Solutions to microplastic pollution - Removal of microplastics from wastewater effluent with advanced wastewater treatment technologies.

Science.gov (United States)

Talvitie, Julia; Mikola, Anna; Koistinen, Arto; Setälä, Outi

2017-10-15

Conventional wastewater treatment with primary and secondary treatment processes efficiently remove microplastics (MPs) from the wastewater. Despite the efficient removal, final effluents can act as entrance route of MPs, given the large volumes constantly discharged into the aquatic environments. This study investigated the removal of MPs from effluent in four different municipal wastewater treatment plants utilizing different advanced final-stage treatment technologies. The study included membrane bioreactor treating primary effluent and different tertiary treatment technologies (discfilter, rapid sand filtration and dissolved air flotation) treating secondary effluent. The MBR removed 99.9% of MPs during the treatment (from 6.9 to 0.005 MP L -1 ), rapid sand filter 97% (from 0.7 to 0.02 MP L -1 ), dissolved air flotation 95% (from 2.0 to 0.1 MP L -1 ) and discfilter 40-98.5% (from 0.5 - 2.0 to 0.03-0.3 MP L -1 ) of the MPs during the treatment. Our study shows that with advanced final-stage wastewater treatment technologies WWTPs can substantially reduce the MP pollution discharged from wastewater treatment plants into the aquatic environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of oil sands effluent on cattail and clover: photosynthesis and the level of stress proteins

Energy Technology Data Exchange (ETDEWEB)

Crowe, A.U.; Han, B.; Kermode, A.R.; Bendell-Young, L.I.; Plant, A.L. [Simon Fraser University, Burnaby (Canada). Dept. of Biological Sciences

2001-07-01

The oil sands industry located in northeastern Alberta, Canada, generates large volumes of effluent characterized by a high level of dissolved ions and naphthenic acids. The dikes used to store the effluent seep, creating wetlands which are subsequently invaded by obligate wetland flora such as cattail (Typha latifolia L.). The appearance of these wetlands prompted the oil sands industry to consider wetlands as part of their reclamation strategy. However, to ensure long-term viability of such wetlands, the response of the flora to the industrial effluent needed to be determined. To this end, apparent photosynthesis (APS), the level of ribulose-1,5-bisphosphate carboxylase (RuBisCo) large subunit, dehydrin-related polypeptides, and protein disulphide isomerase (PDI) were evaluated in cattail and alsike clover plants (Trifolium hybridum L.) exposed to the oil sands effluent. APS measured in plants impacted by oil sands effluent was significantly higher than that of plants in the non-impacted off-site location. Among the on-site locations, plants growing in the natural wetlands site had higher APS compared to all other sites. The level of RuBisCo was not increased in cattail or clover growing in effluent-contaminated sites indicating that enhanced photosynthesis was not due to greater levels of this enzyme. Dehydrin-related polypeptides were detected only in the roots of cattail and were absent in clover. The polypeptide profile was altered in cattail exposed to oil sands effluent indicating that they were responding to an osmotic stress. The level of PDI was unaffected in the leaves of cattail regardless of the nature of the effluent to which they were exposed. Overall, the data indicate that cattail and clover are adapted to the oil sands effluent, although further studies are needed to assess their long-term ability to survive in the presence of this anthropogenic stress. (Author)

K West Basin Sand Filter Backwash Sample Analysis

Energy Technology Data Exchange (ETDEWEB)

Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smoot, Margaret R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Coffey, Deborah S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pool, Karl N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-03-01

A sand filter is used to help maintain water clarity at the K West Basin where highly radioactive sludge is stored. Eventually that sand filter will require disposal. The radionuclide content of the solids trapped in the sand filter will affect the selection of the sand filter disposal pathway. The Pacific Northwest National Laboratory (PNNL) was contracted by the K Basin Operations & Plateau Remediation Project (operations contractor CH2M Hill) to analyze the radionuclide content of the solids collected from the backwash of the K West Basin sand filter. The radionuclide composition in the sand filter backwash solids will be used by CH2M Hill to determine if the sand filter media and retained sludge solids will be designated as transuranic waste for disposal purposes or can be processed through less expensive means. On October 19, 2015, K Basin Operations & Plateau Remediation Project staff backwashed the sand filter into the North Load-Out Pit (NLOP) and immediately collected sample slurry from a sampling tube positioned 24 in. above the NLOP floor. The 764 g sand filter backwash slurry sample, KW-105 SFBW-001, was submitted to PNNL for analysis on October 20, 2015. Solids from the slurry sample were consolidated into two samples (i.e., a primary and a duplicate sample) by centrifuging and measured for mass (0.82 g combined – wet centrifuged solids basis) and volume (0.80 mL combined). The solids were a dark brown/orange color, consistent with iron oxide/hydroxide. The solids were dried; the combined dry solids mass was 0.1113 g, corresponding to 0.0146 weight percent (wt%) solids in the original submitted sample slurry. The solids were acid-digested using nitric and hydrochloric acids. Insoluble solids developed upon dilution with 0.5 M HNO₃, corresponding to an average 6.5 wt% of the initial dry solids content. The acid digestate and insoluble solids were analyzed separately by gamma spectrometry. Nominally, 7.7% of the ⁶⁰Co was present

Evaluate of head loss, sediment value and copper removal in sand media (rapid sand filter

Directory of Open Access Journals (Sweden)

Daneshi Navab

2014-06-01

Full Text Available Along with the technology development and increasing consumption of water resources, we are experiencing low qualities in the mentioned resources. Copper brings about serious environment al pollution, threatening human health and ecosystem. This metal found variously in water resources and industrial activities. Therefore, it needs to treat the water resources from these excessive amounts. Different methods have used for this reason but the most used method during recent years has been the absorption by economic absorbers such as sand. Rapid sand filters usually used in water and wastewater treatment plants for water clarification. In this research, a single layer gravity rapid sand filter has used to reduce different concentrations of copper. sediment value and head loss arising in filter media is simulated by using combination of Carman-Kozeny, Rose and Gregory models in different discharges of rapid sand filter. Results have shown that with increasing in discharge and decreasing in input copper concentration, arriving time to given head loss, is increasing. In addition, results demonstrated that with increasing in copper concentration in influent, removal efficiency is decreasing somewhat. Results of this research can applied in an appropriate design of rapid sand filter to copper removal, a prediction of rapid sand filter ability to copper removal and an estimation of arising head loss during filter work thus evaluating of time interval backwash. DOI: http://dx.doi.org/10.3126/ije.v3i2.10641 International Journal of the Environment Vol.3(2 2014: 276-286

Replicating the microbial community and water quality performance of full-scale slow sand filters in laboratory-scale filters.

Science.gov (United States)

Haig, Sarah-Jane; Quince, Christopher; Davies, Robert L; Dorea, Caetano C; Collins, Gavin

2014-09-15

Previous laboratory-scale studies to characterise the functional microbial ecology of slow sand filters have suffered from methodological limitations that could compromise their relevance to full-scale systems. Therefore, to ascertain if laboratory-scale slow sand filters (L-SSFs) can replicate the microbial community and water quality production of industrially operated full-scale slow sand filters (I-SSFs), eight cylindrical L-SSFs were constructed and were used to treat water from the same source as the I-SSFs. Half of the L-SSFs sand beds were composed of sterilized sand (sterile) from the industrial filters and the other half with sand taken directly from the same industrial filter (non-sterile). All filters were operated for 10 weeks, with the microbial community and water quality parameters sampled and analysed weekly. To characterize the microbial community phyla-specific qPCR assays and 454 pyrosequencing of the 16S rRNA gene were used in conjunction with an array of statistical techniques. The results demonstrate that it is possible to mimic both the water quality production and the structure of the microbial community of full-scale filters in the laboratory - at all levels of taxonomic classification except OTU - thus allowing comparison of LSSF experiments with full-scale units. Further, it was found that the sand type composing the filter bed (non-sterile or sterile), the water quality produced, the age of the filters and the depth of sand samples were all significant factors in explaining observed differences in the structure of the microbial consortia. This study is the first to the authors' knowledge that demonstrates that scaled-down slow sand filters can accurately reproduce the water quality and microbial consortia of full-scale slow sand filters. Copyright © 2014 Elsevier Ltd. All rights reserved.

Penggunaan Unit Slow Sand Filter, Ozon Generator dan Rapid Sand Filter Skala Rumah Tangga Untuk Meningkatkan Kualitas Air Sumur Dangkal Menjadi Air Layak Minum (Parameter Zat Organik dan Deterjen

Directory of Open Access Journals (Sweden)

Anindya Prawita Sari

2014-09-01

Full Text Available Air sumur merupakan air tanah yang sering kali digunakan masyarakat untuk aktivitas sehari-hari. Air sumur dengan kadar organik dan deterjen tinggi tidak layak dikonsumsi masyarakat karena dapat menyebabkan berbagai macam penyakit. Selain itu, adanya zat organik dan deterjen mempengaruhi warna dan bau air sumur sehingga tidak layak konsumsi. Slow sand filter merupakan unit pengolahan yang mampu meremoval zat organik pada air. Slow sand filter dan rapid sand filter tidak menggunakan bahan kimia dalam proses pengolahan sehingga lebih ekonomis dan efektif. Sedangkan ozon, efektif digunakan untuk meremoval zat organik yang ada dalam air dengan mengubah rantai zat organik menjadi lebih sederhana. Tujuan penelitian ini adalah untuk mengetahui keefektifan penggunaan slow sand filter, ozon generator dan rapid sand filter dalam menyisihkan beban deterjen dan zat organik pada air sumur. Hasil penelitian menunjukkan bahwa efisiensi removal pada unit slow sand filter untuk beban organik dan deterjen sebesar 57,6% dan 60,5 %, pada unit ozonasi sebesar 47,4% dan 17,5%, dan pada unit rapid sand filter sebesar 50,0% dan 50,9 %.

Transport of nanoparticles with dispersant through biofilm coated drinking water sand filters.

Science.gov (United States)

Li, Zhen; Aly Hassan, Ashraf; Sahle-Demessie, Endalkachew; Sorial, George A

2013-11-01

This article characterizes, experimentally and theoretically, the transport and retention of engineered nanoparticles (NP) through sand filters at drinking water treatment plants (DWTPs) under realistic conditions. The transport of four commonly used NPs (ZnO, CeO2, TiO2, and Ag, with bare surfaces and coating agents) through filter beds filled with sands from either acid washed and calcined, freshly acquired filter media, and used filter media from active filter media, were investigated. The study was conducted using water obtained upstream of the sand filter at DWTP. The results have shown that capping agents have a determinant importance in the colloidal stability and transport of NPs through the different filter media. The presence of the biofilm in used filter media increased adsorption of NPs but its effects in retaining capped NPs was less significant. The data was used to build a mathematical model based on the advection-dispersion equation. The model was used to simulate the performance of a scale-up sand filter and the effects on filtration cycle of traditional sand filtration system used in DWTPs. Published by Elsevier Ltd.

Submerged Pond Sand Filter-A Novel Approach to Rural Water Supply

DEFF Research Database (Denmark)

Øhlenschlæger, Mia; Christensen, Sarah Christine Boesgaard; Bregnhøj, Henrik

2016-01-01

This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water...... to a rural Indian village. The filter has functioned with minimal maintenance for five years without being subject to the typical scraping off and changing of sand as needed in traditional slow sand filters every few months. This five-year study showed bacterial removal efficiency of 97% on average...... to 10 CFU/100 mL on average compared to shorter pumping intervals (5 min). Though the treated water did not comply with the World Health Organization standards of 0 CFU/100 mL, the filter significantly improved water quality and provided one of the best sources of drinkable water in a water...

Stratification of nitrification activity in rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Musovic, Sanin

2013-01-01

Rapid sand filters used in groundwater treatment remove ammonium, iron and manganese from the water. Ammonium is removed biologically by nitrifying microorganisms attached on the sand surface. Nitrification kinetics and activity is strongly affected by filter design and operation, which are the key...... and maximum nitrification capacity are derived and used to quantify nitrification activity. Nitrification activity was concentrated at the top 10 cm of filter depth, and maximum nitrification capacity was 7 g NH4+-N/ m3 sand/h compared with 0.8-0.4 g NH4+-N/ m3 sand/h in the middle and bottom layers. A water...... of this study is to investigate nitrification activity in a rapid sand filter, with focus on its homogeneity and how it relates to filter performance. Two groundwater treatment plants in Denmark were selected for the experimental investigations. Plant 1 operates a single line of pre and after filters and has...

Removal method of radium in mine water by filter sand

International Nuclear Information System (INIS)

Taki, Tomihiro; Naganuma, Masaki

2003-01-01

Trace radium is contained in mine water from the old mine road in Ningyo-Toge Environmental Engineering Center, JNC. We observed that filter sand with hydrated manganese oxide adsorbed radium in the mine water safely for long time. The removal method of radium by filter sand cladding with hydrated manganese oxide was studied. The results showed that radium was removed continuously and last for a long time from mine water with sodium hypochlorite solution by passing through the filter sand cladding with hydrated manganese. Only sodium hypochlorite solution was used. When excess of it was added, residue chlorine was used as chlorine disinfection. Filter sand cladding with hydrated manganese on the market can remove radium in the mine water. The removal efficiency of radium is the same as the radium coprecipitation method added with barium chloride. The cost is much lower than the ordinary methods. Amount of waste decreased to about 1/20 of the coprecipitation method. (S.Y.)

Removal of nitrate, ammonia and phosphate from aqueous solutions in packed bed filter using biochar augmented sand media

Directory of Open Access Journals (Sweden)

El Hanandeh Ali

2017-01-01

Full Text Available Nutrients from wastewater are a major source of pollution because they can cause significant impact on the ecosystem. Accordingly, it is important that the nutrient concentrations are kept to admissible levels to the receiving environment. Often regulatory limits are set on the maximum allowable concentrations in the effluent. Therefore, wastewater must be treated to meet safe levels of discharge. In this study, laboratory investigation of the efficiency of packed bed filters to remove nitrate, ammonium and phosphate from aqueous solutions were conducted. Sand and sand augmented with hydrochloric acid treated biochar (SBC were used as packing media. Synthetic wastewater solution was prepared with PO43−, NO3−, NH4+ concentrations 20, 10, 50 mg/L, respectively. Each experiment ran for a period of five days; samples from the effluent were collected on alternate days. All experiments were duplicated. Over the experiment period, the average removal efficiency of PO43−, NO3−, NH4+ were 99.2%, 72.9%, 96.7% in the sand packed columns and 99.2%, 82.3%, 97.4% in the SBC packed columns, respectively. Although, the presence of biochar in the packing media had little effect on phosphate and ammonium removal, it significantly improved nitrate removal.

Microbial pesticide removal in rapid sand filters for drinking water treatment – Potential and kinetics

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

2014-01-01

Filter sand samples, taken from aerobic rapid sand filters used for treating groundwater at three Danish waterworks, were investigated for their pesticide removal potential and to assess the kinetics of the removal process. Microcosms were set up with filter sand, treated water, and the pesticides...... or metabolites mecoprop (MCPP), bentazone, glyphosate and p-nitrophenol were applied in initial concentrations of 0.03–2.4 μg/L. In all the investigated waterworks the concentration of pesticides in the water decreased – MCPP decreased to 42–85%, bentazone to 15–35%, glyphosate to 7–14% and p-nitrophenol 1....../L) increased from 0.21%/g filter sand to 0.75%/g filter sand, when oxygen availability was increased from 0.28 mg O2/g filter sand to 1.09 mg O2/g filter sand. Bentazone was initially cleaved in the removal process. A metabolite, which contained the carbonyl group, was removed rapidly from the water phase...

A Simple Slow-Sand Filter for Drinking Water Purification

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K. O. Yusuf

2017-04-01

Full Text Available Water-borne diseases are commonly encountered when pathogen-contaminated water is consumed. In rural areas, water is usually obtained from ponds, open shallow wells, streams and rain water during rainy season. Rain water is often contaminated by pathogens due to unhygienic of physical and chemical conditions of the roofs thereby making it unsafe for consumption. A simple slow sand filter mechanism was designed and fabricated for purification of water in rural areas where electricity is not available to power water purification devices. Rain water samples were collected from aluminum roof, galvanized roof and thatched roof. The waters samples were allowed to flow through the slow sand filter. The values of turbidity, total dissolved solids, calcium, nitrite, faecal coliform and total coliform from unfiltered water through thatched roof were 0.92 NTU, 27.23 mg/l, 6 mg/l, 0.16 mg/l, 5cfu/100ml and 6.0 cfu/100ml, respectively while the corresponding values for slow sand filter from thatched roof were 0.01 NTU, 0.23 mg/l, 2.5 mg/l, 0.1 mg/l, 0 cfu/100ml and 0 cfu/100ml, respectively. The values of turbidity, total dissolved solid, nitrite, calcium, faecal coliform and total coliform from unfiltered water for aluminum roof were 0.82 NTU, 23.68 mg/l, 2.70 mg/l, 1.0 mg/l, 4 cfu/100ml and 4cfu/100ml, respectively while the corresponding values for slow sand filter were 0.01 NTU, 0.16 mg/l, 0.57 mg/l, 0.2 mg/l, 0 cfu/100ml and 0 cfu/100ml, respectively. The values obtained for galvanized roof were also satisfactory. The slow sand filter is recommended for used in rural areas for water purification to prevent risk of water-borne diseases.

COLLOIDS IN SEPTIC TANK EFFLUENT AND THEIR INFLUENCE ON FILTER PERMEABILITY

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Marcin Spychała

2015-09-01

Full Text Available The aim of the study was to evaluate the content of colloids in septic tank effluent and their impact on textile filter permeability. Measurements were performed on septic tank effluent without suspended solids but containing colloids and without colloids - including only dissolved substances (filtered by micro-filters and centrifuged. The study was conducted on unclogged and clogged textile filter coupons. During the study the following measurements were determined: turbidity, chemical oxygen demand and hydraulic conductivity of textile filter coupons. The colloid size range was assumed to be less than 1.2 microns according to the literature. Despite the relatively low content in the septic tank effluent the colloids played an important role in the clogging process. Both the filtering media, filled with low (unclogged and high content of biomass (clogged were sensitive to the clogging process of colloid acceleration due to the possibility of small diameter pore closure and oxygen access termination. Moreover, small size pores were probably sensitive to closing or bridging by small size colloidal particles.

Evaluation of the MF/UF Performance for the Reuse of Sand Filter Backwash Water from Drinking Water Treatment Plants

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Neda Shirzadi

2015-05-01

Full Text Available The aim of this study was to investigate the application of micro-filtration and ultra-filtration membrane systems in order to improve the physical and microbial quality and the reuse of backwash water from the sand filter units in water treatment plants. The backwash water from filters makes up for 3 to 5 percent of the total water treated, which is disposed in most WTPs. However, the treatment and reuse of the backwash water is more admissible from technical and economic viewpoints, especially in view of the present water scarcity. For the purposes of this study, use was made of membrane modules of micro- and ultra-filters on a pilot scale. The micro-filter employed consisted of a polypropylene membrane module with a porosity of 1 micron in size and a fiberglass module with a porosity of 5 microns. The ultra-filter was made of PVC hollow fiber with a molecular weight of 100,000 Dalton. In order to feed the two pilots, backwash water from a sand filter was collected from one of the WTPs in Tehran. After samples were taken from the backwash water, the physical and microbial removal efficiency was periodically evaluated based on the standard method and the micro-filtration, ultra-filtration, and combined MF/UF processes were compared with respect to their performance. The results indicate that the combined MF/UF process is able to decrease turbidity, MPN, COD, TSS, and Fe with efficiency values of 99.9, 100, 61.5, 99.9 and 98.8 percent, respectively. Overall, the findings confirmed the technical capabilities of this method for the recovery and reuse of the effluent produced in the backwashing mechanism of sand filters in WTPs.

40 CFR 141.551 - What strengthened combined filter effluent turbidity limits must my system meet?

Science.gov (United States)

2010-07-01

... effluent turbidity limits must my system meet? 141.551 Section 141.551 Protection of Environment... Effluent Requirements § 141.551 What strengthened combined filter effluent turbidity limits must my system meet? Your system must meet two strengthened combined filter effluent turbidity limits. (a) The first...

Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates

OpenAIRE

Phuong, NguyenThi; Andisetiawan, Anugrah; Van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung

2016-01-01

Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has be...

Sorption and desorption of arsenic to ferrihydrite in a sand filter.

Science.gov (United States)

Jessen, Soren; Larsen, Flemming; Koch, Christian Bender; Arvin, Erik

2005-10-15

Elevated arsenic concentrations in drinking water occur in many places around the world. Arsenic is deleterious to humans, and consequently, As water treatment techniques are sought. To optimize arsenic removal, sorption and desorption processes were studied at a drinking water treatment plant with aeration and sand filtration of ferrous iron rich groundwater at Elmevej Water Works, Fensmark, Denmark. Filter sand and pore water were sampled along depth profiles in the filters. The sand was coated with a 100-300 microm thick layer of porous Si-Ca-As-contaning iron oxide (As/Fe = 0.17) with locally some manganese oxide. The iron oxide was identified as a Si-stabilized abiotically formed two-line ferrihydrite with a magnetic hyperfine field of 45.8 T at 5 K. The raw water has an As concentration of 25 microg/L, predominantly as As(II). As the water passes through the filters, As(III) is oxidized to As(V) and the total concentrations drop asymptotically to a approximately 15 microg/L equilibrium concentration. Mn is released to the pore water, indicating the existence of reactive manganese oxides within the oxide coating, which probably play a role for the rapid As(III) oxidation. The As removal in the sand filters appears controlled by sorption equilibrium onto the ferrihydrite. By addition of ferrous chloride (3.65 mg of Fe(II)/L) to the water stream between two serially connected filters, a 3 microg/L As concentration is created in the water that infiltrates into the second sand filter. However, as water flow is reestablished through the second filter, As desorbs from the ferrihydrite and increases until the 15 microg/L equilibrium concentration. Sequential chemical extractions and geometrical estimates of the fraction of surface-associated As suggest that up to 40% of the total As can be remobilized in response to changes in the water chemistry in the sand filter.

Application of Self Cleaning Rapid Sand Filter in Water Treatment

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Ali Reza Rahmani

2005-08-01

Full Text Available Rapid sand filter is one of the most important units in the water treatment plants. It has some difficulties in operation such as backwashing. For the solving of this problem a rapid sand filter has designed and built with the self-cleaning backwashing system. This system consist of 3 main constituents; one galvanized siphon and two galvanized steel tanks. One of them is used for filtration and the other used for the storage of filtrated water in elevation for backwashing the system. Water enter from upside of the filter through the inlet pipe, and collected from the under drainage pipe. Then filter water conduct to the storage tank and exit from outlet pipe. In the beginning, the head loss was low, but because of bed clogging by suspended solids, it increases gradually to the designed head loss (1.2m. Then the system is outed of the service automatically and the backwash is began. The main data for the design of system selected from the hydraulic rules of siphons and rapid sand filter criteria. After essential calculations it was constructed and was started operation. For the hydraulic studies a known volume of storage tank was selected and the time needed for the fill (in filtration stage and empty (in backwash stage of water volume with volumetric method were measured. In hydraulic studies the filter surface rate (SOR was selected about 5-7.5m3/m2/hr (1.39-2.08 lit/sec and the flow of water in siphon, during the backwashing was measured 8.7 lit/sec. It can be seen that the siphon passes 4-6 times the inlet raw water thus a negative pressure will created in the siphon which causes the water above the sand bed to be discharged automatically and rinse water from elevated tank flow under the sand bed and back wash it. So according to this study self cleaning rapid sand filter is very useful for water filtration, especially in small population community. The construction of system is rapid, simple and economic.

Processes of microbial pesticide degradation in rapid sand filters for treatment of drinking water

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

Aerobic rapid sand filters for treatment of groundwater at waterworks were investigated for the ability to remove pesticides. The potential, kinetics and mechanisms of microbial pesticide removal was investigated in microcosms consisting of filter sand, treated water and pesticides in initial...... concentrations of 0.04-2.4 μg/L. The pesticides were removed from the water in microcosms with filter sand from all three investigated sand filters. Within the experimental periode of six to 13 days, 65-85% of the bentazone, 86-93% of the glyphosate, 97-99% of the p-nitrophenol was removed from the water phase...

Microbial degradation of pesticides in rapid sand filters for treatment of drinking water

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Albrechtsen, Hans-Jørgen

2014-01-01

In Denmark drinking water supply is based on groundwater which is treated by aeration followed by filtration in rapid sand filters. Unfortunately pesticide contamination of the groundwater poses a threat to the water supply, since the simple treatment process at the waterworks is not considered...... to remove pesticides from the water phase and pesticides are detected in 24% of the active Danish waterworks wells. This study aimed at investigating the potential of microbial pesticide removal in rapid sand filters for drinking water treatment. Removal of the pesticides MCPP, bentazone, glyphosate...... and the degradation compound p-nitrophenol was investigated in the rapid sand filters at Islevbro and Sjælsø waterworks plant I and II. Microcosms were set up with sand from rapid sand filters, water and an initial pesticide concentration of 0.03-0.38 μg/L. In all the investigated waterworks the concentration...

Optimizing nitrification in biological rapid sand filters for drinking water production

DEFF Research Database (Denmark)

Albrechtsen, Hans-Jørgen; Smets, Barth F.; Lee, Carson Odell

Addition of phosphate or trace metals or better management e.g. in terms of anmonium load can improve the nitrification rate and efficiency in biological rapid sand filters.......Addition of phosphate or trace metals or better management e.g. in terms of anmonium load can improve the nitrification rate and efficiency in biological rapid sand filters....

Biodegradation of gasoline compounds (BTEX) in a water works sand filter

DEFF Research Database (Denmark)

Arvin, Erik; Engelsen, P.; Sebber, U.

2004-01-01

Various chemical compounds including aromatic gasoline compounds frequently contaminate drinking water wells in urban areas. Because ground water treatment is simple, usually consisting of aeration/stripping and sand-filtration, it is of significant interest to know the ability of the conventional...... treatment to remove the chemical contaminants. The removal of gasoline compounds was investigated in a two-stage pilot scale sand filter, each with a filter depth of 0.8-1 m and with a filtration rate of 7.6 m/h. The concentrations of aromatic compounds were in the range 7-15 mu g/L, which are realistically...... sand grains). Influent iron concentrations in the range 0-4 mg/L and backwashing did not adversely affect the biodegradation of hydrocarbons. This study has shown that a conventional biological active sand filter can act as an efficient barrier against gasoline compounds, thereby saving the consumer...

Post-treatment of anaerobic reactor effluent using coagulation/oxidation followed by double filtration.

Science.gov (United States)

Cavallini, Grasiele Soares; de Sousa Vidal, Carlos Magno; de Souza, Jeanette Beber; de Campos, Sandro Xavier

2016-04-01

This study evaluates the efficacy of a sanitary sewage treatment system, proposing post-treatment of the effluent generated by the upflow anaerobic sludge blanket UASB reactor, through a Fenton coagulation/oxidation ((ferric chloride (FC) or ferrous sulfate (FS) and peracetic acid (PAA)), followed by a double filtration system, composed of a gravel ascending drainage filter and a sand descending filter. Following the assessment of treatability, the system efficiency was evaluated using physicochemical and microbiological parameters. In all treatments performed in the pilot unit, total suspended solids (TSS) were completely removed, leading to a decrease in turbidity greater than 90% and close to 100% removal of total phosphorous. In the FC and PAA combination, the effluent was oxygenated prior to filtration, enabling a more significant removal of biochemical oxygen demand (BOD), which characterizes aerobic degradation even in a quick sand filter. The treatments carried out in the presence of the PAA oxidizing agent showed a more significant bleaching of the effluent. Concerning the microbiological parameters, the simultaneous use of PAA and FC contributed to the partial inactivation of the assessed microorganisms. A 65% recovery of the effluent was obtained with the proposed treatment system, considering the volume employed in filter backwashing.

Microalgal Cultivation in Secondary Effluent: Recent Developments and Future Work

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Junping Lv

2017-01-01

Full Text Available Eutrophication of water catchments and the greenhouse effect are major challenges in developing the global economy in the near future. Secondary effluents, containing high amounts of nitrogen and phosphorus, need further treatment before being discharged into receiving water bodies. At the same time, new environmentally friendly energy sources need to be developed. Integrating microalgal cultivation for the production of biodiesel feedstock with the treatment of secondary effluent is one way of addressing both issues. This article provides a comprehensive review of the latest progress in microalgal cultivation in secondary effluent to remove pollutants and accumulate lipids. Researchers have discovered that microalgae remove nitrogen and phosphorus effectively from secondary effluent, accumulating biomass and lipids in the process. Immobilization of appropriate microalgae, and establishing a consortium of microalgae and/or bacteria, were both found to be feasible ways to enhance pollutant removal and lipid production. Demonstrations of pilot-scale microalgal cultures in secondary effluent have also taken place. However there is still much work to be done in improving pollutants removal, biomass production, and lipid accumulation in secondary effluent. This includes screening microalgae, constructing the consortium, making use of flue gas and nitrogen, developing technologies related to microalgal harvesting, and using lipid-extracted algal residues (LEA.

REDUCTION OF SOIL INFILTRATION AREA THANKS TO THE WASTEWATER SECONDARY TREATMENT FILTERS

Directory of Open Access Journals (Sweden)

Marcin Spychała

2016-05-01

Full Text Available The aim of the article was to determine the feasibility and advisability of the use of secondary filters applied before discharge of wastewater into the ground in the context of the fulfillment of the conditions of the current Regulation of the Minister of Environment of 18 November 2014 on the conditions to be met during the discharge of wastewater into the water or the ground and on substances particularly harmful to the aquatic environment. Due to expected in practice, an application and popularity, as compared variants, reactors having a very simple construction were used. The average values of removal of BOD5, COD and total suspended solids for three secondary filters technologies: biological trickling filter with natural ventilation, sand filter and nonwoven filter were compared. Additionally, as a fourth option a simple mathematical model has been presented. This model allows to estimate of BOD5 at the outflow from biological trickling filter and to verify the empirical data. Despite a large usefulness, it is rarely used in our country. It has been found the possibility of reduction of the infiltration area (surface area after reduction is 38–63% of the initial value due to the application of secondary filters. In the case of a high initial demand of the terrain area for drainage localization the benefit in costs resulting from the reduction (several thousand of PLN or may even significantly exceed the cost of buying and installing a cheap secondary filter. In addition, reduction the occupied area of the lot (in extreme cases up to 100 m2 by using the secondary filter allows to use the unoccupied space for other purposes, and thus gives additional economic advantage.

Arsenic removal from drinking water by a household sand filter in Vietnam--effect of filter usage practices on arsenic removal efficiency and microbiological water quality.

Science.gov (United States)

Nitzsche, Katja Sonja; Lan, Vi Mai; Trang, Pham Thi Kim; Viet, Pham Hung; Berg, Michael; Voegelin, Andreas; Planer-Friedrich, Britta; Zahoransky, Jan; Müller, Stefanie-Katharina; Byrne, James Martin; Schröder, Christian; Behrens, Sebastian; Kappler, Andreas

2015-01-01

Household sand filters are applied to treat arsenic- and iron-containing anoxic groundwater that is used as drinking water in rural areas of North Vietnam. These filters immobilize poisonous arsenic (As) via co-oxidation with Fe(II) and sorption to or co-precipitation with the formed Fe(III) (oxyhydr)oxides. However, information is lacking regarding the effect of the frequency and duration of filter use as well as of filter sand replacement on the residual As concentrations in the filtered water and on the presence of potentially pathogenic bacteria in the filtered and stored water. We therefore scrutinized a household sand filter with respect to As removal efficiency and the presence of fecal indicator bacteria in treated water as a function of filter operation before and after sand replacement. Quantification of As in the filtered water showed that periods of intense daily use followed by periods of non-use and even sand replacement did not significantly (psand replacement, CFUs of Escherichia coli of sand filters regarding As removal, but indicate a potential risk for human health arising from the enrichment of coliform bacteria during filtration and from E. coli cells that are introduced by sand replacement. Copyright © 2014 Elsevier B.V. All rights reserved.

