parts in this experiment. One of is about the concentration of Variation of exhaust gas while heating sludge of waste water treatment plant. The other one is about introduce the problems of the traditional incineration processes of sludge of waste water treatment as compared between the sludge heated by natural gas catalytic combustion furnace and the tradition’s. We can see that natural gas low-carbon catalytic combustion furnace realize the near-zero emission of contaminates.

  1. Chemical speciation, mobility and phyto-accessibility of heavy metals in fly ash and slag from combustion of pelletized municipal sewage sludge.

    Science.gov (United States)

    Xiao, Zhihua; Yuan, Xingzhong; Li, Hui; Jiang, Longbo; Leng, Lijian; Chen, Xiaohong; Zeng, Guangming; Li, Fei; Cao, Liang

    2015-12-01

    Combustion of pelletized municipal sewage sludge (MSS) can generate pestilent byproducts: fly ash and slag. Comparisons of heavy metal sequential extraction results among MSS, fly ash and slag showed that after combustion, the bioavailable heavy metal fractions (acid soluble/exchangeable, reducible and oxidizable fractions) were mostly transformed into the very stable heavy metal fractions (residual fractions). On the other hand, the results of toxicity characteristic leaching procedure (TCLP), diethylenetriamine pentaacetic acid and HCl extraction (phyto-accessibility assessment) demonstrated that the mobility and toxicity of heavy metals were greatly reduced. The direct and long-term bioavailability and eco-toxicity of heavy metals in fly ash and slag were relieved, which implied that combustion of pelletized MSS could be a promising and completely safe disposal technology for MSS treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Biomass combustion technologies for power generation

    Energy Technology Data Exchange (ETDEWEB)

    Wiltsee, G.A. Jr. [Appel Consultants, Inc., Stevenson Ranch, CA (United States); McGowin, C.R.; Hughes, E.E. [Electric Power Research Institute, Palo Alto, CA (United States)

    1993-12-31

    Technology in power production from biomass has been advancing rapidly. Industry has responded to government incentives such as the PURPA legislation in the US and has recognized that there are environmental advantages to using waste biomass as fuel. During the 1980s many new biomass power plants were built. The relatively mature stoker boiler technology was improved by the introduction of water-cooled grates, staged combustion air, larger boiler sizes up to 60 MW, higher steam conditions, and advanced sootblowing systems. Circulating fluidized-bed (CFB) technology achieved full commercial status, and now is the leading process for most utility-scale power applications, with more complete combustion, lower emissions, and better fuel flexibility than stoker technology. Bubbling fluidized-bed (BFB) technology has an important market niche as the best process for difficult fuels such as agricultural wastes, typically in smaller plants. Other biomass power generation technologies are being developed for possible commercial introduction in the 1990s. Key components of Whole Tree Energy{trademark} technology have been tested, conceptual design studies have been completed with favorable results, and plans are being made for the first integrated process demonstration. Fluidized-bed gasification processes have advanced from pilot to demonstration status, and the world`s first integrated wood gasification/combined cycle utility power plant is starting operation in Sweden in early 1993. Several European vendors offer biomass gasification processes commercially. US electric utilities are evaluating the cofiring of biomass with fossil fuels in both existing and new plants. Retrofitting existing coal-fired plants gives better overall cost and performance results than any biomass technologies;but retrofit cofiring is {open_quotes}fuel-switching{close_quotes} that provides no new capacity and is attractive only with economic incentives.

  3. Risk assessment of heavy metals from combustion of pelletized municipal sewage sludge.

    Science.gov (United States)

    Xiao, Zhihua; Yuan, Xingzhong; Leng, Lijian; Jiang, Longbo; Chen, Xiaohong; Zhibin, Wu; Xin, Peng; Jiachao, Zhang; Zeng, Guangming

    2016-02-01

    Fly ash and slag are important by-products obtained from combustion of municipal sewage sludge (MSS) after pelletization. The quantitative environmental impact assessment of heavy metals in fly ash and slag, compared to MSS, were performed in accordance with bioavailability and eco-toxicity, geo-accumulation index (GAI), risk assessment code (RAC), and potential ecological risk index (PERI). The results demonstrated that not only direct but also long-term bioavailability and eco-toxicity of heavy metals in fly ash and slag decreased except direct bioavailability and eco-toxicity of Pb in fly ash. The GAI demonstrated that combustion significantly weakened (P < 0.05) the pollution levels of heavy metals. PERI indicated that all risks attributed to heavy metals were significantly lowered (P < 0.05) from 777.07 (very high risk) in MSS to 288.72 (moderate risk) and 64.55 (low risk) in fly ash and slag, respectively. In terms of the RAC, seven heavy metals had low even no risk to the environments after combustion besides As in slag. The environmental risk of heavy metals in fly ash and slag was decreased compared with MSS. However, the results of PERI showed that fly ash had a moderate risk.

  4. Effect of hydrothermal carbonization temperature on combustion behavior of hydrochar fuel from paper sludge

    International Nuclear Information System (INIS)

    Lin, Yousheng; Ma, Xiaoqian; Peng, Xiaowei; Hu, Shanchao; Yu, Zhaosheng; Fang, Shiwen

    2015-01-01

    Different temperatures in the range of 180–300 °C were applied to evaluate the effect of hydrothermal carbonization (HTC) temperature on hydrochar fuel characteristics and thermal behavior. The hydrochar produced at 210 °C had the maximum heating value (9763 kJ/kg) with the highest energetic recovery efficiency (90.12%). Therefore, 210 °C could be the optimum temperature for HTC of paper sludge. With raising the temperature, noticeable decreases in nitrogen and sulfur contents with lower oxygen/carbon and hydrogen/carbon atomic ratios were observed. In addition, the slagging and fouling problems were dramatically mitigated due to efficiently remove of major ash forming contents, especially for chlorine, sodium and potassium. Finally, thermal gravimetric analysis showed that HTC temperature had a significant impact on combustion behavior and activation energy of hydrochars. The first combustion decomposition peak of hydrochars treated at 180, 210 and 240 °C, were much higher that other samples, leading to a better combustion performance. - Highlights: • Higher heating value was increased by all hydrochars tests by up to 8%. • Hydrochars showed lower N, S contents and higher fuel ratio. • High removal rates of Cl, Na and K contents were achieved during HTC process. • The optimal temperature of HTC was approximately 210 °C to make clean solid fuel.

  5. Investigation of Excess Sludge Generated from Activated Sludge Treatment Plant of Concentrated Latex Factories: An Investigative Case Study in Southern Thailand

    Directory of Open Access Journals (Sweden)

    Wanrudee Wanseng

    2017-06-01

    Full Text Available Activated sludge technology has been employed for wastewater treatment in the concentrated latex factories in the south of Thailand. This paper highlights the survey results of the excess sludge generated from activated sludge treatment plants of the concentrated latex factories, including sludge generation rate, sludge characteristics, as well as sludge management and its problems. The total number of 11 factories was investigated. The findings showed that 20% of the investigated factories using activated sludge did not know how much the excess sludge generation rate was. With an in-depth investigation, the excess sludge generation rate was determined as for 28 kg/ton concentrated latex product or 10 kg/ton of field latex used in the concentrated latex factories. The excess sludge had a low C/N ratio with an average value of 4.7 and contained N, P, and K with the average of percentage values of 8.0, 2.0, and 1.0% dry basis, respectively. However, the excess sludge consisted of Zn with an average of 3.01% dry basis. 60% of the investigated factories using an activated sludge system had issues concerning the management of excess sludge. Moreover, various aspects of the excess sludge management were discussed and lessons were learned on the current excess sludge management of the concentrated latex industry in the south of Thailand.

  6. Fertilisers production from ashes after sewage sludge combustion - A strategy towards sustainable development.

    Science.gov (United States)

    Gorazda, Katarzyna; Tarko, Barbara; Wzorek, Zbigniew; Kominko, Halyna; Nowak, Anna K; Kulczycka, Joanna; Henclik, Anna; Smol, Marzena

    2017-04-01

    Sustainable development and circular economy rules force the global fertilizer industry to develop new phosphorous recovery methods from alternative sources. In this paper a phosphorus recovery technology from Polish industrial Sewage Sludge Ashes was investigated (PolFerAsh - Polish Fertilizers form Ash). A wet method with the use of mineral acid and neutralization was proposed. Detailed characteristic of SSA from largest mono-combustion plans were given and compared to raw materials used on the market. The technological factors associated with such materials were discussed. The composition of the extracts was compared to typical industrial phosphoric acid and standard values characterizing suspension fertilizers. The most favorable conditions for selective precipitation of phosphorus compounds were revealed. The fertilizers obtained also meet EU regulations in the case of the newly discussed Cd content. The process was scaled up and a flow mass diagram was defined. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt

    2002-02-05

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and coal. The objective is to determine the relationship between (1) fraction sludge in the sludge/coal mixture, and (2) combustion conditions on (a) NO{sub x} concentrations in the exhaust, (b) the size segregated fine and ultra-fine particle composition in the exhaust, and (c) the partitioning of toxic metals between vapor and condenses phases, within the process. To this end work is progress using an existing 17kW downflow laboratory combustor, available with coal and sludge feed capabilities. The proposed study will be conducted in concert with an existing ongoing research on toxic metal partitioning mechanisms for very well characterized pulverized coals alone. Both high NO{sub x} and low NO{sub x} combustion conditions will be investigated (unstaged and staged combustion). The proposed work uses existing analytical and experimental facilities and draws on 20 years of research on NO{sub x} and fine particles that has been funded by DOE in this laboratory. Four barrels of dried sewage sludge are currently in the laboratory. Insofar as possible pertinent mechanisms will be elucidated. Tradeoffs between CO{sub 2} control, NO{sub x} control, and inorganic fine particle and toxic metal emissions will be determined. Progress in the Sixth Quarter (January 1, 2002 through March 31, 2002) was slow because of slagging problems in the combustor. These required the combustor to be rebuilt, a job that is not yet complete. A paper describing our results heretofore has been accepted by the Journal Environmental Science and Technology.

  8. NOx, FINE PARTICLE AND TOXIC METAL EMISSIONS FROM THE COMBUSTION OF SEWAGE SLUDGE/COAL MIXTURES: A SYSTEMATIC ASSESSMENT

    Energy Technology Data Exchange (ETDEWEB)

    Jost O.L. Wendt

    2002-08-15

    This research project focuses on pollutants from the combustion of mixtures of dried municipal sewage sludge (MSS) and coal. The objective is to determine the relationship between (1) fraction sludge in the sludge/coal mixture, and (2) combustion conditions on (a) NOx concentrations in the exhaust, (b) the size segregated fine and ultra-fine particle composition in the exhaust, and (c) the partitioning of toxic metals between vapor and condenses phases, within the process. The proposed study will be conducted in concert with an existing ongoing research on toxic metal partitioning mechanisms for very well characterized pulverized coals alone. Both high NOx and low NOx combustion conditions will be investigated (unstaged and staged combustion). Tradeoffs between CO2 control, NOx control, and inorganic fine particle and toxic metal emissions will be determined. Previous research has yielded data on trace metal partitioning for MSS by itself, with natural gas assist, for coal plus MSS combustion together, and for coal alone. We have re-evaluated the inhalation health effects of ash aerosol from combustion of MSS both by itself and also together with coal. We have concluded that ash from the co-combustion of MSS and coal is very much worse from an inhalation health point of view, than ash from either MSS by itself or coal by itself. The reason is that ZnO is not the ''bad actor'' as had been suspected before, but the culprit is, rather, sulfated Zn. The MSS supplies the Zn and the coal supplies the sulfur, and so it is the combination of coal and MSS that makes that process environmentally bad. If MSS is to be burned, it should be burned without coal, in the absence of sulfur.

  9. Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor

    International Nuclear Information System (INIS)

    Lapa, N.; Barbosa, R.; Lopes, M.H.; Mendes, B.; Abelha, P.; Gulyurtlu, I.; Santos Oliveira, J.

    2007-01-01

    In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran[reg]), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran[reg]) are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub

  10. Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor.

    Science.gov (United States)

    Lapa, N; Barbosa, R; Lopes, M H; Mendes, B; Abelha, P; Boavida, D; Gulyurtlu, I; Oliveira, J Santos

    2007-08-17

    In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub-products of such type

  11. Chemical and ecotoxicological characterization of ashes obtained from sewage sludge combustion in a fluidised-bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lapa, N. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal)]. E-mail: ncsn@fct.unl.pt; Barbosa, R. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal); Lopes, M.H. [National Institute of Engineering, Technology and Innovation (INETI), Department of Energetic Engineering and Environmental Control (DEECA). Edificio J, Estrada do Paco do Lumiar, 22, 1649-038 Lisbon (Portugal); Mendes, B. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal); Abelha, P. [National Institute of Engineering, Technology and Innovation (INETI), Department of Energetic Engineering and Environmental Control (DEECA). Edificio J, Estrada do Paco do Lumiar, 22, 1649-038 Lisbon (Portugal); Gulyurtlu, I. [National Institute of Engineering, Technology and Innovation (INETI), Department of Energetic Engineering and Environmental Control (DEECA). Edificio J, Estrada do Paco do Lumiar, 22, 1649-038 Lisbon (Portugal); Santos Oliveira, J. [Environmental Biotechnology Researching Unit (UBiA), Faculty of Science and Technology (FCT), New University of Lisbon - UNL, Ed. Departamental, piso 3, gabinete 377, Quinta da Torre, 2829-516 Caparica (Portugal)

    2007-08-17

    In 1999, the DEECA/INETI and the UBiA/FCT/UNL started a researching project on the partition of heavy metals during the combustion of stabilised sewage sludge (Biogran[reg]), in a fluidised-bed reactor, and on the quality of the bottom ashes and fly ashes produced. This project was entitled Bimetal and was funded by the Portuguese Foundation for Science and Technology. In this paper only the results on the combustion of Biogran[reg]) are reported. The combustion process was performed in two different trials, in which different amounts of sewage sludge and time of combustion were applied. Several ash samples were collected from the bed (bottom ashes) and from two cyclones (first cyclone and second cyclone ashes). Sewage sludge, bed material (sand) and ash samples were submitted to the leaching process defined in the European leaching standard EN 12457-2. The eluates were characterized for a set of inorganic chemical species. The ecotoxicological levels of the eluates were determined for two biological indicators (Vibrio fischeri and Daphnia magna). The results were compared with the limit values of the CEMWE French Regulation. The samples were also ranked according to an index based on the chemical characterization of the eluates. It was observed an increase of the concentration of metals along the combustion system. The ashes trapped in the second cyclone, for both combustion trials, showed the highest concentration of metals in the eluates. Chemically, the ashes of the second cyclone were the most different ones. In the ecotoxicological point of view, the ecotoxicity levels of the eluates of the ashes, for both combustion cycles, did not follow the same pattern as observed for the chemical characterization. The ashes of the first cyclone showed the highest ecotoxicity levels for V. fischeri and D. magna. This difference on chemical and ecotoxicological results proves the need for performing both chemical and ecotoxicological characterizations of the sub

  12. Combustion of paper industry sewage sludge in existing boilers. Progress report 1; Tillfoersel av skogsindustriellt slam till eldstaeder. Delrapport etapp 1

    Energy Technology Data Exchange (ETDEWEB)

    Hoeglund, Christer; Lundborg, Rickard; Myringer, Aase

    2003-10-01

    The aim of this project is to find a feasible method for combustion of sewage sludge in existing boilers of the paper industry. Biological sludge is complicated to handle since it contains a lot of bound water. Problems arise at dehydration and subsequent treatment. Moreover, the trend is that the amount of biological sludge increases whereas the amount of easily dehydrated fibre sludge decreases. Today, mixed sludge is combusted at more then half of the paper and pulp mills in Sweden. In order to evaluate the existing problems and the characteristics of different sludge, five mills have been studied. Sludge from three of these mills has also been analysed with regards to content and combustion properties. The content of sludge from different mills varies greatly. If the ash content is high, some substances, especially the alkali metals can cause problems at combustion such as sintering and deposits in the boiler. The analysed sludge did not contain important amounts of substances that causes problems at combustion, nor any toxic substances, except from one mill that had relatively high content of mercury. The combustion tests proved that combustion and especially drying of sludge is made preferably when the sludge particles are small, on as big an area as possible. One feasible method to combust sludge from the forest industry is to dehydrate so called fibre sludge to the same dry substance content as bark, in order to introduce it with existing fuel feeding devises and combust it together with the other fuel on the grate in a grate boiler. Dehydrated biological sludge, with considerably higher moisture content than pure fibre sludge, is added with a burner devise above the bed. The sludge particles are dried (in the furnace) and combusted before they leave the furnace. In this way, wet sludge that plug the bed is avoided. The location of the sludge feeding device in the boiler is important and should be adjusted individually to each furnace. Simulations show that

  13. The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, M.H.; Abelha, P.; Lapa, N.; Oliveira, J.S.; Cabrita, I.; Gulyurtlu, I. [INETI, Lisbon (Portugal)

    2003-07-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC with the aim of characterizating the ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials.

  14. Study on Influence to Waste Water Treatment Plant’s Sludge by Low-carbon Catalytic Combustion Furnace of Natural Gas

    Directory of Open Access Journals (Sweden)

    Ren TianQi

    2016-01-01

    Full Text Available There are two parts in this experiment. One of is about the concentration of Variation of exhaust gas while heating sludge of waste water treatment plant. The other one is about introduce the problems of the traditional incineration processes of sludge of waste water treatment as compared between the sludge heated by natural gas catalytic combustion furnace and the tradition’s. We can see that natural gas low-carbon catalytic combustion furnace realize the near-zero emission of contaminates.

  15. Combustion of sewage sludge water in Netherland; Incineracion de lodos procedentes de aguas residuales en Holanda

    Energy Technology Data Exchange (ETDEWEB)

    Viles, A. W. van der

    1995-12-31

    The Dutch policy for sewage sludge disposal has been changed in the last decades. Instead of predominantly beneficial use thermal processes, such as sludge drying and incineration, will become increasely more necessary. These processes are subject to very strict environmental regulations. Sludge incineration has to meet the very strict flue gas emission requirements of the Dutch Guideline on Incineration. The consequences for a new sludge incineration plant are reviewed.

  16. Investigation on the fast co-pyrolysis of sewage sludge with biomass and the combustion reactivity of residual char.

    Science.gov (United States)

    Deng, Shuanghui; Tan, Houzhang; Wang, Xuebin; Yang, Fuxin; Cao, Ruijie; Wang, Zhao; Ruan, Renhui

    2017-09-01

    Gaining the valuable fuels from sewage sludge is a promising method. In this work, the fast pyrolysis characteristics of sewage sludge (SS), wheat straw (WS) and their mixtures in different proportions were carried out in a drop-tube reactor. The combustion reactivity of the residual char obtained was investigated in a thermogravimetric analyzer (TGA). Results indicate that SS and WS at different pyrolysis temperatures yielded different characteristic gas compositions and product distributions. The co-pyrolysis of SS with WS showed that there existed a synergistic effect in terms of higher gas and bio-oil yields and lower char yield, especially at the WS adding percentage of 80wt%. The addition of WS to SS increased the carbon content in the SS char and improved char porous structures, resulting in an improvement in the combustion reactivity of the SS char. The research results can be used to promote co-utilization of sewage sludge and biomass. Copyright © 2017. Published by Elsevier Ltd.

  17. Rotating Detonation Combustion: A Computational Study for Stationary Power Generation

    Science.gov (United States)

    Escobar, Sergio

    The increased availability of gaseous fossil fuels in The US has led to the substantial growth of stationary Gas Turbine (GT) usage for electrical power generation. In fact, from 2013 to 2104, out of the 11 Tera Watts-hour per day produced from fossil fuels, approximately 27% was generated through the combustion of natural gas in stationary GT. The thermodynamic efficiency for simple-cycle GT has increased from 20% to 40% during the last six decades, mainly due to research and development in the fields of combustion science, material science and machine design. However, additional improvements have become more costly and more difficult to obtain as technology is further refined. An alternative to improve GT thermal efficiency is the implementation of a combustion regime leading to pressure-gain; rather than pressure loss across the combustor. One concept being considered for such purpose is Rotating Detonation Combustion (RDC). RDC refers to a combustion regime in which a detonation wave propagates continuously in the azimuthal direction of a cylindrical annular chamber. In RDC, the fuel and oxidizer, injected from separated streams, are mixed near the injection plane and are then consumed by the detonation front traveling inside the annular gap of the combustion chamber. The detonation products then expand in the azimuthal and axial direction away from the detonation front and exit through the combustion chamber outlet. In the present study Computational Fluid Dynamics (CFD) is used to predict the performance of Rotating Detonation Combustion (RDC) at operating conditions relevant to GT applications. As part of this study, a modeling strategy for RDC simulations was developed. The validation of the model was performed using benchmark cases with different levels of complexity. First, 2D simulations of non-reactive shock tube and detonation tubes were performed. The numerical predictions that were obtained using different modeling parameters were compared with

  18. Sludge cleaning in the steam generators: sludge Lancing e IBL; Limpieza de lodos en los generadores de vapor: Sludge Lancing IBL

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, E.; Gonzalez, S.; Calderon, N.

    2013-09-01

    IBERDROLA Engineering and Construction has echoed the need for plants to remove oxide deposits (sludge) located on the secondary side, on the bottom plate and into the tube bundle steam steam generators. Therefore, and with its partner SAVAC SRA has developed a specific system consisting of applying a capillary water at very high pressure applied directly to the location of these oxides. (Author)

  19. Steam generation by combustion of processed waste fats

    Energy Technology Data Exchange (ETDEWEB)

    Pudel, F.; Lengenfeld, P. [OEHMI Forschung und Ingenieurtechnik GmbH, Magdeburg (Germany)

    1993-12-31

    The use of specially processed waste fats as a fuel oil substitute offers, at attractive costs, an environmentally friendly alternative to conventional disposal like refuse incineration or deposition. For that purpose the processed fat is mixed with EL fuel oil and burned in a standard steam generation plant equipped with special accessories. The measured emission values of the combustion processes are very low.

  20. Characteristics of ammonia emission during thermal drying of lime sludge for co-combustion in cement kilns.

    Science.gov (United States)

    Liu, Wei; Xu, Jingcheng; Liu, Jia; Cao, Haihua; Huang, Xiang-Feng; Li, Guangming

    2015-01-01

    Thermal drying was used to reduce sludge moisture content before co-combustion in cement kilns. The characteristics of ammonia (NH3) emission during thermal drying of lime sludge (LS) were investigated in a laboratory-scale tubular dry furnace under different temperature and time conditions. As the temperature increased, the NH3 concentration increased in the temperature range 100-130°C, decreased in the temperature range 130-220°C and increased rapidly at >220°C. Emission of NH3 also increased as the lime dosage increased and stabilized at lime dosages>5%. In the first 60 min of drying experiments, 55% of the NH3 was released. NH3 accounted for about 67-72% of the change in total nitrogen caused by the release of nitrogen-containing volatile compounds (VCs) from the sludge. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy revealed that the main forms of nitrogen in sludge were amides and amines. The addition of lime (CaO) could cause conversion of N-H, N-O or C-N containing compounds to NH3 during the drying process.

  1. Characteristics of oil sludge from crude oil terminal and behaviors of the naturally occurring radioactive materials and heavy metals on combustion of the sludge

    International Nuclear Information System (INIS)

    Mohamad Puad Abu

    2001-01-01

    The study on the characteristics and behaviors of Naturally Occurring Radioactive Materials (NORM) and heavy metals (HM) in the oil sludge from the crude oil terminal were performed using Gamma Spectroscopy (GM), Neutron Activation Analysis Instrumental (NAAI) and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS). GM and NAAI were used to analyze the concentrations of radionuclides whereas NAAI as well as ICP-MS techniques were applied for HM. The samples were then combusted at temperature ranging from 100 degree Celsius - 800 degree Celsius for a period of 30-150 minutes. The ashes produced were then analyzed again for the various elemental concentrations by the above techniques. The percentage of volatilization was then derived mathematically. The concentration of Ra-226 (123 Bq/ kg) and Ra-228 (117 Bq/ kg) in the oil sludge are higher compared with their parent U-238 (32.12 Bq/ kg) and Th-232 (35.36 Bq/ kg). The concentration of HM such as As (13.30 ppm), Cr (46 ppm) and Zn (4287 ppm) in the oil sludge are also higher compared with As (7.5 ppm), Cr (43 ppm) and Zn (36 ppm) contain in the Malaysian normal soil. The heating value for crude oil sludge is 9000 kJ/ kg which is below the value for self-sustaining combustion (11000 kJ/ kg). The percentage of volatilization varies from 2-70 % depends on the elements, temperature and period of combustion. Uranium was found to volatile more than other elements. Higher temperatures (>500 degree Celsius) and longer exposure time (>90 minutes) promoted metal and radionuclide volatilization significantly more than 20 %. Based on the first order kinetic reaction, a new global mathematical model was developed (Q e =1-e -k e t ). This model can predict the percentage of volatilization for the various elements contain in the sludge if the temperature and time of combustion are known. With this known percentage of volatilization, the concentration of various elements present in the bottom and fly ashes can be deduced. From

  2. Generation of indirect combustion noise by compositional inhomogeneities

    Science.gov (United States)

    Magri, Luca; O'Brien, Jeff; Ihme, Matthias

    2016-11-01

    The generation of indirect combustion noise in nozzles and turbine stages is commonly attributed to temperature inhomogeneities and vorticity fluctuations. Here, compositional inhomogeneities in a multi-component gas mixture are shown to produce indirect noise both theoretically and numerically. The chemical potential function is introduced as an additional acoustic source mechanism. The contribution of the compositional noise is compared to the entropy noise and direct noise by considering subsonic, supersonic and shocked nozzles downstream of the combustor exit. It is shown that the compositional noise is dependent on the local mixture composition and can exceed entropy noise for fuel-lean conditions and supersonic/shocked nozzle flows. This suggests that compositional indirect combustion noise may require consideration with the implementation of advanced combustion concepts in gas turbines, including low-emissions combustors, high-power-density engine cores, or compact burners.

  3. The behavior of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Helena M.; Abelha, P.; Cabrita, I. [INETI-DEECA, Lisboa (Portugal); Lapa, N.; Oliveira, J.S. [UNL-Ubia, Monte de Caparica (Portugal)

    2003-07-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FRC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their reactor further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out, and the amount of unburned carbon leaving the combustor but captured in the cyclone was large enough to ensure substantial retention of mercury at low temperatures, and, hence, could contribute to an improvement of the mercury release, which still remains an issue of great concern to resolve during combustion of waste materials.

  4. The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed.

    Science.gov (United States)

    Helena Lopes, M; Abelha, P; Lapa, N; Oliveira, J S; Cabrita, I; Gulyurtlu, I

    2003-01-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials.

  5. The behaviour of ashes and heavy metals during the co-combustion of sewage sludges in a fluidised bed

    International Nuclear Information System (INIS)

    Helena Lopes, M.; Abelha, P.; Lapa, N.; Oliveira, J.S.; Cabrita, I.; Gulyurtlu, I.

    2003-01-01

    Co-combustion tests of dry sewage sludges with coal were performed in a pilot bubbling FBC aiming at the characterization of ashes and determining the behaviour of heavy metals in the process. The tests showed compliance with the regulatory levels as far as heavy metal emissions were concerned. The bottom ashes, which accounted for about 70% of the total ash production, were obtained in a granular form, with diameters ranging from 0.5 to 4 mm. The heavy metals were distributed in ashes obtained from different locations of the installation and their concentrations were found to vary depending on the location of capture. The increase in heavy metals content in bottom ashes was not found to lead to higher leachability and ecotoxicity compared to sewage sludges, suggesting that there could be opportunities for their further use. Mercury suffered vaporisation inside the reactor, thus leaving bottom ashes free of contamination by it. However, there was observed a strong retention of mercury in cyclone ashes due to the presence of unburned carbon which probably acted as an adsorbent. The effluent mercury was also found to be mostly associated with the particulate fraction, being less than 20% emitted in gaseous forms. The results suggested that the combustion of the sewage sludge could successfully be carried out and the amount of unburned carbon leaving the combustor but captured in cyclone was large enough to ensure substantial retention of mercury at low temperatures, hence could contribute to an improvement of the mercury release which still remains an issue of great concern to resolve during combustion of waste materials

  6. Experimental investigation on NOx emission characteristics of a new solid fuel made from sewage sludge mixed with coal in combustion.

    Science.gov (United States)

    Zhai, Yunbo; Zhu, Lu; Chen, Hongmei; Xu, Bibo; Li, Caiting; Zeng, Guangming

    2015-02-01

    In this article, a new briquette fuel (SC), which was produced by the mixture of coal fines (25.9%), sewage sludge (60.6%), lignin (4.5%), tannic acid (4.5%) and elemental silicon (4.5%), was provided. Then, in a high temperature electric resistance tubular furnace, the total emissions of NO2 and NO, effects of combustion temperature, air flow rate and heating rate on NOx (NO, NO2) emissions of SC were studied during the combustion of SC; furthermore, effects of additives on hardness were also analysed, and the X-ray photoelectron spectroscopy was applied to investigate the reduced NOx emission mechanism. The research results showed that, compared with the characteristics of briquette fuel (SC0) produced only by the mixture of coal and sewage sludge (the ratio of coal to sewage sludge was the same as that of SC), the Meyer hardness of SC was 12.6% higher than that of SC0 and the emissions of NOx were 27.83% less than that of SC0 under the same combustion conditions. The NOx emissions of SC decreased with the adding of heating rate and increased with the rise of air flow rate. When the temperature was below 1000 °C, the emissions of NOx increased with the elevated temperature, however, further temperature extension will result in a decreasing in emissions of NOx. Furthermore, the X-ray photoelectron spectroscopy results proposed that the possible mechanism for the reduction of NOx emissions was nitrogen and silicon in SC to form the compounds of silicon and nitrogen at high temperatures. © The Author(s) 2015.

  7. Reduction of sludge generation by the addition of support material in a cyclic activated sludge system for municipal wastewater treatment.

    Science.gov (United States)

    Araujo, Moacir Messias de; Lermontov, André; Araujo, Philippe Lopes da Silva; Zaiat, Marcelo

    2013-09-01

    An innovative biomass carrier (Biobob®) was tested for municipal wastewater treatment in an activated sludge system to evaluate the pollutant removal performance and the sludge generation for different carrier volumes. The experiment was carried out in a pilot-scale cyclic activated sludge system (CASS®) built with three cylindrical tanks in a series: an anoxic selector (2.1 m(3)), an aerobic selector (2.5 m(3)) and the main aerobic reactor (25.1 m(3)). The results showed that by adding the Biobob® carrier decreased the MLVSS concentration, which consequently reduced the waste sludge production of the system. Having 7% and 18% (v/v) support material in the aerobic reactor, the observed biomass yield decreased 18% and 36%, respectively, relative to the reactor operated with suspended biomass. The addition of media did not affect the system's performance for COD and TSS removal. However, TKN and TN removal were improved by 24% and 14%, respectively, using 18% (v/v) carrier. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. An investigation of co-combustion municipal sewage sludge with biomass in a 20kW BFB combustor under air-fired and oxygen-enriched condition.

    Science.gov (United States)

    Kumar, Rajesh; Singh, Ravi Inder

    2017-12-01

    The behavior of municipal sewage sludge (MSS) with biomass (Guar stalks (GS), Mustard Husk (MH), Prosopis Juliflora Wood (PJW)) has been investigated in a 20kW bubbling fluidized bed (BFB) combustor under both air-fired (A-F) and oxygen-enriched (O-E) conditions. The work presented is divided into three parts, first part cover the thermogravimetric analysis (TGA), second part cover the experimental investigation of BFB combustor, and third part covers the ash analysis. TGA was performed with a ratio of 50%MSS/50%biomass (GS, MH, PJW) and results show that 50%MSS/50%GS has highest combustion characteristic factor (CCF). The experimental investigation of BFB combustor was performed for two different ratios of MSS/biomass (50%/50% and 25%/75%) and the combustion characteristics of blends were distinctive under both A-F and O-E condition. Despite 50%MSS/50%GS showing the highest combustion performance in TGA analysis, it formed agglomerates during burning in BFB. Due to this formation of large amount of agglomerates, de-fluidization was observed in the combustor bed after 65-75min in A-F conditions. The rate of de-fluidization increased under O-E condition. The de-fluidization problem disappeared when the share of MSS was reduced to 25%, but small amounts of the agglomerate were still present in the bed. With oxygen enhancement, the combustion efficiency of BFB combustor was improved and flue gasses were found within permissible limit. The maximum conceivable combustion efficiency (97.1%) for BFB combustor was accomplished by using 50% MSS/50%PJW under O-E condition. Results show that a ratio of 25%MSS/75%biomass combusted successfully inside the BFB combustor and extensive work is required for efficient utilization of significant share of MSS with biomass. SEM/EDS analyses were performed for agglomerate produced and for the damaged heater to study the surface morphology and compositions. The elemental heterogeneity of fly ash generated during MSS/biomass combustion

  9. Noise generation by ducted combustion systems. [resonant oscillations

    Science.gov (United States)

    Chiu, H. H.; Plett, E. G.; Summerfield, M.

    1973-01-01

    Analysis of the interaction between a zone of nonsteady combustion and its confining duct shows that resonant type oscillations occur with resulting noise intensities far greater than from corresponding unconfined flame zones. The blading action on the flow through the compressor and turbine of an engine generates discrete frequency noise which, it is found, is enhanced by the response of the combustion zone in between. Ducted combustor experiments verify the predicted resonant type noise, the amplitude and frequency of which are strongly influenced by the duct dimensions and end impedance. A convergent exit nozzle results in stronger internal resonant noise oscillations but also generates a higher jet velocity, with the attendant jet noise which exceeds noise from inside the duct at jet Mach numbers near unity.-

  10. Prevention of Bed Agglomeration Problems in a Fluidized Bed Boiler by Finding the Trigging Value of Sewage Sludge Dosage Added to Combustion of Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Kajsa; Gervind, Pernilla

    2009-07-01

    Agglomeration of bed sand is a common problem during combustion of biofuels with high ash content in fluidized bed boilers. Former studies have shown that co-combustion of biofuels with sewage sludge increases the agglomeration temperature. Sewage sludge has a low heating value and high ash content. It would therefore be better to use sludge as an additive to the combustion than as a co-combusted biofuel. In this study the trigging value of sludge addition to the combustion of some biofuel was investigated. The effect of adding sludge with different precipitation chemicals, iron sulphate and aluminium sulphate, was investigated. The biofuels used for the experiments were bark, refused derived fuel (RDF) and a mixture of wood and straw, 75/25 % on energy basis. All experiments were carried out in a laboratory scale fluidized bed reactor. Analyses of chemical composition of bed sand and SEM/EDX analyses were performed after the combustion. Eventually agglomeration tests were performed in order to find the agglomeration temperature of the samples. Some of the samples sintered during the combustion and were not tested for the agglomeration temperature. SEM/EDX showed that all samples of bed sand contained sand particles with more or less coatings. In some cases the coatings seemed to consist of one dense inner layer and one more porous outer layer. From SEM/EDX and chemical composition analyses it was found that the total amount of phosphorous in the bed sand samples was increased with an increased addition of sludge in all experiments. The concentration of phosphorous was especially higher in the outer layers/coatings. It was also found that elements from the sludge seem to get caught by a sticky layer at the bed sand surface and form a non-sticky or less sticky layer that prevents agglomeration. The total amount of aluminium was increased with an increased addition of sludge for the wood/straw samples, while it increased with an increased amount of combusted fuel for

  11. Tailoring next-generation biofuels and their combustion in next-generation engines

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, John Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wu, Weihua [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Taatjes, Craig A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Scheer, Adam Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Turner, Kevin M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yu, Eizadora T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); O' Bryan, Greg [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Powell, Amy Jo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gao, Connie W. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2013-11-01

    Increasing energy costs, the dependence on foreign oil supplies, and environmental concerns have emphasized the need to produce sustainable renewable fuels and chemicals. The strategy for producing next-generation biofuels must include efficient processes for biomass conversion to liquid fuels and the fuels must be compatible with current and future engines. Unfortunately, biofuel development generally takes place without any consideration of combustion characteristics, and combustion scientists typically measure biofuels properties without any feedback to the production design. We seek to optimize the fuel/engine system by bringing combustion performance, specifically for advanced next-generation engines, into the development of novel biosynthetic fuel pathways. Here we report an innovative coupling of combustion chemistry, from fundamentals to engine measurements, to the optimization of fuel production using metabolic engineering. We have established the necessary connections among the fundamental chemistry, engine science, and synthetic biology for fuel production, building a powerful framework for co-development of engines and biofuels.

  12. Comparative study of cogasification and co-combustion of communal sewage sludge in brown coal fuelled plants; Vergleich der Mitvergasung und Mitverbrennung kommunaler Klaerschlaemme in braunkohlegefeuerten Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Schiffer, H.P.; Bierbaum, K.; Adlhoch, W.; Thomas, G. [Rheinbraun AG, Koeln (Germany)

    1996-12-31

    Co-combustion and cogasification of sewage sludge in brown coal fuelled plants are compared, and an economic assessment is made. (ABI) [Deutsch] Die Mitverbrennung und Mitvergasung von Klaerschlamm in braunkohlegefeuerten Anlagen werden verglichen und auf ihre Wirtschaftlichkeit hin untersucht. (ABI)

  13. Comparative study of two co-combustion concepts for sewage sludge in coal dust furnaces; Vergleich zweier Mitverbrennungskonzepte fuer Klaerschlamm in Kohlestaubfeuerungen

    Energy Technology Data Exchange (ETDEWEB)

    Spliethoff, H.; Gerhardt, T.; Ruediger, H.; Hein, K.R.G. [Stuttgart Univ. (Germany). Inst. fuer Verfahrenstechnik und Dampfkesselwesen

    1996-12-31

    Processes for thermal use of sewage sludge in coal dust furnaces were investigated at the Institute of Chemical Engineering and Boiler Technology (IVD) of Stuttgart university. Direct co-combustion of sewage sludge in coal dust furnaces is a simple concept, but it is useful provided that co-combustion has no negative effects in terms of performance, emissions and residue disposal. Externally dried sewage sludge has a residual water content in the same range as coal dust. The effects of co-combustion are discussed, and the experimentally determined effect in terms of emissions and residues is presented. Pyrolysis of the sewage sludge and use of the resulting gas as a reduction agent for denitrification may reduce negative effects of co-combustion on performance, emissions and residues.(orig) [Deutsch] Am Institut fuer Verfahrenstechnik und Dampfkesselwesen (IVD) der Universitaet Stuttgart werden an Versuchsanlagen verschiedene Verfahren zur thermischen Nutzung von Klaerschlaemmen in Verbindung mit Kohlenstaufeuerungen untersucht. Die direkte Mitverbrennung von Klaerschlamm in Kohlestaubfeuerungen ist ein einfaches Konzept, das dann sinnvoll ist, wenn die Mitverbrennung keine negativen Auswirkungen auf Betrieb, Emissionen und Verwertung der Rueckstaende mit sich bringt. Bei einer externen Trockung weist der Klaerschlamm einen aehnlichen Wassergehalt wie der Auslegungsbrennstoff von Steinkohlenstaubfeuerungen auf. Die moeglichen Auswirkungen der Mitverbrennung von Klaerschlamm werden diskutiert und der im Versuch ermittelte Einfluss auf Emissionen und Reststoffe vogestellt. Durch Vorschaltung einer Pyrolyse des Klaerschlamms und Nutzung des erzeugten Gases als Reduktionsmittel zur Entsticklung kann die Auswirkung der Mitverbrennung auf Betrieb, Emissionen und Reststoffe der Feuerungsanlage vermindert werden. (orig)

  14. Characteristics of electricity generation and biodegradation in tidal river sludge-used microbial fuel cells.

    Science.gov (United States)

    Touch, Narong; Hibino, Tadashi; Nagatsu, Yoshiyuki; Tachiuchi, Kouhei

    2014-04-01

    The electricity generation behavior of microbial fuel cell (MFC) using the sludge collected from the riverbank of a tidal river, and the biodegradation of the sludge by the electricity generation are evaluated. Although the maximum current density (150-300 mA/m(2)) was higher than that of MFC using freshwater sediment (30 mA/m(2)), the output current was greatly restricted by the mass transfer limitation. However, our results also indicate that placing the anode in different locations in the sludge could reduce the mass transfer limitation. After approximately 3 months, the removal efficiency of organic carbon was approximately 10%, demonstrated that MFC could also enhance the biodegradation of the sludge by nearly 10-fold comparing with the natural biodegradation. We also found that the biodegradation could be identified by the behavior of oxygen consumption of the sludge. Importantly, the oxygen consumption of the sludge became higher along with the electricity generation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. 77 FR 441 - Measurement and Control of Combustible Gas Generation and Dispersal

    Science.gov (United States)

    2012-01-05

    ... measurement and control of combustible gas generation and dispersal within a power reactor system. The NRC is...; ] NUCLEAR REGULATORY COMMISSION 10 CFR Parts 50, 52, and 100 Measurement and Control of Combustible Gas... measurement and control of combustible gas generation and dispersal within a reactor system. The Commission is...

  16. Parametric Effect during Power Generation from Sewage Sludge Using Prototype MFC

    Directory of Open Access Journals (Sweden)

    Abdul Rehman Memon

    2015-04-01

    Full Text Available Pakistan like other countries is also faced with energy crisis, for which there is a need to identify indigenous technologies along with renewable energy sources to satisfy the energy footprint of the country. Use of MFC (Microbial Fuel Cell technique is currently a step towards this direction that can play an effective role in solving the dual problems of environmental pollution and energy shortage. In this study, sewage sludge from a wastewater treatment plant was collected and used as a substrate for electricity generation in association with other biomass sources. Effect of relevant parameters such as oxygen flow rate, pH and concentration on voltage generation was also analyzed. The experimental results yielded in voltage generation of 2500 mv/l for sewage sludge in comparison to that obtained using carbon manure (270 mv/l, wastewater (229 mv/l and cow manure (330 mv/l suggesting towards the potential of sewage sludge for power generation.

  17. Studies of MHD generator performance with oxygen enriched coal combustion

    Science.gov (United States)

    Wormhoudt, J.; Yousefian, V.; Kolb, C. E.; Martinez-Sanchez, M.

    1980-07-01

    This paper presents calculations made using the Aerodyne PACKAGE (Plasma Analysis, Chemical Kinetics, and Generator Efficiency) computer code which bear on two questions which arise in connection with choices between oxygen enrichment and air preheating to attain the high combustion temperatures needed for open-cycle, coal-fired MHD power generation. The first question is which method produces the highest enthalpy extraction per unit channel length. The second is, in test facilities intended to study tradeoffs between oxygen enrichment and preheated air, can good generator performance be obtained from the same physical channel for different combustor compositions. The answer to the first question is found to depend on what combustor conditions are taken to be comparable. As for the second question, it is found that operation with channel input from off-design combustor conditions can cause serious problems, which can be partially alleviated by changing the channel load factors.

  18. Electrodialytic treatment for metal removal from sewage sludge ash from fluidized bed combustion

    DEFF Research Database (Denmark)

    Pazos, Marta; Kirkelund, Gunvor Marie; Ottosen, Lisbeth M.

    2010-01-01

    Sewage sludge contains several potentially hazardous compounds such as heavy metals, PCBs, PAHs, etc. However, elements with high agricultural value (P, K or Ca) are also present. During the last years, the fluidized bed sludge combustor (FBSC) is considered an effective and novel alternative...... of electrodialytic treatment, the Cd concentration was reduced to values below the limiting concentration. In all experiments the concentrations of other metals were under limiting values of the Danish legislation. It can be concluded that the electrodialytic treatment is an adequate alternative to reduce the Cd...

  19. Characterization of sewage sludge generated in Rio de Janeiro, Brazil, and perspectives for agricultural recycling

    Directory of Open Access Journals (Sweden)

    Alan Henrique Marques de Abreu

    2017-08-01

    Full Text Available Sanitary sewage collection and treatment is a serious environmental problem in Brazilian cities, as well as the destination of solid waste resulting from this process, i.e. the sewage sludge, a substance rich in organic matter and nutrients, which is normally discarded in landfills. The aim of this study was to characterize the sewage sludge generated in four treatment stations in Rio de Janeiro State, Brazil and check if they meet the legal criteria of the National Environment Council (CONAMA, Resolution No. 375/2006. It also focused on analyzing the perspectives for its agricultural recycling based on the potential demand for main agricultural crops grown in Rio de Janeiro State. Samples from eight sewage sludge lots from four treatment stations located in the metropolitan area of Rio de Janeiro were analyzed. These stations receive and treat only domestic sewage by activated sludge system. For chemical and biological characterization of these lots, representative samples were collected and analyzed according to parameters of CONAMA Resolution No. 375/2006. In order to analyze the perspectives of agricultural recycling of sewage sludge in Rio de Janeiro State, 10 crops with the largest cultivated area in the state were surveyed and analyzed which of them are apt to receive sewage sludge as fertilizer and/or soil amendment. To determine the potential demand for sewage sludge in agriculture, the area occupied by these crops were multiplied by each fertilizer recommendation considering the sewage sludge as fertilizer. The analyzed sludge presented a high content of nutrients and organic matter and was included in the parameters of heavy metals, pathogenic agents, and bacteriological indicators stipulated by CONAMA Resolution No. 375/2006. The agricultural panorama of Rio de Janeiro State is favorable for agricultural recycling of sewage sludge since there is a great potential demand for this residue and, among the 10 agricultural crops with the

  20. Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

    Energy Technology Data Exchange (ETDEWEB)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2011-06-08

    Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate’s beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ~60°C, 80°C, and 95°C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

  1. Mitigation of Hydrogen Gas Generation from the Reaction of Uranium Metal with Water in K Basin Sludge and Sludge Waste Forms

    International Nuclear Information System (INIS)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2011-01-01

    Prior laboratory testing identified sodium nitrate and nitrite to be the most promising agents to minimize hydrogen generation from uranium metal aqueous corrosion in Hanford Site K Basin sludge. Of the two, nitrate was determined to be better because of higher chemical capacity, lower toxicity, more reliable efficacy, and fewer side reactions than nitrite. The present lab tests were run to determine if nitrate's beneficial effects to lower H2 generation in simulated and genuine sludge continued for simulated sludge mixed with agents to immobilize water to help meet the Waste Isolation Pilot Plant (WIPP) waste acceptance drainable liquid criterion. Tests were run at ∼60 C, 80 C, and 95 C using near spherical high-purity uranium metal beads and simulated sludge to emulate uranium-rich KW containerized sludge currently residing in engineered containers KW-210 and KW-220. Immobilization agents tested were Portland cement (PC), a commercial blend of PC with sepiolite clay (Aquaset II H), granulated sepiolite clay (Aquaset II G), and sepiolite clay powder (Aquaset II). In all cases except tests with Aquaset II G, the simulated sludge was mixed intimately with the immobilization agent before testing commenced. For the granulated Aquaset II G clay was added to the top of the settled sludge/solution mixture according to manufacturer application directions. The gas volumes and compositions, uranium metal corrosion mass losses, and nitrite, ammonia, and hydroxide concentrations in the interstitial solutions were measured. Uranium metal corrosion rates were compared with rates forecast from the known uranium metal anoxic water corrosion rate law. The ratios of the forecast to the observed rates were calculated to find the corrosion rate attenuation factors. Hydrogen quantities also were measured and compared with quantities expected based on non-attenuated H2 generation at the full forecast anoxic corrosion rate to arrive at H2 attenuation factors. The uranium metal

  2. Hard sludge and denting in the secondary side of PWR steam generators

    International Nuclear Information System (INIS)

    Fernández-Saavedra, R.; Fernández-Díaz, M.; Gómez-Mancebo, M.B.; Quejido-Cabezas, A.J.; Diego, G. de; Gómez-Briceño, D.

    2014-01-01

    The gradual corrosion of PWR (Pressurized Water Reactor) feedwater, condensate and drain systems results in the inevitably liberation and transport of corrosion products. In addition, other contaminants and impurities are introduced with the makeup water, auxiliary feedwater and by condenser leaks. All these compounds can eventually be incorporated into the secondary side of the steam generators (SGs) and transformed into deposits on the SG surfaces, causing the degradation of the thermal performance of the plant and lowering its achievable electrical output. These deposits are found as scale on tube surfaces, blockages in tube support flow passages and sludge piles on the tube sheet and the tube support plate crevices. Among all these deposits, sludge piles consolidating and hardening on the tube sheet and the tube support plate crevices are especially detrimental due to tube deformation or denting that can promote stress corrosion cracking (SCC). Hard sludge accumulation on the tube sheet, tube denting and some SCC have been found in Spanish nuclear power plants with Siemens KWU 61W/D3 steam generators. In this work, we purpose a model for the tube denting production as consequence of the consolidation and hardening of the sludge piles accumulated on the tube sheet of the steam generator throughout data obtained from the more recent operating cycles of these plants i.e., chemical characterization of the sludge and denting evolution. (author)

  3. Removal of secondary sludge from steam generators used in French 900 class nuclear power plants

    International Nuclear Information System (INIS)

    Lebouc, B.

    1982-09-01

    The objective is to remove magnetite deposits which have formed on a steam generator tubesheet during plant operation. The deposits are separated from the tubesheet by spraying water at high pressure (about 200 bar at lance nozzle outlets) on each tube bundle ligament, i.e. the spaces between steam generator tubes. The water is recovered in suction lines and then filtered in two seperate units. The residue obtained after settling is removed in the form of solid waste. This paper presents the sludge lancing technique (spray lances, sludge recovery, liquid waste, cooling). A typical operating sequence is detailed (duration, personnel). Specifications for the equipment used are given

  4. Increased power generation from primary sludge by a submersible microbial fuel cell and optimum operational conditions

    DEFF Research Database (Denmark)

    Vologni, Valentina; Kakarla, Ramesh; Angelidaki, Irini

    2013-01-01

    Microbial fuel cells (MFCs) have received attention as a promising renewable energy technology for waste treatment and energy recovery. We tested a submersible MFC with an innovative design capable of generating a stable voltage of 0.250 ± 0.008 V (with a fixed 470 Ω resistor) directly from primary...... sludge. In a polarization test, the maximum power density was 0.18 W/m2 at a current density of 0.8 A/m2 with an external resistor of 300 Ω. The anodic solution of the primary sludge needs to be adjusted to a pH 7 for high power generation. The modified primary sludge with an added phosphate buffer...

  5. Gas Generation from K East Basin Sludges and Irradiated Metallic Uranium Fuel Particles Series III Testing

    International Nuclear Information System (INIS)

    Schmidt, Andrew J.; Delegard, Calvin H.; Bryan, Samuel A.; Elmore, Monte R.; Sell, Rachel L.; Silvers, Kurt L.; Gano, Susan R.; Thornton, Brenda M.

    2003-01-01

    The path forward for managing of Hanford K Basin sludge calls for it to be packaged, shipped, and stored at T Plant until final processing at a future date. An important consideration for the design and cost of retrieval, transportation, and storage systems is the potential for heat and gas generation through oxidation reactions between uranium metal and water. This report, the third in a series (Series III), describes work performed at the Pacific Northwest National Laboratory (PNNL) to assess corrosion and gas generation from irradiated metallic uranium particles (fuel particles) with and without K Basin sludge addition. The testing described in this report consisted of 12 tests. In 10 of the tests, 4.3 to 26.4 g of fuel particles of selected size distribution were placed into 60- or 800-ml reaction vessels with 0 to 100 g settled sludge. In another test, a single 3.72-g fuel fragment (i.e., 7150-mm particle) was placed in a 60 ml reaction vessel with no added sludge. The twelfth test contained only sludge. The fuel particles were prepared by crushing archived coupons (samples) from an irradiated metallic uranium fuel element. After loading the sludge materials (whether fuel particles, mixtures of fuel particles and sludge, or sludge-only) into reaction vessels, the solids were covered with an excess of K Basin water, the vessels closed and connected to a gas measurement manifold, and the vessels back-flushed with inert neon cover gas. The vessels were then heated to a constant temperature. The gas pressures and temperatures were monitored continuously from the times the vessels were purged. Gas samples were collected at various times during the tests, and the samples analyzed by mass spectrometry. Data on the reaction rates of uranium metal fuel particles with water as a function of temperature and particle size were generated. The data were compared with published studies on metallic uranium corrosion kinetics. The effects of an intimate overlying sludge layer

  6. Generation of Li combustion aerosols for animal inhalation studies.

    Science.gov (United States)

    Allen, M D; Greenspan, B J; Briant, J K; Hoover, M D

    1986-07-01

    A system was developed for generating Li aerosols to determine the potential health hazards of postulated accidents associated with the use of Li as a fusion reactor blanket or coolant. The aerosol was generated by sweeping Ar through a stainless steel chamber filled with Li metal that was heated inductively to temperatures up to 1300 degrees C. Argon carried the Li vapor into a burning chamber where it was mixed with air. The reaction of Li vapor with air formed an intense white flame that produced typical branched-chain condensation aerosol particles. This system generated well-controlled concentrations up to 2500 mg/m3 for periods of 4 h. The mass median aeordynamic diameter of the aerosol was approximately 0.66 micron with a geometric standard deviation of 1.5. Aerosols could be generated that were greater than 96% Li2O and LiOH, LiOH.H2O, or Li2CO3 by controlling the CO2 and H2O concentrations in the supply air. The system is currently being used to investigate the acute toxicity of Li combustion aerosols in laboratory animals.

  7. Combustion

    CERN Document Server

    Glassman, Irvin

    1987-01-01

    Combustion, Second Edition focuses on the underlying principles of combustion and covers topics ranging from chemical thermodynamics and flame temperatures to chemical kinetics, detonation, ignition, and oxidation characteristics of fuels. Diffusion flames, flame phenomena in premixed combustible gases, and combustion of nonvolatile fuels are also discussed. This book consists of nine chapters and begins by introducing the reader to heats of reaction and formation, free energy and the equilibrium constants, and flame temperature calculations. The next chapter explores the rates of reactio

  8. Combustion of hydrogen-oxygen mixture in electrochemically generated nanobubbles.

    Science.gov (United States)

    Svetovoy, Vitaly B; Sanders, Remko G P; Lammerink, Theo S J; Elwenspoek, Miko C

    2011-09-01

    Ignition of exothermic chemical reactions in small volumes is considered as difficult or impossible due to the large surface-to-volume ratio. Here observation of the spontaneous reaction is reported between hydrogen and oxygen in bubbles whose diameter is smaller than a threshold value around 150 nm. The effect is attributed to high Laplace pressure and to fast dynamics in nanobubbles and is the first indication on combustion in the nanoscale. In this study the bubbles were produced by water electrolysis using successive generation of H(2) and O(2) above the same electrode with short voltage pulses in the microsecond range. The process was observed in a microsystem at current densities >1000 A/cm(2) and relative supersaturations >1000.

  9. Combined Cycle Power Generation Employing Pressure Gain Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Holley, Adam [United Technologies Corporation, East Hartford, CT (United States). Research Center

    2017-05-15

    The Phase I program assessed the potential benefit of applying pressure gain combustion (PGC) technology to a natural gas combined cycle power plant. A conceptual design of the PGC integrated gas turbine was generated which was simulated in a detailed system modeling tool. The PGC integrated system was 1.93% more efficient, produced 3.09% more power, and reduced COE by 0.58%. Since the PGC system used had the same fuel flow rate as the baseline system, it also reduced CO2 emissions by 3.09%. The PGC system did produce more NOx than standard systems, but even with the performanceand cost penalties associated with the cleanup system it is better in every measure. This technology benefits all of DOE’s stated program goals to improve plant efficiency, reduce CO2 production, and reduce COE.

  10. Development of second-generation pressurized fluidized bed combustion process

    Energy Technology Data Exchange (ETDEWEB)

    Wolowodiuk, W.; Robertson, A. [Foster Wheeler Development Corp., Livingston, NJ (United States); Bonk, D. [Dept. of Energy, Morgantown, WV (United States)

    1995-12-01

    Under the sponsorship of the United States Department of Energy, Foster Wheeler Development Corporation, and its team members, Westinghouse, Gilbert/Commonwealth, and the Institute of Gas Technology are developing second-generation pressurized fluidized bed combustion technology capable of achieving net plant efficiency in excess of 45 percent based on the higher heating value of the coal. A three-phase program entails design and costing of a 500 MWe power plant and identification of developments needed to commercialize this technology (Phase 1), testing of individual components (Phase 2), and finally testing these components in an integrated mode (Phase 3). This paper briefly describes the results of the first two phases as well as the progress on the third phase. Since other projects which use the same technology are in construction or in negotiation stages-namely, the Power System Development Facility and the Four Rivers Energy Modernization Projects-brief descriptions of these are also included.

  11. Effects of combustion temperature on air emissions and support fuel consumption in full scale fluidized bed sludge incineration: with particular focus on nitrogen oxides and total organic carbon.

    Science.gov (United States)

    Löschau, Margit

    2018-04-01

    This article describes a pilot test at a sewage sludge incineration plant and shows its results considering the impacts of reducing the minimum combustion temperature from 850°C to 800°C. The lowering leads to an actual reduction of the average combustion temperature by 25 K and a significant reduction in the fuel oil consumption for support firing. The test shall be used for providing evidence that the changed combustion conditions do not result in higher air pollutant emissions. The analysis focusses on the effects of the combustion temperature on nitrogen oxides (NO x ) and total organic carbon emissions. The evaluation of all continuously monitored emissions shows reduced emission levels compared to the previous years, especially for NO x .

  12. Improved technique to remove hardened sludge on top of Steam generator tube sheet

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartl, R.

    2015-07-01

    Since many years the top of Steam Generator tube sheet is cleaned by high pressure water jets. In the standard process a multi-nozzle head is manipulated remote controlled inside the No tube lane. The high pressure water jets are directed between the inter-tube aisles. Inner bundle lancing enhanced the efficiency to remove hardened sludge at low flow areas above the tube sheet to a certain extent. For that the nozzle head is fed between the inner tube aisles thus reducing the work distance to a minimum. AREVA GmbH realized a hydraulic driven toothed blade to considerably raise the removal rate of the hardened sludge. (Author)

  13. Bioelectricity generation and dewatered sludge degradation in microbial capacitive desalination cell.

    Science.gov (United States)

    Meng, Fanyu; Zhao, Qingliang; Na, Xiaolin; Zheng, Zhen; Jiang, Junqiu; Wei, Liangliang; Zhang, Jun

    2017-02-01

    Microbial desalination cell (MDC) is a new approach for the synergy in bioelectricity generation, desalination and organic waste treatment without additional power input. However, current MDC systems cause salt accumulation in anodic wastewater and sludge. A microbial capacitive desalination cell (MCDC) with dewatered sludge as anodic substrate was developed to address the salt migration problem and improve the sludge recycling value by special designed-membrane assemblies, which consisted of cation exchange membranes (CEMs), layers of activated carbon cloth (ACC), and nickel foam. Experimental results indicated that the maximum power output of 2.06 W/m 3 with open circuit voltage (OCV) of 0.942 V was produced in 42 days. When initial NaCl concentration was 2 g/L, the desalinization rate was about 15.5 mg/(L·h) in the first 24 h, indicating that the MCDC reactor was suitable to desalinize the low concentration salt solution rapidly. The conductivity of the anodic substrate decreased during the 42-day operation; the CEM/ACC/Ni assemblies could effectively restrict the salt accumulation in MCDC anode and promote dewatered sludge effective use by optimizing the dewatered sludge properties, such as organic matter, C/N, pH value, and electric conductivity (EC).

  14. Processing of sump sludges at the Commonwealth Edison Byron Nuclear Generating Station

    International Nuclear Information System (INIS)

    Herrmann, D.; Gardner, D.A.; Taylor, E.R. Jr.

    1990-01-01

    A basic criterion for the disposal of radioactive waste by shallow land burial is that the material must not contain free liquids. In addition burial sites' requirements regarding radioactive waste containing oils, even though solidified, are restrictive. At Commonwealth Edison Byron Nuclear Generating Station a methodology for processing treated waste sludges, originating form the turbine building's floor drains was developed and implemented. As a result of this effort, 322 drums of oil and water sludge were processed. A dry cake, i.e., no free liquids, was produced, packaged, and readied for disposal. The dry cake contained less than 2% oil. The liquid phases resulting from the processing of the treated waste sludge were oil (that was to be processed for disposal as non-radioactive) and filtrate containing less than 5 ppm total suspended solids (TSS) and oil/grease. The filtrate TSS was below the Station's National Pollution Discharge Elimination System (NPDES) permit release limits. 4 figs

  15. Combustion intensity and distribution relation to noise generation

    Science.gov (United States)

    Plett, E. G.; Leshner, M. D.; Summerfield, M.

    1975-01-01

    Experiments with several different flame holder geometries were conducted to investigate the degree to which combustion roughness can be altered by altering the flame intensity and flame distribution in a ducted combustion system. The effect of admitting primary air through a plane-slotted or a slotted-swirl vane flame holder was compared and the combustion roughness and noise was contrasted with that obtained with a closed front-end perforated can. The slotted front-end burners produced much smoother burning and less noise than the closed front-end can. No advantage was apparent with swirl vs nonswirl when approximately the same inlet flow distribution was maintained. Preheated inlet air provided somewhat smoother combustion as compared with ambient temperature air. The combustion roughness with methyl alcohol was briefly compared with that of isooctane; indications are that it burns more smoothly, but more detailed studies are needed to substantiate these indications.