Tratamento de esgoto e produção de água de reúso com o emprego de filtros de areia Wastewater treatment and reuse water production using sand filters

Directory of Open Access Journals (Sweden)

Adriano Luiz Tonetti

2012-09-01

Full Text Available Nesta pesquisa estudou-se um sistema composto pela combinação de filtro anaeróbio com filtro de areia para o tratamento de esgoto. Para isso, foram avaliados três filtros anaeróbios operados com tempo de detenção hidráulica de nove horas, que tinham o efluente disposto sobre quatro filtros de areia em distintas taxas de aplicações. No primeiro filtro de areia aplicaram-se 50 L.m-2 uma vez por dia. No segundo, terceiro e quarto filtros, essa mesma carga foi disposta em dois, três e quatro horários, espaçadas entre às 9:00 e às 16:00 horas. O sistema apresentou um efluente final com qualidade que atendia os padrões para reúso e demanda bioquímica de oxigênio abaixo do limite para o lançamento em corpos hídricos (Decreto de Paulista nº 8.468/1976, indicando a viabilidade de disposição de taxas superiores às sugeridas pela NBR 13969/1997, a qual orienta os aspectos construtivos para esta forma de tratamento.In this research it was studied a system composed by the anaerobic filter combined with a sand filter for the wastewater treatment. For this, three anaerobic filters were operated with hydraulic detention time of nine hours which had the effluent disposed over four sand filters in different frequencies of application. On the first sand filter, 50 L.m-2 were applied once a day. On the second, the third and the fourth filters, the same load was disposed in twice, three and four times a day, distributed between 9 a.m. and 4 p.m. The system presented a final effluent suitable for the COD and BOD legislation maximum limit to be discharged into water body (Decreto Paulista nº 8,468/1976, showing the viability of dispose a higher quantity of effluent then the one suggested by NBR 13969/1997, which guides the constructive aspects for this kind of treatment.

Ecotoxicological studies with newly hatched larvae of Concholepas concholepas (Mollusca, Gastropoda): bioassay with secondary-treated kraft pulp mill effluents.

Science.gov (United States)

Manríquez, Patricio H; Llanos-Rivera, Alejandra; Galaz, Sylvana; Camaño, Andrés

2013-12-01

The Chilean abalone or "loco" (Concholepas concholepas, Bruguière 1789) represent the most economically important marine recourse exploited from inner inshore Management and Exploitation Areas for Benthic Resources along the Chilean coast. In this study, newly-hatched larvae of C. concholepas were investigated as a potential model species for marine ecotoxicological studies. The study developed a behavioral standard protocol for assessing the impact that kraft pulp mill effluents after secondary treatment have on C. concholepas larvae. Under controlled laboratory conditions, newly-hatched larvae were exposed to a series of different concentrations of kraft pulp mill effluents with secondary treatment (Pinus spp. and Eucalyptus spp.), potassium dichromate as standard reference toxicant and effluent-free control conditions. Regardless of the type of effluent the results indicated that diluted kraft pulp effluent with secondary treatment had reduced effect on larval survival. Low larval survivals were only recorded when they were exposed to high concentrations of the reference toxicant. This suggests that C. concholepas larval bioassay is a simple method for monitoring the effects of kraft pulp mill effluents with secondary treatment discharged into the sea. The results indicated that dilution of ca. 1% of the effluent with an elemental chlorine free (ECF) secondary treatment is appropriate for achieving low larval mortalities, such as those obtained under control conditions with filtered seawater, and to minimize their impact on early ontogenetic stages of marine invertebrates such as newly-hatched larvae of C. concholepas. The methodological aspects of toxicological testing and behavioral responses described here with newly-hatched larvae of C. concholepas can be used to evaluate in the future the potential effects of other stressful conditions as other pollutants or changes in seawater pH associated with ocean acidification. © 2013 Elsevier Inc. All rights

Continuous adsorption of Pb(II) and methylene blue by engineered graphite oxide coated sand in fixed-bed column

Energy Technology Data Exchange (ETDEWEB)

Gong, Ji-Lai, E-mail: jilaigong@gmail.com [College of Environmental Science and Engineering, Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha 410082 (China); Zhang, Yong-Liang; Jiang, Yan [College of Environmental Science and Engineering, Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha 410082 (China); Zeng, Guang-Ming, E-mail: zgming@hnu.edu.cn [College of Environmental Science and Engineering, Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha 410082 (China); Cui, Zhi-Hui; Liu, Ke; Deng, Can-Hui; Niu, Qiu-Ya; Deng, Jiu-Hua [College of Environmental Science and Engineering, Key Laboratory of Environmental Biology and Pollution Control, Ministry of Education, Hunan University, Changsha 410082 (China); Huan, Shuang-Yan [State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China)

2015-03-01

Highlights: • GO-sand was prepared by coating GO on the surface of sand. • Pb(II) and MB were efficiently removed by GO-sand filter in column. • The removal of MB was enhanced with the presence of Pb(II). • GO-sand is low-cost and convenient for its application as packed bed filter. - Abstract: The mixture of several effluents, caused by the improper handling and management of effluents, generated multi-component wastewater containing both metals and dyes, leading to the complicated treatment process. In this study, a continuous adsorption of Pb(II) and methylene blue (MB) has been studied in single and binary solutions by using graphite oxide coated sand (GO-sand) as an adsorbent in a fixed-bed column. GO-sand was analyzed by X-ray photoelectron spectroscopy before and after analyte adsorption. Compared with sand filter, adsorption quantity and capacity for Pb(II) and MB by GO-sand filter were greatly increased. In Pb(II) and MB single solutions, the experimental parameters were investigated in detail including initial concentration, flow rate, bed depth and pH. Exhaustion time decreased with increasing initial concentration and flow rate, and increased with increasing bed depth and pH. In the Pb(II)-MB binary solution, exhaustion time significantly decreased for Pb(II) adsorption, but increased for MB adsorption. The reason was explained that the more favorable adsorption for MB onto the surface of GO-sand than that for Pb(II), which was derived from π–π interaction between MB and GO on sand surface in packed filter. The Yoon–Nelson model was applied at different concentration of Pb(II) and MB to predict the breakthrough curves. The experimental data were well fit with the model indicating that it was suitable for this column design.

Removal of heavy metals using a microbial active, continuously operated sand filter

International Nuclear Information System (INIS)

Ebner, C.

2001-01-01

Heavy metals play an important role within the spectrum of the various pollutants, emitted into the environment via human activities. In contrast to most organic pollutants, heavy metal can not be degraded. Many soils, lakes and rivers show a high contamination with heavy metals due to the enrichment of these pollutants. In addition to existing chemical-physical and biological technologies for the treatment of heavy metal containing waste waters a demand for new, efficient and low-cost cleaning technologies exists, particularly for high volumes of weakly contaminated waters. Such a technology was developed within the framework of a scientific project of the European Union. The approach makes use of a continuously operated, moving-bed Astrasand filter, which has been operated as a continuous biofilm reactor. By inoculation of the reactor with bacteria providing different, defined mechanisms of metal immobilization, and by continuous supply of suitable nutrients, a metal-immobilizing biofilm is built up and regenerated continuously. Metal-enriched biomass is removed continuously from the system, and the contained metals can be recycled by pyrometallurgical treatment of the biomass. The subjects of the present work were the optimization of the nutrient supply for the process of metal removal, the investigation of the toxicity of different waste waters, the optimization of inoculation and biofilm formation, set-up and operation of a lab scale sand filter and the operation of a pilot scale sand filter treating rinsing water of a chemical nickel plating plant. First, basic parameters like toxicity of heavy metal-containing waste waters and the influence of the nutrition of bacteria on biosorption and total metal removal were examined, using freely suspended bacteria in batch culture. Concerning toxicity great differences could be found within the spectrum of heavy metal-containing waste waters tested. Some waters completely inhibited growth, while others did not

Discovery and description of complete ammonium oxidizers in groundwater-fed rapid sand filters

DEFF Research Database (Denmark)

Palomo, Alejandro

as biological filtration has long been acknowledged and recently been investigated. Biological filtration technology is widely used around the world and is especially important in Denmark as groundwater is the main source water for drinking water production. Because the groundwater has a relative high-quality......, aeration followed by biological filtration is the only required treatment before distribution. In the last years, the microbial communities in rapid gravity sand filters, the typical biological filter used in Denmark, have been characterized, but little knowledge had been required about their physiological...... activity and roles in compound removal from the source water. This PhD project focused on a comprehensive investigation of the microbial communities in rapid sand filters beyond their purely taxonomical identification. For this purpose, samples collected from a rapid sand filter were subjected...

Performance of sand filters for the separations areas at the Savannah River Laboratory

International Nuclear Information System (INIS)

Orth, D.A.; Sykes, G.H.; McKibben, J.M.

1981-01-01

Two new large sand filters, 30.5 by 100 m, were constructed and put into service at the Savannah River Plant (SRP) in 1975 and 1976. These units were designed to provide final filtration of process air - one for each of the two separations areas. Eventual flow will be 4950 m 3 /min (205,000 scfm) on each unit when all facilities are connected. They were built as replacements for the original sand filters that began operation in 1954 and 1955. The new filters have been operated in parallel with the old units following partial failure of the old units from acid attack and erosion of the concrete support structure for the sand beds. The design of the new units was based on extensive tests at SRP on characteristics of different sands. The performance of the new filters meets criteria for pressure drop, flow capacity, and efficiency. The efficiencies measured by DOP test are greater than 99.98%. Parallel operation reduces air velocity through the beds, which increases efficiency. A characteristic of sand filter performance has been low apparent efficiency at low input; efficiency increases as the activity input rises. This is attributed to a small entrainment release from the large amount of activity already sorbed on the filter; this release controls and lowers the calculated efficiency at low input. An analysis of efficiency as a function of input activity projects efficiencies greater than 99.99% for large inputs that might be characteristic of large internal accidents. The data indicate that DOP efficiencies can be used in hazards analyses to determine accident consequences. Routine evaluation of filter releases can be used for surveillance to establish that performance is normal at other times

Hydrodynamic calculation of a filter sand bed type used in the containment venting systems

International Nuclear Information System (INIS)

Cuevas V, D.; Sainz M, E.; Ortiz V, J.

2015-09-01

The filtered venting of the containment has been adopted in European countries to mitigate the consequences of excess pressure containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter on the same path is placed, so that various types of filters are used to trap the fission products. The venting filters of the containment currently installed use different filtration technologies that involve more than one medium. Those using water as the first stage of filtration are called wet systems and are equipped with additional steps to remove water drops and fine aerosols emissions. And even they may also be equipped with an element containing certain absorption means for the filtration of gaseous iodine species. Other designs based on filtration of deep bed as the primary retention step; called dry filters, use filtration media of metal fiber, ceramic or sand to trap aerosols. This paper evaluates the hydraulic characteristics of the filter sand bed type designed by EDF as a candidate to be installed in the containment of BWR Mark II (type of primary containment of the nuclear power plant of Laguna Verde). The evaluation of filter sand bed type was performed using the software package of open source OpenFOAM. Models of each zone of the filtered device were generated and through a series of parametric calculations of computational fluid mechanics relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow rate and pressure fields and speed at different operating conditions. On the other hand, the model validation of the sand bed filter when comparing the results of experimental tests on a sand column of PITEAS program (1985-1986) against OpenFOAM simulation was realized. The results are very close to those obtained experimentally. (Author)

Assessment of contamination by percolation of septic tank effluent through natural and amended soils.

Science.gov (United States)

Cheung, K C; Venkitachalam, T H

2004-01-01

Fly ash has been found to be a potential material for the treatment of municipal and industrial wastewater, and may be useful in the treatment of septic tank effluent. Laboratory columns (30 cm) were used to determine the sorption capacity and hydraulic properties of lagoon fly ash, loamy sand, sand, and sand amended by lagoon fly ash (30 and 60%) and red mud gypsum (20%). The removal of chemical oxygen demand (COD) was high in all column effluents (71-93%). Extent of nitrification was high in Spearwood sand, Merribrook loamy sand and 20% red mud gypsum amended Spearwood sand. However, actual removal of nitrogen (N) was high in columns containing lagoon fly ash. Unamended Spearwood sand possessed only minimal capacity for P sorption. Merribrook loamy sand and red mud gypsum amended sand affected complete P removal throughout the study period of 12 weeks. Significant P leakage occurred from lagoon fly ash amended sand columns following 6-10 weeks of operation. Neither lagoon fly ash nor red mud gypsum caused any studied heavy metal contamination including manganese (Mn), lead (Pb), zinc (Zn), cadmium (Cd) and chromium (Cr) of effluent. It can be concluded that Merribrook loamy sand is better natural soil than Spearwood sand as a filter medium. The addition of lagoon fly ash enhanced the removal of P in Spearwood sand but the efficiency was lower than with red mud gypsum amendment.

Human norovirus in untreated sewage and effluents from primary, secondary and tertiary treatment processes.

Science.gov (United States)

Campos, Carlos J A; Avant, Justin; Lowther, James; Till, Dale; Lees, David N

2016-10-15

Wastewater treatments are considered important means to control the environmental transmission of human norovirus (NoV). Information about NoV concentrations in untreated and treated effluents, their seasonality and typical removal rates achieved by different treatment processes is required to assess the effectiveness of sewage treatment processes in reducing human exposure to NoV. This paper reports on a characterisation of concentrations of NoV (genogroups I and II) in untreated sewage (screened influent) and treated effluents from five full scale wastewater treatment works (WwTW) in England. Results are shown for effluent samples characteristic of primary- (primary settlement, storm tank overflows), secondary- (activated sludge, trickling filters, humus tanks) and tertiary (UV disinfection) treatments. NoV occurrence in untreated sewage varied between years. This variation was consistent with the annual variation of the virus in the community as indicated by outbreak laboratory reports. Significant differences were found between mean NoV concentrations in effluents subject to different levels of treatment. Primary settlement achieved approximately 1 log10 removal for both genogroups. Concentrations of NoV and Escherichia coli in untreated sewage were of the same order of magnitude of those in storm tank overflows. Of the secondary treatments studied, activated sludge was the most effective in removing NoV with mean log10 removals of 3.11 and 2.34 for GI and GII, respectively. The results of this study provide evidence that monitoring of NoV in raw sewage or treated effluents could provide early warning of an elevated risk for NoV and potentially help prevent outbreaks through environmental exposure. They also provide evidence that elimination of stormwater discharges and improvement of the efficiency of activated sludge for NoV removal would be effective for reducing the risk of environmental transmission. Crown Copyright © 2016. Published by Elsevier Ltd. All

Numerical modelling of the erosion and deposition of sand inside a filter layer

DEFF Research Database (Denmark)

Jacobsen, Niels Gjøl; van Gent, Marcel R. A.; Fredsøe, Jørgen

2017-01-01

This paper treats the numerical modelling of the behaviour of a sand core covered by rocks and exposed to waves. The associated displacement of the rock is also studied. A design that allows for erosion and deposition of the sand core beneath a rock layer in a coastal structure requires an accurate...... prediction method to assure that the amount of erosion remains within acceptable limits. This work presents a numerical model that is capable of describing the erosion and deposition patterns inside of an open filter of rock on top of sand. The hydraulic loading is that of incident irregular waves...... and the open filters are surface piercing. Due to the few experimental data sets on sediment transport inside of rock layers, a sediment transport formulation has been proposed based on a matching between the numerical model and experimental data on the profile deformation inside an open filter. The rock layer...

Nano sand filter with functionalized nanoparticles embedded in anodic aluminum oxide templates

Science.gov (United States)

Phuong, Nguyenthi; Andisetiawan, Anugrah; van Lam, Do; Kim, Jeong Hwan; Choi, Doo-Sun; Whang, Kyung-Hyun; Nham, Jeasun; Lee, Yun Jung; Yoo, Yeong-Eun; Yoon, Jae Sung

2016-11-01

Since the ancient Egyptians had used sand as filter media for water purification, its principle has been inherited through generations and it is still being used now in industries. The sand filter consists of sand literally, and the voids within the sand bed are the pores for filtration. Here we present a filtration principle using nanoparticles, so that the voids between the nanoparticles can be considered as effective pores in nanoscale dimension. Anodic aluminum oxide (AAO) membrane has been used as the working template, and the nanoparticles have been injected and embedded within the pores of the AAO template. Nanoparticles with multiple sizes have been used in order to obtain smaller voids. Moreover, the nanoparticles have been functionalized, or electrically charged, with arginine/phenylalanine (RF) peptide group. In this way, filtration performance for charged particles or molecules, such as methylene blue, has been enhanced. Consequently, this study is expected to provide a new principle for fabrication of nano voids, or nano pores, and for filtration in nanoscale dimension.

Drawer compacted sand filter: a new and innovative method for on-site grey water treatment.

Science.gov (United States)

Assayed, Almoayied; Chenoweth, Jonathan; Pedley, Steven

2014-01-01

In this paper, results ofa new sand filter design were presented. The drawer compacted sand filter (DCSF) is a modified design for a sand filter in which the sand layer is broken down into several layers, each of which is 10 cm high and placed in a movable drawer separated by a 10 cm space. A lab-scale DCSF was designed and operated for 330 days fed by synthetic grey water. The response of drawer sand filters to variable hydraulic and organic loading rates (HLR and OLR) in terms of biological oxygen demand (BODs), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity and Escherichia coli reductions were evaluated. The HLR was studied by increasing from 72 to 142 L m(-2) day(-1) and OLR was studied by increasing it from 23 to 30 g BOD5 m(-2) day(-1) while keeping the HLR constant at 142 L m(-2) day(-1). Each loading regime was applied for 110 days. Results showed that DCSF was able to remove >90% of organic matter and total suspended solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P water was drained through the third drawer in all tested loads. The paper concludes that DCSF would be appropriate for use in dense urban areas as its footprint is small and is appropriate for a wide range of users because of its convenience and low maintenance requirements.

Performance of a sand filter in removal of micro-algae from seawater in aquaculture production systems.

Science.gov (United States)

Sabiri, N E; Castaing, J B; Massé, A; Jaouen, P

2012-01-01

In this study, a sand filter was used to remove micro-algae from seawater feeding aquaculture ponds. A lab-scale sand filter was used to filter 30,000 cells/mL of Heterocapsa triquetra suspension, a non-toxic micro-alga that has morphological and dimensional (15-20 microm) similarities with Alexandrium sp., one of the smallest toxic micro-algae in seawater. Removal efficiency and capture mechanisms for a fixed superficial velocity (3.5 m/h) were evaluated in relation to size distribution and mean diameter of the sand. Various sands (average diameter ranging between 200 microm and 600 microm) were characterized and used as porous media. The structural parameters of the fixed beds were evaluated for each medium using experimental measurements of pressure drop as a function of superficial velocity over a range of Reynolds numbers covering Darcy's regime and the inertial regime. For a filtration cycle of six hours, the best efficiency (E = 90%) was obtained with the following sand characteristics: sieved sand with a range of grain diameter of 100 and 300 microm and a mean grain diameter equal to 256 microm. Results obtained show the influence of the size distribution of sand on the quality of retention of the micro-algae studied.

Microbial degradation of pesticides in rapid sand filters used for drinking water treatment

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen

significantly with the maximum methane concentration in the raw water and did not correlate with other water quality parameters, such as the ammonium concentration. Furthermore, the connection between bentazone degradation and methane oxidation in filter sand was demonstrated by inhibition experiments, in which...... sustainable methods to remove pesticides from polluted water sources. Aeration of anaerobic groundwater, followed by biological rapid sand filtration is a widespread technology in drinking water treatment. Even though these systems are not designed for removal of trace contaminants, they have shown potential...... for microbial degradation of pesticides and their degradation products. If pesticides can be removed in rapid sand filters, it is of large commercial interest due to the importance in maintaining a simple, sustainable water treatment. To take advantage of the microbial pesticide degradation and identify...

Efficacy of HRF in COD Removal from Secondary Effluent of Yasuj Municipal Wastewater

Directory of Open Access Journals (Sweden)

M Ehteshami

2011-10-01

Full Text Available Background & Aim: Re-use of wastewater is an appropriate approach for development of water resources and water supply strategies. The purpose of this study was to determine the efficacy of HRF in COD removal from secondary effluent of municipal wastewater in Yasouj. Methods: The pilot which was used in the present study was a horizontal roughing filter designed and prepared according to the Wegelin’s Design Criteria. The Samples were removed daily and instantaneous based on the predicted number of samples (28 samples at each filtration rate from the input and output filter, and then tested in the laboratory by the D5000 device. The collected data was analyzed using ANOVA and paired t-test. Results: The results indicated that the average COD removal in the filtration rate of 0.5, 1, and 1.5 were 60, 51, and 38 percent respectively. Conclusion: The average output of the HRF for all three filtration rates was lower than the maximum EPA standard of Iran.

Technical review of WSRC-TR-93-614 criticality safety evaluation for disassembly basin sand filter

International Nuclear Information System (INIS)

Reed, R.L.

1994-01-01

The study documented in WSRC-TR-93-614 performed an evaluation of the criticality potential associated with the Disassembly Basin Sand Filter for K and L Areas. The document reviewed incorporated results of calculations documented in the engineering calculation N-CLC-K-00151. Analyses of the contents of disassembly basin sludge has indicated that the sludge contains fissile material in excess of subcritical mass limits as specified in ANSI/ANS standards. Previous studies had determined that the fissile material can not collect into a critical configuration in the basin. Since the sand filter is intended to remove suspended particles from the basin water and could serve as a mechanism to collect the fissile material into a critical configuration, the study examined conditions under which criticality could occur in the sand filter. The study shows that criticality is not considered possible in the sand filter. This review emphasized the technical accuracy and presentation of the evaluation. The evaluation was also examined for the elements required for NCSEs. The review was performed in accordance with the NRTSC technical review requirements and procedures and the E7 Manual technical review requirements. The technical review (per the E7 manual) of the engineering calculation (N-CLC-K-0 1 5 1) was previously performed by this reviewer

Experimental research on accelerated consolidation using filter jackets in fine oil sands tailings

Energy Technology Data Exchange (ETDEWEB)

Tol van, F.; Yao, Y.; Paaseen van, L.; Everts, B. [Delft Univ. of Technology, Delft (Netherlands). Dept. of Geotechnology

2010-07-01

This PowerPoint presentation discussed prefabricated vertical drains used to enhance the dewatering of fine oil sand tailings. Filtration tests conducted with thickened tailings on standard PVD jackets were presented. Potential clogging mechanisms included clogging of the filter jacket by particles, blinding of the jackets by filter cake, the decreased permeability of consolidated tailings around the drain, and the clogging of the filter jacket with bitumen. Polypropylene and polyester geotextiles were tested in a set-up that replicated conditions observed at 5 to 10 meters below mud level in an oil sand tailings pond. A finite strain consolidation model was used to interpret results obtained in the experimental study. The relationship between the void ratio and hydraulic conductivity was investigated. Results of the study showed that neither the bitumen nor the fines in the sludge cause serious blinding of the filter jackets during the 40 day test period. The consolidation process was adequately simulated with the finite strain consolidation model. tabs., figs.

Treatment option evaluation for liquid effluent secondary streams on the Hanford Site

International Nuclear Information System (INIS)

Holter, G.M.; Triplett, M.B.; Fow, C.L.; White, M.K.

1988-08-01

This study, conducted by the Pacific Northwest Laboratory (PNL) for Westinghouse Hanford Company (WHC), examines the range of secondary waste types and volumes likely to result from treatment of contaminated liquid effluents. Alternatives for treatment of these effluents were considered, taking into account the implementation of the ''best-available technology'' as assumed in current and ongoing engineering studies for treating the various liquid effluent waste streams. These treatment alternatives, and potential variations in the operating schedules for Hanford Site facilities generating contaminated liquid effluents, were evaluated to project an estimated range for the volume of each of the various secondary waste streams that are likely to be generated. The conclusions and recommendations were developed, based on these estimates. 23 refs., 34 figs., 16 tabs

Analysis of the implementation of a sand bed type filter for the venting of a nuclear power plant

International Nuclear Information System (INIS)

Cuevas V, D.; Sainz M, E.; Ortiz V, J.

2017-09-01

The filtered venting of the containment has been adopted in European countries to mitigate the consequences derived from the excess pressure of the containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter is placed in the path of the same, so various types of filters are used to trap the fission products. The containment venting filters currently installed use different filtering technologies that involve more than one medium. Those who use water as the first stage of filtration are called wet systems, are equipped with additional stages to eliminate water drops and emissions of fine aerosols, and may even be equipped with an element that contains certain means of absorption for the gaseous iodine species filtration. Other designs, based on deep bed filtration as the main retention stage, called dry filters; use metal fiber, ceramic or sand filtration media to trap aerosols. The present work evaluates the hydraulic characteristics of the sand bed type filter designed by EDF as a candidate to be installed in the containment of the BWR Mark II (primary containment type of the Laguna Verde nuclear power plant). The evaluation of the sand bed filter was performed using the OpenFOAM open source software package. Models of each zone of the filtering device were generated and by means of a series of parametric calculations of computational fluid mechanics, the relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow and pressure fields and velocity under different operating conditions. On the other hand, the validation of the sand bed filter model was made when comparing the results of experimental tests carried out in a sand column of the PITEAS program (1985-1986) against the simulation in OpenFOAM. The results obtained are very close to those obtained experimentally. (Author)

Nickel removal from nickel plating waste water using a biologically active moving-bed sand filter.

Science.gov (United States)

Pümpel, Thomas; Macaskie, Lynne E; Finlay, John A; Diels, Ludo; Tsezos, Marios

2003-12-01

Efficient removal of dissolved nickel was observed in a biologically active moving-bed 'MERESAFIN' sand filter treating rinsing water from an electroless nickel plating plant. Although nickel is fully soluble in this waste water, its passage through the sand filter promoted rapid removal of approximately 1 mg Ni/l. The speciation of Ni in the waste water was modelled; the most probable precipitates forming under the conditions in the filter were predicted using PHREEQC. Analyses of the Ni-containing biosludge using chemical, electron microscopical and X-ray spectroscopic techniques confirmed crystallisation of nickel phosphate as arupite (Ni3(PO4)2 x 8H2O), together with hydroxyapatite within the bacterial biofilm on the filter sand grains. Biosorption contributed less than 1% of the overall sequestered nickel. Metabolising bacteria are essential for the process; the definitive role of specific components of the mixed population is undefined but the increase in pH promoted by metabolic activity of some microbial components is likely to promote nickel desolubilisation by others.

Efficiency Evaluation of Filtration with Fluidized Bed for Treatment of Secondary Effluents for Reuse

OpenAIRE

Mohammad Hosaini; Rohallah Moradi; Gholam Hossain Safari

2013-01-01

Background & Objectives: Recently, deficient in atmospheric drop and discharges of wastewater effluents leads to serious threat for water resource. For that reason, for prevention of water source pollution and also reuse of wastewater effluents, treatment of such effluents seems to be necessary. Methods: In this work, fluidized bed reactor with a filter was used for treatment of effluents from Shahrak Gharb wastewater treatment plant. Various parameters such as BOD5, COD, TS, TP, TN and t...

Heterogeneity of Rapid Sand Filters and Its Effect on Contaminant Transport and Nitrification Performance

DEFF Research Database (Denmark)

Lopato, Laure Rose; Galaj, Zofia; Delpont, Sébastien

2011-01-01

Laboratory and full-scale experiments were conducted to investigate the development and effect of heterogeneity caused by filter media nonuniformity, biofilm, particles, precipitates, and gas bubbles in rapid sand filters used for drinking-water treatment. Salt tracer experiments were conducted...

Interactions between microbial activity and distribution and mineral coatings on sand grains from rapid sand filters treating groundwater

DEFF Research Database (Denmark)

Gülay, Arda; Tatari, Karolina; Musovic, Sanin

Rapid sand filtration is a traditional and widespread technology for drinking water purification which combines biological, chemical and physical processes together. Granular media, especially sand, is a common filter material that allows several oxidized compounds to accumulate on its surface....... Preliminarily, we detected a strong relation between the amount of DNA and mineral coating mass. We hypothesized that the accumulated mineral coatings have a positive effect on amount of bacterial biomass, its spatial distribution and substrate removal rates. In this study, we combined molecular, microscopic...

Sodium fire aerosol loading capacity of several sand and gravel filters

International Nuclear Information System (INIS)

Barreca, J.R.; McCormack, J.D.

1980-04-01

Improved specific loading capacity for sodium fire aerosols was the objective of a sand and gravel test series. The aerosol capacity and related differential pressure of eight aggregate filters is presented. A maximum specific aerosol capacity, for dry aerosol, of 2.4 kg (Na) m -2 was obtained. This filter was loaded to a final differential pressure of 2.6 kPa. The average superficial face velocity was 0.5 cm/s and the average efficiency was 99.8%. The test results indicate that filter capacity increases with aerosol moisture content and with decreasing superficial velocity

Nutrient loading on subsoils from on-site wastewater effluent, comparing septic tank and secondary treatment systems.

Science.gov (United States)

Gill, L W; O'Luanaigh, N; Johnston, P M; Misstear, B D R; O'Suilleabhain, C

2009-06-01

The performance of six separate percolation areas was intensively monitored to ascertain the attenuation effects of unsaturated subsoils with respect to on-site wastewater effluent: three sites receiving septic tank effluent, the other three sites receiving secondary treated effluent. The development of a biomat across the percolation areas receiving secondary treated effluent was restricted on these sites compared to those sites receiving septic tank effluent and this created significant differences in terms of the potential nitrogen loading to groundwater. The average nitrogen loading per capita at 1.0m depth of unsaturated subsoil equated to 3.9 g total-N/d for the sites receiving secondary treated effluent, compared to 2.1 g total-N/d for the sites receiving septic tank effluent. Relatively high nitrogen loading was, however, found on the septic tank sites discharging effluent into highly permeable subsoil that counteracted any significant denitrification. Phosphorus removal was generally very good on all of the sites although a clear relationship to the soil mineralogy was determined.

Application of a Low Cost Ceramic Filter for Recycling Sand Filter Backwash Water

Directory of Open Access Journals (Sweden)

Md Shafiquzzaman

2018-02-01

Full Text Available The aim of this study is to examine the application of a low cost ceramic filter for the treatment of sand filter backwash water (SFBW. The treatment process is comprised of pre-coagulation of SFBW with aluminum sulfate (Alum followed by continuous filtration usinga low cost ceramic filter at different trans-membrane pressures (TMPs. Jar test results showed that 20 mg/L of alum is the optimum dose for maximum removal of turbidity, Fe, and Mn from SFBW. The filter can be operated at a TMP between 0.6 and 3 kPa as well as a corresponding flux of 480–2000 L/m2/d without any flux declination. Significant removal, up to 99%, was observed forturbidity, iron (Fe, and manganese (Mn. The flux started to decline at 4.5 kPa TMP (corresponding flux 3280 L/m2/d, thus indicated fouling of the filter. The complete pore blocking model was found as the most appropriate model to explain the insight mechanism of flux decline. The optimum operating pressure and the permeate flux were found to be 3 kPa and 2000 L/m2/d, respectively. Treated SFBW by a low cost ceramic filter was found to be suitable to recycle back to the water treatment plant. The ceramic filtration process would be a low cost and efficient option to recycle the SFBW.

Gamma irradiation treatment of secondary sewage effluent

International Nuclear Information System (INIS)

Vajdic, A.H.

The operation and monitoring of a pilot scale Co-60 gamma irradiation unit treating secondary sewage effluent is described. The disinfecting efficiency of the unit is compared to that of an experimental 'ideal' chlorination unit and to the plant chlorination process. A cost estimate for disinfection by gamma irradiation on a full plant scale is included. (author)

Conversion of sand filters into activated carbon filters at the La Presa (Valencia) water works; Conversion de filtros de arena porcarbon activo en la ETAP de La Presa (Valencia)

Energy Technology Data Exchange (ETDEWEB)

Macian Cervera, V. J.; Monforte Monleon, L.; Ribera Orts, R.; Suris Jorda, J. I.; Klee, J. M.