  16. Evaluation of electricity generation from ultrasonic and heat/alkaline pretreatment of different sludge types using microbial fuel cells.

    Science.gov (United States)

    Oh, Sang-Eun; Yoon, Joung Yee; Gurung, Anup; Kim, Dong-Jin

    2014-08-01

    This study investigated the effects of different sludge pretreatment methods (ultrasonic vs. combined heat/alkali) with varied sources of municipal sewage sludge (primary sludge (PS), secondary excess sludge (ES), anaerobic digestion sludge (ADS)) on electricity generation in microbial fuel cells (MFCs). Introduction of ultrasonically pretreated sludge (PS, ES, ADS) to MFCs generated maximum power densities of 13.59, 9.78 and 12.67mW/m(2) and soluble COD (SCOD) removal efficiencies of 87%, 90% and 57%, respectively. The sludge pretreated by combined heat/alkali (0.04N NaOH at 120°C for 1h) produced maximum power densities of 10.03, 5.21 and 12.53mW/m(2) and SCOD removal efficiencies of 83%, 75% and 74% with PS, ES and ADS samples, respectively. Higher SCOD by sludge pretreatment enhanced performance of the MFCs and the electricity generation was linearly proportional to the SCOD removal, especially for ES. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Combustion Characteristics of Butane Porous Burner for Thermoelectric Power Generation

    Directory of Open Access Journals (Sweden)

    K. F. Mustafa

    2015-01-01

    Full Text Available The present study explores the utilization of a porous burner for thermoelectric power generation. The porous burner was tested with butane gas using two sets of configurations: single layer porcelain and a stacked-up double layer alumina and porcelain. Six PbSnTe thermoelectric (TE modules with a total area of 54 cm2 were attached to the wall of the burner. Fins were also added to the cold side of the TE modules. Fuel-air equivalence ratio was varied between the blowoff and flashback limit and the corresponding temperature, current-voltage, and emissions were recorded. The stacked-up double layer negatively affected the combustion efficiency at an equivalence ratio of 0.20 to 0.42, but single layer porcelain shows diminishing trend in the equivalence ratio of 0.60 to 0.90. The surface temperature of a stacked-up porous media is considerably higher than the single layer. Carbon monoxide emission is independent for both porous media configurations, but moderate reduction was recorded for single layer porcelain at lean fuel-air equivalence ratio. Nitrogen oxides is insensitive in the lean fuel-air equivalence ratio for both configurations, even though slight reduction was observed in the rich region for single layer porcelain. Power output was found to be highly dependent on the temperature gradient.

  18. Optimal policies for activated sludge treatment systems with multi effluent stream generation

    Directory of Open Access Journals (Sweden)

    Gouveia R.

    2000-01-01

    Full Text Available Most industrial processes generate liquid waste, which requires treatment prior to disposal. These processes are divided into sectors that generate effluents with time dependent characteristics. Each sector sends the effluent to wastewater treatment plants through pumping-stations. In general, activated sludge is the most suitable treatment and consists of equalization, aeration and settling tanks. During the treatment, there is an increase in the mass of microorganisms, which needs to be removed. Sludge removal represents the major operating costs for wastewater treatment plants. The objective of this work is to propose an optimization model to minimize sludge generation using a superstructure in which the streams from pumping-stations can be sent to the equalization tank. In addition, the aeration tank is divided into cells that can be fed in series and parallel. The model relies on mass balances, kinetic equations, and the resulting Nonlinear Programming problem generates the best operational strategy for the system feed streams with a high substrate removal. Reductions of up to 30 % can be achieved with the proposed strategy maintened BOD efficiency removal upper than 98 %.

  19. Characterization of sludge generated from the treatment of sanitary landfill leachate with tannin-based coagulant

    OpenAIRE

    Taluana Delakis Recanello; Amanda Shizuka Fujimura; Carlos de Barros Junior; Lucila Akiko Nagashima

    2010-01-01

    The aim of this study was to characterise the sludge resulting from the leachate treatment generated at sanitary landfill with tannin-based coagulant, denominated Tanfloc SG® supplied by TANAC SA Company. The effluent treatment was performed at pH 7.4 and [Tanfloc SG] = 2700 mg/L, considered as optimum condition in COD and turbidity removal, however. Metal fractionation chemical analyses were done through simple and sequential extractions, with results indicating the solid residue is constit...

  20. Development of KALANS to remove sludge of steam generator

    International Nuclear Information System (INIS)

    Jeong, W. T.; Yang, J. S.; You, G. W.; Sung, G. B.; Kim, B. Y.

    1999-01-01

    CECIL -4 lancing system by Foster-Miller has been used for the secondary side landing of Westinghouse type steam generators (YGN No. 1,2 and Kori No. 1,2,3,4) in Korean nuclear power plants. Shared use of only one lancing system for the 6 nuclear power plants required frequent transportation of the system from Nori to Youngkwang which may cause malfunction of sophisticated control equipment. Sometimes, the overlap in preventive maintenance schedule of nuclear power plants prevented the plant maintenance personnel from doing sufficient lancing work. Purchasing a new lancing system may be a candidate for this problem, but the price tag is surprisingly high. Furthermore, prompt maintenance was another serious problem because the manufacturer is far away in a foreign country. Last year, the steam generator of Kori No. 1 was changed to Δ60. The difference in the tube arrangement of the new steam generator made it impossible to use the CECIL system. Sufficient technological background of our development team and the conclusion that the development project is economically feasible made us to commence the design and fabrication of 'KEPCO Advanced LANcing System - KALANS.' This paper presents the state of the art on lancing system and the developed concept and design of KALANS

  1. Bioelectrochemical desalination and electricity generation in microbial desalination cell with dewatered sludge as fuel.

    Science.gov (United States)

    Meng, Fanyu; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Guodong; Fan, Qingxin; Wei, Liangliang; Ding, Jing; Zheng, Zhen

    2014-04-01

    Microbial desalination cells (MDCs) with common liquid anodic substrate exhibit a slow startup and destructive pH drop, and abiotic cathodes have high cost and low sustainability. A biocathode MDC with dewatered sludge as fuel was developed for synergistic desalination, electricity generation and sludge stabilization. Experimental results indicated that the startup period was reduced to 3d, anodic pH was maintained between 6.6 and 7.6, and high stability was shown under long-term operation (300d). When initial NaCl concentrations were 5 and 10g/L, the desalinization rates during stable operation were 46.37±1.14% and 40.74±0.89%, respectively. The maximum power output of 3.178W/m(3) with open circuit voltage (OCV) of 1.118V was produced on 130d. After 300d, 25.71±0.15% of organic matter was removed. These results demonstrated that dewatered sludge was an appropriate anodic substrate to enhance MDC stability for desalination and electricity generation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Characterization of sludge generated from the treatment of sanitary landfill leachate with tannin-based coagulant

    Directory of Open Access Journals (Sweden)

    Taluana Delakis Recanello

    2010-09-01

    Full Text Available The aim of this study was to characterise the sludge resulting from the leachate treatment generated at sanitary landfill with tannin-based coagulant, denominated Tanfloc SG® supplied by TANAC SA Company. The effluent treatment was performed at pH 7.4 and [Tanfloc SG] = 2700 mg/L, considered as optimum condition in COD and turbidity removal, however. Metal fractionation chemical analyses were done through simple and sequential extractions, with results indicating the solid residue is constituted by 29% of amorphous oxide, 28% of final residue, 22% of crystalline oxide and 21% of exchangeable fraction. The leaching tests have shown the sludge originated by Tanfloc SG® treatment is classified as Class I residue - considered dangerous, according to Brazilian legislation (NBR 10.004/2004 - ABNT, indicating that such residues need to be treated and must be disposed in industrial landfills, for being a hazardous material due to its toxicity.

  3. Pollutants generated by the combustion of solid biomass fuels

    CERN Document Server

    Jones, Jenny M; Ma, Lin; Williams, Alan; Pourkashanian, Mohamed

    2014-01-01

    This book considers the pollutants formed by the combustion of solid biomass fuels. The availability and potential use of solid biofuels is first discussed because this is the key to the development of biomass as a source of energy.This is followed by details of the methods used for characterisation of biomass and their classification.The various steps in the combustion mechanisms are given together with a compilation of the kinetic data. The chemical mechanisms for the formation of the pollutants: NOx, smoke and unburned hydrocarbons, SOx, Cl compounds, and particulate metal aerosols

  4. Investigation of sulfur forms and transformation during the co-combustion of sewage sludge and coal using X-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Li Peisheng; Hu Yi; Yu Wan; Yue Yanan; Xu Qiao; Hu Song; Hu Niansu; Yang Jun

    2009-01-01

    X-ray photoelectron spectroscopy was used to investigate the characteristics and evolution of sulfur (S) in mixtures of bituminous coal and sewage sludge (SS) and their chars during isothermal combustion. Five groups of mixtures with SS content of 0%, 10%, 20%, 30% and 100%, were examined at different burn-off ratios (β) of 0, 30%, 50%, 70% and 100%. The S in the coal mainly exist as the forms of mercaptan (S1), sulfide (S2), thiophene (S3), sulfoxide (S4), sulfone (S5) and sulfate (S6). During the coal combustion process, the content of S1 and S2 decreased, while that of S3 and S5 increased in the early stage and decreased in the late stage. The S4 content increased throughout the entire process of combustion. Small amount of S6 was detected, showing a fluctuated pattern. The trend of S1, S2, S5 and S6 in SS was alike with that in coal, whereas S4 decreased at the end of combustion. The changing process of S3 in SS was opposite to that of coal, while the composition of S in the mixtures resulted from the mixing of coal and SS. The transformation of each functional group during co-combustion were correlated with their transformation characteristics during the mono-combustion of coal and SS, and no obvious interaction was observed, which demonstrated that the coal-origin and SS-origin sulfur in mixtures kept their own characteristics in the combustion. SS may accumulate on the solid surface as α increase, resulting its significant influence on the evolution of each form of S. When α was low, most of the S-contained functional groups presented the characteristics of coal. The percentage of coal-origin functional groups declined as α increased. The transforming trends of most functional groups were similar with that of SS when α reached 30%.

  5. Utilisation of fly ash for the management of heavy metal containing primary chemical sludge generated in a leather manufacturing industry

    Energy Technology Data Exchange (ETDEWEB)

    Sekaran, G.; Rao, B.P.; Ghanamani, A.; Rajamani, S. [Central Leather Research Institute, Chennai (India). Dept. of Environmental Technology

    2003-07-01

    The present study aims at disposal of primary chemical sludge generated in the tanning industry by solidification and stabilization process using flyash generated from thermal power plant along with binders and also on evaluating the leachability of heavy metal from the solidified product. The primary chemical sludge containing heavy metals iron and chromium were obtained from a garment leather manufacturing company at Chennai in India. The sludge was dried in open environment and it was powdered to fine size in a grinder. Binding increases stabilization of heavy metal in calcined sludge with refractory binders such as clay, fly ash, lime and ordinary Portland cement. Fly ash can be considered as the additional binder for producing stronger bricks, with high metal fixation efficiency, and minimum rate of removal of heavy metal and minimum diffusion co-efficient. 15 refs., 5 figs., 5 tabs.

  6. A numerical investigation of the entropy generation in and thermodynamic optimization of a combustion chamber

    International Nuclear Information System (INIS)

    Arjmandi, H.R.; Amani, E.

    2015-01-01

    In this study, we are simulating the turbulent combustion of a mixed bluff-body swirl stabilized flame in a gas turbine combustion chamber and investigating the effects of different parameters, including the swirl number, distance between the air and fuel nozzle which is called bluff size, equivalence ratio, inlet fuel flow rate, and the inlet air velocity, on the entropy generation. We perform the process of the design of the combustion chamber by proposing the optimal value of each parameter based on the EGM (entropy generation minimization) method under the two maximum allowable temperature and size constraints. Two common methods of entropy generation calculation, one based on the overall entropy balance on a system and the other based on the local entropy generation rate calculation, are used and compared in this study. Our results show that the deviation between the total entropy generations calculated by the two methods is 6.4% in average which is an acceptable error in turbulent combustion simulations. Also, the two opposing factors, namely chemical reaction and heat transfer, have the main contribution to the total entropy generation. - Highlights: • We perform the design of a combustion chamber using CFD and based on the EGM method. • We use and compare two methods for computing the total entropy generation. • We also study the entropy generation due to different phenomena separately. • Reaction and heat transfer have the dominant contribution to the entropy generation

  7. Bioelectrochemically-assisted anaerobic composting process enhancing compost maturity of dewatered sludge with synchronous electricity generation.

    Science.gov (United States)

    Yu, Hang; Jiang, Junqiu; Zhao, Qingliang; Wang, Kun; Zhang, Yunshu; Zheng, Zhen; Hao, Xiaodi

    2015-10-01

    Bioelectrochemically-assisted anaerobic composting process (AnCBE) with dewatered sludge as the anode fuel was constructed to accelerate composting of dewatered sludge, which could increase the quality of the compost and harvest electric energy in comparison with the traditional anaerobic composting (AnC). Results revealed that the AnCBE yielded a voltage of 0.60 ± 0.02 V, and total COD (TCOD) removal reached 19.8 ± 0.2% at the end of 35 d. The maximum power density was 5.6 W/m(3). At the end of composting, organic matter content (OM) reduction rate increased to 19.5 ± 0.2% in AnCBE and to 12.9 ± 0.1% in AnC. The fuzzy comprehensive assessment (FCA) result indicated that the membership degree of class I of AnCBE compost (0.64) was higher than that of AnC compost (0.44). It was demonstrated that electrogenesis in the AnCBE could improve the sludge stabilization degree, accelerate anaerobic composting process and enhance composting maturity with bioelectricity generation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Two-stage pretreatment of excess sludge for electricity generation in microbial fuel cell.

    Science.gov (United States)

    Zhang, Yi; Zhao, Yang-Guo; Guo, Liang; Gao, Mengchun

    2018-01-12

    Thermophiles hydrolysis and acidogens fermentation were sequentially adopted to pretreat excess sludge for microbial fuel cell (MFC) electricity production. The results indicated that MFC fed with the thermophiles-acidogens pretreated sludge (MFC AB), reached a higher removal of ammonia nitrogen than the MFC fed with the heating hydrolysis and acidogens fermentation pretreated sludge (MFC NB). However, compared with the MFC AB, MFC NB presented a better performance for removal of soluble chemical oxygen demand (SCOD) (90.08%) and protein (82.42%). As for the electricity production, MFC NB obtained higher voltage of 0.632 V and maximum power density with 1.05 W/m 3 while MFC AB reached maximum voltage of 0.373 V and maximum power density of 0.58 W/m 3 . Bacterial 16S rRNA-based molecular microbial techniques showed that microbial communities on both MFC anode biofilms was diverse and different. The cooperation of fermentation bacteria and electricigen Shewanella baltica in the MFC NB may have contributed towards the improvement of electricity generation.

  9. Benefits of integrating chemical and mechanical cleaning processes for steam generator sludge removal

    International Nuclear Information System (INIS)

    Varrin, R.D.; Ferriter, A.M.; Oliver, T.W.; Le Surf, J.E.

    1992-01-01

    This paper discusses the benefits of performing in-bundle tubesheet lancing in conjunction with chemical cleaning of PWR and PHWR steam generators in which a hard sludge pile is known to exist. The primary benefits of in-bundle lancing are to: (1) increase the exposed area of the sludge pile by cutting furrows in the surface thereby enhancing dissolution of sludge, (2) reduce the volume of solvents required since material removed by lancing does not have to be dissolved chemically, (3) improve rinsing and removal of residual solvent between iron and copper dissolution steps, and (4) allow for verification of process effectiveness by providing high quality in-bundle visual inspection. The reduction in solvent volumes can lead to a significant reduction in solvent costs and waste processing. A case study which includes an economic evaluation for a combined chemical and mechanical cleaning shows a potential cost saving of up to US$ 300,000 over use of chemical cleaning alone. 14 refs., 2 tabs., 2 figs

  10. Advanced Combustion Systems for Next Generation Gas Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Joel Haynes; Jonathan Janssen; Craig Russell; Marcus Huffman

    2006-01-01

    Next generation turbine power plants will require high efficiency gas turbines with higher pressure ratios and turbine inlet temperatures than currently available. These increases in gas turbine cycle conditions will tend to increase NOx emissions. As the desire for higher efficiency drives pressure ratios and turbine inlet temperatures ever higher, gas turbines equipped with both lean premixed combustors and selective catalytic reduction after treatment eventually will be unable to meet the new emission goals of sub-3 ppm NOx. New gas turbine combustors are needed with lower emissions than the current state-of-the-art lean premixed combustors. In this program an advanced combustion system for the next generation of gas turbines is being developed with the goal of reducing combustor NOx emissions by 50% below the state-of-the-art. Dry Low NOx (DLN) technology is the current leader in NOx emission technology, guaranteeing 9 ppm NOx emissions for heavy duty F class gas turbines. This development program is directed at exploring advanced concepts which hold promise for meeting the low emissions targets. The trapped vortex combustor is an advanced concept in combustor design. It has been studied widely for aircraft engine applications because it has demonstrated the ability to maintain a stable flame over a wide range of fuel flow rates. Additionally, it has shown significantly lower NOx emission than a typical aircraft engine combustor and with low CO at the same time. The rapid CO burnout and low NOx production of this combustor made it a strong candidate for investigation. Incremental improvements to the DLN technology have not brought the dramatic improvements that are targeted in this program. A revolutionary combustor design is being explored because it captures many of the critical features needed to significantly reduce emissions. Experimental measurements of the combustor performance at atmospheric conditions were completed in the first phase of the program

  11. Influence of catalysts on co-combustion of sewage sludge and water hyacinth blends as determined by TG-MS analysis.

    Science.gov (United States)

    Huang, Limao; Xie, Candie; Liu, Jingyong; Zhang, Xiaochun; Chang, KenLin; Kuo, Jiahong; Sun, Jian; Xie, Wuming; Zheng, Li; Sun, Shuiyu; Buyukada, Musa; Evrendilek, Fatih

    2018-01-01

    Effects of the three metal carbonates (K 2 CO 3 , Na 2 CO 3 , and MgCO 3 ) were quantified on catalytic co-combustion of the sewage sludge and water hyacinth (SW) blend using a thermogravimetric-mass spectrometric (TG-MS) analysis and kinetics modeling. The main dominating steps of the catalysts were the organic volatile matter release and combustion stage. Weighted mean values of activation energy (E m ) were estimated at 181.18KJ·mol -1 , 199.76KJ·mol -1 , 138.76KJ·mol -1 , and 177.88KJ·mol -1 for SW, SW+5% K 2 CO 3 , SW+5% Na 2 CO 3 , and SW+5% MgCO 3 , respectively. The lowest E m occurred with SW+5% Na 2 CO 3 . Overall, catalyst effect on co-combustion appeared to be negligible as indicated by Gibbs free energy (ΔG). The normalized intensities of SW+MgCO 3 were strongest. The addition of Na 2 CO 3 and MgCO 3 to SW increased flue gases emissions (CO 2 , NO 2 , SO 2 , HCN, and NH 3 ) of SW, whereas the addition of K 2 CO 3 to SW reduced flue gases emissions from the entire combustion process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A Review of LOX/Kerosene Combustion Instability in American and Russian Combustion Devices in Application to Next-Generation Launch Technology

    Science.gov (United States)

    Rocker, Marvin; Nesman, Tomas E.; Hulka, James R.; Dougherty, N. Sam

    2003-01-01

    The Next-Generation Launch Technology (NGLT) project was introduced with its objectives. To meet the objectives, NASA has directed aerospace industry to perform advances and risk reduction of relevant technologies, including propulsion. Originally, the propulsion industry focused on producing both LOWLH2 and LOWkerosene flight engine technology demonstrators. These flight engine technology demonstrators were briefly reviewed. NASA recently redirected this focus to Lowkerosene only. Discussion of LOWkerosene combustion devices was and is prefaced by grave concerns about combustion instability. These concerns have prompted a review of LOWkerosene combustion instability in American and Russian combustion devices. In the review of the Russian propulsion industry's experience in eliminating LOWkerosene combustion instabilities, the history of principal Russian rocket scientists and their role in the development of LOXkerosene combustion devices is presented. The innovative methods implemented by the Russians of eliminations combustion instabilities in LOXkerosene combustion devices were reviewed. The successful elimination of these combustion instabilities has resulted in two generations of Russian-produced, high-performance LOWkerosene combustion devices.

  13. Basic study on the generation of RF plasmas in premixed oxy-combustion with methane

    International Nuclear Information System (INIS)

    Osaka, Yugo; Razzak, M.A.; Kobayashi, Noriyuki; Ohno, Noriyasu; Takamura, Shuichi; Uesugi, Yoshihiko

    2010-01-01

    Oxy-combustion generates a high temperature field (above 3000 K), which is applied to next generation power plants and high temperature industrial technologies because of N 2 free processes. However, the combustion temperature is so high that the furnace wall may be fatally damaged. In addition, it is very difficult to control the heat flux and chemical species' concentrations because of rapid chemical reactions. We have developed a new method for controlling the flame by electromagnetic force on this field. In this paper, we experimentally investigated the power coupling between the premixed oxy-combustion with methane and radio frequency (RF) power through the induction coil. By optimizing the power coupling, we observed that the flame can absorb RF power up to 1.5 kW. Spectroscopic measurements also showed an increase in the emission intensity from OH radicals in the flame, indicating improved combustibility. (author)

  14. Indirect Combustion Noise: Noise Generation by Accelerated Vorticity in a Nozzle Flow

    Directory of Open Access Journals (Sweden)

    Nancy Kings

    2010-09-01

    Full Text Available The noise generation by accelerated vorticity waves in a nozzle flow was investigated in a model experiment. This noise generation mechanism belongs, besides entropy noise, to the indirect combustion noise phenomena. Vorticity as well as entropy fluctuations, originating from the highly turbulent combustion zone, are convected with the flow and produce noise during their acceleration in the outlet nozzle of the combustion chamber. In the model experiment, noise generation of accelerated vorticity fluctuations was achieved. The vorticity fluctuations in the tube flow were produced by injecting temporally additional air into the mean flow. As the next step, a parametric study was conducted to determine the major dependencies of the so called vortex noise. A quadratic dependency of the vortex noise on the injected air amount was found. In order to visualise and classify the artificially generated vorticity structures, planar velocity measurements have been conducted applying Particle Image Velocimetry (PIV.

  15. Study of Second Generation Biofuels in Internal Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Kannan, Dhandapani

    2012-07-01

    fuel, vis-a-vis neat diesel fuel (DF). The CO, THC, smoke and TPM emissions were reduced significantly, while NOx emissions were somewhat higher with BD blended fuels compared to neat FT fuel. The reductions in CO, THC, smoke and TPM emissions with BD blends were mainly due to the oxygen content in the BD blended fuel, while the increases in NOx emissions with BD fuels were due to advances in injection timing, higher percentages of fatty acids with double bonds in the carbon chain and higher heat release in the pre-mixed combustion. Secondly, a four-stroke, single-cylinder, naturally-aspirated (NA), direct-injection (DI) diesel engine with 8 BHP at 1500 rpm coupled with water-cooled, eddy current dynamometer was used for the experiments. Ethanol (5% by volume) was injected into the intake manifold by the port injection method with the assistance of a mechanical fuel injection pump. Therefore, the volumetric blending percentages of ethanol, BD and diesel fuels (E:D:JME) are (0:100:0), (5:95:0), (5:75:20), (5:55:40), (5:35:60), (5:15:80) (5:0:95) and (0:0:100) respectively. Ethanol pre-mixed with intake air, assisted in improving combustion in both diesel and the JME blends. The addition of ethanol to high-viscosity Jatropha methyl ester (JME) through port injection is investigated in order to determine its effect on the fuels viscosity and thereby on the diesel engine performance. In addition to viscosity alteration, the impact of ethanol addition on combustion characteristics such as combustion duration, ignition delay and emissions levels from diesel engines fuelled with blends of ethanol, diesel and JME was studied in particular. It was found that blending of oxygenated fuels with diesel modifies the chemical structure and physical properties which in turn, alter the engines operating conditions, combustion parameters and emissions levels. However, the injection of only 5% ethanol through port injection allows for up to 25% blending of diesel with biofuels, while

  16. Toxic combustion by-products: Generation, separation, cleansing, containment

    Energy Technology Data Exchange (ETDEWEB)

    Kephart, W.; Eger, K. [Foster-Wheeler Environmental Corp., Oak Ridge, TN (United States); Angelo, F. [Resource Energy Corp., Fort Smith, AR (United States); Clemens, M.K. [Argonne National Lab., IL (United States)

    1995-12-31

    Focus of this paper is on diagnosis, control, and containment of potentially toxic combustion byproducts when mixed wastes are treated at elevated temperatures. Such byproducts fall into several categories: acid gases, particulates, metals, organics. Radionuclides are treated as a subset of metals, while organics are divided into two subclasses: products of incomplete combustion, and principal organic hazardous constituents. An extended flue gas cleaning system is described which can be used to contain potentially toxic organic emissions and recycle the hazrdous materials for further treatment; it uses oxygen rather than air to reduce total quantities of emissions, improve efficiency of oxidation, and minimize NOx emissions. Flue gas recycling is used for cooling and for containing all potentially toxic emissions. Three thermal treatment unit operations are used in series for more effective process control; three emission separation and containment unit operations are also used in series in the toxic emission containment system. Real time diagnostic hardware/software are used. Provision is made for automatic storage, separation of hazardous materials, commodity regeneration, and recycling of potentially harmful constituents. The greenhouse gas CO2 is recovered and not emitted to the atmosphere.

  17. Electricity generation from fermented primary sludge using single-chamber air-cathode microbial fuel cells

    KAUST Repository

    Yang, Fei

    2013-01-01

    Single-chamber air-cathode microbial fuel cells (MFCs) were used to generate electricity from fermented primary sludge. Fermentation (30°C, 9days) decreased total suspended solids (26.1-16.5g/L), volatile suspended solids (24.1-15.3g/L) and pH (5.7-4.5), and increased conductivity (2.4-4.7mS/cm), soluble COD (2.66-15.5g/L), and volatile fatty acids (1.9-10.1g/L). To lower the COD and increase pH, fermentation supernatant was diluted with primary effluent before being used in the MFCs. The maximum power density was 0.32±0.01W/m2, compared to 0.24±0.03W/m2 with only primary effluent. Power densities were higher with phosphate buffer added to the supernatant (1.03±0.06W/m2) or the solution (0.87±0.05W/m2). Coulombic efficiencies ranged from 18% to 57%, and sCOD removals from 84% to 94%. These results demonstrated that sludge can effectively be used for power generation when fermented and then diluted with only primary effluent. © 2012 Elsevier Ltd.

  18. Energy generation in a Microbial Fuel Cell using anaerobic sludge from a wastewater treatment plant

    Directory of Open Access Journals (Sweden)

    Vinicius Fabiano Passos

    Full Text Available ABSTRACT In microbial fuel cells (MFCs, the oxidation of organic compounds catalyzed by microorganisms (anode generates electricity via electron transfer to an external circuit that acts as an electron acceptor (cathode. Microbial fuel cells differ in terms of the microorganisms employed and the nature of the oxidized organic compound. In this study, a consortium of anaerobic microorganisms helped to treat the secondary sludge obtained from a sewage treatment plant. The microorganisms were grown in a 250 mL bioreactor containing a carbon cloth. The reactor was fed with media containing acetate (as the carbon source for 48 days. Concomitantly, the electrochemical data were measured with the aid of a digital multimeter and data acquisition system. At the beginning of the MFC operation, power density was low, probably due to slow microorganism growth and adhesion. The power density increased from the 15th day of operation, reaching a value of 13.5 μW cm–2 after ca. 24 days of operation, and remained stable until the end of the process. Compared with data in the literature, this power density value is promising; improvements in the MFC design and operation could increase this value even further. The system investigated herein employed excess sludge as a biocatalyst in an MFC. This opens up the possibility of using organic acids and/or carbohydrate-rich effluents to feed MFCs, and thereby provide simultaneous effluent treatment and energy generation.

  19. Aerosol generation by oxidation and combustion of plutonium and its compounds: literature survey

    International Nuclear Information System (INIS)

    Ballereau, P.

    1987-09-01

    Generation of aerosols by oxidation or combustion is one of the greatest risks due to plutonium. A review is made of the most interesting documents available on this topic. Following a brief study of plutonium oxydation conditions, characteristics of aerosols generated by accidents of fires involving metallic Pu and some of its compounds are assessed. Nuclear weapons are not included in this review [fr

  20. Dioxinlike properties of a trichloroethylene combustion-generated aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Villalobos, S.A.; Anderson, M.J.; Hinton, D.E. [Univ. of California, Davis, CA (United States)] [and others

    1996-07-01

    Conventional chemical analyses of incineration by-products identify compounds of known toxicity but often fail to indicate the presence of other chemicals that may pose health risks. In a previous report, extracts from soot aerosols formed during incomplete combustion of trichloroethylene (TCE) and pyrolysis of plastics exhibited a dioxinlike response when subjected to a keratinocyte assay. To verify this dioxinlike effect, the complete extract, its polar and nonpolar fractions, some containing primarily halogenated aromatic hydrocarbons, were evaluated for toxicity using an embryo assay, for antiestrogenicity using primary liver cell cultures, and for the ability to transform the aryl hydrocarbon receptor into its DNA binding form using liver cytosol in a gel retardation assay. Each of these assays detect dioxinlike effects. Medaka (Oryzias latipes) embryos and primary liver cell cultures of rainbow trout (Oncorhynchus mykiss) were exposed to concentrations of extract ranging from 0.05 to 45 {mu}g/l. 67 refs., 7 figs., 3 tabs.

  1. Third-harmonic generation and scattering in combustion flames using a femtosecond laser filament.

    Science.gov (United States)

    Zang, Hong-Wei; Li, He-Long; Su, Yue; Fu, Yao; Hou, Meng-Yao; Baltuška, Andrius; Yamanouchi, Kaoru; Xu, Huailiang

    2018-02-01

    Coherent radiation in the ultraviolent (UV) range has high potential applicability to the diagnosis of the formation processes of soot in combustion because of the high scattering efficiency in the UV wavelength region, even though the UV light is lost largely by the absorption within the combustion flames. We show that the third harmonic (TH) of a Ti:sapphire 800 nm femtosecond laser is generated in a laser-induced filament in a combustion flame and that the conversion efficiency of the TH varies sensitively by the ellipticity of the driver laser pulse but does not vary so much by the choice of alkanol species introduced as fuel for the combustion flames. We also find that the TH recorded from the side direction of the filament is the Rayleigh scattering of the TH by soot nanoparticles within the flame and that the intensity of the TH varies depending on the fuel species as well as on the position of the laser filament within the flame. Our results show that a remote and in situ measurement of distributions of soot nanoparticles in a combustion flame can be achieved by Rayleigh scattering spectroscopy of the TH generated by a femtosecond-laser-induced filament in the combustion flame.

  2. Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

    International Nuclear Information System (INIS)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2010-01-01

    Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

  3. Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

    2010-01-29

    Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

  4. Co-combustion of sewage sludge and coffee grounds under increased O2/CO2atmospheres: Thermodynamic characteristics, kinetics and artificial neural network modeling.

    Science.gov (United States)

    Chen, Jiacong; Xie, Candie; Liu, Jingyong; He, Yao; Xie, Wuming; Zhang, Xiaochun; Chang, Kenlin; Kuo, Jiahong; Sun, Jian; Zheng, Li; Sun, Shuiyu; Buyukada, Musa; Evrendilek, Fatih

    2018-02-01

    (Co-)combustion characteristics of sewage sludge (SS), coffee grounds (CG) and their blends were quantified under increased O 2 /CO 2 atmosphere (21, 30, 40 and 60%) using a thermogravimetric analysis. Observed percentages of CG mass loss and its maximum were higher than those of SS. Under the same atmospheric O 2 concentration, both higher ignition and lower burnout temperatures occurred with the increased CG content. Results showed that ignition temperature and comprehensive combustion index for the blend of 60%SS-40%CG increased, whereas burnout temperature and co-combustion time decreased with the increased O 2 concentration. Artificial neural network was applied to predict mass loss percent as a function of gas mixing ratio, heating rate, and temperature, with a good agreement between the experimental and ANN-predicted values. Activation energy in response to the increased O 2 concentration was found to increase from 218.91 to 347.32 kJ·mol -1 and from 218.34 to 340.08 kJ·mol -1 according to the Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa methods, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Thermodynamics and kinetics parameters of co-combustion between sewage sludge and water hyacinth in CO2/O2 atmosphere as biomass to solid biofuel.

    Science.gov (United States)

    Huang, Limao; Liu, Jingyong; He, Yao; Sun, Shuiyu; Chen, Jiacong; Sun, Jian; Chang, KenLin; Kuo, Jiahong; Ning, Xun'an

    2016-10-01

    Thermodynamics and kinetics of sewage sludge (SS) and water hyacinth (WH) co-combustion as a blend fuel (SW) for bioenergy production were studied through thermogravimetric analysis. In CO2/O2 atmosphere, the combustion performance of SS added with 10-40wt.% WH was improved 1-1.97 times as revealed by the comprehensive combustion characteristic index (CCI). The conversion of SW in different atmospheres was identified and their thermodynamic parameters (ΔH,ΔS,ΔG) were obtained. As the oxygen concentration increased from 20% to 70%, the ignition temperature of SW decreased from 243.1°C to 240.3°C, and the maximum weight loss rate and CCI increased from 5.70%·min(-1) to 7.26%·min(-1) and from 4.913%(2)·K(-3)·min(-2) to 6.327%(2)·K(-3)·min(-2), respectively, which corresponded to the variation in ΔS and ΔG. The lowest activation energy (Ea) of SW was obtained in CO2/O2=7/3 atmosphere. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Developments in, and environmental impacts of, electricity generation from municipal solid waste and landfill gas combustion

    International Nuclear Information System (INIS)

    Porteous, A.

    1993-01-01

    The 1991 NFFO allocations for renewable energy generation are reviewed with emphasis on electricity from municipal solid waste (MSW) and landfill gas (LFG) combustion tranches. The implications of materials recovery on the calorific value of MSW are considered, as are the environmental impacts of both MSW and LFG combustion with special reference to air pollutant emissions. The performance and economics of state of the art incineration and LFG power generating plants are examined. It is shown that energy recovery from these wastes can be both cost effective and environmentally desirable. (Author)

  7. Energy potential and alternative usages of biogas and sludge from UASB reactors: case study of the Laboreaux wastewater treatment plant.

    Science.gov (United States)

    Rosa, A P; Conesa, J A; Fullana, A; Melo, G C B; Borges, J M; Chernicharo, C A L

    2016-01-01

    This work assessed the energy potential and alternative usages of biogas and sludge generated in upflow anaerobic sludge blanket reactors at the Laboreaux sewage treatment plant (STP), Brazil. Two scenarios were considered: (i) priority use of biogas for the thermal drying of dehydrated sludge and the use of the excess biogas for electricity generation in an ICE (internal combustion engine); and (ii) priority use of biogas for electricity generation and the use of the heat of the engine exhaust gases for the thermal drying of the sludge. Scenario 1 showed that the electricity generated is able to supply 22.2% of the STP power demand, but the thermal drying process enables a greater reduction or even elimination of the final volume of sludge to be disposed. In Scenario 2, the electricity generated is able to supply 57.6% of the STP power demand; however, the heat in the exhaust gases is not enough to dry the total amount of dehydrated sludge.

  8. Effect of different sulfides on cadmium distribution during sludge combustion based on experimental and thermodynamic calculation approaches.

    Science.gov (United States)

    Liu, Jing-Yong; Fu, Jie-Wen; Sun, Shui-Yu; Ning, Xun-An; Wang, Yu-Jie; Chen, Tao; Luo, Guang-Qian; Xie, Wu-Ming; Yang, Zuo-Yi; Zhuo, Zhong-Xu

    2015-01-01

    The effects of sulfur compounds on the migration of a semi-volatile heavy metal (cadmium) during sludge incineration were investigated with two methods, i.e., experiments in a tubular furnace reactor and thermodynamic equilibrium calculations. The representative typical sludge with and without the addition of sulfur compounds was incinerated at 850 °C. The partitioning of Cd among the solid phase (bottom ash) and gas phase (fly ash and flue gas) was quantified. The results indicate that sulfur compounds in the elemental form and a reduced state could stabilize Cd in the form of CdS, aluminosilicate minerals, and polymetallic sulfides, whereas sulfur in the oxidized forms slightly increases Cd volatilization during incineration. For Cd solidification points, the inhibition effect on the volatilization of Cd is as follows: S > Na2SO4 > Na2S. Chemical equilibrium calculations indicate that sulfur binds with Cd and alters Cd speciation at low temperatures (sludge incineration.

  9. Effect of excess air on second-generation PFB combustion plant performance and economics

    International Nuclear Information System (INIS)

    Robertson, A.; Garland, R.; Newby, R.; Rehmat, A.; Rubow, L.; Bonk, D.

    1990-01-01

    This paper presents a conceptual design of a 1.4-MPa (14-atm) coal-fired second-generation pressurized fluidized bed (PFB) combustion plant and identifies the performance and economic changes that result as the excess air and thus gas turbine-to-steam turbine power ratio, is changed. The performance of these plants, another second- generation PFB combustion plant, and a conventional pulverized-coal (PC)-fired plant with wet limestone flue gas desulfurization is compared. Depending upon the conditions selected, the PFB combustion plant can achieve a 45 percent efficiency (based on the higher heating value of the coal used as fuel) and a cost of electricity at least 20 percent lower than that of the conventional PC-fired plant

  10. Thermal fragmentation and deactivation of combustion-generated soot particles

    KAUST Repository

    Raj, Abhijeet

    2014-09-01

    The effect of thermal treatment on diesel soot and on a commercial soot in an inert environment under isothermal conditions at intermediate temperatures (400-900°C) is studied. Two important phenomena are observed in both the soot samples: soot fragmentation leading to its mass loss, and loss of soot reactivity towards O2. Several experimental techniques such as high resolution transmission electron microscopy, electron energy loss spectroscopy, thermo-gravimetric analysis with mass spectrometry, elemental analysis, Fourier transform infrared spectroscopy and X-ray diffraction have been used to identify the changes in structures, functional groups such as oxygenates and aliphatics, σ and π bonding, O/C and H/C ratios, and crystallite parameters of soot particles, introduced by heat. A decrease in the size of primary particles and an increase in the average polycyclic aromatic hydrocarbon (PAH) size was observed in soots after thermal treatment. The activation energies of soot oxidation for thermally treated soot samples were found to be higher than those for the untreated ones at most conversion levels. The cyclic or acyclic aliphatics with sp3 hybridization were present in significant amounts in all the soot samples, but their concentration decreased with thermal treatment. Interestingly, the H/C and the O/C ratios of soot particles increased after thermal treatment, and thus, they do not support the decrease in soot reactivity. The increase in the concentration of oxygenates on soot surface indicate that their desorption from soot surface in the form of CO, CO2 and other oxygenated compounds may not be significant at the temperatures (400-900°C) studied in this work. © 2014 The Combustion Institute.

  11. Technical and economic assessment of process of treatment of coated bituminous sludge by combustion/vitrification (report PNGMDR 2013-2015)

    International Nuclear Information System (INIS)

    2015-01-01

    This note reports the assessment of a processing by combustion/vitrification of about 60.000 parcels of coated bituminous sludge belonging to intermediate-level long-lived and low-level long-lived category, and warehoused on the Marcoule CEA site. This assessment identifies the front-end cost of an exploratory R and D which would be required to undo technological locks, the cost of design, realisation and exploitation of the associated installation, and the negative features dues to the lack of technological maturity and to the management of environmental risks and impacts in comparison with the reference industrial solution (geological storage). As a conclusion, the authors state that the process is still not technically feasible

  12. Co-firing a pressurized fluidized-bed combustion system with coal and refuse derived fuels and/or sludges. Task 16

    Energy Technology Data Exchange (ETDEWEB)

    DeLallo, M.; Zaharchuk, R.

    1994-01-01

    The co-firing of waste materials with coal in utility scale power plants has emerged as an effective approach to produce energy and manage municipal waste. Leading this approach, the atmospheric fluidized-bed combustor (AFBC) has demonstrated its commercial acceptance in the utility market as a reliable source of power burning a variety of waste and alternative fuels. The fluidized bed, with its stability of combustion, reduces the amount of thermochemical transients and provides for easier process control. The application of pressurized fluidized-bed combustor (PFBC) technology, although relatively new, can provide significant enhancements to the efficient production of electricity while maintaining the waste management benefits of AFBC. A study was undertaken to investigate the technical and economic feasibility of co-firing a PFBC with coal and municipal and industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in central power station and distributed locations. Wastes considered for co-firing include municipal solid waste (MSW), tire-derived fuel (TDF), sewage sludge, and industrial de-inking sludge. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. This paper describes the results of this investigation, presents conclusions on the key issues, and provides recommendations for further evaluation.

  13. Sewage sludge as additive to reduce the initial fireside corrosion caused by combustion of shredder residues in a waste-fired BFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Jonsson, T.; Pettersson, J.; Johansson, L.G.; Svensson, J.E. [Chalmers Univ. of Technology, Goeteborg (Sweden). Environmental Inorganic Chemistry; Davidsson, K. [SP Technical Research Institute of Sweden, Boraas (Sweden)

    2010-07-01

    Corrosion/deposition field tests have been carried out in a commercial waste-fired BFB boiler using air-cooled probes. The influence of 20% shredder light fraction (SLF), from recovery of metal scrap material, mixed with waste was studied at different material temperatures (280-420 C). In addition, 3% sewage sludge was added to the 20% SLF/waste mixture. The initial deposit and corrosion products were compared to when the normal waste (municipal solid waste and industrial wastes) fuel was used. After 24 hours exposure, the deposits were analyzed as for elemental composition while the corrosion products were characterised by ESEM/EDX and XRD. The results show that combustion of 20% SLF increased the amount of deposition, which in addition contains a larger fraction chlorine. This causes a higher initial corrosion rate. Adding 3% sewage sludge removes the effect of the SLF and deposits and corrosion products were comparable with the ones formed during the reference exposure. The results indicate that the initial fireside corrosion is chlorine induced and no signs of low-melting heavy metals salts were observed in the corrosion products. (orig.)

  14. NOx reduction using amine reclaimer wastes (ARW) generated in post combustion CO2 capture

    DEFF Research Database (Denmark)

    Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

    2012-01-01

    Amine reclaimer wastes (ARW) generated in CO2 capture processes demand suitable disposal means. Such wastes contain remaining amine, NH3 and other degradation compounds. This study investigated the potential of using ARW as a NOx reducing agent, under laboratory conditions in a flow reactor. A si...... to combustion processes, including cement industry kilns....

  15. Biomass Gasification for Power Generation Internal Combustion Engines. Process Efficiency

    International Nuclear Information System (INIS)

    Lesme-Jaén, René; Garcia-Faure, Luis; Oliva-Ruiz, Luis; Pajarín-Rodríguez, Juan; Revilla-Suarez, Dennis

    2016-01-01

    Biomass is a renewable energy sources worldwide greater prospects for its potential and its lower environmental impact compared to fossil fuels. By different processes and energy conversion technologies is possible to obtain solid, liquid and gaseous fuels from any biomass.In this paper the evaluation of thermal and overall efficiency of the gasification of Integral Forestry Company Santiago de Cuba is presented, designed to electricity generation from waste forest industry. The gasifier is a downdraft reactor, COMBO-80 model of Indian manufacturing and motor (diesel) model Leyland modified to work with producer gas. The evaluation was conducted at different loads (electric power generated) of the motor from experimental measurements of flow and composition of gas supplied to the engine. The results show that the motor operates with a thermal efficiency in the range of 20-32% with an overall efficiency between 12-25 %. (author)

  16. Comparison of combustion and pyrolysis for energy generation in a sugarcane mill

    International Nuclear Information System (INIS)

    Nsaful, F.; Görgens, J.F.; Knoetze, J.H.

    2013-01-01

    Highlights: • Biomass to energy processes for sugarmills via combustion and pyrolysis are modelled. • Models compared based on technical and economic performance for two mill efficiencies. • Combustion more suited for sugar mill energy supply. • Pyrolysis based models have higher overall process efficiencies. • Pyrolysis contributes more towards environmental mitigation but is less profitable. - Abstract: The study focusses on the comparison of biomass to energy conversion process (BMECP) models to convert sugar mill biomass (bagasse) into energy products via combustion and pyrolysis as thermochemical pathways. Bagasse was converted to steam and electricity via combustion using 40 bar, 63 bar and 82 bar Condensing Extraction Steam Turbines (CEST) systems and a 30 bar back pressure steam turbine (BPST) system. Two BMECPs, namely partial fast pyrolysis and pure fast pyrolysis systems, were modeled for the pyrolysis pathway. In the Pure Fast Pyrolysis BMECP all the input bagasse stream was converted to pyrolysis products, with subsequent combustion of some of these products to generate steam and electricity for sugar mill operations. In the partial fast pyrolysis BMECP, a fraction of the bagasse is combusted directly to supply steam and electricity to the sugar mill, while the remaining fraction is pyrolyzed to generate pyrolysis products. All process models were simulated in AspenPlus® and were assessed on their ability to supply the energy requirement of to two sugar mill scenarios: More efficient mill and less efficient mill. The economic viability of BMECPs was determined using Aspen Process Economic Analyzer. Both combustion based and pyrolysis based BMECPs were capable of meeting the energy requirement of the sugar mill, although the pyrolysis based BMECP had limited steam and electricity production rates due to the accumulation of energy in pyrolysis products. High energy valued pyrolysis products resulted in higher overall process efficiencies of 85

  17. Gasdynamic modeling and parametric study of mesoscale internal combustion swing engine/generator systems

    Science.gov (United States)

    Gu, Yongxian

    The demand of portable power generation systems for both domestic and military applications has driven the advances of mesoscale internal combustion engine systems. This dissertation was devoted to the gasdynamic modeling and parametric study of the mesoscale internal combustion swing engine/generator systems. First, the system-level thermodynamic modeling for the swing engine/generator systems has been developed. The system performance as well as the potentials of both two- and four-stroke swing engine systems has been investigated based on this model. Then through parameterc studies, the parameters that have significant impacts on the system performance have been identified, among which, the burn time and spark advance time are the critical factors related to combustion process. It is found that the shorter burn time leads to higher system efficiency and power output and the optimal spark advance time is about half of the burn time. Secondly, the turbulent combustion modeling based on levelset method (G-equation) has been implemented into the commercial software FLUENT. Thereafter, the turbulent flame propagation in a generic mesoscale combustion chamber and realistic swing engine chambers has been studied. It is found that, in mesoscale combustion engines, the burn time is dominated by the mean turbulent kinetic energy in the chamber. It is also shown that in a generic mesoscale combustion chamber, the burn time depends on the longest distance between the initial ignition kernel to its walls and by changing the ignition and injection locations, the burn time can be reduced by a factor of two. Furthermore, the studies of turbulent flame propagation in real swing engine chambers show that the combustion can be enhanced through in-chamber turbulence augmentation and with higher engine frequency, the burn time is shorter, which indicates that the in-chamber turbulence can be induced by the motion of moving components as well as the intake gas jet flow. The burn time

  18. A new process to improve short-chain fatty acids and bio-methane generation from waste activated sludge.

    Science.gov (United States)

    Dong, Bin; Gao, Peng; Zhang, Dong; Chen, Yinguang; Dai, Lingling; Dai, Xiaohu

    2016-05-01

    As an important intermediate product, short-chain fatty acids (SCFAs) can be generated after hydrolysis and acidification from waste activated sludge, and then can be transformed to methane during anaerobic digestion process. In order to obtain more SCFA and methane, most studies in literatures were centered on enhancing the hydrolysis of sludge anaerobic digestion which was proved as un-efficient. Though the alkaline pretreatment in our previous study increased both the hydrolysis and acidification processes, it had a vast chemical cost which was considered uneconomical. In this paper, a low energy consumption pretreatment method, i.e. enhanced the whole three stages of the anaerobic fermentation processes at the same time, was reported, by which hydrolysis and acidification were both enhanced, and the SCFA and methane generation can be significantly improved with a small quantity of chemical input. Firstly, the effect of different pretreated temperatures and pretreatment time on sludge hydrolyzation was compared. It was found that sludge pretreated at 100°C for 60min can achieve the maximal hydrolyzation. Further, effects of different initial pHs on acidification of the thermal pretreated sludge were investigated and the highest SCFA was observed at initial pH9.0 with fermentation time of 6d, the production of which was 348.63mg COD/gVSS (6.8 times higher than the blank test) and the acetic acid was dominant acid. Then, the mechanisms for this new pretreatment significantly improving SCFA production were discussed. Finally, the effect of this low energy consumption pretreatment on methane generation was investigated. Copyright © 2015. Published by Elsevier B.V.

  19. Corrosivity of cement pastes with addition of sludge generated in water treatment plant

    International Nuclear Information System (INIS)

    Rodrigues, R.A.; Martins, B.E.D.B.S.; Couto, V.M.P.; Carvalho, L.J.; Almeida, V.C.

    2011-01-01

    The amount of sludge produced in a water treatment plant (WTP) is an important economic factor in the context of waste treatment. The present article has the objective of study the corrosion of cement pastes produced with blended sludge. Aqueous extracts were produced from the milling of masses containing 5%, 10% and 30% of sludge in relation to cement after 28 days of healing. These extracts were used for polarization assays in order to determine the corrosiveness of the folders when in contact with the used fittings. Moreover, other chemical analysis tests were carried out for sludge characterization: X-ray fluorescence and X-ray diffraction. The obtained results point to the possibility of use of the studied cement masses in the development of construction materials promoting the economic reuse of WTP sludge before discarded in landfills. (author)

  20. Anaerobic degradation of amino acids generated from the hydrolysis of sewage sludge.

    Science.gov (United States)

    Park, Junghoon; Park, Seyong; Kim, Moonil

    2014-01-01

    The anaerobic degradation of each amino acid that could be generated through the hydrolysis of sewage sludge was evaluated. Stickland reaction as an intermediate reaction between two kinds of amino acids was restricted in order to evaluate each amino acid. Changes in the chemical oxygen demand (COD), T-N, NH4(+)-N, biogas, and CH4 were analysed for the anaerobic digestion process. The initial nitrogen concentration of all amino acids is adjusted as 1000 mg/L. The degradation rate of the amino acids was determined based on the ammonia form of nitrogen, which is generated by the deamination of amino acids. Among all amino acids, such as alpha-alanine, beta-alanine, lysine, arginine, glycine, histidine, cysteine, methionine, and leucine, deamination rates of cysteine, leucine, and methionine were just 61.55%, 54.59%, and 46.61%, respectively, and they had low removal rates of organic matter and showed very low methane production rates of 13.55, 71.04, and 80.77 mL CH4/g CODin, respectively. Especially for cysteine, the methane content was maintained at approximately 7% during the experiment. If wastewater contains high levels of cysteine, leucine, and methionine and Stickland reaction is not prepared, these amino acids may reduce the efficiency of the anaerobic digestion.

  1. Co-combustion of waste materials using fluidized bed technology

    Energy Technology Data Exchange (ETDEWEB)

    M. Lopes; I. Gulyurtlu; P. Abelha; T. Crujeira; D. Boavida; I. Cabrita [INETI-DEECA, Lisbon (Portugal)

    2004-07-01

    There is growing interest in using renewable fuels in order to sustain the CO{sub 2} accumulation. Several waste materials can be used as coal substitutes as long as they contain significant combustible matter, as for example MSW and sewage sludge. Besides the outcome of the energetic valorization of such materials, combustion must be regarded as a pre-treatment process, contributing to the safe management of wastes. Landfilling is an expensive management option and requires a previous destruction of the organic matter present in residues, since its degradation generates greenhouse gases and produces acidic organic leachates. Fluidized bed combustion is a promising technology for the use of mixtures of coal and combustible wastes. This paper presents INETI's experience in the co-combustion of coal with this kind of residues performed in a pilot fluidized bed. Both the RDF (from MSW and sewage sludge) and sewage sludge combustion problems were addressed, relating the gaseous emissions, the behaviour of metals and the leachability of ashes and a comparison was made between co-combustion and mono-combustion in order to verify the influence of the utilization of coal. 9 refs., 1 fig., 3 tabs.

  2. Analyses of Injection-Coupled Combustion Instability from J-2X Gas Generator Development

    Science.gov (United States)

    Hulka, James R.; Kenny, R. Jeremy; Protz, Chris; Casiano, Matthew

    2011-01-01

    During development of the gas generator for the liquid oxygen/liquid hydrogen propellant J-2X rocket engine, combustion instabilities were observed near the frequency of the first longitudinal acoustic mode of the hot gas combustion chamber duct. These instabilities were similar to intermediate-frequency or buzz-type instabilities as described in historical programs, except for several aspects: 1) the frequencies were low, in the realm of chug; 2) at times the instability oscillation amplitudes were quite large, with peak-to-peak amplitudes exceeding 50% of the mean chamber pressure along with the appearance of harmonics; 3) the chamber excitation was related to but not exactly at the first longitudinal combustion chamber acoustic mode; and 4) the injector provided mass flow rate oscillations induced by capacitance and inertance effects in the injector rather than by organ pipe resonances of the coaxial oxidizer posts. This type of combustion instability is referred to as "injection coupling" because one critical driving source of the instability is mass flow rate oscillations from the injector. However, the type of injection coupling observed here is different than observed in previous instances of buzz instability with coaxial injectors, because of the lower frequencies and lack of influence from the oxidizer post organ pipe resonances. Test data and preliminary analyses of the initial combustion instabilities were presented in several papers at the 5th Liquid Propulsion Subcommittee meeting. Since that time, additional hot-fire tests with several new hardware configurations have been conducted, and additional analyses have been completed. The analytical models described in previous papers have been updated to include the influences of new geometrical configurations, including a different oxidizer injector manifold configuration and a branch pipe in the hot gas duct that supplies gaseous helium during the start transient to pre-spin the turbine. In addition, the

  3. Briquettes production for use as power source for combustion using charcoal thin waste and sanitary sewage sludge.

    Science.gov (United States)

    de Oliveira, Ricardo Sonsim; Palácio, Soraya Moreno; da Silva, Edson Antonio; Mariani, Filipe Quadros; Reinehr, Thiago Olinek

    2017-04-01

    This study evaluated the feasibility of production of briquettes using fine charcoal, sewage sludge, and mixtures thereof for use in energy production. The briquettes of 7-8 cm diameter and 20 cm length were produced in the conical press extruder type, mixing sewage sludge to charcoal fines in different ratios: 0:100, 25:75, 50:50, 75:25, and 100:0, with the addition of a binder (glue flour) in a ratio of 8 mass% prepared for briquetting. After air drying (temperatures between 24 and 30°C) for 48 h, the mechanical, thermal, and morphological characterizations were performed. The morphological properties of the briquettes were evaluated by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The briquettes produced had mechanical strength, with values between 210 and 420 kgf, and densities between 0.75 and 0.91 g cm -3 . The calorific value of briquettes was in the range from 13.21 to 23.10 MJ kg -1 , in which there was an increase with the increase of concentration of charcoal fines in the mixture. Thermogravimetric analysis showed mass losses that occurred in the temperature range between 150 and 740 °C. The results of the mechanical and thermal properties showed the feasibility of using fine charcoal briquettes from sewage sludge as well as mixtures thereof, for the production of energy. The fine charcoal briquette was the one with the highest calorific value, but not showed the highest resistance to mechanical shock.

  4. Towards numerical simulation of turbulent hydrogen combustion based on flamelet generated manifolds in OpenFOAM

    Science.gov (United States)

    Fancello, A.; Bastiaans, R. J. M.; de Goey, L. P. H.

    2013-10-01

    This work proposes an application of the Flamelet-Generated Manifolds (FGM) technique in the OpenFOAM environment. FGM is a chemical reduced method for combustion modeling. This technique treats the combustion process as the solution of a small amount of controlling variables. Regarding laminar simulation, a progress variable and enthalpy evolution can describe satisfactorily the problem. From a turbulent point of view, FGM can be applied to LES and RANS simulations, where the subgrid chemical terms are described with a β - PDF approach. These approaches apply satisfactorily in relatively simple gases, nevertheless for hydrogen are not more valid, due to preferential diffusion effects and instability of the flame structure. The overall aim of this research is to find technical solution for hydrogen gas turbines design in the next generation of Integrated Gasification Combined Cycle (IGCC) plants.

  5. Mineralogy and metals speciation in Mo rich mineral sludges generated at a metal recycling plant.

    Science.gov (United States)

    Vemic, M; Bordas, F; Guibaud, G; Joussein, E; Labanowski, J; Lens, P N L; van Hullebusch, E D

    2015-04-01

    In France, more than 250 million metric tons of sludges need to be treated each year. These sludges are either dumped on the landfills or reused as secondary resources in order to preserve natural resources. A large portions of these sludges are mineral sludges, originating from metal recycling plants. In order to estimate their metal recovery potential, these mineral sludges were characterized. Four types of mineral sludge samples were collected from a metal recycling plant (3 from the recycling plant storage areas (bulk storage, barrel storage and storage shed) and 1 from the collection basin). The sludges were characterized, wherein the Mo, Ni, Cr, Co, Zn and W content and speciation were quantified. The samples had pH values between 5.9 and 10.3 with organic matter contents varying between 6.3% (storage shed) and 29.5% (bulk storage) (loss on ignition at 500 °C). Based on their leaching properties, the four mineral sludge samples (in the case of Mo) and the bulk storage sludge (in the case of Ni and Zn) were classified as potentially hazardous regarding the EN 12457-1 and EN 12457-2 method. Mineralogical results reveal that both bulk storage and the storage shed give the highest contributions to the metal content of the collection basin sample. Sequential extraction of the collection basin samples indicated that Mo is bound to the oxidizable and residual fraction, while Ni, Cr and Co were bound to the residual fraction, and Zn to the soluble acid fraction, respectively. W tends to be equally distributed among all extracted fractions. A strong correlation existed between Mo and Co, as well as between Ni, Zn and Cr, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Development of Kinetic Mechanisms for Next-Generation Fuels and CFD Simulation of Advanced Combustion Engines

    Energy Technology Data Exchange (ETDEWEB)

    Pitz, William J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McNenly, Matt J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Whitesides, Russell [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mehl, Marco [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Killingsworth, Nick J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Westbrook, Charles K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-12-17

    Predictive chemical kinetic models are needed to represent next-generation fuel components and their mixtures with conventional gasoline and diesel fuels. These kinetic models will allow the prediction of the effect of alternative fuel blends in CFD simulations of advanced spark-ignition and compression-ignition engines. Enabled by kinetic models, CFD simulations can be used to optimize fuel formulations for advanced combustion engines so that maximum engine efficiency, fossil fuel displacement goals, and low pollutant emission goals can be achieved.

  7. Energy Generation from Horse Husbandry Residues by Anaerobic Digestion, Combustion, and an Integrated Approach

    Directory of Open Access Journals (Sweden)

    Meike Nitsche

    2017-02-01

    Full Text Available Horse-related activities often occur close to urban areas, where acreage for horse manure disposal is scarce, and subsequently alternative recovery options are necessary. Anaerobic digestion, direct combustion, and the integrated generation of solid fuel and biogas from biomass (IFBB process are potential techniques focusing on energy provision. In this study, samples of horse faeces were analysed for chemical composition as pure feedstock and in mixture with straw or wood shavings, as well as for energy yield by biogas production or from combustion of solid fuel. It was observed that chemical properties of faeces, in a mixture with wood shavings, were promising for direct combustion, but achieved low methane yields. The methane yield of pure faeces and the straw mixture was 222.33 ± 13.60 and 233.01 ± 31.32 lN·kg-1 volatile solids (VSadded, respectively. The IFBB process divided the biomass into a press cake with reduced mineral concentration and a press fluid. Methane yields of press fluids were low (108.2 lN·kg-1 VSadded, on average. The chemical composition of the press cake allowed for combustion and led to a higher gross energy potential than anaerobic digestion (two-fold higher for pure manure and the mixture with straw, and five-fold higher for the mixture with shavings. Consequently, the gross energy potential of IFBB is higher compared to anaerobic digestion, however it should be noted that local conditions might favour the implementation of anaerobic digestion.

  8. Gaseous products and smoke generation on combustion of the insulation materials of nuclear cables

    International Nuclear Information System (INIS)

    Noguchi, Isamu; Takami, Hiroshi; Ueyama, Michio; Fujimura, Shun-ichi.

    1976-01-01

    Serious requirements have been introduced to the cables used for nuclear power plants on their flame retardation in the IEEE Standard 383-1974. The movements that the users prescribe the quantity of corrosive gas generated from cables are also observed. This report describes on the measured results of the gaseous products generated by burning polyethylene, polyvinyl-chloride (PVC) and their flame-resistant products, and a part of the covering materials of the cables for nuclear power plants (flame-resistant, crosslinking polyethylene, flame-resistant, low hydrochloric acid PVC, flame-resistant jute) in the infra-red rapid heating combustion test facility designed by the Furukawa Electric Co. Ltd. In addition, the report introduces the test method for the smoke generation evaluation of polymers and a part of the measured results. The gaseous products of combustion were collected and determined quantitatively by gas chromatographic method. Since smoke generation is affected greatly by the kinds, shape, atmosphere, temperature, ignition procedure and others of burnt matters, the establishment of the evaluation test method is difficult, and a number of methods have been proposed. As the measured results showed, it is clear that smoke generation increases with the increase of flame resistant reagent addition. The smoke generation of PVC was of course great in quantity because it contains considerable amount of chlorine for its molecular structure. Flame-resistant polyethylene generates smoke much more than polyethylene without flame-resisting treatment because of its flame resistivity, but less than that of PVC. (Wakatsuki, Y.)

  9. Design and Operation of the Synthesis Gas Generator System for Reformed Propane and Glycerin Combustion

    Science.gov (United States)

    Pickett, Derek Kyle

    Due to an increased interest in sustainable energy, biodiesel has become much more widely used in the last several years. Glycerin, one major waste component in biodiesel production, can be converted into a hydrogen rich synthesis gas to be used in an engine generator to recover energy from the biodiesel production process. This thesis contains information detailing the production, testing, and analysis of a unique synthesis generator rig at the University of Kansas. Chapter 2 gives a complete background of all major components, as well as how they are operated. In addition to component descriptions, methods for operating the system on pure propane, reformed propane, reformed glycerin along with the methodology of data acquisition is described. This chapter will serve as a complete operating manual for future students to continue research on the project. Chapter 3 details the literature review that was completed to better understand fuel reforming of propane and glycerin. This chapter also describes the numerical model produced to estimate the species produced during reformation activities. The model was applied to propane reformation in a proof of concept and calibration test before moving to glycerin reformation and its subsequent combustion. Chapter 4 first describes the efforts to apply the numerical model to glycerin using the calibration tools from propane reformation. It then discusses catalytic material preparation and glycerin reformation tests. Gas chromatography analysis of the reformer effluent was completed to compare to theoretical values from the numerical model. Finally, combustion of reformed glycerin was completed for power generation. Tests were completed to compare emissions from syngas combustion and propane combustion.

  10. WMU Power Generation Study Task 2.0 Corn Cob Co-Combustion Study: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Folkedahl, Bruce [Folkedahl Consulting, Inc., Willmar, MN (United States)

    2009-12-01

    Much attention has been focused on renewable energy use in large-scale utilities and very small scale distributed energy systems. However, there is little information available regarding renewable energy options for midscale municipal utilities. The Willmar Municipal Utilities Corn Cob-Coal Co-Combustion Project was initiated to investigate opportunities available for small to midscale municipal utilities to "go green". The overall goal of the Project was to understand the current renewable energy research and energy efficiency projects that are or have been implemented at both larger and smaller scale and determine the applicability to midscale municipal utilities. More specific objectives for Task 2.0 of this project were to determine the technical feasibility of co-combusting com cobs with coal in the existing WMU boiler, and to identify any regulatory issues that might need to be addressed if WMU were to obtain a significant portion of its heat from such co-combustion. This report addresses the issues as laid out in the study proposal. The study investigated the feasibility of and demonstrated the technical effectiveness of co-combusting corn cobs with coal in the Willmar Municipal Utilities stoker boiler steam generation power plant. The results of the WMU Co-Combustion Project will serve as a model for other midscale utilities who wish to use corn cobs to generate renewable electrical energy. As a result of the Co-Combustion Project, the WMU plans to upgrade their stoker boiler to accept whole corn cobs as well as other types of biomass, while still allowing the fuel delivery system to use 100% coal as needed. Benefits of co-combustion will include: energy security, reduced Hg and CO2 air emissions, improved ash chemistry, potential future carbon credit sales, an immediate positive effect on the local economy, and positive attention focused on the WMU and the City of Willmar. The first step in the study was to complete a feasibility analysis. The

  11. Engineering design and exergy analyses for combustion gas turbine based power generation system

    International Nuclear Information System (INIS)

    Sue, D.-C.; Chuang, C.-C.

    2004-01-01

    This paper presents the engineering design and theoretical exergetic analyses of the plant for combustion gas turbine based power generation systems. Exergy analysis is performed based on the first and second laws of thermodynamics for power generation systems. The results show the exergy analyses for a steam cycle system predict the plant efficiency more precisely. The plant efficiency for partial load operation is lower than full load operation. Increasing the pinch points will decrease the combined cycle plant efficiency. The engineering design is based on inlet air-cooling and natural gas preheating for increasing the net power output and efficiency. To evaluate the energy utilization, one combined cycle unit and one cogeneration system, consisting of gas turbine generators, heat recovery steam generators, one steam turbine generator with steam extracted for process have been analyzed. The analytical results are used for engineering design and component selection

  12. Investigation of co-combustion characteristics of sewage sludge and coffee grounds mixtures using thermogravimetric analysis coupled to artificial neural networks modeling.

    Science.gov (United States)

    Chen, Jiacong; Liu, Jingyong; He, Yao; Huang, Limao; Sun, Shuiyu; Sun, Jian; Chang, KenLin; Kuo, Jiahong; Huang, Shaosong; Ning, Xunan

    2017-02-01

    Artificial neural network (ANN) modeling was applied to thermal data obtained by non-isothermal thermogravimetric analysis (TGA) from room temperature to 1000°C at three different heating rates in air to predict the TG curves of sewage sludge (SS) and coffee grounds (CG) mixtures. A good agreement between experimental and predicted data verified the accuracy of the ANN approach. The results of co-combustion showed that there were interactions between SS and CG, and the impacts were mostly positive. With the addition of CG, the mass loss rate and the reactivity of SS were increased while charring was reduced. Measured activation energies (E a ) determined by the Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) methods deviated by <5%. The average value of E a (166.8kJ/mol by KAS and 168.8kJ/mol by OFW, respectively) was the lowest when the fraction of CG in the mixture was 40%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Prediction of Non-Equilibrium Kinetics of Fuel-Rich Kerosene/LOX Combustion in Gas Generator

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jung Min; Lee, Chang Jin [Konkuk University, Seoul (Korea, Republic of)

    2007-08-15

    Gas generator is the device to produce high enthalpy gases needed to drive turbo-pump system in liquid rocket engine. And, the combustion temperature in gas generator should be controlled below around 1,000K to avoid any possible thermal damages to turbine blade by using either fuel rich combustion or oxidizer rich combustion. Thus, nonequilibrium chemical reaction dominates in fuel-rich combustion of gas generator. Meanwhile, kerosene is a compounded fuel with various types of hydrocarbon elements and difficult to model the chemical kinetics. This study focuses on the prediction of the non-equilibrium reaction of fuel rich kerosene/LOX combustion with detailed kinetics developed by Dagaut using PSR (Perfectly Stirred Reactor) assumption. In Dagaut's surrogate model for kerosene, chemical kinetics of kerosene consists of 1,592 reaction steps with 207 chemical species. Also, droplet evaporation time is taken into account in the PSR calculation by changing the residence time of droplet in the gas generator. Frenklach's soot model was implemented along with detailed kinetics to calculate the gas properties of fuel rich combustion efflux. The results could provide very reliable and accurate numbers in the prediction of combustion gas temperature,species fraction and material properties.

  14. Prediction of Non-Equilibrium Kinetics of Fuel-Rich Kerosene/LOX Combustion in Gas Generator

    International Nuclear Information System (INIS)

    Yu, Jung Min; Lee, Chang Jin

    2007-01-01

    Gas generator is the device to produce high enthalpy gases needed to drive turbo-pump system in liquid rocket engine. And, the combustion temperature in gas generator should be controlled below around 1,000K to avoid any possible thermal damages to turbine blade by using either fuel rich combustion or oxidizer rich combustion. Thus, nonequilibrium chemical reaction dominates in fuel-rich combustion of gas generator. Meanwhile, kerosene is a compounded fuel with various types of hydrocarbon elements and difficult to model the chemical kinetics. This study focuses on the prediction of the non-equilibrium reaction of fuel rich kerosene/LOX combustion with detailed kinetics developed by Dagaut using PSR (Perfectly Stirred Reactor) assumption. In Dagaut's surrogate model for kerosene, chemical kinetics of kerosene consists of 1,592 reaction steps with 207 chemical species. Also, droplet evaporation time is taken into account in the PSR calculation by changing the residence time of droplet in the gas generator. Frenklach's soot model was implemented along with detailed kinetics to calculate the gas properties of fuel rich combustion efflux. The results could provide very reliable and accurate numbers in the prediction of combustion gas temperature,species fraction and material properties

  15. Bio filtration of smell emission generated by biological sludge dewatering; Biofiltrazione di emissioni maleodoranti generate dalla disidratazione di fanghi biologici

    Energy Technology Data Exchange (ETDEWEB)

    Collivignarelli, C. [Brescia Univ. (Italy). Dipt. di Ingegneria Civile. Facolta' di Ingegneria; Riganti, V. [Pavia Univ. (Italy). Dipt. di Chimica Generale; Berri, A. [Fondazione S. Maugeri, Pavia (Italy); Colombi, A. [Milan Univ. (Italy). Clinica del Lavoro L. Devoto; Conti, F. [Pavia Univ. (Italy). Dipt. di Ingegneria Idraulica e Ambientale; Decarro, C. [Pavia Univ. (Italy). Ist. di Farmacologia; Del Frate, G. [Pavia Univ. (Italy). Dipt. di Ecologia del Territorio e degli Ambienti Terrestri. Ist. di Micologia Medica; Gerla, R. [Ecodeco SpA, Loc. Cassinazza, Giussago, PV (Italy)

    1999-06-01

    This work presents the results of a pilot scale experience about smelling air treatment by means of bio filtration. The odor emission is generated in a dewatering process of the sludge derived from an industrial wastewater biological treatment. The study was carried out by chemical, chemical-physical, microbiological and organoleptic (olfactometric) analysis. Hydrogen sulfide is the main pollutant removed by this treatment; for this parameter a mass balance was developed to validate the collected data. The result was also compared with the ones of a similar treatment experience carried out on a flue gas derived from a different source (pretreatment of liquid waste). This procedure confirmed the good treatmen capacity of the bio filtration process. [Italian] Quasta relazione illustra i risultati di una esperienza su scala pilota di trattamento mediante biofiltrazione di aria maleodorante. L'emissione odorosa e' generata dal trattamento di disidratazione dei fanghi prodotti da un processo di depurazione biologica dei reflui industriali. Lo studio e' stato condotto mediante l'esecuzione di analisi chimiche e chimico-fisiche, microbiologiche e organolettiche (olfattometriche). Il principale inquinante abbattuto dal trattamento e' il solfuro di idrogeno; su questo parametro e' stato impostato un bilancio di massa per la validazione degli ottimi risultati rilevati. I dati raccolti sono anche confrontati con gli esiti di un'analoga esperienza di trattamento effettuata su un refluo di origine diversa (esalazioni da pretrattamento di rifiuti liquidi) confermando la sostanziale capacita' di trattamento del sistema di biofiltrazione.

  16. Improving bioelectricity generation and COD removal of sewage sludge in microbial desalination cell.

    Science.gov (United States)

    Ebrahimi, Atieh; Yousefi Kebria, Daryoush; Darzi, Ghasem Najafpour

    2018-05-01

    Improving wastewater treatment process and water desalination are two important solutions for increasing the available supply of fresh water. Microbial desalination cells (MDCs) with common electrolytes display relatively low organic matter removal and high cost. In this study, sewage sludge was used as the substrate in the Microbial desalination cell (MDC) under three different initial salt concentrations (5, 20 and 35 g.L -1 ) and the maximum salt removal rates of 50.6%, 64% and 69.6% were obtained under batch condition, respectively. The MDC also produced the maximum power density of 47.1 W m -3 and the averaged chemical oxygen demand (COD) removal of 58.2 ± 0.89% when the initial COD was 6610 ± 83 mg L -1 . Employing treated sludge as catholyte enhanced COD removal and power density to 87.3% and 54.4 W m -3 , respectively, with counterbalancing pH variation in treated effluent. These promising results showed, for the first time, that the excess sewage sludge obtained from biological wastewater treatment plants could be successfully used as anolyte and catholyte in MDC, achieving organic matter biodegradation along with salt removal and energy production. In addition, using treated sludge as catholyte will improve the performance of MDC and introduce a more effective method for both sludge treatment and desalination.

  17. Automotive Thermoelectric Generator impact on the efficiency of a drive system with a combustion engine

    Directory of Open Access Journals (Sweden)

    Ziolkowski Andrzej

    2017-01-01

    Full Text Available Increasing the combustion engine drive systems efficiency is currently being achieved by structural changes in internal combustion engines and its equipment, which are geared towards limiting mechanical, thermal and outlet losses. For this reason, downsizing. In addition to these changes, all manner of exhaust gas energy recovery systems are being investigated and implemented, including turbocompound, turbogenerators and thermoelectric generators. The article presents the author’s idea of a thermoelectric generator system of automotive applications ATEG (Automotive Thermoelectric Generator and the study of the recovery of exhaust gas energy stream. The ATEG consists of a heat exchanger, thermoelectric modules and a cooling system. In this solution, 24 commercial thermoelectric modules based on Bi2Te3 (bismuth telluride were used. Measurements were made at two engine test sites on which SI and CI engines were installed. The exhaust gas parameters (temperature and mass flow rate, fuel consumption and operating parameters of the ATEG – the intensity and the voltage generated by the thermoelectric modules and the temperature on the walls of the heat exchanger – were all measured in the experiments. Based on the obtained results, the exhaust gas energy flow and the power of the ATEG were determined as well as its effect on the diesel engine drive system efficiency.

  18. A Second Generation Swirl-Venturi Lean Direct Injection Combustion Concept

    Science.gov (United States)

    Tacina, Kathleen M.; Chang, Clarence T.; He, Zhuohui Joe; Lee, Phil; Dam, Bidhan; Mongia, Hukam

    2014-01-01

    A low-NO (sub x) aircraft gas turbine engine combustion concept was developed and tested. The concept is a second generation swirl-venturi lean direct injection (SV-LDI) concept. LDI is a lean-burn combustion concept in which the fuel is injected directly into the flame zone. Three second generation SV-LDI configurations were developed. All three were based on the baseline 9-point SV-LDI configuration reported previously. These second generation configurations had better low power operability than the baseline 9-point configuration. Two of these second generation configurations were tested in a NASA Glenn Research Center flametube; these two configurations are called the at dome and 5-recess configurations. Results show that the 5-recess configuration generally had lower NO (sub x) emissions than the flat dome configuration. Correlation equations were developed for the flat dome configuration so that the landing-takeoff NO (sub x) emissions could be estimated. The flat dome landing-takeoff NO (sub x) is estimated to be 87-88 percent below the CAEP/6 standards, exceeding the ERA project goal of 75 percent reduction.

  19. Biomass Power Generation through Direct Integration of Updraft Gasifier and Stirling Engine Combustion System

    Directory of Open Access Journals (Sweden)

    Jai-Houng Leu

    2010-01-01

    Full Text Available Biomass is the largest renewable energy source in the world. Its importance grows gradually in the future energy market. Since most biomass sources are low in energy density and are widespread in space, small-scale biomass conversion system is therefore more competitive than a large stand-alone conversion plant. The current study proposes a small-scale solid biomass power system to explore the viability of direct coupling of an updraft fixed bed gasifier with a Stirling engine. The modified updraft fixed bed gasifier employs an embedded combustor inside the gasifier to fully combust the synthetic gas generated by the gasifier. The flue gas produced by the synthetic gas combustion inside the combustion tube is piped directly to the heater head of the Stirling engine. The engine will then extract and convert the heat contained in the flue gas into electricity automatically. Output depends on heat input. And, the heat input is proportional to the flow rate and temperature of the flue gas. The preliminary study of the proposed direct coupling of an updraft gasifier with a 25 kW Stirling engine demonstrates that full power output could be produced by the current system. It could be found from the current investigation that no auxiliary fuel is required to operate the current system smoothly. The proposed technology and units could be considered as a viable solid biomass power system.

  20. Evaluation of the influence of sludge generated coagulant contained in the ETA on ceramic bodies

    International Nuclear Information System (INIS)

    Martins, B.E.D.B.S.; Yokoyama, L.; Almeida, V.C.

    2014-01-01

    This study aims to evaluate the effects of the insertion of sludge produced in ETA, having both polyaluminum chloride as aluminum sulfate as a coagulant, clay, allowing to obtain an alternative to conventional ceramic material options. Compositions with different percentages of silt by the method of pressing shaping and burned at 900 ° C, 1100 ° C and 1200 ° C were prepared. The specimens were tested for water absorption and flexural stress. Were characterized by the techniques of X-ray fluorescence, X-ray diffraction and scanning electron microscopy results reveal that the nature of the sludge positively affects the quality of the ceramics prepared. (author)

  1. Use of biogas for cogeneration of heat and electricity for local application: performance evaluation of an engine power generator and a sludge thermal dryer.

    Science.gov (United States)

    Lobato, L C S; Chernicharo, C A L; Pujatti, F J P; Martins, O M; Melo, G C B; Recio, A A R

    2013-01-01

    A small unit of cogeneration of energy and heat was tested at the Centre for Research and Training on Sanitation UFMG/COPASA - CePTS, located at the Arrudas Sewage Treatment Plant, in Belo Horizonte, Minas Gerais, Brazil. The unit consisted of an engine power generator adapted to run on biogas, a thermal dryer prototype and other peripherals (compressor, biogas storage tank, air blower, etc.). The heat from engine power generator exhaust gases was directed towards the thermal dryer prototype to dry the sludge and disinfect it. The results showed that the experimental apparatus is self-sufficient in electricity, even producing a surplus, available for other uses. The tests of drying and disinfection of sludge lasted 7 h, leading to an increase in solids content from 4 to 8% (50% reduction in sludge volume). Although the drying of sludge was not possible (only thickening was achieved), the disinfection process proved very effective, enabling the complete inactivation of helminth eggs.

  2. Combustion noise

    Science.gov (United States)

    Strahle, W. C.

    1977-01-01

    A review of the subject of combustion generated noise is presented. Combustion noise is an important noise source in industrial furnaces and process heaters, turbopropulsion and gas turbine systems, flaring operations, Diesel engines, and rocket engines. The state-of-the-art in combustion noise importance, understanding, prediction and scaling is presented for these systems. The fundamentals and available theories of combustion noise are given. Controversies in the field are discussed and recommendations for future research are made.

  3. Accelerated Electromechanical Modeling of a Distributed Internal Combustion Engine Generator Unit

    Directory of Open Access Journals (Sweden)

    Serhiy V. Bozhko

    2012-07-01

    Full Text Available Distributed generation with a combustion engine prime mover is still widely used to supply electric power in a variety of applications. These applications range from backup power supply systems and combined wind-diesel generation to providing power in places where grid connection is either technically impractical or financially uneconomic. Modelling of such systems as a whole is extremely difficult due to the long-time load profiles needed and the computational difficulty of including small time-constant electrical dynamics with large time-constant mechanical dynamics. This paper presents the development of accelerated, reduced-order models of a distributed internal combustions engine generator unit. Overall these models are shown to achieve a massive improvement in the computational time required for long-time simulations while also achieving an extremely high level of dynamic accuracy. It is demonstrated how these models are derived, used and verified against benchmark models created using established techniques. Throughout the paper the modelling set as a whole, including multi level detail, is presented, detailed and finally summarised into a crucial tool for general system investigation and multiple target optimisation.

  4. A new process concept for highly efficient conversion of sewage sludge by combined fermentation and gasification and power generation in a hybrid system consisting of a SOFC and a gas turbine

    OpenAIRE

    Speidel, Michael; Kraaij, Gerard; Wörner, Antje

    2015-01-01

    Sewage sludge can be disposed of by fermentation, incineration or gasification. Conversion of the resulting biogas, combustion heat or gasification gas into electricity is often employed. Since sewage sludge cannot be fermented completely and due to the significant heat requirements for drying it in the incineration plant or before the gasifier, the electrical output in all cases is very low. Consequently, this work seeks to investigate a combination of fermentation and gasification in which ...

  5. The convergence of theory and experiment in direct combustion generated noise

    Science.gov (United States)

    Strahle, W. C.

    1975-01-01

    Current theories of combustion generated noise are reviewed with regard to their ability to predict the sound power output and spectral characteristics of noise generated by several flame types. New experimental information on open turbulent flames and on gas turbine combustor cans is presented. Available information on gas phase diffusion flames is reviewed. It is concluded that if some of the gross turbulence features of the flame are known and if the acoustical behavior of any flame enclosure is known, then scaling rules for behavior of the sound power output and spectral content may be quite accurately produced by theory. On the other hand, the theory is not sufficiently advanced to make absolute predictions; such predictions must await more detailed knowledge of turbulent flame structure.

  6. Start up system for hydrogen generator used with an internal combustion engine

    Science.gov (United States)

    Houseman, J.; Cerini, D. J. (Inventor)

    1977-01-01

    A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

  7. Hydrogen generation during melter feed preparation of Tank 42 sludge and salt washed loaded CST in the Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    Daniel, W.E.

    1999-01-01

    The main objective of these scoping tests was to measure the rate of hydrogen generation in a series of experiments designed to duplicate the expected SRAT and SME processing conditions in laboratory scale vessels. This document details the testing performed to determine the maximum hydrogen generation expected with a coupled flowsheet of sludge, loaded CST [crystalline silicotitanate], and frit

  8. A Study on the Combustion Characteristics of a Generator Engine Running on a Mixture of Syngas and Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung Hyun; Park, Cheol Woong [University of Science and Technology, Daejeon (Korea, Republic of); Lee, Sun Youp; Kim, Chang Gi [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

    2011-07-15

    Internal combustion engines running on syngas, which can be obtained from biomass or organic wastes, are expected to be one of the suitable alternatives for power generation, because they are environment-friendly and do not contribute to the depletion of fossil fuels. However, syngas has variable compositions and a lower heating value than pure natural gas, owing to which the combustion conditions need to be adjusted in order to achieve stable combustion. In this study, a gas that has the same characteristics as syngas, such as low heating value (LHV), was produced by mixing N{sub 2} with compressed natural gas (CNG). In addition, this study investigates the combustion characteristics of syngas when it is mixed with hydrogen in a ratio ranging from 10% to 30% with a constant LHV of total gas.

  9. CONCEPTUAL DESIGN AND ECONOMICS OF A NOMINAL 500 MWe SECOND-GENERATION PFB COMBUSTION PLANT

    Energy Technology Data Exchange (ETDEWEB)

    A. Robertson; H. Goldstein; D. Horazak; R. Newby

    2003-09-01

    Research has been conducted under United States Department of Energy Contract DE-AC21-86MC21023 to develop a new type of coal-fired plant for electric power generation. This new type of plant, called a Second Generation Pressurized Fluidized Bed Combustion Plant (2nd Gen PFB), offers the promise of efficiencies greater than 48 percent, with both emissions and a cost of electricity that are significantly lower than those of conventional pulverized coal-fired (PC) plants with wet flue gas desulfurization. The 2nd Gen PFB plant incorporates the partial gasification of coal in a carbonizer, the combustion of carbonizer char in a pressurized circulating fluidized bed boiler, and the combustion of carbonizer syngas in a gas turbine combustor to achieve gas turbine inlet temperatures of 2300 F and higher. A conceptual design and an economic analysis was previously prepared for this plant. When operating with a Siemens Westinghouse W501F gas turbine, a 2400psig/1000 F/1000 F/2-1/2 in. Hg. steam turbine, and projected carbonizer, PCFB, and topping combustor performance data, the plant generated 496 MWe of power with an efficiency of 44.9 percent (coal higher heating value basis) and a cost of electricity 22 percent less than a comparable PC plant. The key components of this new type of plant have been successfully tested at the pilot plant stage and their performance has been found to be better than previously assumed. As a result, the referenced conceptual design has been updated herein to reflect more accurate performance predictions together with the use of the more advanced Siemens Westinghouse W501G gas turbine. The use of this advanced gas turbine, together with a conventional 2400 psig/1050 F/1050 F/2-1/2 in. Hg. steam turbine increases the plant efficiency to 48.2 percent and yields a total plant cost of $1,079/KW (January 2002 dollars). The cost of electricity is 40.7 mills/kWh, a value 12 percent less than a comparable PC plant.

  10. Combustion Stability of the Gas Generator Assembly from J-2X Engine E10001 and Powerpack Tests

    Science.gov (United States)

    Hulka, J. R.; Kenny, R. L.; Casiano, M. J.

    2013-01-01

    Testing of a powerpack configuration (turbomachinery and gas generator assembly) and the first complete engine system of the liquid oxygen/liquid hydrogen propellant J-2X rocket engine have been completed at the NASA Stennis Space Center. The combustion stability characteristics of the gas generator assemblies on these two systems are of interest for reporting since considerable effort was expended to eliminate combustion instability during early development of the gas generator assembly with workhorse hardware. Comparing the final workhorse gas generator assembly development test data to the powerpack and engine system test data provides an opportunity to investigate how the nearly identical configurations of gas generator assemblies operate with two very different propellant supply systems one the autonomous pressure-fed test configuration on the workhorse development test stand, the other the pump-fed configurations on the powerpack and engine systems. The development of the gas generator assembly and the elimination of the combustion instability on the pressure-fed workhorse test stand have been reported extensively in the two previous Liquid Propulsion Subcommittee meetings 1-7. The powerpack and engine system testing have been conducted from mid-2011 through 2012. All tests of the powerpack and engine system gas generator systems to date have been stable. However, measureable dynamic behavior, similar to that observed on the pressure-fed test stand and reported in Ref. [6] and attributed to an injection-coupled response, has appeared in both powerpack and engine system tests. As discussed in Ref. [6], these injection-coupled responses are influenced by the interaction of the combustion chamber with a branch pipe in the hot gas duct that supplies gaseous helium to pre-spin the turbine during the start transient. This paper presents the powerpack and engine system gas generator test data, compares these data to the development test data, and provides additional

  11. Comparative thermogravimetric analyses of co-combustion of textile dyeing sludge and sugarcane bagasse in carbon dioxide/oxygen and nitrogen/oxygen atmospheres: Thermal conversion characteristics, kinetics, and thermodynamics.

    Science.gov (United States)

    Xie, Wenhao; Wen, Shaoting; Liu, Jingyong; Xie, Wuming; Kuo, Jiahong; Lu, Xingwen; Sun, Shuiyu; Chang, Kenlin; Buyukada, Musa; Evrendilek, Fatih

    2018-05-01

    Thermodynamic and kinetic parameters of co-combustion of textile dyeing sludge (TDS) and sugarcane bagasse (SB) were studied using thermogravimetric analysis in CO 2 /O 2 and N 2 /O 2 atmospheres. Our results showed that the comprehensive combustion characteristic index (CCI) of the blends was improved by 1.71-4.32 times. With the increased O 2 concentration, co-combustion peak temperature decreased from 329.7 to 318.2 °C, with an increase in its maximum weight loss rate from 10.04 to 14.99%/min and its CCI by 1.31 times (β = 20 °C·min -1 ). To evaluate the co-combustion characteristics, thermodynamic and kinetic parameters (entropy, Gibbs free energy and enthalpy changes, and apparent activation energy) were obtained in the five atmospheres. The lowest apparent activation energy of the TB64 blend was obtained in oxy-fuel atmosphere (CO 2 /O 2  = 7/3). Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. ANALYSIS AND CONTROL OF HYDROCARBONS GENERATED IN THE COMBUSTION OF PET WASTES

    Directory of Open Access Journals (Sweden)

    Joner Oliveira Alves

    2012-12-01

    Full Text Available Brazilian production of PET (polyethylene terephthalate in 2010 was of 505,000 tones. The PET waste may be used to generate energy by controlled burning. In this study, emissions of light hydrocarbons generated during combustion of these wastes are characterized. Samples of post-consumer PET bottles were inserted in an electric furnace at temperatures of 600, 800 and 1000°C under an atmosphere of 15% O2 and 85% N2. The effluents were subjected to a SiC filter and channeled into the second furnace at 1000°C. Stainless steel meshes were placed in the second furnace in order to work as catalyst. Gas chromatography is used to evaluate the effluent with and without the catalyst use, wherein is showed a significant reduction in the emissions using the meshes. Results allow a characterization of the hydrocarbons generated during the controlled burning of PET waste providing information for control and recovery of these gases emissions

  13. Profiling 5-tolyltriazole biodegrading sludge communities using next-generation sequencing and denaturing gradient gel electrophoresis.

    Science.gov (United States)

    Herzog, Bastian; Dötsch, Andreas; Lemmer, Hilde; Horn, Harald; Müller, Elisabeth

    2017-12-01

    Efficient biodegradation of 5-tolyltriazole (5-TTri) in wastewater treatment would minimize its potential detrimental effects on aquatic systems. Therefore, in order to profile 5-TTri biodegrading activated sludge communities (ASC) by DGGE and NGS, acclimation experiments with (i) easily degradable substrates, and (ii) various complex substrates mimicking wastewater conditions were performed. DGGE revealed four genera: Aminobacter (family Phyllobacteriaceae), Flavobacterium (family Flavobacteriaceae), Pseudomonas (family Pseudomonaceae), and Hydrogenophaga (family Comamonadaceae). Metagenomics (DNA) revealed the dominant families Alcaligenaceae, Pseudomonadaceae and Comamonadaceae that also represented the most active families at the RNA level (metatranscriptomics), which might indicate their importance for 5-TTri biodegradation. ASC acclimation and the composition of the substrate significantly affected 5-TTri biodegradation and the development of biodegrading communities. Using acetate only, a moderate 5-TTri degrading community was detected with a very low biodiversity and Pseudomonas spp. as dominant organisms. In contrast, setups fed 'sludge supernatant' (a complex substrate) efficiently biodegraded 5-TTri and formed a more diverse microbial community but with Hydrogenophaga spp. as the dominant group. Finally, a hypothetical 5-TTri biodegradation pathway was constructed based exclusively on the detected, biodegradation-related, Hydrogenophaga spp. genes. Copyright © 2017 Elsevier GmbH. All rights reserved.

  14. Zinc chloride as a coagulant for textile dyes and treatment of generated dye sludge under the solid state fermentation: hybrid treatment strategy.

    Science.gov (United States)

    Kadam, Avinash A; Lade, Harshad S; Lee, Dae Sung; Govindwar, Sanjay P

    2015-01-01

    Dye sludge generation is major drawback of coagulation process. Efficient hybrid technology by combining coagulation and solid state fermentation (SSF) has capacity to solve generated dye sludge problem. Coagulation of 100mg/L Reactive Red 120 (RR120) using ZnCl2 showed 99% color removal. Mixture of textile dyes (MTD) and textile wastewater (TW) showed 96% and 98% ADMI (American Dye Manufacturing Institute) removal after coagulation by ZnCl2. 92% and 94% ADMI removal from MTD and TW dye sludge and 96% decolorization of RR120 sludge was observed respectively by developed microbial consortium (DCM) in 72h under SSF. Scale up of coagulation process by coagulation reactor (CR) having 50L capacity operated for 30min/cycle. CR showed average 94% ADMI removal from TW in 10 successive cycles. Scale up of SSF composting bioreactor (CB) showed complete dye removal from dye sludge obtained from CR (500L of TW) in 30days. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Modeling and Simulation of a Free-Piston Engine with Electrical Generator Using HCCI Combustion

    Science.gov (United States)

    Alrbai, Mohammad

    Free-piston engines have the potential to challenge the conventional crankshaft engines by their design simplicity and higher operational efficiency. Many studies have been performed to overcome the limitations of the free-piston devices especially the stability and control issues. The investigations within the presented dissertation aim to satisfy many objectives by employing the approach of chemical kinetics to present the combustion process in the free-piston engine. This approach in addition to its advanced accuracy over the empirical methods, it has many other features like the ability to analyze the engine emissions. The effect of the heat release rate (HRR) on the engine performance is considered as the main objective. Understanding the relation between the HRR and the piston dynamics helps in enhancing the system efficiency and identifying the parameters that affect the overall performance. The dissertation covers some other objectives that belongs to the combustion phasing. Exhaust gas recirculation (EGR), equivalence ratio and the intake temperature represent the main combustion parameters, which have been discussed in this dissertation. To obtain the stability in system performance, the model requires a proper controller to simulate the operation and manage the different system parameters; for this purpose, different controlling techniques have been employed. In addition, the dissertation considers some other topics like engine emissions, fuels and fuels mechanisms. The model of the study describes the processes within a single cylinder, two stroke engine, which includes springs to support higher frequencies, reduce cyclic variations and sustain the engine compression ratio. An electrical generator presents the engine load; the generator supports different load profiles and play the key role in controlling the system. The 1st law of thermodynamics and Newton's 2nd law are applied to couple the piston dynamics with the engine thermodynamics. The model

  16. Analysis of biomass and waste gasification lean syngases combustion for power generation using spark ignition engines.

    Science.gov (United States)

    Marculescu, Cosmin; Cenuşă, Victor; Alexe, Florin

    2016-01-01

    The paper presents a study for food processing industry waste to energy conversion using gasification and internal combustion engine for power generation. The biomass we used consisted in bones and meat residues sampled directly from the industrial line, characterised by high water content, about 42% in mass, and potential health risks. Using the feedstock properties, experimentally determined, two air-gasification process configurations were assessed and numerically modelled to quantify the effects on produced syngas properties. The study also focused on drying stage integration within the conversion chain: either external or integrated into the gasifier. To comply with environmental regulations on feedstock to syngas conversion both solutions were developed in a closed system using a modified down-draft gasifier that integrates the pyrolysis, gasification and partial oxidation stages. Good quality syngas with up to 19.1% - CO; 17% - H2; and 1.6% - CH4 can be produced. The syngas lower heating value may vary from 4.0 MJ/Nm(3) to 6.7 MJ/Nm(3) depending on process configuration. The influence of syngas fuel properties on spark ignition engines performances was studied in comparison to the natural gas (methane) and digestion biogas. In order to keep H2 molar quota below the detonation value of ⩽4% for the engines using syngas, characterised by higher hydrogen fraction, the air excess ratio in the combustion process must be increased to [2.2-2.8]. The results in this paper represent valuable data required by the design of waste to energy conversion chains with intermediate gas fuel production. The data is suitable for Otto engines characterised by power output below 1 MW, designed for natural gas consumption and fuelled with low calorific value gas fuels. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Biomass gasification for electricity generation with internal combustion engines. Process efficiency

    International Nuclear Information System (INIS)

    Lesme-Jaén, René; Garcia Faure, Luis; Recio Recio, Angel; Oliva Ruiz, Luis; Pajarín Rodríguez, Juan; Revilla Suarez, Dennis

    2015-01-01

    Biomass is a renewable source of energy worldwide increased prospects for its potential and its lower environmental impact compared to fossil fuels. By processes and energy conversion technologies it is possible to obtain fuels in solid, liquid and gaseous form from any biomass. The biomass gasification is the thermal conversion thereof into a gas, which can be used for electricity production with the use of internal combustion engines with a certain level of efficiency, which depends on the characteristics of biomass and engines used. In this work the evaluation of thermal and overall efficiency of the gasification in Integrated Forestry Enterprise of Santiago de Cuba, designed to generate electricity from waste from the forest industry is presented. Is a downdraft gasifier reactor, COMBO-80 model and engine manufacturing Hindu (diesel) model Leyland modified to work with producer gas. The evaluation was carried out for different loads (electric power generated) engine from experimental measurements of flow and composition of the gas supplied to the engine. The results show that the motor operates with a thermal efficiency in the range of 20-32% with an overall efficiency between 12-25%. (full text)

  18. Bioelectricity Generation and Bioremediation of an Azo-Dye in a Microbial Fuel Cell Coupled Activated Sludge Process

    Science.gov (United States)

    Khan, Mohammad Danish; Abdulateif, Huda; Ismail, Iqbal M.; Sabir, Suhail; Khan, Mohammad Zain

    2015-01-01

    Simultaneous bioelectricity generation and dye degradation was achieved in the present study by using a combined anaerobic-aerobic process. The anaerobic system was a typical single chambered microbial fuel cell (SMFC) which utilizes acid navy blue r (ANB) dye along with glucose as growth substrate to generate electricity. Four different concentrations of ANB (50, 100, 200 and 400 ppm) were tested in the SMFC and the degradation products were further treated in an activated sludge post treatment process. The dye decolorization followed pseudo first order kinetics while the negative values of the thermodynamic parameter ∆G (change in Gibbs free energy) shows that the reaction proceeds with a net decrease in the free energy of the system. The coulombic efficiency (CE) and power density (PD) attained peak values at 10.36% and 2,236 mW/m2 respectively for 200 ppm of ANB. A further increase in ANB concentrations results in lowering of cell potential (and PD) values owing to microbial inhibition at higher concentrations of toxic substrates. Cyclic voltammetry studies revealed a perfect redox reaction was taking place in the SMFC. The pH, temperature and conductivity remain 7.5–8.0, 27(±2°C and 10.6–18.2 mS/cm throughout the operation. The biodegradation pathway was studied by the gas chromatography coupled with mass spectroscopy technique, suggested the preferential cleavage of the azo bond as the initial step resulting in to aromatic amines. Thus, a combined anaerobic-aerobic process using SMFC coupled with activated sludge process can be a viable option for effective degradation of complex dye substrates along with energy (bioelectricity) recovery. PMID:26496083

  19. A Comprehensive Insight into Tetracycline Resistant Bacteria and Antibiotic Resistance Genes in Activated Sludge Using Next-Generation Sequencing

    OpenAIRE

    Huang, Kailong; Tang, Junying; Zhang, Xu-Xiang; Xu, Ke; Ren, Hongqiang

    2014-01-01

    In order to comprehensively investigate tetracycline resistance in activated sludge of sewage treatment plants, 454 pyrosequencing and Illumina high-throughput sequencing were used to detect potential tetracycline resistant bacteria (TRB) and antibiotic resistance genes (ARGs) in sludge cultured with different concentrations of tetracycline. Pyrosequencing of 16S rRNA gene revealed that tetracycline treatment greatly affected the bacterial community structure of the sludge. Nine genera cons...

  20. Electricity generation and in situ phosphate recovery from enhanced biological phosphorus removal sludge by electrodialysis membrane bioreactor.

    Science.gov (United States)

    Geng, Yi-Kun; Wang, Yunkun; Pan, Xin-Rong; Sheng, Guo-Ping

    2018-01-01

    In this study, a novel electrodialysis membrane bioreactor was used for EBPR sludge treatment for energy and phosphorus resource recovery simultaneously. After 30days stable voltage outputting, the maximum power density reached 0.32W/m 3 . Over 90% of phosphorus in EBPR sludge was released while about 50% of phosphorus was concentrated to 4mmol/L as relatively pure phosphate solution. Nitrogen could be removed from EBPR sludge by desalination and denitrification processes. This study provides an optimized way treating sludge for energy production and in situ phosphorus recovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Converting existing Internal Combustion Generator (ICG) systems into HESs in standalone applications

    International Nuclear Information System (INIS)

    Perera, A.T.D.; Attalage, R.A.; Perera, K.K.C.K.; Dassanayake, V.P.C.

    2013-01-01

    Graphical abstract: - Highlights: • Obtained Pareto fronts of LEC, power supply reliability (PSR) and ICC/GHG emission. • Pareto surface was observed for smaller ICGs when considering LEC–PSR–GHG. • Shape of the LEC–PSR–ICC Pareto front gradually changes with ICG capacity. • Importance of multi-criterion decision-making after multi objective optimization. - Abstract: Expanding existing Internal Combustion Generator (ICG) systems by combining renewable energy sources is getting popular due to global concern on emission of green house gases (GHG) and increasing fossil fuel costs. Life cycle cost, initial capital cost (ICC), power supply reliability of the system, and GHG emission by ICG are factors to be considered in this process. Pareto front of Levelized Energy Cost (LEC)–Unmet Load Fraction (ULF)–GHG emission was taken in this study for four different expansion scenarios. Furthermore, Pareto front of ICC–LE–ULF was taken for three different expansion scenarios in order to analyze the impact of renewable energy integration. The results clearly depict that characteristics of the Pareto front varies with the scale of expansion and objectives taken for the optimization. A detailed analysis was conducted for a scale up problem with a 4 kVA ICG by using the Pareto fronts obtained

  2. Design of the steam generator in an energy conversion system based on the aluminum combustion with water

    International Nuclear Information System (INIS)

    Mercati, Stefano; Milani, Massimo; Montorsi, Luca; Paltrinieri, Fabrizio

    2012-01-01

    Highlights: ► Development of a numerical approach for the analysis of a co-generation system based on the aluminum water reaction. ► Construction of system operating maps for estimating the system behavior. ► Comparison of two different designs of the steam generator for the system. ► Definition of the operating range where each configuration provides the best performance. -- Abstract: The paper shows the preliminary design of the superheated steam generator to be used in a novel hydrogen production and energy conversion system based on the combustion of aluminum particles with water. The system is aimed at producing hydrogen and pressurized superheated steam, using the heat released by the Al–H 2 O reaction. The interest on this type of technology arises because of the possibility of obtaining hydrogen with very low pollutant and greenhouse gas emissions, compared to the traditional hydrogen production systems, such as the steam reforming from methane. The analysis of the combustion chamber and the heat recovery system is carried out by means of a lumped and distributed parameter numerical approach. The multi phase and gas mixture theoretical principles are used both to characterize the mass flow rate and the heat release in the combustion chamber and within the heat exchangers in order to relate the steam generator performance to the system operating parameters. Finally, the influence of the steam generator performance on the whole energy conversion system behavior is addressed, with particular care to the evaluation of the total power and efficiency variation with the combustion parameters.

  3. Research on vitrification technology to immobilize radioactive sludge generated from Fukushima Daiichi power plant. Enhanced glass medium

    International Nuclear Information System (INIS)

    Amamoto, Ippei; Kobayashi, Hidekazu; Kitamura, Naoto; Takebe, Hiromichi; Mitamura, Naoki; Tsuzuki, Tatsuya; Fukayama, Daigen; Nagano, Yuichi; Jantzen, Tatjana; Hack, Klaus

    2016-01-01

    The search for an enhanced glass medium to immobilize the sludge at the Fukushima Daiichi Nuclear Power Plant is our main purpose. The iron phosphate glass (IPG) is a potential candidate as we set about assessing it by means of theoretical and experimental investigation. Based on the results of this study, the IPG showed favorable characteristics as a vitrification medium for the sludge. (author)

  4. Next Generation Pressurized Oxy-Coal Combustion: High Efficiency and No Flue Gas Recirculation

    Energy Technology Data Exchange (ETDEWEB)

    Rue, David

    2013-09-30

    The Gas Technology Institute (GTI) has developed a pressurized oxy-coal fired molten bed boiler (MBB) concept, in which coal and oxygen are fired directly into a bed of molten coal slag through burners located on the bottom of the boiler and fired upward. Circulation of heat by the molten slag eliminates the need for a flue gas recirculation loop and provides excellent heat transfer to steam tubes in the boiler walls. Advantages of the MBB technology over other boilers include higher efficiency (from eliminating flue gas recirculation), a smaller and less expensive boiler, modular design leading to direct scalability, decreased fines carryover and handling costs, smaller exhaust duct size, and smaller emissions control equipment sizes. The objective of this project was to conduct techno-economic analyses and an engineering design of the MBB project and to support this work with thermodynamic analyses and oxy-coal burner testing. Techno-economic analyses of GTI’s pressurized oxy-coal fired MBB technology found that the overall plant with compressed CO2 has an efficiency of 31.6%. This is a significant increase over calculated 29.2% efficiency of first generation oxy-coal plants. Cost of electricity (COE) for the pressurized MBB supercritical steam power plant with CO2 capture and compression was calculated to be 134% of the COE for an air-coal supercritical steam power plant with no CO2 capture. This compares positively with a calculated COE for first generation oxy-coal supercritical steam power plants with CO2 capture and compression of 164%. The COE for the MBB power plant is found to meet the U.S. Department of Energy (DOE) target of 135%, before any plant optimization. The MBB power plant was also determined to be simpler than other oxy-coal power plants with a 17% lower capital cost. No other known combustion technology can produce higher efficiencies or lower COE when CO2 capture and compression are included. A thermodynamic enthalpy and exergy analysis

  5. Equation for Combustion Noise

    Science.gov (United States)

    Liu, T. M.

    1982-01-01

    Mathematical relationship derived for interactions between turbulent flame and combustion noise. Relationship is rigorous theoretical correlation of combustion noise and combustion process. Establishes foundation for acoustic measurements as tool for investigating structure of turbulent flames. Mathematical relationship is expected to aid researchers in field of noise generated by combustion.

  6. Sewage sludge as a biomass energy source

    Directory of Open Access Journals (Sweden)

    Pavel Kolat

    2013-01-01

    Full Text Available The major part of the dry matter content of sewage sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary microbiological sludge. The sludge also contains a substantive amount of inorganic material and a small amount of toxic components. There are many sludge-management options in which production of energy is one of the key treatment steps. The most important options are anaerobic digestion, co-digestion, incineration in combination with energy recovery and co-incineration in coal-fired power plants. The goal of our applied research is to verify, if the sludge from waste water treatment plants may be used as a biomass energy source in respect of the EU legislation, which would comply with emission limits or the proposal of energy process optimizing the preparation of coal/sludge mixture for combustion in the existing fluid bed boilers in the Czech Republic. The paper discusses the questions of thermal usage of mechanically drained stabilized sewage sludge from the waste water treatment plants in the boiler with circulated fluid layer. The paper describes methods of thermal analysis of coal, sewage sludge and its mixtures, mud transport to the circulating fluidised bed boiler, effects on efficiency, operational reliability of the combustion equipment, emissions and solid combustion residues.

  7. Technologies for the treatment of the sulfur dioxide and nitrogen oxides generated by the combustion in open chamber; Tecnologias para el tratamiento de dioxido de azufre y oxidos de nitrogeno generados por la combustion en camara abierta

    Energy Technology Data Exchange (ETDEWEB)

    Salazar Villalpando, Maria Dolores [Instituto Mexicano del Petroleo, Mexico, D. F. (Mexico)

    1992-12-31

    In general terms, there are only three ways of avoiding the sulfur dioxide and the nitrogen oxides, generated by the combustion in open chamber, from contaminating the air; the first one is utilizing low sulfur and nitrogen content fuels, the second one is by controlling the parameters that affect the combustion and the third one to treat and/or clean the gases before exhausting them to the air. In this document, some of the treatments for diminishing the pollutant emissions generated by the combustion in open chamber, are presented. [Espanol] En terminos generales, solo existen 3 maneras de evitar que el dioxido de azufre y oxidos de nitrogeno generados por la combustion en camara abierta sigan contaminando el aire, la primera es utilizar un combustible de bajo contenido de azufre y nitrogeno, la segunda es controlar los parametros que afectan la combustion, y la tercera es tratar y/o limpiar los gases antes de emitirlos a la atmosfera. En este documento se presentan algunos tratamientos para disminuir las emisiones de contaminantes generados por la combustion en camara abierta.

  8. Co-combustion of automotive shredder residue (ASR) and sewage sludge with a mixture of industrial and household waste in an 20MW fluidized bed combustor; Samfoerbraenning av bilfluff, roetslam och avfall i en 20 MW fluidbaeddpanna - Studier av braenslesammansaettningens paaverkan paa belaeggningsbildning

    Energy Technology Data Exchange (ETDEWEB)

    Eskilsson, David; Johansson, Andreas; Johansson, Linda; Wikstroem-Blomqvist, Evalena

    2007-07-01

    In order to prevent a further increased use of resources and to decrease the environmental impact from landfills, organic wastes are today diverted towards material and energy recovery. This creates a waste market with an increasing number of waste fractions that needs to be treated properly. As an example, in Sweden it has recently been prohibited to landfill source separated combustible waste (2002) and organic waste (2005). Wastes as automotive shredder residue (ASR) and sewage sludge can no longer be landfilled and needs to be either material or energy recovered, which challenge the waste treatment sector. This work investigates the effects of ASR and sewage sludge co-combustion in a 20 MW Energy-from-Waste plant (bubbling fluidised bed). The long term objective of the work is to increase the fuel flexibility, the boiler availability and the power production. This report focus on boiler operation and combustion performance in terms of agglomeration, deposit rates and emissions. In addition to the tests with ASR and sewage sludge, repeated measurements were performed during normal load as a reference. The results show that the co-combusted fractions of ASR and sewage sludge, which on mass basis constituted 6 % and 15 % respectively, did not increase the risk for agglomeration or deposits on heat-exchanging surfaces. Instead, compared to the two reference cases, the deposit rates decreased when sewage sludge was added. Only minor variation in the emissions was seen between the different cases. The levels of I-TEQs were far below the legislated values in all cases

  9. Application of Foam-gel Technique to Control CO Exposure Generated During Spontaneous Combustion of Coal in Coal Mines.

    Science.gov (United States)

    Ren, Xing W; Wang, Feng Z; Guo, Qing; Zuo, Zhao B; Fang, Qi S

    2015-01-01

    In China, 47.3% of state-owned coal mines are located in coal seams that are prone to spontaneous combustion. The spontaneous combustion of coal is the main cause of the generation of a large amount of carbon monoxide, which can cause serious health issues to miners. A new technique using foam-gel formation was developed to effectively control the spontaneous combustion of coal. The gel can capture more than 90% of the water in the grout and at the same time the foam can cover dangerous areas in the goaf by stacking and cooling of foam in all directions. In this study, a mechanism of foam-gel formation was introduced and the optimal proportions of additives were defined based on experiments of different foaming properties, gelling time and water loss rate as the main index parameters. The results of a field application in a coal mine promise that this new technique would effectively prevent coal oxidation in the goaf and reduce the generation of carbon monoxide.

  10. Co-combustion feasibility study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Handcock, D.J. [Clough, Harbour and Associates, Albany, NY (United States)

    1995-01-01

    This report investigates the technical and economic feasibility of co-combusting municipal sewage sludge produced by the Saratoga County Sewer District No. 1 with paper mill sludge produced by the Cottrell Paper Company, Encore Paper Company, International Paper Company, Mohawk Paper Mills, and TAGSONS Papers at the Saratoga County Sewer District No. 1`s secondary wastewater treatment plant and recovering any available energy products. The co-combustion facility would consist of sludge and wood chip storage and conveying systems, belt filter presses, screw presses, fluidized-bed incinerators, venturi scrubbers and tray cooling systems, ash dewatering facilities, heat recovery steam generators, gas-fired steam superheaters, and a back-pressure steam turbine system. Clean waste wood chips would be used as an auxiliary fuel in the fluidized-bed incinerators. It is recommended that the ash produced by the proposed facility be beneficially used, potentially as a raw material in the manufacture of cement and/or as an interim barrier layer in landfills.

  11. pH neutralization of the by-product sludge waste water generated from waste concrete recycling process using the carbon mineralization

    Science.gov (United States)

    Ji, Sangwoo; Shin, Hee-young; Bang, Jun Hwan; Ahn, Ji-Whan

    2017-04-01

    About 44 Mt/year of waste concrete is generated in South Korea. More than 95% of this waste concrete is recycled. In the process of regenerating and recycling pulmonary concrete, sludge mixed with fine powder generated during repeated pulverization process and water used for washing the surface and water used for impurity separation occurs. In this way, the solid matter contained in the sludge as a by-product is about 40% of the waste concrete that was input. Due to the cement component embedded in the concrete, the sludge supernatant is very strong alkaline (pH about 12). And it is necessary to neutralization for comply with environmental standards. In this study, carbon mineralization method was applied as a method to neutralize the pH of highly alkaline waste water to under pH 8.5, which is the water quality standard of discharged water. CO2 gas (purity 99%, flow rate 10ml/min.) was injected and reacted with the waste water (Ca concentration about 750mg/L) from which solid matter was removed. As a result of the experiment, the pH converged to about 6.5 within 50 minutes of reaction. The precipitate showed high whiteness. XRD and SEM analysis showed that it was high purity CaCO3. For the application to industry, it is needed further study using lower concentration CO2 gas (about 14%) which generated from power plant.

  12. Chemical characterization of bottom ashes generated during combustion of a Colombian mineral coal in a thermal power plant

    International Nuclear Information System (INIS)

    Pinheiro, H.S.; Nogueira, R.E.F.Q.; Lobo, C.J.S.; Nobre, A.I.S.; Sales, J.C.; Silva, C.J.M.

    2012-01-01

    Bottom ashes generated during combustion of a mineral coal from Colombia were characterized by X-ray fluorescence spectrometry and X-ray diffraction. The interest in this particular coal is due to the fact that it will be used by a thermal power plant in Ceara, Northeastern Brazil, where it could produce over 900 tons of different residues/combustion products every day. Results from Xray fluorescence allowed identification and quantification of elements present in the sample: silicon (59,17%), aluminum (13,17%), iron (10,74%), potassium (6,11%), titanium (2,91%), calcium (4,97%), sulphur (0,84%) and others (2,09%). The X-ray diffraction revealed patterns from silica, mullite, calcium sulphate and hydrated sodium. Results obtained so far indicate that the material is a potential raw-material for use in the formulation of ceramic components (author)

  13. Research of combustion in older generation spark-ignition engines in the condition of use leaded and unleaded petrol

    Directory of Open Access Journals (Sweden)

    Bulatović Željko M.

    2014-01-01

    Full Text Available This paper analyzes the potential problems in the exploitation of the older generation of spark-ignition engines with higher octane number of petrol (unleaded petrol BMB 95 than required (leaded petrol MB 86. Within the experimental tests on two different engines (STEYR-PUCH model 712 and GAZ 41 by applying piezoelectric pressure sensors integrated with the engine spark plugs, acceleration sensors (accelerometers and special electronic block connected with distributor, show that the cumulative first and second theoretical phase of combustion when petrol of higher octane number (BMB 95 is used lasts slightly longer than when the low-octane petrol MB 86 is used. For new petrol (BMB 95 higher optimal angles of pre-ignition have been determined by which better performances of the engine are achieved without a danger of the combustion with detonation (also called knocking.

  14. SID seeks sludge and foreign bodies in steam generator upper heads while CECIL robotically removes them

    International Nuclear Information System (INIS)

    Ashton, A.T.; Gay, J.

    1993-01-01

    The CECIL [Consolidated Edison Combined Inspection and Lancing] system provides a range of maintenance tools for cleaning the region between the tubesheet and the first support plate in steam generators. SID [Secondary Inspection Device] extends access to and inspection of the upper bundle region. Work is being done to combine CECIL and SID technology to inspect and hydraulically clean the upper bundle. (Author)

  15. Wasteless combined aggregate-coal-fired steam-generator/melting-converter

    International Nuclear Information System (INIS)

    Pioro, L.S.; Pioro, I.L.

    2003-01-01

    A method of reprocessing coal sludge and ash into granulate for the building industry in a combined wasteless aggregate-steam-generator/melting-converter was developed and tested. The method involves melting sludge and ash from coal-fired steam-generators of power plants in a melting-converter installed under the steam-generator, with direct sludge drain from the steam generator combustion chamber. The direct drain of sludge into converter allows burnup of coal with high ash levels in the steam-generator without an additional source of ignition (natural gas, heating oil, etc.). Specific to the melting process is the use of a gas-air mixture with direct combustion inside a melt. This feature provides melt bubbling and helps to achieve maximum heat transfer from combustion products to the melt, to improve mixing, to increase rate of chemical reactions and to improve the conditions for burning the carbon residue from the sludge and ash. The 'gross' thermal efficiency of the combined aggregate is about 93% and the converter capacity is about 18 t of melt in 100 min. The experimental data for different aspects of the proposed method are presented. The effective ash/charging materials feeding system is also discussed. The reprocessed coal ash and sludge in the form of granules can be used as fillers for concretes and as additives in the production of cement, bricks and other building materials

  16. Synthesis of lithium silicates generators of tritium by a modified method of combustion

    International Nuclear Information System (INIS)

    Cruz G, D.

    2003-01-01

    The ceramics of lithium have been proposed as generating materials of tritium through the following reaction: 6 Li + 1 n → 4 He + 3 H . In previous works carried out by Pfeiffer and collaborators, the lithium silicates generators of tritium were prepared using the following methods: reactions of solid state, precipitation and sol-gel synthesis. Although those methods have advantages, it is required of heating at high temperatures (900 C during four hours) to be able to obtain the crystalline compounds. Those products found in these works were diverse crystallization forms of the lithium silicates and of SiO 2 , such as, Li 2 SiO 3 , Li 2 Si 2 0 5 , Li 4 SiO 4 , and quartz (SiO 2 ). The combustion method uses exothermic reactions to take place ceramic compounds. The precursor solutions are mixtures of the nitrate of metal oxidizer and the fuels (urea, glycine, carbohydrazide). However the reported method in the literature, it is not useful to prepare lithium silicates, for what was modified using non oxidizers compounds. The lithium hydroxide (LiOH) and the silicic acid (H 2 SiO 3 ) they were the compounds non oxidizers used, and the urea (CH 4 N 2 O) it was the one fuel. They were carried out two series of experiments; inside the series 1 of experiments are varied the molar ratio of lithium hydroxide and urea (LiOH : H 2 SiO 3 = 1, 2 and 3, LiOH : CH 4 N 2 O = 1, 2, 3, 4 and 5) and the prepared mixtures were taken to one muffle previously preheated to a temperature of 450 C during 5 minutes. In the series 2 of experiments was studied the effect of the temperature and of the washed with distilled water in the prepared samples with the following molar ratios: LiOH : H 2 SiO 3 : CH 4 N 2 O = 1:1:3, 2:1:3, 3:1:3 and 3:1:6, those which were heated to temperatures from 450 C up to 750 C and were washed. The obtained samples were characterized by X-ray diffraction (XRD), Infrared spectroscopy (I S), semiquantitative elemental analysis (EDS) and Thermal gravimetric

  17. Small hazardous waste generators in developing countries: use of stabilization/solidification process as an economic tool for metal wastewater treatment and appropriate sludge disposal.

    Science.gov (United States)

    Silva, Marcos A R; Mater, Luciana; Souza-Sierra, Maria M; Corrêa, Albertina X R; Sperb, Rafael; Radetski, Claudemir M

    2007-08-25

    The aim of this study was to propose a profitable destination for an industrial sludge that can cover the wastewater treatment costs of small waste generators. Optimized stabilization/solidification technology was used to treat hazardous waste from an electroplating industry that is currently released untreated to the environment. The stabilized/solidified (S/S) waste product was used as a raw material to build concrete blocks, to be sold as pavement blocks or used in roadbeds and/or parking lots. The quality of the blocks containing a mixture of cement, lime, clay and waste was evaluated by means of leaching and solubility tests according to the current Brazilian waste regulations. Results showed very low metal leachability and solubility of the block constituents, indicating a low environmental impact. Concerning economic benefits from the S/S process and reuse of the resultant product, the cost of untreated heavy metal-containing sludge disposal to landfill is usually on the order of US$ 150-200 per tonne of waste, while 1tonne of concrete roadbed blocks (with 25% of S/S waste constitution) has a value of around US$ 100. The results of this work showed that the cement, clay and lime-based process of stabilization/solidification of hazardous waste sludge is sufficiently effective and economically viable to stimulate the treatment of wastewater from small industrial waste generators.

  18. Analysis regarding steam generator furnace's incident heat, temperature and composition of combustion gases; Analisis de calor incidente, temperatura y composicion de gases de combustion en hornos de generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Diego Marin, Antonio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    In order to obtain more precise evaluations of the combustion process in the furnace of a steam generator a suction pyrometer has been integrated to measure the temperature of the combustion gases; an ellipsoidal radiometer to measure the incident heat by thermal radiation in the water walls; a water cooled probe to determine the particle concentration, as well as a water cooled probe to determine the composition of the combustion gases present. This document clarifies the form of use of these instruments and their engineering specifications, simultaneously presenting an analysis that considers, unlike others, the internal conditions of the furnace to obtain a more precise evaluation of the efficiency that the combustion process presents and bases for the taking of preventive actions in specific zones of the furnace. Thus, the present work exhibits instruments and techniques of analysis to study the phenomena occurring within a steam generator. [Spanish] Con el fin de obtener evaluaciones mas precisas del proceso de combustion en el horno de un generador de vapor, se ha integrado un pirometro de succion para medir la temperatura de los gases de combustion; un radiometro elipsoidal para medir el calor incidente por radiacion termica en las paredes del agua; una sonda enfriada con agua para determinar la concentracion de particulas, asi como una sonda refrigerada con agua para determinar la composicion de los gases de combustion presentes. Este documento aclara la forma de uso de estos instrumentos y sus especificaciones tecnicas, a la vez que presenta un analisis que considera, a diferencia de otros, las condiciones internas del horno para obtener una evaluacion mas precisa sobre la eficiencia del proceso de combustion y bases para la toma de acciones preventivas en zonas especificas del horno. Asi, el presente trabajo exhibe instrumentos y tecnicas de analisis para estudiar los fenomenos que ocurren dentro de un generador de vapor.