2007-07-01

To improve the water quality at potable water treatment plant of La P esa (Valencia), the sand filters have been replaced for activated carbon filters. In the following review the results and conclusions of the direct sand filter conversion into activated carbon filters will be presented. The leads to a simple and fast solution to odour and taste removal, as well as dissolved organic matter, without investments in works at the water works. (Author)

Importance of copper for nitrification in biological rapid sand filters for drinking water production

DEFF Research Database (Denmark)

Wagner, Florian Benedikt

When anoxic groundwater is treated to produce drinking water, ammonium is commonly removed through nitrification in rapid sand filters. Nitrification is a biological process, and is mediated by chemoautotrophic microorganisms. Ammonia oxidizing bacteria (AOB) and archaea (AOA) oxidize ammonium...... to remove ammonium to below the national drinking water quality standard of 0.05 mg NH4+/L. A better process understanding of nitrifying biofilters is needed to optimize treatment performance, remediate existing filters, and to prevent future nitrification problems. The frequent incidents of insufficient...... in the oxidation of ammonia to hydroxylamine. Thus, slow and incomplete nitrification could be caused by a lack of sufficient amounts of copper. The overall aim of this PhD project was therefore to determine whether copper supplementation could enhance nitrification in rapid sand filters with incomplete...

Enhanced performance of a submerged membrane bioreactor with powdered activated carbon addition for municipal secondary effluent treatment

Energy Technology Data Exchange (ETDEWEB)

Lin, Hongjun, E-mail: hjlin@zjnu.cn [College of Geography and Environmental Sciences, Zhejiang Normal University, 688 Yingbin Avenue, Jinhua, Zhejiang Province 321004 (China); Wang, Fangyuan; Ding, Linxian; Hong, Huachang [College of Geography and Environmental Sciences, Zhejiang Normal University, 688 Yingbin Avenue, Jinhua, Zhejiang Province 321004 (China); Chen, Jianrong, E-mail: cjr@zjnu.cn [College of Geography and Environmental Sciences, Zhejiang Normal University, 688 Yingbin Avenue, Jinhua, Zhejiang Province 321004 (China); Lu, Xiaofeng [Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201800 (China)

2011-09-15

Highlights: {yields} The first study to investigate the feasibility of PAC-MBR process treating municipal secondary effluent. {yields} The study revealed that most organics in the secondary effluent were low molecular weight (MW) substances, which could be retained in the reactor and then removed to some extent by PAC-MBR process. {yields} The study suggested that the action of biomass and the PAC is mutual and synergistic. - Abstract: The aim of this study was to investigate the feasibility of PAC-MBR process treating municipal secondary effluent. Two laboratory-scale submerged MBRs (SMBR) with and without PAC addition were continuously operated in parallel for secondary effluent treatment. Approximately 63%TOC, 95% NH{sub 4}{sup +}-N and 98% turbidity in secondary effluent were removed by the PAC-MBR process. Most organics in the secondary effluent were found to be low molecular weight (MW) substances, which could be retained in the reactor and then removed to some extent by using PAC-MBR process. Parallel experiments showed that the addition of PAC significantly increased organic removal and responsible for the largest fraction of organic removal. Membrane fouling analysis showed the enhanced membrane performance in terms of sustainable operational time and filtration resistances by PAC addition. Based on these results, the PAC-MBR process was considered as an attractive option for the reduction of pollutants in secondary effluent.

Enhanced performance of a submerged membrane bioreactor with powdered activated carbon addition for municipal secondary effluent treatment

International Nuclear Information System (INIS)

Lin, Hongjun; Wang, Fangyuan; Ding, Linxian; Hong, Huachang; Chen, Jianrong; Lu, Xiaofeng

2011-01-01

Highlights: → The first study to investigate the feasibility of PAC-MBR process treating municipal secondary effluent. → The study revealed that most organics in the secondary effluent were low molecular weight (MW) substances, which could be retained in the reactor and then removed to some extent by PAC-MBR process. → The study suggested that the action of biomass and the PAC is mutual and synergistic. - Abstract: The aim of this study was to investigate the feasibility of PAC-MBR process treating municipal secondary effluent. Two laboratory-scale submerged MBRs (SMBR) with and without PAC addition were continuously operated in parallel for secondary effluent treatment. Approximately 63%TOC, 95% NH 4 + -N and 98% turbidity in secondary effluent were removed by the PAC-MBR process. Most organics in the secondary effluent were found to be low molecular weight (MW) substances, which could be retained in the reactor and then removed to some extent by using PAC-MBR process. Parallel experiments showed that the addition of PAC significantly increased organic removal and responsible for the largest fraction of organic removal. Membrane fouling analysis showed the enhanced membrane performance in terms of sustainable operational time and filtration resistances by PAC addition. Based on these results, the PAC-MBR process was considered as an attractive option for the reduction of pollutants in secondary effluent.

Comammox Nitrospira are abundant ammonia oxidizers in diverse groundwater‐fed rapid sand filter communities

DEFF Research Database (Denmark)

Fowler, Susan Jane; Palomo, Alejandro; Dechesne, Arnaud

2018-01-01

quantification and diversity assessement of both comammox Nitrospira clades. The primers cover a wide range of comammox diversity, spanning all available high quality sequences. We applied these primers to 12 groundwater‐fed rapid sand filters, and found comammox Nitrospira to be abundant in all filters. Clade B...

Characterization of secondary treated effluents for tertiary membrane filtration and water recycling

KAUST Repository

Ayache, C.; Pidou, Marc; Gernjak, Wolfgang; Poussade, Yvan; Croue, Jean-Philippe; Tazi-Pain, Annie; Keller, Jurg R.

2012-01-01

This study evaluates the impacts of water quality from three different secondary effluents on low pressure membrane fouling. Effluent organic matter (EfOM) has been reported by previous studies as responsible for membrane fouling. However, the contribution of the different components of EfOM to membrane fouling is still not well understood. In order to improve and optimize treatment processes, characterization and quantification of the organic matter are important. The characterization methods used in this study are liquid chromatography coupled with an organic detector (LC-OCD) and excitation emission matrix fluorescence spectroscopy (EEM). A bench-scale hollow fibre membrane system was used to identify the type of fouling depending on the feed water quality. Results showed no measurable dissolved organic carbon removal by the membranes for the three secondary effluents. Biopolymers and humic-like substances found in different proportions in the three effluents were partially retained by the membranes and were identified to contribute significantly to the flux decline of the low pressure membranes. The observed fouling was determined to be reversible by hydraulic backwashing for two effluents and only by chemical cleaning for the third effluent. © IWA Publishing 2012.

Characterization of secondary treated effluents for tertiary membrane filtration and water recycling

KAUST Repository

Ayache, C.

2012-06-01

This study evaluates the impacts of water quality from three different secondary effluents on low pressure membrane fouling. Effluent organic matter (EfOM) has been reported by previous studies as responsible for membrane fouling. However, the contribution of the different components of EfOM to membrane fouling is still not well understood. In order to improve and optimize treatment processes, characterization and quantification of the organic matter are important. The characterization methods used in this study are liquid chromatography coupled with an organic detector (LC-OCD) and excitation emission matrix fluorescence spectroscopy (EEM). A bench-scale hollow fibre membrane system was used to identify the type of fouling depending on the feed water quality. Results showed no measurable dissolved organic carbon removal by the membranes for the three secondary effluents. Biopolymers and humic-like substances found in different proportions in the three effluents were partially retained by the membranes and were identified to contribute significantly to the flux decline of the low pressure membranes. The observed fouling was determined to be reversible by hydraulic backwashing for two effluents and only by chemical cleaning for the third effluent. © IWA Publishing 2012.

Mechanical properties of chemically bonded sand core materials dipped in sol-gel coating impregnated with filter

DEFF Research Database (Denmark)

Nwaogu, Ugochukwu Chibuzoh; Tiedje, Niels Skat

2012-01-01

A novel sol-gel coating impregnated with filter dust was applied on chemically bonded sand core materials by dipping. After curing, the strengths of the core materials were measured under uniaxial loading using a new strength testing machine (STM). The STM presents the loading history as a force-...... of the chemically bonded sand core materials, a combination of flexural and compression tests is suggested for improving the casting quality. © 2012 W. S. Maney & Son Ltd.......A novel sol-gel coating impregnated with filter dust was applied on chemically bonded sand core materials by dipping. After curing, the strengths of the core materials were measured under uniaxial loading using a new strength testing machine (STM). The STM presents the loading history as a force...... the strengths were increased under compression. The mode of fracture of the chemically bonded sand core materials was observed to be intergranular through the binder. The stiffness of the chemically bonded sand core materials was determined. For better understanding of the mechanical properties...

Reuse of wastewater effluents in Saudi Arabia

International Nuclear Information System (INIS)

Ishaq, A.M.; Al-Suwaiyan, M.S.

2002-01-01

In the initial phase of a six-year study, laboratory investigations were carried out to establish conservative estimates of the contaminant removals that are possible by the recharge of local secondary effluents through a sand dune. In the preliminary laboratory study, chlorinated effluent was found to be more suitable than unchlorinated wastewater with respect to the development of anaerobic conditions and headlosses. In the main laboratory study, a 5-m high Plexiglass sand box column was used to investigate conservative predictions for the removal of contaminants. The average removals of BOD, COD, and TOC were over 65%, 65%, and 55%, respectively. The COD was primarily removed in the first 200 cm of the column. The effluent had a residual TOC of 1.66 mg/l and consisted of humic substances. The average removal of microbial indicator organisms: Total Coliform (TC) and Coliphage were over 85% and 66%, respectively. The product water contained only nominal amounts of TC (Average - 21.5 MPN/100 ml) and Coliphage (Average - 6 PFU/100 ml). The porous media largely remained unaffected by the recharge operation. In the second phase, a 'field recharge system' was constructed and recharge operations were carried out over a two year period resulting in the following observations. a. The quality of the end product will depend entirely on the quality of the secondary effluent. b. With the soil aquifer treatment system (SATS) under consideration, it was possible to achieve product water meeting the recharge standards with respect to heavy metals, pH, BOD, TOC, fecal coliform and total coliform. c. The product water met the standards for restricted and unrestricted irrigation. (author)

Reuse of wastewater effluents in Saudi Arabia

Energy Technology Data Exchange (ETDEWEB)

Ishaq, A.M.; Al-Suwaiyan, M.S. [King Fahd Univ. of Petroleum and Minerals, Dept. of Civil Engineering, Dhahran (Saudi Arabia)

2002-06-15

In the initial phase of a six-year study, laboratory investigations were carried out to establish conservative estimates of the contaminant removals that are possible by the recharge of local secondary effluents through a sand dune. In the preliminary laboratory study, chlorinated effluent was found to be more suitable than unchlorinated wastewater with respect to the development of anaerobic conditions and headlosses. In the main laboratory study, a 5-m high Plexiglass sand box column was used to investigate conservative predictions for the removal of contaminants. The average removals of BOD, COD, and TOC were over 65%, 65%, and 55%, respectively. The COD was primarily removed in the first 200 cm of the column. The effluent had a residual TOC of 1.66 mg/l and consisted of humic substances. The average removal of microbial indicator organisms: Total Coliform (TC) and Coliphage were over 85% and 66%, respectively. The product water contained only nominal amounts of TC (Average - 21.5 MPN/100 ml) and Coliphage (Average - 6 PFU/100 ml). The porous media largely remained unaffected by the recharge operation. In the second phase, a 'field recharge system' was constructed and recharge operations were carried out over a two year period resulting in the following observations. a. The quality of the end product will depend entirely on the quality of the secondary effluent. b. With the soil aquifer treatment system (SATS) under consideration, it was possible to achieve product water meeting the recharge standards with respect to heavy metals, pH, BOD, TOC, fecal coliform and total coliform. c. The product water met the standards for restricted and unrestricted irrigation. (author)

Assessment of crushed-recycled glass as filter media for drinking water treatment

International Nuclear Information System (INIS)

Rutledge, S.O.; Fahie, C.; Gagnon, G.A.

2002-01-01

The objective of this project was to evaluate the performance of a pressure filter utilizing crushed glass as the filter media. The performance of the crushed glass filter was compared to that of a sand filter. The research was conducted in Orangedale, Nova Scotia, which is a small community of with a population of approximately 500. Orangedale is located on the south shore of Bras d'Or Lakes and feeds into Miller Pond, which serves as the source the of drinking water. The Orangedale treatment plant produces an average daily flow of 35 m3/d (6.4-gpm). The treatment plant consists of coagulation (sodium aluminate and polyaluminum chloride), flocculation, dissolved air flotation (DAF), disinfection with sodium hypochlorite and dual-media filtration with anthracite and sand. In general, the particle removal capabilities of the crushed glass filter were slightly poorer than that of a sand filter, as quantified in a field application in the community of Orangedale, Nova Scotia. It was found that the crushed glass used in this project had a higher angularity and slightly higher uniformity coefficient. During initial start-up the performance of the crushed glass filter was more variable and appeared to improve as the glass began to wear. After six-months of use the crushed glass filter was able to produce a very consistent filter effluent that was only slightly greater than the silica sand filter. After six-months of use, the sand filter achieved a 1.6 log-removal of particles with diameters greater than 2 μm; whereas the crushed glass filter achieved a 1.4 log removal for the similar particle size range. The observed removal performance was particularly encouraging given that the sand used had properties that were consistent with the standards set by the American Water Works Association. The crushed glass filter media was initially sieved and washed, but had no other pre-treatment preparation. Thus the application of crushed glass shows considerable promise as filter

Heterogeneous Nitrification in a Full Scale Rapid Sand Filter Treating Groundwater

DEFF Research Database (Denmark)

Lopato, Laure; Röttgers, Nina; Binning, Philip John

2013-01-01

Experiments were conducted to determine ammonium removal kinetics in an operating biologically active sand filter at a waterworks treating anaerobic groundwater. The ammonium load varied between 0.7 and 3 g N/h/m2 (concentration ranged from 0.23 to 0.78 mg N/l) and the inlet water flux varied...... nitrification rate constant was closely related to the water pore velocity which implies that the rate is strongly determined by the resistance to mass transport in the diffusion boundary layer around the sand grains. Read More: http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29EE.1943-7870.0000653...

Slow sand filters effectively reduce Phytophthora after a pathogen switch from Fusarium and a simulated pump failure.

Science.gov (United States)

Lee, Eric; Oki, Lorence R

2013-09-15

Slow sand filtration has been shown to effectively reduce Phytophthora zoospores in irrigation water. This experiment tested the reduction of Phytophthora colony forming units (CFUs) by slow sand filtration systems after switching the pathogen contaminating plant leachate from Fusarium to Phytophthora and the resilience of the system to a short period without water, as might be caused by a pump failure. The slow sand filtration system greatly reduced Phytophthora CFUs and transmission after switching the pathogens. In addition, Phytophthora reduction by the slow sand filter was equally effective before and after the simulated pump failure. Reduction of Fusarium was not seen by the SSFs, before or after the simulated pump failure. The results suggest that slow sand filters are effective at reducing larger organisms, such as Phytophthora zoospores, even after a pump failure or a change in pathogens. Copyright © 2013 Elsevier Ltd. All rights reserved.

Design parameters for waste effluent treatment unit from beverages production

Directory of Open Access Journals (Sweden)

Mona A. Abdel-Fatah

2017-09-01

Full Text Available Based on a successful experimental result from laboratory and bench scale for treatment of wastewater from beverages industry, an industrial and efficient treatment unit is designed and constructed. The broad goal of this study was to design and construct effluent, cost effective and high quality treatment unit. The used technology is the activated sludge process of extended aeration type followed by rapid sand filters and chlorination as tertiary treatment. Experimental results have been considered as the basis for full scale design of the industrial capacity of 1600 m3/day treatment plant. Final effluent characteristics after treatment comply with Egyptian legalizations after reducing COD and BOD5 by about 97% and 95% respectively. So it is recommended to reuse treated effluent in textile industry in dyeing process.

Using Combined Processes of Filtration and Ultraviolet Irradiation for Effluent Disinfection of Isfahan North Wastewater Treatment Plant in Pilot Scale

Directory of Open Access Journals (Sweden)

Mohammad Mehdi Amin

2011-07-01

Full Text Available This study was carried out to evaluate the secondary effluent disinfection of the Isfahannorth municipal wastewater treatment plant using filtration and UV technology in current operational condition. The combined system was used in series in pilot scale including: Pressure Sand Filter + Low Pressure (LP + Medium Pressure (MP UV Lamps. The UV dose varied according to the initial intensity of lamp, flow rate and influent transmittance. Total coliform (TC, fecal coliform (FC and fecal streptococcus (FS were analyzed as microbiological parameters in all effluent samples. TSS, BOD5, COD, VSS, pH and transmittance (UVT percentage were tested as physicochemical parameters, before and after the units. Results showed that the filtration with loading of 1050 lit/m2.hr, followed by MP lamp with dose of 230 mW.s/cm2 is an effective alternative to reduce the TC/FC and FS in the secondary effluent. The combined disinfection processes that were used in this study, could be met the standards of 1000 TC, and 400FC/100ml for effluent discharge to receiving waters or restricted reuses in the agriculture. This process can also inactivate the FS down to 6-log.Using low-pressure lamps due to low dose radiation for disinfection is not cost-effective. In this study, parasite egg counts due to lack of access to accurate identification techniques for alive cyst detection was not examined.

Design parameters for waste effluent treatment unit from beverages production

OpenAIRE

Mona A. Abdel-Fatah; H.O. Sherif; S.I. Hawash

2017-01-01

Based on a successful experimental result from laboratory and bench scale for treatment of wastewater from beverages industry, an industrial and efficient treatment unit is designed and constructed. The broad goal of this study was to design and construct effluent, cost effective and high quality treatment unit. The used technology is the activated sludge process of extended aeration type followed by rapid sand filters and chlorination as tertiary treatment. Experimental results have been con...

Integrated metagenomic and physiochemical analyses to evaluate the potential role of microbes in the sand filter of a drinking water treatment system.

Directory of Open Access Journals (Sweden)

Yaohui Bai

Full Text Available While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consumption. The results revealed that the biofilm developed rapidly within 2 days (reaching ≈ 10(11 prokaryotes per gram in the sand filter along with abiotic and biotic particulates accumulated in the interstitial spaces. Bacteria (up to 90% dominated the biofilm microbial community, with Alphaproteobacteria being the most common class. Thaumarchaeota was the sole phylum of Archaea, which might be involved in ammonia oxidation. Function annotation of metagenomic datasets revealed a number of aromatic degradation pathway genes, such as aromatic oxygenase and dehydrogenase genes, in the biofilm, suggesting a significant role for microbes in the breakdown of aromatic compounds in groundwater. Simultaneous nitrification and denitrification pathways were confirmed as the primary routes of nitrogen removal. Dissolved heavy metals in groundwater, e.g. Mn(2+ and As(3+, might be biologically oxidized to insoluble or easily adsorbed compounds and deposited in the sand filter. Our study demonstrated that the role of the microbial community in the sand filter treatment system are critical to effective water purification in drinking water.

Integrated metagenomic and physiochemical analyses to evaluate the potential role of microbes in the sand filter of a drinking water treatment system.

Science.gov (United States)

Bai, Yaohui; Liu, Ruiping; Liang, Jinsong; Qu, Jiuhui

2013-01-01

While sand filters are widely used to treat drinking water, the role of sand filter associated microorganisms in water purification has not been extensively studied. In the current investigation, we integrated molecular (based on metagenomic) and physicochemical analyses to elucidate microbial community composition and function in a common sand filter used to treat groundwater for potable consumption. The results revealed that the biofilm developed rapidly within 2 days (reaching ≈ 10(11) prokaryotes per gram) in the sand filter along with abiotic and biotic particulates accumulated in the interstitial spaces. Bacteria (up to 90%) dominated the biofilm microbial community, with Alphaproteobacteria being the most common class. Thaumarchaeota was the sole phylum of Archaea, which might be involved in ammonia oxidation. Function annotation of metagenomic datasets revealed a number of aromatic degradation pathway genes, such as aromatic oxygenase and dehydrogenase genes, in the biofilm, suggesting a significant role for microbes in the breakdown of aromatic compounds in groundwater. Simultaneous nitrification and denitrification pathways were confirmed as the primary routes of nitrogen removal. Dissolved heavy metals in groundwater, e.g. Mn(2+) and As(3+), might be biologically oxidized to insoluble or easily adsorbed compounds and deposited in the sand filter. Our study demonstrated that the role of the microbial community in the sand filter treatment system are critical to effective water purification in drinking water.

Geo synthetics in hydraulic and coastal engineering: Filters, revetments and sand filled structures

International Nuclear Information System (INIS)

Bezuijen, A.; Pilarczyk, K. W.

2014-01-01

The paper deals with 2 applications of geo textiles in coastal and hydraulic engineering: Geo textiles in filters and revetments; and geo textiles in sand filled structure. Geo textiles are often replacing granular filters. However, they have different properties than a granular filter. For the application of geo textiles in revetments, the consequences of the different properties will be shown: how permeability is influenced by a geo textile and what can be the consequences of the weight differences between granular and geo textile filters. In the other application, the filter properties of geo textiles are only secondary. In geo textile tubes and containers the geo textile is used as wrapping material to create large unties that will not erode during wave attach. the structures with geo textile tubes and containers serve as an alternative for rock based structures. The first of these structures were more or less constructed by trial and error, but research on the shape of the structures, the stability under wave attach and the durability of the used of the used material has given the possibility to use design tools for these structures. Recently also the morphological aspects of these structures have been investigated. This is of importance because regularly structures with geo textile tubes fail due to insufficient toe protection against the scour hole that that develops in front of the structure, leading to undermining of the structure. Recent research in the Dealt Flume of Deltares and the Large Wave Flume in Hannover has led to better understanding what mechanisms determine the stability under wave attach. It is shown that also the degree of filling is of importance and the position of the water level with respect to the tube has a large influence. (Author)

Performance of Hybrid Photocatalytic-Ceramic Membrane System for the Treatment of Secondary Effluent.

Science.gov (United States)

Song, Lili; Zhu, Bo; Gray, Stephen; Duke, Mikel; Muthukumaran, Shobha

2017-03-28

Evaluation of an advanced wastewater treatment system that combines photocatalysis with ceramic membrane filtration for the treatment of secondary effluent was undertaken. The results showed that, after photocatalysis and ceramic membrane filtration, the removal of dissolved organic carbon and UV 254 was 60% and 54%, respectively, at a concentration of 4 g/L of TiO₂. Dissolved organic matter (DOM) present in the secondary effluent was characterised with a liquid chromatography-organic carbon detector (LC-OCD) technique. The results showed low removal of humics, building blocks, the other oxidation by-products and no removal of biopolymers after TiO₂/UV photocatalytic treatment. This suggested that the radical non-selective oxidation mechanisms of TiO₂/UV process resulted in secondary effluent in which all of the DOM fractions were present. However, the hybrid system was effective for removing biopolymers with the exception of low molecular weight (LMW) compounds acids, which accumulated from the beginning of the reaction. In addition, monitoring of the DOM fractions with LC-OCD analysis demonstrated that the reduction of the effluent aromaticity was not firmly correlated with the removal of humic substances for the combined processes.

Determination and removal of antibiotics in secondary effluent using a horizontal subsurface flow constructed wetland.

Science.gov (United States)

Zhang, Chunhui; Ning, Ke; Zhang, Wenwen; Guo, Yuanjie; Chen, Jun; Liang, Chen

2013-04-01

Increased attention is currently being directed towards the potential negative effects of antibiotics and other PPCPs discharged into the aquatic environment via municipal WWTP secondary effluents. A number of analytical methods, such as high performance liquid chromatography technologies, including a high performance liquid chromatography-fluorescence method (HPLC-FLD), high performance liquid chromatography-UV detection method (HPLC-UV) and high performance liquid chromatography-mass spectrometry method (HPLC-MS), have been suggested as determination technologies for antibiotic residues in water. In this study, we implement a HPLC-MS/MS combined method to detect and analyze antibiotics in WWTP secondary effluent and apply a horizontal subsurface flow constructed wetland (CW) as an advanced wastewater treatment for removing antibiotics in the WWTP secondary effluent. The results show that there were 2 macrolides, 2 quinolones and 5 sulfas in WWTP secondary effluent among all the 22 antibiotics considered. After the CW advanced treatment, the concentration removal efficiencies and removal loads of 9 antibiotics were 53-100% and 0.004-0.7307 μg m(-2) per day, respectively.

Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2016-01-01

The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous...

Efficiency of combined process of ozone and bio-filtration in the treatment of secondary effluent.

Science.gov (United States)

Tripathi, Smriti; Tripathi, B D

2011-07-01

The present work was aimed at studying the efficiency of the combined process of biofiltration with ozonation to improve the quality of secondary effluent. The secondary effluent from the Dinapur Sewage Treatment Plant Varanasi, India was used in this work. The process of biofiltration with the plant species of Eichornia crassipes and Lemna minor, at a flow rate of 262 ml min(-1) and plant density of 30 mg L(-1) for 48 h, in combination with the process of ozonation with ozone dose of 10 mg L(-1) and contact time of 5 min was applied. Results revealed that combined process was statistically most suitable for the highest degradation of physico-chemical and microbial parameters with improving BDOC value. The biofiltration process is able to remove highest percentage of toxic heavy metals from the secondary effluent without production of toxicity. This technique is highly recommendable for tropical wastewater where sewage is mixed with industrial effluents. Copyright © 2011 Elsevier Ltd. All rights reserved.

Eliminating radium from uranium mill acid effluent with barium chloride-sodium carbonate precipitation

International Nuclear Information System (INIS)

Xiao Jiayuan

1998-01-01

The eliminating radium procedure, barium chloride-sodium carbonate-sand filtering, being used, radium can be eliminated to 3.7 x 10 -2 Bq/L order of magnitude from uranium mill acid effluents which contain 3.7 Bq/L Ra and pH 6∼9 when Ba 2+ is added by 3∼5 mg per litre, Na 2 CO 3 5mg. The radium elimination rate is more than 90%

Economic Assessment of an Integrated Membrane System for Secondary Effluent Polishing for Unrestricted Reuse

Directory of Open Access Journals (Sweden)

Gideon Oron

2012-03-01

Full Text Available Extra treatment stages are required to polish the secondary effluent for unrestricted reuse, primarily for agricultural irrigation. Improved technology for the removal of particles, turbidity, bacteria and cysts, without the use of disinfectants is based on MicroFiltration (MF and UltraFiltration (UF membrane technology and in series with Reverse Osmosis (RO for dissolved solids removal. Field experiments were conducted using a mobile UF and RO membrane pilot unit at a capacity of around 1.0 m3/hr. A management model was defined and tested towards optimal polishing of secondary effluent. The two major purposes of the management model are: (i to delineate a methodology for economic assessment of optimal membrane technology implementation for secondary effluent upgrading for unrestricted use, and; (ii to provide guidelines for optimal RO membrane selection in regards to the pretreatment stage. The defined linear model takes into account the costs of the feed secondary effluent, the UF pretreatment and the RO process. Technological constraints refer primarily to the longevity of the membrane and their performance. Final treatment cost (the objective function includes investment, operation and maintenance expenses, UF pretreatment, RO treatment, post treatment and incentive for low salinity permeate use. The cost range of water for irrigation according to the model is between 15 and 42 US cents per m3.

A novel bench-scale column assay to investigate site-specific nitrification biokinetics in biological rapid sand filters

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2013-01-01

A bench-scale assay was developed to obtain site-specific nitrification biokinetic information from biological rapid sand filters employed in groundwater treatment. The experimental set-up uses granular material subsampled from a full-scale filter, packed in a column, and operated with controlled...

Polishing of Anaerobic Secondary Effluent and Symbiotic Bioremediation of Raw Municipal Wastewater by Chlorella Vulgaris

KAUST Repository

Cheng, Tuoyuan

2016-01-01

To assess polishing of anaerobic secondary effluent and symbiotic bioremediation of primary effluent by microalgae, bench scale bubbling column reactors were operated in batch modes to test nutrients removal capacity and associated factors. Chemical

Comparing mixed-media and conventional slow-sand filters for arsenic removal from groundwater

NARCIS (Netherlands)

Śmiech, Karolina M.; Tolsma, Aize; Kovács, Tímea; Dalbosco, Vlade; Yasadi, Kamuran; Groendijk, Leo; Agostinho, Luewton L.F.

2018-01-01

Arsenic contamination of groundwater is a major public health concern worldwide. The problem has been reported mainly in southern Asia and, especially, in Bangladesh. Slow-sand filters (SSF) augmented with iron were proven to be a simple, low-cost and decentralized technique for the treatment of

Impact of organic fractions identified by SEC and fluorescence EEM on the hydraulic reversibility of ultrafiltration membrane fouling by secondary effluents

KAUST Repository

Haberkampa, Jens

2011-05-01

Loss of membrane filtration performance due to organic fouling is still a significant drawback for the application of low-pressure membranes in tertiary wastewater treatment. The present study investigates the relevance of different organic fractions present in secondary effluents in terms of hydraulically reversible and irreversible fouling of hollow-fibre ultrafiltration membranes. A good correlation between the hydraulically reversible filtration resistance and the total organic biopolymer concentration according to size exclusion chromatography (SEC) was observed. Qualitatively biopolymers consist mainly of polysaccharides as well as proteins with high molecular weight. Polysaccharides are retained by the membrane pores, but can be removed by simple UF backwashing. On the other hand, fluorescence excitation-emission matrix (EEM) analysis indicates that the extent of the hydraulically irreversible fouling correlates with the presence of protein-like substances. Removal of protein-like substances by biological slow sand filtration or chemical coagulation results in the significant reduction of the hydraulically irreversible fouling, which is presumably due to proteins in the molecular range of biopolymers. In contrast to the comparatively low sensitivity of colorimetric methods for the analysis of proteins and polysaccharides, the combined application of size exclusion chromatography and fluorescence EEM analysis is a promising tool for the determination of the organic fouling propensity of secondary effluents. ©2011 Desalination Publications. All rights reserved.

Impact of organic fractions identified by SEC and fluorescence EEM on the hydraulic reversibility of ultrafiltration membrane fouling by secondary effluents

KAUST Repository

Haberkampa, Jens; Ernst, Mathias; Paar, Hendrik; Pallischeck, Daniela; Amy, Gary L.; Jekel, Martin R.

2011-01-01

Loss of membrane filtration performance due to organic fouling is still a significant drawback for the application of low-pressure membranes in tertiary wastewater treatment. The present study investigates the relevance of different organic fractions present in secondary effluents in terms of hydraulically reversible and irreversible fouling of hollow-fibre ultrafiltration membranes. A good correlation between the hydraulically reversible filtration resistance and the total organic biopolymer concentration according to size exclusion chromatography (SEC) was observed. Qualitatively biopolymers consist mainly of polysaccharides as well as proteins with high molecular weight. Polysaccharides are retained by the membrane pores, but can be removed by simple UF backwashing. On the other hand, fluorescence excitation-emission matrix (EEM) analysis indicates that the extent of the hydraulically irreversible fouling correlates with the presence of protein-like substances. Removal of protein-like substances by biological slow sand filtration or chemical coagulation results in the significant reduction of the hydraulically irreversible fouling, which is presumably due to proteins in the molecular range of biopolymers. In contrast to the comparatively low sensitivity of colorimetric methods for the analysis of proteins and polysaccharides, the combined application of size exclusion chromatography and fluorescence EEM analysis is a promising tool for the determination of the organic fouling propensity of secondary effluents. ©2011 Desalination Publications. All rights reserved.