  19. Distributed and micro-generation from biogas and agricultural application of sewage sludge: Comparative environmental performance analysis using life cycle approaches

    International Nuclear Information System (INIS)

    Sadhukhan, Jhuma

    2014-01-01

    Highlights: • 180,000 MJ biogas from 15.87 t sewage sludge supply 1 household electricity per year. • From the highest to the lowest avoided impacts: PEM FC 2 eq./MJ compared to natural gas. • 1 m 3 biogas production from ∼3.2 t sewage sludge AD can save 0.92 m 3 natural gas. • Digested matter causes eutrophication and toxicity potentials. - Abstract: The Feed-In-Tariff scheme in the UK has generated attractive economics in the investment for anaerobic digestion (AD) to convert sewage sludge into biogas and digested sludge for energy and agricultural applications, respectively. The biogas is a source of biomethane to replace natural gas in the gas grid system. Biogas can be utilised to generate combined heat and power (CHP) on-site, at household micro and distributed or community scales. These biogas CHP generation options can replace the equivalent natural gas based CHP generation options. Digested sludge can be transformed into fertiliser for agricultural application replacing inorganic N:P:K fertiliser. Biogas and digested matter yields are inter-dependent: when one increases, the other decreases. Hence, these various options need to be assessed for avoided life cycle impact potentials, to understand where greatest savings lie and in order to rank these options for informed decision making by water industries. To fill a gap in the information available to industry dealing with wastewater, the avoided emissions by various AD based technologies, in primary impact potentials that make a difference between various systems, have been provided in this paper. 1 m 3 biogas can save 0.92 m 3 natural gas. An average UK household (with a demand of 2 kWe) requires 180,000 MJ or 5000 Nm 3 or 4.76 t biogas per year, from 15.87 t sewage sludge processed through AD. The proton exchange membrane fuel cell (PEM FC) is suitable for building micro-generations; micro gas turbine (Micro GT), solid oxide fuel cell (SOFC) and SOFC-GT hybrid are suitable for distributed

  20. Climate impact and energy efficiency from electricity generation through anaerobic digestion or direct combustion of short rotation coppice willow

    International Nuclear Information System (INIS)

    Ericsson, Niclas; Nordberg, Åke; Sundberg, Cecilia; Ahlgren, Serina; Hansson, Per-Anders

    2014-01-01

    Highlights: • Using LCA, CHP from willow use in biogas was compared with direct combustion. • Direct combustion was ninefold more energy-efficient. • Biogas had a much greater cooling effect on global mean surface temperature. • The effects of soil carbon changes on temperature over time differed. • Biogas had long-term temperature effects, direct combustion short-term effects. - Abstract: Short rotation coppice willow is an energy crop used in Sweden to produce electricity and heat in combined heat and power plants. Recent laboratory-scale experiments have shown that SRC willow can also be used for biogas production in anaerobic digestion processes. Here, life cycle assessment is used to compare the climate impact and energy efficiency of electricity and heat generated by these measures. All energy inputs and greenhouse gas emissions, including soil organic carbon fluxes were included in the life cycle assessment. The climate impact was determined using time-dependent life cycle assessment methodology. Both systems showed a positive net energy balance, but the direct combustion system delivered ninefold more energy than the biogas system. Both systems had a cooling effect on the global mean surface temperature change. The cooling impact per hectare from the biogas system was ninefold higher due to the carbon returned to soil with the digestate. Compensating the lower energy production of the biogas system with external energy sources had a large impact on the result, effectively determining whether the biogas scenario had a net warming or cooling contribution to the global mean temperature change per kWh of electricity. In all cases, the contribution to global warming was lowered by the inclusion of willow in the energy system. The use of time-dependent climate impact methodology shows that extended use of short rotation coppice willow can contribute to counteract global warming

  1. A comprehensive study of combustion products generated from pulverized peat combustion in the furnace of BKZ-210-140F steam boiler

    Science.gov (United States)

    Kuzmin, V. A.; Zagrai, I. A.

    2017-11-01

    The experimental and theoretical study of combustion products has been carried out for the conditions of pulverized peat combustion in BKZ-210-140F steam boiler. Sampling has been performed in different parts of the boiler system in order to determine the chemical composition, radiative properties and dispersity of slag and ash particles. The chemical composition of particles was determined using the method of x-ray fluorescence analysis. Shapes and sizes of the particles were determined by means of electron scanning microscopy. The histograms and the particle size distribution functions were computed. The calculation of components of the gaseous phase was based on the combustion characteristics of the original fuel. The software package of calculation of thermal radiation of combustion products from peat combustion was used to simulate emission characteristics (flux densities and emissivity factors). The dependence of emission characteristics on the temperature level and on the wavelength has been defined. On the basis of the analysis of emission characteristics the authors give some recommendations how to determine the temperature of peat combustion products in the furnace of BKZ-210-140F steam boiler. The findings can be used to measure the combustion products temperature, support temperature control in peat combustion and solve the problem of boiler furnace slagging.

  2. A Comprehensive Insight into Tetracycline Resistant Bacteria and Antibiotic Resistance Genes in Activated Sludge Using Next-Generation Sequencing

    Science.gov (United States)

    Huang, Kailong; Tang, Junying; Zhang, Xu-Xiang; Xu, Ke; Ren, Hongqiang

    2014-01-01

    In order to comprehensively investigate tetracycline resistance in activated sludge of sewage treatment plants, 454 pyrosequencing and Illumina high-throughput sequencing were used to detect potential tetracycline resistant bacteria (TRB) and antibiotic resistance genes (ARGs) in sludge cultured with different concentrations of tetracycline. Pyrosequencing of 16S rRNA gene revealed that tetracycline treatment greatly affected the bacterial community structure of the sludge. Nine genera consisting of Sulfuritalea, Armatimonas, Prosthecobacter, Hyphomicrobium, Azonexus, Longilinea, Paracoccus, Novosphingobium and Rhodobacter were identified as potential TRB in the sludge. Results of qPCR, molecular cloning and metagenomic analysis consistently indicated that tetracycline treatment could increase both the abundance and diversity of the tet genes, but decreased the occurrence and diversity of non-tetracycline ARG, especially sulfonamide resistance gene sul2. Cluster analysis showed that tetracycline treatment at subinhibitory concentrations (5 mg/L) was found to pose greater effects on the bacterial community composition, which may be responsible for the variations of the ARGs abundance. This study indicated that joint use of 454 pyrosequencing and Illumina high-throughput sequencing can be effectively used to explore ARB and ARGs in the environment, and future studies should include an in-depth investigation of the relationship between microbial community, ARGs and antibiotics in sewage treatment plant (STP) sludge. PMID:24905407

  3. A Comprehensive Insight into Tetracycline Resistant Bacteria and Antibiotic Resistance Genes in Activated Sludge Using Next-Generation Sequencing

    Directory of Open Access Journals (Sweden)

    Kailong Huang

    2014-06-01

    Full Text Available In order to comprehensively investigate tetracycline resistance in activated sludge of sewage treatment plants, 454 pyrosequencing and Illumina high-throughput sequencing were used to detect potential tetracycline resistant bacteria (TRB and antibiotic resistance genes (ARGs in sludge cultured with different concentrations of tetracycline. Pyrosequencing of 16S rRNA gene revealed that tetracycline treatment greatly affected the bacterial community structure of the sludge. Nine genera consisting of Sulfuritalea, Armatimonas, Prosthecobacter, Hyphomicrobium, Azonexus, Longilinea, Paracoccus, Novosphingobium and Rhodobacter were identified as potential TRB in the sludge. Results of qPCR, molecular cloning and metagenomic analysis consistently indicated that tetracycline treatment could increase both the abundance and diversity of the tet genes, but decreased the occurrence and diversity of non-tetracycline ARG, especially sulfonamide resistance gene sul2. Cluster analysis showed that tetracycline treatment at subinhibitory concentrations (5 mg/L was found to pose greater effects on the bacterial community composition, which may be responsible for the variations of the ARGs abundance. This study indicated that joint use of 454 pyrosequencing and Illumina high-throughput sequencing can be effectively used to explore ARB and ARGs in the environment, and future studies should include an in-depth investigation of the relationship between microbial community, ARGs and antibiotics in sewage treatment plant (STP sludge.

  4. A comprehensive insight into tetracycline resistant bacteria and antibiotic resistance genes in activated sludge using next-generation sequencing.

    Science.gov (United States)

    Huang, Kailong; Tang, Junying; Zhang, Xu-Xiang; Xu, Ke; Ren, Hongqiang

    2014-06-05

    In order to comprehensively investigate tetracycline resistance in activated sludge of sewage treatment plants, 454 pyrosequencing and Illumina high-throughput sequencing were used to detect potential tetracycline resistant bacteria (TRB) and antibiotic resistance genes (ARGs) in sludge cultured with different concentrations of tetracycline. Pyrosequencing of 16S rRNA gene revealed that tetracycline treatment greatly affected the bacterial community structure of the sludge. Nine genera consisting of Sulfuritalea, Armatimonas, Prosthecobacter, Hyphomicrobium, Azonexus, Longilinea, Paracoccus, Novosphingobium and Rhodobacter were identified as potential TRB in the sludge. Results of qPCR, molecular cloning and metagenomic analysis consistently indicated that tetracycline treatment could increase both the abundance and diversity of the tet genes, but decreased the occurrence and diversity of non-tetracycline ARG, especially sulfonamide resistance gene sul2. Cluster analysis showed that tetracycline treatment at subinhibitory concentrations (5 mg/L) was found to pose greater effects on the bacterial community composition, which may be responsible for the variations of the ARGs abundance. This study indicated that joint use of 454 pyrosequencing and Illumina high-throughput sequencing can be effectively used to explore ARB and ARGs in the environment, and future studies should include an in-depth investigation of the relationship between microbial community, ARGs and antibiotics in sewage treatment plant (STP) sludge.

  5. Treatment of synthetic wastewater and hog waste with reduced sludge generation by the multi-environment BioCAST technology.

    Science.gov (United States)

    Yerushalmi, L; Alimahmoodi, M; Mulligan, C N

    2013-01-01

    Simultaneous removal of carbon, nitrogen and phosphorus was examined along with reduced generation of biological sludge during the treatment of synthetic wastewater and hog waste by the BioCAST technology. This new multi-environment wastewater treatment technology contains both suspended and immobilized microorganisms, and benefits from the presence of aerobic, microaerophilic, anoxic and anaerobic conditions for the biological treatment of wastewater. The influent concentrations during the treatment of synthetic wastewater were 1,300-4,000 mg chemical oxygen demand (COD)/L, 42-115 mg total nitrogen (TN)/L, and 19-40 mg total phosphorus (TP)/L. The removal efficiencies reached 98.9, 98.3 and 94.1%, respectively, for carbon, TN and TP during 225 days of operation. The removal efficiencies of carbon and nitrogen showed a minimal dependence on the nitrogen-to-phosphorus (N/P) ratio, while the phosphorus removal efficiency showed a remarkable dependence on this parameter, increasing from 45 to 94.1% upon the increase of N/P ratio from 3 to 4.5. The increase of TN loading rate had a minimal impact on COD removal rate which remained around 1.7 kg/m(3) d, while it contributed to increased TP removal efficiency. The treatment of hog waste with influent COD, TN and TP concentrations of 960-2,400, 143-235 and 25-57 mg/L, respectively, produced removal efficiencies up to 89.2, 69.2 and 47.6% for the three contaminants, despite the inhibitory effects of this waste towards biological activity. The treatment system produced low biomass yields with average values of 3.7 and 8.2% during the treatment of synthetic wastewater and hog waste, respectively.

  6. Suitability of aquatic biomass from Lake Toba (North Sumatra, Indonesia) for energy generation by combustion process

    Science.gov (United States)

    Brunerová, A.; Roubík, H.; Herák, D.

    2017-09-01

    Several aquatic plant species were identified as aquatic pollution of Lake Toba, North Sumatra (Indonesia); specifically, water hyacinth Eichhornia crassipes and aquatic weeds Hydrilla verticillata and Myriophyllum spicatum due to their high biomass yield which causes impenetrable mats at the bottom and surface of the lake. That complicates other vegetation growth and utilization of water areas for fishing or recreation. In attempt to clean the lake and prevent plants expansion, great amount of plants populations are removed from water but subsequent efficient utilization of such aquatic biomass is not ensured. Present research investigated energy potential of aquatic biomass originated from mentioned aquatic plants from Lake Toba and its possible utilization for energy production by direct combustion. Performed chemical analysis contained from determination of moisture, ash and volatile matter contents and calorific values. Evaluation of results proved highest suitability and energy potential of Eichhornia crassipes with gross calorific value (GCV) 16.31 MJ·kg-1, followed by Hydrilla verticillata with GCV 15.24 MJ·kg-1. Samples of Myriophyllum spicatum exhibited unsatisfactory results due to its low GCV (11.27 MJ·kg-1) in combination with high ash content (36.99%) which indicates complications during combustion, thus, low energy production efficiency and overall unsuitability for combustion purposes.

  7. Study into the status of co-combustion of sewage sludge, biomass and household refuse in coal-fired power stations. Final report; Untersuchungen zum Stand der Mitverbrennung von Klaerschlamm, Hausmuell und Biomasse in Kohlekraftwerken. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Hein, K.R.G.; Spliethoff, H.; Scheurer, W. [Stuttgart Univ. (Germany). Inst. fuer Verfahrenstechnik und Dampfkesselwesen; Seifert, H.; Richers, U. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer technische Chemie - Thermische Abfallbehandlung

    2000-03-01

    The co-combustion of wastes in power stations is an additional option for the thermal treatment of certain waste materials and thus for complying with the specifications of the German TA-Siedlungsabfall (technical directive on disposal of municipal solid waste). The present investigation compiles the status of knowledge about co-combustion of sewage sludge, biomass and selected waste materials in coal-fired power stations. The results are meant to provide extensive assistance to evaluate the processes and thus to contribute to sort out uncertainties, both on the part of power plant operators and of the authorities. Based on the information acquired, the report shall point out the gaps in knowledge, the further need for research and development and the need for action conerning the authorities. By enquiries at disposal enterprises, power station operators as well as authorities, the literature work was completed and a comprehensive view of the current situation in Germany elaborated. The report points out the legal conditions of co-combustion and supplementary fuel potentials, presents the process engineering of co-combustion, and examines the obstacles encountered during the technical conversion, the environmental questions, and the potential for co-combustion of the above materials in existing power stations. The electrical power sector is subject to strong changes due to the liberalisation of the energy market. The pressure on costs has increased and the periods available for planning are shorter. On the one hand, this arouses an increased interest in co-combustion of waste materials because of possible additional payments for the wastes. On the other hand, however, initiatives in this respect are counteracted by high investments costs necessary for the introduction of co-combustion with the existing high environmental standards. What is more, the competitive situation reduces the exchange of experience between the power station operators. Co-combustion of sewage

  8. A study on development of controller and 3-D visulaization for sludge lancing of nuclear power steam generator

    International Nuclear Information System (INIS)

    Kim, J. H.; Jo, B. H.

    2001-01-01

    A visualization tool for representing robot task of sludge lancing in 3-D, and control system for sludge lancing robot is developed. This tool is developed utilizing MS DirectX, and graphic models for this tool is drawn through 3ds max 3.0. On robot controller, we split it in two part. We set the minimum part of controller into CV, and the remaining part out of CV. So we can use the work space efficiently and simplify the decontamination process. Because this tool is developed as module type, One can develop a controller set with another program, and can easily apply it to the other field

  9. Co-combustion and gasification of various biomasses

    Energy Technology Data Exchange (ETDEWEB)

    Mutanen, K. [A. Ahlstrom Corporation, Varkaus (Finland). Ahlstrom Pyropower

    1996-12-31

    During the last twenty years the development of fluidized bed combustion and gasification technology has made it possible to increase significantly utilisation of various biomasses in power and heat generation. The forerunner was the pulp and paper industry that has an adequate biomass fuel supply and energy demand on site. Later on municipalities and even utilities have seen biomass as a potential fuel. The range of available biomasses includes wood-based fuels and wastes like bark, wood chips, and saw dust, agricultural wastes like straw, olive waste and rice husk, sludges from paper mills and de-inking plants, other wastes like municipal sludges, waste paper and RDF. Recently new environmental regulations and taxation of fossil fuels have further increased interest in the use of biomasses in energy generation. However, in many cases available quantities and/or qualities of biomasses are not adequate for only biomass-based energy generation in an economic sense. On the other hand plant owners want to maintain a high level of fuel flexibility and fuel supply security. In some cases disposing by burning is the only feasible way to handle certain wastes. In many cases the only way to fulfil these targets and utilize the energy is to apply co-combustion or gasification of different fuels and wastes. Due to the fact that fluidized bed combustion technology offers a very high fuel flexibility and high combustion efficiency with low emissions it has become the dominating technology in co-combustion applications. This presentation will present Alhstrom`s experiences in co-combustion of biomasses in bubbling beds and Ahlstrom Pyroflow circulating fluidized beds based on about 200 operating references worldwide. CFB gasification will also be discussed 9 refs.

  10. Acceleration of organic removal and electricity generation from dewatered oily sludge in a bioelectrochemical system by rhamnolipid addition.

    Science.gov (United States)

    Zhang, Yunshu; Zhao, Qingliang; Jiang, Junqiu; Wang, Kun; Wei, Liangliang; Ding, Jing; Yu, Hang

    2017-11-01

    Conversion of biomass energy of dewatered oily sludge to electricity is the rate-limiting process in bioelectrochemical system (BES). In this study, 2mgg -1 rhamnolipids were added to dewatered oily sludge, resulting in a significant enhancement in maximum power density from 3.84±0.37 to 8.63±0.81Wm -3 , together with an increase in total organic carbon (TOC) and total petroleum hydrocarbon (TPH) removal from 24.52±4.30 to 36.15±2.79mgg -1 and 29.51±3.30 to 39.80±2.47mgg -1 , respectively. Rhamnolipids can also enhance the solubilization and promote the hydrolysis of dewatered oily sludge with increases in SOCD from 14.93±2.44 to 18.40±0.08mgg -1 and VFAs from 1.02±0.07 to 1.39±0.12mgg -1 . Furthermore, bacteria related to substrate degradation were predominant in dewatered oily sludge, and bacteria related to the sulfate/sulfide cycle were significantly enriched by rhamnolipid addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Combustion physics

    Science.gov (United States)

    Jones, A. R.

    1985-11-01

    Over 90% of our energy comes from combustion. By the year 2000 the figure will still be 80%, even allowing for nuclear and alternative energy sources. There are many familiar examples of combustion use, both domestic and industrial. These range from the Bunsen burner to large flares, from small combustion chambers, such as those in car engines, to industrial furnaces for steel manufacture or the generation of megawatts of electricity. There are also fires and explosions. The bountiful energy release from combustion, however, brings its problems, prominent among which are diminishing fuel resources and pollution. Combustion science is directed towards finding ways of improving efficiency and reducing pollution. One may ask, since combustion is a chemical reaction, why physics is involved: the answer is in three parts. First, chemicals cannot react unless they come together. In most flames the fuel and air are initially separate. The chemical reaction in the gas phase is very fast compared with the rate of mixing. Thus, once the fuel and air are mixed the reaction can be considered to occur instantaneously and fluid mechanics limits the rate of burning. Secondly, thermodynamics and heat transfer determine the thermal properties of the combustion products. Heat transfer also plays a role by preheating the reactants and is essential to extracting useful work. Fluid mechanics is relevant if work is to be performed directly, as in a turbine. Finally, physical methods, including electric probes, acoustics, optics, spectroscopy and pyrometry, are used to examine flames. The article is concerned mainly with how physics is used to improve the efficiency of combustion.

  12. On the formulation and assessment of flamelet-generated manifolds applied to two-phase turbulent combustion

    Science.gov (United States)

    Bojko, Brian T.

    Accounting for the effects of finite rate chemistry in reacting flows is intractable when considering the number of species and reactions to be solved for during a large scale flow simulation. This is especially complicated when solid/liquid fuels are also considered. While modeling the reacting boundary layer with the use of finite-rate chemistry may allow for a highly accurate description of the coupling between the flame and fuel surface, it is not tractable in large scale simulations when considering detailed chemical kinetics. It is the goal of this research to investigate a Flamelet-Generated Manifold (FGM) method in order to reduce the finite rate chemistry to a lookup table cataloged by progress variables and queried during runtime. In this study, simplified unsteady 1D flames with mass blowing are considered for a solid biomass fuel where the FGM method is employed as a model reduction strategy for potential application to multidimensional calculations. Two types of FGM are considered. The first are a set of steady-state flames differentiated by their scalar dissipation rate. Results show the use of steady flames produce unacceptable errors compared to the finite-rate chemistry solution, with temperature errors in excess of 45%. To avoid these errors, a new methodology for developing an unsteady FGM (UFGM) is presented that accounts for unsteady diffusion effects and greatly reduces errors in temperature with differences that are under 10%. The FGM modeling is then extended to individual droplet combustion with the development of a Droplet Flamelet-Generated Manifold (DFGM) to account for the effects of finite-rate chemistry of individual droplets. A spherically symmetric droplet model is developed for methanol and aluminum. The inclusion of finite-rate chemistry allows the capturing of the transition from diffusion to kinetically controlled combustion as the droplet diameter decreases. The droplet model is then used to create a DFGM by successively

  13. Combustion generated noise in gas turbine combustors. [engine noise/noise reduction

    Science.gov (United States)

    Strahle, W. C.; Shivashankara, B. N.

    1974-01-01

    Experiments were conducted to determine the noise power and spectra emitted from a gas turbine combustor can exhausting to the atmosphere. Limited hot wire measurements were made of the cold flow turbulence level and spectra within the can. The fuels used were JP-4, acetone and methyl alcohol burning with air at atmospheric pressure. The experimental results show that for a fixed fuel the noise output is dominated by the airflow rate and not the fuel/air ratio. The spectra are dominated by the spectra of the cold flow turbulence spectra which were invariant with airflow rate in the experiments. The effect of fuel type on the noise power output was primarily through the heat of combustion and not the reactivity. A theory of combustion noise based upon the flame radiating to open surroundings is able to reasonably explain the observed results. A thermoacoustic efficiency for noise radiation as high as .00003 was observed in this program for JP-4 fuel. Scaling rules are presented for installed configurations.

  14. Sewage sludge conditioning with the application of ash from biomass-fired power plant

    Science.gov (United States)

    Wójcik, Marta; Stachowicz, Feliks; Masłoń, Adam

    2018-02-01

    During biomass combustion, there are formed combustion products. Available data indicates that only 29.1 % of biomass ashes were recycled in Poland in 2013. Chemical composition and sorptive properties of ashes enable their application in the sewage sludge treatment. This paper analyses the impact of ashes from biomass-combustion power plant on sewage sludge dewatering and higienisation. The results obtained in laboratory tests proved the possitive impact of biomass ashes on sewage sludge hydration reduction after dewatering and the increase of filtrate volume. After sludge conditioning with the use of biomass combustion by-products, the final moisture content decreased by approximatelly 10÷25 % in comparison with raw sewage sludge depending on the method of dewatering. The application of biomass combustion products in sewage sludge management could provide an alternative method of their utilization according to law and environmental requirements.

  15. Co-pelletization of sewage sludge and agricultural wastes.

    Science.gov (United States)

    Yilmaz, Ersel; Wzorek, Małgorzata; Akçay, Selin

    2017-09-21

    This paper concerns the process of production and properties of pellets based on biomass wastes. Co-pelletization was performed for sewage sludge from municipal wastewater treatment plant and other biomass material such as animal and olive wastes. The aim of the present study was to identify the key factors affecting on the sewage sludge and agricultural residues co-pelletization processes conditions. The impact of raw material type, pellet length, moisture content and particle size on the physical properties was investigated. The technic and technological aspects of co-pelletization were discussed in detail. The physical parameters of pellets, i.e.: drop strength, absorbability and water resistance were determined. Among others, also energy parameters: low and high heat value, content of ash and volatiles were presented. Results showed the range of raw materials moisture, which is necessary to obtain good quality biofuels and also ratio of sewage sludge in pelletizing materials. The analysis of the energetic properties has indicated that the pellet generated on the basis of the sewage sludge and another biomass materials can be applied in the processes of co-combustion with coal. Those biofuels are characterised with properties making them suitable for use in thermal processes and enabling their transport and storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Combustion, performance and emissions of a diesel power generator fueled with biodiesel-kerosene and biodiesel-kerosene-diesel blends

    International Nuclear Information System (INIS)

    Bayındır, Hasan; Işık, Mehmet Zerrakki; Argunhan, Zeki; Yücel, Halit Lütfü; Aydın, Hüseyin

    2017-01-01

    High percentages of biodiesel blends or neat biodiesel cannot be used in diesel engines due to high density and viscosity, and poor atomization properties that lead to some engine operational problems. Biodiesel was produced from canola oil by transesterification process. Test fuels were prepared by blending 80% of the biodiesel with 20% of kerosene (B80&K20) and 80% of the biodiesel with 10% of kerosene and 10% diesel fuel (B80&K10&D10). Fuels were used in a 4 cylinders diesel engine that was loaded with a generator. Combustion, performance and emission characteristics of the blend fuels and D2 in the diesel engine for certain loads of 3.6, 7.2 and 10.8 kW output power and 1500 rpm constant engine speed were experimented and deeply analyzed. It was found that kerosene contained blends had quite similar combustion characteristics with those of D2. Mass fuel consumption and Bscf were slightly increased for blend fuels. HC emissions slightly increased while NOx emissions considerably reduced for blends. It was resulted that high percentages of biodiesel can be a potential substitute for diesel fuel provided that it is used as blending fuel with certain amounts of kerosene. - Highlights: • Effects of kerosene and diesel addition to biodiesel in a diesel engine were investigated. • B80&K10 and B80&K10&D10 were tested and comparisons have been made with D2. • Similar fuel properties and combustion parameters have been found for all fuels. • Heat release initiated earlier for B80&K10 and B80&K10&D10. • CO and NOx emissions are lowered for B80&K10 and B80&K10&D10.

  17. Accounting Methodology for Source Energy of Non-Combustible Renewable Electricity Generation

    Energy Technology Data Exchange (ETDEWEB)

    Donohoo-Vallett, Paul [US Department of Energy, Washington, DC (United States)

    2016-10-01

    As non-combustible sources of renewable power (wind, solar, hydro, and geothermal) do not consume fuel, the “source” (or “primary”) energy from these sources cannot be accounted for in the same manner as it is for fossil fuel sources. The methodology chosen for these technologies is important as it affects the perception of the relative size of renewable source energy to fossil energy, affects estimates of source-based building energy use, and overall source energy based metrics such as energy productivity. This memo reviews the methodological choices, outlines implications of each choice, summarizes responses to a request for information on this topic, and presents guiding principles for the U.S. Department of Energy, (DOE) Office of Energy Efficiency and Renewable Energy (EERE) to use to determine where modifying the current renewable source energy accounting method used in EERE products and analyses would be appropriate to address the issues raised above.

  18. MHD Electrical Power Generation in Result of Hydrogen/Oxygen Combustion

    National Research Council Canada - National Science Library

    Bityurin, V. A; Bocharov, A. N; Krasilnikov, A. V; Mikhailov, A. V

    2003-01-01

    .... To increase the electron concentration a seed injector system is used. The goal of this study is the physical demonstration of the MMD electrical power generation under conditions simulating those for on-board multi-megawatt power generating system...

  19. Effects of methyl group on aromatic hydrocarbons on the nanostructures and oxidative reactivity of combustion-generated soot

    KAUST Repository

    Guerrero Peña, Gerardo D.J.

    2016-07-23

    The substituted and unsubstituted aromatic hydrocarbons, present in transportation fuels such as gasoline and diesel, are thought to be responsible for most of the soot particles produced during their combustion. However, the effects of the substituted alkyl groups on the aromatic hydrocarbons on their sooting tendencies, and on the physical and chemical properties of soot produced from them are not well understood. In this work, the effect of the presence of methyl groups on aromatic hydrocarbons on their sooting propensity, and on the oxidative reactivity, morphology, and chemical composition of soot generated from them in diffusion flames is studied using benzene, toluene, and m-xylene as fuels. Several experimental techniques including high resolution transmission electron microscopy and X-ray diffraction are used to identify the morphological changes in soot, whereas the elemental and thermo-gravimetric analyses, electron energy loss spectroscopy, and Fourier transform infrared spectroscopy are used to study the changes in its chemical properties and reactivity. The activation energies for soot oxidation are calculated at different conversion levels, and a trend in the reactivity of soots from benzene, toluene and m-xylene is reported. It is observed that the sizes of primary particles and graphene-like sheets, and the concentrations of aliphatics and oxygenated groups in soot particles decreased with the addition of methyl group(s) on the aromatic ring. The physicochemical changes in soot are found to support the oxidative reactivity trends. © 2016 The Combustion Institute

  20. Generation of dissolved organic matter and byproducts from activated sludge during contact with sodium hypochlorite and its implications to on-line chemical cleaning in MBR.

    Science.gov (United States)

    Cai, Weiwei; Liu, Jiaqi; Zhang, Xiangru; Ng, Wun Jern; Liu, Yu

    2016-11-01

    On-line chemical cleaning of membranes with sodium hypochlorite (NaClO) has been commonly employed for maintaining a constant permeability of membrane bioreactor (MBR) due to its simple and efficient operation. However, activated sludge is inevitably exposed to NaClO during this cleaning process. In spite of the broad applications of on-line chemical cleaning in MBR such as chemical cleaning-in-place (CIP) and chemical enhanced backwash (CEB), little information is currently available for the release of emerging dissolved organic matter (DOM) and byproducts from this prevalent practice. Therefore, in this study, activated sludge suspended in a phosphate buffered saline solution was exposed to different doses of NaClO in order to determine the generation of potential DOM and byproducts. The results showed the occurrence of significant DOM release (up to 24.7 mg/L as dissolved organic carbon) after exposure to NaClO for 30 min. The dominant components of the released DOM were characterized to be humic acid-like as well as protein-like substances by using an excitation-emission matrix fluorescence spectrophotometer. Furthermore, after the contact of activated sludge with NaClO, 19 kinds of chlorinated and brominated byproducts were identified by ultra performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry, eight of which were confirmed and characterized with standard compounds. Many byproducts were found to be halogenated aromatic compounds, including halopyrroles and halo(hydro)benzoquinones, which had been reported to be significantly more toxic than the halogenated aliphatic ones. Consequently, this study offers new insights into the practice of on-line chemical cleaning, and opens up a window to re-examine the current operation of MBR by looking into the generation of micropollutants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Fractionation and business potential from sludge - Pafrak

    Energy Technology Data Exchange (ETDEWEB)

    Kylloenen, H.; Groenroos, A.; Pirkonen, P. (VTT Tecchnical Research Centre of Finland, Jyvaeskylae (Finland)), Email: hanna.kyllonen@vtt.fi; Maekinen, L.; Aemmaelae, A.; Niinimaeki, J. (Univ. of Oulu (Finland)), Email: liisa.makinen@oulu.fi

    2010-10-15

    Wastewater sludges contain valuable components which can be recycled and converted to secondary raw material. High water content of sludge can hinder the further processing. Dry solids content of waste activated sludge after dewatering can be as low as 12-20% and even lower for tertiary sludge. This research aimed with better knowledge of sludge and fractionation to generate potential business ideas, which could lead to new sludge based products and services in national and international markets already in this project or in separate development projects. Primary, waste activated, tertiary and deinking sludge from pulp and paper industry and municipal waste activated sludge were the suspensions to be studied. Basic properties of these sludges have been determined by large number of analysing methods. Wood based components and chemical elements have been determined to clarify the raw material potential for biorefineries. Conventional fractionation techniques (decanter centrifuge, hydrocyclone, belt filter press and sieve bend) have been used to see how the sludge can be fractionated. Correlations of wood based components and dewatering properties have been studied especially for the waste activated sludge. The effects of wood based filter aids were studied on the dewatering properties of waste activated sludge. State of the art has been drawn up about the current utilisation of wastewater sludge. (orig.)

  2. Radiation hygienization of raw sewage sludge

    International Nuclear Information System (INIS)

    Shah, M.R.; Lavale, D.S.; Rawat, P.; Benny, P.G.; Sharma, A.K.; Dey, G.R.; Bhave, V.

    2001-01-01

    'Radiation treatment of municipal sewage sludge can achieve resource conservation and recovery objectives. The liquid sludge irradiator of Sludge Hygienization Research Irradiator at Baroda (India) was operated for generating data on treatment of raw sludge containing 3-4 % solids. The plant system was modified for irradiating raw sludge without affecting basic irradiator initially designed to treat digested sludge. Hourly samples were analysed for estimation of disinfection dose requirement. Sand separated from the sludge was used as in-situ dosimeter by making use of its thermoluminescence property. Investigations are being carried out for regrowth of Total Coliforms in the sludge samples from this irradiator. Possibility of inadequate treatment due to geometric configuration of irradiator is being checked. (author)

  3. Theoretical methane production generated by the co-digestion of organic fraction municipal solid waste and biological sludge

    Directory of Open Access Journals (Sweden)

    A. Nielfa

    2015-03-01

    Full Text Available The co-digestion of two problematic and available wastes, namely Organic Fraction Municipal Solid Waste (OFMSW and biological sludge, was carried out in this work. Biochemical Methane Potential (BMP tests are a useful tool for determining the best substrate and co-digestion configurations, however there are some methodologies destined to save costs and time from this process by using the theoretical final methane potential of a substrate from its organic composition. Besides there are some models capable not only of reproducing the methane curve behavior, but also of predicting final methane productions from the first days of experimentation. Methodologies based in the elemental composition for the determination of theoretical production fit better with the experimental results and behavior, nevertheless the Gompertz model was capable of predicting the final productivity within the 7th day of experiment, selecting at the same time the co-digestion of 80% OFMSW and 20% Biological sludge as the optimum.

  4. [Performance of Electricity Generation and Feasibility of Discontinuous Power Supply of MFC by Using Pretreated Excess Sludge as Fuel].

    Science.gov (United States)

    Zhao, Yan-hui; Zhao, Yang-guo; Guo, Liang

    2016-03-15

    The feasibility of treating pretreated excess sludge and capacity of supplying continuous power of microbial fuel cells (MFCs) were investigated. Two-chamber microbial fuel cells were started up and operated by using thermal pretreated excess sludge as the substrate. Potential fluctuations were achieved by changing the cathode electron acceptor. During the changes of electron acceptor, the operational stability of MFCs was assessed. The results indicated that the MFCs started successfully with oxygen as the cathode electron acceptor and reached 0.24 V after 148 hours. When the cathode electron acceptor was replaced by potassium ferricyanide, MFCs could obtain the maximum output voltage and maximum power density of 0.66 V and 4.21 W · m⁻³, respectively. When the cathode electron acceptor was changed from oxygen to potassium ferricyanide or the MFCs were closed circuit, the output power of MFCs recovered rapidly. In addition, changes of electron acceptor showed no effect on the removal of COD and ammonia nitrogen. Their removal efficiencies approached to 70% and 80%, respectively. This study concluded that MFC could treat the pretreated excess sludge and produce electricity simultaneously with a high power density. The MFC could also achieve discontinuous electricity supply during operation.

  5. Prediction of combustible waste generation and estimate of potential energy by applying waste to energy technologies in Korea

    International Nuclear Information System (INIS)

    Lee, Jang-Soo; Cho, Sung-Jin; Jung, Hae-Young; Lee, Ki-Bae; Seo, Yong-Chil

    2010-01-01

    In 2007 total waste generation rate in Korea was 318,670 ton,day. In general waste generation rate shows rising trend since 2000. Wastes are composed of municipal waste 14.9 % industrial waste 34.1 % and construction waste 51.0 %. Treatment of wastes by recycling was 81.1 % landfill 11.1 % incineration 5.3 % and ocean dumping 2.4 %. National waste energy policies have been influenced by various factors such as environmental problem economy technology level (could be made energy), and so on. Korea has the worlds third dense population density environmental pollution load per unit land area is the highest in OECD countries caused due to the fast development in economy, industrialization and urbanization in recent. Also, land area per person is just 2,072 m 2 . Landfill capacity reaches the upper limit, industrial waste generation is increasing. Searching new-renewable energy is vital to substitute fossil fuel considering its increasing price. Korea is the world's 10th biggest energy consuming country and 97% of energy depends on importing. Korea aims to increases supply of new-renewable energy by 5% until the 2011. In this study, we computed the amount of combustible waste from municipality generated by the multiple regression analysis. The existing technologies for converting waste to energy were surveyed and the technologies under development or utilizing in future were also investigated. Based on the technology utilization, the amount of energy using waste to energy technology could be estimated in future. (author)

  6. Biofuels Combustion

    Science.gov (United States)

    Westbrook, Charles K.

    2013-04-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

  7. Biofuels combustion.

    Science.gov (United States)

    Westbrook, Charles K

    2013-01-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

  8. Fabrication and processing of next-generation oxygen carrier materials for chemical looping combustion

    Energy Technology Data Exchange (ETDEWEB)

    Nadarajah, Arunan [Univ. of Toledo, OH (United States)

    2017-04-26

    Among numerous methods of controlling the global warming effect, Chemical Looping Combustion is known to be the most viable option currently. A key factor to a successful chemical looping process is the presence of highly effective oxygen carriers that enable fuel combustion by going through oxidation and reduction in the presence of air and fuel respectively. In this study, CaMnO3-δ was used as the base material and doped on the A-site (Sr or La) and B-site (Fe, Ti, Zn and Al) by 10 mol % of dopants. Solid state reaction followed by mechanical extrusion (optimized paste formula) was used as the preparation method A series of novel doped perovskite-type oxygen carrier particles (CaxLa (Or Sa)1-x Mn1-yByO3-δ (B-site = Fe, Ti, Al, or Zr)) were synthesized by the proposed extrusion formula. The produced samples were characterized with XRD, SEM, BET and TGA techniques. According to the results obtained from TGA analysis, the oxygen capacity of the samples ranged between 1.2 for CLMZ and 1.75 for CSMF. Reactivity and oxygen uncoupling behaviors of the prepared samples were also evaluated using a fluidized bed chemical looping reactor using methane as the fuel at four different temperatures (800, 850, 900, 950 °C). All of the oxygen carriers showed oxygen uncoupling behavior and they were able to capture and release oxygen. Mass-based conversion of the perovskites was calculated and temperature increase proved to increase the mass-based conversion rate in all of the samples under study. Gas yield was calculated at 950 °C as well, and results showed that CLMZ, CM and CSMF showed 100% gas yields and CLMF and CSMZ showed approximately 85% yield in fluidized bed reactor, which is a high and acceptable quantity. Based on extended reactor tests the modified calcium manganese perovskite structures (CSMF) can be a good candidate for future pilot tests.

  9. Effects of volatile coatings on the morphology and optical detection of combustion-generated black carbon particles.

    Energy Technology Data Exchange (ETDEWEB)

    Bambha, Ray.; Dansson, Mark A; Schrader, Paul E.; Michelsen, Hope A.

    2013-09-01

    We have measured time-resolved laser-induced incandescence (LII) from combustion-generated mature soot extracted from a burner and (1) coated with oleic acid or (2) coated with oleic acid and then thermally denuded using a thermodenuder. The soot samples were size selected using a differential mobility analyser and characterized with a scanning mobility particle sizer, centrifugal particle mass analyser, and transmission electron microscope. The results demonstrate a strong influence of coatings particle morphology and on the magnitude and temporal evolution of the LII signal. For coated particles higher laser fluences are required to reach LII signal levels comparable to those of uncoated particles. This effect is predominantly attributable to the additional energy needed to vaporize the coating while heating the particle. LII signals are higher and signal decay rates are significantly slower for thermally denuded particles relative to coated or uncoated particles, particularly at low and intermediate laser fluences.

  10. A method for generating reduced-order combustion mechanisms that satisfy the differential entropy inequality

    Science.gov (United States)

    Ream, Allen E.; Slattery, John C.; Cizmas, Paul G. A.

    2018-04-01

    This paper presents a new method for determining the Arrhenius parameters of a reduced chemical mechanism such that it satisfies the second law of thermodynamics. The strategy is to approximate the progress of each reaction in the reduced mechanism from the species production rates of a detailed mechanism by using a linear least squares method. A series of non-linear least squares curve fittings are then carried out to find the optimal Arrhenius parameters for each reaction. At this step, the molar rates of production are written such that they comply with a theorem that provides the sufficient conditions for satisfying the second law of thermodynamics. This methodology was used to modify the Arrhenius parameters for the Westbrook and Dryer two-step mechanism and the Peters and Williams three-step mechanism for methane combustion. Both optimized mechanisms showed good agreement with the detailed mechanism for species mole fractions and production rates of most major species. Both optimized mechanisms showed significant improvement over previous mechanisms in minor species production rate prediction. Both optimized mechanisms produced no violations of the second law of thermodynamics.

  11. Anaerobic digestion of industrial activated aerobic sludge

    International Nuclear Information System (INIS)

    Goodloe, J.G.; Roberts, R.S.

    1990-04-01

    The Tennessee Eastman Company manufactures a variety of organic chemicals, plastics and fibers at their Kingsport Tennessee Facility. The wastewater generated during the manufacture of these compounds is currently treated using an activated sludge process. The objective of the project is to evaluate the economic potential of an anaerobic digestion process to convert industrial sludge at the Tennessee Eastman Company into biogas. The evaluation will require collection and analysis of experimental data on the anaerobic digestion of industrial sludge obtained from Kingsport. Although the experiments will be conducted using Tennessee Eastman sludge, these results should be also generally applicable to similar industrial sludge

  12. Electrodialysis Treatment of Industrial Waste Waters That Generaters Little Sludge; Tratamiento de aguas residuales industriales por electrodialisis, tecnica que genera pocos lodos

    Energy Technology Data Exchange (ETDEWEB)

    Savastoma Mariel, C. [Universidad de Cantabria. Santander (Spain)

    2002-07-01

    Electrodialysis with bipolar membranes is reviewed as a separation technique and details are shown. The method is used in several process applications but its adoption looks particularly attractive in the treatment of waste water streams consisting primarily of diluted residual salts and electrolytes. It is argued that the main advantage shown by the technology compared to the classical treatment consisting of adding lime to neutralize the waste waters resides in tis avoiding the generation of voluminous sludges thus permitting savings in the management and disposal of the mud. Other interesting applications are those operations where generating acidity and/or alkalinity with addition of no extra chemicals is desirable, such as the regeneration of ion exchange resins. (Author) 34 refs.

  13. Turbulent combustion

    Energy Technology Data Exchange (ETDEWEB)

    Talbot, L.; Cheng, R.K. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    Turbulent combustion is the dominant process in heat and power generating systems. Its most significant aspect is to enhance the burning rate and volumetric power density. Turbulent mixing, however, also influences the chemical rates and has a direct effect on the formation of pollutants, flame ignition and extinction. Therefore, research and development of modern combustion systems for power generation, waste incineration and material synthesis must rely on a fundamental understanding of the physical effect of turbulence on combustion to develop theoretical models that can be used as design tools. The overall objective of this program is to investigate, primarily experimentally, the interaction and coupling between turbulence and combustion. These processes are complex and are characterized by scalar and velocity fluctuations with time and length scales spanning several orders of magnitude. They are also influenced by the so-called {open_quotes}field{close_quotes} effects associated with the characteristics of the flow and burner geometries. The authors` approach is to gain a fundamental understanding by investigating idealized laboratory flames. Laboratory flames are amenable to detailed interrogation by laser diagnostics and their flow geometries are chosen to simplify numerical modeling and simulations and to facilitate comparison between experiments and theory.

  14. 78 FR 34918 - Direct Final Approval of Sewage Sludge Incinerators State Plan for Designated Facilities and...

    Science.gov (United States)

    2013-06-11

    ... Approval of Sewage Sludge Incinerators State Plan for Designated Facilities and Pollutants; Indiana AGENCY... to control air pollutants from ``Sewage Sludge Incinerators'' (SSI). The Indiana Department of... unit,'' in part, as any device that combusts sewage sludge for the purpose of reducing the volume of...

  15. Impact of feedstock properties and operating conditions on sewage sludge gasification in a fixed bed gasifier.

    Science.gov (United States)

    Werle, Sebastian

    2014-10-01

    This work presents results of experimental studies on the gasification process of granulated sewage sludge in a laboratory fixed bed gasifier. Nowadays, there is a large and pressing need for the development of thermal methods for sewage sludge disposal. Gasification is an example of thermal method that has several advantages over the traditional combustion. Gasification leads to a combustible gas, which can be used for the generation of useful forms of final energy. It can also be used in processes, such as the drying of sewage sludge directly in waste treatment plant. In the present work, the operating parameters were varied over a wide range. Parameters, such as air ratio λ = 0.12 to 0.27 and the temperature of air preheating t = 50 °C to 250 °C, were found to influence temperature distribution and syngas properties. The results indicate that the syngas heating value decreases with rising air ratio for all analysed cases: i.e. for both cold and preheated air. The increase in the concentration of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Preheating of the gasification agent supports the endothermic gasification and increases hydrogen and carbon monoxide production. © The Author(s) 2014.

  16. Communal sewage sludge treatement against the background of the new European Sewage Sludge Treatment Regulations; Kommunale Klaerschlammbehandlung vor dem Hintergrund der neuen Europaeischen Klaerschlammrichtlinien

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The following issues were discussed at the Darmstadt conference: The European Sewage Sludge Treatment Regulation, hygienisation of sewage sludge, waste water purification without excess sludge production, stabilisation of sewage sludge, dewatering and disposal by combustion or utilisation as an agricultural fertilizer. [German] Themen des Darmstaedter Seminars Abwassertechnik waren: Europaeische Klaerschlammrichtlinie, Klaerschlammhygienisierung, Abwasserreinigung ohne Anfall von Ueberschussschlamm, Klaerschlammstabilisierung, Entwaesserung und Entsorgung durch Verbrennung oder in der Landwirtschaft. (UKE)

  17. Synthesis of lithium silicates generators of tritium by a modified method of combustion; Sintesis de silicatos de litio generadores de tritio por un metodo modificado de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Cruz G, D

    2003-07-01

    The ceramics of lithium have been proposed as generating materials of tritium through the following reaction: {sup 6} Li + {sup 1} n {yields} {sup 4} He + {sup 3} H . In previous works carried out by Pfeiffer and collaborators, the lithium silicates generators of tritium were prepared using the following methods: reactions of solid state, precipitation and sol-gel synthesis. Although those methods have advantages, it is required of heating at high temperatures (900 C during four hours) to be able to obtain the crystalline compounds. Those products found in these works were diverse crystallization forms of the lithium silicates and of SiO{sub 2}, such as, Li{sub 2}SiO{sub 3}, Li{sub 2}Si{sub 2}0{sub 5}, Li{sub 4}SiO{sub 4}, and quartz (SiO{sub 2}). The combustion method uses exothermic reactions to take place ceramic compounds. The precursor solutions are mixtures of the nitrate of metal oxidizer and the fuels (urea, glycine, carbohydrazide). However the reported method in the literature, it is not useful to prepare lithium silicates, for what was modified using non oxidizers compounds. The lithium hydroxide (LiOH) and the silicic acid (H{sub 2}SiO{sub 3}) they were the compounds non oxidizers used, and the urea (CH{sub 4}N{sub 2}O) it was the one fuel. They were carried out two series of experiments; inside the series 1 of experiments are varied the molar ratio of lithium hydroxide and urea (LiOH : H{sub 2}SiO{sub 3} = 1, 2 and 3, LiOH : CH{sub 4}N{sub 2}O = 1, 2, 3, 4 and 5) and the prepared mixtures were taken to one muffle previously preheated to a temperature of 450 C during 5 minutes. In the series 2 of experiments was studied the effect of the temperature and of the washed with distilled water in the prepared samples with the following molar ratios: LiOH : H{sub 2}SiO{sub 3} : CH{sub 4}N{sub 2}O = 1:1:3, 2:1:3, 3:1:3 and 3:1:6, those which were heated to temperatures from 450 C up to 750 C and were washed. The obtained samples were characterized by X

  18. Fractionation and business potential from sludge (Pafrak)

    Energy Technology Data Exchange (ETDEWEB)

    Pirkonen, P.; Kylloenen, H. (VTT Technical Research Centre of Finland, Jyvaeskylae (Finland)); Niinimaeki, J.; Oksanen, J. (Univ. of Oulu (Finland))

    2008-07-01

    Wastewater sludge contains valuable components which can be recycled and converted to secondary raw material. High water content of sludge can hinder the further processing. Dry solids content of waste activated sludge after dewatering can be as low as 12-20% and even lower for tertiary sludge. This research aims with better knowledge of sludge and fractionation to generation of potential business ideas which could lead to new sludge based products and services in national and international markets already in this project or in separate development projects. Municipal waste activated sludge and deinking, primary, waste activated and tertiary sludge from pulp and paper industry are the suspensions to be studied. Basic properties of these sludges have been determined by large number of analysing methods. Dewatering properties, which are one of the key topics, have been studied with a novel flocculation/filtration device. Conventional fractionation equipment (decanter centrifuge, hydrocyclone. filter belt press and sieve bend) have been used to see how the sludge could be fractionated. State of the art has been drawn up about the current utilisation of wastewater sludge. One of the key issues in future research is how to affect the binding forces between different substances in sludge. (orig.)

  19. Integrated bioconversion of pulp and paper primary sludge to second generation bioethanol using Saccharomyces cerevisiae ATCC 26602.

    Science.gov (United States)

    Mendes, Cátia V T; Cruz, Crispin H G; Reis, Diana F N; Carvalho, M Graça V S; Rocha, Jorge M S

    2016-11-01

    Primary sludge, from different pulp and paper mills, was used as feedstock in simultaneous saccharification and fermentation (SSF) processes to produce ethanol. SSF was carried out with Saccharomyces cerevisiae ATCC 26602 yeast and NS 22192 enzymatic extract using 150gL(-1) of carbohydrates (CH) from primary sludge. The effect of sterilization, reduction of enzyme dosage and fed-batch vs. batch conditions were studied. The removal of sterilization can be considered since no contamination or atypical by-products were observed, although SSF efficiency slightly decreased. The reduction of the enzyme dosage from 35 to 15FPUgCH(-1) was successful. Despite of initial mixing difficulties, batch SSF enabled higher ethanol concentration (41.7gL(-1)), conversion yield (48.9%) and productivity (0.78gL(-1)h(-1)), compared to the fed-batch process at the same conditions of low enzyme dosage of 5FPUgCH(-1) and high solids content of 21.7%, rarely found in literature. Published by Elsevier Ltd.

  20. Simulation and analysis of the tangential flow in the combustion chamber of a steam generator; Simulacion y analisis del flujo tangencial en la camara de combustion de un generador de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Ramirez, Isaias

    1997-06-01

    The present thesis work describes the simulation and analysis of the combustion chamber of a steam generator VU-60 of the tangential type, which is based on the solution of the generalized equation of transport, using mathematical models developed for the characterization of physical phenomena to close the governing equations systems. For the solution of the mathematical models and governing equations the method of finite volume was used, which is based on the concept of control volume. A three-dimensional computational model was developed by means of which the velocity, pressure, and temperature profiles were considered and species in steady state in time for the combustion chamber and fuel supplying ducts for an existing design of a steam generator. The model provides information related to the behavior of the connected variables and that are of interest in the design and manufacture of steam generators of the tangential type. Turbulence and combustion models were used for the estimation of the velocity and pressure profiles for the case of the equation of momentum and temperature for the case of the energy equation. The radiation model was not connected to the system of governing equations due to limitations in the memory of the computer used for the simulation of these phenomena. The computational model was developed in a workstation Risc System/6000 and by means of the Code of computational dynamics of fluids Star-CD. 5390 cells and 43350 vertexes constitute the model. With this model information is generated to support the designer of the steam generators in the decision making during the design and the manufacture of the combustion chambers of the steam generators of high performance of the tangential type similar to the one analyzed in this thesis work. The results obtained of the present thesis are: The flow patterns of the combustion gases inside the combustion chamber of the steam generator, as well as the velocity profiles of the oxidant in the

  1. Power generation and gaseous emissions performance of an internal combustion engine fed with blends of soybean and beef tallow biodiesel.

    Science.gov (United States)

    Schirmer, Waldir Nagel; Gauer, Mayara Ananda; Tomaz, Edson; Rodrigues, Paulo Rogério Pinto; de Souza, Samuel Nelson Melegari; Chaves, Luiz Inácio; Villetti, Lucas; Olanyk, Luciano Zart; Cabral, Alexandre Rodrigues

    2016-01-01

    This study aimed to compare the performance of an internal combustion engine fed with blends of biodiesel produced from soybean and diesel, and blends of biodiesel produced from beef tallow and diesel. Performance was evaluated in terms of power generated at low loading conditions (0.5, 1.0 and 1.5 kW) and emission of organic and inorganic pollutants. In order to analyse inorganic gases (CO, SO2 and NOx), an automatic analyser was used and the organic emissions (benzene, toluene, ethylbenzene and xylene - BTEX) were carried out using a gas chromatograph. The results indicate that the introduction of the two biodiesels in the fuel caused a reduction in CO, SO2 and BTEX emissions. In addition, the reduction was proportional to the increase in loading regime. Beef tallow biodiesels presented better results regarding emission than soybean biodiesels. The use of pure biodiesels also presented a net reduction in pollutant gas emissions without hindering the engine generator performance.

  2. Combustion of PTFE: The Effects of Gravity and Pigmentation on Ultrafine Particle Generation

    Science.gov (United States)

    McKinnon, J. Thomas; Srivastava, Rajiv; Todd, Paul

    1997-01-01

    Ultrafine particles generated during polymer thermodegradation are a major health hazard, owing to their unique pathway of processing in the lung. This hazard in manned spacecraft is poorly understood, because the particulate products of polymer thermodegradation are generated under low gravity conditions. Particulate generated from the degradation of PolyTetraFluoroEthylene (PTFE), insulation coating for 20 AWG copper wire (representative of spacecraft application) under intense ohmic heating were studied in terrestrial gravity and microgravity. Microgravity tests were done in a 1.2-second drop tower at the Colorado School of Mines (CSM). Thermophoretic sampling was used for particulate collection. Transmission Electron Microscopy (TEM) and Scanning Transmission Electron Microscopy (STEM) were used to examine the smoke particulates. Image software was used to calculate particle size distribution. In addition to gravity, the color of PTFE insulation has an overwhelming effect on size, shape and morphology of the particulate. Nanometer-sized primary particles were found in all cases, and aggregation and size distribution was dependent on both color and gravity; higher aggregation occurred in low gravity. Particulates from white, black, red and yellow colored PTFE insulations were studied. Elemental analysis of the particulates shows the presence of inorganic pigments.

  3. Physico-chemical and optical properties of combustion-generated particles from coal-fired power plant, automobile and ship engine and charcoal kiln.

    Science.gov (United States)

    Kim, Hwajin

    2015-04-01

    Similarities and differences in physico-chemical and optical properties of combustion generated particles from various sources were investigated. Coal-fired power plant, charcoal kiln, automobile and ship engine were major sources, representing combustions of coal, biomass and two different types of diesel, respectively. Scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectroscopy (EDX) equipped with both SEM and HRTEM were used for physico-chemical analysis. Light absorbing properties were assessed using a spectrometer equipped with an integrating sphere. Particles generated from different combustion sources and conditions demonstrate great variability in their morphology, structure and composition. From coal-fired power plant, both fly ash and flue gas were mostly composed of heterogeneously mixed mineral ash spheres, suggesting that the complete combustion was occurred releasing carbonaceous species out at high temperature (1200-1300 °C). Both automobile and ship exhausts from diesel combustions show typical features of soot: concentric circles comprised of closely-packed graphene layers. However, heavy fuel oil (HFO) combusted particles from ship exhaust demonstrate more complex compositions containing different morphology of particles other than soot, e.g., spherical shape of char particles composed of minerals and carbon. Even for the soot aggregates, particles from HFO burning have different chemical compositions; carbon is dominated but Ca (29.8%), S (28.7%), Na(1%), and Mg(1%) are contained, respectively which were not found from particles of automobile emission. This indicates that chemical compositions and burning conditions are significant to determine the fate of particles. Finally, from biomass burning, amorphous and droplet-like carbonaceous particles with no crystallite structure are observed and they are generally formed by the condensation of low volatile species at low

  4. Development of thermoelectric power generation system utilizing heat of combustible solid waste

    International Nuclear Information System (INIS)

    Kajikawa, T.; Ito, M.; Katsube, I.; Shibuya, E.

    1994-01-01

    The paper presents the development of thermoelectric power generation system utilizing heat of municipal solid waste. The systematic classification and design guideline are proposed in consideration of the characteristics of solid waste processing system. The conceptual design of thermoelectric power generation system is carried out for a typical middle scale incinerator system (200 ton/day) by the local model. Totally the recovered electricity is 926.5 kWe by 445 units (569,600 couples). In order to achieve detailed design, one dimensional steady state model taking account of temperature dependency of the heat transfer performance and thermoelectric properties is developed. Moreover, small scale on-site experiment on 60 W class module installed in the real incinerator is carried out to extract various levels of technological problems. In parallel with the system development, high temperature thermoelectric elements such as Mn-Si and so on are developed aiming the optimization of ternary compound and high performance due to controlled fine-grain boundary effect. The manganese silicide made by shrinking-rate controlled sintering method performs 5 (μW/cm K2) in power factor at 800 K. copyright 1995 American Institute of Physics

  5. Submersible microbial fuel cell for electricity production from sewage sludge

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Olias, Lola Gonzalez; Kongjan, Prawit

    2010-01-01

    A submersible microbial fuel cell (SMFC) was utilized to treatment of sewage sludge and simultaneous generate electricity. Stable power generation (145±5 mW/m2) was produced continuously from raw sewage sludge for 5.5 days. The corresponding total chemical oxygen demand (TCOD) removal efficiency...... of an effective system to treatment of sewage sludge and simultaneous recover energy....

  6. Two-phase high solid anaerobic digestion with dewatered sludge: Improved volatile solid degradation and specific methane generation by temperature and pH regulation.

    Science.gov (United States)

    Wang, Guopeng; Dai, Xiaohu; Zhang, Dong; He, Qunbiao; Dong, Bin; Li, Ning; Ye, Ning

    2018-07-01

    The effects of temperature and pH on volatile solid (VS) degradation and CH 4 production of anaerobic digestion treating high-solid municipal dewatered sludge was studied. There were two single-phase reactors in Group 1: 35 and 55 °C reactors. In Group 2 (G2), acidification phase temperature was 55 °C or 70 °C and digestion phase temperature was 35 °C or 55 °C. G3 was set on the basis of G2 with the initial pH adjusted to 10.0. VS degradation ratio and CH 4 generation ratio of G2 and G3 were higher than G1. In G2, acidification reactors did not show much difference on VS degradation and CH 4 generation. Higher VS degradation ratio with higher CH 4 generation ratio was get in extreme thermophilic/thermophilic-mesophilic systems. In G3, pH adjustment only promoted VS degradation and CH 4 generation in acidification reactors when compared to G2, but the two ratios of the whole systems was not further enhanced. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Cleaning IBL secondary sludge in the tubular plate steam generators; IBL Limpieza de lodos en el secundario de la placa tubular de las generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Montoro de Frutos, E.; Gonzalez Carballo, S.

    2012-07-01

    After cleanings Sludge Lancing using 250bar made from the center lane, identifies an area of solidified remaining sludge on the tube plate. Since late 2010, IBERDROLA-SAVAC has developed Inner System Bundle Lancing (IBL), which locally involves shooting a jet of water at high pressure 590bar directly impacting sludge areas within the tube bundle hard to detach and break into small pieces that can be extracted from GV through a closed circuit suction.

  8. Proceedings of the 1999 international joint power generation conference (FACT-vol. 23). Volume 1: Fuels and combustion technologies; Gas turbines; and Nuclear engineering

    International Nuclear Information System (INIS)

    Penfield, S.R. Jr.; Moussa, N.A.

    1999-01-01

    Papers are arranged under the following topical sections: Gas turbine combustion; Advanced energy conversion; Low NOx solutions; Burner developments; Alternative fuels combustion; Advanced energy conversion technologies; Numerical modeling of combustion; Fluidized bed combustion; Coal combustion; Combustion research; Gasification systems; Mercury emissions; Highly preheated air combustion; Selective catalytic reduction; Special topics in combustion research; Gas turbines and advanced energy; and How can the nuclear industry become more efficient? Papers within scope have been processed separately for inclusion on the database

  9. Phosphorus recovery from sewage sludge char ash

    NARCIS (Netherlands)

    Atienza-Martinez, M.; Gea, G.; Arauzo, J.; Kersten, Sascha R.A.; Kootstra, A.M.J.

    2014-01-01

    Phosphorus was recovered from the ash obtained after combustion at different temperatures (600 °C, 750 °C and 900 °C) and after gasification (at 820 °C using a mixture of air and steam as fluidising agent) of char from sewage sludge fast pyrolysis carried out at 530 °C. Depending on the leaching

  10. A study of paint sludge deactivation by pyrolysis reactions

    Directory of Open Access Journals (Sweden)

    Muniz L.A.R.