Effects of sewage effluent and ethynyl oestradiol upon molecular markers of oestrogenic exposure, maturation and reproductive success in the sand goby (Pomatoschistus minutus, Pallas)

International Nuclear Information System (INIS)

Robinson, Craig D.; Brown, Elaine; Craft, John A.; Davies, Ian M.; Moffat, Colin F.; Pirie, David; Robertson, Fiona; Stagg, Ronald M.; Struthers, Susan

2003-01-01

Male fish in several UK estuaries are known to be exposed to oestrogenic contamination, and whilst a limited number of studies have shown that exposure to oestrogens can reduce the reproductive success of fish, the impact of environmentally relevant exposures is less clear. The aim of this study was, therefore, to investigate the effects of exposure to environmentally realistic concentrations of a sewage effluent and the synthetic oestrogen 17α-ethynyl oestradiol (EE 2 ) upon the reproductive success of a marine fish. Sand goby (Pomatoschistus minutus) were exposed for 7 months to EE 2 or a sewage effluent containing known xeno-oestrogens (alkylphenol polyethoxylates) and bred using within treatment crosses. Nominal exposure concentrations were 6 ng l -1 EE 2 , 0.3 or 0.03% v/v sewage effluent. At the end of the breeding trials, expression of hepatic zona radiata protein (Zrp) and vitellogenin (Vtg) mRNA were determined using two recently developed cDNA probes. Exposure to 6 ng l -1 EE 2 induced Zrp and Vtg mRNA expression in male and female sand goby, impaired male maturation and reproductive behaviour, reduced female fecundity and reduced egg fertility. As a consequence, fertile egg production of the EE 2 -exposed population was reduced by 90%. Exposure to sewage effluent (0.3% v/v) increased adult mortality and female Zrp and Vtg mRNA expression, but did not induce male vitellogenesis. Exposure to EE 2 and 0.3% v/v sewage effluent impaired development of the male urogenital papilla. Fish exposed to 0.03% v/v sewage effluent produced more fertile eggs than those exposed to 0.3% effluent, or those receiving no effluent. It is concluded that male vitellogenesis in an oestrogenically exposed population may be accompanied by reduced reproductive success, but that it may not be indicative of altered reproductive output in a population exposed to an industrial sewage effluent

Particle size distribution and property of bacteria attached to carbon fines in drinking water treatment

Directory of Open Access Journals (Sweden)

Wang Leilei

2008-06-01

Full Text Available The quantitative change and size distribution of particles in the effluents from a sand filter and a granular activated carbon (GAC filter in a drinking water treatment plant were investigated. The average total concentration of particles in the sand filter effluent during a filter cycle was 148 particles/mL, 27 of which were larger than 2 µm in size. The concentration in the GAC effluent (561 particles/mL was significantly greater than that in the sand filter effluent. The concentration of particles larger than 2 µm in the GAC filter effluent reached 201 particles/mL, with the amount of particles with sizes between 2 µm and 15 µm increasing. The most probable number (MPN of carbon fines reached 43 unit/L after six hours and fines between 0.45 µm and 8.0 µm accounted for more than 50%. The total concentration of outflowing bacteria in the GAC filter effluent, 350 CFU (colony-forming units/mL, was greater than that in the sand filter effluent, 210 CFU/mL. The desorbed bacteria concentration reached an average of 310 CFU/mg fines. The disinfection efficiency of desorbed bacteria was lower than 40% with 1.5 mg/L of chlorine. The disinfection effect showed that the inactivation rate with 2.0 mg/L of chloramine (90% was higher than that with chlorine (70%. Experimental results indicated that the high particle concentration in raw water and sedimentation effluent led to high levels of outflowing particles in the sand filter effluent. The activated carbon fines in the effluent accounted for a small proportion of the total particle amount, but the existing bacteria attached to carbon fines may influence the drinking water safety. The disinfection efficiency of desorbed bacteria was lower than that of free bacteria with chlorine, and the disinfection effect on bacteria attached to carbon fines with chloramine was better than that with only chlorine.

Filtration device for active effluents

International Nuclear Information System (INIS)

Guerin, M.; Meunier, G.

1994-01-01

Among the various techniques relating to solid/liquid separations, filtration is currently utilized for treating radioactive effluents. After testing different equipments on various simulated effluents, the Valduc Center has decided to substitute a monoplate filter for a rotative diatomite precoated filter

Comparison between Removal Efficiency of Slag, zeolite, and Conventional media in slow sand Filter for Removal of Lead and Cadmium from Water Resources

Directory of Open Access Journals (Sweden)

A Ebrahimi

2016-03-01

Full Text Available Introduction: Heavy metals owing to their health hazards and high toxicity in low concentration for human and environment have very concern and attention. Slow sand filter is one of the simple and cost-effective for removal of these pollutants. In this method, media play an important role for removal of pollutant. Therefore, the aim of this study was investigation of different media like slag, zeolite, and conventional media in slow sand filter for removal of lead and cadmium. Methods: In this research there are three beds filter include typical filter bed, slag and zeolite that used in pilot plant for investigation of lead and cadmium removal at three concentration of 0.1T 1 and 10 ppm. Each of filters has an internal diameter of 8 cm and a height of 120 cm with Plexiglas, which have a continuous flow operation. Results: The removal efficiency of turbidity by three typical filter bed, slag, and zeolite with initial turbidity of 13 NTU was 46%, 77%, and 89% respectively. Removal efficiency of lead without turbidity was 70.3%, 79%, and 59.8% respectively for 0.1 ppm lead. For 1 ppm, concentration of lead removal efficiency was 51.8%, 52.7% and 52.6% respectively and for 10 ppm it was 53.4%, 57.8%, and 59.8% respectively. Cadmium removal for these media was 23.4%, 37.5%, and 59.4% respectively at 0.1 ppm cadmium. At 1 ppm of cadmium concentration, it was 37.9%, 45% and 41.3% respectively and at 10 ppm concentration of cadmium it was 68.3%, 68.6% and 67% respectively. Conclusion: Slag and zeolite beds are more efficiently than the conventional sand beds in the slow sand filter, so it can be used instead of the usual sand for removing lead and cadmium from resources water.

Radium desorption, manganese and iron dissolution from sand filters of a conventional ground water treatment plant under reductive conditions

International Nuclear Information System (INIS)

Al-Hobaib, A.S.; Al-Sulaiman, K.M.; Al-Dhayan, D.M.; Al-Suhybani, A.A.

2006-01-01

Sand filters are used as a filter bed in many ground water treatment plants to remove the physical contaminants and oxidation products. A build-up of radioactivity may take place on the granules, where iron and manganese oxides are deposited and form thin films on the surface of sand filter. The oxides of iron and manganese play an important role in adsorbing radium from ground water. The disposal of those granules makes a significant problem. A batch technique is used for solubilization of radium from sand filters in the presence of some organic acids, which act as reducing agents. These acids are formic acid, acetic acid, benzoic acid, succinic acid, oxalic acid, phthalic acid, and adipic acid. The data were obtained as a function of acidity, temperature, contact time and liquid/solid ratio particle size and shaking speed. It was found that oxalic acid was the best for radium removal. The effectiveness of these acids on radium removal was as follows: oxalic acid > phthalic acid > adipic acid > succinic acid > formic acid > acetic acid. The maximum removal obtained was 69.9% at 1M oxalic acid at 8 ml/g ratio. Reaction kinetics and mechanism parameters of the dissolution process were studied and compared with other published data. (author)

Phosphate limitation in biological rapid sand filters used to remove ammonium from drinking water

DEFF Research Database (Denmark)

Lee, Carson Odell; Albrechtsen, Hans-Jørgen; Smets, Barth F.

2013-01-01

Removing ammonium from drinking water is important for maintaining biological stability in distribution systems. This is especially important in regions that do not use disinfectants in the treatment process or keep a disinfectant residual in the distribution system. Problems with nitrification c...... a pilot scale sand column which initial analysis confirmed performed similarly to the full scale filters. Long term increased ammonium loads were applied to the pilot filter both with and without phosphate addition. Phosphate was added at a concentration of 0.5 mg PO4-P/L to ensure...

Retention soil filter as post-treatment step to remove micropollutants from sewage treatment plant effluent

NARCIS (Netherlands)

Brunsch, Andrea F.; Laak, ter Thomas L.; Christoffels, Ekkehard; Rijnaarts, Huub H.M.; Langenhoff, Alette A.M.

2018-01-01

Retention soil filters (RSFs) are a specific form of vertical flow constructed wetlands for the treatment of rain water and/or wastewater. We have tested 3 pilot RSFs to investigate removal of dissolved organic carbon (DOC) and 14 different organic micropollutants (OMPs) from the effluent of a

Desalination of effluent using fin type solar still

Energy Technology Data Exchange (ETDEWEB)

Velmurugan, V. [Department of Mechanical Engineering, Infant Jesus College of Engineering, Thoothukudi, Tamil Nadu 628 851 (India); Deenadayalan, C.K.; Vinod, H.; Srithar, K. [Department of Mechanical Engineering, Thiagarajar College of Engineering, Madurai, Tamil Nadu 625 015 (India)

2008-11-15

In this work, an attempt is made to produce potable water from industrial effluents. An ordinary basin type solar still integrated with fins at the basin plate is used for experimentation. Since industrial effluent is used as feed, before this still, an effluent settling tank is provided to get clarified effluent. This effluent settling tank is fabricated with three chambers, consists of pebble, coal and sand for settling the impurities and removing the bacteria in the effluents. Sponges, pebbles, black rubber and sand are used in the fin type single basin solar still for enhancing the yield. Results show that the productivity increases considerably due to this modification. A theoretical analysis is also carried out which, closely converges with experimental results. The economic analysis proved that the approximate payback period of such kinds of still is 1 year. (author)

Evidence of co-metabolic bentazone transformation by methanotrophic enrichment from a groundwater-fed rapid sand filter

DEFF Research Database (Denmark)

Hedegaard, Mathilde Jørgensen; Deliniere, Hélène; Prasse, Carsten

2018-01-01

from 58 to 158, well within the range for methanotrophic co-metabolic degradation of trace contaminants calculated from the literature, with normalized substrate preferences varying from 3 to 400. High-resolution mass spectrometry revealed formation of the transformation products (TPs) 6-OH, 8-OH......The herbicide bentazone is recalcitrant in aquifers and is therefore frequently detected in wells used for drinking water production. However, bentazone degradation has been observed in filter sand from a rapid sand filter at a waterworks with methane-rich groundwater. Here, the association between...... and bentazone at concentrations below 2 mg/L showed methanotrophic co-metabolic bentazone transformation: The culture removed 53% of the bentazone in 21 days in presence of 5 mg/L of methane, while only 31% was removed in absence of methane. Addition of acetylene inhibited methane oxidation and stopped...

Preliminary study on filamentous particle distribution in septic tank effluent and their impact on filter cake development.

Science.gov (United States)

Spychała, Marcin; Nieć, Jakub; Pawlak, Maciej

2013-01-01

In this paper, the preliminary study on the impact of filamentous particles (FP) in the septic tank effluent (STE) on filter cake (FC) development was presented. The number, length and diameter (30 p./cm3, 451 and 121 microm, respectively, on average) of FPs were measured using microscope image analysis of STE samples condensed using a vacuum evaporation set. Results of this study showed, that 0.73% of volatile suspended solids (VSSs) mass from the STE occurs in the form of FPs. No correlation between FP total mass and VSS was found. An experiment with a layer of FPs simulated by ground toilet paper was conducted and showed the impact of this layer (4.89 mg/cm2) on wastewater hydraulic conductivity--for an FC with FPs (FC-FP), hydraulic conductivity was seven times lower than for the FC without the FP layer, and on outflow quality (lower concentration of organic matter expressed as chemical oxygen demand (COD) in effluent from the FC-FP filter than in the effluent from the FC filter: 618 and 732 gO2/m3, respectively). Despite a relatively small amount of FPs in STE solids (as volume fraction), they play an important role in FC development due to their relatively high length and low degradability. Probably relatively small pores of the FC containing FPs (FC-FP) caused a small particle blocking and a decrease in permeability.

Disinfection of tertiary wastewater effluent prior to river discharge using peracetic acid; treatment efficiency and results on by-products formed in full scale tests.

Science.gov (United States)

Pedersen, Per Overgaard; Brodersen, Erling; Cecil, David

2013-01-01

This is an investigation of chemical disinfection, with peracetic acid (PAA), in a tertiary sand filter at a full scale activated sludge plant with nitrification/denitrification and P-removal. The reduction efficiency of Escherichia coli and intestinal enterococci in the sand filter is reported. E. coli log reductions of between 0.4 and 2.2 were found with contact times from 6 to 37 min and with dosing from 0 to 4.8 mg L(-1). The average log reduction was 1.3. The decomposition products, bromophenols, chlorophenols and formaldehyde and residual H2O2 were measured before and after the sand filter. The residual H2O2 concentration in the effluent was critical at short contact times and high dosages of PAA due to the discharge limit of 25 μg L(-1). The other three products could not be detected at 0.1 μg L(-1) levels. The chemical cost of PAA dosing is estimated to be 0.039 US$ m(-3) treated wastewater.

Bioaugmentation of rapid sand filters by microbiome priming with a nitrifying consortium will optimize production of drinking water from groundwater

DEFF Research Database (Denmark)

Albers, Christian Nyrop; Ellegaard-Jensen, Lea; Hansen, Lars Hestbjerg

2018-01-01

. It is shown that nitrifying communities could be enriched by microbiomes from well-functioning rapid sand filters in waterworks and that the enriched nitrifying consortium could be used to inoculate fresh filters, significantly shortening the time taken for the nitrification process to start. The key...

Computational fluid dynamics simulation of transport and retention of nanoparticle in saturated sand filters

International Nuclear Information System (INIS)

Hassan, Ashraf Aly; Li, Zhen; Sahle-Demessie, Endalkachew; Sorial, George A.

2013-01-01

Highlights: ► Breakthrough curves used to study fate of NPs in slow sand filters (SSF). ► CFD simulate transport, attachment/detachment of NPs in SSFs. ► CFD predicted spatial and temporal changes for transient concentrations of NPs. ► CFD predicts low concentrations and steady NP influx would not be retained by SSFs. ► Pulse input is retained with outlet concentration of 0.2% of the inlet. -- Abstract: Experimental and computational investigation of the transport parameters of nanoparticles (NPs) flowing through porous media has been made. This work intends to develop a simulation applicable to the transport and retention of NPs in saturated porous media for investigating the effect of process conditions and operating parameters such, as ion strength, and filtration efficiency. Experimental data obtained from tracer and nano-ceria, CeO 2 , breakthrough studies were used to characterize dispersion of nanoparticle with the flow and their interaction with sand packed columns with different heights. Nanoparticle transport and concentration dynamics were solved using the Eulerian computational fluid dynamics (CFD) solver ANSYS/FLUENT ® based on a scaled down flow model. A numerical study using the Navier–Stokes equation with second order interaction terms was used to simulate the process. Parameters were estimated by fitting tracer, experimental NP transport data, and interaction of NP with the sand media. The model considers different concentrations of steady state inflow of NPs and different amounts of spike concentrations. Results suggest that steady state flow of dispersant-coated NPs would not be retained by a sand filter, while spike concentrations could be dampened effectively. Unlike analytical solutions, the CFD allows estimating flow profiles for structures with complex irregular geometry and uneven packing

Computational fluid dynamics simulation of transport and retention of nanoparticle in saturated sand filters

Energy Technology Data Exchange (ETDEWEB)

Hassan, Ashraf Aly [U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 W. Martin Luther King Drive, Cincinnati, OH 45268 (United States); Li, Zhen [School of Energy, Environmental, Biological, and Medical Engineering, Environmental Engineering Program, University of Cincinnati, Cincinnati, OH (United States); Sahle-Demessie, Endalkachew, E-mail: sahle-demessie.endalkachew@epa.gov [U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 W. Martin Luther King Drive, Cincinnati, OH 45268 (United States); Sorial, George A. [School of Energy, Environmental, Biological, and Medical Engineering, Environmental Engineering Program, University of Cincinnati, Cincinnati, OH (United States)

2013-01-15

Highlights: ► Breakthrough curves used to study fate of NPs in slow sand filters (SSF). ► CFD simulate transport, attachment/detachment of NPs in SSFs. ► CFD predicted spatial and temporal changes for transient concentrations of NPs. ► CFD predicts low concentrations and steady NP influx would not be retained by SSFs. ► Pulse input is retained with outlet concentration of 0.2% of the inlet. -- Abstract: Experimental and computational investigation of the transport parameters of nanoparticles (NPs) flowing through porous media has been made. This work intends to develop a simulation applicable to the transport and retention of NPs in saturated porous media for investigating the effect of process conditions and operating parameters such, as ion strength, and filtration efficiency. Experimental data obtained from tracer and nano-ceria, CeO{sub 2}, breakthrough studies were used to characterize dispersion of nanoparticle with the flow and their interaction with sand packed columns with different heights. Nanoparticle transport and concentration dynamics were solved using the Eulerian computational fluid dynamics (CFD) solver ANSYS/FLUENT{sup ®} based on a scaled down flow model. A numerical study using the Navier–Stokes equation with second order interaction terms was used to simulate the process. Parameters were estimated by fitting tracer, experimental NP transport data, and interaction of NP with the sand media. The model considers different concentrations of steady state inflow of NPs and different amounts of spike concentrations. Results suggest that steady state flow of dispersant-coated NPs would not be retained by a sand filter, while spike concentrations could be dampened effectively. Unlike analytical solutions, the CFD allows estimating flow profiles for structures with complex irregular geometry and uneven packing.

Polishing of anaerobic secondary effluent by Chlorella vulgaris under low light intensity

KAUST Repository

Cheng, Tuoyuan; Wei, Chunhai; Leiknes, TorOve

2017-01-01

To investigate anaerobic secondary effluent polishing by microalgae (Chlorella vulgaris) under low light intensity (14 μmol/m2/s), bubbling column reactors were operated in batches of 8 d with initial ammonium nitrogen 10-50 mg/L, initial phosphate phosphorus 2-10 mg/L and microalgal seed 40 mg/L. Maximum microalgal biomass and minimum generation time were 370.9 mg/L and 2.5 d, respectively. Nitrogen removal (maximum 99.6%) was mainly attributed to microalgal growth rate, while phosphorus removal (maximum 49.8%) was related to microalgal growth rate, cell phosphorus content (maximum 1.5%) and initial nutrients ratio. Dissolved microalgal organics release in terms of chemical oxygen demand (maximum 63.2 mg/L) and hexane extractable material (i.e., oil and grease, maximum 8.5 mg/L) was firstly reported and mainly affected by nitrogen deficiency and deteriorated effluent quality. Ultrafiltration critical flux (16.6-39.5 L/m2/h) showed negative linear correlation to microalgal biomass. Anaerobic membrane bioreactor effluent polishing showed similar results with slight inhibition to synthetic effluent.

Polishing of anaerobic secondary effluent by Chlorella vulgaris under low light intensity

KAUST Repository

Cheng, Tuoyuan

2017-05-29

To investigate anaerobic secondary effluent polishing by microalgae (Chlorella vulgaris) under low light intensity (14 μmol/m2/s), bubbling column reactors were operated in batches of 8 d with initial ammonium nitrogen 10-50 mg/L, initial phosphate phosphorus 2-10 mg/L and microalgal seed 40 mg/L. Maximum microalgal biomass and minimum generation time were 370.9 mg/L and 2.5 d, respectively. Nitrogen removal (maximum 99.6%) was mainly attributed to microalgal growth rate, while phosphorus removal (maximum 49.8%) was related to microalgal growth rate, cell phosphorus content (maximum 1.5%) and initial nutrients ratio. Dissolved microalgal organics release in terms of chemical oxygen demand (maximum 63.2 mg/L) and hexane extractable material (i.e., oil and grease, maximum 8.5 mg/L) was firstly reported and mainly affected by nitrogen deficiency and deteriorated effluent quality. Ultrafiltration critical flux (16.6-39.5 L/m2/h) showed negative linear correlation to microalgal biomass. Anaerobic membrane bioreactor effluent polishing showed similar results with slight inhibition to synthetic effluent.

Metal oxide/hydroxide-coated dual-media filter for simultaneous removal of bacteria and heavy metals from natural waters.

Science.gov (United States)

Ahammed, M Mansoor; Meera, V

2010-09-15

The present study was conducted to compare the performance of a dual-media filter consisting of manganese oxide-coated (MOCS) and iron hydroxide-coated sand (IOCS) with that of IOCS filter and uncoated sand filter in treating water contaminated by microorganisms, heavy metals and turbidity with a view to its use in simple household water purification devices in developing countries. Long-duration column tests were conducted using two natural waters namely, roof-harvested rainwater and canal water. Performance of the filters showed that dual-media filter was more efficient in removing bacteria and heavy metals compared to IOCS filter, while uncoated sand filter showed very poor performance. The average effluent levels for dual-media filter when tested with rainwater were: turbidity 1.0+/-0.1 NTU; total coliforms 3+/-2 MPN/100 mL; heterotrophic plate count 170+/-20 CFU/mL; zinc 0.06+/-0.01 mg/L, while that for IOCS filter were: turbidity 1.0+/-0.1 NTU; total coliforms 4+/-2 MPN/100 mL; heterotrophic plate count 181+/-37 CFU/mL; zinc 0.20+/-0.07 mg/L. Similar results were obtained for canal water also. Up to 900 bed volumes (BV) could be treated without affecting the efficiency in the case of rainwater, while the filter operation had to be terminated after 500 BV due to excessive headloss in the case of canal water. The study thus showed the potential of the dual-media for use in low-cost household water filters for purification of natural waters. Copyright 2010 Elsevier B.V. All rights reserved.

Disinfection of Water and Wastewater Using Gamma Irradiation in Isfahan Water and Wastewater Treatment Plants

Directory of Open Access Journals (Sweden)

Hassan Hashemi

2011-01-01

Full Text Available To investigate the effect of gamma irradiation on the disinfection of water and wastewater, water samples were collected from raw and filtered water and wastewater samples were taken from the effluent of the secondary sedimentation, polished effluent (1-day retention time, and also from filtered (rapid sand filter effluent. The samples were irradiated with gamma collimated beam in a batch system using a Co-60 therapeutic gamma radiation machine with a radioactive source emission rate of 405.38CGy/min at different doses of 20-160 Gy and 80-240 Gy, respectively. The samples were analyzed before and after irradiation for total and fecal coliforms. It was observed that nearly 100% reduction was achieved in total and fecal coliforms in water samples treated with a dose of 160 Gy. Depending on effluent quality, disinfection efficiencies achieved using 240 Gy gamma irradiation for inactivation of total coliforms in wastewater samples were 83, 64, and 56 percent for filtered, clarified, and secondary effluents, respectively. The same values were nearly 81, 58, and 46 percent, respectively, for inactivation of fecal coliforms. At lower doses of 120-240Gy, the coliform bacteria were successfully inactivated. It was concluded that a linear correlation holds between the dose delivered and the inactivation of microorganisms, so that inactivation increases with increasing irradiation time.

Algal-based immobilization process to treat the effluent from a secondary wastewater treatment plant (WWTP)

International Nuclear Information System (INIS)

He Shengbing; Xue Gang

2010-01-01

Algal-based immobilization process was applied to treat the effluent from a secondary wastewater treatment plant. Batch test proved that algae could attach onto fiber-bundle carrier in 7 days, and then the algal-based immobilization reactor could reduce TN (total nitrogen) and TP (total phosphorus) significantly within 48 h. Based on the above investigations, the hydraulic retention time (HRT) of the algal-based immobilization reactor in continuous operation mode was determined to be 2 days. During the 91 days of experiment on the treating secondary effluent of Guang-Rao wastewater treatment plant, it was found that the fiber-bundle carrier could collect the heterobacteria and nitrifying bacteria gradually, and thus improved the COD removal efficiency and nitrification performance step by step. Results of the continuous operation indicated that the final effluent could meet the Chinese National First A-level Sewage Discharge Standard when the algal-based immobilization reactor reached steady state.

Peracetic acid for secondary effluent disinfection: a comprehensive performance assessment.

Science.gov (United States)

Antonelli, M; Turolla, A; Mezzanotte, V; Nurizzo, C

2013-01-01

The paper is a review of previous research on secondary effluent disinfection by peracetic acid (PAA) integrated with new data about the effect of a preliminary flash-mixing step. The process was studied at bench and pilot scale to assess its performance for discharge in surface water and agricultural reuse (target microorganisms: Escherichia coli and faecal coliform bacteria). The purposes of the research were: (1) determining PAA decay and disinfection kinetics as a function of operating parameters, (2) evaluating PAA suitability as a disinfectant, (3) assessing long-term disinfection efficiency, (4) investigating disinfected effluent biological toxicity on some aquatic indicator organisms (Vibrio fischeri, Daphnia magna and Selenastrum capricornutum), (5) comparing PAA with conventional disinfectants (sodium hypochlorite, UV irradiation). PAA disinfection was capable of complying with Italian regulations on reuse (10 CFU/100 mL for E. coli) and was competitive with benchmarks. No regrowth phenomena were observed, as long as needed for agricultural reuse (29 h after disinfection), even at negligible concentrations of residual disinfectant. The toxic effect of PAA on the aquatic environment was due to the residual disinfectant in the water, rather than to chemical modification of the effluent.

Bioaugmentation of flow-through sand filters

DEFF Research Database (Denmark)

Samuelsen, Elin Djurhuus

for degradation performances in flow-through sand columns, with the aim of identifying a suitable inoculant strain for future environmental applications. Another aim was to identify a suitable genetic marker to monitor phenoxy acid degradation in strain Sphingobium sp. PM2. We were not able to link motility...... and biofilm formation to the strains´ ability to adhere to sand. Nevertheless, a correlation was found between cell surface hydrophobicity and adhesion and overall degradation performances in flow-through sand columns. We identified S phingobium sp. PM2 as a promising inoculant strain, displaying efficient...... MCPA degradation for prolonged periods in flow-through sand columns. In an expression study of catabolic genes with putative roles in phenoxy acid degradation, we observed a marked upregulation of catabolic genes cadA and tfdC upon exposure to MCPA, 2,4-D, dichlorprop and mecoprop in strain PM2, which...

Cultivation of Azolla microphylla biomass on secondary-treated Delhi municipal effluents

Energy Technology Data Exchange (ETDEWEB)

Arora, A.; Saxena, S. [Indian Agricultural Research Institute, New Delhi (India). Centre for Conservation of Blue Green Algae

2005-07-01

Study was conducted on recycling municipal wastewaters for cultivation of Azolla microphylla biomass, which is used for inoculation into paddy fields as N biofertiliser and has other applications as green manure, animal feed and biofilter. Secondary-treated municipal wastewaters were collected from Wazirabad sewage treatment plant in New Delhi during all four seasons and tested for reactive P and heavy metal content. The reactive P levels in effluents ranged between 1-2 ppm and levels of heavy metals like Cd, Pb, Ni, Zn, Fe and Mn were well below permissible limits. A. microphylla was grown in sewage effluents and its dilutions prepared with tapwater. It showed good growth potential on sewage effluents. Doubling times during September and December months compared well with those on Espinase and Watanabe (E and W) medium and tapwater. Dried Azolla biomass produced on sewage waters did not show presence of toxic heavy metals Cd, Cr and Pb. However, levels of P in dried biomass cultivated on sewage effluents were lower as compared to those from E and W medium and tapwater. The biomass produced can be used for inoculating paddy fields or for other applications and polished wastewaters can be recycled for irrigation purposes. (author)

40 CFR 436.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Science.gov (United States)

2010-07-01

... Industrial Sand Subcategory § 436.42 Effluent limitations guidelines representing the degree of effluent... 6.0 and water quality criteria in water quality standards approved under the Act authorize such lower pH, the pH limitation for such discharge may be adjusted downward to the pH water quality...

A bio-anodic filter facilitated entrapment, decomposition and in situ oxidation of algal biomass in wastewater effluent.

Science.gov (United States)

Mohammadi Khalfbadam, Hassan; Cheng, Ka Yu; Sarukkalige, Ranjan; Kaksonen, Anna H; Kayaalp, Ahmet S; Ginige, Maneesha P

2016-09-01

This study examined for the first time the use of bioelectrochemical systems (BES) to entrap, decompose and oxidise fresh algal biomass from an algae-laden effluent. The experimental process consisted of a photobioreactor for a continuous production of the algal-laden effluent, and a two-chamber BES equipped with anodic graphite granules and carbon-felt to physically remove and oxidise algal biomass from the influent. Results showed that the BES filter could retain ca. 90% of the suspended solids (SS) loaded. A coulombic efficiency (CE) of 36.6% (based on particulate chemical oxygen demand (PCOD) removed) was achieved, which was consistent with the highest CEs of BES studies (operated in microbial fuel cell mode (MFC)) that included additional pre-treatment steps for algae hydrolysis. Overall, this study suggests that a filter type BES anode can effectively entrap, decompose and in situ oxidise algae without the need for a separate pre-treatment step. Copyright © 2016 Elsevier Ltd. All rights reserved.

Helmint eggs elimination performance during lammelar settling and sand filters in Beniel WWTP (Murcia, Spain)

International Nuclear Information System (INIS)

Simon Andreu, P. J.; Cardin Mifsut, C.; Pacheco Ballarin, S.; Martinez Muro, M. A.; Vicente Gonzalez, J. A.; Llosar Llacer, C.

2010-01-01

With this study, it was observed Ascaris suum eggs elimination yield of tertiary treatment in Beniel wastewater treatment plant (WWTP) in Murcia Region (Spain). It was inoculated a sample of Ascaris suum eggs in the treatment in maximum flow conditions and it was calculated the retention yield of the lamellar settling and sand filters. (Author) 3 refs.

Polishing of anaerobic secondary effluent by Chlorella vulgaris under low light intensity.

Science.gov (United States)

Cheng, Tuoyuan; Wei, Chun-Hai; Leiknes, TorOve

2017-10-01

To investigate anaerobic secondary effluent polishing by microalgae (Chlorella vulgaris) under low light intensity (14μmol/m 2 /s), bubbling column reactors were operated in batches of 8 d with initial ammonium nitrogen 10-50mg/L, initial phosphate phosphorus 2-10mg/L and microalgal seed 40mg/L. Maximum microalgal biomass and minimum generation time were 370.9mg/L and 2.5d, respectively. Nitrogen removal (maximum 99.6%) was mainly attributed to microalgal growth rate, while phosphorus removal (maximum 49.8%) was related to microalgal growth rate, cell phosphorus content (maximum 1.5%) and initial nutrients ratio. Dissolved microalgal organics release in terms of chemical oxygen demand (maximum 63.2mg/L) and hexane extractable material (i.e., oil and grease, maximum 8.5mg/L) was firstly reported and mainly affected by nitrogen deficiency and deteriorated effluent quality. Ultrafiltration critical flux (16.6-39.5L/m 2 /h) showed negative linear correlation to microalgal biomass. Anaerobic membrane bioreactor effluent polishing showed similar results with slight inhibition to synthetic effluent. Copyright © 2017 Elsevier Ltd. All rights reserved.

Density and distribution of nitrifying guilds in rapid sand filters for drinking water production: Dominance of Nitrospira spp

DEFF Research Database (Denmark)

Tatari, Karolina; Musovic, Sanin; Gülay, Arda

2017-01-01

distribution of these guilds, filter material was sampled at four drinking water treatment plants (DWTPs) in parallel filters of the pre- and after-filtration stages at different locations and depths. The target guilds were quantified by qPCR targeting 16S rRNA and amoA genes. Total bacterial densities......We investigated the density and distribution of total bacteria, canonical Ammonia Oxidizing Bacteria (AOB) (Nitrosomonas plus Nitrosospira), Ammonia Oxidizing Archaea (AOA), as well as Nitrobacter and Nitrospira in rapid sand filters used for groundwater treatment. To investigate the spatial...

40 CFR 141.550 - Is my system required to meet subpart T combined filter effluent turbidity limits?

Science.gov (United States)

2010-07-01

... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Enhanced Filtration and Disinfection-Systems Serving Fewer Than 10,000 People Combined Filter... utilize filtration other than slow sand filtration or diatomaceous earth filtration must meet the combined...

Effect of application rates and media types on nitrogen and surfactant removal in trickling filters applied to the post-treatment of effluents from UASB reactors

International Nuclear Information System (INIS)

Almeida, P. G. S. de; Taveres, F. v. F.; Chernicharo, C. A. I.

2009-01-01

Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)

Effect of application rates and media types on nitrogen and surfactant removal in trickling filters applied to the post-treatment of effluents from UASB reactors

Energy Technology Data Exchange (ETDEWEB)

Almeida, P. G. S. de; Taveres, F. v. F.; Chernicharo, C. A. I.

2009-07-01

Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)

Internal Porosity of Mineral Coating Supports Microbial Activity in Rapid Sand Filters for Groundwater Treatment

DEFF Research Database (Denmark)

Gülay, Arda; Tatari, Karolina; Musovic, Sanin

2014-01-01

of the filter material. The volumetric NH4+ removal rate also increased with the degree of mineral coating. Consistently, bacterial 16S rRNA and amoA abundances positively correlated with increased mineral coating levels. Microbial colonization could be visualized mainly within the outer periphery (60.6 ± 35......, and abundance of microbiota. This study reveals that a mineral coating can positively affect the colonization and activity of microbial communities in rapid sand filters. To understand this effect, we investigated the abundance, spatial distribution, colonization, and diversity of all and of nitrifying...... prokaryotes in filter material with various degrees of mineral coating. We also examined the physical and chemical characteristics of the mineral coating. The amount of mineral coating correlated positively with the internal porosity, the packed bulk density, and the biologically available surface area...