    2003-01-01

    Full Text Available The production of large quantities of paint sludge is a serious environmental problem. This work evaluates the use of pyrolysis reaction as a process for deactivating paint sludge that generates a combustible gas phase, a solvent liquid phase and an inert solid phase. These wastes were classified into three types: water-based solvent (latex resin and solvents based on their resins (alkyd and polyurethane. An electrically heated stainless steel batch reactor with a capacity of 579 mL and a maximum pressure of 30 atm was used. Following the reactor, a flash separator, which was operated at atmospheric pressure, partially condensed and separated liquid and gas products. Pressure and temperature were monitored on-line by a control and data acquisition system, which adjusted the heating power supplied to the pyrolysis reactor. Reactions followed an experimental design with two factors (reaction time and temperature and three levels (10, 50 and 90 minutes; 450, 550 and 650degreesC. The response variables were liquid and solid masses and net heat of combustion. The optimal operational range for the pyrolysis process was obtained for each response variable. A significant reduction in total mass of solid waste was obtained.

  11. Biomass combustion power generation technologies: Background report 4.1 for the EU Joule 2+ project: Energy from biomass: An assessment of two promising systems for energy production

    International Nuclear Information System (INIS)

    Van den Broek, R.; Faaij, A.; Van Wijk, A.

    1995-05-01

    New developments in biomass combustion technology in progress tend to go towards efficiencies which come close to the present fossil fuel fired systems. The objective of this study is to give a representation of the state of the art and future prospects of biomass combustion technologies and to compare those on a location-independent basis. This will be done both by a general boiler technology description on the basis of qualitative criteria and by a comparison of most recently built and planned power plants on more quantitative grounds. The methodology which has been used in gathering, selecting, presenting and comparing the information is discussed in chapter 2. In chapter 3, a general introduction is given on some basic principles of biomass combustion technology. This includes the combustion process, the Rankine steam cycle and NO x formation. Different boiler technologies which are in use for biomass combustion power generation are discussed in chapter 4. The main groups of boilers which are discussed are the pile burners, stoker fired boilers, suspension fired boilers and fluidized bed boilers. The description focuses on aspects such as construction, operation, fuel requirements, efficiencies and emissions. Chapter 5 deals with individual existing or planned biomass combustion plants, resulting from an international inventory. All the different technologies which have been discussed in chapter 4 are discussed in chapter 5 in the context of complete power plants. The information which is presented for each plant comprises a technical description, efficiencies, emissions and investment costs. At the end of chapter 5 an overview of comparable data from the literature is given, as well as an overview of the results of the inventory. 32 figs., 28 tabs., 4 appendices., 51 refs

  12. Solidifying power station resins and sludges

    International Nuclear Information System (INIS)

    Willis, A.S.D.; Haigh, C.P.

    1984-01-01

    Radioactive ion exchange resins and sludges arise at nuclear power stations from various operations associated with effluent treatment and liquid waste management. As the result of an intensive development programme, the Central Electricity Generating Board (CEGB) has designed a process to convert power station resins and sludges into a shielded, packaged solid monolithic form suitable for final disposal. Research and development, the generic CEGB sludge/resin conditioning plant and the CEGB Active Waste Project are described. (U.K.)

  13. Basic Study on Sludge Concentration and Dehydration with Ultrasonic Exposure

    Science.gov (United States)

    Sawada, Yuta; Nagashima, Satoshi; Uchida, Takeyoshi; Kawashima, Norimichi; Takeuchi, Shinichi; Akita, Masashi; Nagaoka, Hiroshi

    2005-06-01

    We study the condensation of sludge and the improvement of the dehydration efficiency of sludge by acoustic cavitation for efficiency improvement and cost reduction in water treatment. An ultrasound wave was irradiated into activated sludge in the water tank of our ultrasound exposure system and a standing wave acoustic field was formed using a vibrating disk driven by a Langevin-type transducer. The vibrating disk was mounted on the bottom of the water tank. Acoustic cavitation was generated in the activated sludge suspension and the sludge was floated to the water surface by ultrasound exposure with this system. We observed B-mode ultrasound images of the activated sludge suspension before ultrasound exposure and that of the floated sludge and treated water after ultrasound exposure. The ultrasound diagnostic equipment was used for the observation of the B-mode ultrasound images of the sludge. It was found that the sludge floated to the water surface because of adhesion of microbubbles generated by acoustic cavitation to the sludge particles, which decreased the sludge density. It can be expected that the drifting sludge in water can be recovered by the flotation thickening method of sludge as an application of the results of this study. It is difficult to recover the drifting sludge in water by the conventional gravity thickening method.

  14. Boosting methane generation by co-digestion of sludge with fruit and vegetable waste: Internal environment of digester and methanogenic pathway.

    Science.gov (United States)

    Di Maria, Francesco; Barratta, Martino

    2015-09-01

    The effects of anaerobic co-digestion of waste-mixed sludge with fruit and vegetable waste (FVW) on the methane generation of a mesophilic digester was investigated. Organic loading rates (OLR) were 1.46kgVS/m(3)day, 2.1kgVS/m(3)day and 2.8kgVS/m(3)day. Increase in the OLR due to FVW co-digestion caused modification of the internal environment of the digester, mainly in terms of N-NH4 (mg/L). Corresponding microbial populations were investigated by metagenomic high-throughput sequencing. Maximum specific bio-methane generation of 435 NLCH4 per kgVS feed was achieved for an OLR of 2.1kgVS/m(3)day, which corresponded to a biomethane generation per kgVS removed of about 1700 NLCH4. In these conditions the methanogenic pathway was dominated by aceticlastic Methanosaeta and hydrogenotrophic/aceticlastic Methanoscarcinae. Ammonia concentration in the digester resulted a key parameter for enhancing syntrophic acetate oxidation, enabling a balanced aceticlastic and hydrogenotrophic/aceticlastic methanogenic pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Electricity generation using chocolate industry wastewater and its treatment in activated sludge based microbial fuel cell and analysis of developed microbial community in the anode chamber.

    Science.gov (United States)

    Patil, Sunil A; Surakasi, Venkata Prasad; Koul, Sandeep; Ijmulwar, Shrikant; Vivek, Amar; Shouche, Y S; Kapadnis, B P

    2009-11-01

    Feasibility of using chocolate industry wastewater as a substrate for electricity generation using activated sludge as a source of microorganisms was investigated in two-chambered microbial fuel cell. The maximum current generated with membrane and salt bridge MFCs was 3.02 and 2.3 A/m(2), respectively, at 100 ohms external resistance, whereas the maximum current generated in glucose powered MFC was 3.1 A/m(2). The use of chocolate industry wastewater in cathode chamber was promising with 4.1 mA current output. Significant reduction in COD, BOD, total solids and total dissolved solids of wastewater by 75%, 65%, 68%, 50%, respectively, indicated effective wastewater treatment in batch experiments. The 16S rDNA analysis of anode biofilm and suspended cells revealed predominance of beta-Proteobacteria clones with 50.6% followed by unclassified bacteria (9.9%), alpha-Proteobacteria (9.1%), other Proteobacteria (9%), Planctomycetes (5.8%), Firmicutes (4.9%), Nitrospora (3.3%), Spirochaetes (3.3%), Bacteroides (2.4%) and gamma-Proteobacteria (0.8%). Diverse bacterial groups represented as members of the anode chamber community.

  16. Activated Sludge.

    Science.gov (United States)

    Saunders, F. Michael

    1978-01-01

    Presents the 1978 literature review of wastewater treatment. This review covers: (1) activated sludge process; (2) process control; (3) oxygen uptake and transfer; (4) phosphorus removal; (5) nitrification; (6) industrial wastewater; and (7) aerobic digestion. A list of 136 references is also presented. (HM)

  17. Hydrogen Generation from Ammonia Borane and Water Through the Combustion Reactions with Mechanically Alloyed Al/Mg Powder

    Science.gov (United States)

    2014-08-11

    mechanisms during combustion of these mixtures. For this purpose, isotopic tests, involving use of heavy water and mass-spectroscopy of gaseous combustion...Comparison of hydrogen release from various boron -based chemical hydrides (8)....................7 Figure 2. Comparison of hydrogen release from...acquired from the pressure increase. Isotopic tests (deuterium) were used for revealing the reaction mechanisms. CHAPTER 2: LITERATURE REVIEW 2.1

  18. Opportunities in pulse combustion

    Science.gov (United States)

    Brenchley, D. L.; Bomelburg, H. J.

    1985-10-01

    In most pulse combustors, the combustion occurs near the closed end of a tube where inlet valves operate in phase with the pressure amplitude variations. Thus, within the combustion zone, both the temperature and the pressure oscillate around a mean value. However, the development of practical applications of pulse combustion has been hampered because effective design requires the right combination of the combustor's dimensions, valve characteristics, fuel/oxidizer combination, and flow pattern. Pulse combustion has several additional advantages for energy conversion efficiency, including high combustion and thermal efficiency, high combustion intensity, and high convective heat transfer rates. Also, pulse combustion can be self-aspirating, generating a pressure boost without using a blower. This allows the use of a compact heat exchanger that may include a condensing section and may obviate the need for a chimney. In the last decade, these features have revived interest in pulse combustion research and development, which has resulted in the development of a pulse combustion air heater by Lennox, and a pulse combustion hydronic unit by Hydrotherm, Inc. To appraise this potential for energy savings, a systematic study was conducted of the many past and present attempts to use pulse combustion for practical purposes. The authors recommended areas where pulse combustion technology could possibly be applied in the future and identified areas in which additional R and D would be necessary. Many of the results of the study project derived from a special workshop on pulse combustion. This document highlights the main points of the study report, with particular emphasis on pulse combustion application in chemical engineering.

  19. Characterization of products from fluidized-bed combustion of coal.

    Science.gov (United States)

    Bednarik, V; Vondruska, M; Sild, M; Vondruskova, E

    2000-11-01

    The technology of fluidized-bed combustion (FBC) of coal generates byproducts that have a series of unique characteristics and potential uses in technological practice. In this study, the products of fluidized-bed combustion (FBC-P) of coal derived from Moravian heat stations, a.s. Zlin, Cinergy Global Resources, Czech Republic, were characterized. Particular attention was paid to determining the chemical composition of FBC-P, the content of polycyclic aromatic hydrocarbons (PAHs) and toxic metals in the water leachates of these FBC-P, the content of unburned carbon, the capability of FBC-P to solidify with water and form a solid matrix, and the method for discovering optimum mixing water content for FBC-P solidification. The results suggest that one of the qualitatively more important means of utilizing FBC-P could be their application during solidification/stabilization (S/S) of wastes, particularly wastewater treatment sludges.

  20. Sludge busters

    International Nuclear Information System (INIS)

    Pichon, Max

    2010-01-01

    Full text: A few years ago, For Earth developed low energy sub-surface aeration systems to increase the biological activity in the wastewater sludge ponds. Then came the idea to introduce probiotic bacteria to really ramp up the process, which promises massive time and cost savings in sludge management. Increasing the volumes of specific bacteria reactivates the sludge, accelerating biological nutrient removal in general and, by tailoring the bacteria, targeting specific organic waste types. The technology is already running at more than 30 councils across NSW and in some commercial settings, such as dairy farms. Shane McKibbin, GM of For Earth, said the 'Probiotic, Low Energy Aeration System' offers considerable upside. “The cost savings have been enormous with some councils, including the work done at Woolgoolga Water Reclamation Plant at Coffs Harbour,” he said. Sludge settling in wastewater treatment plant lagoons is typically pumped out, centrifuged to remove water and then landfilled. In Woolgoolga's case that process was costing Coffs Harbour Water $150 a cubic metre; McKibbin said they've slashed that to a measly $5 a cubic metre. An array of 'industrial air stones' is dropped 1m below the surface to create an oxygenated blanket across the surface, overcoming the tendency of sludge ponds to stagnate. The key though is floating probiotic dosing lines across the surface, which kick-starts the probiotics process. “Previously, some operators just wanted to throw it on with a bucket, so the bacteria would get thrown into one corner of the pond. But since we introduced the dosing system it has really improved the overall performance,” said McKibbin.The dosing pump system automatically applies the bacteria into the dosing line according to a specified program, ensuring the probiotics are spread out across the pond and across the week. “I would say it improves and accelerates the result by 30 per cent,” he adds.

  1. Enhanced methane generation during theromophilic co-digestion of confectionary waste and grease-trap fats and oils with municipal wastewater sludge.

    Science.gov (United States)

    Gough, Heidi L; Nelsen, Diane; Muller, Christopher; Ferguson, John

    2013-02-01

    Recent interest in carbon-neutral biofuels has revived interest in co-digestion for methane generation. At wastewater treatment facilities, organic wastes may be co-digested with sludge using established anaerobic digesters. However, changes to organic loadings may induce digester instability, particularly for thermophilic digesters. To examine this problem, thermophilic (55 degrees C) co-digestion was studied for two food-industry wastes in semi-continuous laboratory digesters; in addition, the wastes' biochemical methane potentials were tested. Wastes with high chemical oxygen demand (COD) content were selected as feedstocks allowing increased input of potential energy to reactors without substantially altering volumetric loadings. Methane generation increased while reactor pH and volatile solids remained stable. Lag periods observed prior to methane stimulation suggested that acclimation of the microbial community may be critical to performance during co-digestion. Chemical oxygen demand mass balances in the experimental and control reactors indicated that all of the food industry waste COD was converted to methane.

  2. Lump wood combustion process

    Science.gov (United States)

    Kubesa, Petr; Horák, Jiří; Branc, Michal; Krpec, Kamil; Hopan, František; Koloničný, Jan; Ochodek, Tadeáš; Drastichová, Vendula; Martiník, Lubomír; Malcho, Milan

    2014-08-01

    The article deals with the combustion process for lump wood in low-power fireplaces (units to dozens of kW). Such a combustion process is cyclical in its nature, and what combustion facility users are most interested in is the frequency, at which fuel needs to be stoked to the fireplace. The paper defines the basic terms such as burnout curve and burning rate curve, which are closely related to the stocking frequency. The fuel burning rate is directly dependent on the immediate thermal power of the fireplace. This is also related to the temperature achieved in the fireplace, magnitude of flue gas losses and the ability to generate conditions favouring the full burnout of the fuel's combustible component, which, at once ensures the minimum production of combustible pollutants. Another part of the paper describes experiments conducted in traditional fireplaces with a grate, at which well-dried lump wood was combusted.

  3. REEMISSION OF MERCURY COMPOUNDS FROM SEWAGE SLUDGE DISPOSAL

    Directory of Open Access Journals (Sweden)

    Beata Janowska

    2016-12-01

    Full Text Available The sewage sludge disposal and cultivation methods consist in storage, agricultural use, compost production, biogas production or heat treatment. The sewage sludge production in municipal sewage sludge treatment plants in year 2013 in Poland amounted to 540.3 thousand Mg d.m. The sewage sludge for agricultural or natural use must satisfy chemical, sanitary and environmental safety requirements. The heavy metal content, including the mercury content, determines the sewage sludge disposal method. Mercury has a high chemical activity and biological form compounds with different properties. The properties of the mercury present in sewage sludge or composts, its potential bioavailability depend on its physicochemical forms. Different forms of mercury, which are found in soil and sediments and sewage sludge, may be determined using various techniques sequential extraction. In order to assess the bioavailability the analysis of fractional of mercury in samples of sewage sludge and composts was made. For this purpose the analytical procedure based on a four sequential extraction process was applied. Mercury fractions were classified as exchangeable (EX, base soluble (BS, acids soluble (AS and oxidizable (OX. This article presents the research results on the mercury compounds contents in sewage sludge subjected to drying process, combustion and in composted sewage sludge. During drying and combustion process of the sewage sludge, mercury transforms into volatile forms that could be emitted into the atmosphere. The mercury fractionation in composted sewage sludge proved that mercury in compost occurs mainly in an organic fraction and in a residual fraction that are scarce in the environment.

  4. The Effects of the Location of Au Additives on Combustion-generated SnO2 Nanopowders for CO Gas Sensing

    Science.gov (United States)

    Bakrania, Smitesh D.; Wooldridge, Margaret S.

    2010-01-01

    The current work presents the results of an experimental study of the effects of the location of gold additives on the performance of combustion-generated tin dioxide (SnO2) nanopowders in solid state gas sensors. The time response and sensor response to 500 ppm carbon monoxide is reported for a range of gold additive/SnO2 film architectures including the use of colloidal, sputtered, and combustion-generated Au additives. The opportunities afforded by combustion synthesis to affect the SnO2/additive morphology are demonstrated. The best sensor performance in terms of sensor response (S) and time response (τ) was observed when the Au additives were restricted to the outermost layer of the gas-sensing film. Further improvement was observed in the sensor response and time response when the Au additives were dispersed throughout the outermost layer of the film, where S = 11.3 and τ = 51 s, as opposed to Au localized at the surface, where S = 6.1 and τ = 60 s. PMID:22163586

  5. OXYCOAL-AC: Towards development of a zero-CO2-emission coal combustion process for efficient power generation

    International Nuclear Information System (INIS)

    Toporov, D.; Heil, P.; Foerster, M.; Kneer, R.

    2010-01-01

    The OXYCOAL-AC cooperative research project, presented here, aims at the development of the main components for an integrated zero-CO 2 emission power plant process which comprises combustion of pulverised coal in a mixture of recirculated flue gas (RFG) and oxygen produced from a ceramic ion transport membrane (ITM). This article focuses on the specifics of coal combustion in a CO 2 /O 2 atmosphere including flame stability and related burner design as well as the changes in the heat transfer inside an oxy-firing utility scale furnace. The membrane-based air separation modules and their design for oxycoal conditions are reviewed as well. (authors)

  6. Inclusion of preferential diffusion in simulations of premixed combustion of hydrogen/methane mixtures with flamelet generated manifolds

    NARCIS (Netherlands)

    Swart, J.A.M.de; Bastiaans, R.J.M.; Oijen, J.A. van; Goey, L.P.H. de; Cant, R.S.

    2010-01-01

    In this paper we study the possibility to account for preferential diffusion effects in lean turbulent premixed flames in numerical predictions with reduced chemistry. We studied the situation when hydrogen is added to methane at levels of 20% and 40% by volume in the fuel, at lean combustion (φ=

  7. Health effects engineering of coal and biomass combustion particulates: influence of zinc, sulfur and process changes on potential lung injury from inhaled ash

    Energy Technology Data Exchange (ETDEWEB)

    Art Fernandez; Jost O.L. Wendt; Mark L. Witten [University of Arizona, Tucson, AZ (US). Department of Chemical and Environmental Engineering

    2005-07-01

    This paper is concerned with health effects of the ash aerosol formed from the co-combustion of municipal sewage sludge with pulverized coal. By employing the methods of Health Effects Engineering, one can determine not only which fuel attributes are likely to contribute to lung injury, but also how tendencies of the ash to cause lung injury can be engineered out of the combustion process. Initial results showed that inhalation of ash from the co-combustion of municipal sewage sludge (MSS) and pulverized coal caused much greater lung damage in mice, as measured by lung permeability increase, than that of coal ash, or MSS ash, alone. MSS contains substantial quantities of zinc but little sulfur, while coal contains sulfur but littlezinc. Experiments were conducted to determine the health effects of combustion generated zinc particles and zinc plus sulfur particles. Zinc without sulfur led to normal behavior as far as lung permeability was concerned. Zinc with sulfur added led to the abnormal behavior noted also in the coal+MSS experiments. Therefore, the bad actor was identified to be zinc together with sulfur, and that was why the co-combustion of coal and MSS caused greater lung injury than the combustion of either fuel alone. Injection of a kaolinite sorbent downstream of the flame, but above the Zn dew point, can sequester the Zn, and react it to form a new species which was shown to be relatively benign. 18 refs., 9 figs., 1 tab.

  8. Combustion Noise in Modern Aero-Engines

    OpenAIRE

    Duran, I.; Moreau, S.; Nicoud, F.; T., Livebardon; Bouty, E.; Poinsot, T.

    2014-01-01

    International audience; Combustion noise has recently been the subject of attention of both the aeroacoustic and the combustion research communities. Over the last decades, engine manufacturershave made important efforts to significantly reduce fan and jet noise, which increased the relative importance of combustion noise. Two main mechanisms of combustion-noise generation have been identified: direct combustion noise, generated by acoustic waves propagating to the outlet, and indirect combus...

  9. Burners. The decrease of nitrogen oxides in combustion process: the 2 nd generation GR LONOxFLAM burner; Les bruleurs, la reduction des oxydes d`azote dans la combustion: bruleur GR LONOxFLAM de 2. generation

    Energy Technology Data Exchange (ETDEWEB)

    Gauthier, J.C. [EGCI Pillard, 13 - Marseille (France)

    1997-12-31

    The Pillard company has developed, in cooperation with GDF (the French national gas utility), the GR-LONOxFLAM burner concept for reducing NOx emission levels and solid combustion products. The concept consists, for gaseous fuels, in the combination of an internal recirculation and a gas staging process; for liquid fuels, a separated flame process and air staging are combined. These concepts allow for an important reduction in NOx and non-burned residues, even with standard-size burners

  10. Hydrogen generation and foaming during tests in the GFPS simulating DWPF operations with Tank 42 sludge and CST

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, D.C.

    1999-12-08

    This report summarizes the pilot-scale research requested by the salt disposition team to examine the effect of crystalline silicotitanate (CST) resin with adsorbed noble metals on the maximum hydrogen generation rate produced during the DWPF melter feed preparation processes.

  11. HYDROGEN GENERATION FROM SLUDGE SAMPLE BOTTLES CAUSED BY RADIOLYSIS AND CHEMISTRY WITH CONCETNRATION DETERMINATION IN A STANDARD WASTE BOX (SWB) OR DRUM FOR TRANSPORT

    Energy Technology Data Exchange (ETDEWEB)

    RILEY DL; BRIDGES AE; EDWARDS WS

    2010-03-30

    A volume of 600 mL of sludge, in 4.1 L sample bottles (Appendix 7.6), will be placed in either a Super Pig (Ref. 1) or Piglet (Ref. 2, 3) based on shielding requirements (Ref. 4). Two Super Pigs will be placed in a Standard Waste Box (SWB, Ref. 5), as their weight exceeds the capacity of a drum; two Piglets will be placed in a 55-gallon drum (shown in Appendix 7.2). The generation of hydrogen gas through oxidation/corrosion of uranium metal by its reaction with water will be determined and combined with the hydrogen produced by radiolysis. The hydrogen concentration in the 55-gallon drum and SWB will be calculated to show that the lower flammability limit of 5% hydrogen is not reached. The inner layers (i.e., sample bottle, bag and shielded pig) in the SWB and drum will be evaluated to assure no pressurization occurs as the hydrogen vents from the inner containers (e.g., shielded pigs, etc.). The reaction of uranium metal with anoxic liquid water is highly exothermic; the heat of reaction will be combined with the source term decay heat, calculated from Radcalc, to show that the drum and SWB package heat load limits are satisfied. This analysis does five things: (1) Estimates the H{sub 2} generation from the reaction of uranium metal with water; (2) Estimates the H{sub 2} generation from radiolysis (using Radcalc 4.1); (3) Combines both H{sub 2} generation amounts, from Items 1 and 2, and determines the percent concentration of H{sub 2} in the interior of an SWB with two Super Pigs, and the interior of a 55-gallon drum with two Piglets; (4) From the combined gas generation rate, shows that the pressure at internal layers is minimal; and (5) Calculates the maximum thermal load of the package, both from radioactive decay of the source and daughter products as calculated/reported by Radcalc 4.1, and from the exothermic reaction of uranium metal with water.

  12. Use of artificial intelligence techniques for optimisation of co-combustion of coal with biomass

    Energy Technology Data Exchange (ETDEWEB)

    Tan, C.K.; Wilcox, S.J.; Ward, J. [University of Glamorgan, Pontypridd (United Kingdom). Division of Mechanical Engineering

    2006-03-15

    The optimisation of burner operation in conventional pulverised-coal-fired boilers for co-combustion applications represents a significant challenge This paper describes a strategic framework in which Artificial Intelligence (AI) techniques can be applied to solve such an optimisation problem. The effectiveness of the proposed system is demonstrated by a case study that simulates the co-combustion of coal with sewage sludge in a 500-kW pilot-scale combustion rig equipped with a swirl stabilised low-NOx burner. A series of Computational Fluid Dynamics (CFD) simulations were performed to generate data for different operating conditions, which were then used to train several Artificial Neural Networks (ANNs) to predict the co-combustion performance. Once trained, the ANNs were able to make estimations of unseen situations in a fraction of the time taken by the CFD simulation. Consequently, the networks were capable of representing the underlying physics of the CFD models and could be executed efficiently for a large number of iterations as required by optimisation techniques based on Evolutionary Algorithms (EAs). Four operating parameters of the burner, namely the swirl angles and flow rates of the secondary and tertiary combustion air were optimised with the objective of minimising the NOx and CO emissions as well as the unburned carbon at the furnace exit. The results suggest that ANNs combined with EAs provide a useful tool for optimising co-combustion processes.

  13. Measures for a quality combustion (combustion chamber exit and downstream); Mesures pour une combustion de qualite (sortie de chambre de combustion et en aval)

    Energy Technology Data Exchange (ETDEWEB)

    Epinat, G. [APAVE Lyonnaise, 69 (France)

    1996-12-31

    After a review of the different pollutants related to the various types of stationary and mobile combustion processes (stoichiometric, reducing and oxidizing combustion), measures and analyses than may be used to ensure the quality and efficiency of combustion processes are reviewed: opacimeters, UV analyzers, etc. The regulation and control equipment for combustion systems are then listed, according to the generator capacity level

  14. Electricity generation from solid biomass via co-combustion with coal. Energy and emission balances from a German case study

    International Nuclear Information System (INIS)

    Hartmann, D.; Kaltschmitt, M.

    1999-01-01

    The environmental effects of electricity production from different biofuels by means of co-combustion with hard coal in existing coal fired power plants are analysed and compared to electricity production from hard coal alone based on Life Cycle Analysis (LCA). The use of straw and residual wood at a 10% blend with coal in an existing power plant in the southern part of Germany shows that all investigated environmental effects are significantly lower if biomass is used instead of coal. Thus based on the available and proven technology of co-combustion of hard coal and biomass in existing power plants a significant contribution could be made to a more environmentally sound energy system compared to using coal alone. (author)

  15. Ash transformation and deposition behavior during co-firing biomass with sewage sludge

    DEFF Research Database (Denmark)

    Wang, Liang; Wu, Hao; Jensen, Peter Arendt

    In the present work, the ash transformation and deposition behavior during wheat straw and wood waste combustion were investigated by combustion experiments in an entrained flow reactor. The influence of sewage sludge addition on ash chemistry and deposition tendency was also studied. During...... deposits, which mainly contain K-silicates, K-Al-silicates and K-Ca-silicates. The sewage sludge addition significantly reduced the water soluble K and Na in the fly ash from wheat straw and wood waste combustion. Compared to pure wheat straw and wood waste, the ash deposition rates were increased due...... to sewage sludge addition. However, the ash deposition propensity decreased significantly. In addition, the content of water soluble K and Cl in the deposits reduced as a result of sewage sludge addition. The results from present work suggest co-firing of sewage sludge could alleviate deposit formation...

  16. Life cycle assessment comparing the treatment of surplus activated sludge in a sludge treatment reed bed system with mechanical treatment on centrifuge

    DEFF Research Database (Denmark)

    Larsen, Julie Dam; Hoeve, Marieke ten; Nielsen, Steen

    2018-01-01

    In Denmark, the conventional method for treating sewage sludge is mechanical dewatering and subsequent storage. However, sludge treatment reed bed systems, which are holistic sludge treatment facilities combining the dewatering, mineralisation and storage of sludge, have been more common during...... the last three decades. Treatment of sludge in a sludge treatment reed bed system can be combined with post-treatment (further dewatering and mineralisation) on a stockpile area. This study aimed to compare the environmental performances of a mechanical sludge treatment method with the sludge treatment...... reed bed system strategy, using the life cycle assessment approach and a life cycle inventory based on newly generated data obtained from Danish reference facilities. The scenarios based on the different treatment methods were initiated by sludge entering the sludge treatment reed bed system...

  17. Environmental Assessment of Sewage Sludge Management – Focusing on Sludge Treatment Reed Bed Systems

    DEFF Research Database (Denmark)

    Larsen, Julie Dam

    ; however, in the late 1980s, sludge treatment reed bed (STRB) systems were intro-duced in Denmark and in 2016, more than 100 STRB systems were operating in the country. Sludge treatment in STRB systems is often considered more environmentally friendly compared to mechanical sludge treatment technologies......, albeit only a few life cycle assess-ments (LCAs) comparing the environmental performances of sludge treatment technologies include STRB systems. Furthermore, as data on the STRB system technology suitable for LCA are scarce, the results of these LCAs are unreliable. The project aimed at generating data...... in treated sludge when applied to the land. The overall goal of the project was to perform an LCA comparing the environmental performance of the STRB system technology with a conventional technology based on mechanical dewatering of sludge on a decanter centrifuge and subsequent storage. Geographically...

  18. Fuel reactivity and release of pollutants and alkali vapours in pressurized combustion for combined cycle power generation

    Energy Technology Data Exchange (ETDEWEB)

    Aho, M.; Haemaelaeinen, J.; Paakkinen, K.; Rantanen, J. [VTT Energy, Jyvaeskylae (Finland); Hernberg, R.; Haeyrinen, V.; Joutsenoja, T. [Tampere Univ. of Technology (Finland). Lab. of Plasma Technology

    1996-12-01

    This project forms a part of the overall Pressurized Power Coal Combustion Project Area (PPFC) which aims at an assessment of the viability and technical merits of pressurized pulverized coal combustion, in an atmosphere of recycled flue gas and oxygen in a coordinated and harmonized programme. The objective of the research at Technical Research Centre of Finland (VTT) and Tampere University of Technology (TUT) is aimed at determining the consequences of solid fuel burning in a mixture of oxygen and recycled flue gases. Combustion conditions of a pressurized entrained flow of pulverized coal and char particles in PEFR are determined with high precision. The effects of experimental parameters on the formation of nitrogen oxides (N{sub 2}O, NO and NO{sub 2}) and gaseous alkali compounds (indicated as NaX(g) and KX(g)) are studied. An effective on-line analysis method for vaporised Na and K compounds was developed. The dependency between particle temperatures and the vaporisation of Na and K was measured with three coals. The results show that alkali removal before gas turbines is always necessary with these coals if combusted in combined cycles. Pressure decreases the formation of NO and has usually no clear effect on the formation of N{sub 2}O. The order of NO/N{sub 2}O ratios correspond to fuel-O/fuel-N ratios. Increase of PO{sub 2} (oxygen concentration) of combustion gas increases the formation of NO{sub 2}. Remarkable concentrations of NO{sub 2} were often measured at high PO{sub 2} at 800-850 deg C. Therefore, NO{sub 2} should be measured from pressurized fluidized bed reactors. Some trends of the formation of NO{sub 2} with coal differ clearly from those with its parent char: N{sub 2}O formation is not strongly temperature dependent with char, and the concentrations of N{sub 2}O formed from char are much lower than those of coal. PO{sub 2} does not effect on the formation of NO from char in the studied range

  19. Sludge quantification at water treatment plant and its management scenario.

    Science.gov (United States)

    Ahmad, Tarique; Ahmad, Kafeel; Alam, Mehtab

    2017-08-15

    Large volume of sludge is generated at the water treatment plants during the purification of surface water for potable supplies. Handling and disposal of sludge require careful attention from civic bodies, plant operators, and environmentalists. Quantification of the sludge produced at the treatment plants is important to develop suitable management strategies for its economical and environment friendly disposal. Present study deals with the quantification of sludge using empirical relation between turbidity, suspended solids, and coagulant dosing. Seasonal variation has significant effect on the raw water quality received at the water treatment plants so forth sludge generation also varies. Yearly production of the sludge in a water treatment plant at Ghaziabad, India, is estimated to be 29,700 ton. Sustainable disposal of such a quantity of sludge is a challenging task under stringent environmental legislation. Several beneficial reuses of sludge in civil engineering and constructional work have been identified globally such as raw material in manufacturing cement, bricks, and artificial aggregates, as cementitious material, and sand substitute in preparing concrete and mortar. About 54 to 60% sand, 24 to 28% silt, and 16% clay constitute the sludge generated at the water treatment plant under investigation. Characteristics of the sludge are found suitable for its potential utilization as locally available construction material for safe disposal. An overview of the sustainable management scenario involving beneficial reuses of the sludge has also been presented.

  20. Integral study of sewage sludges

    International Nuclear Information System (INIS)

    1994-01-01

    Sewage sludges are the by-product generated during the treatment process of waste water, and they are conformed by a solid phase which origin is the accumulation of pollutant materials which has been added to water during natural and anthropogenic activities. Its handling is one of the most serious problems faced by water treatment plants which involve the production, gathering, transportation, re utilization and final disposal of sewage sludges. The main purpose of this project is to perform a technical evaluation of the process of sewage sludge irradiation for its possible application as a choice for treatment and final disposal. Irradiation with gammas from Cobalt-60 shows effectiveness in disinfestation of sewage sludges, since they reduce six times the microbial population with a 7 KGy dose. In like manners with doses of 10 KGy is possible to bring down in 70 % the concentration of organic compounds, as well as to eliminate the presence of 6 to 22 organic compounds on samples of sewage sludges. The whole content of this work is presented in six sections: Introduction, Antecedents, Methodology, Conclusions, Suggestions and Bibliography. (Author)

  1. Heat transfer characteristics of porous sludge deposits and their impact on the performance of commercial steam generators

    International Nuclear Information System (INIS)

    Kreider, M.A.; White, G.A.; Varrin, R.D.; Ouzts, P.J.

    1998-12-01

    Steam generator (SG) fouling, in the form of corrosion deposits on the secondary sides of SG tubes, has been known to occur in almost all commercial US nuclear PWR (pressurized water reactor) plants. The level of fouling, as measured by the quantity of corrosion products that form, varies widely from plant to plant. In addition, the effect of SG fouling, as measured by a decrease in effective heat-transfer coefficient, has also varied substantially among commercial US plants. While some have observed large decreases in heat transfer, others have noted little change in performance despite the presence of significant quantities of secondary corrosion layers on their SG tubes. This observation has led to considerable confusion about what role secondary deposits play in causing heat-transfer degradation in SGs. As will become clear later in this report, secondary deposits can have a wide range of effects on heat transfer, from highly resistive to slightly enhancing (reflected by negative fouling). These different behaviors are the result of differences in deposit thickness, composition, and morphology. The main focus of this report is an investigation of the effects of secondary deposits on SG thermal performance. This investigation includes compilation of detailed information on the properties of tube scale at five commercial US nuclear plants and corresponding information characterizing SG thermal performance at these plants

  2. Plant with at least one internal combustion engine which propels a current generator and with at least one heat consumer. Anlage mit mindestens einer Brennkraftmaschine, die einen Stromgenerator antreibt, und mindestens einem Waermeverbraucher

    Energy Technology Data Exchange (ETDEWEB)

    Hoehn, R.; Lelanz, B.

    1990-04-05

    The invention pertains to a technique for cogeneration, with at least one current generator which is driven by an internal combustion engine; with one and/or several heat consumers whose heat requirement is covered at least partially from the waste heat of the internal combustion engine. The waste heat is recovered immediately at its source, i.e. the cooling water header, air preheating, exhaust gas mains; it is fed to the heating space of the heat consumer.

  3. Study of highly efficient power generation system based on chemical-looping combustion; Chemical loop nenshoho ni yoru kokoritsu hatsuden system no kaihatsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, S.; Suzuki, T.; Yamamoto, M. [Tokyo Institute of Technology, Tokyo (Japan). Research Laboratory of Resources Utilization

    1997-02-01

    This paper describes the research and development of power generation system by means of chemical-looping combustion. For this system, fuel flows in a reduction reactor and air flows in an oxidation reactor. These two flows are separated. As a result, recovery of CO2 without energy consumption, drastic improvement of power generation efficiency, and suppression of NOx emission are expected. To realize the above, two promising candidates, NiCoO2/YSZ and NiO2/NiAl2O4, have been found as recycle solid particles between the both reactors. These have excellent oxidation/reduction cycle characteristics. By these particles as well as the existing particle, NiO/YSZ, practical application of the chemical-looping combustion is realized. Besides LNG, coal and hydrogen were considered as fuels. When using coal or hydrogen, it was found that temperature of the reduction reactor should be increased the same as that of the oxidation reactor. This is a different point from a case using LNG as a fuel. 5 refs., 2 figs.

  4. Consumption and combustion efficiency in a generator engine using biodiesel; Consumo e eficiencia de combustao em um motor gerador utilizando biodisel

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Joao Paulo Barreto; Delmond, Josue G.; Couto, Rodney Ferreira; Neiva Filho, Neyber Cristiano; Reis, Elton F. dos [Universidade Estadual de Goias (UNUCET/UEG), Anapolis, GO (Brazil). Unidade Universitaria de Ciencias Exatas e Tecnologicas], Email: bcunha_2@hotmail.com

    2011-07-01

    Due to the increasing demand for biodiesel, associated to the aim of reduction in pollutants emissions, technical feasibility studies are increasingly needed. This study aimed to evaluate the use of biodiesel in different concentrations (B5, B10, B20, B50, B75 and B100) in a diesel generator set, with an engine with 3,73 KW four-stroke with direct injection. Assays were performed to quantify the hourly fuel consumption and emission of gases under different conditions of engine operation, through demands of electrical loads (500 W, 1.000W, 1.500W, 2,000 W and off) connected to the generator group. A completely randomized design was used with 5x6 factorial arrangement of treatment, six of biodiesel blends and five electric load demands, with three repetitions. The results demonstrated that the mixtures showed a significant difference in fuel consumption and combustion efficiency, and revealed that the use of biodiesel in higher concentrations in general provided a combustion process more efficient compared to conventional diesel. (author)

  5. Generating Units

    Data.gov (United States)

    Department of Homeland Security — Generating Units are any combination of physically connected generators, reactors, boilers, combustion turbines, and other prime movers operated together to produce...

  6. Scrutinizing the combustion, performance and emissions of safflower biodiesel–kerosene fueled diesel engine used as power source for a generator

    International Nuclear Information System (INIS)

    Aydın, Hüseyin

    2016-01-01

    Highlights: • Effects of kerosene addition to biodiesel in a diesel engine were investigated. • S90&K10, S75&K25 and S50&K50 were tested and comparisons have been made with D2. • Patterns of combustion parameters have found be quite similar for blend fuels and D2. • The highest efficiency value is obtained for S50&K50 blend. • HC emissions a bit increased and NOx emissions were decreased. - Abstract: When neat biodiesel or its blends with diesel fuel that contain high amounts of biodiesel are used in diesel engines some operational problems such as poor injection, bad atomization and incomplete combustion occur mainly due to higher viscosity and surface tension. Engine problems with the use of biodiesel–fuel blends that contain higher percentages of biodiesel need to be solved in order to utilize the advantages of biodiesel in environmental and economical ways. The mentioned problems can also be solved by blending biodiesel with another low density or viscosity fuel such as kerosene. In present study biodiesel was produced from safflower oil. S90&K10, S75&K25 and S50&K50 were prepared by blending biodiesel with kerosene. A 4 cylinder diesel engine that was used to drive an electric generator was used to deeply investigate the similarity of combustion, performance and emission characteristics of the blend fuels to D2. All experiments were carried out at constant loads of 3.6, 7.2 and 10.8 kW generated powers. Patterns of combustion parameters found to be quite similar for blends and D2 fuel. NO x emissions were considerably decreased with percentages of 68.2%, 56.9% and 55.1% for S50&K50, S75&K25 and S90&K10, respectively while unburned HC emissions were a bit increased. Mass fuel consumption and BSFC were slightly increased for S75&K25 and S90&K10, but they were decreased with an average increase in BTE by 3.84% for S50&K50 fuel when compared to D2. Eventually, it was concluded that high percentages of safflower oil biodiesel can be a potential

  7. Low NO sub x heavy fuel combustor concept program. Phase 1A: Combustion technology generation coal gas fuels

    Science.gov (United States)

    Sherlock, T. P.

    1982-01-01

    Combustion tests of two scaled burners using actual coal gas from a 25 ton/day fluidized bed coal gasifier are described. The two combustor configurations studied were a ceramic lined, staged rich/lean burner and an integral, all metal multiannual swirl burner (MASB). The tests were conducted over a range of temperature and pressures representative of current industrial combustion turbine inlet conditions. Tests on the rich lean burner were conducted at three levels of product gas heating values: 104, 197 and 254 btu/scf. Corresponding levels of NOx emissions were 5, 20 and 70 ppmv. Nitrogen was added to the fuel in the form of ammonia, and conversion efficiencies of fuel nitrogen to NOx were on the order of 4 percent to 12 percent, which is somewhat lower than the 14 percent to 18 percent conversion efficiency when src-2 liquid fuel was used. The MASB was tested only on medium btu gas (220 to 270 btu/scf), and produced approximately 80 ppmv NOx at rated engine conditions. Both burners operated similarly on actual coal gas and erbs fuel, and all heating values tested can be successfully burned in current machines.

  8. Evaluation of the Digestibility of Attached and Suspended Growth Sludge in an Aerobic Digester for a Small Community

    OpenAIRE

    Shohreh Azizi; Ilunga Kamika; Memory Tekere

    2018-01-01

    The aerobic sludge digestion process for waste sludge generated from suspended biomass (i.e., activated sludge process, ASP) and attached biomass (i.e., moving bed bioreactor, MBBR and modified packed bed biofilm, PBBR) reactors in a residential complex were analyzed. The rate of digestion with respect to different sludge characteristics generated through these various treatment processes were examined; the results revealed that waste sludge from ASP took 16 days to achieve complete digestion...

  9. Submersible microbial fuel cell for electricity production from sewage sludge

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Olias, Lola Gonzalez; Kongjan, Prawit

    2011-01-01

    A submersible microbial fuel cell (SMFC) was utilized to treat sewage sludge and simultaneously generate electricity. Stable power generation (145± 5 mW/m2, 470 Ω) was produced continuously from raw sewage sludge for 5.5 days. The maximum power density reached 190±5 mW/m2. The corresponding total...... system to treat sewage sludge and simultaneously recover energy....... chemical oxygen demand (TCOD) removal efficiency was 78.1±0.2% with initial TCOD of 49.7 g/L. The power generation of SMFC was depended on the sludge concentration, while dilution of the raw sludge resulted in higher power density. The maximum power density was saturated at sludge concentration of 17 g...

  10. Combustion engineering

    CERN Document Server

    Ragland, Kenneth W

    2011-01-01

    Introduction to Combustion Engineering The Nature of Combustion Combustion Emissions Global Climate Change Sustainability World Energy Production Structure of the Book   Section I: Basic Concepts Fuels Gaseous Fuels Liquid Fuels Solid Fuels Problems Thermodynamics of Combustion Review of First Law Concepts Properties of Mixtures Combustion StoichiometryChemical EnergyChemical EquilibriumAdiabatic Flame TemperatureChemical Kinetics of CombustionElementary ReactionsChain ReactionsGlobal ReactionsNitric Oxide KineticsReactions at a Solid SurfaceProblemsReferences  Section II: Combustion of Gaseous and Vaporized FuelsFlamesLaminar Premixed FlamesLaminar Flame TheoryTurbulent Premixed FlamesExplosion LimitsDiffusion FlamesGas-Fired Furnaces and BoilersEnergy Balance and EfficiencyFuel SubstitutionResidential Gas BurnersIndustrial Gas BurnersUtility Gas BurnersLow Swirl Gas BurnersPremixed-Charge Engine CombustionIntroduction to the Spark Ignition EngineEngine EfficiencyOne-Zone Model of Combustion in a Piston-...

  11. Pretreatment of microbial sludges

    Science.gov (United States)

    Rivard, Christopher J.; Nagle, Nicholas J.

    1995-01-01

    Methods are described for pretreating microbial sludges to break cells and disrupt organic matter. One method involves the use of sonication, and another method involves the use of shear forces. The pretreatment of sludge enhances bioconversion of the organic fraction. This allows for efficient dewatering of the sludge and reduces the cost for final disposal of the waste.

  12. Presentation of the project Thermal processes with energy recovery for sludge and special or hazardous waste disposal

    International Nuclear Information System (INIS)

    Mininni, G.; Passino, R.

    2001-01-01

    generation takes place only during combustion. Dried sludge is definitely a very good fuel comparing to coal. Fluid dynamic modelling of the demonstrative fluidized bed furnace has conditions. A proper design of the furnace in relation to the diameter, the position of inlet of primary and secondary air and the sand size can be developed accordingly. For a proper design of a incineration process from the energy point of view, a thermal drying section has to be included. To this purpose the sensible heat of the exhaust gases can be recovered in a boiler downstream the furnace with production of medium pressure steam to be used for drying. The optimal dryness of the sludge before feeding the furnace is the minimum value of solid concentration allowing an autogenous combustion, while the overcome of such value is detrimental both for capital and operating costs [it

  13. Combined process of pyrolyzer/combuster for gas production and power generation; Chugoku ni okeru chukibo hatsuden to toshi gas seizo no tame no fukugo process no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Ooka, I. [The University of Tokushima, Tokushima (Japan); Ma, T.

    1997-10-30

    In China, they are using a lot of coal by direct firing for domestic cooking, space heating and industrial use. Therefore air pollution is the big problem in every cities in winter season. And at moment, they do not have enough infrastructure for supplying energy such as gas and electric power. There is a great need for facilities for supplying gas and electric power from coal in big cities with much less pollution. This paper d a combined process of medium size plant of gas production and power generation by using fluidized circulation bed pyrolizer and combuster, to contribute to the energy supply which greatly reduces air and water polution and coal consumption. 1 ref., 1 fig., 3 tabs.

  14. Sustainable sludge management in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, B.; Barrios, J.A.; Mendez, J.M.; Diaz, J.

    2003-07-01

    Worldwide, unsanitary conditions are responsible of more than three million deaths annually. One of the reasons is the low level of sanitation in developing countries. Particularly, sludge from these regions has a high parasite concentration and low heavy metal content even though the available information is limited. Different issues needed to achieve a sustainable sludge management in developing nations are analysed. Based on this analysis some conclusions arise: sludge management plays an important role in sanitation programs by helping reduce health problems and associated risks; investments in sanitation should consider sludge management within the overall projects; the main restriction for reusing sludge is the high microbial concentration, which requires a science-based decision of the treatment process, while heavy metals are generally low; the adequate sludge management needs the commitment of those sectors involved in the development and enforcement of the regulations as well as those that are directly related to its generation, treatment, reuse or disposal; current regulations have followed different approaches, based mainly on local conditions, but they favour sludge reuse to fight problems like soil degradation, reduced crop production, and the increased use of inorganic fertilizers. This paper summarises an overview of theses issues. (author)

  15. Evaluation of selected sewage sludge gasification technological parameters

    Science.gov (United States)

    Gałko, Grzegorz; Król, Danuta

    2018-02-01

    Evaluation of selected sewage sludge gasification technological parameters was shown in this paper. Degree of carbon conducted in combustible substance and syngas efficiency (technological readiness coefficient) in accordance with equations were calculated. Enthalpy of individual compounds formation and energy balance were calculated in accordance with rule of Hess.

  16. The biodrying concept: an innovative technology creating energy from sewage sludge.

    Science.gov (United States)

    Winkler, M-K H; Bennenbroek, M H; Horstink, F H; van Loosdrecht, M C M; van de Pol, G-J

    2013-11-01

    A full-scale biodrying installation was treating 150 kton (wet weight) of dewatered waste activated sludge per year. The waste was treated at thermophilic conditions (65-75 °C) in a 2-step forced aeration process reducing the total wet sludge weight by 73%. The final product had a high caloric value (7700-10,400 (kJ/kg)), allowing a combustion for energy generation in external facilities. The resulting product met the European microbial and heavy metal quality standards needed for an application as organic fertilizer. The facility used <0.5 MW of electricity and recovered 9.3 MW from biologically produced heat, which was internally used for the heating of office buildings. Produced ammonia, originating from the microbial conversion of organic matter, was recovered from the ventilated air in an acid gas scrubber as an ammonium sulphate solution 40% (w/w) (7.3 kton/year) and was sold as substitute for artificial fertilizers. The sustainability of this process is discussed relative to other sludge handling processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Screw pyrolysis technology for sewage sludge treatment.

    Science.gov (United States)

    Tomasi Morgano, Marco; Leibold, Hans; Richter, Frank; Stapf, Dieter; Seifert, Helmut

    2018-03-01

    Sewage sludge quantities have grown continuously since the introduction of the European Directive (UWWTD 91/271/EEC) relating to the treatment of urban wastewater. In the present, most of the sewage sludge is combusted in single fuels incineration plants or is co-fired in waste incineration or coal power plants. The combustion of sewage sludge is a proven technology. Other treatments, such as fluidized bed gasification, were successfully adopted to produce suitable syngas for power production. Besides, the number of large wastewater treatment plants is relatively small compared to the local rural ones. Moreover, alternative technologies are arising with the main target of nutrients recovery, with a special focus on phosphorus. The aforementioned issues, i.e. the small scale (below 1MW) and the nutrients recovery, suggest that pyrolysis in screw reactors may become an attractive alternative technology for sewage sludge conversion, recovery and recycling. In this work, about 100kg of dried sewage sludge from a plant in Germany were processed at the newly developed STYX Reactor, at KIT. The reactor combines the advantages of screw reactors with the high temperature filtration, in order to produce particle and ash free vapors and condensates, respectively. Experiments were carried out at temperatures between 350°C and 500°C. The yield of the char decreased from 66.7wt.% to 53.0wt.%. The same trend was obtained for the energy yield, while the maximum pyrolysis oil yield of 13.4wt.% was obtained at 500°C. Besides mercury, the metals and the other minerals were completely retained in the char. Nitrogen and sulfur migrated from the solid to the condensate and to the gas, respectively. Based on the energy balance, a new concept for the decentral production of char as well as heat and power in an externally fired micro gas turbine showed a cogeneration efficiency up to about 40%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Rule-based programming and strategies for automated generation of detailed kinetic models for gas phase combustion of polycyclic hydrocarbon molecules; Programmation par regles et strategies pour la generation automatique de mecanismes de combustion d'hydrocarbures polycycliques

    Energy Technology Data Exchange (ETDEWEB)

    Ibanescu, L.

    2004-06-15

    The primary objective of this thesis is to explore the approach of using rule-based systems and strategies, for a complex problem of chemical kinetic: the automated generation of reaction mechanisms. The chemical reactions are naturally expressed as conditional rewriting rules. The control of the chemical reactions chaining is easy to describe using a strategies language, such as the one of the ELAN system, developed in the Protheo team. The thesis presents the basic concepts of the chemical kinetics, the chemical and computational problems related to the conception and validation of a reaction mechanism, and gives a general structure for the generator of reaction mechanisms called GasEI. Our research focuses on the primary mechanism generator. We give solutions for encoding the chemical species, the reactions and their chaining, and we present the prototype developed in ELAN. The representation of the chemical species uses the notion of molecular graphs, encoded by a term structure called GasEI terms. The chemical reactions are expressed by rewriting rules on molecular graphs, encoded by a set of conditional rewriting rules on GasEI terms. The strategies language of the ELAN system is used to express the reactions chaining in the primary mechanism generator. This approach is illustrated by coding ten generic reactions of the oxidizing pyrolysis. Qualitative chemical validations of the prototype show that our approach gives, for acyclic molecules, the same results as the existing mechanism generators, and for polycyclic molecules produces original results.

  19. Combustion noise analysis of partially premixed combustion concept using gasoline fuel in a 2-stroke engine

    OpenAIRE

    Broatch Jacobi, Jaime Alberto; Margot , Xandra; Novella Rosa, Ricardo; Gómez-Soriano, Josep

    2016-01-01

    In the last decade, different advanced combustion concepts based on generating totally or partially premixed conditions have been investigated in CI (compression ignition) engines with the aim of achieving lower NOx (nitrous oxides) and soot emissions. Most of the drawbacks inherent to this type of combustions, such as the combustion phasing control or combustion stability, can be mitigated by combining the PPC (Partially Premixed Combustion) concept fueled by gasoline and a small...

  20. Technical notes for the conceptual design for an atmospheric fluidized-bed direct combustion power generating plant. [570 MWe plant

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-04-01

    The design, arrangement, thermodynamics, and economics of a 578 MW(e) (nominal gross) electric power generating plant equipped with a Foster Wheeler Energy Corporation (FWEC) atmospheric fluidized bed (AFB) boiler are described. Information is included on capital and operating costs, process systems, electrical systems, control and instrumentation, and environmental systems. This document represents a portion of an overall report describing the conceptual designs of two atmospheric fluidized bed boilers and balance of plants for the generation of electric power and the analysis and comparison of these conceptual designs to a conventional pulverized coal-fired electric power generation plant equipped with a wet limestone flue gas desulfurization system.

  1. Technical notes for the conceptual design for an atmospheric fluidized-bed direct combustion power generating plant. [570 MWe plant

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-04-01

    The design, arrangement, thermodynamics, and economics of a 592 MW(e) (nominal gross) electric power generating plant equipped with a Babcock and Wilcox Company (B and W) atmospheric fluidized bed (AFB) boiler are described. Information is included on capital and operating costs, process systems, electrical systems, control and instrumentation, and environmental systems. This document represents a portion of an overall report describing the conceptual designs of two atmospheric fluidized bed boilers and balance of plants for the generation of electric power and the analysis and comparison of these conceptual designs to a conventional pulverized coal-fired electric power generation plant equipped with a wet limestone flue gas desulfurization system.

  2. Coal Combustion Wastes Reuse in Low Energy Artificial Aggregates Manufacturing

    OpenAIRE

    Ferone, Claudio; Colangelo, Francesco; Messina, Francesco; Iucolano, Fabio; Liguori, Barbara; Cioffi, Raffaele

    2013-01-01

    Sustainable building material design relies mostly on energy saving processes, decrease of raw materials consumption, and increase of waste and by-products recycling. Natural and lightweight artificial aggregates production implies relevant environmental impact. This paper addresses both the issues of residues recycling and energy optimization. Particularly, three coal combustion wastes (Weathered Fly Ash, WFA; Wastewater Treatment Sludge, WTS; Desulfurization Device Sludge, DDS) supplied by ...

  3. The performance characteristics of a hydrogen-fuelled free piston internal combustion engine and linear generator system

    OpenAIRE

    Youngmin Woo; Youngjae Lee; Yonggyun Lee

    2009-01-01

    A power generation system that utilizes a hydrogen-fuelled free piston engine (FPICE) and a linear generator are under development. A FPICE gives power output more efficiently compared with conventional reciprocating piston engines, because it utilizes many benefits such as low friction loss and inherently variable compression ratio apart from the low emission of hazardous exhaust gases. In addition, if hydrogen fuel is used in an FPICE, it would be possible to make the exhaust emission level...

  4. Ash and heavy metals in fluidized-bed combustion of wood wastes; Tuhka ja raskasmetallit puuperaeisen jaetteen kerrosleijupoltossa

    Energy Technology Data Exchange (ETDEWEB)

    Kaessi, T.; Aittoniemi, P. [IVO Power Engineering, Vantaa (Finland); Kauppinen, E.; Latva-Somppi, J.; Kurkela, J. [VTT Chemical Technology, Espoo (Finland); Partanen, J. [IVO Technology Centre, Vantaa (Finland)

    1997-10-01

    Ash formation and deposition mechanisms during co-combustion of pulp mill sludge and bark in industrial bubbling fluidized bed (BFB) combustor have been studied. Similar fuels were used in a bench-scale BFB for co-combustion of sludge and bark pellets and comparative studies with separate combustion of these fuels. Results indicated that in industrial scale unit significant fraction of ash had vaporization. About 14 mass-% of the total fly ash was found in the particle size below 0.2 {mu}m. The vaporized species consisted of potassium (K), sulfur (S), chlorine (Cl) and also of minor quantities of sodium (Na). In the benchscale similar vaporization fractions during co-combustion were measured, about 11 mass-%. During the combustion of bark this ratio, about 20 mass-%, was higher than during sludge combustion. The vaporized ash fraction was in the case of dried sludge combustion about 7 mass-%, but with wet sludge the vaporization rate was remarkably lower, about 1-2 mass-%. An increase in the bed temperature increased also ash vaporization. Test run period without combustion at elevated temperatures produced very low quantities of vaporized ash. The vaporized species in bench-scale test during bark pellet combustion were K, S and Cl, for sludge combustion also Na was clearly detected. No condensation of the vaporized species in bed area or furnace walls was observed. Bed defluidization was studied in the bench-scale unit. During bark pellet combustion the bed-agglomeration proceeded via small ash particle, below 2 {mu}m, coating on sand particle surface and consequent bonding between the ash layers. In the case of sludge combustion the accumulation of large ash particles and sintering of these porous agglomerates was observed to cause bed coarsening and defluidization. (orig.)

  5. Biogas of manure and sludge

    Science.gov (United States)

    Kraemer, F.; Gundermann, J.; Kofoed, E.; Nielsen, J.

    1981-01-01

    Biogas production from farmyard manures and sewage sludges is based on anaerobic processes (methane-bacteria) and aerobic processes (fermentative bacteria). Biogas product has high calorific value and a number of small, pilot-scale and full-scale municipal systems of biogas production is described inclusive technological solutions and cost-benefit analysis. Experience of electric power generators fueled by biogas is evaluated from the view point of competitiveness with other fuels.

  6. Pressure drop-flow rate curves for single-phase steam in Combustion Engineering type steam generator U-tubes during severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Fynan, Douglas A.; Ahn, Kwang-Il, E-mail: kiahn@kaeri.re.kr

    2016-12-15

    Highlights: • Pressure drop-flow rate curves for superheated steam in U-tubes were generated. • Forward flow of hot steam is favored in the longer and taller U-tubes. • Reverse flow of cold steam is favored in short U-tubes. • Steam generator U-tube bundle geometry and tube diameter are important. • Need for correlation development for natural convention heat transfer coefficient. - Abstract: Characteristic pressure drop-flow rate curves are generated for all row numbers of the OPR1000 steam generators (SGs), representative of Combustion Engineering (CE) type SGs featuring square bend U-tubes. The pressure drop-flow rate curves are applicable to severe accident natural circulations of single-phase superheated steam during high pressure station blackout sequences with failed auxiliary feedwater and dry secondary side which are closely related to the thermally induced steam generator tube rupture event. The pressure drop-flow rate curves which determine the recirculation rate through the SG tubes are dependent on the tube bundle geometry and hydraulic diameter of the tubes. The larger CE type SGs have greater variation of tube length and height as a function of row number with forward flow of steam favored in the longer and taller high row number tubes and reverse flow favored in the short low row number tubes. Friction loss, natural convection heat transfer coefficients, and temperature differentials from the primary to secondary side are dominant parameters affecting the recirculation rate. The need for correlation development for natural convection heat transfer coefficients for external flow over tube bundles currently not modeled in system codes is discussed.

  7. H{sub 2}S and CO{sub 2} filtration of biogas used in internal combustion engines for power generation

    Energy Technology Data Exchange (ETDEWEB)

    Huertas, Jose Ignacio; Izquierdo, Sebastian [Instituto Tecnologico y de Estudios Superiores de Monterrey, (Mexico)]. E-mail: jhuertas@itesm.mx

    2009-09-15

    Currently, there is an increasing interest in connecting thousands of small electrical plants powered by renewable energy sources to national electrical grids. The use of biogas as fuel for internal combustion engines connected to an electric generator is emerging as one of the most attractive alternatives because of its very low cost benefit ratio and very high positive impact on the environment. However, the use of biogas to generate electricity has been limited by its high content of H{sub 2}S ({approx}3500 ppm) and CO{sub 2} ({approx}40%). CO{sub 2} presence reduces the energetic density of the fuel and therefore the power output of the system. The high content of H{sub 2}S corrodes important components of the engine like the combustion chamber, bronze gears and the exhaust system. This work aims to design and manufacture a low-cost industrial filter for this application. Among the different available methodologies, CaO, NaOH and amines where selected as the most appropriate for a typical farm application of 100 kW electric generations. Since there is not reported data for the H{sub 2}S absorbing capacity of these substances, it was proposed to measure it by means of a bubbler. It is an experimental set up where the gas stream passes through a fixed amount of the absorbing substance until it becomes saturated. The absorbing capacity is determined as the amount of substance being trapped divided by the mass of the absorbing substance being used. Results showed an absorbing capacity of 2.8, 41.4 and 124.8 g of H{sub 2}S per Kg of NaOH, CaO and monoethanolamine respectively. A gas absorbing system of amines was designed and manufactured for H{sub 2}S and CO{sub 2} biogas filtration. Three different types of amines were evaluated: Monoethanolamine, Diethanolamine, and methyldiethanolamine. Results show that all the amines require a ratio of amines to biogas flow of 0.7 to obtain a 95% of H{sub 2}S filtering efficiency. This data represent only a 30% of H{sub 2}S

  8. [Effects of ultrasonic pretreatment on drying characteristics of sewage sludge].

    Science.gov (United States)

    Li, Run-Dong; Yang, Yu-Ting; Li, Yan-Long; Niu, Hui-Chang; Wei, Li-Hong; Sun, Yang; Ke, Xin

    2009-11-01

    The high water content of sewage sludge has engendered many inconveniences to its treatment and disposal. While ultrasonic takes on unique advantages on the sludge drying because of its high ultrasonic power, mighty penetrating capability and the ability of causing cavitations. Thus this research studies the characteristics influences of ultrasonic bring to the sludge drying and effects of the exposure time, ultrasonic generator power, temperatures of ultrasonic and drying temperature on the drying characteristics of dewatered sludge. Results indicate that ultrasonic pretreatment could speed up evaporation of the free water in sludge surface and help to end the drying stage with constant speed. In addition, ultrasonic treatment can effectively improve the sludge drying efficiency which could be more evident with the rise of the ultrasonic power (100-250 W), ultrasonic temperature and drying temperature. If dried under low temperature such as 105 degrees C, sludge will have premium drying characteristics when radiated under ultrasound for a shorter time such as 3 min. In the end, the ultrasonic treatment is expected to be an effective way to the low-cost sludge drying and also be an important reference to the optimization of the sludge drying process because of its effects on the increase of sludge drying efficiency.

  9. Fiscal year 1994 1/25-scale sludge mobilization testing

    International Nuclear Information System (INIS)

    Powell, M.R.; Gates, C.M.; Hymas, C.R.; Sprecher, M.A.; Morter, N.J.

    1995-07-01

    There are 28 one-million-gallon double-shell radioactive waste tanks on the Hanford Reservation in southeastern Washington State. The waste in these tanks was generated during processing of nuclear materials. Solids-laden slurries were placed into many of the tanks. Over time, the waste solids have settled to form a layer of sludge in the bottom of these tanks. The sludge layer thickness varies from tank to tank with some having only a few centimeters or no sludge up to some tanks which have about 4.5 m (15 ft) of sludge. It is planned that the waste will be removed from these tanks as part of the overall Hanford site cleanup efforts. Jet mixer pumps are to be placed into the tanks to stir up (mobilize) the sludge and form a uniform slurry suitable for pumping to downstream processing facilities. These mixer pumps use powerful jets of tank fluid directed horizontally out of two, diametrically opposed nozzles near the tank bottom. These fluid jets impinge upon the sludge and stir it up. The amount of sludge mobilized by the mixer pump jets depends not only on the jet properties, but also on the ability of the sludge to resist the jets. It is the goal of the work described in this document to develop the ability to predict how much sludge will be mobilized by the mixer pumps based on the size and velocity of the mixer pump jets and the physical and chemical properties of the tank sludge

  10. Availability of uranium present in the sludge generated at two stations of potable water treatment; Disponibilidad del uranio presente en el fango generado en dos estaciones de tratamiento de agua potable

    Energy Technology Data Exchange (ETDEWEB)

    Munoz-Serrano, A.; Baeza, A.; Salas, A.; Guillen, J.

    2013-07-01

    During the treatment is carried out in a Station Potable Water Treatment Plant sludge enriched are produced in components that have been removed from the water. The concentration and availability of radionuclides accumulated in a sludge during coagulation-flocculation will condition possible later use, so it is essential to carry out the characterization of sludge and its chemical speciation. (Author)

  11. Microbial enhanced separation of oil from a petroleum refinery sludge.

    Science.gov (United States)

    Joseph, P J; Joseph, Ammini

    2009-01-15

    Petroleum refineries around the world have adopted different technological options to manage the solid wastes generated during the refining process and stocking of crude oil. These include physical, chemical and biological treatment methods. In this investigation bacterial mediated oil separation is effected. Two strains of Bacillus were isolated from petroleum-contaminated soils, and inoculated into slurry of sludge, and sludge-sand combinations. The bacteria could effect the separation of oil so as to form a floating scum within 48h with an efficiency of 97% at < or =5% level of sludge in the sludge-sand mixture. The activity was traced to the production of biosurfactants by bacteria.

  12. Effect of a static magnetic field on activated sludge community.

    Science.gov (United States)

    Drzewicki, Adam; Dębowski, Marcin; Zieliński, Marcin

    2017-10-01

    The aim of this study was to determine the effect of a static magnetic field (SMF) on the composition of activated sludge biocenosis. The experiment was carried out in two parallel bench scale Sequencing Batch Reactors (SBRs). Both SBRs were treated with dairy wastewater. The activated sludge in the first SBR was exposed to an SMF via the induction of a 0.6 T magnetic field generated by four magnetic liquid activators. The second reactor (control reactor) was operated at the same operational parameters but the activated sludge was not exposed to the SMF. The mean length of the bacterium Eikelboom Type 0092 was lower in the SMF-exposed reactor than in the control reactor. Different activated sludge morphologies in SBRs were reflected in the values of the sludge volume index and sludge biotic index calculated on the basis of the microfauna composition.

  13. Research of combustion in older generation spark-ignition engines in the condition of use leaded and unleaded petrol

    OpenAIRE

    Bulatović Željko M.; Rakić Slavko N.; Knežević Dragan M.; Tomić Miroljub V.; Bojer Ljubiša M.; Radić Dragoslav B.; Jerkin Goran L.

    2014-01-01

    This paper analyzes the potential problems in the exploitation of the older generation of spark-ignition engines with higher octane number of petrol (unleaded petrol BMB 95) than required (leaded petrol MB 86). Within the experimental tests on two different engines (STEYR-PUCH model 712 and GAZ 41) by applying piezoelectric pressure sensors integrated with the engine spark plugs, acceleration sensors (accelerometers) and special electronic block connected w...

  14. Recycling of stone cutting sludge in formulations of bricks and terrazzo tiles.

    Science.gov (United States)

    Al-Zboon, Kamel; Tahat, Montasser; Abu-Hamatteh, Ziad S H; Al-Harahsheh, Mohammad S

    2010-06-01

    This study examines the possibility for enhancing the use of stone cutting sludge waste in the production of building bricks and terrazzo tiles, which would reduce both the environmental impact and the production costs. Stone cutting wastes in the form of sludge is currently generated at several factories in Jordan. At the Samara factory, incorporation of the sludge in the batch formulations of bricks and terrazzo tiles was examined. The physicochemical and mineralogical characteristics of the sludge were analyzed to identify the major components. Results indicated that the sludge generated from stone cutting could be used in producing concrete bricks. Mixtures of aggregates with added amounts of sludge were used successfully to produce non-load bearing bricks. Sludge was also used to produce terrazzo tiles and the results indicate that the transverse strength, water absorption and tile measurements, for all the taken samples, comply with Jordanian standards. The transverse strength decreased while water absorption increased as the sludge ratio increased.

  15. Disposal of sewage sludge. Rotary kiln plants and energetic utilization of sewage sludge; Klaerschlammentsorgung. Drehrohranlagen in der Trocknung und energetischen Nutzung von Klaerschlamm

    Energy Technology Data Exchange (ETDEWEB)

    Hormes, Franz [Visser und Smit Hanab GmbH, Kaarst (Germany). Rotary Kilns

    2013-03-01

    The author of the contribution under consideration reports on rotary kiln plants in the disposal of sewage sludge. The examples give an insight into the systems engineering for the thermal treatment of sewage sludge, for the minimization or full thermal utilization. The examples show that there exists any specific solution. The process selection depends on the legal requirements and the framework conditions in dependence from the site and infrastructure. Generally, the following statements are valid: (a) The co-combustion is cheaper than every mono-combustion; (b) The costs for the transport of wet sludge often are more favourable than the costs of drying; (c) Plants for low capacities are specifically expensive. The following criteria become more important: (a) energy costs, recycling of energy; (b) recycling of phosphorus from sewage sludge; (c) Reduction of the input of heavy metals in order to comply with the fertilizer ordinance.

  16. Sludge recovery apparatus

    International Nuclear Information System (INIS)

    Marmo, A.R.

    1979-01-01

    An improved design of a sludge recovery apparatus used in the fabrication of nuclear fuel is described. This apparatus provides for automatic separation of sludge from the grinder coolant, drying of the sludge into a flowable powder and transfer of the dry powder to a salvage container. It can be constructed to comply with criticality-safe-geometry requirements and to obviate need for operating personnel in its immediate vicinity. (UK)

  17. Persistent free radicals, heavy metals and PAHs generated in particulate soot emissions and residue ash from controlled combustion of common types of plastic

    International Nuclear Information System (INIS)

    Valavanidis, Athanasios; Iliopoulos, Nikiforos; Gotsis, George; Fiotakis, Konstantinos

    2008-01-01

    The production and use of polymeric materials worldwide has reached levels of 150 million tonnes per year, and the majority of plastic materials are discarded in waste landfills where are burned generating toxic emissions. In the present study we conducted laboratory experiments for batch combustion/burning of commercial polymeric materials, simulating conditions of open fire combustion, with the purpose to analyze their emissions for chemical characteristics of toxicological importance. We used common types of plastic materials: poly(vinyl chloride) (PVC), low and high density poly(ethylene) (LDPE, HDPE), poly(styrene) (PS), poly(propylene) (PP) and poly(ethylene terephthalate) (PET). Samples of particulate smoke (soot) collected on filters and residue solid ash produced by controlled burning conditions at 600-750 deg. C are used for analysis. Emissions of particulate matter, persistent free radicals embedded in the carbonaceous polymeric matrix, heavy metals, other elements and PAHs were determined in both types of samples. Results showed that all plastics burned easily generating charred residue solid ash and black airborne particulate smoke. Persistent carbon- and oxygen-centered radicals, known for their toxic effects in inhalable airborne particles, were detected in both particulate smoke emissions and residue solid ash. Concentrations of heavy metals and other elements (determined by Inductively Coupled Plasma Emission Spectrometry, ICP, method) were measured in the airborne soot and residue ash. Toxic heavy metals, such as Pb, Zn, Cr, Ni, and Cd were relatively at were found at low concentrations. High concentrations were found for some lithophilic elements, such as Na, Ca, Mg, Si and Al in particulate soot and residue solid ash. Measurements of PAHs showed that low molecular weight PAHs were at higher concentrations in the airborne particulate soot than in the residue solid ash for all types of plastic. Higher-ringed PAHs were detected at higher

  18. Persistent free radicals, heavy metals and PAHs generated in particulate soot emissions and residue ash from controlled combustion of common types of plastic.

    Science.gov (United States)

    Valavanidis, Athanasios; Iliopoulos, Nikiforos; Gotsis, George; Fiotakis, Konstantinos

    2008-08-15

    The production and use of polymeric materials worldwide has reached levels of 150 million tonnes per year, and the majority of plastic materials are discarded in waste landfills where are burned generating toxic emissions. In the present study we conducted laboratory experiments for batch combustion/burning of commercial polymeric materials, simulating conditions of open fire combustion, with the purpose to analyze their emissions for chemical characteristics of toxicological importance. We used common types of plastic materials: poly(vinyl chloride) (PVC), low and high density poly(ethylene) (LDPE, HDPE), poly(styrene) (PS), poly(propylene) (PP) and poly(ethylene terephthalate) (PET). Samples of particulate smoke (soot) collected on filters and residue solid ash produced by controlled burning conditions at 600-750 degrees C are used for analysis. Emissions of particulate matter, persistent free radicals embedded in the carbonaceous polymeric matrix, heavy metals, other elements and PAHs were determined in both types of samples. Results showed that all plastics burned easily generating charred residue solid ash and black airborne particulate smoke. Persistent carbon- and oxygen-centered radicals, known for their toxic effects in inhalable airborne particles, were detected in both particulate smoke emissions and residue solid ash. Concentrations of heavy metals and other elements (determined by Inductively Coupled Plasma Emission Spectrometry, ICP, method) were measured in the airborne soot and residue ash. Toxic heavy metals, such as Pb, Zn, Cr, Ni, and Cd were relatively at were found at low concentrations. High concentrations were found for some lithophilic elements, such as Na, Ca, Mg, Si and Al in particulate soot and residue solid ash. Measurements of PAHs showed that low molecular weight PAHs were at higher concentrations in the airborne particulate soot than in the residue solid ash for all types of plastic. Higher-ringed PAHs were detected at higher

  19. Fluid-bed combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G.; Schoebotham, N.

    1981-02-01

    In Energy Equipment Company's two-stage fluidized bed system, partial combustion in a fluidized bed is followed by burn-off of the generated gases above the bed. The system can be retrofitted to existing boilers, and can burn small, high ash coal efficiently. It has advantages when used as a hot gas generator for process drying. Tests on a boiler at a Cadbury Schweppes plant are reported.

  20. Sludge storage lagoon biogas recovery and use

    Energy Technology Data Exchange (ETDEWEB)

    Muller, D.; Norville, C. (Memphis and Shelby County Div. of Planning and Development, TN (United States))

    1991-07-01

    The City of Memphis has two wastewater treatment plants. The SWTP employs two large anaerobic digestion sludge lagoons as part of the overall sludge treatment system. Although these lagoons are effective in concentrating and digesting sludge, they can generate offensive odors. The SWTP uses aerobic digesters to partially stabilize the sludge and help reduce objectionable odors before it enters the lagoons. The anaerobic digestion of sludge in the lagoons results in the dispersion of a large quantity of biogas into the atmosphere. The City realized that if the lagoons could be covered, the odor problem could be resolved, and at the same, time, biogas could be recovered and utilized as a source of energy. In 1987, the City commissioned ADI International to conduct a feasibility study to evaluate alternative methods of covering the lagoons and recovering and utilizing the biogas. The study recommended that the project be developed in two phases: (1) recovery of the biogas and (2) utilization of the biogas. Phase 1 consists of covering the two lagoons with an insulated membrane to control odor and temperature and collect the biogas. Phase 1 was found to be economically feasible and offered a unique opportunity for the City to save substantial operating costs at the treatment facility. The Memphis biogas recovery project is the only application in the world where a membrane cover has been used on a municipal wastewater sludge lagoon. It is also the largest lagoon cover system in the world.

  1. SLUDGE BATCH 6 PHASE II FLOWSHEET SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, D.; Best, D.

    2010-03-30

    Two Sludge Receipt and Adjustment Tank (SRAT) runs were used to demonstrate that a fairly wide window of acid stoichiometry was available for processing SB6 Phase II flowsheet simulant (Tank 40 simulant) while still meeting the dual goals of acceptable nitrate destruction and controlled hydrogen generation. Phase II was an intermediate flowsheet study for the projected composition of Tank 40 after transfer of SB6/Tank 51 sludge to the heel of SB5. The composition was based on August 2009 projections. A window of about 50% in total acid was found between acceptable nitrite destruction and excessive hydrogen generation.

  2. CO2-free power generation in combined cycles-Integration of post-combustion separation of carbon dioxide in the steam cycle

    International Nuclear Information System (INIS)

    Moeller, Bjoern Fredriksson; Assadi, Mohsen; Potts, Ian

    2006-01-01

    Ever since the release of the Kyoto protocol the demand for CO 2 -free processes have been increasing. One of the most expanding sources of electric power in the industrialised world today is the gas-fired combined cycle, combining high efficiency and low investment cost. In this paper, the integration of a post-combustion CO 2 -separation unit into a combined cycle is studied from a thermodynamic and economic point-of-view. A standard dual-pressure combined cycle is chosen as a reference cycle. It is compared to a dual-pressure combined cycle and a triple-pressure combined cycle with the lowest pressure level producing steam for a CO 2 -separation unit. The steam pressure levels in the different cycles are optimised for maximum efficiency and minimum specific cost, respectively, using genetic algorithms. The efficiency drop due to CO 2 -separation is approximately 8% points, from 54 to 46%. The specific cost of the power plant is expected to increase with almost 100% and the cost of electricity with approximately 30%. In several countries a carbon dioxide tax is already introduced as an incentive for more efficient power cycles and use of fuels with lower content of coal. The result above implies that the level of such a tax would be in the order of 30% of the price of electricity to encourage CO 2 -free power generation

  3. Activated Sludge Rheology

    DEFF Research Database (Denmark)

    Ratkovich, Nicolas Rios; Horn, Willi; Helmus, Frank

    2013-01-01

    Rheological behaviour is an important fluid property that severely impacts its flow behaviour and many aspects related to this. In the case of activated sludge, the apparent viscosity has an influence on e.g. pumping, hydrodynamics, mass transfer rates, sludge-water separation (settling and filtr...

  4. Respirometry in activated sludge

    NARCIS (Netherlands)

    Spanjers, H.

    1993-01-01

    The purpose of the study was (1) to develop a respiration meter capable of continuously measuring, using different procedures, the oxygen uptake rate of activated sludge and (2) to expand knowledge about respiration related characteristics of wastewater and activated sludge.

    A

  5. Anaerobic sludge granulation

    NARCIS (Netherlands)

    Hulshoff Pol, L.W.; Castro Lopes, de S.I.; Lettinga, G.; Lens, P.N.L.

    2004-01-01

    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades
    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades. The initial

  6. Effect of cooling design on the characteristics and performance of thermoelectric generator used for internal combustion engine

    International Nuclear Information System (INIS)

    Du, Qing; Diao, Hai; Niu, Zhiqiang; Zhang, Guobin; Shu, Gequn; Jiao, Kui

    2015-01-01

    Highlights: • A 3-D model of TEG coupled with exhaust and cooling channels is developed. • Effect of cooling type, flow rate, baffler and flow arrangement is investigated. • Flow resistance is large for air cooling, and liquid cooling has high net power. • Flow rate and baffler length need to be moderate for air cooling. • Counter is better than co-flow by keeping temperature difference for all TEGs. - Abstract: By developing a thermoelectric generator (TEG) model coupled with exhaust and cooling channels for an exhaust-based TEG (ETEG) system, the influence of the cooling type, coolant flow rate, length, number and location of bafflers, and flow arrangement are investigated. It is found that the net output power is generally higher with liquid cooling than air cooling. Since a very low velocity of liquid coolant is sufficient for cooling the TEG modules, the flow resistance is negligible, and inserting a baffler, increasing the baffler length or the flow velocity generally improves the performance. However, both the baffler length and flow velocity of air cooling need to be moderate. Placing one baffler in front of a TEG module is sufficient to guide the cooling flow. The performance is generally unaffected by the change of baffler location. By maintaining sufficient temperature difference for all the TEG modules, the counter-flow arrangement leads to higher output power than the co-flow arrangement. Although liquid cooling is more complicated, and extra cooling power may be needed to cool down the circulating coolant, the temperature increment of liquid coolant through cooling channel is insignificant for cooling 20 TEG modules producing about 250 W of power

  7. Selective catalytic reduction of NOx over pyrolyzed sludge char

    International Nuclear Information System (INIS)

    Ko, Jeong Huy; Heo, Hyeon Su; Park, Hye Jin; Bae, Yoon Ju; Kim, Jung Hwan; Cho, Hye Jung; Park, Young Kwon

    2010-01-01

    Full text: In this study, applicability of the activated pyrolyzed sludge char as a De-NO x catalyst was investigated. Sludge chars were generated by the pyrolysis condition, such as temperature, heating rate and reaction time. As pyrolysis temperature increased from 300 to 600 degree Celsius, the specific surface area and porosity of sludge chars were increased but were reduced at 700 degree Celsius, and thereafter were increased at 800 degree Celsius again. However, the pyrolysis heating rate and reaction time had an no large effect on the specific area and porosity of sludge chars. Considering these results, the pyrolysis temperature was the most parameter to affecting the specific area and porosity of sludge chars. In order to enhance the physical characteristics of sludge chars, they were activated by the physical and chemical activation methods with steam and KOH, respectively, and the effects of the activation temperature, moisture concentration and KOH/ char ratio on the physical characteristics of sludge chars were also studied. Chemically activated sludge chars showed the higher NO x removal efficiency than physically ones. Especially, the sludge char activated under the condition of a KOH/ Char ratio 2.0 and temperature 600 degree Celsius exhibited the highest NO x removal efficiency of 84.2% at 250 degree Celsius, which was even higher than 35.6% over a commercial activated carbon. (author)

  8. Combustion testing and heat recovery study: Frank E. Van Lare Wastewater Treatment Plant, Monroe County. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chattopadhyay, A.

    1995-01-01

    The report describes the results of combustion testing work, and analysis of heat recovery and use at the Monroe County Frank E. Van Lare wastwater treatment plant (WWTP). The three multiple-hearth furnaces at the plant process an average of 65 dry tons of dewatered sludge per day. The furnaces use about 12.5 million Btus of natural gas per dry ton of sludge incinerated, or about 300 billion Btus per year. Center shaft and rabble arm cooling air is recirculated to the furnaces as pre-heated combustion air. No other heat from the combustion process is recovered for use in the plant. The project had four objectives: to record and analyze sludge management operations data and sludge incinerator combustion data; to ascertain instrumentation and control needs; to calculate heat balances for the incineration system; and to determine the feasibility of full waste-heat recovery and utilization, at the Frank E. Van Lare wastewater treatment plant.

  9. Activated sludge model No. 3

    DEFF Research Database (Denmark)

    Gujer, W.; Henze, M.; Mino, T.

    1999-01-01

    The Activated Sludge Model No. 3 (ASM3) can predict oxygen consumption, sludge production, nitrification and denitrification of activated sludge systems. It relates to the Activated Sludge Model No. 1 (ASM1) and corrects for some defects of ASM I. In addition to ASM1, ASM3 includes storage...

  10. Health effects engineering of coal and biomass combustion particulates: influence of zinc, sulfur and process changes on potential lung injury from inhaled ash

    Energy Technology Data Exchange (ETDEWEB)

    Art Fernandez; Jost O.L. Wendt; Mark L. Witten [University of Arizona, Tucson, AZ (United States). Department of Chemical and Environmental Engineering

    2003-07-01

    This paper is concerned with health effects of the ash aerosol formed from the co-combustion of municipal sewage sludge with pulverized coal. To study, and mitigate, possible lung injury caused by inhalation of these ash particles, it is useful to employ 'Health Effects Engineering', which attempts to build connections between mechanisms that form particulates during the combustion process and mechanisms that cause these ill health effects. Initial results showed that inhalation of ash from the co-combustion of municipal sewage sludge (MSS) and pulverized coal caused much greater lung damage in mice, as measured by lung permeability increase, than that of coal ash, or MSS ash, alone. MSS contains substantial quantities of zinc but little sulfur, while coal contains sulfur but little zinc. Therefore, systematic experiments were conducted to determine the health effects of combustion generated zinc particles and zinc plus sulfur particles. Zinc without sulfur led to 'normal' behavior as far as lung permeability was concerned. Zinc with sulfur added led to the 'abnormal' behavior noted also in the coal +MSS experiments. Therefore the bad actor was identified to be zinc together with sulfur, and that was why the co-combustion of coal and MSS caused greater lung injury than the combustion of either fuel alone. Health effects engineering can also be employed to diminish this health risk caused by burning fuels containing both zinc and sulfur. Injection of a kaolinite sorbent downstream of the flame, but above the Zn dew point, can sequester the Zn, and react to form a new species which was shown to be relatively benign. 18 refs., 9 figs., 1 tab.

  11. Sludge minimization technologies - an overview

    Energy Technology Data Exchange (ETDEWEB)

    Oedegaard, Hallvard

    2003-07-01

    The management of wastewater sludge from wastewater treatment plants represents one of the major challenges in wastewater treatment today. The cost of the sludge treatment amounts to more that the cost of the liquid in many cases. Therefore the focus on and interest in sludge minimization is steadily increasing. In the paper an overview is given for sludge minimization (sludge mass reduction) options. It is demonstrated that sludge minimization may be a result of reduced production of sludge and/or disintegration processes that may take place both in the wastewater treatment stage and in the sludge stage. Various sludge disintegration technologies for sludge minimization are discussed, including mechanical methods (focusing on stirred ball-mill, high-pressure homogenizer, ultrasonic disintegrator), chemical methods (focusing on the use of ozone), physical methods (focusing on thermal and thermal/chemical hydrolysis) and biological methods (focusing on enzymatic processes). (author)

  12. Next generation straw fired boilers for district hearing - improved combustion, reduced emissions and increased efficiency; Optimering af halmfyrede kedler til fjernvarme - bedre forbraending, lavere emission og hoejere virkningsgrad

    Energy Technology Data Exchange (ETDEWEB)

    Videcrantz, G.; Hjuler, K.; Johansen, Lars Peter; Joergensen, Jan

    2007-01-15

    The objective of the project was to provide participating manufacturers with a number of tools for product development within: a) improved combustion quality, b) lower emission, c) improved yield, and d) lower construction costs. Furthermore the aim was to build bridge between the research world and a commercial development department. The project chose to focus on development of one tool with a number of applications, namely CFD (Computational Fluid Dynamics) modelling. The tool was used on three selected areas: 1) NO{sub x} control and reduction, 2) Improved design of combustion chamber and air supply, and 3) Lowered oxygen percent. The main result from the project is a complete CFD and combustion model of a straw combustion plant. The model can be used for testing of changes in design as well as in operation and can be adapted for different plant types. (BA)

  13. Deep Sludge Gas Release Event Analytical Evaluation

    International Nuclear Information System (INIS)

    Sams, Terry L.

    2013-01-01

    Long Abstract. Full Text. The purpose of the Deep Sludge Gas Release Event Analytical Evaluation (DSGRE-AE) is to evaluate the postulated hypothesis that a hydrogen GRE may occur in Hanford tanks containing waste sludges at levels greater than previously experienced. There is a need to understand gas retention and release hazards in sludge beds which are 200 -300 inches deep. These sludge beds are deeper than historical Hanford sludge waste beds, and are created when waste is retrieved from older single-shell tanks (SST) and transferred to newer double-shell tanks (DST).Retrieval of waste from SSTs reduces the risk to the environment from leakage or potential leakage of waste into the ground from these tanks. However, the possibility of an energetic event (flammable gas accident) in the retrieval receiver DST is worse than slow leakage. Lines of inquiry, therefore, are (1) can sludge waste be stored safely in deep beds; (2) can gas release events (GRE) be prevented by periodically degassing the sludge (e.g., mixer pump); or (3) does the retrieval strategy need to be altered to limit sludge bed height by retrieving into additional DSTs? The scope of this effort is to provide expert advice on whether or not to move forward with the generation of deep beds of sludge through retrieval of C-Farm tanks. Evaluation of possible mitigation methods (e.g., using mixer pumps to release gas, retrieving into an additional DST) are being evaluated by a second team and are not discussed in this report. While available data and engineering judgment indicate that increased gas retention (retained gas fraction) in DST sludge at depths resulting from the completion of SST 241-C Tank Farm retrievals is not expected and, even if gas releases were to occur, they would be small and local, a positive USQ was declared (Occurrence Report EM-RP--WRPS-TANKFARM-2012-0014, 'Potential Exists for a Large Spontaneous Gas Release Event in Deep Settled Waste Sludge'). The purpose of this technical

  14. Hydrogen combustion in aqueous foams

    International Nuclear Information System (INIS)

    Baer, M.R.; Griffiths, S.K.; Shepherd, J.E.

    1982-01-01

    Water fogs are recognized as an effective means to mitigate the effects of large-scale hydrogen combustion that might accompany some reactor loss-of-coolant reactor accidents. Fogs of sufficiently high density to produce large beneficial effects may, however, be difficult to generate and maintain. An alternate method of suspending the desired mass of water is via high expansion-ratio aqueous foams. Because the foam would be generated using the combustible gaseous contents of the containment vessel, combustion occurs inside the foam cells. Although foams generated with inert gas have been well studied for use in fire fighting, little is known about combustion in foams generated with flammable mixtures. To help assess the usefulness of aqueous foams in a mitigation plan, the authors have conducted open tube tests and closed vessel tests of hydrogen/air combustion with and without foam. At low and intermediate hydrogen concentrations, the foam has little effect on the ultimate isochoric pressure rise. Above 15% hydrogen concentration, the foam causes a significant reduction in the pressure rise. The maximum effect occurs at about 28% hydrogen where the peak overpressure is reduced by two and one-half. Despite this overall pressure reduction, the flame speed is increased by up to an order of magnitude for combustion in the foam and strong pressure fluctuations are observed near a hydrogen concentration of 23%

  15. Hydrogen combustion in aqueous foams

    International Nuclear Information System (INIS)

    Baer, M.R.; Griffiths, S.K.; Shepherd, J.E.

    1984-01-01

    Water fogs are recognized as an effective means to mitigate the effects of large-scale hydrogen combustion that might accompany some loss of coolant nuclear reactor accidents. Fogs of sufficiently high density to produce large beneficial effects may, however, be difficult to generate and maintain. An alternate method of suspending the desired mass of water is via high expansion-ratio aqueous foams. Because, in practice, the foam would be generated using the combustible gaseous contents of the containment vessel, combustion occurs inside the foam cells. Although foams generated with inert gas have been well studied for use in fire fighting, little is known about combustion in foams generated with flammable mixtures. To help assess the usefulness of aqueous foams in a mitigation plan, several open-tube tests and more than 100 closed-vessel tests of hydrogen/air combustion, with and without foam were conducted. At low and intermediate hydrogen concentrations, the foam has little effect on the ultimate isochoric pressure rise. Above 15% hydrogen concentration, the foam causes a significant reduction in the pressure rise. The maximum effect occurs at about 28% hydrogen (the stoichiometric limit is 29.6% hydrogen) where the peak overpressure is reduced by 2 1/2. Despite this overall pressure reduction, the flame speed is increased by up to an order of magnitude for combustion in the foam, and strong pressure fluctuations are observed near a hydrogen concentration of 23%

  16. Hydrogen combustion in aqueous foams

    International Nuclear Information System (INIS)

    Baer, M.; Griffiths, S.; Shepherd, J.

    1983-01-01

    Water fogs are recognized as an effective means to mitigate the effects of large-scale hydrogen combustion that might accompany some loss-of-coolant nuclear reactor accidents. Fogs of sufficiently high density to produce large beneficial effects may, however, be difficult to generate and maintain. An alternate method of suspending the desired mass of water is via high expansion-ratio aqueous foams. Because, in practice, the foam would be generated using the combustible gaseous contents of the containment vessel, combustion occurs inside the foam cells. Although foams generated with inert gas have been well studied for use in fire fighting, little is known about combustion in foams generated with flammable mixtures. To help assess the usefulness of aqueous foams in a mitigation plan, we have conducted several open tube tests and over one hundred closed vessel tests of hydrogen/air combustion with and without foam. At low and intermediate hydrogen concentrations, the foam has little effect on the ultimate isochoric pressure rise. Above 15% hydrogen concentration, the foam causes a significant reduction in the pressure rise. The maximum effect occurs at about 28% hydrogen (the stoichiometric limit is 29.6% hydrogen) where the peak overpressure is reduced by a factor of two and one-half. Despite this overall pressure reduction, the flame speed is increase by up to an order of magnitude for combustion in the foam and strong pressure fluctuations are observed near a hydrogen concentration of 23%

  17. Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

    Science.gov (United States)

    Guerrero-Barajas, Claudia; Ordaz, Alberto; García-Solares, Selene Montserrat; Garibay-Orijel, Claudio; Bastida-González, Fernando; Zárate-Segura, Paola Berenice

    2015-01-01

    The importance of microbial sulfate reduction relies on the various applications that it offers in environmental biotechnology. Engineered sulfate reduction is used in industrial wastewater treatment to remove large concentrations of sulfate along with the chemical oxygen demand (COD) and heavy metals. The most common approach to the process is with anaerobic bioreactors in which sulfidogenic sludge is obtained through adaptation of predominantly methanogenic granular sludge to sulfidogenesis. This process may take a long time and does not always eliminate the competition for substrate due to the presence of methanogens in the sludge. In this work, we propose a novel approach to obtain sulfidogenic sludge in which hydrothermal vents sediments are the original source of microorganisms. The microbial community developed in the presence of sulfate and volatile fatty acids is wide enough to sustain sulfate reduction over a long period of time without exhibiting inhibition due to sulfide. This protocol describes the procedure to generate the sludge from the sediments in an upflow anaerobic sludge blanket (UASB) type of reactor. Furthermore, the protocol presents the procedure to demonstrate the capability of the sludge to remove by reductive dechlorination a model of a highly toxic organic pollutant such as trichloroethylene (TCE). The protocol is divided in three stages: (1) the formation of the sludge and the determination of its sulfate reducing activity in the UASB, (2) the experiment to remove the TCE by the sludge, and (3) the identification of microorganisms in the sludge after the TCE reduction. Although in this case the sediments were taken from a site located in Mexico, the generation of a sulfidogenic sludge by using this procedure may work if a different source of sediments is taken since marine sediments are a natural pool of microorganisms that may be enriched in sulfate reducing bacteria. PMID:26555802

  18. Enhancing faecal sludge management in peri-urban areas of Lusaka through faecal sludge valorisation: challenges and opportunities

    Science.gov (United States)

    Tembo, J. M.; Nyirenda, E.; Nyambe, I.

    2017-03-01

    Lusaka, the capital city of Zambia, has two million inhabitants with 70% residing in peri-urban areas. Ninety (90) % of this population employ pit latrines for excretion generating approximately 22,680 tons of faecal sludge per annum. This sludge is inadequately managed hence of the generated amount, over 60% remains within the residential environment thereby compromising both the environment and public health. To foster a solution to this problem, a study was commissioned to assess faecal sludge valorisation potential and how it would impact on Faecal Sludge Management. The study evaluated policy, institutional and regulatory frameworks, sanitation practices including latrine construction and usage aspects and also characterised the faecal sludge for selected parameters relevant to valorisation. Four peri-urban areas were adopted as study sites. Policy issues together with existing institutional and regulatory frameworks were assessed through literature review. Sanitation practices were evaluated through physical observations, focus group discussions, interviews and questionnaire administration. Faecal sludge characterisation was through sampling and analysis. It was observed that there are policy gaps in fostering faecal sludge valorisation. Sanitation practices and latrines construction also do not favour valorisation. The quality of the raw sludge has potential for valorisation though again, some parameters like solid waste content require drastic changes in sanitation practices in order not to compromise the reuse potential of the sludge. It was concluded that if faecal sludge management is to be enhanced through valorisation, there is need to have policies promoting pit latrine faecal sludge reuse and strengthened regulatory and institutional frameworks in this respect.

  19. Modeling of the reburning process using sewage sludge-derived syngas.

    Science.gov (United States)

    Werle, Sebastian

    2012-04-01

    Gasification of sewage sludge can provide clean and effective reburning fuel for combustion applications. The motivation of this work was to define the reburning potential of the sewage sludge gasification gas (syngas). A numerical simulation of the co-combustion process of syngas in a hard coal-fired boiler was done. All calculations were performed using the Chemkin programme and a plug-flow reactor model was used. The calculations were modelled using the GRI-Mech 2.11 mechanism. The highest conversions for nitric oxide (NO) were obtained at temperatures of approximately 1000-1200K. The combustion of hard coal with sewage sludge-derived syngas reduces NO emissions. The highest reduction efficiency (>90%) was achieved when the molar flow ratio of the syngas was 15%. Calculations show that the analysed syngas can provide better results than advanced reburning (connected with ammonia injection), which is more complicated process. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Have combustible cigarettes met their match? The nicotine delivery profiles and harmful constituent exposures of second-generation and third-generation electronic cigarette users

    Science.gov (United States)

    Wagener, Theodore L; Floyd, Evan L; Stepanov, Irina; Driskill, Leslie M; Frank, Summer G; Meier, Ellen; Leavens, Eleanor L; Tackett, Alayna P; Molina, Neil; Queimado, Lurdes

    2017-01-01

    Introduction Electronic cigarettes’ (e-cigarettes) viability as a public health strategy to end smoking will likely be determined by their ability to mimic the pharmacokinetic profile of a cigarette while also exposing users to significantly lower levels of harmful/potentially harmful constituents (HPHCs). The present study examined the nicotine delivery profile of third- (G3) versus second-generation (G2) e-cigarette devices and their users’ exposure to nicotine and select HPHCs compared with cigarette smokers. Methods 30 participants (10 smokers, 9 G2 and 11 G3 users) completed baseline questionnaires and provided exhaled carbon monoxide (eCO), saliva and urine samples. Following a 12-hour nicotine abstinence, G2 and G3 users completed a 2-hour vaping session (ie, 5 min, 10-puff bout followed by ad libitum puffing for 115 min). Blood samples, subjective effects, device characteristics and e-liquid consumption were assessed. Results Smokers, G2 and G3 users had similar baseline levels of cotinine, but smokers had 4 and 7 times higher levels of eCO (pvaped e-cigarette liquids with significantly lower nicotine concentrations. During the vaping session, G3 users achieved significantly higher plasma nicotine concentrations than G2 users following the first 10 puffs (17.5 vs 7.3 ng/mL, respectively) and at 25 and 40 min of ad libitum use. G3 users consumed significantly more e-liquid than G2 users. Vaping urges/withdrawal were reduced following 10 puffs, with no significant differences between device groups. Discussion Under normal use conditions, both G2 and G3 devices deliver cigarette-like amounts of nicotine, but G3 devices matched the amount and speed of nicotine delivery of a conventional cigarette. Compared with cigarettes, G2 and G3 e-cigarettes resulted in significantly lower levels of exposure to a potent lung carcinogen and cardiovascular toxicant. These findings have significant implications for understanding the addiction potential of these devices and

  1. Verification of vermural stabilization of ash from biomass and sewage sludge

    Science.gov (United States)

    Adamkova, L.; Kucerova, D.; Lyckova, B.; Kucerova, R.; Takac, D.

    2017-10-01

    The aim of this study was to find dependence on biofuels and sludge from sewage treatment plants in the vermicomposting process. In the framework of the research carried out at our workplace, a project aimed at finding an appropriate method for the reprocessing of problematic biodegradable waste and asphalt from combustion biomass was used as a raw material for the production of rectification substrate and sludge from sewage treatment plants that could be used as Secondary raw material.

  2. Combustion Stratification for Naphtha from CI Combustion to PPC

    KAUST Repository

    Vallinayagam, R.

    2017-03-28

    This study demonstrates the combustion stratification from conventional compression ignition (CI) combustion to partially premixed combustion (PPC). Experiments are performed in an optical CI engine at a speed of 1200 rpm for diesel and naphtha (RON = 46). The motored pressure at TDC is maintained at 35 bar and fuelMEP is kept constant at 5.1 bar to account for the difference in fuel properties between naphtha and diesel. Single injection strategy is employed and the fuel is injected at a pressure of 800 bar. Photron FASTCAM SA4 that captures in-cylinder combustion at the rate of 10000 frames per second is employed. The captured high speed video is processed to study the combustion homogeneity based on an algorithm reported in previous studies. Starting from late fuel injection timings, combustion stratification is investigated by advancing the fuel injection timings. For late start of injection (SOI), a direct link between SOI and combustion phasing is noticed. At early SOI, combustion phasing depends on both intake air temperature and SOI. In order to match the combustion phasing (CA50) of diesel, the intake air temperature is increased to 90°C for naphtha. The combustion stratification from CI to PPC is also investigated for various level of dilution by displacing oxygen with nitrogen in the intake. The start of combustion (SOC) was delayed with the increase in dilution and to compensate for this, the intake air temperature is increased. The mixture homogeneity is enhanced for higher dilution due to longer ignition delay. The results show that high speed image is initially blue and then turned yellow, indicating soot formation and oxidation. The luminosity of combustion images decreases with early SOI and increased dilution. The images are processed to generate the level of stratification based on the image intensity. The level of stratification is same for diesel and naphtha at various SOI. When O concentration in the intake is decreased to 17.7% and 14

  3. Alcohol combustion chemistry

    KAUST Repository

    Sarathy, Mani

    2014-10-01

    Alternative transportation fuels, preferably from renewable sources, include alcohols with up to five or even more carbon atoms. They are considered promising because they can be derived from biological matter via established and new processes. In addition, many of their physical-chemical properties are compatible with the requirements of modern engines, which make them attractive either as replacements for fossil fuels or as fuel additives. Indeed, alcohol fuels have been used since the early years of automobile production, particularly in Brazil, where ethanol has a long history of use as an automobile fuel. Recently, increasing attention has been paid to the use of non-petroleum-based fuels made from biological sources, including alcohols (predominantly ethanol), as important liquid biofuels. Today, the ethanol fuel that is offered in the market is mainly made from sugar cane or corn. Its production as a first-generation biofuel, especially in North America, has been associated with publicly discussed drawbacks, such as reduction in the food supply, need for fertilization, extensive water usage, and other ecological concerns. More environmentally friendly processes are being considered to produce alcohols from inedible plants or plant parts on wasteland. While biofuel production and its use (especially ethanol and biodiesel) in internal combustion engines have been the focus of several recent reviews, a dedicated overview and summary of research on alcohol combustion chemistry is still lacking. Besides ethanol, many linear and branched members of the alcohol family, from methanol to hexanols, have been studied, with a particular emphasis on butanols. These fuels and their combustion properties, including their ignition, flame propagation, and extinction characteristics, their pyrolysis and oxidation reactions, and their potential to produce pollutant emissions have been intensively investigated in dedicated experiments on the laboratory and the engine scale

  4. Analysis of the internal temperature of the combustion chamber of a compact system of co-generation; Analise das temperaturas internas da camara de combustao de um sistema compacto de co-geracao

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Joao B.F. [Universidade de Fortaleza (UNIFOR), CE (Brazil)], email: furlan@unifor.br; Couto, Heraldo S. [Instituto Nacional de Pesquisas Espaciais (INPE), Cachoeira Paulista, SP (Brazil)], email: heraldo@lcp.inpe.br; Holanda, Carlos A.M. de [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Metalurgica e de Materiais], email: almir@metalmat.ufc.br

    2008-07-01

    Nowadays, the energy deficit represents one of the biggest governmental challenges, since there is still a great number of communities living in areas without electricity energy; and thus without access to electro-electronic equipment such as television, refrigerators, computers. The main focus of this work is to present the possibility of electricity energy generation in conjunction with the frozen or hot water production in for places without electricity transmission nets or even any type of alternative power plants. The system is based on the standard air cycle called Brayton cycle composed of a turbo-compressor model 4LGZ from BorgWarner, a combustion chamber, a power turbine, a heat exchanger, a water-ammonia chiller, a 5.0 kV A generator, and a command panel for automation and distribution of energy. This system that uses natural gas or LPG, will supply electric energy from the generator, hot water from the heat exchange with the gases of combustion, and water frozen from chiller using as the hot source the gases proceeding from the power system. The prototype is already being tested and the first results obtained are excellent. In this paper, we analyze the internal combustion chamber temperatures. (author)

  5. Co-treatment of fruit and vegetable waste in sludge digesters. An analysis of the relationship among bio-methane generation, process stability and digestate phytotoxicity.

    Science.gov (United States)

    Di Maria, Francesco; Sordi, Alessio; Cirulli, Giuseppe; Gigliotti, Giovanni; Massaccesi, Luisa; Cucina, Mirko

    2014-09-01

    The co-digestion of a variable amount of fruit and vegetable waste in a waste mixed sludge digester was investigated using a pilot scale apparatus. The organic loading rate (OLR) was increased from 1.46 kg VS/m(3) day to 2.8 kg VS/m(3) day. The hydraulic retention time was reduced from 14 days to about 10 days. Specific bio-methane production increased from about 90 NL/kg VS to the maximum value of about 430 NL/kg VS when OLR was increased from 1.46 kg VS/m(3) day to 2.1 kg VS/m(3) day. A higher OLR caused an excessive reduction in the hydraulic retention time, enhancing microorganism wash out. Process stability evaluated by the total volatile fatty acids concentration (mg/l) to the alkalinity buffer capacity (eq. mg/l CaCO3) ratio (i.e. FOS/TAC) criterion was stability for OLR 2.46 kg VS/m(3) day, GI decreased rapidly. This corresponding trend between FOS/TAC and GI was further investigated by the definition of the GI ratio (GIR) parameter. Comparison between GIR and FOS/TAC suggests that GI could be a suitable criterion for evaluating process stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Tubular combustion

    CERN Document Server

    Ishizuka, Satoru

    2014-01-01

    Tubular combustors are cylindrical tubes where flame ignition and propagation occur in a spatially confined, highly controlled environment, in a nearly flat, elongated geometry. This allows for some unique advantages where extremely even heat dispersion is required over a large surface while still maintaining fuel efficiency. Tubular combustors also allow for easy flexibility in type of fuel source, allowing for quick changeover to meet various needs and changing fuel pricing. This new addition to the MP sustainable energy series will provide the most up-to-date research on tubular combustion--some of it only now coming out of private proprietary protection. Plentiful examples of current applications along with a good explanation of background theory will offer readers an invaluable guide on this promising energy technology. Highlights include: * An introduction to the theory of tubular flames * The "how to" of maintaining stability of tubular flames through continuous combustion * Examples of both small-scal...

  7. High Level Waste System Impacts from Acid Dissolution of Sludge

    Energy Technology Data Exchange (ETDEWEB)

    KETUSKY, EDWARD

    2006-04-20

    This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

  8. Costs and economic efficiency of the drying of sewage sludges; Kosten und Wirtschaftlichkeit der Klaerschlammtrocknung

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Ulrich [Haarslev Industries A/S, Herlev (Denmark). Marketing and Business Development

    2013-03-01

    New methods of the thermal utilization have to be created due to the fact that agricultural utilisation of sewage sludge and the use in the reclamation due to stringent limit values and enhanced quality criteria are available restricted in future. The incineration of mechanically dewatered and dried sewage sludge is performed in mono-combustion plants as well as in coal-fired power plants. The author of the contribution under consideration reports on the costs and economic efficiency of the drying of sewage sludge. The drying of sewage sludge may perform an important and reasonable contribution to the utilization of municipal sewage sludge. The selection of a suitable drying process should ever depend on the local realities. Proved and suitable technologies are available for every application. Before the decision for a certain provider, one should examine reference plants and consider specific experiences of the operator among the decision-making.

  9. Thermal treatment of sewage sludge from waste water. Tratamiento termico de lodos procedentes de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Andreottola, G. (Universidad de Trento (Italy)); Canziani, R.; Ragazzi, M. (Politicnico de Milan (Italy))

    1994-01-01

    Thermal Treatment of sewage sludge can be beneficial as a pre-treatment step of many treatment/disposal options, but above all, it allows the recovery of the energetic content sludge. Energy recovery from sewage sludge can be performed in many ways; direct incineration thermal drying followed by incineration and co-combustion with municipal solid wastes or other non conventional fuels. Another option is the recovery of waste energy (e.g. from an endo thermal engine using biogas as fuel) to dry sludge wich, in turn can be used as a fuel. The paper will evaluate several options of thermal treatment of sewage sludge, with particular emphasis on the energetic yield from different processes. (Author)

  10. Advanced Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, Gordon R. [NETL

    2013-03-11

    The activity reported in this presentation is to provide the mechanical and physical property information needed to allow rational design, development and/or choice of alloys, manufacturing approaches, and environmental exposure and component life models to enable oxy-fuel combustion boilers to operate at Ultra-Supercritical (up to 650{degrees}C & between 22-30 MPa) and/or Advanced Ultra-Supercritical conditions (760{degrees}C & 35 MPa).

  11. Combustion instability control in the model of combustion chamber

    International Nuclear Information System (INIS)

    Akhmadullin, A N; Ahmethanov, E N; Iovleva, O V; Mitrofanov, G A

    2013-01-01

    An experimental study of the influence of external periodic perturbations on the instability of the combustion chamber in a pulsating combustion. As an external periodic disturbances were used sound waves emitted by the electrodynamics. The purpose of the study was to determine the possibility of using the method of external periodic perturbation to control the combustion instability. The study was conducted on a specially created model of the combustion chamber with a swirl burner in the frequency range from 100 to 1400 Hz. The study found that the method of external periodic perturbations may be used to control combustion instability. Depending on the frequency of the external periodic perturbation is observed as an increase and decrease in the amplitude of the oscillations in the combustion chamber. These effects are due to the mechanisms of synchronous and asynchronous action. External periodic disturbance generated in the path feeding the gaseous fuel, showing the high efficiency of the method of management in terms of energy costs. Power required to initiate periodic disturbances (50 W) is significantly smaller than the thermal capacity of the combustion chamber (100 kW)

  12. Determining organic pollutants in automotive industry sludge.

    Science.gov (United States)

    Munaretto, Juliana S; Wonghon, Audrey L; von Mühlen, Carin

    2012-12-01

    In Brazil, the policy for disposing industrial sludge is changing from an emphasis on using controlled landfills to other treatment or co-processing methods; however, the monitoring of organic pollutants is not mandatory. The present study evaluated two general screening methods for organic pollutants in sludge generated in an automotive industrial complex in southern Brazil. The screening was performed using Soxhlet and sonication extractions and Gas Chromatograph coupled with Quadrupole Mass Spectrometry (GC/qMS). It was concluded that both techniques were effective and that most of the compounds identified were alkanes, phenols and esters. Important pollutants were detected in the sludge, which confirms the necessity of monitoring this type of residue.

  13. 76 FR 12923 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2011-03-09

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... pollutants for existing stationary spark ignition reciprocating internal combustion engines. The final rule... reciprocating internal combustion generation, engine. transmission, or distribution. 622110 Medical and surgical...

  14. 75 FR 75937 - National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion...

    Science.gov (United States)

    2010-12-07

    ... National Emission Standards for Hazardous Air Pollutants for Reciprocating Internal Combustion Engines... internal combustion engines. Subsequently, the Administrator received two petitions for reconsideration... Any industry using a stationary 2211 Electric power reciprocating internal generation, combustion...

  15. Changes on sewage sludge stability after greenhouse drying

    Science.gov (United States)

    Soriano-Disla, J. M.; Houot, S.; Imhoff, M.; Valentin, N.; Gómez, I.; Navarro-Pedreño, J.

    2009-04-01

    The progressive implementation of the Urban Waste Water Treatment Directive 91/271/EEC in all the European member states is increasing the quantities of sewage sludge requiring disposal. Sludge application onto cultivated soils as organic fertilizers allows the recycling of nutrients. The application of only dehydrated sludges has generated many problems including unpleasant odours and difficult management (regarding transport and application) related to their high water content. One way to overcome these problems, in a cheap and clean way, is the drying of sludges using the energy of the sun under greenhouse conditions. This drying may affect sludge chemical characteristics including organic matter stability and nitrogen availability, parameters which have to be controlled for the proper management of dry sludge application onto soils. For this reason, the main aim of this work was to study the impact of greenhouse drying of different sewage sludges on their organic matter stability and nitrogen availability, assessed by biochemical fractionation and mineralization assays. Three sewage sludges were sampled before (dehydrated sludges) and after greenhouse drying (dried sludges). The analyses consisted of: humidity, organic matter, mineral and organic N contents, N and C mineralization during 91-day laboratory incubations in controlled conditions, and biochemical fractionation using the Van Soest procedure. Greenhouse drying decreased the water content from 70-80% to 10% and also the odours, both of which will improve the management of the final product from the perspective of application and transport. We also found that drying reduced the organic matter content of the sludges but not the biodegradability of the remaining carbon. Organic N mineralization occurred during greenhouse drying, explaining why mineral N content tended to increase and the potential mineralization of organic nitrogen decreased after greenhouse drying. The biochemical stability did not

  16. Decomposition of water into highly combustible hydroxyl gas used in ...

    African Journals Online (AJOL)

    The method proposed involves the decomposition of water into highly combustible hydroxyl gas via electrolysis, which is used in internal combustion engines of electrical generators for electricity generation. The by-product obtained from combustion of this gas is water vapour and oxygen to replenish the atmosphere.

  17. Analysis of petroleum oily sludge producing in petroleum field of Rio Grande do Norte, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Cicero de Souza; Lima, Regineide Oliveira; Silva, Edjane Fabiula Buriti da; Castro, Kesia Kelly Vieira de; Chiavone Filho, Osvaldo; Araujo, Antonio Souza de [Universidade Federal do Rio Grande do Norte (UFRN), RN (Brazil)

    2012-07-01

    In exploration and production of petroleum is generated solid waste different and components other. The petroleum oily sludge is a complex mix of components different (water, oil and solid). The petroleum oily sludge generally has other residues and is formed during production and operations, transport, storage and petroleum refining (atmospheric residue, vacuum residue and catalytic cracking residue). However, according to its origin, the compositions can be found quite varied for sludge. Observing the process steps production and refining is possible to locate its main sources and percentage contributions in terms of waste generation. The elemental analysis was performed with oily sludge from region and it showed different composition. For carbon element and hydrogen, small differences was observed, but for was observed greater differences for Oxygen element. The sludge has different inorganic and organic composition. The sludge from oil water separator (OWS) 2 showed a greater amount of oil (94.88%), this may indicate a residue of aggregate high for petroleum industry. In analysis of Saturates, Aromatics, Resins and Asphaltenes (SARA), the sludge from unloading showed amount high of saturates. The inorganic material separated from sludge was characterized and sludge from OWS 2 had high amount sulfur (41.57%). The sludge analyzed showed organic components high values, so it can be treated and reprocessed in process units petroleum industry. The analysis thermal degradation had a better setting for treated oily sludge. (author)

  18. Chemical characterization of bottom ashes generated during combustion of a Colombian mineral coal in a thermal power plant; Caracterizacao quimica das cinzas de fundo originadas pela combustao, em usina termoeletrica, de um carvao mineral do nordeste da Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, H.S.; Nogueira, R.E.F.Q.; Lobo, C.J.S.; Nobre, A.I.S.; Sales, J.C.; Silva, C.J.M., E-mail: hspfisica@hotmail.com [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Centro de Tecnologia. Dept. de Engenharia Metalurgica e de Materiais

    2012-07-01

    Bottom ashes generated during combustion of a mineral coal from Colombia were characterized by X-ray fluorescence spectrometry and X-ray diffraction. The interest in this particular coal is due to the fact that it will be used by a thermal power plant in Ceara, Northeastern Brazil, where it could produce over 900 tons of different residues/combustion products every day. Results from Xray fluorescence allowed identification and quantification of elements present in the sample: silicon (59,17%), aluminum (13,17%), iron (10,74%), potassium (6,11%), titanium (2,91%), calcium (4,97%), sulphur (0,84%) and others (2,09%). The X-ray diffraction revealed patterns from silica, mullite, calcium sulphate and hydrated sodium. Results obtained so far indicate that the material is a potential raw-material for use in the formulation of ceramic components (author)

  19. Processing of converter sludges on the basis of thermal-oxidative coking with coals

    Science.gov (United States)

    Kuznetsov, S. N.; Shkoller, M. B.; Protopopov, E. V.; Kazimirov, S. A.; Temlyantsev, M. V.

    2017-09-01

    The paper deals with the solution of an important problem related to the recycling of converter sludge. High moisture and fine fractional composition of waste causes the application of their deep dehydration and lumping. To reduce environmental emissions the non-thermal method of dehydration is considered - adsorption-contact drying. As a sorbent, the pyrolysis product of coals from the Kansko-Achinsky basin - brown coal semi-coke (BSC) obtained by the technology “Thermokoks”. Experimental data on the dehydration of high-moisture wastes with the help of BSC showed high efficiency of the selected material. The lumping of the dried converter dust was carried out by thermo-chemical coking with coals of grades GZh (gas fat coal) and Zh (fat coal). As a result, an iron-containing product was obtained - ferrocoke, which is characterized by almost complete reduction of iron oxides, as well as zinc transition into a vapor state, and is removed with gaseous process products. Based on the results of the experimental data a process basic diagram of the utilization of converter sludge to produce ferrocoke was, which can be effectively used in various metallurgical aggregates, for example, blast furnaces, converters and electric arc furnaces. In the basic technological scheme heat generated by ferrocoke cooling and the energy of the combustion products after the separation of zinc in the gas turbine plant will be used.

  20. Electroosmotic dewatering of chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge

    DEFF Research Database (Denmark)

    Hansen, H.K.; Christensen, Iben Vernegren; Ottosen, Lisbeth M.

    2003-01-01

    Electroosmotic dewatering has been tested in laboratory cells on four different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material. Casagra......Electroosmotic dewatering has been tested in laboratory cells on four different porous materials: chalk sludge, iron hydroxide sludge, wet fly ash and biomass sludge from enzyme production. In all cases it was possible to remove water when passing electric DC current through the material...

  1. Extending the use of dewatered alum sludge as a P-trapping material in effluent purification : study on two separate water treatment sludges

    OpenAIRE

    Zhao, Y.Q.; Yang, Y.

    2010-01-01

    The generation of alum sludge from drinking water purification process remains inevitable when aluminium sulphate is used as primary coagulant for raw water coagulation. Sustainable managing such the sludge becomes an increasing concern in water industry. Its beneficial reuse is therefore highly desirable and has attracted considerable research efforts. In view of the novel development of alum sludge as a value-added raw material for beneficial reuse for wastewater treatment, this study exami...

  2. Review on innovative techniques in oil sludge bioremediation

    Science.gov (United States)

    Mahdi, Abdullah M. El; Aziz, Hamidi Abdul; Eqab, Eqab Sanoosi

    2017-10-01

    Petroleum hydrocarbon waste is produced in worldwide refineries in significant amount. In Libya, approximately 10,000 tons of oil sludge is generated in oil refineries (hydrocarbon waste mixtures) annually. Insufficient treatment of those wastes can threaten the human health and safety as well as our environment. One of the major challenges faced by petroleum refineries is the safe disposal of oil sludge generated during the cleaning and refining process stages of crude storage facilities. This paper reviews the hydrocarbon sludge characteristics and conventional methods for remediation of oil hydrocarbon from sludge. This study intensively focuses on earlier literature to describe the recently selected innovation technology in oily hydrocarbon sludge bioremediation process. Conventional characterization parameters or measurable factors can be gathered in chemical, physical, and biological parameters: (1) Chemical parameters are consequently necessary in the case of utilization of topsoil environment when they become relevant to the presence of nutrients and toxic compounds; (2) Physical parameters provide general data on sludge process and hand ability; (3) Biological parameters provide data on microbial activity and organic matter presence, which will be used to evaluate the safety of the facilities. The objective of this research is to promote the bioremediating oil sludge feasibility from Marsa El Hariga Terminal and Refinery (Tobruk).

  3. Efficient catalysis by MgCl2 in hydrogen generation via hydrolysis of Mg-based hydride prepared by hydriding combustion synthesis.

    Science.gov (United States)

    Zhao, Zelun; Zhu, Yunfeng; Li, Liquan

    2012-06-04

    Magnesium chloride efficiently catalyzed the hydrolysis of Mg-based hydride prepared by hydriding combustion synthesis. Hydrogen yield of 1635 mL g(-1) was obtained (MgH(2)), i.e. with 96% conversion in 30 min at 303 K.

  4. Leaching of Heavy Metals Using SPLP Method from Fired Clay Brick Incorporating with Sewage Sludge

    Science.gov (United States)

    Kadir, Aeslina Abdul; Salim, Nurul Salhana Abdul; Amira Sarani, Noor; Aqma Izurin Rahmat, Nur

    2017-05-01

    Sewage sludge is a by-product generate from wastewater treatment process. The sewage sludge contains significant trace metal such as Cr, Mn, Ni, Cu, Zn, As, Cd and Pb which are toxic to the environment. Sewage sludge is disposed of by landfilling method. However, this option not suitable because of land restriction and environmental control regulations imposed. Therefore, sewage sludge from wastewater treatment plant was incorporated into fired clay brick to produce good quality of brick as well as reducing heavy metals from sludge itself. Sewage sludge with 0%, 1%, 5%, 10% and 20% of were incorporated into fired clay bricks and fired at 1050°C temperature with heating rates of 1°C/min. The brick sample then crushed and sieved through 9.5 mm sieve for Synthetic Precipitation Leaching Procedure (SPLP). From the results, incorporation up to 20% of sewage sludge has leached less heavy metals and compliance with USEPA standard.

  5. Effect of gamma-ray irradiation on the dewaterability of waste activated sludge

    Science.gov (United States)

    Wu, Yuqi; Jiang, Yinghe; Ke, Guojun; Liu, Yingjiu

    2017-01-01

    The effect of gamma-ray irradiation on waste activated sludge (WAS) dewaterability was investigated with irradiation doses of 0-15 kGy. Time to filter (TTF50), specific resistance of filtration (SRF) and water content of sludge cake were measured to evaluate sludge dewaterability. Soluble chemical oxygen demand (SCOD), soluble extracellular polymeric substances (EPS) concentration and sludge particle size were determined to explain changes in sludge dewaterability. The optimal irradiation dose to obtain the maximum dewaterability characteristics was 1-4 kGy, which generated sludge with optimal disintegration (1.5-4.0%), soluble EPS concentration (590-750 mg/L) and particle size distribution (100-115 μm diameter). The combination of irradiation and cationic polyacrylamide (CPAM) addition exhibited minimal synergistic effect on increasing sludge dewatering rate compared with CPAM conditioning alone.

  6. Jet plume injection and combustion system for internal combustion engines

    Science.gov (United States)

    Oppenheim, Antoni K.; Maxson, James A.; Hensinger, David M.

    1993-01-01

    An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.

  7. Economics of the hydrolysis of cellulosic sludge to glucose.

    Science.gov (United States)

    Mora, Sandeep; Banerjee, Sujit

    2013-08-01

    Cellulosic sludge from paper mills making bleached products can be enzymatically converted to glucose. A kinetic model that accounts for product inhibition was used to estimate the cost:benefits of the process. In the proposed scheme, the sludge is enzymatically hydrolyzed in a sequence of CSTRs, the ash separated, and the product glucose concentrated through reverse osmosis. The water recovered is mostly recycled. By far, the most important economic variable is the value of the glucose. However, even if the glucose is assumed to be of no value the avoided cost of sludge disposal approximately offsets the process costs. The approach should generate significant revenue if the glucose is valued at market.