Performance test of filtering system for controlling the turbidity of secondary cooling water in HANARO

International Nuclear Information System (INIS)

Park, Y. C.; Woo, J. S.; Jo, Y. K.; Loo, J. S.; Lim, N. Y.

2001-01-01

There is about 80 m 3 /h loss of the secondary cooling water by evaporation, windage and blowdown during the operation of HANARO, 30 MW research reactor. When the secondary cooling water is treated by high Ca-hardness treatment program for minimizing the blowdown loss, only the trubidity exceeds the limit. By adding filtering system it was confirned, through the relation of turbidity and filtering rate of secondary cooling water, that the turbidity is reduced below the limit (5 deg.) by 2 % of filtering rate without blowdown. And it was verified, through the field performace test of filtering system under normal operation condition, that the circulation pumps get proper capacity and that filter units reduce the turbidity below the limit. Therefore, the secondary cooling water can be treated by the high Ca-hardness program and filter system without blowdown

Evaluating the effects of granular and membrane filtrations on chlorine demand in drinking water.

Science.gov (United States)

Jegatheesan, Veeriah; Kim, Seung Hyun; Joo, C K; Gao, Baoyu

2009-01-01

In this study, chlorine decay experiments were conducted for the raw water from Nakdong River that is treated by Chilseo Water Treatment Plant (CWTP) situated in Haman, Korea as well as the effluents from sand and granular activated carbon (GAC) filters of CWTP and fitted using a chlorine decay model. The model estimated the fast and slow reacting nitrogenous as well as organic/inorganic compounds that were present in the water. It was found that the chlorine demand due to fast and slow reacting (FRA and SRA) organic/inorganic substances was not reduced significantly by sand as well as GAC filters. However, the treated effluents from those filters contained FRA and SRA that are less reactive and had small reaction rate constants. For the effluents from microfiltration, ultrafiltration, and nanofiltration the chlorine demand because FRA and SRA were further reduced but the reaction rate constants were larger compared to those of sand and GAC filter effluents. This has implications in the formation of disinfection by products (DBPs). If DBPs are assumed to form due to the interactions between chlorine and SRA, then it is possible that the DBP formation potential in the effluents from membrane filtrations could be higher than that in the effluents from granular media filters.

Assessment of temporal and spatial evolution of bacterial communities in a biological sand filter mesocosm treating winery wastewater.

Science.gov (United States)

Ramond, J-B; Welz, P J; Tuffin, M I; Burton, S G; Cowan, D A

2013-07-01

To assess the impact of winery wastewater (WW) on biological sand filter (BSF) bacterial community structures, and to evaluate whether BSFs can constitute alternative and valuable treatment- processes to remediate WW. During 112 days, WW was used to contaminate a BSF mesocosm (length 173 cm/width 106 cm/depth 30 cm). The effect of WW on bacterial communities of four BSF microenvironments (surface/deep, inlet/outlet) was investigated using terminal-restriction fragment length polymorphism (T-RFLP). BSF achieved high Na (95·1%), complete Cl and almost complete chemical oxygen demand (COD) (98·0%) and phenolic (99·2%) removals. T-RFLP analysis combined with anosim revealed that WW significantly modified the surface and deep BSF bacterial communities. BSF provided high COD, phenolic and salt removals throughout the experiment. WW-selected bacterial communities were thus able to tolerate and/or degrade WW, suggesting that community composition does not alter BSF performances. However, biomass increased significantly in the WW-impacted surface sediments, which could later lead to system clogging and should thus be monitored. BSFs constitute alternatives to constructed wetlands to treat agri effluents such as WW. To our knowledge, this study is the first unravelling the responses of BSF bacterial communities to contamination and suggests that WW-selected BSF communities maintained high removal performances. Journal of Applied Microbiology © 2013 The Society for Applied Microbiology.

Development and optimization of a solid-phase microextraction gas chromatography-tandem mass spectrometry methodology to analyse ultraviolet filters in beach sand.

Science.gov (United States)

Vila, Marlene; Llompart, Maria; Garcia-Jares, Carmen; Homem, Vera; Dagnac, Thierry

2018-06-06

A methodology based on solid-phase microextraction (SPME) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) has been developed for the simultaneous analysis of eleven multiclass ultraviolet (UV) filters in beach sand. To the best of our knowledge, this is the first time that this extraction technique is applied to the analysis of UV filters in sand samples, and in other kind of environmental solid samples. Main extraction parameters such as the fibre coating, the amount of sample, the addition of salt, the volume of water added to the sand, and the temperature were optimized. An experimental design approach was implemented in order to find out the most favourable conditions. The final conditions consisted of adding 1 mL of water to 1 g of sample followed by the headspace SPME for 20 min at 100 °C, using PDMS/DVB as fibre coating. The SPME-GC-MS/MS method was validated in terms of linearity, accuracy, limits of detection and quantification, and precision. Recovery studies were also performed at three concentration levels in real Atlantic and Mediterranean sand samples. The recoveries were generally above 85% and relative standard deviations below 11%. The limits of detection were in the pg g -1 level. The validated methodology was successfully applied to the analysis of real sand samples collected from Atlantic Ocean beaches in the Northwest coast of Spain and Portugal, Canary Islands (Spain), and from Mediterranean Sea beaches in Mallorca Island (Spain). The most frequently found UV filters were ethylhexyl salicylate (EHS), homosalate (HMS), 4-methylbenzylidene camphor (4MBC), 2-ethylhexyl methoxycinnamate (2EHMC) and octocrylene (OCR), with concentrations up to 670 ng g -1 . Copyright © 2018 Elsevier B.V. All rights reserved.

Cold climate performance analysis of on-site domestic wastewater treatment systems.

Science.gov (United States)

Williamson, Eric

2010-06-01

Household on-site septic systems with secondary wastewater treatment in Anchorage, Alaska, were sampled and analyzed for performance parameters during the winter to spring months. System types included intermittent dosing sand filters (ISF), three types of recirculating trickling filters (RTF), and suspended-growth aeration tanks. Total nitrogen from the trickling filter and aeration tank effluent was fairly uniform, at approximately 30 mg/L. Total suspended solids (TSS) means were mostly less than 15 mg/L. The 5-day biochemical oxygen demand (BODs) showed considerable variability, with means ranging from 9.2 mg/ L for ISFs up to 39.5 mg/L for one type of RTF, even though this type has shown excellent results in several test programs. The data suggested that effluent temperature within the sample range had almost no effect on effluent concentrations of BOD5 or TSS and only a small effect on the removal of total nitrogen. Non-climatic factors were probably of equal importance to treatment results.

Performance evaluation and modelling studies of gravel--coir fibre--sand multimedia stormwater filter.

Science.gov (United States)

Samuel, Manoj P; Senthilvel, S; Tamilmani, D; Mathew, A C

2012-09-01

A horizontal flow multimedia stormwater filter was developed and tested for hydraulic efficiency and pollutant removal efficiency. Gravel, coconut (Cocos nucifera) fibre and sand were selected as the media and filled in 1:1:1 proportion. A fabric screen made up of woven sisal hemp was used to separate the media. The adsorption behaviour of coir fibre was determined in a series of column and batch studies and the corresponding isotherms were developed. The hydraulic efficiency of the filter showed a diminishing trend as the sediment level in inflow increased. The filter exhibited 100% sediment removal at lower sediment concentrations in inflow water (>6 g L(-1)). The filter could remove NO3(-), SO4(2-) and total solids (TS) effectively. Removal percentages of Mg(2+) and Na(+) were also found to be good. Similar results were obtained from a field evaluation study. Studies were also conducted to determine the pattern of silt and sediment deposition inside the filter body. The effects of residence time and rate of flow on removal percentages of NO3(-) and TS were also investigated out. In addition, a multiple regression equation that mathematically represents the filtration process was developed. Based on estimated annual costs and returns, all financial viability criteria (internal rate of return, net present value and benefit-cost ratio) were found favourable and affordable to farmers for investment in the developed filtration system. The model MUSIC was calibrated and validated for field conditions with respect to the developed stormwater filter.

Mimicking Retention and Transport of Rotavirus and Adenovirus in Sand Media Using DNA-labeled, Protein-coated Silica Nanoparticles

Science.gov (United States)

Pang, Liping; Farkas, Kata; Bennett, Grant; Varsani, Arvind; Easingwood, Richard; Tilley, Richard; Nowostawska, Urszula; Lin, Susan

2014-05-01

Rotavirus (RoV) and adenovirus (AdV) are important viral pathogens for the risk analysis of drinking water. Despite this, little is known about their retention and transport behaviors in porous media (e.g. sand filtered used for water treatment and groundwater aquifers due to a lack of representative surrogates. In this study, we developed RoV and AdV surrogates by covalently coating 70-nm sized silica nanoparticles with specific proteins and a DNA marker for sensitive detection. Filtration experiments using beach sand columns demonstrated the similarity of the surrogates' concentrations, attachment, and filtration efficiencies to the target viruses. The surrogates showed the same magnitude of concentration reduction as the viruses. Conversely, MS2 phage (a traditional virus model) over predicted concentrations of AdV and RoV by 1- and 2-orders of magnitude, respectively. The surrogates remained stable in size, surface charge and DNA concentration for at least one year. They can be easily and rapidly detected at concentrations down to one particle per PCR reaction and are readily detectable in natural waters and even in effluent. With up-scaling validation in pilot trials, the surrogates can be a useful cost-effective new tool for studying virus retention and transport in porous media, e.g. for assessing filter efficiency in water and wastewater treatment, tracking virus migration in groundwater after effluent land disposal, and establishing safe setback distances for groundwater protection.

CROSS-FLOW ULTRAFILTRATION OF SECONDARY EFFLUENTS. MEMBRANE FOULING ANALYSIS

Directory of Open Access Journals (Sweden)

Luisa Vera

2014-12-01

Full Text Available The application of cross-flow ultrafiltration to regenerate secondary effluents is limited by membrane fouling. This work analyzes the influence of the main operational parameters (transmembrane pressure and cross-flow velocity about the selectivity and fouling observed in an ultrafiltration tubular ceramic membrane. The experimental results have shown a significant retention of the microcolloidal and soluble organic matter (52 – 54% in the membrane. The fouling analysis has defined the critical operational conditions where the fouling resistance is minimized. Such conditions can be described in terms of a dimensionless number known as shear stress number and its relationship with other dimensionless parameter, the fouling number.

Bacterial nitrogen fixation in sand bioreactors treating winery wastewater with a high carbon to nitrogen ratio.

Science.gov (United States)

Welz, Pamela J; Ramond, Jean-Baptiste; Braun, Lorenz; Vikram, Surendra; Le Roes-Hill, Marilize

2018-02-01

Heterotrophic bacteria proliferate in organic-rich environments and systems containing sufficient essential nutrients. Nitrogen, phosphorus and potassium are the nutrients required in the highest concentrations. The ratio of carbon to nitrogen is an important consideration for wastewater bioremediation because insufficient nitrogen may result in decreased treatment efficiency. It has been shown that during the treatment of effluent from the pulp and paper industry, bacterial nitrogen fixation can supplement the nitrogen requirements of suspended growth systems. This study was conducted using physicochemical analyses and culture-dependent and -independent techniques to ascertain whether nitrogen-fixing bacteria were selected in biological sand filters used to treat synthetic winery wastewater with a high carbon to nitrogen ratio (193:1). The systems performed well, with the influent COD of 1351 mg/L being reduced by 84-89%. It was shown that the nitrogen fixing bacterial population was influenced by the presence of synthetic winery effluent in the surface layers of the biological sand filters, but not in the deeper layers. It was hypothesised that this was due to the greater availability of atmospheric nitrogen at the surface. The numbers of culture-able nitrogen-fixing bacteria, including presumptive Azotobacter spp. exhibited 1-2 log increases at the surface. The results of this study confirm that nitrogen fixation is an important mechanism to be considered during treatment of high carbon to nitrogen wastewater. If biological treatment systems can be operated to stimulate this phenomenon, it may obviate the need for nitrogen addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

A method for limiting sand production in wells

Energy Technology Data Exchange (ETDEWEB)

Smith, L M

1983-09-01

A method is patented which makes it possible to substantially limit sand falling into a well of an operational stratum which is made up of weakly cemented rocks. The presently known methods for controlling sand carry away into a well in the majority of cases provide for the installation in its bottom hole of a special filter. The winding of a sand and gravel filter is the most common. Serious problems associated with the difficulty in testing the winding process must be dealt with in this, as well as the use of additional equipment. The patented method lies in installing a specially made pipe filter in the bottom hole. The filtering element is the walls of the filter itself, which are made of a porous material. An important characteristic of the filter is the size of its pores which causes the filtration purity. The size of the pipe filter may be from 10 to 200 meters depending on the exploitation conditions.

Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2016-01-01

The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous......-flow lab-scale assay. NH4 + removal capacity, estimated from short term loading up-shifts, was at least 10 times higher in the top than in the middle and bottom filter layers, consistent with the stratification of Ammonium Oxidizing Bacteria (AOB). AOB density increased consistently with the NH4 + removal...... rate, indicating their primarily role in nitrification under the imposed experimental conditions. The maximum AOB cell specific NH4 + removal rate observed at the bottom was at least 3 times lower compared to the top and middle layers. Additionally, a significant up-shift capacity (4.6 and 3.5 times...

Hydrodynamic calculation of a filter sand bed type used in the containment venting systems; Calculo hidrodinamico de un filtro tipo lecho de arena usado en los sistemas de venteo de la contencion

Energy Technology Data Exchange (ETDEWEB)

Cuevas V, D.; Sainz M, E.; Ortiz V, J., E-mail: delfy.cu@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2015-09-15

The filtered venting of the containment has been adopted in European countries to mitigate the consequences of excess pressure containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter on the same path is placed, so that various types of filters are used to trap the fission products. The venting filters of the containment currently installed use different filtration technologies that involve more than one medium. Those using water as the first stage of filtration are called wet systems and are equipped with additional steps to remove water drops and fine aerosols emissions. And even they may also be equipped with an element containing certain absorption means for the filtration of gaseous iodine species. Other designs based on filtration of deep bed as the primary retention step; called dry filters, use filtration media of metal fiber, ceramic or sand to trap aerosols. This paper evaluates the hydraulic characteristics of the filter sand bed type designed by EDF as a candidate to be installed in the containment of BWR Mark II (type of primary containment of the nuclear power plant of Laguna Verde). The evaluation of filter sand bed type was performed using the software package of open source OpenFOAM. Models of each zone of the filtered device were generated and through a series of parametric calculations of computational fluid mechanics relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow rate and pressure fields and speed at different operating conditions. On the other hand, the model validation of the sand bed filter when comparing the results of experimental tests on a sand column of PITEAS program (1985-1986) against OpenFOAM simulation was realized. The results are very close to those obtained experimentally. (Author)

Performance evaluation of tertiary treatment through ultrafiltration: Case study in Isfahan-industrial wastewater treatment plant

Directory of Open Access Journals (Sweden)

Abbas Khodabakhshi

2015-01-01

Conclusion: UF was able to improve chemical parameters of secondary effluent and meet national environmental standards. However, achievement to optimum operation of this system requires adequate pretreatments such as adding filter aid, sand filtration and GAC. The most part of suspended particles expressed by turbidity was removed within UF membrane, whereas only a little of organic substance expressed by COD or color and salt expressed by conductivity could be removed.

Study on Modified Sand Filtration Towards Water Quality of Wet Market Waste Water

Directory of Open Access Journals (Sweden)

Saad F.N.M.

2016-01-01

Full Text Available Investigation on the potential of sand filter as a pre-treatment of waste water was done in Kangar wet market, Perlis. Besides, the best composition of filter in order to treat wastewater based on BOD, COD, SS, AN, turbidity and pH levels are further examined. In this study, there are four types of sand filter composition which the medias consist of fine sand and coarse sand while the modified sand filter are consist of sand, course sand and activated carbon prepared from rice husk and coconut shells. After 10 weeks of treatment, the results show that the concentration of BOD, COD, SS, AN, turbidity and pH were reduced up to 86%, 84%, 63%, 88%, 73%, respectively while pH nearly to neutral with 6.83. Moreover, the result also revealed that the sand filter added with rice husk almost complied with Standard B of Malaysia Environmental Quality (Sewage Regulations 2009 as well as gives the highest number of WQI with 36.81. Overall, WQI obtained in this study are ranged from 12.77 to 36.81.

Retention of radium from thermal waters on sand filters and adsorbents

Energy Technology Data Exchange (ETDEWEB)

Elejalde, C. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inpelsac@bi.ehu.es; Herranz, M. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Romero, F. [Dpto. de Ingenieria Quimica y del Medio Ambiente, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Baeza, A. [Dpto. de Fisica, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s/n, 10071 Caceres (Spain)

2007-06-18

This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research.

Retention of radium from thermal waters on sand filters and adsorbents

International Nuclear Information System (INIS)

Elejalde, C.; Herranz, M.; Idoeta, R.; Legarda, F.; Romero, F.; Baeza, A.

2007-01-01

This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research

Particle size distribution in effluent of trickling filters and in humus tanks.

Science.gov (United States)

Schubert, W; Günthert, F W

2001-11-01

Particles and aggregates from trickling filters must be eliminated from wastewater. Usually this happens through sedimentation in humus tanks. Investigations to characterize these solids by way of particle size measurements, image analysis and particle charge measurements (zeta potential) are made within the scope of Research Center for Science and Technology "Fundamentals of Aerobic biological wastewater treatment" (SFB 411). The particle size measuring results given within this report were obtained at the Ingolstadt wastewater treatment plant, Germany, which served as an example. They have been confirmed by similar results from other facilities. Particles flushed out from trickling filters will be partially destroyed on their way to the humus tank. A large amount of small particles is to be found there. On average 90% of the particles are smaller than 30 microm. Particle size plays a decisive role in the sedimentation behaviour of solids. Small particles need sedimentation times that cannot be provided in settling tanks. As a result they cause turbidity in the final effluent. Therefore quality of sewage discharge suffers, and there are hardly advantages of the fixed film reactor treatment compared to the activated sludge process regarding sedimentation behaviour.

Preliminary Study on Treatment of Palm Oil Mill Effluent (POME by Sand Filtration-DBD Plasma System

Directory of Open Access Journals (Sweden)

Ariadi Hazmi

2016-02-01

Full Text Available In the palm oil industry, open ponding, aerobic and anaerobic digestion, physicochemical treatment and membrane filtration are generally applied as conventional treatments of palm oil mill effluent (POME. In this study, a sand filtration-dielectric barrier discharge (DBD system was investigated as an alternative process for treating POME. This system can reduce land usage, processing time and costs compared to conventional systems. The removal efficiency of chemical oxygen demand (COD, biological oxygen demand (BOD5, and oil-grease in relation to the applied voltage were studied. Furthermore, the pH and temperature profiles were investigated. The obtained results indicate that the removal efficiency of COD, BOD5, and oil-grease increased with an increase of the applied voltage. The electrical energy consumption needed is about 10.56 kWh/L of POME.

Post-treatment and reuse of secondary effluents using natural ltreatment systems: the Indian practices.

Science.gov (United States)

Kumar, D; Asolekar, S R; Sharma, S K

2015-10-01

Paper summarizes the results of India-wide survey of natural treatment systems (NTSs) for wastewater treatment and reuse. The quality of treated wastewater from different types of NTSs was analyzed for various physico-chemical and bacteriological parameters, and needs for post-treatment were identified. Currently, about 1838 million liters per day (MLD) of wastewater is being treated using NTSs, of which the contributions of polishing ponds, waste stabilization ponds, duckweed ponds, constructed wetlands, and Karnal technology were found to be 53.39, 45.15, 0.13, 0.55, and 0.78%, respectively. Among the NTSs studied, constructed wetland was found most efficient in removal of pollutants including nitrogen, phosphorus, total coliform, and fecal coliform in the range of 76, 61, 99.956, and 99.923%, respectively. Of all types of NTSs, only constructed wetland was found to meet the total coliform count requirements (effluents for irrigation; effluents from 48 systems are being discharged into river or lake, and remaining 38 systems have not found any designated use of treated effluent. The chlorination was the only post-treatment, which is being practiced at only three wastewater treatment facilities. During post-treatment, 1-2 ppm of chlorine is applied to the secondary effluent irrespective of its quality. The treated effluents from different NTSs contain fecal bacteria in the magnitude of 10(3) to 10(5), which may cause the severe health impacts through contamination of groundwater as well as surface water resources.

Evaluation of secondary electron filter for removing contaminant electrons from high-energy 6 MV x-ray beam

International Nuclear Information System (INIS)

Kumagai, Kozo

1988-01-01

When using high energy X-rays, the dose increases at the skin surface and build-up region of beam contamination of secondary electrons coming out from the inner surface of the lineac head. At our radiotherapy department, many cases of external otitis from severe skin reactions, particularly resulting from whole brain irradiation of primary and metastatic brain tumors with a 6 MV X-ray lineac, have been encountered. An investigation was made of the physical aspects of a 6 MV X-ray beam using three electron filters, lead lucite, lead glass and lucite to remove secondary electrons. Transparent materials for filters should be preferable for locating the light field. The following results were obtained: 1) For removing secondary electrons, a lead lucite filter was found best. 2) The lead lucite filter proved most effective for removing secondary electrons from the area of treatment. It reduced the dose of irradiation to the skin surface and build-up region, and furthermore improved the depth dose relative to that without filters. 3) From a clinical standpoint, skin reactions such as external otitis remarkably decreased using a lead lucite filter. 4) It thus appears necessary to use a high energy X-ray with newly designed filters to reduce beam contamination of secondary electrons. (author)

Polishing of Anaerobic Secondary Effluent and Symbiotic Bioremediation of Raw Municipal Wastewater by Chlorella Vulgaris

KAUST Repository

Cheng, Tuoyuan

2016-05-01

To assess polishing of anaerobic secondary effluent and symbiotic bioremediation of primary effluent by microalgae, bench scale bubbling column reactors were operated in batch modes to test nutrients removal capacity and associated factors. Chemical oxygen demand (COD) together with oil and grease in terms of hexane extractable material (HEM) in the reactors were measured after batch cultivation tests of Chlorella Vulgaris, indicating the releasing algal metabolites were oleaginous (dissolved HEM up to 8.470 mg/L) and might hazard effluent quality. Ultrafiltration adopted as solid-liquid separation step was studied via critical flux and liquid chromatography-organic carbon detection (LC-OCD) analysis. Although nutrients removal was dominated by algal assimilation, nitrogen removal (99.6% maximum) was affected by generation time (2.49 days minimum) instead of specific nitrogen removal rate (sN, 20.72% maximum), while phosphorus removal (49.83% maximum) was related to both generation time and specific phosphorus removal rate (sP, 1.50% maximum). COD increase was affected by cell concentration (370.90 mg/L maximum), specific COD change rate (sCOD, 0.87 maximum) and shading effect. sCOD results implied algal metabolic pathway shift under nutrients stress, generally from lipid accumulation to starch accumulation when phosphorus lower than 5 mg/L, while HEM for batches with initial nitrogen of 10 mg/L implied this threshold around 8 mg/L. HEM and COD results implied algal metabolic pathway shift under nutrients stress. Anaerobic membrane bioreactor effluent polishing showed similar results to synthetic anaerobic secondary effluent with slight inhibition while 4 symbiotic bioremediation of raw municipal wastewater with microalgae and activated sludge showed competition for ammonium together with precipitation or microalgal luxury uptake of phosphorus. Critical flux was governed by algal cell concentration for ultrafiltration membrane with pore size of 30 nm, while

Polishing of municipal secondary effluent using native microalgae consortia.

Science.gov (United States)

Beltrán-Rocha, Julio César; Barceló-Quintal, Icela Dagmar; García-Martínez, Magdalena; Osornio-Berthet, Luis; Saavedra-Villarreal, Nidia; Villarreal-Chiu, Juan; López-Chuken, Ulrico Javier

2017-04-01

This work evaluates the use of native microalgae consortia for a dual role: polishing treatment of municipal wastewater effluents and microalgae biomass feedstock potential for biodiesel or biofertilizer production. An initial screening was undertaken to test N and P removal from secondary effluents and biomass production by 12 consortia. A subsequent treatment was performed by selected consortia (01 and 12) under three operational conditions: stirring (S), S + 12 h of daily aeration (S + A) and S + A enriched with CO 2 (S + AC). All treatments resulted in compliance with environmental regulations (e.g. Directive 91/271/EEC) and high removal efficiency of nutrients: 64-79% and 80-94% of total N and PO 4 3- -P respectively. During the experiments it was shown that pH alkalinization due to microalgae growth benefits the chemical removal of ammonia and phosphorus. Moreover, advantages of pH increase could be accomplished by intermittent CO 2 addition which in this research (treatment S + AC) promoted higher yield and lipid concentration. The resulting dry biomass analysis showed a low lipid content (0.5-4.3%) not ideal for biodiesel production. Moreover, the high rate of ash (29.3-53.0%) suggests that biomass could be readily recycled as a biofertilizer due to mineral supply and organic constituents formed by C, N and P (e.g. carbohydrate, protein, and lipids).

Rain events and their effect on effluent quality studied at a full scale activated sludge treatment plant.

Science.gov (United States)

Wilén, B M; Lumley, D; Mattsson, A; Mino, T

2006-01-01

The effect of rain events on effluent quality dynamics was studied at a full scale activated sludge wastewater treatment plant which has a process solution incorporating pre-denitrification in activated sludge with post-nitrification in trickling filters. The incoming wastewater flow varies significantly due to a combined sewer system. Changed flow conditions have an impact on the whole treatment process since the recirculation to the trickling filters is set by the hydraulic limitations of the secondary settlers. Apart from causing different hydraulic conditions in the plant, increased flow due to rain or snow-melting, changes the properties of the incoming wastewater which affects process performance and effluent quality, especially the particle removal efficiency. A comprehensive set of on-line and laboratory data were collected and analysed to assess the impact of rain events on the plant performance.

Analysis of the implementation of a sand bed type filter for the venting of a nuclear power plant; Analisis de la implementacion de un filtro tipo lecho de arena para el venteo de una central nuclear

Energy Technology Data Exchange (ETDEWEB)

Cuevas V, D.; Sainz M, E.; Ortiz V, J., E-mail: delfy.cu@gmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

2017-09-15

The filtered venting of the containment has been adopted in European countries to mitigate the consequences derived from the excess pressure of the containment during a severe accident. When venting has taken place, the fission products are released directly into the environment, unless a filter is placed in the path of the same, so various types of filters are used to trap the fission products. The containment venting filters currently installed use different filtering technologies that involve more than one medium. Those who use water as the first stage of filtration are called wet systems, are equipped with additional stages to eliminate water drops and emissions of fine aerosols, and may even be equipped with an element that contains certain means of absorption for the gaseous iodine species filtration. Other designs, based on deep bed filtration as the main retention stage, called dry filters; use metal fiber, ceramic or sand filtration media to trap aerosols. The present work evaluates the hydraulic characteristics of the sand bed type filter designed by EDF as a candidate to be installed in the containment of the BWR Mark II (primary containment type of the Laguna Verde nuclear power plant). The evaluation of the sand bed filter was performed using the OpenFOAM open source software package. Models of each zone of the filtering device were generated and by means of a series of parametric calculations of computational fluid mechanics, the relevant hydrodynamic characteristics of the device were obtained, such as pressure drops against mass flow and pressure fields and velocity under different operating conditions. On the other hand, the validation of the sand bed filter model was made when comparing the results of experimental tests carried out in a sand column of the PITEAS program (1985-1986) against the simulation in OpenFOAM. The results obtained are very close to those obtained experimentally. (Author)

Development and modelling of a steel slag filter effluent neutralization process with CO2-enriched air from an upstream bioprocess.

Science.gov (United States)

Bove, Patricia; Claveau-Mallet, Dominique; Boutet, Étienne; Lida, Félix; Comeau, Yves

2018-02-01

The main objective of this project was to develop a steel slag filter effluent neutralization process by acidification with CO 2 -enriched air coming from a bioprocess. Sub-objectives were to evaluate the neutralization capacity of different configurations of neutralization units in lab-scale conditions and to propose a design model of steel slag effluent neutralization. Two lab-scale column neutralization units fed with two different types of influent were operated at hydraulic retention time of 10 h. Tested variables were mode of flow (saturated or percolating), type of media (none, gravel, Bionest and AnoxKaldnes K3), type of air (ambient or CO 2 -enriched) and airflow rate. One neutralization field test (saturated and no media, 2000-5000 ppm CO 2 , sequential feeding, hydraulic retention time of 7.8 h) was conducted for 7 days. Lab-scale and field-scale tests resulted in effluent pH of 7.5-9.5 when the aeration rate was sufficiently high. A model was implemented in the PHREEQC software and was based on the carbonate system, CO 2 transfer and calcite precipitation; and was calibrated on ambient air lab tests. The model was validated with CO 2 -enriched air lab and field tests, providing satisfactory validation results over a wide range of CO 2 concentrations. The flow mode had a major impact on CO 2 transfer and hydraulic efficiency, while the type of media had little influence. The flow mode also had a major impact on the calcite surface concentration in the reactor: it was constant in saturated mode and was increasing in percolating mode. Predictions could be made for different steel slag effluent pH and different operation conditions (hydraulic retention time, CO 2 concentration, media and mode of flow). The pH of the steel slag filter effluent and the CO 2 concentration of the enriched air were factors that influenced most the effluent pH of the neutralization process. An increased concentration in CO 2 in the enriched air reduced calcite precipitation

Treatment and utilization of septic tank effluent using vertical-flow constructed wetlands and vegetable hydroponics.

Science.gov (United States)

Cui, Li-Hua; Luo, Shi-Ming; Zhu, Xi-Zhen; Liu, Ying-Hu

2003-01-01

Vertical flow constructed wetlands is a typical ecological sanitation system for sewage treatment. The removal rates for COD, BOD5, SS, TN, and TP were 60%, 80%, 74%, 49% and 79%, respectively, when septic tank effluent was treated by vertical flow filter. So the concentration of COD and BOD5 in the treated effluent could meet the quality standard for irrigation water. After that the treated effluent was used for hydroponic cultivation of water spinach and romaine lettuce, the removal efficiencies of the whole system for COD, BOD5, SS, TN and TP were 71.4%, 97.5%, 96.9%, 86.3%, and 87.4%, respectively. And it could meet the integrated wastewater discharge standard for secondary biological treatment plant. It was found that using treated effluent for hydroponic cultivation of vegetables could reduce the nitrate content in vegetables. The removal rates for total bacteria and coliform index by using vertical flow bed system with cinder substrate were 80%-90% and 85%-96%, respectively.

Backflushable filter experience at the N Reactor

International Nuclear Information System (INIS)

Ball, B.; Best, W.T.; Keith, R.C.

1987-01-01

The N Reactor is an 4000 MWt, light-water cooled, graphite-moderated reactor located on the Hanford Site in Washington State. A radwaste pilot plant to process plant effluent was constructed in order to maximize future efficiency when a full size radioactive processing facility is built. The pilot plant's purpose is to vary operational parameters such as filtration and ion exchange on a smaller scale to gather as much data as possible. The input to the pilot plant is radioactive drain lines from the N Reactor. The effluent passes through a backflushable filter and a series of ion exchange columns all scaled down from the future proposed facility. A backflushable filter was selected for this application because of the specific characteristics of the plant effluent and the potential reduced operating costs. The filter performance has been excellent in terms of filtration of the effluent. Typical total suspended solids in the plant effluent range from 1 to 6.1 ppm; the filter reduces this value to less than 0.1 ppm. In addition to outstanding filtration efficiency, the use of a precoat material on the filter has resulted in impressive decontamination factors. The filter has been successful in removing up to 50% of the influent activity. An improved performance of several nuclides over other filtration systems has also been achieved. By varying the composition and amount of precoat material on the filter, substantial reductions in waste volumes (and associated operating and disposal costs) have been demonstrated while maintaining a high degree of removal of both activity and total suspended solids

Secondary wastes and treatment of effluents from leaching of uranium from soils

International Nuclear Information System (INIS)

Ally, M.R.; Wilson, J.H.; Francis, C.W.

1993-01-01

The Department of Energy's Feed Materials and Production Center at Fernald, Ohio has over two million cubic meters of soil contaminated with Uranium which must be cleaned. Soil characterization studies show that Uranium is unevenly distributed between the clay, sand and silt fractions. This paper examines the option of using leaching agents to remove Uranium from the soil and the treatment of secondary wastes. Results of the effects of various leachants in removing Uranium and the complications of co-leaching minerals/organic matter that are important for maintaining soil integrity and structure shall be discussed. Candidate leachants must remove the Uranium level below 35pCi/g of soil and produce a secondary waste that is amenable to on-site treatment at reasonable cost

Sorption of europium by Haro river sand in aqueous solution

International Nuclear Information System (INIS)

Syed Moosa Hasany; Syed Javaid Khurshid

1997-01-01

The sorption of Eu(III) on Haro river sand has been investigated. Influences include composition of the sorptive medium, the concentration of sorbent and sorbate, and shaking time. Haro river sand can be exploited for the preconcentration and removal of europium from very dilute solutions, for the decontamination and treatment of radioactive waste water and effluents from nuclear installations. (Author)

Submerged Pond Sand Filter—A Novel Approach to Rural Water Supply

Directory of Open Access Journals (Sweden)

Mia Øhlenschlæger

2016-06-01

Full Text Available This study describes the new design and function of a modified version of a traditional slow sand filter. The Submerged Pond Sand Filter is built inside a pond and has a vertical as well as a horizontal flow of water through a sloped filter opening. The filter provides treated drinking water to a rural Indian village. The filter has functioned with minimal maintenance for five years without being subject to the typical scraping off and changing of sand as needed in traditional slow sand filters every few months. This five-year study showed bacterial removal efficiency of 97% on average with a level of faecal coliforms of 2 ± 2 colony forming units (CFU/100 mL measured in the treated water. Turbidity was visibly removed during treatment. When water was retrieved from the filter through a manual pump for long consistent time intervals (60 min, faecal coliform counts increased from four to 10 CFU/100 mL on average compared to shorter pumping intervals (5 min. Though the treated water did not comply with the World Health Organization standards of 0 CFU/100 mL, the filter significantly improved water quality and provided one of the best sources of drinkable water in a water-depleted area, where only surface water was available. Furthermore, it is a sustainable treatment method due to low maintenance requirements.

Effluent migration from septic tank systems in two different lithologies, Broward County, Florida

Science.gov (United States)

Waller, B.G.; Howie, Barbara; Causaras, C.R.

1987-01-01

Two septic tank test sites, one in sand and one in limestone, in Broward County, Florida, were analyzed for effluent migration. Groundwater from shallow wells, both in background areas and hydraulically down-gradient of the septic tank system, was sampled during a 16-month period from April 1983 through August 1984. Water quality indicators were used to determine the effluent affected zone near the septic tank systems. Specific conductance levels and concentrations of chloride, sulfate, ammonium, and nitrate indicated effluent movement primarily in a vertical direction with abrupt dilution as it moved down-gradient. Effluent was detected in the sand to a depth more than 20 ft below the septic tank outlet, but was diluted to near background conditions 50 ft down-gradient from the tank. Effluent in the limestone was detected in all three observation wells to depths exceeding 25 ft below the septic tank outlet and was diluted, but still detectable, 40 ft down-gradient. The primary controls on effluent movement from septic tank systems in Broward County are the lithology and layering of the geologic materials, hydraulic gradients, and the volume and type of use the system receives. (Author 's abstract)

Designing metallic iron based water filters: Light from methylene blue discoloration.

Science.gov (United States)

Btatkeu-K, B D; Tchatchueng, J B; Noubactep, C; Caré, S

2016-01-15

Available water filtration systems containing metallic iron (Fe(0) filters) are pragmatically designed. There is a lack of sound design criteria to exploit the full potential of Fe(0) filters. A science-based design relies on valuable information on processes within a Fe(0) filter, including chemical reactions, hydrodynamics and their relation to the performance of the filter. The aim of this study was to establish a simple method to evaluate the initial performance of Fe(0) filters. The differential adsorptive affinity of methylene blue (MB) onto sand and iron oxide is exploited to characterize the evolution of a Fe(0)/sand system using the pure sand system as operational reference. Five systems were investigated for more than 70 days: pure sand, pure Fe(0), Fe(0)/sand, Fe(0)/pumice and Fe(0)/sand/pumice. Individual systems were characterized by the extent of changes in pH value, iron breakthrough, MB breakthrough and hydraulic conductivity. Results showed that for MB discoloration (i) pure sand was the most efficient system, (ii) hybrid systems were more sustainable than the pure Fe(0) system, and (iii) the pores of used pumice are poorly interconnected. Characterizing the initial reactivity of Fe(0) filters using MB discoloration has introduced a powerful tool for the exploration of various aspects of filter design. Copyright © 2015 Elsevier Ltd. All rights reserved.

40 CFR 436.32 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Science.gov (United States)

2010-07-01

... Construction Sand and Gravel Subcategory § 436.32 Effluent limitations guidelines representing the degree of... unaltered by man's activities, is or would be less than 6.0 and water quality criteria in water quality... adjusted downward to the pH water quality criterion for the receiving waters. In no case shall a pH...

Sewage Effluent Infiltrates Frozen Forest Soil

Science.gov (United States)

Alfred Ray Harris

1976-01-01

Secondarily treated sewage effluent, applied at the rate of 1 and 2 inches per week, infiltrated a frozen Sparta sand soil forested with jack pine and scrub oak. Maximum frost depth in treated plots averaged 60 cm and in check plots averages 35 cm. Nitrogen was mobile with some accumulation. Phosphorus was absorbed.

Ambiance rose production and nutrient supply in soil irrigated with treated sewage

Directory of Open Access Journals (Sweden)

Giuliano Gabrielli

2015-08-01

Full Text Available ABSTRACTEffluents from secondary sewage treatment plants may contain amount of nutrients with the potential to cause eutrophication of water bodies. One of the ways to decrease this influx of nutrients would be the agricultural reuse. Therefore, the objective of this study was to evaluate the irrigation of roses of the Ambiance variety with the effluent from an anaerobic reactor and an intermittent sand filter (nitrified effluent. The trial lasted for 152 days. The dose of nitrogen applied via effluent was 91% of the crop requirement; of phosphorus, 3.5% (very low; and of potassium, 23%. There was no difference among treatments for the evaluated variables: diameter and length of stem, diameter and length of bud, and fresh weight of flower buds. The production of floral stems was higher in treatments with effluents without conventional fertilization. It is concluded that the irrigation with a treated effluent is an alternative for the fertilization of ambiance roses.

Bacterial treatment effectiveness of point-of-use ceramic water filters.

Science.gov (United States)

Bielefeldt, Angela R; Kowalski, Kate; Summers, R Scott

2009-08-01

Laboratory experiments were conducted on six point-of-use (POU) ceramic water filters that were manufactured in Nicaragua; two filters were used by families for ca. 4 years and the other filters had limited prior use in our lab. Water spiked with ca. 10(6)CFU/mL of Escherichia coli was dosed to the filters. Initial disinfection efficiencies ranged from 3 - 4.5 log, but the treatment efficiency decreased with subsequent batches of spiked water. Silver concentrations in the effluent water ranged from 0.04 - 1.75 ppb. Subsequent experiments that utilized feed water without a bacterial spike yielded 10(3)-10(5)CFU/mL bacteria in the effluent. Immediately after recoating four of the filters with a colloidal silver solution, the effluent silver concentrations increased to 36 - 45 ppb and bacterial disinfection efficiencies were 3.8-4.5 log. The treatment effectiveness decreased to 0.2 - 2.5 log after loading multiple batches of highly contaminated water. In subsequent loading of clean water, the effluent water contained filters. This indicates that the silver had some benefit to reducing bacterial contamination by the filter. In general these POU filters were found to be effective, but showed loss of effectiveness with time and indicated a release of microbes into subsequent volumes of water passed through the system.

Processo da retrolavagem em filtros de areia usados na irrigação localizada Backwash process in sand filters used in localized irrigation

Directory of Open Access Journals (Sweden)

Juan C Salcedo

2011-12-01

Full Text Available O processo da retrolavagem consiste na passagem da água através do filtro em sentido contrário ao fluxo de filtragem com o objetivo de remover partículas orgânicas e inorgânicas retidas no meio filtrante. O projeto de filtros de areia com configurações ineficientes e a ocorrência de condições operacionais inadequadas contribuem para limitar o desempenho desse processo, causando deficiências na limpeza dos meios filtrantes e comprometendo o funcionamento dos sistemas de irrigação localizada. O objetivo do presente trabalho é proporcionar uma revisão sobre os conceitos associados ao processo da retrolavagem nos filtros de areia, relacionando informações existentes na literatura com experiências de laboratório. Foi gerado um texto básico com informações técnico-científicas sobre o tema, visando a criar um momento de reflexão sobre o processo de retrolavagem e a contribuir para a melhoria do desempenho desses equipamentos na irrigação localizada.The backwash process consists of water passing through the filter in the opposite direction of the filtering flow to remove organic and inorganic particles of media filter. Inefficient sand filters designs and the occurrence of inadequate operating conditions contribute to restrict the process performance, causing deficiencies in the filter cleaning and compromise the operation of localized irrigation systems. The objective of this study is to provide a review about concepts associated with the backwash process in sand filters, relating literature information with laboratory experiments. A basic documentation was produced with technical and scientific information on this subject to create a reflection about the backwash process and contribute to the improvement of the equipment performance in the localized irrigation.

Membrane Fouling Potential of Secondary Effluent Organic Matter (EfOM) from Conventional Activated Sludge Process

KAUST Repository

Wei, Chunhai; Amy, Gary L.

2012-01-01

Secondary effluent organic matter (EfOM) from a conventional activated sludge process was filtered through constant-pressure dead-end filtration tests with a sequential ultrafiltration (UF, molecular weight cut-off (MWCO) of 10k Dalton) and nanofiltration (NF, MWCO of 200 Dalton) array to investigate its membrane fouling potential. Advanced analytical methods including liquid chromatography with online carbon detection (LC-OCD) and fluorescent excitation-emission matrix (F-EEM) were employed for EfOM characterization. EfOM consisted of humic substances and building blocks, low molecular weight (LMW) neutrals, biopolymers (mainly proteins) and hydrophobic organics according to the sequence of their organic carbon fractions. The UF rejected only biopolymers and the NF rejected most humics and building blocks and a significant part of LMW neutrals. Simultaneous occurrence of cake layer and standard blocking during the filtration process of both UF and NF was identified according to constant-pressure filtration equations, which was possibly caused by the heterogeneous nature of EfOM with a wide MW distribution (several ten to several million Dalton). Thus the corresponding two fouling indices (kc for cake layer and ks for standard blocking) from UF and NF could characterize the fouling potential of macromolecular biopolymers and low to intermediate MW organics (including humics, building blocks, LMW neutrals), respectively. Compared with macromolecular biopolymers, low to intermediate MW organics exhibited a much higher fouling potential due to their lower molecular weight and higher concentration.

Geo synthetics in hydraulic and coastal engineering: Filters, revetments and sand filled structures; Geosinteticos en ingenieria hidraulica y costera: filtros, revestimientos y estructuras llenas de arena

Energy Technology Data Exchange (ETDEWEB)

Bezuijen, A.; Pilarczyk, K. W.

2014-02-01

The paper deals with 2 applications of geo textiles in coastal and hydraulic engineering: Geo textiles in filters and revetments; and geo textiles in sand filled structure. Geo textiles are often replacing granular filters. However, they have different properties than a granular filter. For the application of geo textiles in revetments, the consequences of the different properties will be shown: how permeability is influenced by a geo textile and what can be the consequences of the weight differences between granular and geo textile filters. In the other application, the filter properties of geo textiles are only secondary. In geo textile tubes and containers the geo textile is used as wrapping material to create large unties that will not erode during wave attach. the structures with geo textile tubes and containers serve as an alternative for rock based structures. The first of these structures were more or less constructed by trial and error, but research on the shape of the structures, the stability under wave attach and the durability of the used of the used material has given the possibility to use design tools for these structures. Recently also the morphological aspects of these structures have been investigated. This is of importance because regularly structures with geo textile tubes fail due to insufficient toe protection against the scour hole that that develops in front of the structure, leading to undermining of the structure. Recent research in the Dealt Flume of Deltares and the Large Wave Flume in Hannover has led to better understanding what mechanisms determine the stability under wave attach. It is shown that also the degree of filling is of importance and the position of the water level with respect to the tube has a large influence. (Author)

Treatment of secondary effluent by sequential combination of photocatalytic oxidation with ceramic membrane filtration.

Science.gov (United States)

Song, Lili; Zhu, Bo; Jegatheesan, Veeriah; Gray, Stephen; Duke, Mikel; Muthukumaran, Shobha

2018-02-01

The aim of the present work was to experimentally evaluate an alternative advanced wastewater treatment system, which combines the action of photocatalytic oxidation with ceramic membrane filtration. Experiments were carried out using laboratory scale TiO 2 /UV photocatalytic reactor and tubular ceramic microfiltration (CMF) system to treat the secondary effluent (SE). A 100-nm pore size CMF membrane was investigated in cross flow mode under constant transmembrane pressure of 20 kPa. The results show that specific flux decline of CMF membrane with and without TiO 2 /UV photocatalytic treatment was 30 and 50%, respectively, after 60 min of filtration. Data evaluation revealed that the adsorption of organic compounds onto the TiO 2 particles was dependent on the pH of the suspension and was considerably higher at low pH. The liquid chromatography-organic carbon detector (LC-OCD) technique was used to characterise the dissolved organic matter (DOM) present in the SE and was monitored following photocatalysis and CMF. The results showed that there was no removal of biopolymers and slight removal of humics, building blocks and the other oxidation by-products after TiO 2 /UV photocatalytic treatment. This result suggested that the various ions present in the SE act as scavengers, which considerably decrease the efficiency of the photocatalytic oxidation reactions. On the other hand, the CMF was effective for removing 50% of biopolymers with no further removal of other organic components after photocatalytic treatment. Thus, the quantity of biopolymers in SE has an apparent correlation with the filterability of water samples in CMF.

Study of Slow Sand Filtration in Removing Total Coliforms and E.Coli

Directory of Open Access Journals (Sweden)

Ekha Yogafanny

2015-08-01

Full Text Available This study was aimed to evaluate the performance of SSF in removing bacteria (Total Coliforms and E. Coli in regard to grain size distribution and grain shape intermittently. Two methodological approaches used in this reasearch were literature review and laboratory work. Bacteria removal was analyzed considering two different filter media (Rhine sand-spherical shape and Lava sand-angular shape with three different grain size distributions. The best performance was attained by filter column F4 which consisted of Lava sand and had the configuration C2 (d10 = 0.07 mm; Cu = 4.2. This filter column achieved 4.7log-units removal of Total Coliforms and 5.0log-units removal of E. coli. The results show that a smaller grain size and an angular shape of sand grain lead to an increase in bacteria removal.

Analysis of chemical reaction kinetics of depredating organic pollutants from secondary effluent of wastewater treatment plant in constructed wetlands.

Science.gov (United States)

Wang, Hao; Jiang, Dengling; Yang, Yong; Cao, Guoping

2013-01-01

Four subsurface constructed wetlands were built to treat the secondary effluent of a wastewater treatment plant in Tangshan, China. The chemical pollutant indexes of chemical oxygen demand (COD) were analyzed to evaluate the removal efficiency of organic pollutants from the secondary effluent of the wastewater treatment plant. In all cases, the subsurface constructed wetlands were efficient in treating organic pollutants. Under the same hydraulic loading condition, the horizontal flow wetlands exhibited better efficiency of COD removal than vertical flow wetlands: the removal rates in horizontal flow wetlands could be maintained at 68.4 ± 2.42% to 92.2 ± 1.61%, compared with 63.8 ± 1.19% to 85.0 ± 1.25% in the vertical flow wetlands. Meanwhile, the chemical reaction kinetics of organic pollutants was analyzed, and the results showed that the degradation courses of the four subsurface wetlands all corresponded with the first order reaction kinetics to a large extent.

Investigation of TC and TSS Removal Efficiencies at Ahvaz West WTP Effluent Using the Land‒plant Treatment Process

Directory of Open Access Journals (Sweden)

Afshin Takdastan

2015-12-01

Full Text Available Although the conventional (primary and secondary treatment processes are known to remove up to 95–99% of some micro-organisms, they do not provide adequate treatment to make the effluent suitable for direct reuse, mainly due to the presence of high concentrations of pathogenic microorganisms. Obtaining reusable effluents, therefore, requires the use of processes that can be justified both technical and economic grounds. One such indigenous, low cost option is the land-plant process that can be used for advanced wastewater treatment. It is the objective of the present study to determine the efficiency of the local soil in Ahvaz and that of the vetiver plant in reducing the microbial load in the effluent from municipal wastewater treatment plants. A pilot study was thus carried out including three Lysimeters installed in West Ahvaz Wastewater Treatment Plant. Local soil was used in one Lysimeter, local soil with vetiver plant in the second one, and an artificial assortment of soil comprising local soil, silica sand (0.5-1mm, and sand (15-30mm in the third. In addition, the effluent from the secondary settling outlet at the WTP was transferred by pumping at the three filtration rates of 0.2, 0.6, and 1 ml/min into the system with three replications for each rate and samples were collected from both inlet and outlet flows. The average removal efficiencies of Total Suspended Solids (TSS and Total Coliform (TC in the effluent from the three Lysimeters with local soil with vetiver, local soil without vetiver, and artificial soil assortment for the filtration rate of 0.2 ml/min were: 67.75% and 99.7%, 58.33% and 99.6%, and 56.25% and 99.5%, respectively. For a filtration rate of 0.6 ml/min, these values were: 53.33% and 98.93%, 48.8 and 98.77%, and 47.68% and 98.64%. Finally, the values obtained for a filtration rate of 0.6 ml/min were: 50% and 93.96%, 46.42 and 91.34%, and 44/04% and 88/81%, respectively. The results from the study showed that the

Preliminary results for filtering-ecosystems in Val Trebbia (PC - Italy); Primi risultati per gli ecosistemi-filtro della Val Trebbia (PC)

Energy Technology Data Exchange (ETDEWEB)

Malcevschi, Sergio [Pavia, Univ. (Italy). Dipt. di Biologia Animale; Bisogni, G Luca [N.Q.A. s.r.l., Pavia (Italy); Bernini, Fabrizio [Amministrazione Provinciale di Piacenza, Piacenza (Italy)

1997-09-01

Some artificial wetlands were constructed in 1993-1994 in the Trebbia Valley (Piacenza, Italy). These plants worked as further treatment of secondary effluents of five little towns in the valley: Bobbio, Travo, Perino-Dolgo, Marsaglia, Ottone. The project and the realization considered the systems as Filtering Ecosystems and not a simple Aquatic Plant Systems. In 1994-1995 a research by University of Pavia was carried out, on the filtering ecosystem of Bobbio. Removal efficiency was 9,9 for phaecal coliforms, and 65% for nitrates.

Performance of water filters towards the removal of selected ...

African Journals Online (AJOL)

Organic matter removal was found to be 47%, 43%, 53%, 43.4% for bio-sand, slow sand, ceramic and membrane purifier respectively, while, fluoride removal was found to be 95.5% for bone char filter. Furthermore, filters were also assessed in terms of media availability, buying costs, operation, benefits/ effectiveness ...

Continuous monitoring of gaseous effluents

International Nuclear Information System (INIS)

Velasco, A.; Giraut, H.; Prado, M.; Bonino, A.D.

1990-01-01

The system allows to continuously determine the radioactive materials discharge (iodine, noble gases and aerosols) to the environment. It consists in compelling, by a pump, a known and fixed fraction of the total flow and preserving the aerosols by a filter. The gas -now free from aerosols- traverses an activated carbon filter which keeps the iodine; after being free from aerosols and iodine, the effluent traverses a measurement chambers for noble gases which has a scintillator. (Author) [es

Primary effluent filtration for coastal discharges

Energy Technology Data Exchange (ETDEWEB)

Cooper-Smith, G.D. [Yorkshire Water Services, Huddersfield (United Kingdom); Rundle, H. [The Capital Controls Group, Nottingham (United Kingdom)

1998-12-31

The use of a Tetra Deep Bed filter demonstration unit to treat primary effluent (Primary Effluent Filtration, PEF) was investigated. PEF proved capable of achieving the UWWTD primary standard, even when the primary stage performs poorly, but is not a cost-effective alternative to chemically assisted settlement. Results demonstrated that using a 1.5 to 2.2 mm grade medium, a filtration rate of 5 m/h, three backwashes a day and dosing 40 mg/l of PAXXL60 (a polyaluminium silicte) an average effluent quality of 20 mg/l BOD and 15 mgl/l total solid could be achieved. UV disinfection produced an effluent which complied with the Bathing Water Directive imperative requirement. A high enterovirus kill was also achieved. However, considerable additional work would be required before PEF could be considered suitable for full-scale applications. (orig.)

Bacterial, viral and turbidity removal by intermittent slow sand filtration for household use in developing countries: experimental investigation and modeling.

Science.gov (United States)

Jenkins, Marion W; Tiwari, Sangam K; Darby, Jeannie

2011-11-15

A two-factor three-block experimental design was developed to permit rigorous evaluation and modeling of the main effects and interactions of sand size (d(10) of 0.17 and 0.52 mm) and hydraulic head (10, 20, and 30 cm) on removal of fecal coliform (FC) bacteria, MS2 bacteriophage virus, and turbidity, under two batch operating modes ('long' and 'short') in intermittent slow sand filters (ISSFs). Long operation involved an overnight pause time between feeding of two successive 20 L batches (16 h average batch residence time (RT)). Short operation involved no pause between two 20 L batch feeds (5h average batch RT). Conditions tested were representative of those encountered in developing country field settings. Over a ten week period, the 18 experimental filters were fed river water augmented with wastewater (influent turbidity of 5.4-58.6 NTU) and maintained with the wet harrowing method. Linear mixed modeling allowed systematic estimates of the independent marginal effects of each independent variable on each performance outcome of interest while controlling for the effects of variations in a batch's actual residence time, days since maintenance, and influent turbidity. This is the first study in which simultaneous measurement of bacteria, viruses and turbidity removal at the batch level over an extended duration has been undertaken with a large number of replicate units to permit rigorous modeling of ISSF performance variability within and across a range of likely filter design configurations and operating conditions. On average, the experimental filters removed 1.40 log fecal coliform CFU (SD 0.40 log, N=249), 0.54 log MS2 PFU (SD 0.42 log, N=245) and 89.0 percent turbidity (SD 6.9 percent, N=263). Effluent turbidity averaged 1.24 NTU (SD 0.53 NTU, N=263) and always remained below 3 NTU. Under the best performing design configuration and operating mode (fine sand, 10 cm head, long operation, initial HLR of 0.01-0.03 m/h), mean 1.82 log removal of bacteria (98

Ecotoxicological impacts of effluents generated by oil sands bitumen extraction and oil sands lixiviation on Pseudokirchneriella subcapitata

Energy Technology Data Exchange (ETDEWEB)

Debenest, T., E-mail: tdebenest@yahoo.fr [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Turcotte, P. [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Gagne, F., E-mail: francois.gagne@ec.gc.ca [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada); Gagnon, C.; Blaise, C. [Environment Canada, Fluvial Ecosystem Research, 105 McGill Street, 7 floor, Montreal, Quebec, H2Y 2E7 (Canada)

2012-05-15

The exploitation of Athabasca oil sands deposits in northern Alberta has known an intense development in recent years. This development has raised concern about the ecotoxicological risk of such industrial activities adjacent to the Athabasca River. Indeed, bitumen extraction generated large amounts of oil sands process-affected water (OSPW) which are discharged in tailing ponds in the Athabasca River watershed. This study sought to evaluate and compare the toxicity of OSPW and oil sands lixiviate water (OSLW) with a baseline (oil sands exposed to water; OSW) on a microalgae, Pseudokirchneriella subcapitata, at different concentrations (1.9, 5.5, 12.25, 25 and 37.5%, v/v). Chemical analyses of water-soluble contaminants showed that OSPW and OSLW were enriched in different elements such as vanadium (enrichment factor, EF = 66 and 12, respectively), aluminum (EF = 64 and 15, respectively), iron (EF = 52.5 and 17.1, respectively) and chromium (39 and 10, respectively). The toxicity of OSPW on cells with optimal intracellular esterase activity and chlorophyll autofluorescence (viable cells) (72 h-IC 50% < 1.9%) was 20 times higher than the one of OSW (72 h-IC 50% > 37.5%, v/v). OSLW was 4.4 times less toxic (IC 50% = 8.5%, v/v) than OSPW and 4.5 times more toxic than OSW. The inhibition of viable cell growth was significantly and highly correlated (<-0.7) with the increase of arsenic, beryllium, chromium, copper, lead, molybdenum and vanadium concentrations. The specific photosynthetic responses studied with JIP-test (rapid and polyphasic chlorophyll a fluorescence emission) showed a stimulation of the different functional parameters (efficiency of PSII to absorb energy from photons, size of effective PSII antenna and vitality of photosynthetic apparatus for energy conversion) in cultures exposed to OSPW and OSLW. To our knowledge, our study highlights the first evidence of physiological effects of OSPW and OSLW on microalgae.

Palm oil mill effluent treatment using a two-stage microbial fuel cells system integrated with immobilized biological aerated filters.

Science.gov (United States)

Cheng, Jia; Zhu, Xiuping; Ni, Jinren; Borthwick, Alistair

2010-04-01

An integrated system of two-stage microbial fuel cells (MFCs) and immobilized biological aerated filters (I-BAFs) was used to treat palm oil mill effluent (POME) at laboratory scale. By replacing the conventional two-stage up-flow anaerobic sludge blanket (UASB) with a newly proposed upflow membrane-less microbial fuel cell (UML-MFC) in the integrated system, significant improvements on NH(3)-N removal were observed and direct electricity generation implemented in both MFC1 and MFC2. Moreover, the coupled iron-carbon micro-electrolysis in the cathode of MFC2 further enhanced treatment efficiency of organic compounds. The I-BAFs played a major role in further removal of NH(3)-N and COD. For influent COD and NH(3)-N of 10,000 and 125 mg/L, respectively, the final effluents COD and NH(3)-N were below 350 and 8 mg/L, with removal rates higher than 96.5% and 93.6%. The GC-MS analysis indicated that most of the contaminants were satisfactorily biodegraded by the integrated system. Copyright 2009 Elsevier Ltd. All rights reserved.

40 CFR 421.223 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Science.gov (United States)

2010-07-01

...) Vanadium decomposition wet air pollution control. BAT Limitations for the Secondary Molybdenum and Vanadium... (d) Molybdenum drying wet air pollution control. BAT Limitations for the Secondary Molybdenum and... representing the degree of effluent reduction attainable by the application of the best available technology...

Dust filtration on a panel bed of sand

International Nuclear Information System (INIS)

Goossens, W.R.A.; Francesconi, A.; Dumont, G.; Harnie, R.

1976-01-01

The development of a panel bed of sand as dust filter is described. The results obtained in a technical set-up with a filtering area of 1 m 2 are given. The data of a 2 4 factorial design experimental campaign are presented in the form of the resulting statistical equation

Peat wetland as a natural filter of effluents from adjacent industrial areas

Directory of Open Access Journals (Sweden)

József DEZSO

2015-12-01

Full Text Available The main objective of the project is the study of a peat wetland functioning as recipient of effluents from former and present-day industrial activities. The investigation was focused on heavy metal contaminations and their probable mobilization or fixation. The studied peatbog is a typical Eastern European wetland, located in Hungary on the border between medium mountains (Bakony Mountains and a Neogene basin (the Sárrét, an area under nature conservation. Watercourses and prevailing air currents can transport contaminants from industrial areas to the wetland. At first the basic parameters of surface waters and subsurface conditions (soils, groundwater were investigated. These parameters (EC, Cl are possible indicators of contamination. Subsequently, the amounts of heavy metals (Cd, Pb extracted by solution in two steps (HCl, CaCl2 were measured using atomic absorption spectroscopy (AAS. The extracted values indicate what amounts of which elements could be mobilized by human impact and/or production of humic acids, which occasionally emerges during the remediation works. The total heavy metal concentrations in the samples were investigated by X-ray fluorescence method. Based on the investigation, the peatbog is claimed to function as a natural filter.

Physical factors related to the marine disposal of industrial effluents off Pondicherry

Digital Repository Service at National Institute of Oceanography (India)

Swamy, G.N.; Vijayakumar, C.V.; Govindan, K.; Desai, B.N.

the nearshore bed was mostly composed of sand. Dye-diffusion studies showed that the waters off Pondicherry proper were less turbulent than those off Pilliarkuppam. The results are discussed in the context of locating effluent outlets...

A hybrid process of biofiltration of secondary effluent followed by ozonation and short soil aquifer treatment for water reuse.

Science.gov (United States)

Zucker, I; Mamane, H; Cikurel, H; Jekel, M; Hübner, U; Avisar, D

2015-11-01

The Shafdan reclamation project facility (Tel Aviv, Israel) practices soil aquifer treatment (SAT) of secondary effluent with hydraulic retention times (HRTs) of a few months to a year for unrestricted agricultural irrigation. During the SAT, the high oxygen demand (>40 mg L(-1)) of the infiltrated effluent causes anoxic conditions and mobilization of dissolved manganese from the soil. An additional emerging problem is the occurrence of persistent trace organic compounds (TrOCs) in reclaimed water that should be removed prior to reuse. An innovative hybrid process based on biofiltration, ozonation and short SAT with ∼22 d HRT is proposed for treatment of the Shafdan secondary effluent to overcome limitations of the existing system and to reduce the SAT's physical footprint. Besides efficient removal of particulate matter to minimize clogging, coagulation/flocculation and filtration (5-6 m h(-1)) operated with the addition of hydrogen peroxide as an oxygen source efficiently removed dissolved organic carbon (DOC, to 17-22%), ammonium and nitrite. This resulted in reduced effluent oxygen demand during infiltration and oxidant (ozone) demand during ozonation by 23 mg L(-1) and 1.5 mg L(-1), respectively. Ozonation (1.0-1.2 mg O3 mg DOC(-1)) efficiently reduced concentrations of persistent TrOCs and supplied sufficient dissolved oxygen (>30 mg L(-1)) for fully oxic operation of the short SAT with negligible Mn(2+) mobilization (<50 μg L(-1)). Overall, the examined hybrid process provided DOC reduction of 88% to a value of 1.2 mg L(-1), similar to conventional SAT, while improving the removal of TrOCs and efficiently preventing manganese dissolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Potential of simple filters to improve microbial quality of irrigation water used in urban vegetable farming in Ghana

DEFF Research Database (Denmark)

Keraita, Bernard; Drechsel, Pay; Konradsen, Flemming

2008-01-01

. As part of a larger study on possible interventions for health risk reduction, the potential of simple interventions was explored. Column slow sand filters with three levels of sand depths (0.5 m, 0.75 m and 1 m) and fabric filters made of nylon, cotton and netting were assessed. More than 600 water...... samples were analyzed for helminth eggs and thermotolerant coliforms. Flow rates were also measured. From slow sand filters, 71-96% of helminths and 2 log units (from 7 to 5 log units) of thermotolerant coliforms were removed. Sand depths had no significant influence in the removal. Lower removal rates...... were achieved by fabric filters, with an average removal of 12-62% for helminth eggs and 1 log unit for thermotolerant coliforms. Nylon filters had higher removal rates especially for helminth eggs (58%). Average flow rates for sand filters were 3 m per day and fabric filters had steady flows of about...