  8. Vitrification as an alternative to landfilling of tannery sewage sludge.

    Science.gov (United States)

    Celary, Piotr; Sobik-Szołtysek, Jolanta

    2014-12-01

    Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with flotation sewage sludge, and 45% v/v and 5% v/v, respectively, for precipitation sewage sludge. These combinations allowed for obtaining products with negligible heavy metal leaching levels and hardness similar to commercial glass, which suggests they could be potentially used as construction aggregate substitutes. Incineration of sewage sludge before the vitrification process lead to

  9. Sludge pumping in water treatment

    International Nuclear Information System (INIS)

    Solar Manuel, M. A.

    2010-01-01

    In water treatment processes is frequent to separate residual solids, with sludge shape, and minimize its volume in a later management. the technologies to applicate include pumping across pipelines, even to long distance. In wastewater treatment plants (WWTP), the management of these sludges is very important because their characteristics affect load losses calculation. Pumping sludge can modify its behavior and pumping frequency can concern treatment process. This paper explains advantages and disadvantages of different pumps to realize transportation sludge operations. (Author) 11 refs.

  10. Characterisation of ashes produced by co-combustion of recovered fuels and peat

    Energy Technology Data Exchange (ETDEWEB)

    Frankenhaeuser, M. [Borealis Polymers Oy, Porvoo (Finland)

    1997-10-01

    The current project focuses on eventual changes in ash characteristics during co-combustion of refuse derived fuel with coal, peat, wood or bark, which could lead to slagging, fouling and corrosion in the boiler. Ashes were produced at fluidised bed (FB) combustion conditions in the 15 kW reactor at VTT Energy, Jyvaeskylae, the fly ash captured by the cyclone was further analysed by XRF at Outokumpu Geotechnical Laboratory, Outokumpu. The sintering behaviour of these ashes was investigated using a test procedure developed at the Combustion Chemistry Research Group at Aabo Akademi University. The current extended programme includes a Danish refuse-derived fuel (RDF), co-combusted with bark/coal (5 tests) and wood/coal (2 tests), a RF from Jyvaskyla (2 tests with peat/coal) and de-inking sludges co- combusted at full-scale with wood waste or paper mill sludge (4 ashes provided by IVO Power). Ash pellets were thermally treated in nitrogen in order to avoid residual carbon combustion. The results obtained show no sintering tendencies below 600 deg C, significant changes in sintering are seen with pellets treated at 1000 deg C. Ash from 100 % RDF combustion does not sinter, 25 % RDF co-combustion with wood and peat, respectively, gives an insignificant effect. The most severe sintering occurs during co-combustion of RDF with bark. Contrary to the earlier hypothesis a 25 % coal addition seems to have a negative effect on all fuel blends. Analysis of the sintering results versus ash chemical composition shows, that (again), in general, an increased level of alkali chlorides and sulphates gives increased sintering. Finally, some results on sintering tendency measurements on ashes from full-scale CFB co-combustion of deinking sludge with wood waste and paper mill sludge are given. This shows that these ashes show very little, if any, sintering tendency, which can be explained from ash chemistry

  11. RELATIONSHIP BETWEEN SLUDGE DEWATERABILITY NUMBER ...

    African Journals Online (AJOL)

    A representative of a sludge sample collected from the same source was filtered under the same environmental condition and the result analysed with two different concepts. One method of analysis uses Sludge Dewaterability Number, while the second employed the Carman's Specific resistance concept in sludge ...

  12. High Combustion Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL's High-Pressure Combustion Research Facility in Morgantown, WV, researchers can investigate new high-pressure, high-temperature hydrogen turbine combustion...

  13. Combustion Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Combustion Research Laboratory facilitates the development of new combustion systems or improves the operation of existing systems to meet the Army's mission for...

  14. Impact of aerobic stabilization on the characteristics of treatment sludge in the leather tanning industry.

    Science.gov (United States)

    Cokgor, Emine Ubay; Aydinli, Ebru; Tas, Didem Okutman; Zengin, Gulsum Emel; Orhon, Derin

    2014-01-01

    The efficiency of aerobic stabilization on the treatment sludge generated from the leather industry was investigated to meet the expected characteristics and conditions of sludge prior to landfill. The sludge types subjected to aerobic stabilization were chemical treatment sludge, biological excess sludge, and the mixture of both chemical and biological sludges. At the end of 23 days of stabilization, suspended solids, volatile suspended solids and total organic carbon removal efficiencies were determined as 17%, 19% and 23% for biological sludge 31%, 35% and 54% for chemical sludge, and 32%, 34% and 63% for the mixture of both chemical and biological sludges, respectively. Model simulations of the respirometric oxygen uptake rate measurements showed that the ratio of active biomass remained the same at the end of the stabilization for all the sludge samples. Although mixing the chemical and biological sludges resulted in a relatively effective organic carbon and solids removal, the level of stabilization achieved remained clearly below the required level of organic carbon content for landfill. These findings indicate the potential risk of setting numerical restrictions without referring to proper scientific support.

  15. Mineralization of nitrogen from pelletized sewage sludge - a laboratory incubation study

    Energy Technology Data Exchange (ETDEWEB)

    Wattiez, Anne-Laure

    2000-07-01

    Nitrogen limits the productivity of most ecosystems, but can also cause environmental problems. With the increasing amount of sludge generated by better wastewater treatment, land application of pelletized sludge appears as a combined solution to waste disposal and plant nitrogen nutrition issues. Six types of sludge pellets/granules, containing different mixtures of sludge, ash and/or lime have been inoculated and incubated for 8 weeks at 20 deg C in the dark, to study N net mineralisation rates. Laboratory results showed no indication of general differences between sludge/ash and sludge/lime mixtures, with respect to N mineralisation and nitrification, but some differences between Umeaa pellets and GaevIe granules were discernible. The higher net N mineralisation rates in pellets appeared to be related to sludge properties. On the contrary pellets had a low level of nitrification, which might be explained by preliminary heat treatment of the sludge and the seemingly slow recolonization of nitrifiers. It is also believed that considerable amounts of N were lost, and that the major route for these losses was ammonia volatilisation. From an economical point of view, sludge pelletisation appears to be the most cost-effective means of disposal. It transforms sludge into a valuable, odourless and storable fertiliser or heat source. Some income could even be expected. The benefits obtained from an increased tree growth could justify forest fertilisation with pelletized sludge, but further research is needed to determine more precisely the possible growth increment and the consequences on the environment.

  16. Mineralization of nitrogen from pelletized sewage sludge - a laboratory incubation study

    International Nuclear Information System (INIS)

    Wattiez, Anne-Laure

    2000-01-01

    Nitrogen limits the productivity of most ecosystems, but can also cause environmental problems. With the increasing amount of sludge generated by better wastewater treatment, land application of pelletized sludge appears as a combined solution to waste disposal and plant nitrogen nutrition issues. Six types of sludge pellets/granules, containing different mixtures of sludge, ash and/or lime have been inoculated and incubated for 8 weeks at 20 deg C in the dark, to study N net mineralisation rates. Laboratory results showed no indication of general differences between sludge/ash and sludge/lime mixtures, with respect to N mineralisation and nitrification, but some differences between Umeaa pellets and GaevIe granules were discernible. The higher net N mineralisation rates in pellets appeared to be related to sludge properties. On the contrary pellets had a low level of nitrification, which might be explained by preliminary heat treatment of the sludge and the seemingly slow recolonization of nitrifiers. It is also believed that considerable amounts of N were lost, and that the major route for these losses was ammonia volatilisation. From an economical point of view, sludge pelletisation appears to be the most cost-effective means of disposal. It transforms sludge into a valuable, odourless and storable fertiliser or heat source. Some income could even be expected. The benefits obtained from an increased tree growth could justify forest fertilisation with pelletized sludge, but further research is needed to determine more precisely the possible growth increment and the consequences on the environment

  17. Reducing capacities and redox potentials of humic substances extracted from sewage sludge.

    Science.gov (United States)

    Yang, Zhen; Du, Mengchan; Jiang, Jie

    2016-02-01

    Humic substances (HS) are redox active organic materials that can be extracted from sewage sludge generated in wastewater treatment processes. Due to the poor understanding of reducing capacity, redox potentials and redox active functional groups of HS in sewage sludge, the potential contribution of sludge HS in transformation of wastewater contaminants is unclear. In the present study, the number of electrons donated or accepted by sewage sludge HS were quantified before and after reduction by iron compounds that possess different redox potentials and defined as the reducing capacity of the sewage sludge. In contrast to previous studies of soil and commercial humic acids (HA), reduced sludge HA showed a lower reducing capacity than that of native HA, which implies formation of semiquinone radicals since the semiquinone radical/hydroquinone pair has a much higher redox potential than the quinone/hydroquinone pair. It is novel that reducing capacities of sludge HA were determined in the redox potential range from -314 to 430 mV. The formation of semiquinone radicals formed during the reduction of quinone moieties in sludge HA is shown by three-dimensional excitation/emission matrix fluorescence spectroscopies information, increasing fluorescence intensities and blue-shifting of the excitation/emission peak of reduced sludge HA. Knowledge of sludge HS redox potentials and corresponding reducing capacities makes it possible to predict the transformation of redox active pollutants and facilitate manipulation and optimization of sludge loading wastewater treatment processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. A study on the dewatering of industrial waste sludge by fry-drying technology

    International Nuclear Information System (INIS)

    Ohm, Tae-In; Chae, Jong-Seong; Kim, Jeong-Eun; Kim, Hee-kyum; Moon, Seung-Hyun

    2009-01-01

    , lead, zinc, mercury, and cadmium. Most importantly, if the dried sludge is used as a solid fuel, these heavy metals can be collected from the dust collector after combustion.

  19. Biodegradation studies of oil sludge containing high hydrocarbons concentration

    International Nuclear Information System (INIS)

    Olguin-Lora, P.; Munoz-Colunga, A.; Castorena-Cortes, G.; Roldan-Carrillo, T.; Quej Ake, L.; Reyes-Avila, J.; Zapata-Penasco, I.; Marin-Cruz, J.

    2009-01-01

    Oil industry has a significant impact on environment due to the emission of, dust, gases, waste water and solids generated during oil production all the way to basic petrochemical product manufacturing stages. the aim of this work was to evaluate the biodegradation of sludge containing high hydrocarbon concentration originated by a petroleum facility. A sludge sampling was done at the oil residuals pool (ORP) on a gas processing center. (Author)

  20. Sewage sludges disinfection

    International Nuclear Information System (INIS)

    Alexandre, D.

    1977-01-01

    There is an hygienic risk in using biological sewage sludges for agriculture. Systematic analysis carried out on sludges samples obtained from purification plants in East and South part of France, show the almost uniform presence of pathogenic microorganisms. Some of it survive more than 9 months after soil application. Conventional process for disinfection: liming and heat are not suitable for agricultural use. On the other hand, irradiation involves no modification in structure and composition of sludges. Radiation doses required for disinfection vary according to microorganisms. If some of them are eliminated with rather light doses (200 krad) mycobacteria, viruses and eggs of worms resist to more important doses. Security dose is estimated around 1000 krad

  1. Energy potential of the modified excess sludge

    Science.gov (United States)

    Zawieja, Iwona

    2017-11-01

    On the basis of the SCOD value of excess sludge it is possible to estimate an amount of energy potentially obtained during the methane fermentation process. Based on a literature review, it has been estimated that from 1 kg of SCOD it is possible to obtain 3.48 kWh of energy. Taking into account the above methane and energy ratio (i.e. 10 kWh/1Nm3 CH4), it is possible to determine the volume of methane obtained from the tested sludge. Determination of potential energy of sludge is necessary for the use of biogas as a source of power generators as cogeneration and ensure the stability of this type of system. Therefore, the aim of the study was to determine the energy potential of excess sludge subjected to the thermal and chemical disintegration. In the case of thermal disintegration, test was conducted in the low temperature 80°C. The reagent used for the chemical modification was a peracetic acid, which in an aqueous medium having strong oxidizing properties. The time of chemical modification was 6 hours. Applied dose of the reagent was 1.0 ml CH3COOOH/L of sludge. By subjecting the sludge disintegration by the test methods achieved an increase in the SCOD value of modified sludge, indicating the improvement of biodegradability along with a concomitant increase in their energy potential. The obtained experimental production of biogas from disintegrated sludge confirmed that it is possible to estimate potential intensity of its production. The SCOD value of 2576 mg O2/L, in the case of chemical disintegration, was obtained for a dose of 1.0 ml CH3COOH/L. For this dose the pH value was equal 6.85. In the case of thermal disintegration maximum SCOD value was 2246 mg O2/L obtained at 80°C and the time of preparation 6 h. It was estimated that in case of thermal disintegration as well as for the chemical disintegration for selected parameters, the potential energy for model digester of active volume of 5L was, respectively, 0.193 and 0,118 kWh.

  2. Energy potential of the modified excess sludge

    Directory of Open Access Journals (Sweden)

    Zawieja Iwona

    2017-01-01

    Full Text Available On the basis of the SCOD value of excess sludge it is possible to estimate an amount of energy potentially obtained during the methane fermentation process. Based on a literature review, it has been estimated that from 1 kg of SCOD it is possible to obtain 3.48 kWh of energy. Taking into account the above methane and energy ratio (i.e. 10 kWh/1Nm3 CH4, it is possible to determine the volume of methane obtained from the tested sludge. Determination of potential energy of sludge is necessary for the use of biogas as a source of power generators as cogeneration and ensure the stability of this type of system. Therefore, the aim of the study was to determine the energy potential of excess sludge subjected to the thermal and chemical disintegration. In the case of thermal disintegration, test was conducted in the low temperature 80°C. The reagent used for the chemical modification was a peracetic acid, which in an aqueous medium having strong oxidizing properties. The time of chemical modification was 6 hours. Applied dose of the reagent was 1.0 ml CH3COOOH/L of sludge. By subjecting the sludge disintegration by the test methods achieved an increase in the SCOD value of modified sludge, indicating the improvement of biodegradability along with a concomitant increase in their energy potential. The obtained experimental production of biogas from disintegrated sludge confirmed that it is possible to estimate potential intensity of its production. The SCOD value of 2576 mg O2/L, in the case of chemical disintegration, was obtained for a dose of 1.0 ml CH3COOH/L. For this dose the pH value was equal 6.85. In the case of thermal disintegration maximum SCOD value was 2246 mg O2/L obtained at 80°C and the time of preparation 6 h. It was estimated that in case of thermal disintegration as well as for the chemical disintegration for selected parameters, the potential energy for model digester of active volume of 5L was, respectively, 0.193 and 0,118 kWh.

  3. Combustion chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  4. Fuzzy control for the operation of an electrical energy generation system based on standard fuel cells PEM; Control difuso para la operacion de un sistema de generacion de energia electrica basado en celdas de combustible tipo PEM

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez R, Miguel; Gutierrez A, Ruben [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Rodriguez P, Alejandro [Centro Nacional de Investigacion y Desarrollo Tecnologico (Cenidet), Cuernavaca, Morelos (Mexico)

    2005-07-01

    Fuel cells, as totally clean power plants, have many applications in the industry in general, in the transport system, in the electricity generation for domestic consumption and in the communication systems, among others. When developing new forms of generation with renewable energy sources, it must be considered that petroleum will stop in being an available power resource. The interest in the study of the fuel cells has been increased in the last years because it is considered a solution to the supply of distributed energy problem. Therefore, already exist research institutions that are developing work on this technology. A generation of electrical energy system based on fuel cells is a nonlinear system where the control of the variables of the process, such as the temperature of the system and the pressurization of the reactants, are an important aspect for its proper operation, since it influences in the water balance and therefore in the global efficiency of the system. [Spanish] Las celdas de combustible, como fuente de energia totalmente limpia, tienen muchas aplicaciones en la industria en general: en el sistema de transporte, en la generacion de electricidad para consumo domestico y en los sistemas de comunicacion, entre otros. Al desarrollar nuevas formas de generacion con fuentes de energia renovables, se debe considerar que el petroleo dejara de ser un recurso energetico disponible. El interes en el estudio de las celdas de combustible se ha incrementado en los ultimos anos debido a que se le considera una solucion al problema de abasto de energia distribuida. Por lo tanto, ya existen instituciones de investigacion que estan desarrollando trabajos sobre esta tecnologia. Un sistema de generacion de energia electrica basado en celdas de combustible es un sistema no lineal en donde el control de las variables del proceso, tales como la temperatura del sistema y la presurizacion de los reactantes, es un aspecto importante para su buen funcionamiento, ya que

  5. Analysis of Combined Power and Refrigeration Generation Using the Carbon Dioxide Thermodynamic Cycle to Recover the Waste Heat of an Internal Combustion Engine

    OpenAIRE

    Shunsen Wang; Kunlun Bai; Yonghui Xie; Juan Di; Shangfang Cheng

    2014-01-01

    A novel thermodynamic system is proposed to recover the waste heat of an internal combustion engine (ICE) by integrating the transcritical carbon dioxide (CO2) refrigeration cycle with the supercritical CO2 power cycle, and eight kinds of integration schemes are developed. The key parameters of the system are optimized through a genetic algorithm to achieve optimum matching with different variables and schemes, as well as the maximum net power output (Wnet). The results indicate that replacin...

  6. Characterisation of wood combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto

    The combustion of wood chips and wood pellets for the production of renewable energy in Denmark increased from 5.7 PJ to 16 PJ during the period 2000-2015, and further increases are expected to occur within the coming years. In 2012, about 22,300 tonnes of wood ashes were generated in Denmark....... Currently, these ashes are mainly landfilled, despite Danish legislation allowing their application onto forest and agricultural soils for fertilising and/or liming purposes. During this PhD work, 16 wood ash samples generated at ten different Danish combustion plants were collected and characterised...... for their composition and leaching properties. Despite the relatively large variations in the contents of nutrients and trace metals, the overall levels were comparable to typical ranges reported in the literature for other wood combustion ashes, as well as with regards to leaching. In general, the composition...

  7. Evaluation of sludge management alternatives in Istanbul metropolitan area.

    Science.gov (United States)

    Cakmakci, M; Erdim, E; Kinaci, C; Akca, L

    2005-01-01

    The main concern of this paper was to predict the sludge quantities generated from 18 wastewater treatment plants, which were stated to be established in the "Istanbul Water Supply, Sewerage and Drainage, Sewage Treatment and Disposal Master Plan", 10 of which are in operation at present. Besides this, obtaining the required data to compare various treatment schemes was another goal of the study. Especially, the estimation of the sludge quantity in the case of enhanced primary sedimentation was of importance. Wastewater sludge management strategies were discussed in order to develop suggestions for Istanbul Metropolitan city. Within this context, the wastewater treatment facilities, mentioned in the Master Plan that had been completed by 2000, were evaluated in terms of sludge production rates, locations and technical and management aspects. Disposal alternatives of the wastewater treatment sludge were also evaluated in this study. Using of the dewatered sludge as a landfill cover material seems the best alternative usage. Up to the year of 2040, the requirement of cover material for landfills in Istanbul will be met by the dewatered sludge originated from wastewater treatment plants in the region.

  8. Application of radiation technology to sewage sludge processing: A review

    International Nuclear Information System (INIS)

    Wang Jianlong; Wang Jiazhuo

    2007-01-01

    Sewage sludge is unwanted residual solid wastes generated in wastewater treatment and its management is one of the most critical environmental issues of today. The treatment and disposal of sludge contribute a considerable proportion of the cost for running a wastewater treatment plant. The increasing amount of swage sludge and more and more legislative regulation of its disposal have stimulated the need for developing new technologies to process sewage sludge efficiently and economically. One ideal consideration is to recycle it after proper treatment. Radiation technology is regarded to be a promising alternative for its high efficiency in pathogen inactivation, organic pollutants oxidation, odor nuisance elimination and some other characteristics enhancement, which will facilitate the down-stream process of sludge treatment and disposal. Here we present a brief review of application of radiation technology on sewage sludge processing. Some basic information of two currently available irradiation systems and fundamental radiation chemistry are introduced firstly; then the world-wide application of this promising technology is reviewed; various effects of radiation on sludge is discussed in detail; and some concluding remarks are given and some future directions are also proposed

  9. Possibility of radiation application to sludge treatment in Japan

    International Nuclear Information System (INIS)

    Takehisa, Masaaki

    1980-01-01

    Interest in the effective use of sludge, which is generated increasingly with the propagation of sewerage, is being enhanced in Japan. On the other hand, attention is given to the return of sludge to soil in agriculture for the purpose of putting organic material into agricultural land. For this purpose, of course heavy metals and toxic chemicals must not be contained in sludge, but further inactivation of the pathogens, parasite ova and seeds in sludge is considered to be required. Japan Atomic Energy Research Institute investigated the radiation disinfection of dehydrated cake forming 80% of the sludge taken out of treatment plants in Japan. As a result of the examination of the change in the number of bacteria by γ irradiation, 0.5 Mrad was decided to be the suitable dose for sanitating sludge regardless of season, at which coliform group decreased greatly. It seems that sludges are required to be composted in Japan. Radiation disinfection has the advantage of composting under the optimum temperature condition for fermentation, because it is not required to keep high temperature during fermentation aiming at the sterilization of pathogens. However, it is desirable to use large output accelerators combining with the radiation process for the purpose of reusing treated water in order to reduce the process cost. (Wakatsuki, Y.)

  10. General Vision of Phytoremediation Treatment for Sludge Derived of Wastewater

    Directory of Open Access Journals (Sweden)

    Yanneth Parra Martínez

    2011-04-01

    Full Text Available Wastewater coming from industrial processes requires special treatment either physical and/or biological. Their resulting problem is the sludge being produced, whose components are mainly inorganic with some organic content, and in the most unfavorable case, with the inclusion of toxic contents, i.e. heavy metals. In certain industries, the problem has to do with the accumulation of sludge in containers, before being disposed of in an appropriate way. However, sludge disposal by other non-environmentalist industries is carried out directly to the sewer or even, to water bodies. For developing this project, the water and soil pollution scope was taken into account, together with the poor disposal of sludge generated from wastewater treatment plants; hence, sludge with high heavy metal content and other pollutants coming from three wastewater treatment plants were characterized and treated: the first one, coming from an automobile industry; the second one, from a dairy industry (sludge with organic and fat content; and a third group coming from a municipality. When comparing the results of these analysis with the Colombian standards ( Decree 1594 of 1984, a higher pollution content was found. Therefore, a phytoremediation treatment was achieved with two species of microphytes. During the development of this process, pollutant migration was observed from the sludge toward one of the parts of the microphyte. Effectiveness of the process was tested for the removal of pollutants of sanitary interest: for example, cyanide, phenols, zinc, and nickel.

  11. Numerical investigation of biogas flameless combustion

    International Nuclear Information System (INIS)

    Hosseini, Seyed Ehsan; Bagheri, Ghobad; Wahid, Mazlan Abdul

    2014-01-01

    Highlights: • Fuel consumption decreases from 3.24 g/s in biogas conventional combustion to 1.07 g/s in flameless mode. • The differences between reactants and products temperature intensifies irreversibility in traditional combustion. • The temperature inside the chamber is uniform in biogas flameless mode and exergy loss decreases in this technique. • Low O 2 concentration in the flameless mode confirms a complete and quick combustion process in flameless regime. - Abstract: The purpose of this investigation is to analyze combustion characteristics of biogas flameless mode based on clean technology development strategies. A three dimensional (3D) computational fluid dynamic (CFD) study has been performed to illustrate various priorities of biogas flameless combustion compared to the conventional mode. The effects of preheated temperature and wall temperature, reaction zone and pollutant formation are observed and the impacts of combustion and turbulence models on numerical results are discussed. Although preheated conventional combustion could be effective in terms of fuel consumption reduction, NO x formation increases. It has been found that biogas is not eligible to be applied in furnace heat up due to its low calorific value (LCV) and it is necessary to utilize a high calorific value fuel to preheat the furnace. The required enthalpy for biogas auto-ignition temperature is supplied by enthalpy of preheated oxidizer. In biogas flameless combustion, the mean temperature of the furnace is lower than traditional combustion throughout the chamber. Compared to the biogas flameless combustion with uniform temperature, very high and fluctuated temperatures are recorded in conventional combustion. Since high entropy generation intensifies irreversibility, exergy loss is higher in biogas conventional combustion compared to the biogas flameless regime. Entropy generation minimization in flameless mode is attributed to the uniform temperature inside the chamber

  12. Experimental studies on pulp and paper mill sludge ash behavior in fluidized bed combustors

    Energy Technology Data Exchange (ETDEWEB)

    Latva-Somppi, J. [VTT Chemical Technology, Espoo (Finland). Process Technology

    1998-11-01

    Ash formation during the fluidized bed combustion (FBC) of pulp and paper mill sludges has been experimentally studied on an industrial and bench scale. The methods included aerosol measurements, chemical and crystalline composition analyses, thermogravimetry and electron microscopy. Fly ash mass and number size distributions and elemental enrichment in submicron particles and bottom ash were measured. Fly ash, bottom ash and ash deposits were characterized and their formation mechanisms are discussed. During combustion the fine paper-making additives in sludge, clay minerals and calcite, sintered fanning porous agglomerates. The fly ash mass mean size was 7.5 - 15 lam and the supermicron particles included 93.6 - 97.3 % of the fly ash. Condensation of the volatilized inorganic species formed spherical submicron particles in the fly ash. Their mass concentration was almost negligible when co-firing paper mill sludges and wood. This suggests that the fraction of the volatilized inorganic species in the paper mill sludges was low. Results from pulp mill sludge and bark co-firing were different. A clear mass mode below 0.3 pm, presenting 2.2 - 5.0 weight-% of the fly ash was detected. The condensed species included K, Na, S and Cl. Their mass fraction was higher in the pulp mill sludge than in the paper mill sludge. Evidently this resulted in increased volatilization and formation of condensed particles. The following trace elements were enriched in the submicron ash during pulp mill sludge and wood co-firing: As, Cd, Rb and Pb. The main part of the volatile species was, however, captured in the bulk ash. Presumably, this was due to the high surface area concentration in the bulk ash. Sludge moisture was observed to reduce the inorganic species volatilization. Probably steam vaporization from the wet sludge through the burning layer decreased combustion temperatures on char surface and less char was produced. Hence, the volatilization of ash forming species was

  13. Symposium /International/ on Combustion, 18th, University of Waterloo, Waterloo, Ontario, Canada, August 17-22, 1980, Proceedings

    Science.gov (United States)

    1981-01-01

    Problems related to combustion generated pollution are explored, taking into account the mechanism of NO formation from nitrogen compounds in hydrogen flames studied by laser fluorescence, the structure and similarity of nitric oxide production in turbulent diffusion flames, the effect of steam addition on NO formation, and the formation of NO2 by laminar flames. Other topics considered are concerned with propellant combustion, fluidized bed combustion, the combustion of droplets and sprays, premixed flame studies, fire studies, and flame stabilization. Attention is also given to coal flammability, chemical kinetics, turbulent combustion, soot, coal combustion, the modeling of combustion processes, combustion diagnostics, detonations and explosions, ignition, internal combustion engines, combustion studies, and furnaces.

  14. Application of Hydrothermal Treatment to High Concentrated Sewage Sludge for Anaerobic Digestion Process

    OpenAIRE

    M. Orikawa; H. Kamahara; Y. Atsuta; H. Daimon

    2013-01-01

    Tomato and seaweed were produced by utilizing CO2 and heat discharged from power generation using biogas in Toyogawa biomass park, Japan. The biogas was obtained by anaerobic digestion with hydrothermal treatment. The hydrothermal treatment was applied to the high concentrated sewage sludge (22 % total solids (TS) dewatered sludge). The purpose of this study is to clarify the effect of hydrothermal treatment on the qualities of high concentrated sewage sludge, by analyzing particulate organic...

  15. A review on sewage sludge (Biosolids) a resource for sustainable agriculture

    OpenAIRE

    Kumar, V., Chopra, A.K. and Kumar, A.

    2017-01-01

    Sewage sludge (Biosolids) generation is fastly increasing resulting from the regular increase of population, urban planning and industrial developments worldwide. The sludge needs to be adequately treated and environmentally managed to reduce the negative impacts of its application or disposal. The present review deals with the different applications of sewage sludge for sustainable agriculture. The scattered literature is harnessed to critically review the uses of biosolids to promote sustai...

  16. Composting sewage sludge

    International Nuclear Information System (INIS)

    Epstein, E.

    1979-01-01

    Sewage sludge is predominantly organic matter containing domestic and industrial wastes. The inefficiency of the waste water treatment to destroy pathogens and stabilization of odor-producing volatile organic compounds necessitates further treatment before sludge can be used as a soil amendment or fertilizer. Composting, which is the rapid biological decomposition of the sludge organic matter is an excellent method of sludge stabilization. During the process, volatile organics are decomposed and many of the pathogens destoyed. The low cost of the process and its flexibility with respect to labor and capital makes the system highly attractive to municipalities. A major problem facing large urban waste water treatment facilities is the distribution or marketing. The light weight of the material, expensive hauling costs, and low fertilizer value reduce its attractiveness to the agricultural sector. Thus, the greatest market is for horticultural purposes, sod, nurseries, greenhouses, parks, and reclamation areas. The major potential benefits of irradiating compost as a means of further disinfection are: (1) elimination of any health hazard; (2) increase of market potential, i.e., providing more market outlets to distribute the material; (3) compliance with state and federal health regulations; and (4) enhancement of the economics of composting as a result of utilizing compost in speciality products commanding a higher value

  17. Bacteriology of activated sludge

    NARCIS (Netherlands)

    Gils, van H.W.

    1964-01-01

    The bacteriology and biochemistry of activated sludge grown in domestic waste water or fed with synthetic media were studied. The nature of the flocs was investigated by determining morphological and physiological characteristics of many strains isolated.

    Predominant bacteria were

  18. Leaching from biomass combustion ash

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard

    2014-01-01

    The use of biomass combustion ashes for fertilizing and liming purposes has been widely addressed in scientific literature. Nevertheless, the content of potentially toxic compounds raises concerns for a possible contamination of the soil. During this study five ash samples generated at four...

  19. Oxygen-enhanced combustion

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Combustion technology has traditionally been dominated by air/fuel combustion. However, two developments have increased the significance of oxygen-enhanced combustion-new technologies that produce oxygen less expensively and the increased importance of environmental regulations. Advantages of oxygen-enhanced combustion include less pollutant emissions as well as increased energy efficiency and productivity. Oxygen-Enhanced Combustion, Second Edition compiles information about using oxygen to enhance industrial heating and melting processes. It integrates fundamental principles, applications, a

  20. Sewage sludge treatment system

    Science.gov (United States)

    Kalvinskas, John J. (Inventor); Mueller, William A. (Inventor)

    1976-01-01

    Raw sewage may be presently treated by mixing screened raw sewage with activated carbon. The mixture is then allowed to stand in a first tank for a period required to settle the suspended matter to the bottom of the tank as a sludge. Thereafter, the remaining liquid is again mixed with activated carbon and the mixture is transferred to a secondary settling tank, where it is permitted to stand for a period required for the remaining floating material to settle as sludge and for adsorption of sewage carbon as well as other impurities to take place. The sludge from the bottom of both tanks is removed and pyrolyzed to form activated carbon and ash, which is mixed with the incoming raw sewage and also mixed with the liquid being transferred from the primary to the secondary settling tank. It has been found that the output obtained by the pyrolysis process contains an excess amount of ash. Removal of this excess amount of ash usually also results in removing an excess amount of carbon thereby requiring adding carbon to maintain the treatment process. By separately pyrolyzing the respective sludges from the first and second settling tanks, and returning the separately obtained pyrolyzed material to the respective first and second tanks from which they came, it has been found that the adverse effects of the excessive ash buildup is minimized, the carbon yield is increased, and the sludge from the secondary tank can be pyrolyzed into activated carbon to be used as indicated many more times than was done before exhaustion occurs.

  1. Harvesting biogas from wastewater sludge and food waste

    International Nuclear Information System (INIS)

    Chua, K H; Cheah, W L; Leong, Y P; Tan, C F

    2013-01-01

    Wastewater sludge and food waste are good source of biogas. Anaerobic treatment of slude and food waste able to produce biogas which is a potential renewable energy source. This study looks into the potential biogas generation and the effects of temperature on biogas generation. A lab scale reactor was used to simulate the biogas generation. The results show that wastewater sludge able to produced upto 44.82 ml biogas/kg of sludge. When mixed with food waste at a ratio of 30:70 (food waste), the biogas generated were 219.07 ml/kg of waste. Anaerobic of food waste alone produced biogas amount to 59.75 ml/kg of food waste. Anaerobic treatment also reduces the volume of waste. The effect of temperature shows that higher temperature produces more biogas than lower temperature.

  2. Effect of hydrothermal treatment temperature on the properties of sewage sludge derived solid fuel

    Directory of Open Access Journals (Sweden)

    Mi Yan

    2015-10-01

    Full Text Available High moisture content along with poor dewaterability are the main challenges for sewage sludge treatment and utilization. In this study, the effect of hydrothermal treatment at various temperature (120-200 ˚C on the properties of sewage sludge derived solid fuel was investigated in the terms of mechanical dewatering character, drying character, calorific value and heavy metal distribution. Hydrothermal treatment (HT followed by dewatering process significantly reduced moisture content and improved calorific value of sewage sludge with the optimum condition obtained at 140˚C. No significant alteration of drying characteristic was produced by HT. Heavy metal enrichment in solid particle was found after HT that highlighted the importance of further study regarding heavy metal behavior during combustion. However, it also implied the potential application of HT on sewage sludge for heavy metal removal from wastewater.

  3. Simulation of co-incineration of sewage sludge with municipal solid waste in a grate furnace incinerator.

    Science.gov (United States)

    Lin, Hai; Ma, Xiaoqian

    2012-03-01

    Incineration is one of the most important methods in the resource recovery disposal of sewage sludge. The combustion characteristics of sewage sludge and an increasing number of municipal solid waste (MSW) incineration plants provide the possibility of co-incineration of sludge with MSW. Computational fluid dynamics (CFD) analysis was used to verify the feasibility of co-incineration of sludge with MSW, and predict the effect of co-incineration. In this study, wet sludge and semi-dried sludge were separately blended with MSW as mixed fuels, which were at a co-incineration ratios of 5 wt.% (wet basis, the same below), 10 wt.%, 15 wt.%, 20 wt.% and 25 wt.%. The result indicates that co-incineration of 10 wt.% wet sludge with MSW can ensure the furnace temperature, the residence time and other vital items in allowable level, while 20 wt.% of semi-dried sludge can reach the same standards. With lower moisture content and higher low heating value (LHV), semi-dried sludge can be more appropriate in co-incineration with MSW in a grate furnace incinerator. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Thermal power sludge – properties, treatment, utilization

    Directory of Open Access Journals (Sweden)

    Martin Sisol

    2005-11-01

    Full Text Available In this paper a knowledge about properties of thermal power sludge from coal combustion in smelting boilers is presented. The physical and technological properties of slag – granularity, density, specific, volume and pouring weight, hardness and decoupling – together with chemical properties influence its exploitation. The possibility of concentrating the Fe component by the mineral processing technologies (wet low-intenzity magnetic separation is verified. An industrial use of the slag in civil engineering, e.g. road construction, was realised. The slag-fly ashes are directly utilized in the cement production as a substitute of a part of natural raw materials. For the use of slag as the stoneware in the road construction, all the criteria are fulfilled.

  5. Disposing of coal combustion residues in inactive surface mines: Effects on water quality

    International Nuclear Information System (INIS)

    Kim, A.G.; Ackman, T.E.

    1994-01-01

    The disposal of coal combustion residues (CCR) in surface and underground coal mines can provide a stable, low-maintenance alternative to landfills, benefiting the mining and electric power industries. The material may be able to improve water quality at acid generating abandoned or reclaimed coal mine sites. Most combustion residues are alkaline, and their addition to the subsurface environment could raise the pH, limiting the propagation of pyrite oxidizing bacteria and reducing the rate of acid generation. Many of these CCR are also pozzolanic, capable of forming cementitious grouts. Grouts injected into the buried spoil may decrease its permeability and porosity, diverting water away from the pyritic material. Both mechanisms, alkaline addition and water diversion, are capable of reducing the amount of acid produced at the disposal site. The US Bureau of Mines is cooperating in a test of subsurface injection of CCR into a reclaimed surface mine. Initially, a mixture of fly ash, lime, and acid mine drainage (AMD) sludge was injected. Lime was the source of calcium for the formation of the pozzolanic grout. Changes in water quality parameters (pH, acidity, anions, and trace metals) in water samples from wells and seeps indicate a small but significant improvement after CCR injection. Changes in the concentration of heavy metals in the water flowing across the site were apparently influenced by the presence of flyash

  6. Life cycle assessment of sewage sludge co-incineration in a coal-based power station.

    Science.gov (United States)

    Hong, Jingmin; Xu, Changqing; Hong, Jinglan; Tan, Xianfeng; Chen, Wei

    2013-09-01

    A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. STP-ECRTS - THERMAL AND GAS ANALYSES FOR SLUDGE TRANSPORT AND STORAGE CONTAINER (STSC) STORAGE AT T PLANT

    Energy Technology Data Exchange (ETDEWEB)

    CROWE RD; APTHORPE R; LEE SJ; PLYS MG

    2010-04-29

    The Sludge Treatment Project (STP) is responsible for the disposition of sludge contained in the six engineered containers and Settler tank within the 105-K West (KW) Basin. The STP is retrieving and transferring sludge from the Settler tank into engineered container SCS-CON-230. Then, the STP will retrieve and transfer sludge from the six engineered containers in the KW Basin directly into a Sludge Transport and Storage Containers (STSC) contained in a Sludge Transport System (STS) cask. The STSC/STS cask will be transported to T Plant for interim storage of the STSC. The STS cask will be loaded with an empty STSC and returned to the KW Basin for loading of additional sludge for transportation and interim storage at T Plant. CH2MHILL Plateau Remediation Company (CHPRC) contracted with Fauske & Associates, LLC (FAI) to perform thermal and gas generation analyses for interim storage of STP sludge in the Sludge Transport and Storage Container (STSCs) at T Plant. The sludge types considered are settler sludge and sludge originating from the floor of the KW Basin and stored in containers 210 and 220, which are bounding compositions. The conditions specified by CHPRC for analysis are provided in Section 5. The FAI report (FAI/10-83, Thermal and Gas Analyses for a Sludge Transport and Storage Container (STSC) at T Plant) (refer to Attachment 1) documents the analyses. The process considered was passive, interim storage of sludge in various cells at T Plant. The FATE{trademark} code is used for the calculation. The results are shown in terms of the peak sludge temperature and hydrogen concentrations in the STSC and the T Plant cell. In particular, the concerns addressed were the thermal stability of the sludge and the potential for flammable gas mixtures. This work was performed with preliminary design information and a preliminary software configuration.

  8. Air Emission Reduction Benefits of Biogas Electricity Generation at Municipal Wastewater Treatment Plants.

    Science.gov (United States)

    Gingerich, Daniel B; Mauter, Meagan S

    2018-02-06

    Conventional processes for municipal wastewater treatment facilities are energy and materially intensive. This work quantifies the air emission implications of energy consumption, chemical use, and direct pollutant release at municipal wastewater treatment facilities across the U.S. and assesses the potential to avoid these damages by generating electricity and heat from the combustion of biogas produced during anaerobic sludge digestion. We find that embedded and on-site air emissions from municipal wastewater treatment imposed human health, environmental, and climate (HEC) damages on the order of $1.63 billion USD in 2012, with 85% of these damages attributed to the estimated consumption of 19 500 GWh of electricity by treatment processes annually, or 0.53% of the US electricity demand. An additional 11.8 million tons of biogenic CO 2 are directly emitted by wastewater treatment and sludge digestion processes currently installed at plants. Retrofitting existing wastewater treatment facilities with anaerobic sludge digestion for biogas production and biogas-fueled heat and electricity generation has the potential to reduce HEC damages by up to 24.9% relative to baseline emissions. Retrofitting only large plants (>5 MGD), where biogas generation is more likely to be economically viable, would generate HEC benefits of $254 annually. These findings reinforce the importance of accounting for use-phase embedded air emissions and spatially resolved marginal damage estimates when designing sustainable infrastructure systems.

  9. The fuel cells: Truths on the generation of clean and efficient electricity electrochemical way; Las celdas de combustible: Verdades sobre la generacion de electricidad limpia y eficiente via electroquimica

    Energy Technology Data Exchange (ETDEWEB)

    Cano Castillo, Ulises [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    1999-07-01

    In the search of alternative technologies for the generation of electrical energy, the Instituto de Investigaciones Electricas (IIE) has put special attention in a technology that promises to be key in the next years: The fuel cells, it is for this reason that in this article a review of this type of cells is presented, as well as its basic characteristics and benefits as a result of its use for the generation of electrical energy. [Spanish] En la busqueda de tecnologias alternativas de generacion de energia electrica, el Instituto de Investigaciones Electricas (IIE) ha puesto atencion especial en una tecnologia que promete ser clave en los proximos anos: Las celdas de combustible, es por ello que en este articulo se presenta una resena de este tipo de celdas, asi como sus caracteristicas principales y beneficios como resultado de su utilizacion para la generacion de energia electrica.

  10. Analysis of Combined Power and Refrigeration Generation Using the Carbon Dioxide Thermodynamic Cycle to Recover the Waste Heat of an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Shunsen Wang

    2014-01-01

    Full Text Available A novel thermodynamic system is proposed to recover the waste heat of an internal combustion engine (ICE by integrating the transcritical carbon dioxide (CO2 refrigeration cycle with the supercritical CO2 power cycle, and eight kinds of integration schemes are developed. The key parameters of the system are optimized through a genetic algorithm to achieve optimum matching with different variables and schemes, as well as the maximum net power output (Wnet. The results indicate that replacing a single-turbine scheme with a double-turbine scheme can significantly enhance the net power output (Wnet and lower the inlet pressure of the power turbine (P4. With the same exhaust parameters of ICE, the maximum Wnet of the double-turbines scheme is 40%–50% higher than that of the single-turbine scheme. Replacing a single-stage compression scheme with a double-stage compression scheme can also lower the value of P4, while it could not always significantly enhance the value of Wnet. Except for the power consumption of air conditioning, the net power output of this thermodynamic system can reach up to 13%–35% of the engine power when it is used to recover the exhaust heat of internal combustion engines.

  11. Effect of small proportion of butanol additive on the performance, emission, and combustion of Australian native first- and second-generation biodiesel in a diesel engine.

    Science.gov (United States)

    Rahman, Md Mofijur; Rasul, Mohammad Golam; Hassan, Nur Md Sayeed; Azad, Abul Kalam; Uddin, Md Nasir

    2017-10-01

    This paper aims to investigate the effect of the addition of 5% alcohol (butanol) with biodiesel-diesel blends on the performance, emissions, and combustion of a naturally aspirated four stroke multi-cylinder diesel engine at different engine speeds (1200 to 2400 rpm) under full load conditions. Three types of local Australian biodiesel, namely macadamia biodiesel (MB), rice bran biodiesel (RB), and waste cooking oil biodiesel (WCB), were used for this study, and the data was compared with results for conventional diesel fuel (B0). Performance results showed that the addition of butanol with diesel-biodiesel blends slightly lowers the engine efficiency. The emission study revealed that the addition of butanol additive with diesel-biodiesel blends lowers the exhaust gas temperature (EGT), carbon monoxide (CO), nitrogen oxide (NOx), and particulate matter (PM) emissions whereas it increases hydrocarbon (HC) emissions compared to B0. The combustion results indicated that in-cylinder pressure (CP) for additive added fuel is higher (0.45-1.49%), while heat release rate (HRR) was lower (2.60-9.10%) than for B0. Also, additive added fuel lowers the ignition delay (ID) by 23-30% than for B0. Finally, it can be recommended that the addition of 5% butanol with Australian biodiesel-diesel blends can significantly lower the NOx and PM emissions.

  12. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlândia-MG, Brazil

    International Nuclear Information System (INIS)

    Oliveira Silva, Jader de; Filho, Guimes Rodrigues; Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Júlia Graciele; Vieira da Silva, Cleuzilene; Alves Cerqueira, Daniel

    2012-01-01

    Highlights: ► In this study, the sludge was characterized by thermal analyses and FTIR. ► The superior calorific value of the sludge was 16.2 MJ kg −1 . ► The sludge showed a significant biodegradable portion of 65%. ► The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlândia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg −1 was found, which is within the range of values reported in the literature.

  13. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlandia-MG, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Silva, Jader de [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Departamento Municipal de Agua e Esgoto de Uberlandia (DMAE) (Brazil); Filho, Guimes Rodrigues, E-mail: guimes@ufu.br [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Julia Graciele [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Vieira da Silva, Cleuzilene [Faculdade de Engenharia Quimica da Universidade Federal de Uberlandia (Brazil); Alves Cerqueira, Daniel [Instituto de Ciencias Ambientais e Desenvolvimento Sustentavel da Universidade Federal da Bahia (Brazil)

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer In this study, the sludge was characterized by thermal analyses and FTIR. Black-Right-Pointing-Pointer The superior calorific value of the sludge was 16.2 MJ kg{sup -1}. Black-Right-Pointing-Pointer The sludge showed a significant biodegradable portion of 65%. Black-Right-Pointing-Pointer The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlandia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg{sup -1} was found, which is within the range of values reported in the literature.

  14. The John Zink Hamworthy combustion handbook

    CERN Document Server

    Baukal, Charles E

    2013-01-01

    Despite the length of time it has been around, its importance, and vast amounts of research, combustion is still far from being completely understood. Issues regarding the environment, cost, and fuel consumption add further complexity, particularly in the process and power generation industries. Dedicated to advancing the art and science of industrial combustion, The John Zink Hamworthy Combustion Handbook, Second Edition: Volume 3 - Applications offers comprehensive, up-to-date coverage of equipment used in the process and power generation industries. Under the leadership of Charles E. Baukal

  15. Combustion 2000

    Energy Technology Data Exchange (ETDEWEB)

    A. Levasseur; S. Goodstine; J. Ruby; M. Nawaz; C. Senior; F. Robson; S. Lehman; W. Blecher; W. Fugard; A. Rao; A. Sarofim; P. Smith; D. Pershing; E. Eddings; M. Cremer; J. Hurley; G. Weber; M. Jones; M. Collings; D. Hajicek; A. Henderson; P. Klevan; D. Seery; B. Knight; R. Lessard; J. Sangiovanni; A. Dennis; C. Bird; W. Sutton; N. Bornstein; F. Cogswell; C. Randino; S. Gale; Mike Heap

    2001-06-30

    . To achieve these objectives requires a change from complete reliance of coal-fired systems on steam turbines (Rankine cycles) and moving forward to a combined cycle utilizing gas turbines (Brayton cycles) which offer the possibility of significantly greater efficiency. This is because gas turbine cycles operate at temperatures well beyond current steam cycles, allowing the working fluid (air) temperature to more closely approach that of the major energy source, the combustion of coal. In fact, a good figure of merit for a HIPPS design is just how much of the enthalpy from coal combustion is used by the gas turbine. The efficiency of a power cycle varies directly with the temperature of the working fluid and for contemporary gas turbines the optimal turbine inlet temperature is in the range of 2300-2500 F (1260-1371 C). These temperatures are beyond the working range of currently available alloys and are also in the range of the ash fusion temperature of most coals. These two sets of physical properties combine to produce the major engineering challenges for a HIPPS design. The UTRC team developed a design hierarchy to impose more rigor in our approach. Once the size of the plant had been determined by the choice of gas turbine and the matching steam turbine, the design process of the High Temperature Advanced Furnace (HITAF) moved ineluctably to a down-fired, slagging configuration. This design was based on two air heaters: one a high temperature slagging Radiative Air Heater (RAH) and a lower temperature, dry ash Convective Air Heater (CAH). The specific details of the air heaters are arrived at by an iterative sequence in the following order:-Starting from the overall Cycle requirements which set the limits for the combustion and heat transfer analysis-The available enthalpy determined the range of materials, ceramics or alloys, which could tolerate the temperatures-Structural Analysis of the designs proved to be the major limitation-Finally the commercialization

  16. Reduced Chemical Kinetic Mechanisms for JP-8 Combustion

    National Research Council Canada - National Science Library

    Montgomery, Christopher J; Cannon, S. M; Mawid, M. A; Sekar, B

    2002-01-01

    Using CARM (Computer Aided Reduction Method), a computer program that automates the mechanism reduction process, six different reduced chemical kinetic mechanisms for JP-8 combustion have been generated...

  17. K Basins sludge removal temporary sludge storage tank system

    Energy Technology Data Exchange (ETDEWEB)

    Mclean, M.A.

    1997-06-12

    Shipment of sludge from the K Basins to a disposal site is now targeted for August 2000. The current path forward for sludge disposal is shipment to Tank AW-105 in the Tank Waste Remediation System (TWRS). Significant issues of the feasibility of this path exist primarily due to criticality concerns and the presence of polychlorinated biphenyls (PCBS) in the sludge at levels that trigger regulation under the Toxic Substance Control Act. Introduction of PCBs into the TWRS processes could potentially involve significant design and operational impacts to both the Spent Nuclear Fuel and TWRS projects if technical and regulatory issues related to PCB treatment cannot be satisfactorily resolved. Concerns of meeting the TWRS acceptance criteria have evolved such that new storage tanks for the K Basins sludge may be the best option for storage prior to vitrification of the sludge. A reconunendation for the final disposition of the sludge is scheduled for June 30, 1997. To support this decision process, this project was developed. This project provides a preconceptual design package including preconceptual designs and cost estimates for the temporary sludge storage tanks. Development of cost estimates for the design and construction of sludge storage systems is required to help evaluate a recommendation for the final disposition of the K Basin sludge.

  18. Minimization of Excess Sludge in Activated Sludge Systems

    Directory of Open Access Journals (Sweden)

    Sayed Ali Reza Momeni

    2006-01-01

    Full Text Available The disposal of excess sludge from wastewater treatment plant represents a rising challenge in activated sludge processes. Hence, the minimization of excess sludge production was investigated by increasing the dissolved oxygen in aeration basin. Units of the pilot include: Primary sedimentation tank, aeration basin, secondary sedimentation tank, and return sludge tank. Volume of aeration basin is 360 l and influent flow rate is 90 L/h. Influent of pilot is taken from effluent of grit chamber of Isfahan's North Wastewater treatment plant. The experiments were done on different parts of pilot during the 5 month of study. Results show that increase of dissolved oxygen in aeration tank affect on decrease of excess sludge. Increase of dissolved oxygen from 0.5 to 4.5 mg/L resulted in 25% decrease of excess sludge. Variation of dissolved oxygen affect on settleability of sludge too. By increase of dissolved oxygen, SVI decreased and then increased. Value of 1-3 mg/L was the adequate range of dissolved oxygen by settleability of sludge and optimum range was 2-2.5 mg/L. It could be concluded by increasing of dissolved oxygen up to of 3 mg/L, sludge settleability significant decreased.

  19. Agricultural yields of irradiated sewage sludge

    International Nuclear Information System (INIS)

    Magnavacca, Cecilia; Miranda, E.; Sanchez, M.

    1999-01-01

    Lettuce, radish and ryegrass have been used to study the nitrogen fertilization of soil by sewage sludge. The results show that the irradiated sludge improve by 15 - 30 % the production yield, compared to the non-irradiated sludge. (author)

  20. Reduced NOX combustion method

    International Nuclear Information System (INIS)

    Delano, M.A.

    1991-01-01

    This patent describes a method for combusting fuel and oxidant to achieve reduced formation of nitrogen oxides. It comprises: It comprises: heating a combustion zone to a temperature at least equal to 1500 degrees F.; injecting into the heated combustion zone a stream of oxidant at a velocity within the range of from 200 to 1070 feet per second; injecting into the combustion zone, spaced from the oxidant stream, a fuel stream at a velocity such that the ratio of oxidant stream velocity to fuel stream velocity does not exceed 20; aspirating combustion gases into the oxidant stream and thereafter intermixing the aspirated oxidant stream and fuel stream to form a combustible mixture; combusting the combustible mixture to produce combustion gases for the aspiration; and maintaining the fuel stream substantially free from contact with oxidant prior to the intermixture with aspirated oxidant

  1. [From waste to treasure: turning activated sludge into bioplastic poly-3-hydroxybutyrate].

    Science.gov (United States)

    Chen, Jia'ni

    2017-12-25

    Large quantity of activated sludge is generated from wastewater treatment but without yet an appropriate deposition. High temperature can lyse the activate sludge so that nitrogen and phosphorus containing nutrients are released. Halomonas CJN was found to grow on the heat lysed activated sludge and glucose for production of bioplastic poly-3-hydroxybutyrate (PHB) in the absence of yeast extract, nitrogen and phosphorus sources as well as trace elements. This reduces the PHB production cost significantly. Furthermore, acetic acid formed from anaerobic fermentation of heat lysed activated sludge can be used to replace glucose for cell growth but not much for PHB production. After construction of an additional PHB synthesis pathway in Halomonas CJN, we can produce PHB entirely from heat lysed activated sludge, reducing production cost of PHB roughly from ¥ 30 000 Yuan/ton to ¥ 20 000 Yuan/ton, thus turning waste activated sludge to valuable raw material resource.

  2. Evaluation of the Digestibility of Attached and Suspended Growth Sludge in an Aerobic Digester for a Small Community

    Directory of Open Access Journals (Sweden)

    Shohreh Azizi

    2018-02-01

    Full Text Available The aerobic sludge digestion process for waste sludge generated from suspended biomass (i.e., activated sludge process, ASP and attached biomass (i.e., moving bed bioreactor, MBBR and modified packed bed biofilm, PBBR reactors in a residential complex were analyzed. The rate of digestion with respect to different sludge characteristics generated through these various treatment processes were examined; the results revealed that waste sludge from ASP took 16 days to achieve complete digestion while MBBR and PBBR took nine and seven days, respectively. The most important factors influencing the sludge digestion such as sludge volume index (SVI, mixed liquor suspended solid (MLSS, and mixed liquor volatile suspended solid (MLVSS were examined. The ASP which had the highest initial MLSS and MLVS took a longer time for digestion. Aerobic sludge digestion in all the treatment reactors was studied under laboratory scale conditions in batch experimentation to evaluate sludge characteristics and the rate of digestion as well as through a continuous bench scale pilot system to optimize the process parameters. Removal efficiencies of volatile solids (VS 90.71% in ASP, 84.27% in MBBR and 84.07% in PBBR in aerobic digestion during batch mode were also observed. The study revealed that the aerobic sludge digestion process utilized in curbing sludge is not feasible application for a small community due to very long digestion times and a large amount of space although Packed Bed Biofilm (PBBR used the lowest time (seven days compared to the other systems.

  3. Co-combustion of waste with coal in a circulating fluidised bed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Gulyurtlu, I.; Boavida, D.; Abelha, P.; Lopes, H.; Cabrita, I. [DEECA-INETI, Lisboa (Portugal)

    2002-07-01

    The results of a study of cocombustion of waste with coal is described. Various wastes (biomass, sludge, and refuse derived fuel) were burned with coal in a circulating fluidised bed combustor. Conditions that prevent segregated combustion, reduce production of nitrogen oxides, and attain high combustion efficiency were studied. The effects of variations in air staging in the riser, mixing of air with volatiles, coal/biomass ratio, methods of feeding biomass, and temperature are described. 5 refs., 3 figs., 5 tabs.

  4. Evaluation of the influence of sludge generated coagulant contained in the ETA on ceramic bodies; Avaliacao da influencia do coagulante contido no lodo gerado na ETA em corpos ceramicos

    Energy Technology Data Exchange (ETDEWEB)

    Martins, B.E.D.B.S.; Yokoyama, L.; Almeida, V.C., E-mail: valeria@eq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Centro de Tecnologia. Escola de Quimica

    2014-07-01

    This study aims to evaluate the effects of the insertion of sludge produced in ETA, having both polyaluminum chloride as aluminum sulfate as a coagulant, clay, allowing to obtain an alternative to conventional ceramic material options. Compositions with different percentages of silt by the method of pressing shaping and burned at 900 ° C, 1100 ° C and 1200 ° C were prepared. The specimens were tested for water absorption and flexural stress. Were characterized by the techniques of X-ray fluorescence, X-ray diffraction and scanning electron microscopy results reveal that the nature of the sludge positively affects the quality of the ceramics prepared. (author)

  5. Sewage sludge additive

    Science.gov (United States)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  6. PROCESS DESIGN MANUAL: LAND APPLICATION OF SEWAGE SLUDGE AND DOMESTIC SEPTAGE

    Science.gov (United States)

    Land application of sewage sludge generated by domestic sewage treatment is performed in an environmentally safe and cost–effective manner in many communities. Land application involves taking advantage of the fertilizing and soil conditioning properties of sewage sludge by sp...

  7. Biodegradation of phthalate esters during the mesophilic anaerobic digestion of sludge

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Alatriste-Mondragon, Felipe; Iranpour, R.

    2003-01-01

    Phthalic acid esters (PAE) are commonly found in the sludge generated in the wastewater treatment plants. Anaerobic digestion followed by land application is a common treatment and disposal practice of sludge. To date, many studies exist on the anaerobic biodegradation rates of PAE, especially...

  8. Sewage sludge disposal in Austria

    International Nuclear Information System (INIS)

    Koch, F.

    1997-01-01

    Sewage systems serve about 70% of the Austrian population, producing 6 million m 3 of sewage sludge per year with a dry matter content of 4-5%. At present about 52% of this sludge is disposed of in land fills, 33% is incinerated, and only about 15 % is used in agriculture. Although agricultural utilization is becoming increasingly important, several problems, especially those related to public opinion, need to be resolved before increased use will be possible. In this paper, wastewater treatment and sewage-sludge production in Austria, and problems associated with sludge disposal are discussed. (author)

  9. Composting of sewage sludge irradiated

    International Nuclear Information System (INIS)

    Hashimoto, Shoji; Watanabe, Hiromasa; Nishimura, Koichi; Kawakami, Waichiro

    1981-01-01

    Recently, the development of the techniques to return sewage sludge to forests and farm lands has been actively made, but it is necessary to assure its hygienic condition lest the sludge is contaminated by pathogenic bacteria. The research to treat sewage sludge by irradiation and utilize it as fertilizer or soil-improving material has been carried out from early on in Europe and America. The effects of the irradiation of sludge are sterilization, to kill parasites and their eggs, the inactivation of weed seeds and the improvement of dehydration. In Japan, agriculture is carried out in the vicinity of cities, therefore it is not realistic to use irradiated sludge for farm lands as it is. The composting treatment of sludge by aerobic fermentation is noticed to eliminate the harms when the sludge is returned to forests and farm lands. It is desirable to treat sludge as quickly as possible from the standpoint of sewage treatment, accordingly, the speed of composting is a problem. The isothermal fermentation experiment on irradiated sludge was carried out using a small-scale fermentation tank and strictly controlling fermentation conditions, and the effects of various factors on the fermentation speed were studied. The experimental setup and method are described. The speed of composting reached the maximum at 50 deg C and at neutral or weak alkaline pH. The speed increased with the increase of irradiation dose up to 30 Mrad. (Kako, I.)

  10. Oily Sludge Biodetoxification

    Science.gov (United States)

    2011-05-01

    bio- contactors , 5 membrane reactors, and activated sludge systems have been developed to maximize bacterial contact with the waste and reduce...with a membrane filter that has enabled them to use all of the treated wastewater for plant cooling. xiv 1 1.0 INTRODUCTION 1.1...other activities. To increase the throughput of the filtration unit, the original membranes were replaced with a polysulfone blend spiral wound

  11. The drying of sewage sludge by immersion frying

    Directory of Open Access Journals (Sweden)

    D. P. Silva

    2005-06-01

    Full Text Available The objective of this work was to dry sewage sludge using a fry-drying process. The frying experiments were carried out in commercial fryers modified by adding thermocouples to the setup. During frying, typical drying curves were obtained and it was verified that, in relation to the parameters: oil temperature, oil type and shape of the sample, the shape factor the most effect on the drying rate, at least within the range chosen for the variables studied. Oil uptake and calorific value were also analyzed. The calorific value of the samples increased with frying time, reaching values around 24MJ/kg after 600s of frying (comparable to biocombustibles such as wood and sugarcane bagasse. The process of immersion frying showed great potential for drying materials, especially sewage sludge, obtaining a product with a high energy content, thereby increasing its value as a combustible.

  12. Characteristics of residues from thermally treated anaerobic sludges

    International Nuclear Information System (INIS)

    Friedman, A.A.; Smith, J.E.; De Santis, J.; Ptak, T.; Ganley, R.C.