LIQUID EFFLUENT RETENTION FACILITY (LERF) BASIN 42 STUDIES

International Nuclear Information System (INIS)

DUNCAN JB

2004-01-01

This report documents laboratory results obtained under test plan RPP-21533 for samples submitted by the Effluent Treatment Facility (ETF) from the Liquid Effluent Retention Facility (LERF) Basin 42 (Reference 1). The LERF Basin 42 contains process condensate (PC) from the 242-A Evaporator and landfill leachate. The ETF processes one PC campaign approximately every 12 to 18 months. A typical PC campaign volume can range from 1.5 to 2.5 million gallons. During the September 2003 ETF Basin 42 processing campaign, a recurring problem with 'gelatinous buildup' on the outlet filters from 60A-TK-I (surge tank) was observed (Figure 1). This buildup appeared on the filters after the contents of the surge tank were adjusted to a pH of between 5 and 6 using sulfuric acid. Biological activity in the PC feed was suspected to be the cause of the gelatinous material. Due to this buildup, the filters (10 (micro)m CUNO) required daily change out to maintain process throughput

LIQUID EFFLUENT RETENTION FACILITY (LERF) BASIN 42 STUDIES

Energy Technology Data Exchange (ETDEWEB)

DUNCAN JB

2004-10-29

This report documents laboratory results obtained under test plan RPP-21533 for samples submitted by the Effluent Treatment Facility (ETF) from the Liquid Effluent Retention Facility (LERF) Basin 42 (Reference 1). The LERF Basin 42 contains process condensate (PC) from the 242-A Evaporator and landfill leachate. The ETF processes one PC campaign approximately every 12 to 18 months. A typical PC campaign volume can range from 1.5 to 2.5 million gallons. During the September 2003 ETF Basin 42 processing campaign, a recurring problem with 'gelatinous buildup' on the outlet filters from 60A-TK-I (surge tank) was observed (Figure 1). This buildup appeared on the filters after the contents of the surge tank were adjusted to a pH of between 5 and 6 using sulfuric acid. Biological activity in the PC feed was suspected to be the cause of the gelatinous material. Due to this buildup, the filters (10 {micro}m CUNO) required daily change out to maintain process throughput.

Radioactive and electron microscope analysis of effluent monitor sample lines

International Nuclear Information System (INIS)

Kowalski, J.F.

1986-01-01

Effluent air sampling at nuclear power plant often leads to the question ''How representative is the sample of the effluent stream?'' Samples from radiation monitors are typically obtained at great distances from the sample nozzle because of high background concerns under postulated accidents. Sample line plateout during normal effluent sampling becomes the major concern. A US Nuclear Regulatory Commission inspection raised a concern that monitors were not collecting representative samples per ANSI standard N13.1. A comprehensive 2-yr study at Beaver Valley was performed during normal effluent releases in two phases: 1) weekly charcoal and glass fiber filter samples were analyzed for radioactivity for 6 months, and 2) nuclepore membrane filter samples were analyzed by electron microscope for 4- and 6-h periods. A specially designed test nozzle was directly inserted into an effluent stream for comparison with the radiation monitor samples. Particle behavior characteristics can be determined during effluent releases using a simple test probe. While particle plateout was the major purpose of the study, other particle behavior characteristics were evident and equally as important. Particle travel through long sample lines can also lead to (a) agglomeration or the coagulation of smaller particles to form larger ones, (b) particle splitting or fracturing upon impact with the sample line interior walls, and (c) resuspension of large particles in sample lines

200 Area Liquid Effluent Facilities -- Quality assurance program plan

International Nuclear Information System (INIS)

Fernandez, L.

1995-01-01

This Quality Assurance Program Plan (QAPP) describes the quality assurance and management controls used by the 200 Area Liquid Effluent Facilities (LEF) to perform its activities in accordance with DOE Order 5700.6C. The 200 Area LEF consists of the following facilities: Effluent Treatment Facility (ETF); Treated Effluent Disposal Facility (TEDF); Liquid Effluent Retention facility (LERF); and Truck Loading Facility -- (Project W291). The intent is to ensure that all activities such as collection of effluents, treatment, concentration of secondary wastes, verification, sampling and disposal of treated effluents and solids related with the LEF operations, conform to established requirements

Disinfection of secondary effluent by gamma radiation inactivation efficiency and regrowth

International Nuclear Information System (INIS)

Sekiguchi, M.; Sawai, T.; Shimokawa, T.; Sawai, T.

1992-01-01

Inactivation efficiencies of several microorganisms in secondary effluents (SE) from sewage treatment plants by gamma radiation were investigated. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae inoculated in SE were very sensitive but Streptcoccus sp. was resistant to gamma radiation. In addition, no significant difference was found between the combined sewer system and the separate sewer system in regards to the inactivation efficiencies of the bacteria inoculated in the SE. The number of total bacteria in SE was rapidly decreased in the dose range of 0 to 0.2-0.3 kGy but the number gradually fell over the dose range. Moreover, the number of total coliforms almost exponentially decreased with increasing dose, and fell to undetectable levels at about 0.5 kGy. Because of the decrease of the initial bacteria number in SE, adequate filtrating treatments were effective in lowering the irradiation dose for disinfection. Further, the effects of filtrating treatment on bacteria regrowth in SE are discussed. (author)

The impact of recirculation, ventilation and filters on secondary organic aerosols generated by indoor chemistry

DEFF Research Database (Denmark)

Fadeyi, M.O.; Weschler, Charles J.; Tham, K.W.

2009-01-01

This study examined the impact of recirculation rates (7 and 14 h(-1)), ventilation rates (1 and 2 h(-1)), and filtration on secondary organic aerosols (SOAs) generated by ozone of outdoor origin reacting with limonene of indoor origin. Experiments were conducted within a recirculating air handling......, but this was more than offset by the increased dilution of SOA derived from ozone-initiated chemistry. The presence of a particle filter (new or used) strikingly lowered SOA number and mass concentrations compared with conditions when no filter was present. Even though the particle filter in this study had only 35...

Simultaneous C and N removal from saline salmon effluents in filter reactors comprising anoxic-anaerobic-aerobic processes: effect of recycle ratio.

Science.gov (United States)

Giustinianovich, Elisa A; Aspé, Estrella R; Huiliñir, César E; Roeckel, Marlene D

2014-01-01

Salmon processing generates saline effluents with high protein load. To treat these effluents, three compact tubular filter reactors were installed and an integrated anoxic/anaerobic/aerobic process was developed with recycling flow from the reactor's exit to the inlet stream in order to save organic matter (OM) for denitrification. The reactors were aerated in the upper section with recycle ratios (RR) of 0, 2, and 10, respectively, at 30°C. A tubular reactor behave as a plug flow reactor when RR = 0, and as a mixed flow reactor when recycle increases, thus, different RR values were used to evaluate how it affects the product distribution and the global performance. Diluted salmon process effluent was prepared as substrate. Using loads of 1.0 kg COD m(-3)d(-1) and 0.15 kg total Kjeldahl nitrogen (TKN) m(-3)d(-1) at HRT of 2 d, 100% removal efficiencies for nitrite and nitrate were achieved in the anoxic-denitrifying section without effect of the dissolved oxygen in the recycled flow on denitrification. Removals >98% for total organic carbon (TOC) was achieved in the three reactors. The RR had no effect on the TOC removal; nevertheless a higher efficiency in total nitrogen removal in the reactor with the highest recycle ratio was observed: 94.3% for RR = 10 and 46.6% for RR = 2. Results showed that the proposed layout with an alternative distribution in a compact reactor can efficiently treat high organic carbon and nitrogen concentrations from a saline fish effluent with OM savings in denitrification.

Preliminary analysis on the water quality index (WQI) of irradiated basic filter elements

Science.gov (United States)

Arif Abu Bakar, Asyraf; Muhamad Pauzi, Anas; Aziz Mohamed, Abdul; Syima Sharifuddin, Syazrin; Mohamad Idris, Faridah

2018-01-01

Simple water filtration system is needed in times of extreme floods. Clean water for sanitation at evacuation centres is essential and its production is possible by using the famous simple filtration system consisting of empty bottle and filter elements (sands, gravels, cotton/coffee filter). This research intends to study the effects of irradiated filter elements on the filtration effectiveness through experiments. The filter elements will be irradiated with gamma and neutron radiation using the facilities available at Malaysia Nuclear Agency. The filtration effectiveness is measured using the water quality index (WQI) that is developed in this study to reflect the quality of filtered water. The WQI of the filtered water using the system with irradiated filter elements is then compared with that of the system with non-irradiated filter elements. This preliminary analysis only focus on filtration element of silica sand. Results shows very nominal variation in in WQI after filtered by non-irradiated, gamma and neutron filter element (silica sand), where the hypothesis could not be affirmed.

Test of precoat filtration technology for treatment of swimming pool water.

Science.gov (United States)

Christensen, Morten Lykkegaard; Klausen, Morten Møller; Christensen, Peter Vittrup

2018-02-01

The technical performance of a precoat filter was compared with that of a traditional sand filter. Particle concentration and size distribution were measured before and after the filtration of swimming pool water. Both the sand and precoat filters could reduce the particle concentration in the effluent. However, higher particle removal efficiency was generally observed for the precoat filter, especially for particles smaller than 10 μm in diameter. Adding flocculant improved the removal efficiency of the sand filter, resulting in removal efficiencies comparable to those of the precoat filter. Three powders, i.e., two types of perlite (Harbolite ® and Aquatec perlite) and cellulose fibers (Arbocel ® ), were tested for the precoat filter, but no significant difference in particle removal efficiency was observed among them. The maximum efficiency was reached within 30-40 min of filtration. The energy required for the pumps increased by approximately 35% over a period of 14 days. The energy consumption could be reduced by replacing the powder on the filter cloth. The sand filter was backwashed once a week, while the powder on the precoat filter was replaced every two weeks. Under these conditions, it was possible to reduce the water used for cleaning by 88% if the precoat filter was used instead of the sand filter.

Treatment of municipal wastewater in full-scale on-site sand filter reduces BOD efficiently but does not reach requirements for nitrogen and phosphorus removal.

Science.gov (United States)

Laaksonen, Petteri; Sinkkonen, Aki; Zaitsev, Gennadi; Mäkinen, Esa; Grönroos, Timo; Romantschuk, Martin

2017-04-01

A traditional sand filter for treatment of household wastewater was constructed in the fall of 2012 at Biolinja 12, Turku, Finland. Construction work was led and monitored by an authorized wastewater treatment consultant. The filter was placed on a field bordered by open ditches from all sides in order to collect excess rain and snowmelt waters. The filter was constructed and insulated from the environment so that all outflowing water was accounted for. Untreated, mainly municipal, wastewater from Varissuo suburb was pumped from a sewer separately via three septic tanks (volume = 1 m 3 each) into the filters. Normally, wastewater was distributed to ground filters automatically according to pre-programmed schedule. Initially, the daily flow was 1200 L day -1 to reflect the average organic load of a household of five persons (load: ca 237 g day -1 BOD; 73 g day -1 total N; and 10.4 g day -1 total P). Later in the test, the flow rate was decreased first to 900 and then to 600 L day -1 to better reflect the average volume produced by five persons. Volumes of inlet wastewater as well as treated water were monitored by magnetic flow meters. Samples were withdrawn from the inlet water, from the water entering the filters after the third septic tank, and from the outflowing water. After an initial adaption time, the reductions in BOD and chemical oxygen demand were constantly between 92 and 98%, showing that the biological degradation process in the filters functioned optimally and clearly comply with the national and EU standards. The reduction in total nitrogen and total phosphorus, however, reached required levels only during the first months of testing, apparently when buildup of microbial biomass was still ongoing. After this initial period of 3 months showing satisfactory reduction levels, the reduction of total nitrogen varied between 5 and 25% and total phosphorus mostly between 50 and 65%. Nitrification was efficient in the filter, but as indicated

Gravity-driven membrane system for secondary wastewater effluent treatment: Filtration performance and fouling characterization

KAUST Repository

Wang, Yiran; Fortunato, Luca; Jeong, Sanghyun; Leiknes, TorOve

2017-01-01

Gravity-driven membrane (GDM) filtration is one of the promising membrane bioreactor (MBR) configurations. It operates at an ultra-low pressure by gravity, requiring a minimal energy. The objective of this study was to understand the performance of GDM filtration system and characterize the biofouling formation on a flat sheet membrane. This submerged GDM reactor was operated at constant gravitational pressure in treating of two different concentrations of secondary wastewater effluent. Morphology of biofilm layer was acquired by an in-situ and on-line optical coherence tomography (OCT) scanning in a fixed position at regular intervals. The thickness and roughness calculated from OCT images were related to the variation of flux, fouling resistance and permeate quality. At the end of experiment, fouling was quantified by total organic carbon (TOC) and adenosine tri-phosphate (ATP) method. Confocal laser scanning microscopy (CLSM) was also applied for biofouling morphology observation. The biofouling formed on membrane surface was mostly removed by physical cleaning confirmed by contact angle measurement before and after cleaning. This demonstrated that fouling on the membrane under ultra-low pressure operation was highly reversible. The superiority and sustainability of GDM in both flux maintaining and long-term operation with production of high quality effluent was demonstrated.

Gravity-driven membrane system for secondary wastewater effluent treatment: Filtration performance and fouling characterization

KAUST Repository

Wang, Yiran

2017-04-21

Gravity-driven membrane (GDM) filtration is one of the promising membrane bioreactor (MBR) configurations. It operates at an ultra-low pressure by gravity, requiring a minimal energy. The objective of this study was to understand the performance of GDM filtration system and characterize the biofouling formation on a flat sheet membrane. This submerged GDM reactor was operated at constant gravitational pressure in treating of two different concentrations of secondary wastewater effluent. Morphology of biofilm layer was acquired by an in-situ and on-line optical coherence tomography (OCT) scanning in a fixed position at regular intervals. The thickness and roughness calculated from OCT images were related to the variation of flux, fouling resistance and permeate quality. At the end of experiment, fouling was quantified by total organic carbon (TOC) and adenosine tri-phosphate (ATP) method. Confocal laser scanning microscopy (CLSM) was also applied for biofouling morphology observation. The biofouling formed on membrane surface was mostly removed by physical cleaning confirmed by contact angle measurement before and after cleaning. This demonstrated that fouling on the membrane under ultra-low pressure operation was highly reversible. The superiority and sustainability of GDM in both flux maintaining and long-term operation with production of high quality effluent was demonstrated.

Performance comparison of sand and fine sawdust vermifilters in treating concentrated grey water for urban poor.

Science.gov (United States)

Adugna, Amare T; Andrianisa, Harinaivo A; Konate, Yacouba; Ndiaye, Awa; Maiga, Amadou H

2015-01-01

A comparative investigation was conducted for 10 months with sand and fine sawdust vermifilters and a control unit to treat concentrated grey water generated from a poor urban household in Ouagadougou, Burkina Faso. Each of the filters was made up of cylindrical DN200-PVC pipes and filled with 10 cm of gravel at the bottom. On top of the gravel layer, filter 1 (fully sand, F1) was completed with 40 cm of sand and 10 cm of fine sawdust, filter 2 (partially sand, F2) with 20 cm of sand and 30 cm of fine sawdust, respectively, and filter 3 (fully sawdust, F3) and 4 (control, F4) with 50 cm of fine sawdust only. Two hundred Eudrilus eugeniae earthworms were inoculated in each of the vermifilters. The vermifiltration system was supplied with grey water four times per day at a hydraulic loading rate of 64 L/m(2)/day on a batch basis. The removal efficiencies of biological oxygen demand, total chemical oxygen demand, and dissolved chemical oxygen demand (dCOD) by the vermifilters were 25-30% higher than the control, but little differences were observed in terms of total suspended solids and coliform removal efficiencies. Though there was no significant difference in the performance of the three vermifilters (p > 0.05), except for dCOD removal efficiency, the lifespan of F2 and F3 was longer than that of F1. Therefore, fine sawdust can substitute sand as a filter medium in vermifilters.

Legal provisions governing gaseous effluents radiological monitoring

International Nuclear Information System (INIS)

Winkelmann, I.

1985-01-01

This contribution explains the main provisions governing radiological monitoring of gaseous effluents from LWR type nuclear power plants. KTA rule 1503.1 defines the measuring methods and tasks to be fulfilled by reactor operators in order to safeguard due monitoring and accounting of radioactive substances in the plants' gaseous effluents. The routine measurements are checked by a supervisory programme by an independent expert. The routine controls include analysis of filter samples, comparative measurement of radioactive noble gases, interlaboratory comparisons, and comparative evaluation of measured values. (DG) [de

Aerosol generation and filter behaviour in sodium fires. [LMFBR

Energy Technology Data Exchange (ETDEWEB)

Boehm, L; Jordan, S

1975-11-01

In the scope of a long-term program (a) aerosol-formation rates during Na fires, (b) the behavior of Na aerosols in a closed system, and (c) the filtration of Na aerosols were investigated. These experiments in the ABRAUS facility should simulate the behaviour of Na aerosols after an accident in the inner and outer containment of the sodium-cooled fast Reactor SNR 300. At the conditions of the inner-containment (0.7% oxygen content in the atmosphere) aerosol-concentrations by Na - 0/sub 2/ reactions of 1 - 10 g/m/sup 3/ are possible. At the conditions of the outer-containment (21% 0/sub 2/-content) aerosol-concentrations at Na fires of 10 - 50 g/m/sup 3/ have been measured. The aerosol-formation rates are proportional to the 0/sub 2/-concentration: the rate at 21% 0/sub 2/-concentration is about 10-times higher than the rate at 0.7% 0/sub 2/. The aerosol formation rate was determined to 20 kgNa/m/sup 2/h at 21% 0/sub 2/. The behaviour of sand-bed-filters was investigated. A sand-bed-filter arrangement was developed which is better than HEPA-standard of fiberglas-filters concerning efficiency (better than 99.99) and load capacity (about 500 g Na/sub 2/0/sub 2//m/sup 2/). Beyond that sand-bed-filters resist high pressure- and temperature-peaks. Liquid Na aerosols are filtered with an efficiency better than 99.9%. A physical model was evaluated to explain pressure increase at the sand-bed-filter during load and penetration of the filter. The calculated values were in good agreement with experimental results.

The uranium recovery from UO{sub 2} kernel production effluent

Energy Technology Data Exchange (ETDEWEB)

Chen, Xiaotong, E-mail: chenxiaotong@tsinghua.edu.cn; He, Linfeng; Liu, Bing; Tang, Yaping; Tang, Chunhe

2016-12-15

Graphical abstract: In this study, a flow sheet including evaporation, flocculation, filtration, adsorption, and reverse osmosis was established for the UO{sub 2} kernel production effluent of HTR spherical fuel elements. The uranium recovery could reach 99.9% after the treatment, with almost no secondary pollution produced. Based on the above experimental results, the treating flow process in this study would be feasible for laboratory- and engineering-scale treatment of UO{sub 2} kernel production effluent of HTR spherical fuel elements. - Highlights: • A flow sheet including evaporation, flocculation, filtration, adsorption, and reverse osmosis was established for the UO{sub 2} kernel production effluent. • The uranium recovery could reach 99.9% after the treatment, with almost no secondary pollution produced. • The treating flow process would be feasible for laboratory- and engineering-scale treatment of UO{sub 2} kernel production effluent. - Abstract: For the fabrication of coated particle fuel elements of high temperature gas cooled reactors, the ceramic UO{sub 2} kernels are prepared through chemical gelation of uranyl nitrate solution droplets, which produces radioactive effluent with components of ammonia, uranium, organic compounds and ammonium nitrate. In this study, a flow sheet including evaporation, flocculation, filtration, adsorption, and reverse osmosis was established for the effluent treating. The uranium recovery could reach 99.9% after the treatment, with almost no secondary pollution produced.

Removal of organic contaminants from secondary effluent by anodic oxidation with a boron-doped diamond anode as tertiary treatment

Energy Technology Data Exchange (ETDEWEB)

Garcia-Segura, Sergi, E-mail: sergigarcia@ub.edu [Advanced Water Management Centre, The University of Queensland, Level 4, Gehrmann Bld. (60), St Lucia, QLD 072 (Australia); Laboratori d’Electroquímica dels Materials i del Medi Ambient, Departament de Química Física, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona (Spain); Keller, Jürg [Advanced Water Management Centre, The University of Queensland, Level 4, Gehrmann Bld. (60), St Lucia, QLD 072 (Australia); Brillas, Enric [Laboratori d’Electroquímica dels Materials i del Medi Ambient, Departament de Química Física, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona (Spain); Radjenovic, Jelena, E-mail: j.radjenovic@awmc.uq.edu.au [Advanced Water Management Centre, The University of Queensland, Level 4, Gehrmann Bld. (60), St Lucia, QLD 072 (Australia)

2015-02-11

Graphical abstract: - Highlights: • Mineralization of secondary effluent by anodic oxidation with BDD anode. • Complete removal of 29 pharmaceuticals and pesticides at trace level concentrations. • Organochlorine and organobromine byproducts were formed at low μM concentrations. • Chlorine species evolution assessed to evaluate the anodic oxidation applicability. - Abstract: Electrochemical advanced oxidation processes (EAOPs) have been widely investigated as promising technologies to remove trace organic contaminants from water, but have rarely been used for the treatment of real waste streams. Anodic oxidation with a boron-doped diamond (BDD) anode was applied for the treatment of secondary effluent from a municipal sewage treatment plant containing 29 target pharmaceuticals and pesticides. The effectiveness of the treatment was assessed from the contaminants decay, dissolved organic carbon and chemical oxygen demand removal. The effect of applied current and pH was evaluated. Almost complete mineralization of effluent organic matter and trace contaminants can be obtained by this EAOP primarily due to the action of hydroxyl radicals formed at the BDD surface. The oxidation of Cl{sup −} ions present in the wastewater at the BDD anode gave rise to active chlorine species (Cl{sub 2}/HClO/ClO{sup −}), which are competitive oxidizing agents yielding chloramines and organohalogen byproducts, quantified as adsorbable organic halogen. However, further anodic oxidation of HClO/ClO{sup −} species led to the production of ClO{sub 3}{sup −} and ClO{sub 4}{sup −} ions. The formation of these species hampers the application as a single-stage tertiary treatment, but posterior cathodic reduction of chlorate and perchlorate species may reduce the risks associated to their presence in the environment.

The effect of anaerobic baffled reactor effluent on nitrogen and ...

African Journals Online (AJOL)

Leaching of nitrogen and phosphorus from soil columns during application of anaerobic baffled reactor effluent was evaluated. The soils used were from Inanda (Ia), Cartref (Cf), and Sepane (Se) forms, and a silica sand (SS). Each was packed into duplicate columns (103 mm internal diameter; 200 mm length), four each for ...

The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska

Energy Technology Data Exchange (ETDEWEB)

Bartelt-Hunt, Shannon L. [Department of Civil Engineering, University of Nebraska-Lincoln, 203B Peter Kiewit Institute, Omaha, NE 68182-0178 (United States)], E-mail: sbartelt2@unl.edu; Snow, Daniel D.; Damon, Teyona [Water Sciences Laboratory, University of Nebraska-Lincoln, Lincoln, NE 68583-0844 (United States); Shockley, Johnette [Department of Civil Engineering, University of Nebraska-Lincoln, 203B Peter Kiewit Institute, Omaha, NE 68182-0178 (United States); Hoagland, Kyle [UNL Water Center, University of Nebraska-Lincoln, Lincoln, NE 68583-0995 (United States)

2009-03-15

The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at four sites and in a discharge canal at a fifth location. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant source of pharmaceutical loading to the receiving waters. Effluents from WWTPs with trickling filters or trickling filters in parallel with activated sludge resulted in the highest observed in-stream pharmaceutical concentrations. Azithromycin, caffeine, 1,7-dimethylzanthine, carbamazepine, cotinine, DEET, diphenhydramine, and sulfamethazine were detected at all locations. Methamphetamine, an illicit pharmaceutical, was detected at all but one of the sampling locations, representing only the second report of methamphetamine detected in WWTP effluent and in streams impacted by WWTP effluent. - Passive samplers were used to develop semi-quantitative estimates of pharmaceutical concentrations in receiving waters influenced by wastewater effluent.

The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska

International Nuclear Information System (INIS)

Bartelt-Hunt, Shannon L.; Snow, Daniel D.; Damon, Teyona; Shockley, Johnette; Hoagland, Kyle

2009-01-01

The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at four sites and in a discharge canal at a fifth location. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant source of pharmaceutical loading to the receiving waters. Effluents from WWTPs with trickling filters or trickling filters in parallel with activated sludge resulted in the highest observed in-stream pharmaceutical concentrations. Azithromycin, caffeine, 1,7-dimethylzanthine, carbamazepine, cotinine, DEET, diphenhydramine, and sulfamethazine were detected at all locations. Methamphetamine, an illicit pharmaceutical, was detected at all but one of the sampling locations, representing only the second report of methamphetamine detected in WWTP effluent and in streams impacted by WWTP effluent. - Passive samplers were used to develop semi-quantitative estimates of pharmaceutical concentrations in receiving waters influenced by wastewater effluent

Evaluation of an Intergrated / Biocoagulant-sand filter Drum for ...

African Journals Online (AJOL)

User

2015-03-18

Mar 18, 2015 ... to adopt simple sand filtration for water treatment is exigent. ... Moringa oleifera, a vegetable plant found across Africa have been noted ... leachate samples from waste dumps within the city of Bamenda .... Total solids mg/dm3.

Filter case for separating out radioactive effluents from gas flows

International Nuclear Information System (INIS)

Jannakos, K.; Zabel, G.

1982-01-01

A remotely operated change of filter in a filter case can be done with an annular or cylindrical filter insert, where the contaminated air side remains separate from the clean air side. A lid is provided which can be divided into two parts, and by which the openings of the filter insert and also in the intermediate floor can be opened or closed using the double lid technique. When closing the filter case lid, the double lid closure is always opened. (DG) [de

Can those organic micro-pollutants that are recalcitrant in activated sludge treatment be removed from wastewater by biofilm reactors (slow sand filters)?

International Nuclear Information System (INIS)

Escolà Casas, Mònica; Bester, Kai

2015-01-01

The degradation of seven compounds which are usually recalcitrant in classical activated sludge treatment (e.g., diclofenac, propranolol, iopromide, iohexol, iomeprol tebuconazole and propiconazole) was studied in a biofilm reactor (slow sand filtration). This reactor was used to treat real effluent-wastewater at different flow rates (hydraulic loadings) under aerobic conditions so removal and degradation kinetics of these recalcitrant compounds were calculated. With the hydraulic loading rate of 0.012 m 3 m 2 h −1 the reactor removed 41, 94, 58, 57 and 85% of diclofenac, propranolol, iopromide, iohexol and iomeprol respectively. For these compounds the removal efficiency was dependent on hydraulic residence-times. Only 59 and 21% of the incoming tebuconazole and propiconazole respectively were removed but their removal did not depend on hydraulic residence time. Biofilm reactors are thus efficient in removing micro-pollutants and could be considered as an option for advanced treatment in small wastewater treatment plants. - Highlights: • A biofilm reactor (biofilter) can remove micro-pollutants from WWTP effluent. • Sorption could be excluded as the dominant removal mechanism. • Biodegradation was responsible for removing seven compounds. • The removal efficiency was usually proportional to the hydraulic residence-time. • Single first-order removal rates apply for most compounds

Can those organic micro-pollutants that are recalcitrant in activated sludge treatment be removed from wastewater by biofilm reactors (slow sand filters)?

Energy Technology Data Exchange (ETDEWEB)

Escolà Casas, Mònica; Bester, Kai, E-mail: kb@dmu.dk

2015-02-15

The degradation of seven compounds which are usually recalcitrant in classical activated sludge treatment (e.g., diclofenac, propranolol, iopromide, iohexol, iomeprol tebuconazole and propiconazole) was studied in a biofilm reactor (slow sand filtration). This reactor was used to treat real effluent-wastewater at different flow rates (hydraulic loadings) under aerobic conditions so removal and degradation kinetics of these recalcitrant compounds were calculated. With the hydraulic loading rate of 0.012 m{sup 3} m{sup 2} h{sup −1} the reactor removed 41, 94, 58, 57 and 85% of diclofenac, propranolol, iopromide, iohexol and iomeprol respectively. For these compounds the removal efficiency was dependent on hydraulic residence-times. Only 59 and 21% of the incoming tebuconazole and propiconazole respectively were removed but their removal did not depend on hydraulic residence time. Biofilm reactors are thus efficient in removing micro-pollutants and could be considered as an option for advanced treatment in small wastewater treatment plants. - Highlights: • A biofilm reactor (biofilter) can remove micro-pollutants from WWTP effluent. • Sorption could be excluded as the dominant removal mechanism. • Biodegradation was responsible for removing seven compounds. • The removal efficiency was usually proportional to the hydraulic residence-time. • Single first-order removal rates apply for most compounds.

Full-scale operating experience of deep bed denitrification filter achieving phosphorus.

Science.gov (United States)

Husband, Joseph A; Slattery, Larry; Garrett, John; Corsoro, Frank; Smithers, Carol; Phipps, Scott

2012-01-01

The Arlington County Wastewater Pollution Control Plant (ACWPCP) is located in the southern part of Arlington County, Virginia, USA and discharges to the Potomac River via the Four Mile Run. The ACWPCP was originally constructed in 1937. In 2001, Arlington County, Virginia (USA) committed to expanding their 113,500 m³/d, (300,000 pe) secondary treatment plant to a 151,400 m³/d (400,000 pe) to achieve effluent total nitrogen (TN) to phosphorus (TP) phosphorus, to very low concentrations. This paper will review the steps from concept to the first year of operation, including pilot and full-scale operating data and the capital cost for the denitrification filters.

Utilization of artificial recharged effluent for irrigation: pollutants' removal and risk assessment

Directory of Open Access Journals (Sweden)

Liangliang Wei

2017-03-01

Full Text Available The reclaimed water from soil aquifer treatment (SAT column was reused for irrigation as the source water, pollutants' removal and health risk assessment was analyzed via the comparison with secondary and tertiary effluents. The effect of the SAT pre-treatment on the qualities and growth of different crops (Lachca sativa – lettuce, Brasica rapa var chinensis – pak choi, Cucumis sativus – cucumber, Brassica oleracea – cabbage, and Zea mays – maize were evaluated. Experimental results demonstrated that the tertiary and SAT treatments had no significant effect on the crop qualities, and could efficiently decrease the accumulation of heavy metals (especially for SAT pre-treatment. Moreover, the carcinogenic risk of the chemical carcinogens for the 1.5 m SAT effluent irrigation declined roughly an order of magnitude as compared with the secondary effluent, and three to four orders of magnitude decreasing of the virus risk. These findings are significant for the safe and cheap reuse of secondary effluent for irrigation purposes.

Analysis of substrate degradation, metabolite formation and microbial community responses in sand bioreactors treating winery wastewater: a comparative study.

Science.gov (United States)

Welz, P J; Palmer, Z; Isaacs, S; Kirby, B; le Roes-Hill, M

2014-12-01

There is a global need for the implementation of more cost-effective green technologies for the treatment of effluent from wineries. However, systems reliant on microbial biodegradation may be adversely affected by the highly seasonal character of cellar waste. In this study, the biodegradation of two different formulations of winery effluent in sand bioreactors was compared. The degradation of organic substrates and formation of metabolites was monitored by physicochemical analyses of pore water and final effluent samples. Changes in the bacterial community structures were detected using molecular fingerprinting. In wastewater with an overall COD of 2027 mg/L, a formulation with a high concentration of acetate (800 mg COD/L) was more recalcitrant to degradation than a formulation with a high concentration of glucose (800 mg COD/L). Ethanol, glucose and phenolics were degraded preferentially in the deeper layers of the sand bioreactors (average Eh 25 mV) than in the superficial layers (average Eh 102 mV). The redox status also played a pivotal role on the bacterial community composition. The study yielded valuable insight that can be utilized in the design (configuration and operation) of full scale sand bioreactors. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ozonation performance of WWTP secondary effluent of antibiotic manufacturing wastewater.