    1988-01-01

    Sludge management and disposal are probably the most difficult and expensive operations involved in wastewater treatment today. To minimize final disposal costs many waste treatment facilities practice some form of anaerobic digestion and dewatering to reduce the volume and offensiveness of their by-product sludges. One potential alternative for reducing sludge volumes consists of high temperature, partial oxidation of these previously digested sludges (PDS) and subsequent anaerobic biological conversion of resulting soluble organics to methane. This paper describes solids destruction, residue characteristics and biodegradability factors that should be considered in the design of liquid thermal treatment processes for the management of anaerobic sludges. To date only very limited information is available concerning the suitability of thermally treated PDS to serve as a substrate for the generation of methane. The primary objective of this research was to determine the feasibility of producing methane efficiently from the residual VSS in anaerobically digested sludges. Secondary goals were to establish the ''best'' conditions for thermal treatment for solubilizing PDS, to observe the effect of the soluble products on methanogenesis and to evaluate process sidestreams for dewaterability and anaerobic biodegradability

  13. Sludge storage lagoon biogas recovery and use. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Muller, D.; Norville, C. [Memphis and Shelby County Div. of Planning and Development, TN (United States)

    1991-07-01

    The City of Memphis has two wastewater treatment plants. The SWTP employs two large anaerobic digestion sludge lagoons as part of the overall sludge treatment system. Although these lagoons are effective in concentrating and digesting sludge, they can generate offensive odors. The SWTP uses aerobic digesters to partially stabilize the sludge and help reduce objectionable odors before it enters the lagoons. The anaerobic digestion of sludge in the lagoons results in the dispersion of a large quantity of biogas into the atmosphere. The City realized that if the lagoons could be covered, the odor problem could be resolved, and at the same, time, biogas could be recovered and utilized as a source of energy. In 1987, the City commissioned ADI International to conduct a feasibility study to evaluate alternative methods of covering the lagoons and recovering and utilizing the biogas. The study recommended that the project be developed in two phases: (1) recovery of the biogas and (2) utilization of the biogas. Phase 1 consists of covering the two lagoons with an insulated membrane to control odor and temperature and collect the biogas. Phase 1 was found to be economically feasible and offered a unique opportunity for the City to save substantial operating costs at the treatment facility. The Memphis biogas recovery project is the only application in the world where a membrane cover has been used on a municipal wastewater sludge lagoon. It is also the largest lagoon cover system in the world.

  14. Design and assembly of a catalyst bed gas generator for the catalytic decomposition of high concentration hydrogen peroxide propellants and the catalytic combustion of hydrocarbon/air mixtures

    Science.gov (United States)

    Lohner, Kevin A. (Inventor); Mays, Jeffrey A. (Inventor); Sevener, Kathleen M. (Inventor)

    2004-01-01

    A method for designing and assembling a high performance catalyst bed gas generator for use in decomposing propellants, particularly hydrogen peroxide propellants, for use in target, space, and on-orbit propulsion systems and low-emission terrestrial power and gas generation. The gas generator utilizes a sectioned catalyst bed system, and incorporates a robust, high temperature mixed metal oxide catalyst. The gas generator requires no special preheat apparatus or special sequencing to meet start-up requirements, enabling a fast overall response time. The high performance catalyst bed gas generator system has consistently demonstrated high decomposition efficiency, extremely low decomposition roughness, and long operating life on multiple test articles.

  15. Partial oxidation of sewage sludge briquettes in a updraft fixed bed.

    Science.gov (United States)

    Kim, Minsu; Lee, Yongwoon; Park, Jinje; Ryu, Chankook; Ohm, Tae-In

    2016-03-01

    The fixed bed reaction of sewage sludge briquettes was investigated to evaluate the potential applications to gasification, combustion, or production of biochar as soil ameliorator. The reaction had two distinctive stages: ignition propagation and char oxidation. The ignition front of the sludge briquettes propagated at a lower speed, which significantly increased the stoichiometric ratio of overall combustion reaction and peak temperatures. The ignition front also had irregular shapes due to the channeling effects. During the char oxidation stage, the sludge ash agglomerated because of the slow reaction rate and increased CO2 formation. Because of low energy content in the product gas, the large briquettes were not favorable for syngas production. In addition, the low burning rates and ash agglomeration could cause problems in the operation of a grate-type furnace for combustion. However, the char accumulated above the ignition front had similar properties with that from pyrolysis under inert atmosphere. Therefore, the fixed bed reaction under partial oxidation conditions can be applied to produce biochar as soil ameliorator from the sludge briquettes without external heat supply. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Improved waste-activated sludge dewatering using sludge/oil ...

    African Journals Online (AJOL)

    Ultrasonication had low dewatering and energy efficiency with long irradiation times, indicating that it would be difficult to implement in a field plant. The water content of sludge was reduced to 60% within 120 s using microwaves, but dewatering efficiency depended on the thickness and volume of the sludge. In a pilot-scale ...

  17. Combustion Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — For more than 30 years The Combustion Research Facility (CRF) has served as a national and international leader in combustion science and technology. The need for a...

  18. Vitrification as an alternative to landfilling of tannery sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Celary, Piotr, E-mail: pcelary@is.pcz.czest.pl; Sobik-Szołtysek, Jolanta, E-mail: jszoltysek@is.pcz.czest.pl

    2014-12-15

    Highlights: • The possibility of vitrification of tannery sewage sludge was investigated. • Glass cullet was substituted with different wastes of mineral character. • Component ratio in the processed mixtures was optimized. • Environmental safety of the acquired vitrificates was verified. • An alternative management approach of usually landfilled waste was presented. - Abstract: Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling. The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification. The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives. One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with

  19. Investigating the fate of activated sludge extracellular proteins in sludge digestion using sodium dodecyl sulfate polyacrylamide gel electrophoresis.

    Science.gov (United States)

    Park, Chul; Helm, Richard F; Novak, John T

    2008-12-01

    The fate of activated sludge extracellular proteins in sludge digestion was investigated using three different cation-associated extraction methods and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Extraction methods used were the cation exchange resin (CER) method for extracting calcium (Ca2+) and magnesium (Mg2+), sulfide extraction for removing iron, and base treatment (pH 10.5) for dissolving aluminum. Extracellular polymeric substances extracted were then subjected to SDS-PAGE, and the resultant protein profiles were examined before and after sludge digestion. The SDS-PAGE results showed that three methods led to different SDS-PAGE profiles for both undigested and digested sludges. The results further revealed that CER-extracted proteins remained mainly undegraded in anaerobic digestion, but were degraded in aerobic digestion. While the fate of sulfide- and base-extracted proteins was not clear for aerobic digestion, their changes in anaerobic digestion were elucidated. Most sulfide-extracted proteins were removed by anaerobic digestion, while the increase in protein band intensity and diversity was observed for base-extracted proteins. These results suggest that activated sludge flocs contain different fractions of proteins that are distinguishable by their association with certain cations and that each fraction undergoes different fates in anaerobic and aerobic digestion. The proteins that were resistant to degradation and generated during anaerobic digestion were identified by liquid chromatography tandem mass spectrometry. Protein identification results and their putative roles in activated sludge and anaerobic digestion are discussed in this study.

  20. A comparative analysis of in vitro toxicity of diesel exhaust particles from combustion of 1st- and 2nd-generation biodiesel fuels in relation to their physicochemical properties-the FuelHealth project.

    Science.gov (United States)

    Lankoff, Anna; Brzoska, Kamil; Czarnocka, Joanna; Kowalska, Magdalena; Lisowska, Halina; Mruk, Remigiusz; Øvrevik, Johan; Wegierek-Ciuk, Aneta; Zuberek, Mariusz; Kruszewski, Marcin

    2017-08-01

    Biodiesels represent more carbon-neutral fuels and are introduced at an increasing extent to reduce emission of greenhouse gases. However, the potential impact of different types and blend concentrations of biodiesel on the toxicity of diesel engine emissions are still relatively scarce and to some extent contradictory. The objective of the present work was to compare the toxicity of diesel exhaust particles (DEP) from combustion of two 1st-generation fuels: 7% fatty acid methyl esters (FAME; B7) and 20% FAME (B20) and a 2nd-generation 20% FAME/HVO (synthetic hydrocarbon biofuel (SHB)) fuel. Our findings indicate that particulate emissions of each type of biodiesel fuel induce cytotoxic effects in BEAS-2B and A549 cells, manifested as cell death (apoptosis or necrosis), decreased protein concentrations, intracellular ROS production, as well as increased expression of antioxidant genes and genes coding for DNA damage-response proteins. The different biodiesel blend percentages and biodiesel feedstocks led to marked differences in chemical composition of the emitted DEP. The different DEPs also displayed statistically significant differences in cytotoxicity in A549 and BEAS-2B cells, but the magnitude of these variations was limited. Overall, it seems that increasing biodiesel blend concentrations from the current 7 to 20% FAME, or substituting 1st-generation FAME biodiesel with 2nd-generation HVO biodiesel (at least below 20% blends), affects the in vitro toxicity of the emitted DEP to some extent, but the biological significance of this may be moderate.

  1. Bioprocessing of sewage sludge for safe recycling on agricultural land - BIOWASTE

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Jens Ejbye; Angelidaki, Irini; Christensen, Nina; Batstone, Damien John; Lyberatos, Gerasimos; Stamatelatou, Katerina; Lichtfouse, Eric; Elbisser, Brigitte; Rogers, Kayne; Sappin-Didier, Valerie; Dernaix, Laurence; Caria; Giovanni; Metzger, Laure; Borghi, Veronica; Montcada, Eloi

    2003-07-01

    Disposal and handling of sewage sludge are increasing problems in Europe due to the increasing quantities of the sewage sludge produced. A large amount of the sewage sludge contains small fractions of toxic chemicals, which results in problems with safe use of the sewage sludge on agricultural land. From an ecological and economical point of view, it would be essential to establish methodologies, which could allow sewage sludge to be reused as fertilizers on agricultural land. Energy efficient biotreatment processes of organic waste are, therefore, of crucial importance. BIOWASTE will offer an integrated study of this area. The typical composition of sewage sludge will be characterized with regard to key contaminating compounds. The following compounds will be in focus: Emulsifying agents such as nonylphenols and nonylphenol ethoxylates (NPE), polycyclic aromatic hydrocarbons (PAHs) derived from incomplete combustion processes and phthalates, which are used as additives in plastics and surfactants such as linear alkyl benzene sulfonate (LAS). Analytical techniques suitable for qualitative and quantitative evaluation of the chemical species involved in the processes under investigation will be determined. Bacteria that are able to degrade selected contaminating compounds under anaerobic and aerobic conditions will be isolated, characterized and bioaugmented for decontamination of sewage sludge through bioprocessing. Aerobic, anaerobic and combination of aerobic/anaerobic bioprocessing of sewage sludge will be applied. A mathematical model will be developed to describe the biodegradation processes of the contaminating compounds after establishing the kinetic parameters for degradation of contaminating compounds. The bioprocessed sewage sludge will be used in eco- and plant- toxicology tests to evaluate the impact of the xenobiotics on the environment. Methodologies will be developed and applied to assess the cleanliness of the bioprocessing as a safe method for waste

  2. Sludge Treatment Project Engineered Container Retrieval And Transfer System Prelminary Design Hazard And Operability Study

    International Nuclear Information System (INIS)

    Carro, C.A.

    2011-01-01

    This Hazard and Operability (HAZOP) study addresses the Sludge Treatment Project (STP) Engineered Container Retrieval and Transfer System (ECRTS) preliminary design for retrieving sludge from underwater engineered containers located in the 105-K West (KW) Basin, transferring the sludge as a sludge-water slurry (hereafter referred to as 'slurry') to a Sludge Transport and Storage Container (STSC) located in a Modified KW Basin Annex, and preparing the STSC for transport to T Plant using the Sludge Transport System (STS). There are six, underwater engineered containers located in the KW Basin that, at the time of sludge retrieval, will contain an estimated volume of 5.2 m 3 of KW Basin floor and pit sludge, 18.4 m 3 of 105-K East (KE) Basin floor, pit, and canister sludge, and 3.5 m 3 of settler tank sludge. The KE and KW Basin sludge consists of fuel corrosion products (including metallic uranium, and fission and activation products), small fuel fragments, iron and aluminum oxide, sand, dirt, operational debris, and biological debris. The settler tank sludge consists of sludge generated by the washing of KE and KW Basin fuel in the Primary Clean Machine. A detailed description of the origin of sludge and its chemical and physical characteristics can be found in HNF-41051, Preliminary STP Container and Settler Sludge Process System Description and Material Balance. In summary, the ECRTS retrieves sludge from the engineered containers and hydraulically transfers it as a slurry into an STSC positioned within a trailer-mounted STS cask located in a Modified KW Basin Annex. The slurry is allowed to settle within the STSC to concentrate the solids and clarify the supernate. After a prescribed settling period the supernate is decanted. The decanted supernate is filtered through a sand filter and returned to the basin. Subsequent batches of slurry are added to the STSC, settled, and excess supernate removed until the prescribed quantity of sludge is collected. The sand

  3. SLUDGE TREATMENT PROJECT ENGINEERED CONTAINER RETRIEVAL AND TRANSFER SYSTEM PRELMINARY DESIGN HAZARD AND OPERABILITY STUDY

    Energy Technology Data Exchange (ETDEWEB)

    CARRO CA

    2011-07-15

    This Hazard and Operability (HAZOP) study addresses the Sludge Treatment Project (STP) Engineered Container Retrieval and Transfer System (ECRTS) preliminary design for retrieving sludge from underwater engineered containers located in the 105-K West (KW) Basin, transferring the sludge as a sludge-water slurry (hereafter referred to as 'slurry') to a Sludge Transport and Storage Container (STSC) located in a Modified KW Basin Annex, and preparing the STSC for transport to T Plant using the Sludge Transport System (STS). There are six, underwater engineered containers located in the KW Basin that, at the time of sludge retrieval, will contain an estimated volume of 5.2 m{sup 3} of KW Basin floor and pit sludge, 18.4 m{sup 3} of 105-K East (KE) Basin floor, pit, and canister sludge, and 3.5 m{sup 3} of settler tank sludge. The KE and KW Basin sludge consists of fuel corrosion products (including metallic uranium, and fission and activation products), small fuel fragments, iron and aluminum oxide, sand, dirt, operational debris, and biological debris. The settler tank sludge consists of sludge generated by the washing of KE and KW Basin fuel in the Primary Clean Machine. A detailed description of the origin of sludge and its chemical and physical characteristics can be found in HNF-41051, Preliminary STP Container and Settler Sludge Process System Description and Material Balance. In summary, the ECRTS retrieves sludge from the engineered containers and hydraulically transfers it as a slurry into an STSC positioned within a trailer-mounted STS cask located in a Modified KW Basin Annex. The slurry is allowed to settle within the STSC to concentrate the solids and clarify the supernate. After a prescribed settling period the supernate is decanted. The decanted supernate is filtered through a sand filter and returned to the basin. Subsequent batches of slurry are added to the STSC, settled, and excess supernate removed until the prescribed quantity of sludge is

  4. Utilization of coal mine ventilation exhaust as combustion air in gas-fired turbines for electric and/or mechanical power generation. Semi-annual topical report, June 1995--August 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-01

    Methane emitted during underground coal mining operations is a hazard that is dealt with by diluting the methane with fresh air and exhausting the contaminated air to the atmosphere. Unfortunately this waste stream may contain more than 60% of the methane resource from the coal, and in the atmosphere the methane acts as a greenhouse gas with an effect about 24.5 times greater than CO{sub 2}. Though the waste stream is too dilute for normal recovery processes, it can be used as combustion air for a turbine-generator, thereby reducing the turbine fuel requirements while reducing emissions. Preliminary analysis indicates that such a system, built using standard equipment, is economically and environmentally attractive, and has potential for worldwide application.

  5. Re-use of drinking water treatment plant (DWTP) sludge: Characterization and technological behaviour of cement mortars with atomized sludge additions

    International Nuclear Information System (INIS)

    Husillos Rodriguez, N.; Martinez Ramirez, S.; Blanco Varela, M.T.; Guillem, M.; Puig, J.; Larrotcha, E.; Flores, J.

    2010-01-01

    This paper aims to characterize spray-dried DWTP sludge and evaluate its possible use as an addition for the cement industry. It describes the physical, chemical and micro-structural characterization of the sludge as well as the effect of its addition to Portland cements on the hydration, water demand, setting and mechanical strength of standardized mortars. Spray drying DWTP sludge generates a readily handled powdery material whose particle size is similar to those of Portland cement. The atomized sludge contains 12-14% organic matter (mainly fatty acids), while its main mineral constituents are muscovite, quartz, calcite, dolomite and seraphinite (or clinoclor). Its amorphous material content is 35%. The mortars were made with type CEM I Portland cement mixed with 10 to 30% atomized sludge exhibited lower mechanical strength than the control cement and a decline in slump. Setting was also altered in the blended cements with respect to the control.

  6. Production of oil and coke from sludges containing organic pollutants; Gewinnung von Oel und Koks aus organisch belasteten Schlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Steger, M. [Martin Steger GmbH, Eggenfelden (Germany); Meissner, W.; Herold, R. [Max Aicher Umwelttechnik GmbH, Freilassing (Germany)

    1998-09-01

    Since the mid-eighties, Messrs. Max Aicher Umwelttechnik GmbH at Hammerau, Germany have been investigating sewage sludge pyrolysis. Laboratory experiments and semi-industrial investigations led to the construction of a combined sludge drying and conversion plant (``Aicher sludge recycling process``), in which the organic sludge fraction is converted into recyclable or combustible oils. Carbon is obtained as a by-product in solid form as conversion coke which can be utilized. Apart from sewage sludge, also industrial sludges with high organic fractions can be processed, e.g. sludges and sewage sludges from petroleum processing. (orig.) [Deutsch] In der Bundesrepublik Deutschland beschaeftigt sich die Max Aicher Umwelttechnik GmbH in Hammerau seit Mitte der Achtzigerjahre mit der Niedertemperaturkonvertierung (Pyrolyse) von Klaerschlamm. Versuche im Labor- und im halbtechnischen Massstab fuehrten zur Realisierung einer betriebstechnischen Anlage mit den Komponenten Schlammtrocknung und Konvertierung. Ziel des Aicher-Schlamm-Recycling-Verfahrens ist die Umwandlung der organischen Schlammfraktion in stofflich und energetisch verwertbare Oele. Bei der Umwandlung entsteht fixer Kohlenstoff, der im festen Rueckstand (Konversionskoks) angereichert wird. Neben dem gewonnenen Oel ist auch der produzierte Koks verwertbar. Einsatzstoffe fuer das Verfahren sind neben Klaerschlamm aus der kommunalen Abwasserreinigung vor allem industrielle Schlaemme mit hohen organischen Anteilen z.B. Schlaemme und Klaerschlaemme aus der Erdoelverarbeitung. (orig.)

  7. Sludge Digestion Manual; Handboek Slibgisting

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-15

    This manual offers a guideline for developing, designing, optimizing and operating sludge digestion installations based on sewage sludge. It also offers tools for solving operation problems [Dutch] Het Handboek is een leidraad voor het ontwikkelen, ontwerpen, optimaliseren en bedrijven van slibgistingsinstallaties voor zuiveringsslib. Ook geeft het handvatten voor het oplossen van operationele problemen.

  8. Constraints to increased sludge utilization

    International Nuclear Information System (INIS)

    Pound, C.E.; Bory, L.D.

    1979-01-01

    The management and disposition of municipal sewage sludge is a growing problem as secondary treatment plants are completed to meet Clean Water Act standards. The prohibition of ocean dumping, the increased cost and difficulty to secure and operate sludge landfills, and the high energy costs of dewatering and incineration should all contribute to an increase in land application. However, land application and other beneficial use alternatives, such as give away/sale, account for only 20% of the 12 m/day tons of sludge produced nationally. This result can in part be attributed to public health, institutional, and legal constraints on implementing land application systems. Public health constraints include contaminants in sludge which may pose a risk to human health. Much current controversy about the safety of applying sludge to agricultural land on which food chain crops are grown focuses on heavy metals, especially cadmium. But proposed federal and state regulation of cadmium concentrations in sludge, at levels where human health risk has not been demonstrated, may limit utilization by land application. State operating rules and other administrative controls over sludge application are among the institutional constraints. Since land is an essential element in a land application system, securing adequate and suitable land involves legal constraints. Involuntary acquisition and zoning procedures can delay and frustrate land application programs. Securing indemnity insurance for possible damage to land to which sludge is applied has also been an obstacle to implementation of utilization programs

  9. ASSESSING SPECIATION AND RELEASE OF HEAVY METALS FROM COAL COMBUSTION PRODUCTS

    Science.gov (United States)

    In this study, the speciation of heavy metals such as arsenic, selenium, lead, zinc and mercury in coal combustion products (CCPs) was evaluated using sequential extraction procedures. Coal fly ash, bottom ash and flue gas desulphurization (FGD) sludge samples were used in the ex...

  10. PROGRESS WITH K BASINS SLUDGE RETRIEVAL STABILIZATION & PACKAGING AT THE HANFORD NUCLEAR SITE

    Energy Technology Data Exchange (ETDEWEB)

    KNOLLMEYER, P.M.; PHILLIPS, C; TOWNSON, P.S.

    2006-01-30

    This paper shows how Fluor Hanford and BNG America have combined nuclear plant skills from the U.S. and the U.K. to devise methods to retrieve and treat the sludge that has accumulated in K Basins at the Hanford Site over many years. Retrieving the sludge is the final stage in removing fuel and sludge from the basins to allow them to be decontaminated and decommissioned, so as to remove the threat of contamination of the Columbia River. A description is given of sludge retrieval using vacuum lances and specially developed nozzles and pumps into Consolidation Containers within the basins. The special attention that had to be paid to the heat generation and potential criticality issues with the irradiated uranium-containing sludge is described. The processes developed to re-mobilize the sludge from the Consolidation Containers and pump it through flexible and transportable hose-in-hose piping to the treatment facility are explained with particular note made of dealing with the abrasive nature of the sludge. The treatment facility, housed in an existing Hanford building, is described, and the uranium-corrosion and grout packaging processes explained. The uranium corrosion process is a robust, tempered process very suitable for dealing with a range of differing sludge compositions. Optimization and simplification of the original sludge corrosion process design is described and the use of transportable and reusable equipment is indicated. The processes and techniques described in the paper are shown to have wide applicability to nuclear cleanup.

  11. A novel method for harmless disposal and resource reutilization of steel wire rope sludges.

    Science.gov (United States)

    Zhang, Li; Liu, Yang-Sheng

    2016-10-01

    Rapid development of steel wire rope industry has led to the generation of large quantities of pickling sludge, which causes significant ecological problems and considerable negative environmental effects. In this study, a novel method was proposed for harmless disposal and resource reutilization of the steel wire rope sludge. Based on the method, two steel wire rope sludges (the Pb sludge and the Zn sludge) were firstly extracted by hydrochloric or sulfuric acid and then mixed with the hydrochloride acid extracting solution of aluminum skimmings to produce composite polyaluminum ferric flocculants. The optimum conditions (acid concentration, w/v ratio, reaction time, and reaction temperature) for acid extraction of the sludges were studied. Results showed that 97.03 % of Pb sludge and 96.20 % of Zn sludge were extracted. Leaching potential of the residues after acid extraction was evaluated, and a proposed treatment for the residues had been instructed. The obtained flocculant products were used to purify the real domestic wastewater and showed an equivalent or better performance than the commercial ones. This method is environmental-friendly and cost-effective when compared with the conventional sludge treatments.

  12. Beneficial reuse of precast concrete industry sludge to produce alkaline stabilized biosolids.

    Science.gov (United States)

    Gowda, C; Seth, R; Biswas, N

    2008-01-01

    The precast concrete industry generates waste called concrete sludge during routine mixer tank washing. It is highly alkaline and hazardous, and typically disposed of by landfilling. This study examined the stabilization of municipal sewage sludge using concrete sludge as an alkaline agent. Sewage sludge was amended with 10 to 40% of concrete sludge by wet weight, and 10 and 20% of lime by dry weight of the sludge mix. Mixes containing 30 and 40% of concrete sludge with 20% lime fulfilled the primary requirements of Category 1 and 2 (Canada) biosolids of maintaining a pH of 12 for at least 72 hours. The heavy metals were below Category 1 regulatory limits. The 40% concrete sludge mix was incubated at 52 degrees C for 12 of the 72 hours to achieve the Category 1 and 2 regulations of less than 1000 fecal coliform/g solids. The nutrient content of the biosolids was 8.2, 10 and 0.6 g/kg of nitrogen, phosphorus and potassium respectively. It can be used as a top soil or augmented with potassium for use as fertilizer. The study demonstrates that concrete sludge waste can be beneficially reused to produce biosolids, providing a long-term sustainable waste management solution for the concrete industry.

  13. Uncertainties in hydrogen combustion

    International Nuclear Information System (INIS)

    Stamps, D.W.; Wong, C.C.; Nelson, L.S.

    1988-01-01

    Three important areas of hydrogen combustion with uncertainties are identified: high-temperature combustion, flame acceleration and deflagration-to-detonation transition, and aerosol resuspension during hydrogen combustion. The uncertainties associated with high-temperature combustion may affect at least three different accident scenarios: the in-cavity oxidation of combustible gases produced by core-concrete interactions, the direct containment heating hydrogen problem, and the possibility of local detonations. How these uncertainties may affect the sequence of various accident scenarios is discussed and recommendations are made to reduce these uncertainties. 40 references

  14. Modeling of combustion noise in helicopter engines

    OpenAIRE

    Livebardon, Thomas

    2015-01-01

    The growth of air traffic at the vicinity of areas at high population density imposes to make quieter aircrafts on aeronautical manufacturers.The engine noise is one of the major contributors to the overall sound levels. Furthermore, the combustion is known to be responsible for a broadband noise generation at low-frequency. The combustion noise can be put into two main mechanisms. The first one is the emission of sound pulses by the unsteady heat release of the combustion process and is call...

  15. Optimization of co-digestion of various industrial sludges for biogas production and sludge treatment: methane production potential experiments and modeling.

    Science.gov (United States)

    Mahanty, Biswanath; Zafar, Mohd; Han, Man Jae; Park, Hung-Suck

    2014-06-01

    Optimal biogas production and sludge treatment were studied by co-digestion experiments and modeling using five different wastewater sludges generated from paper, chemical, petrochemical, automobile, and food processing industries situated in Ulsan Industrial Complex, Ulsan, South Korea. The biomethane production potential test was conducted in simplex-centroid mixture design, fitted to regression equation, and some optimal co-digestion scenarios were given by combined desirability function based multi-objective optimization technique for both methane yield and the quantity of sludge digested. The co-digestion model incorporating main and interaction effects among sludges were utilized to predict the maximum possible methane yield. The optimization routine for methane production with different industrial sludges in batches were repeated with the left-over sludge of earlier cycle, till all sludges have been completely treated. Among the possible scenarios, a maximum methane yield of 1161.53 m(3) is anticipated in three batches followed by 1130.33 m(3) and 1045.65 m(3) in five and two batches, respectively. This study shows a scientific approach to find a practical solution to utilize diverse industrial sludges in both treatment and biogas production perspectives. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. K Basin Sludge Conditioning Testing. Nitric Acid Dissolution Testing of K East Area Sludge Composite, Small- and Large-Scale Testing

    International Nuclear Information System (INIS)

    Carlson, C.D.; Delegard, C.H.; Burgeson, I.E.; Schmidt, A.J.; Silvers, K.L.

    1998-01-01

    This report describes work performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) to support the development of the K Basin Sludge Treatment System. For this work, testing was performed to examine the dissolution behavior of a K East Basin floor and Weasel Pit sludge composite, referred to as K East area sludge composite, in nitric acid at the following concentrations: 2 M, 4 M, 6 M and 7.8 M. With the exception of one high solids loading test the nitric acid was added at 4X the stoichiometric requirement (assuming 100% of the sludge was uranium metal). The dissolution tests were conducted at boiling temperatures for 24 hours. Most of the tests were conducted with approximately2.5 g of sludge (dry basis). The high solids loading test was conducted with approximately7 g of sludge. A large-scale dissolution test was conducted with 26.5 g of sludge and 620 mL of 6 M nitric acid. The objectives of this test were to (1) generate a sufficient quantity of acid-insoluble residual solids for use in leaching studies, and (2) examine the dissolution behavior of the sludge composite at a larger scale

  17. Lipid profiling in sewage sludge.

    Science.gov (United States)

    Zhu, Fenfen; Wu, Xuemin; Zhao, Luyao; Liu, Xiaohui; Qi, Juanjuan; Wang, Xueying; Wang, Jiawei

    2017-06-01

    High value-added reutilization of sewage sludge from wastewater treatment plants (WWTPs) is essential in sustainable development in WWTPs. However, despite the advantage of high value reutilization, this process must be based on a detailed study of organics in sludge. We used the methods employed in life sciences to determine the profile of lipids (cellular lipids, free fatty acids (FFAs), and wax/gum) in five sludge samples obtained from three typical WWTPs in Beijing; these samples include one sludge sample from a primary sedimentation tank, two activated sludge samples from two Anaerobic-Anoxic-Oxic (A2/O) tanks, and two activated sludge samples from two membrane bioreactor tanks. The percentage of total raw lipids varied from 2.90% to 12.3%. Sludge from the primary sedimentation tank showed the highest concentrations of lipid, FFA, and wax/gum and the second highest concentration of cellular lipids. All activated sludge contained an abundance of cellular lipids (>54%). Cells in sludge can from plants, animals, microbes and so on in wastewater. Approximately 14 species of cellular lipids were identified, including considerable high value-potential ceramide (9567-38774 mg/kg), coenzyme (937-3897 mg/kg), and some phosphatidylcholine (75-548 mg/kg). The presence of those lipid constituents would thus require a wider range of recovery methods for sludge. Both cellular lipids and FFAs contain an abundance of C16-C18 lipids at high saturation level, and they serve as good resources for biodiesel production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Ultrasonic sludge pretreatment under pressure.

    Science.gov (United States)

    Le, Ngoc Tuan; Julcour-Lebigue, Carine; Delmas, Henri

    2013-09-01

    The objective of this work was to optimize the ultrasound (US) pretreatment of sludge. Three types of sewage sludge were examined: mixed, secondary and secondary after partial methanisation ("digested" sludge). Thereby, several main process parameters were varied separately or simultaneously: stirrer speed, total solid content of sludge (TS), thermal operating conditions (adiabatic vs. isothermal), ultrasonic power input (PUS), specific energy input (ES), and for the first time external pressure. This parametric study was mainly performed for the mixed sludge. Five different TS concentrations of sludge (12-36 g/L) were tested for different values of ES (7000-75,000 kJ/kgTS) and 28 g/L was found as the optimum value according to the solubilized chemical oxygen demand in the liquid phase (SCOD). PUS of 75-150 W was investigated under controlled temperature and the "high power input - short duration" procedure was the most effective at a given ES. The temperature increase in adiabatic US application significantly improved SCOD compared to isothermal conditions. With PUS of 150 W, the effect of external pressure was investigated in the range of 1-16 bar under isothermal and adiabatic conditions for two types of sludge: an optimum pressure of about 2 bar was found regardless of temperature conditions and ES values. Under isothermal conditions, the resulting improvement of sludge disintegration efficacy as compared to atmospheric pressure was by 22-67% and 26-37% for mixed and secondary sludge, respectively. Besides, mean particle diameter (D[4,3]) of the three sludge types decreased respectively from 408, 117, and 110 μm to about 94-97, 37-42, and 36-40 μm regardless of sonication conditions, and the size reduction process was much faster than COD extraction. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Treatment of radioactive sludge

    International Nuclear Information System (INIS)

    Allison, W.; Payne, B.J.; Pegler, G.E.

    1979-01-01

    Radioactive sludge e.g. that which may accumulate in irradiated nuclear fuel element storage ponds, is treated by pumping it from a settling tank to a particle separator, conveniently a hydrocyclone and a sloping plate separator, the liquid being returned to the settling tank and the solids being metered into a drum pre-lined with dry cement. The drums are in a containment box in which they are transferred to a mixing station where the particles and cement are mixed and thence to a curing station. After curing the drums are embedded in cement in outer containers for transport to a long-term storage site. (author)

  20. Fluidized bed combustion of low-grade coal and wastes: Research and development

    Energy Technology Data Exchange (ETDEWEB)

    Borodulya, V.A.; Dikalenko, V.I.; Palchonok, G.I.; Vinogradov, L.M. [Academy of Sciences of Belarus, Minsk (Belarus). A.V. Luikov Heat and Mass Transfer Inst.; Dobkin, S.M.; Telegin, E.M. [Special Design Office, Brest (Belarus)

    1994-12-31

    Experimental studies were carried out to investigate devolatilization of fuel as single spherical particles of wood, hydrolytic lignin, leather sewage sludge and Belarussian brown coals in a fluidized bed of sand. It is found that the devolatilization process depends on moisture and ash contents in fuel and on the external heat and mass transfer rate. The char combustion occurs largely in the intermediate region. Kinetic parameters of the devolatilization and char combustion are obtained. A low-capacity fluidized bed boiler suitable for combustion of coal and different wastes is described.

  1. Signal Processing Methods for Liquid Rocket Engine Combustion Spontaneous Stability and Rough Combustion Assessments

    Science.gov (United States)

    Kenny, R. Jeremy; Casiano, Matthew; Fischbach, Sean; Hulka, James R.

    2012-01-01

    Liquid rocket engine combustion stability assessments are traditionally broken into three categories: dynamic stability, spontaneous stability, and rough combustion. This work focuses on comparing the spontaneous stability and rough combustion assessments for several liquid engine programs. The techniques used are those developed at Marshall Space Flight Center (MSFC) for the J-2X Workhorse Gas Generator program. Stability assessment data from the Integrated Powerhead Demonstrator (IPD), FASTRAC, and Common Extensible Cryogenic Engine (CECE) programs are compared against previously processed J-2X Gas Generator data. Prior metrics for spontaneous stability assessments are updated based on the compilation of all data sets.

  2. New class of combustion processes

    International Nuclear Information System (INIS)

    Merzhanov, A.G.; Borovinskaya, I.P.

    1975-01-01

    A short review is given of the results of work carried out since 1967 on studying the combustion processes caused by the interaction of chemical elements in the condensed phase and leading to the formation of refractory compounds. New phenomena and processes are described which are revealed when investigating the combustion of the systems of this class, viz solid-phase combustion, fast combustion in the condensed phase, filtering combustion, combustion in liquid nitrogen, spinning combustion, self-oscillating combustion, and repeated combustion. A new direction in employment of combustion processes is discussed, viz. a self-propagating high-temperature synthesis of refractory nitrides, carbides, borides, silicides and other compounds

  3. Combustion-Generated Nanoparticulates in the El Paso, TX, USA / Juarez, Mexico Metroplex: Their Comparative Characterization and Potential for Adverse Health Effects

    Directory of Open Access Journals (Sweden)

    J. Venzor, III

    2006-03-01

    Full Text Available In this paper we report on the collection of fine (PM1 and ultrafine (PM0.1, or nanoparticulate, carbonaceous materials using thermophoretic precipitation onto silicon monoxide/formvar-coated 3 mm grids which were examined in the transmission electron microscope (TEM. We characterize and compare diesel particulate matter (DPM, tire particulate matter (TPM, wood burning particulate matter, and other soot (or black carbons (BC along with carbon nanotube and related fullerene nanoparticle aggregates in the outdoor air, as well as carbon nanotube aggregates in the indoor air; and with reference to specific gas combustion sources. These TEM investigations include detailed microstructural and microdiffraction observations and comparisons as they relate to the aggregate morphologies as well as their component (primary nanoparticles. We have also conducted both clinical surveys regarding asthma incidence and the use of gas cooking stoves as well as random surveys by zip code throughout the city of El Paso. In addition, we report on short term (2 day and longer term (2 week in vitro assays for black carbon and a commercial multiwall carbon nanotube aggregate sample using a murine macrophage cell line, which demonstrate significant cytotoxicity; comparable to a chrysotile asbestos nanoparticulate reference. The multi-wall carbon nanotube aggregate material is identical to those collected in the indoor and outdoor air, and may serve as a surrogate. Taken together with the plethora of toxic responses reported for DPM, these findings prompt concerns for airborne carbonaceous nanoparticulates in general. The implications of these preliminary findings and their potential health effects, as well as directions for related studies addressing these complex issues, will also be examined.

  4. Ash quality and environmental quality assurance system in co-combustion - Co-combustion of forest industry waste

    International Nuclear Information System (INIS)

    Laine-Ylijoki, J.; Wahlstroem, M.

    2000-01-01

    The environmental acceptability and possible utilization of co-combustion ashes will have a significant influence on the wider use of co-combustion in the future. At present the correlation between currently used fuels, their mixture ratios, and quality variations in ashes are not known, which complicates the assessment of possible utilization and environmental acceptability of co-combustion ashes. The composition of ashes has also been found to vary significantly. Effective utilization requires that process variations to alter ash composition and quality variations are known in advance. The aim of the research was to characterize the fly ash from co- combustion of peat, wood and biological paper mill sludge produced under different fuel loadings, especially with and without sludge addition, ant to identify critical parameters influencing on the ash composition. The variations in the leaching properties of ashes collected daily were followed up. The environmental acceptability of the ashes produced under different fuel loadings, especially their suitability for use in road constructions, were evaluated. The project included also the preparation of laboratory reference material from ash material. Guidelines were developed for sampling, sample preparation and analysis, and leaching tests. Furthermore, a quality control system, including sampling strategies, sample analysis and leaching testing, was established

  5. Effects of sulfur on lead partitioning during sludge incineration based on experiments and thermodynamic calculations.

    Science.gov (United States)

    Liu, Jing-yong; Huang, Shu-jie; Sun, Shui-yu; Ning, Xun-an; He, Rui-zhe; Li, Xiao-ming; Chen, Tao; Luo, Guang-qian; Xie, Wu-ming; Wang, Yu-Jie; Zhuo, Zhong-xu; Fu, Jie-wen

    2015-04-01

    Experiments in a tubular furnace reactor and thermodynamic equilibrium calculations were conducted to investigate the impact of sulfur compounds on the migration of lead (Pb) during sludge incineration. Representative samples of typical sludge with and without the addition of sulfur compounds were combusted at 850 °C, and the partitioning of Pb in the solid phase (bottom ash) and gas phase (fly ash and flue gas) was quantified. The results indicate that three types of sulfur compounds (S, Na2S and Na2SO4) added to the sludge could facilitate the volatilization of Pb in the gas phase (fly ash and flue gas) into metal sulfates displacing its sulfides and some of its oxides. The effect of promoting Pb volatilization by adding Na2SO4 and Na2S was superior to that of the addition of S. In bottom ash, different metallic sulfides were found in the forms of lead sulfide, aluminosilicate minerals, and polymetallic-sulfides, which were minimally volatilized. The chemical equilibrium calculations indicated that sulfur stabilizes Pb in the form of PbSO4(s) at low temperatures (sludge incineration process mainly depended on the gas phase reaction, the surface reaction, the volatilization of products, and the concentration of Si, Ca and Al-containing compounds in the sludge. These findings provide useful information for understanding the partitioning behavior of Pb, facilitating the development of strategies to control the volatilization of Pb during sludge incineration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Internal and surface phenomena in metal combustion

    Science.gov (United States)

    Dreizin, Edward L.; Molodetsky, Irina E.; Law, Chung K.

    1995-01-01

    Combustion of metals has been widely studied in the past, primarily because of their high oxidation enthalpies. A general understanding of metal combustion has been developed based on the recognition of the existence of both vapor-phase and surface reactions and involvement of the reaction products in the ensuing heterogeneous combustion. However, distinct features often observed in metal particle combustion, such as brightness oscillations and jumps (spearpoints), disruptive burning, and non-symmetric flames are not currently understood. Recent metal combustion experiments using uniform high-temperature metal droplets produced by a novel micro-arc technique have indicated that oxygen dissolves in the interior of burning particles of certain metals and that the subsequent transformations of the metal-oxygen solutions into stoichiometric oxides are accompanied with sufficient heat release to cause observed brightness and temperature jumps. Similar oxygen dissolution has been observed in recent experiments on bulk iron combustion but has not been associated with such dramatic effects. This research addresses heterogeneous metal droplet combustion, specifically focusing on oxygen penetration into the burning metal droplets, and its influence on the metal combustion rate, temperature history, and disruptive burning. A unique feature of the experimental approach is the combination of the microgravity environment with a novel micro-arc Generator of Monodispersed Metal Droplets (GEMMED), ensuring repeatable formation and ignition of uniform metal droplets with controllable initial temperature and velocity. The droplet initial temperatures can be adjusted within a wide range from just above the metal melting point, which provides means to ignite droplets instantly upon entering an oxygen containing environment. Initial droplet velocity will be set equal to zero allowing one to organize metal combustion microgravity experiments in a fashion similar to usual microgravity

  7. Sewage sludge as a biomass energy source

    OpenAIRE

    Pavel Kolat; Zdeněk Kadlec

    2013-01-01

    The major part of the dry matter content of sewage sludge consists of nontoxic organic compounds, in general a combination of primary sludge and secondary microbiological sludge. The sludge also contains a substantive amount of inorganic material and a small amount of toxic components. There are many sludge-management options in which production of energy is one of the key treatment steps. The most important options are anaerobic digestion, co-digestion, incineration in combination with energ...

  8. Combustion modeling in internal combustion engines

    Science.gov (United States)

    Zeleznik, F. J.

    1976-01-01

    The fundamental assumptions of the Blizard and Keck combustion model for internal combustion engines are examined and a generalization of that model is derived. The most significant feature of the model is that it permits the occurrence of unburned hydrocarbons in the thermodynamic-kinetic modeling of exhaust gases. The general formulas are evaluated in two specific cases that are likely to be significant in the applications of the model.

  9. Technical notes for the conceptual design for an atmospheric fluidized-bed direct combustion power generating plant. [Comparison of AFB plant and pulverized coal plant

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-04-01

    The first part of this report presents a comparison of the conceptual designs of a large (570 MW(e)) pulverized coal (PC) steam generator equipped with a wet limestone flue gas desulfurization (FGD) system and two equivalent sized atmospheric fluidized bed (AFB) steam generators including balance of plants for electric-power generation. The reader is cautioned that this portion of the report compares a zero generation AFB technology to pulverized coal technology which has been operationally and economically optimized for the past half-century. This comparison is intended to be indicative of whether further development of the AFB concept as a viable alternative to the PC/FGD concept for electric-power generation is merited. In the second part, the load-following capability of a once-through subcritical atmospheric fluidized bed boiler is analyzed. Digital computer simulation predictions of the plant's response to open loop step changes in firing rate, feedwater flow, governor valve, unit load demand, etc, are made. The predicted response of throttle pressure, steam temperature, unit load, etc, are compared to the response of a conventional coal-fired, once-through, subcritical unit. The load-following capability is assessed through this qualitative comparison. Additional model response predictions are also presented for which no test data are presently available.

  10. Influence of anaerobic co-digestion of sewage and brewery sludges on biogas production and sludge quality.

    Science.gov (United States)

    Pecharaply, Athapol; Parkpian, Preeda; Annachhatre, Ajit P; Jugsujinda, Aroon

    2007-06-01

    potassium (K) 0.95-0.96%. The heavy metals, chromium (Cr) and copper (Cu) remaining in digested sludge were present at relatively high levels (Cr 1,849-4,230 and Cu 930-2,526 mg/kg dried sludge). The metals were present as organic matter-bound and sulfide-bound fractions that are not soluble and available. The digested sludge could be safely applied to soil as a plant nutrient source, without fecal coliforms or heavy metals risk. A sludge mixture ratio of 25:75 (sewage:brewery), which generated the higher nutrient concentrations (N=4.22%, P=3.20% and K=0.95%), biogas production and treatment efficiency meet the Bangkok Metropolitan Administration (BMA) safety guidelines required for agricultural application. Biogas production and methane at the 25:75 ratio (sewage:brewery) yielded highest amount of VSremoved (0.65 m3/kg) and CODremoved (220 L/kg), respectively.

  11. Verification of Conditions for use of Combustion Products‘ Heat

    Directory of Open Access Journals (Sweden)

    Kažimírová Viera

    2015-06-01

    Full Text Available Presented contribution deals with the verification of conditions for use of combustion products‘ heat, generated by combustion of wood in a fireplace used in a household. It is necessary to know the temperature behaviour of the fireplace to determine the adequacy of the technical solution for using combustion products‘ heat. The combustion products‘ temperature at the upper part of the chimney is 80-120 °C. The dew point value was established to be below 51 °C. The average observed value of combustion product velocity is 1.6 m s-1. The volume flow rate of combustion products is 12 m3 h-1. Measured values allow for effective solution of the use of combustion products‘ heat.

  12. Effect of Conditioner on Dewaterability of Sewage Sludge | Obianyo ...

    African Journals Online (AJOL)

    A model for dewaterability of conditioned sludge was derived based on data generated after dewaterability experiments using six sand drying beds. ... This modelB is good, but its deficiency lies in the fact that the coefficient of correlation between measured and calculated quantities of seepage at specified coagulant doses ...

  13. A steady state model for anaerobic digestion of sewage sludges ...

    African Journals Online (AJOL)

    A steady state model for anaerobic digestion of sewage sludge is developed that comprises three sequential parts – a kinetic part from which the % COD removal and ... and a carbonate system weak acid/base chemistry part from which the digester pH is calculated from the partial pressure of CO2 and alkalinity generated.

  14. Biogenic volatile compounds of activated sludge and their ...

    African Journals Online (AJOL)

    Heavy metals pollution is nowadays one of the most important environmental concerns. This paper illustrates the employment of the biogenic volatile compounds generated during the aerobic growth of activated sludge on raw domestic wastewater for heavy metals removal. Most of the tested metals even as individual or ...

  15. Supercritical water pyrolysis of sewage sludge.

    Science.gov (United States)

    Ma, Wenchao; Du, Guiyue; Li, Jian; Fang, Yuanhao; Hou, Li'an; Chen, Guanyi; Ma, Degang

    2017-01-01

    Municipal sewage sludge (SS) from wastewater treatment plant containing high water content (>85wt.%), lead to the difficulty of co-combustion with MSW or coal due to the high cost of drying. This study explores an alternative method by supercritical water (SCW) pyrolysis of sewage sludge (SS) in a high pressure reaction vessel. The effects of temperature and moisture content of SS on yield and composition of the products (bio-oil, bio char and non-condensable gas) were studied. A temperature of 385°C and moisture content of 85wt.% were found to be the optimum conditions for the maximum bio-oil production of 37.23wt.%, with a higher heating value of 31.08MJ/kg. In the optimum condition, the yields of aliphatic hydrocarbon and phenols were about 29.23wt.% and 12.51wt.%, respectively. The physical and chemical properties of bio-char were analyzed by using XRF and BET. Results of GC analyses of NCG showed that it has the maximum HHV of 13.39MJ/m 3 at 445°C and moisture content of 85wt.%. The reaction path from SS to bio-oil through SCW pyrolysis was given. Moreover, carbon balance was calculated for the optimal condition, and finding out that 64.27wt.% of the carbon content was transferred from SS to bio-oil. Finally, this work demonstrates that the SCW pyrolysis is a promising disposal method for SS. Copyright © 2016. Published by Elsevier Ltd.

  16. Potential gas releases from the bottom sludge layer

    International Nuclear Information System (INIS)

    Stewart, C.W.

    1994-04-01

    A layer of sludge about 50 inches deep may exist at the bottom of the tank that has not been mixed by the pump. This bottom sludge layer may be accumulating gas at a rate of 23 SCF/day, resulting in a basal level rise of 0.025 inches/day. At some point sufficient gas may accumulate to release spontaneously. Using reasonable assumptions about gas generation, waste properties and the mechanics of the release process, this may result in gas releases on the order of 1, 000 SCF

  17. Potential of Waste Water Sludge as Environmental-Friendly Manure after UV-Treatment

    OpenAIRE

    Laila Zafar; Asif Javed; Syed Shahid Ali; Zubair Anwar; Jabar Zaman Khan Khattak

    2012-01-01

    Due to exponential population increase in developing world, the wastewater and solid waste generation has tremendously increased and their management has become a serious health and environmental issue. A large amount of sewage sludge generated by sewage treatment plants however, can be re-used after proper segregation and treatment as fertilizer and for energy production. Hence, this study was carried out to find out the potential use of sludge produced at Islamabad Capital Territory (ICT) S...

  18. Rheology of Savannah River site tank 42 and tank 51 HLW radioactive sludges

    International Nuclear Information System (INIS)

    Ha, B.C.; Bibler, N.E.

    1996-01-01

    Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site (SRS) is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. The high activity radioactive wastes stored as caustic slurries at SRS result from the neutralization of acid waste generated from production of nuclear defense materials. During storage, the wastes separate into a supernate layer and a sludge layer. In the Defense Waste Processing Facility (DWPF) at SRS, the radionuclides from the sludge and supernate will be immobilized into borosilicate glass for long term storage and eventual disposal. Before transferring the waste from a storage tank to the DWPF, a portion of the aluminum in the waste sludge will be dissolved and the sludge will be extensively washed to remove sodium. Tank 51 and Tank 42 radioactive sludges represent the first batch of HLW sludge to be processed in the DWPF. This paper presents results of rheology measurements of Tank 51 and Tank 42 at various solids concentrations. The rheologies of Tank 51 and Tank 42 radioactive slurries were measured remotely in the Shielded Cells Operations (SCO) at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco RV-12 with an M150 measuring drive unit and TI sensor system. Rheological properties of the Tank 51 and Tank 42 radioactive sludges were measured as a function of weight percent solids. The weight percent solids of Tank 42 sludge was 27, as received. Tank 51 sludge had already been washed. The weight percent solids were adjusted by dilution with water or by concentration through drying. At 12, 15, and 18 weight percent solids, the yield stresses of Tank 51 sludge were 5, 11, and 14 dynes/cm2, respectively. The apparent viscosities were 6, 10, and 12 centipoises at 300 sec-1 shear rate, respectively

  19. Anaerobic Codigestion of Grass and Sewage Sludge: Laboratory Experiments and Feasibility Analysis.

    Science.gov (United States)

    Hidaka, Taira; Wang, Feng; Sakurai, Kensuke; Tsumori, Jun; Minamiyama, Mizuhiko

    2016-11-01

      Grass is drawing attention for its high potential for biogas production. Anaerobic digesters in wastewater treatment plants can be used for producing biogas by processing grass without having to invest in the construction of new treatment facilities. Batch and continuous digestion experiments were conducted to assess the feasibility of codigestion of sewage sludge and grass. The focus was on a thermophilic condition, starting-up from existing mesophilic anaerobic digestion of sewage sludge only. The batch and continuous experiments used two different sewage sludges. Results demonstrated a methane generation of approximately 0.2 normal liter-methane/g volatile solids-grass. The addition of grass did not affect the ammonia concentration and improved the dewaterability of the digested sludge. The start-up performance from mesophilic digested sewage sludge to thermophilic codigestion with grass was confirmed. A feasibility analysis demonstrated that codigestion is applicable in terms of energy recovery and greenhouse gas emission, depending on the transport distance of grass.

  20. Effect of low temperature on highly unsaturated fatty acid biosynthesis in activated sludge.

    Science.gov (United States)

    He, Su; Ding, Li-Li; Xu, Ke; Geng, Jin-Ju; Ren, Hong-Qiang

    2016-07-01

    Low temperature is a limiting factor for the microbial activity of activated sludge for sewage treatment plant in winter. Highly unsaturated fatty acid (UFA) biosynthesis, phospholipid fatty acid (PLFA) constituents and microbial structure in activated sludge at low temperature were investigated. Over 12 gigabases of metagenomic sequence data were generated with the Illumina HiSeq 2000 platform. The result showed 43.11% of phospholipid fatty acid (PLFA) in the activated sludge participated in UFA biosynthesis, and γ-Linolenic could be converted to Arachidonic acid at low temperature. The highly UFA biosynthesis in activated sludge was n-6 highly UFA biosynthesis, rather than n-3 highly UFA biosynthesis. The microbial community structures of activated sludge were analyzed by PLFA and high-throughput sequencing (HiSeq) simultaneously. Acidovorax, Pseudomonas, Flavobacterium and Polaromonas occupied higher percentage at 5°C, and genetic changes of highly UFA biosynthesis derived from microbial community structures change. Copyright © 2016. Published by Elsevier Ltd.

  1. Enhancement of exergy efficiency in combustion systems using flameless mode

    International Nuclear Information System (INIS)

    Hosseini, Seyed Ehsan; Wahid, Mazlan Abdul

    2014-01-01

    Highlights: • Exergy efficiency in flameless combustion mode is 13% more than conventional combustion. • The maximum exergy efficiency in flameless combustion mode is achieved when oxidizer contains 10% oxygen. • Exergy destruction of flameless combustion is maximized when CO 2 is used for dilution of oxidizer. - Abstract: An exergitic-based analysis of methane (CH 4 ) conventional and flameless combustion in a lab-scale furnace is performed to determine the rate of pollutant formation and the effective potential of a given amount of fuel in the various combustion modes. The effects of inlet air temperature on exergy efficiency and pollutant formation of conventional combustion in various equivalence ratios are analyzed. The rate of exergy destruction in different conditions of flameless combustion (various equivalence ratios, oxygen concentration in the oxidizer and the effects of diluent) are computed using three-dimensional (3D) computational fluid dynamic (CFD). Fuel consumption reduction and exergy efficiency augmentation are the main positive consequences of using preheated air temperature in conventional combustion, however pollutants especially NO x formation increases dramatically. Low and moderate temperature inside the chamber conducts the flameless combustion system to low level pollutant formation. Fuel consumption and exergy destruction reduce drastically in flameless mode in comparison with conventional combustion. Exergy efficiency of conventional and flameless mode is 75% and 88% respectively in stoichiometric combustion. When CO 2 is used for dilution of oxidizer, chemical exergy increases due to high CO 2 concentration in the combustion products and exergy efficiency reduces around 2% compared to dilution with nitrogen (N 2 ). Since the rate of irreversibilities in combustion systems is very high in combined heat and power (CHP) generation and other industries, application of flameless combustion could be effective in terms of pollutant

  2. Sizing an isolated wind-solar-fuel cell generation system based on the particle swarm optimization method; Dimensionamiento de un sistema de generacion aislado eolico-solar-celda de combustible basado en el metodo de optimizacion de enjambre de particulas

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Huerta, V; Ramirez-Arredondo, Juan M. [Universidad de Quintana Roo, Chetumal, Quintana Roo (Mexico)]. E-mail: vsanchez@gdl.cinvestav.mx; Arriaga-Hurtado, L. G. [CIDETEQ, Queretaro (Mexico)

    2009-09-15

    Sizing an electric energy system requires an analysis of investment, maintenance and operating costs. In the case of a generation system that uses renewable sources, optimal capacity becomes more complex compared to a conventional system, because of the randomness of renewable resources (wind, solar) and the still high costs of wind and photovoltage generator modules. This work presents the optimal sizing of a wind-solar-fuel cell generation system, minimizing the costs of the system while satisfying the energy demands of an isolated charge. The optimization method used is based on an evolutionary programming technique known as particle swarms (PSO-particle swarm optimization). The generation of energy with a hybrid system is discussed, based on the profile of insolation and wind availability at the site, with the objective of satisfying a specific electric demand. [Spanish] El dimensionamiento de un sistema de generacion de energia electrica requiere un analisis de los costos de inversion, mantenimiento y operacion. En el caso de un sistema de generacion que utiliza fuentes renovables la capacidad optima resulta mas compleja con respecto a un sistema convencional, debido a la aleatoriedad de los recursos renovables (eolico, solar), y a los aun altos costos de generadores eolicos y modulos fotovoltaicos. En este trabajo se presenta el dimensionamiento optimo de un sistema de generacion eolico-solar-celda de combustible minimizando los costos del sistema que satisfaga la energia demandada por una carga aislada. El metodo de optimizacion utilizado esta basado en una tecnica de programacion evolutiva conocida como enjambre de particulas (PSO por sus siglas en ingles: particle swarm optimization). Se plantea la generacion de energia del sistema hibrido con base a la insolacion y el perfil del viento disponible en sitio, con objeto de satisfacer una demanda electrica determinada.

  3. Monitoring of sludge dewatering equipment by image classification

    Science.gov (United States)

    Maquine de Souza, Sandro; Grandvalet, Yves; Denoeux, Thierry

    2004-11-01

    Belt filter presses represent an economical means to dewater the residual sludge generated in wastewater treatment plants. In order to assure maximal water removal, the raw sludge is mixed with a chemical conditioner prior to being fed into the belt filter press. When the conditioner is properly dosed, the sludge acquires a coarse texture, with space between flocs. This information was exploited for the development of a software sensor, where digital images are the input signal, and the output is a numeric value proportional to the dewatered sludge dry content. Three families of features were used to characterize the textures. Gabor filtering, wavelet decomposition and co-occurrence matrix computation were the techniques used. A database of images, ordered by their corresponding dry contents, was used to calibrate the model that calculates the sensor output. The images were separated in groups that correspond to single experimental sessions. With the calibrated model, all images were correctly ranked within an experiment session. The results were very similar regardless of the family of features used. The output can be fed to a control system, or, in the case of fixed experiment conditions, it can be used to directly estimate the dewatered sludge dry content.

  4. Leachability of fired clay brick incorporating with sewage sludge waste

    Science.gov (United States)

    Kadir, Aeslina Abdul; Salim, Nurul Salhana Abdul; Sarani, Noor Amira; Rahmat, Nur Aqma Izurin; Abdullah, Mohd Mustafa Al Bakri

    2017-09-01

    Sewage sludge is sewerage from wastewater treatment plants that generates millions tons of sludge ever year. Regarding this activity, it causes lack management of waste which is harmful to the surrounding conditions. Therefore, this study is focuses on the incorporation of sewage sludge waste into fired clay brick to provide an option of disposal method, producing adequate quality of brick as well as limiting the heavy metal leachability to the environment. Sewage sludge brick (SSB) mixtures were incorporated with 0%, 1%, 5%, 10%, 20% and 30% of sewage sludge waste (SSW). Heavy metals of crushed SSB were determined by using Toxicity Characteristic Leaching Procedure (TCLP) according to Method 1311 of United State Environment Protection Agency (USEPA) standard. From the results obtained, up to 20% of SSW could be incorporated into fired clay brick and comply with the USEPA standard. Therefore, this study revealed that by incorporating SSW into fired clay brick it could be an alternative method to dispose the SSW and also could act as a replacement material for brick manufacturing with appropriate mix and design.

  5. INTEC SBW Solid Sludge Surrogate Recipe and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Maio, Vince; Janikowski, Stuart; Johnson, Jim; Maio, Vince; Pao, Jenn-Hai

    2004-06-01

    A nonhazardous INTEC tank farm sludge surrogate that incorporated metathesis reactions to generate solids from solutions of known elements present in the radioactive INTEC tank farm sodium-bearing waste sludges was formulated. Elemental analyses, physical property analyses, and filtration testing were performed on waste surrogate and tank farm waste samples, and the results were compared. For testing physical systems associated with moving the tank farm solids, the surrogate described in this report is the best currently available choice. No other available surrogate exhibits the noted similarities in behavior to the sludges. The chemical morphology, particle size distribution, and settling and flow characteristics of the surrogate were similar to those exhibited by the waste sludges. Nonetheless, there is a difference in chemical makeup of the surrogate and the tank farm waste. If a chemical treatment process were to be evaluated for final treatment and disposition of the waste sludges, the surrogate synthesis process would likely require modification to yield a surrogate with a closer matching chemical composition.

  6. The sustainable utilization of malting industry wastewater biological treatment sludge

    Science.gov (United States)

    Vasilenko, T. A.; Svintsov, A. V.; Chernysh, I. V.

    2018-01-01

    The article deals with the research of using the sludge from malting industry wastewater’s biological treatment and the calcium carbonate slurry as organo-mineral fertilizing additives. The sludge, generated as a result of industrial wastewater biological treatment, is subject to dumping at solid domestic waste landfills, which has a negative impact on the environment, though its properties and composition allow using it as an organic fertilizer. The physical and chemical properties of both wastes have been studied; the recommendations concerning the optimum composition of soil mix, containing the above-mentioned components, have been provided. The phytotoxic effect on the germination capacity and sprouts of cress (Lepidium sativum), barley (Hordéum vulgáre) and oats (Avena sativa) in soil mixes has been determined. The heavy metals and arsenic contents in the sludge does not exceed the allowable level; it is also free of pathogenic flora and helminthes.

  7. Impact of the fuel cost in the electric generation cost by nuclear means; Impacto del costo del combustible en el costo de generacion electrica por medios nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez S, J.R.; Alonso V, G.; Gomez R, M.C.; Palacios H, J. [ININ, Carretera Mexico-Toluca Km. 36.5, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jrrs@nuclear.inin.mx

    2007-07-01

    In recent years, the uranium cost has been increased in the international market due to a countless of factors like they are: increase of the demand, the turnaround of the nuclear energy in some Asian countries, the decrease of the offer due to problems in the mining for their extraction, etc. These increments impact the costs of electric generation in the concept of fuel, presently work is calculated that order is the prospective impact when the costs of the uranium and the services of the fuel cycle are increased to the speed that one has come increasing, and an increase is postulated beyond the 100 usd/lb U{sub 3}O{sub 8}, being also calculated its impact in the total cost of electric generation by nuclear means. (Author)

  8. Combustion Byproducts Recycling Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    Ashlines: To promote and support the commercially viable and environmentally sound recycling of coal combustion byproducts for productive uses through scientific research, development, and field testing.