Science.gov (United States)

Zheng, Shaokui; Cui, Cancan; Liang, Qianjin; Xia, Xinghui; Yang, Fan

2010-11-01

The ozonation performance of wastewater treatment plant secondary effluent of oxytetracycline (OTC) manufacturing wastewater was investigated in terms of ozone dosage and initial pH levels when OTC contributed to a negligible fraction in the chemical oxygen demand (COD) ingredients of the medium-organic-strength wastewater with low biodegradability. A particular emphasis was placed on ammonia, OTC, and residual antibacterial activity (RAA) (evaluated using the objective pathogenic bacterium Staphylococcus aureus). It appears that an ozone dosage of 657 mg L⁻¹ (120 min of reaction) was enough to achieve an OTC abatement of 96%, and COD and biochemical oxygen demand removals of 29% and 33%, respectively, at initial levels of 10.4, 1360, and 300 mg L⁻¹ , respectively. There is a clear correlation between complete OTC depletion and complete RAA disappearance with an increase of ozone dosage. The presence of plentiful non-antibiotic refractory substances influenced the determination of the optimum ozone dosage for biodegradability enhancement and OTC/RAA reduction as well as the ozonation transformation of NH(3). The initial pH adjustment from the original level (pH 9) to pH 11 significantly reduced COD removal while RAA and NH(3) levels were not significantly influenced. Copyright © 2010 Elsevier Ltd. All rights reserved.

Utilization of vinasse effluents from an anaerobic reactor

Energy Technology Data Exchange (ETDEWEB)

Costa, F J.C.B.; Rocha, B B.M.; Viana, C E; Toledo, A C

1986-01-01

An anaerobic reactor was developed to biodigest alcohol distillery wastes. A further post-treatment of the effluent reduced the level of pollution to the point of eventually discharging into streams and rivers. The present work also analyses the use of biodigested vinasse as a source of food for fish. Very high efficiencies were obtained during primary and secondary treatment of vinasse effluent, as demonstrated by the greatly reduced organic load. The utilization of the treated effluent as a source of fish food presents an excellent alternative for the Brazilian alcohol industry. (Refs. 6).

Comparison of six sewage effluents treated with different treatment technologies-Population level responses in the harpacticoid copepod Nitocra spinipes

International Nuclear Information System (INIS)

Lundstroem, Elin; Bjoerlenius, Berndt; Brinkmann, Markus; Hollert, Henner; Persson, Jan-Olov; Breitholtz, Magnus

2010-01-01

Since conventional treatment technologies may fail in removing many micro-pollutants, there is currently a focus on the potential of additional treatment technologies for improved sewage treatment. The aim of the present study was to evaluate six different effluents from Henriksdal Sewage Treatment Plant in Stockholm, Sweden. The effluents were; conventionally treated effluent (chemical phosphorous removal in combination with an activated sludge process, including biological nitrogen removal and a sand filter), with additional treatments individually added to the conventional treatment; active carbon filtration, ozonation at 5 mg l -1 , ozonation at 15 mg l -1 , ozonation at 5 mg l -1 + moving bed biofilm reactor and irradiation with ultraviolet radiation + hydrogen peroxide. The evaluation was done by characterizing and comparing the effluents using a Lefkovitch matrix model based on a life cycle test with the harpacticoid copepod Nitocra spinipes, combined with analysis of juvenile development and survival over time. The conventionally treated effluent resulted in the most negative effects, leading to the conclusion that all additional treatments in the present study created effluents with less negative impacts on the copepod populations. The ozone treatments with the low dose treatment in particular, resulted in the overall least negative effects. Moving bed biofilm reactor combined with ozone did not improve the quality of the effluent in the sense that slightly more negative effects on the population abundance were seen for this treatment technology compared to ozonation alone. The active carbon treatment had more negative effects than the ozone treatments, most of which could possibly be explained by removal of essential metal ions. The effluent which was treated with ultraviolet radiation + hydrogen peroxide resulted in few developmental and survival effects over time, but still showed negative effects on the population level. Matrix population modeling

Phosphorus retention in a 20-year-old septic system filter bed.

Science.gov (United States)

Robertson, W D

2012-01-01

Septic systems in lakeshore environments often occur where thin soils overlie bedrock and, consequently, filter beds may be constructed of imported filter sand. The objective of this study was to assess the mobility of wastewater phosphorus (P) in such a potentially vulnerable setting by examining a 20-yr-old domestic septic system located near Parry Sound, ON, Canada, where the filter bed is constructed of imported noncalcareous sand. The groundwater plume is acidic (pH 6.0) and has a zone of elevated PO-P (up to 3.1 ± 1.7 mg L) below the tile lines but no elevated PO-P is present beyond 5 m from the tile lines. Elevated concentrations of desorbable P (up to 137 mg kg) and acid-extractable P (up to 3210 mg kg) occur in the filter sand within 1 m below four of seven tile lines present and the total mass of excess acid-extractable P (39 kg) is similar to the estimated total lifetime P loading to the system (33 kg). Microprobe images reveal abundant Fe and Al-rich authigenic mineral coatings on the sand grains that are increasingly P rich (up to 10% w/w P) near the tile lines. Additionally, 6 yr of monitoring data show that groundwater PO concentrations are not increasing. This indicates that mineral precipitation, not adsorption, dominates P immobilization at this site. This example of robust long-term P retention opens up the possibility of improving P removal in on-site treatment systems by prescribing specific sand types for filter bed construction. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Utilization of artificial recharged effluent as makeup water for industrial cooling system: corrosion and scaling.

Science.gov (United States)

Wei, Liangliang; Qin, Kena; Zhao, Qingliang; Noguera, Daniel R; Xin, Ming; Liu, Chengcai; Keene, Natalie; Wang, Kun; Cui, Fuyi

2016-01-01

The secondary effluent from wastewater treatment plants was reused for industrial cooling water after pre-treatment with a laboratory-scale soil aquifer treatment (SAT) system. Up to a 95.3% removal efficiency for suspended solids (SS), 51.4% for chemical oxygen demand (COD), 32.1% for Cl(-) and 30.0% SO4(2-) were observed for the recharged secondary effluent after the SAT operation, which is essential for controlling scaling and corrosion during the cooling process. As compared to the secondary effluent, the reuse of the 1.5 m depth SAT effluent decreased the corrosion by 75.0%, in addition to a 55.1% decline of the scales/biofouling formation (with a compacted structure). The experimental results can satisfy the Chinese criterion of Design Criterion of the Industrial Circulating Cooling Water Treatment (GB 50050-95), and was more efficient than tertiary effluent which coagulated with ferric chloride. In addition, chemical structure of the scales/biofouling obtained from the cooling system was analyzed.

Selection of Clostridium spp. in biological sand filters neutralizing synthetic acid mine drainage.

Science.gov (United States)

Ramond, Jean-Baptiste; Welz, Pamela J; Le Roes-Hill, Marilize; Tuffin, Marla I; Burton, Stephanie G; Cowan, Don A

2014-03-01

In this study, three biological sand filter (BSF) were contaminated with a synthetic iron- [1500 mg L⁻¹ Fe(II), 500 mg L⁻¹ Fe(III)] and sulphate-rich (6000 mg L⁻¹ SO₄²⁻) acid mine drainage (AMD) (pH = 2), for 24 days, to assess the remediation capacity and the evolution of autochthonous bacterial communities (monitored by T-RFLP and 16S rRNA gene clone libraries). To stimulate BSF bioremediation involving sulphate-reducing bacteria, a readily degradable carbon source (glucose, 8000 mg L⁻¹) was incorporated into the influent AMD. Complete neutralization and average removal efficiencies of 81.5 (±5.6)%, 95.8 (±1.2)% and 32.8 (±14.0)% for Fe(II), Fe(III) and sulphate were observed, respectively. Our results suggest that microbial iron reduction and sulphate reduction associated with iron precipitation were the main processes contributing to AMD neutralization. The effect of AMD on BSF sediment bacterial communities was highly reproducible. There was a decrease in diversity, and notably a single dominant operational taxonomic unit (OTU), closely related to Clostridium beijerinckii, which represented up to 65% of the total community at the end of the study period. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Application of novel Modified Biological Aerated Filter (MBAF) as a promising post-treatment for water reuse: Modification in configuration and backwashing process.

Science.gov (United States)

Nikoonahad, Ali; Ghaneian, Mohammad Taghi; Mahvi, Amir Hossein; Ehrampoush, Mohammad Hassan; Ebrahimi, Ali Asghar; Lotfi, Mohammad Hassan; Salamehnejad, Sima

2017-12-01

Biological Aerated Filter (BAF) reactors due to their plentiful biomass, high shockability, high efficiency, good filtration, availability and lack of need for large land areas, are enjoying from great importance in advanced wastewater treatment. Therefore, in this study, Polystyrene Coated by Sand (PCS) was produced as a novel media and its application in a modified down-flow BAF structure for advanced wastewater treatment was assessed in two steps. In step one, the backwash effluent did not return to the system, while in step two backwash effluent returned to increase the water reuse efficiency. The backwash process was also studied through three methods of Top Backwashing (TB), Bottom Backwashing (BB), as well as Top and Bottom Backwashing Simultaneously (TBBS). The results showed that return of backwash effluent had no significant effect on the BAF effluent quality. In the second step similar to the first one with slight differences, the residual average concentrations of TSS, BOD 5 , and COD at the effluent were about 2.5, 8.2, and 25.5 mg/L, respectively. Additionally, in step two, the mean volume of disposal sludge/volume of treated water (v ds /v tw ) decreased a large extent to about 0.088%. In other words, the water reuse has increased to more than 99.91%. The backwash time in methods of TB and BB were 65 and 35 min, respectively; however, it decreased in TBBS methods to 25 min. The concentrations of most effluent parameters in this system are in concordance with the 2012 EPA Agriculture Standards, even for irrigation of Non-processed agricultural crops and livestock water consumption. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 141.553 - My system practices lime softening-is there any special provision regarding my combined filter...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false My system practices lime softening-is... Filter Effluent Requirements § 141.553 My system practices lime softening—is there any special provision regarding my combined filter effluent? If your system practices lime softening, you may acidify...

ENGINEERING STUDY FOR THE 200 AREA EFFLUENT TREATMENT FACILITY (ETF) SECONDARY WASTE TREATMENT OF PROJECTED FUTURE WASTE FEEDS

International Nuclear Information System (INIS)

LUECK, K.J.

2004-01-01

This report documents an engineering study conducted to evaluate alternatives for treating secondary waste in the secondary treatment train (STT) of the Hanford Site 200 Area Effluent Treatment Facility (ETF). The study evaluates ETF STT treatment alternatives and recommends preferred alternatives for meeting the projected future missions of the ETF. The preferred alternative(s) will process projected future ETF influents to produce a solid waste acceptable for final disposal on the Hanford Site. The main text of this report summarizes the ETF past and projected operations, lists the assumptions about projected operations that provide the basis for the engineering evaluation, and summarizes the evaluation process. The evaluation process includes identification of available modifications to the current ETF process, screens those modifications for technical viability, evaluates the technically viable alternatives, and provides conclusions and recommendations based on that evaluation

In-Plant Corrosion Study of Steels in Distillery Effluent Treatment Plant

Science.gov (United States)

Ram, Chhotu; Sharma, Chhaya; Singh, A. K.

2015-05-01

The present study deals with corrosion and performance of steels observed in an effluent treatment plant (ETP) of a distillery. For this purpose, the metal coupons were exposed in primary (untreated effluent) and secondary tank (anaerobic treatment effluent) of the ETP. The extent of attack has been correlated with the composition of the effluent with the help of laboratory immersion and electrochemical tests. Untreated distillery effluent found to be more corrosive than the anaerobic-treated effluents and is assigned due to chloride, phosphate, calcium, nitrate, and nitrite ions, which enhances corrosivity at acidic pH. Mild steel showed highest uniform and localized corrosion followed by stainless steels 304L and 316L and lowest in case of duplex 2205.

Automation of the electromagnetic filter applied for condensation water treatment in the secondary cooling system of the Paks Nuclear Power Plant

International Nuclear Information System (INIS)

Szilagyi, Gyoergy

1989-01-01

A full-flow condensation water purification system is applied in the secondary cooling circuit of the Paks NPP. The electromagnetic filter of the filtering system eliminates ferromagnetic impurities. The filter consists of a high current coil and an automatic control unit. During the improvement of this unit, a FESTO FPC-404 type controller based on an extended capability PLC was installed. (R.P.) 5 figs

Development of a liquid filter testing technique using radioisotope

International Nuclear Information System (INIS)

Kumar, Surender; Ramarathinam, K.; Khan, A.A.

1979-01-01

Efficient removal of suspended matter from liquids was always in demand in industries as a process requirement for the recovery of suspended materials. In nuclear industry the filters are required to remove fine suspended matter from water in reactors, effluent treatment plants, fuel reprocessing plants etc. The filters are used to maintain clarity and to limit the activity level to a minimum. In effluent treatment plants low level liquid waste is discharged to the environment after removing active suspended matter by filters. Various type of liquid filters are available in the market to meet the demands of different industries. These filters must be evaluated for their removal effectiveness for particulate matter from liquids. The filters are evaluated using several techniques like gravimetric analysis, turbidity measurement, direct counting of particles using optical and electronic instruments etc. All the techniques have their own advantages and disadvantages. Counting of radioactive particles using radiation counters is a simple and sensitive technique. It involves the neutron activation of selected test powders which are dispersed in the liquid and led through the test filter; the up-stream and down-stream concentrations are measured using GM counter. This technique was found to be consistent and reproducible in the low, middle and high ranges of efficiency. Selection of a test powder, its activation and use for evaluating liquid filters are dealt with. (auth.)

Granular filters for water treatment: heterogeneity and diagnostic tools

DEFF Research Database (Denmark)

Lopato, Laure Rose

the last barrier against disinfection resistant protozoan pathogens and this has led to increased regulation of the filtration process. To be able to produce high-quality filtrate in a constant and reliable manner while meeting stricter drinking water guideline values, it is important to be able......Rapid granular filters are the most commonly used filters in drinking water treatment plants and are the focus of this PhD study. They are usually constructed with sand, anthracite, activated carbon, garnet sand, and ilmenite and have filtration rates ranging from 3 to 15 m/h. Filters are often...... options prescribed. The diagnostic tools are then used again to verify the efficiency of the solution applied. If the problem is not solved the whole process starts again. These tools are of significant interest for the development of the Water Safety Plans recommended by WHO to monitor filters...

Feasibility for the medium efficiency filter as a postfilter in the air cleaning unit

International Nuclear Information System (INIS)

Lim, H. S.; Jung, D. Y.; Byun, S. C.; Kim, S. H.

2002-01-01

The Air Cleaning Unit (ACU) is provided in a nuclear facility to filter the radioactive materials in gaseous effluents released from the facility during normal operation and during a postulated accident. The Air Cleaning Unit (ACU) consists of pre-HEPA filters, charcoal adsorber, post HEPA filters, fans, etc. The charcoal filters keep on-site dose and off-site effluents ALARA, consistent with regulatory requirements. The function of HEPA filter downstream of charcoal(carbon) adsorber in ACU is to catch potential radioactive carbon dust and to be a backup in the event of failure of upstream HEPA. Previous Regulatory Guide use only post HEPA filter of charcoal adsorber downstream but the Regulatory Guide of current revisions allows use of 95% dust spot efficiency filters in lieu of HEPA at the downstream of the carbon adsorber. In this paper is described that the background information of filters, Current Regulatory Guide of revised by the United States Nuclear Regulatory Commission and the feasibility for the medium efficiency filter as a carbon adsorber post filter in the Air Cleaning Unit

Study of new materials for use as flooded filter media in waste water treatment; Estudio de nuevos materiales como soporte en filtros inundados en la depuracion de aguas residuales

Energy Technology Data Exchange (ETDEWEB)

Zamorano, M.; Hontoria, E. [Universidad de Granada, (Spain)

1998-06-01

The purpose of this study was to investigate pulverized brick taken from brick factories and recycled plastic used to cover crops as supported beds in submerged bi filters for the purification of residual water, which also permit the re-used of recycled or waste products and the clarification and improvement of the effluent flow from the filter. The study of this landfills shows that the ceramic efficiency was 92% COD-removal and 91% SS-removal, with secondary clarification. The study of recycled plastic shows that the efficiency was 88% COD-removal and 84% SS-removal, without secondary clarification. Although the functioning of the system with these materials have not improved 100%, this study has opened up a new field of investigation that will perfect the system and materials. (Author) 10 refs.

Effluents and releases of tritium from Novo-Voronezh-5 reactor

International Nuclear Information System (INIS)

Babenko, A.G.; Mekhedov, B.N.; Podporinova, L.E.; Popov, S.V.; Shalin, A.N.

1990-01-01

Results of systematic measurements of tritium concentration within technological systems of reactor of Novo-Voronezh NPP conducted to evaluate tritium effluents and releases and radiation doses to population from these effluents and releases are given. It is shown that 68% concerning tritium total amount were disposed into sewerage while 17% - through vent tube and 15% - with water and steam from secondary circuit systems. Standartized tritium effluents from WWER-1000 reactor for 5 year run constitute 15±1.9 GBq/MWxyear and it corresponds to mean value of effluents for foreign NPPs. Tritium concentration in the atmosphere constituted according to calculations (4.1-20)x10 -5 Bq/l. Conclusion is made about insignificant dose to population from tritium gaseous effluents. Detail study is necessary for dose connected with tritium contained in water effluents

Suitability of adsorption isotherms for predicting the retention capacity of active slag filters removing phosphorus from wastewater.

Science.gov (United States)

Pratt, C; Shilton, A

2009-01-01

Active slag filters are an emerging technology for removing phosphorus (P) from wastewater. A number of researchers have suggested that adsorption isotherms are a useful tool for predicting P retention capacity. However, to date the appropriateness of using isotherms for slag filter design remains unverified due to the absence of benchmark data from a full-scale, field filter operated to exhaustion. This investigation compared the isotherm-predicted P retention capacity of a melter slag with the P adsorption capacity determined from a full-scale, melter slag filter which had reached exhaustion after five years of successfully removing P from waste stabilization pond effluent. Results from the standard laboratory batch test showed that P adsorption correlated more strongly with the Freundlich Isotherm (R(2)=0.97, Pretention capacity of 0.014 gP/kg slag; markedly lower than the 1.23 gP/kg slag adsorbed by the field filter. Clearly, the result generated by the isotherm bears no resemblance to actual field capacity. Scanning electron microscopy analysis revealed porous, reactive secondary minerals on the slag granule surfaces from the field filter which were likely created by weathering. This slow weathering effect, which generates substantial new adsorption sites, is not accounted for by adsorption isotherms rendering them ineffective in slag filter design.

Design and full scale test of a sand bed filter

International Nuclear Information System (INIS)

Kaercher, M.

1991-01-01

All French pressurized water reactor plants are equipped with a containment venting system. this system is designed and implemented by Electricite de France with the technical support of safety authorities (Institute of Protection and Nuclear Safety of Atomic Energy Commission). This paper covers the following items: main assumptions, sizing and design requirements; basic design of the filter resulting from PITEAS R and D program carried out between 1983 and 1989 at Cadarache nuclear center; full scale tests performed in 1990 on FUCHIA loop at Cadarache including description of the loop using plasma torches to generate CsOH aerosols in a steam - air flow, and preliminary results concerning thermohydraulic and thermic behavior under residual power simulated filtration efficiency with CsOH aerosols and iodine; complementary design, including hydrogen risk during condensation period, radiological shieldings of the filter, and heat removal after the filter closure; and conclusion on the validation of the filter

Adhesion to sand and ability to mineralise low pesticide concentrations are required for efficient bioaugmentation of flow-through sand filters

DEFF Research Database (Denmark)

Samuelsen, Elin Djurhuus; Badawi, Nora; Nybroe, Ole

2017-01-01

(Sphingomonas sp. PM2, Sphingomonas sp. ERG5, Burkholderia sp. TFD34, Cupriavidus sp. TFD38) were characterised with regard to their motility, cell surface hydrophobicity, biofilm formation, adhesion behaviour and ability to mineralise MCPA. Strains PM2 and ERG5 were non-motile and hydrophobic, whilst strains...... TFD34 and TFD38 were motile and less hydrophobic. All the strains except ERG5 showed low biofilm formation on polystyrene, although it was significantly higher on glass. PM2 was the most efficient MCPA degrader as it displayed no lag phase and reached >50 % mineralisation at all concentrations (0.......0016-25 mg L(-1)). PM2 adhered significantly better to sand than the other strains. No link was found between motility, biofilm formation and the ability to adhere to sand. PM2 completely removed MCPA for 14 days when inoculated in sand columns with a constant inlet of 1 mg L(-1) MCPA. These results...

Effect of organic nitrogen concentration on the efficiency of trickling filters

Science.gov (United States)

Kopeć, Łukasz; Drewnowski, Jakub; Fernandez-Morales, F. J.

2018-02-01

The study was conducted in Poland at six selected wastewater treatment plants (WWTP) based on the trickling filters Bioclere® technology. The aim of the study was to find the relationship between the influent organic nitrogen concentration and the purification efficiency expressed as effluent COD concentration. In the tests performed, the COD to BOD5 relationship was close to 2 and the ratio of BOD5 to TN was lower than 4. The research indicated that this specific chemical composition of raw wastewater causes appearance of filamentous bacteria on the surface of trickling filter filling and strongly affect the effluent quality.

Arsenic removal with composite iron matrix filters in Bangladesh: a field and laboratory study.

Science.gov (United States)

Neumann, Anke; Kaegi, Ralf; Voegelin, Andreas; Hussam, Abul; Munir, Abul K M; Hug, Stephan J

2013-05-07

The main arsenic mitigation measures in Bangladesh, well-switching and deep tube wells, have reduced As exposure, but water treatment is important where As-free water is not available. Zero-valent iron (ZVI) based SONO household filters, developed in Bangladesh, remove As by corrosion of locally available inexpensive surplus iron and sand filtration in two buckets. We investigated As removal in SONO filters in the field and laboratory, covering a range of typical groundwater concentrations (in mg/L) of As (0.14-0.96), Fe (0-17), P (0-4.4), Ca (45-162), and Mn (0-2.8). Depending on influent Fe(II) concentrations, 20-80% As was removed in the top sand layer, but As removal to safe levels occurred in the ZVI-layer of the first bucket. Residual As, Fe, and Mn were removed after re-aeration in the sand of the second bucket. New and over 8-year-old filters removed As to iron matrix (CIM) of newer filters and predominantly magnetite in older filters. As mass balances indicated that users filtered less than reported volumes of water, pointing to the need for more educational efforts. All tested SONO filters provided safe drinking water without replacement for up to over 8 years of use.

40 CFR 421.323 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Science.gov (United States)

2010-07-01

....885 Nickel 3.503 2.357 Fluoride 222.900 126.700 (d) Digestion wet air pollution control. BAT... denitration wet air pollution control. BAT Limitations for the Secondary Uranium Subcategory Pollutant or... representing the degree of effluent reduction attainable by the application of the best available technology...

Peat as Substrate for Small-Scale Constructed Wetlands Polishing Secondary Effluents from Municipal Wastewater Treatment Plant

Directory of Open Access Journals (Sweden)

Meng Jin

2017-11-01

Full Text Available With the recent development of constructed wetland technology, it has become a mainstream treatment technology for the mitigation of a variety of wastewaters. This study reports on the treatment performance and pH attenuation capacity of three different configurations of small-scale on-site surface flow constructed wetlands (SFCW: T1 (Peat + Typha latifolia, T2 (T. latifolia alone, and T3 (Peat alone treating secondary effluent from the Amherstview Water Pollution Control Plant (WPCP for two treatment periods (start-up period and operational period. The aim of this study was to compare the nutrients removal efficiencies between the different treatments, as well as to evaluate the effects of substrate and vegetation on the wetland system. For a hydraulic retention time of 2.5 days, the results showed that all treatment systems could attenuate the pH level during both the start-up and operational periods, while significant nutrient removal performance could only be observed during the operational period. Peat was noted to be a better SFCW substrate in promoting the removal of nitrate (NO3-N, total nitrogen (TN, and phosphorus. The addition of T. latifolia further enhanced NO3-N and TN removal efficiencies, but employing T. latifolia alone did not yield effluents that could meet the regulatory discharge limit (1.0 mg/L for phosphorus.

Comparison of six sewage effluents treated with different treatment technologies--population level responses in the harpacticoid copepod Nitocra spinipes.

Science.gov (United States)

Lundström, Elin; Björlenius, Berndt; Brinkmann, Markus; Hollert, Henner; Persson, Jan-Olov; Breitholtz, Magnus

2010-03-01

Since conventional treatment technologies may fail in removing many micro-pollutants, there is currently a focus on the potential of additional treatment technologies for improved sewage treatment. The aim of the present study was to evaluate six different effluents from Henriksdal Sewage Treatment Plant in Stockholm, Sweden. The effluents were; conventionally treated effluent (chemical phosphorous removal in combination with an activated sludge process, including biological nitrogen removal and a sand filter), with additional treatments individually added to the conventional treatment; active carbon filtration, ozonation at 5 mg l(-1), ozonation at 15 mg l(-1), ozonation at 5 mg l(-1)+moving bed biofilm reactor and irradiation with ultraviolet radiation+hydrogen peroxide. The evaluation was done by characterizing and comparing the effluents using a Lefkovitch matrix model based on a life cycle test with the harpacticoid copepod Nitocra spinipes, combined with analysis of juvenile development and survival over time. The conventionally treated effluent resulted in the most negative effects, leading to the conclusion that all additional treatments in the present study created effluents with less negative impacts on the copepod populations. The ozone treatments with the low dose treatment in particular, resulted in the overall least negative effects. Moving bed biofilm reactor combined with ozone did not improve the quality of the effluent in the sense that slightly more negative effects on the population abundance were seen for this treatment technology compared to ozonation alone. The active carbon treatment had more negative effects than the ozone treatments, most of which could possibly be explained by removal of essential metal ions. The effluent which was treated with ultraviolet radiation+hydrogen peroxide resulted in few developmental and survival effects over time, but still showed negative effects on the population level. Matrix population modeling proved a

Comparison of six sewage effluents treated with different treatment technologies-Population level responses in the harpacticoid copepod Nitocra spinipes

Energy Technology Data Exchange (ETDEWEB)

Lundstroem, Elin, E-mail: elin.lundstrom@itm.su.se [Stockholm University, Department of Applied Environmental Science (ITM), S-106 91 Stockholm (Sweden); Bjoerlenius, Berndt [Stockholm Water Company, S-106 36 Stockholm (Sweden); Brinkmann, Markus; Hollert, Henner [RWTH Aachen University, Institute for Environmental Research, Department of Ecosystem Analysis, D-520 74 Aachen (Germany); Persson, Jan-Olov [Stockholm University, Department of Mathematics, S-106 91 Stockholm (Sweden); Breitholtz, Magnus [Stockholm University, Department of Applied Environmental Science (ITM), S-106 91 Stockholm (Sweden)

2010-03-01

Since conventional treatment technologies may fail in removing many micro-pollutants, there is currently a focus on the potential of additional treatment technologies for improved sewage treatment. The aim of the present study was to evaluate six different effluents from Henriksdal Sewage Treatment Plant in Stockholm, Sweden. The effluents were; conventionally treated effluent (chemical phosphorous removal in combination with an activated sludge process, including biological nitrogen removal and a sand filter), with additional treatments individually added to the conventional treatment; active carbon filtration, ozonation at 5 mg l{sup -1}, ozonation at 15 mg l{sup -1}, ozonation at 5 mg l{sup -1} + moving bed biofilm reactor and irradiation with ultraviolet radiation + hydrogen peroxide. The evaluation was done by characterizing and comparing the effluents using a Lefkovitch matrix model based on a life cycle test with the harpacticoid copepod Nitocra spinipes, combined with analysis of juvenile development and survival over time. The conventionally treated effluent resulted in the most negative effects, leading to the conclusion that all additional treatments in the present study created effluents with less negative impacts on the copepod populations. The ozone treatments with the low dose treatment in particular, resulted in the overall least negative effects. Moving bed biofilm reactor combined with ozone did not improve the quality of the effluent in the sense that slightly more negative effects on the population abundance were seen for this treatment technology compared to ozonation alone. The active carbon treatment had more negative effects than the ozone treatments, most of which could possibly be explained by removal of essential metal ions. The effluent which was treated with ultraviolet radiation + hydrogen peroxide resulted in few developmental and survival effects over time, but still showed negative effects on the population level. Matrix population

Peracetic acid (PAA) disinfection of primary, secondary and tertiary treated municipal wastewaters.

Science.gov (United States)

Koivunen, J; Heinonen-Tanski, H

2005-11-01

The efficiency of peracetic acid (PAA) disinfection against enteric bacteria and viruses in municipal wastewaters was studied in pilot-scale. Disinfection pilot-plant was fed with the primary or secondary effluent of Kuopio municipal wastewater treatment plant or tertiary effluent from the pilot-scale dissolved air flotation (DAF) unit. Disinfectant doses ranged from 2 to 7 mg/l PAA in the secondary and tertiary effluents, and from 5 to 15 mg/l PAA in the primary effluents. Disinfection contact times were 4-27 min. Disinfection of secondary and tertiary effluents with 2-7 mg/l PAA and 27 min contact time achieved around 3 log reductions of total coliforms (TC) and enterococci (EC). PAA disinfection also significantly improved the hygienic quality of the primary effluents: 10-15 mg/l PAA achieved 3-4 log reductions of TC and EC, 5 mg/l PAA resulting in below 2 log reductions. F-RNA coliphages were more resistant against the PAA disinfection and around 1 log reductions of these enteric viruses were typically achieved in the disinfection treatments of the primary, secondary and tertiary effluents. Most of the microbial reductions occurred during the first 4-18 min of contact time, depending on the PAA dose and microorganism. The PAA disinfection efficiency remained relatively constant in the secondary and tertiary effluents, despite of small changes of wastewater quality (COD, SS, turbidity, 253.7 nm transmittance) or temperature. The disinfection efficiency clearly decreased in the primary effluents with substantially higher microbial, organic matter and suspended solids concentrations. The results demonstrated that PAA could be a good alternative disinfection method for elimination of enteric microbes from different wastewaters.

Test of active coal capacity for retaining gaseous effluents contaminated by 131 I

International Nuclear Information System (INIS)

Campeanu, Catalina; Cruceru, Madalina; Neacsu, Elena

1999-01-01

The aim of this paper is to test the retaining capacity of the active coal of the filters for gaseous effluents contaminated by 131 I. The active coal filters are design for equipping ventilation installations of nuclear plants in which radioactive iodine and combination of it were produced and handled. Such active coal filters are provided also to sorbonnes for radiochemical and physical handling of radioactive iodine. Testing the retaining capacity of active coal for filters is an obvious step, particularly, when the material was stored long time after preparation

A comparison of the suitability of different willow varieties to treat on-site wastewater effluent in an Irish climate.

Science.gov (United States)

Curneen, S J; Gill, L W

2014-01-15

Short rotation coppiced willow trees can be used to treat on-site wastewater effluent with the advantage that, if planted in a sealed basin and sized correctly, they produce no effluent discharge. This paper has investigated the evapotranspiration rate of four different willow varieties while also monitoring the effects of three different effluent types on each variety. The willow varieties used are all cultivars of Salix viminalis. The effluents applied were primary (septic tank) effluent, secondary treated effluent and rain water (control). The results obtained showed that the addition of effluent had a positive effect on the evapotranspiration. The willows were also found to uptake a high proportion of the nitrogen and phosphorus from the primary and secondary treated effluents added during the first year. The effect of the different effluents on the evapotranspiration rate has been used to design ten full scale on-site treatment systems which are now being monitored. Copyright © 2013 Elsevier Ltd. All rights reserved.

Combining micelle-clay sorption to solar photo-Fenton processes for domestic wastewater treatment.

Science.gov (United States)

Brienza, Monica; Nir, Shlomo; Plantard, Gael; Goetz, Vincent; Chiron, Serge

2018-06-08

A tertiary treatment of effluent from a biological domestic wastewater treatment plant was tested by combining filtration and solar photocatalysis. Adsorption was carried out by a sequence of two column filters, the first one filled with granular activated carbon (GAC) and the second one with granulated nano-composite of micelle-montmorillonite mixed with sand (20:100, w/w). The applied solar advanced oxidation process was homogeneous photo-Fenton photocatalysis using peroxymonosulfate (PMS) as oxidant agent. This combination of simple, robust, and low-cost technologies aimed to ensure water disinfection and emerging contaminants (ECs, mainly pharmaceuticals) removal. The filtration step showed good performances in removing dissolved organic matter and practically removing all bacteria such as Escherichia coli and Enterococcus faecalis from the secondary treated water. Solar advanced oxidation processes were efficient in elimination of trace levels of ECs. The final effluent presented an improved sanitary level with acceptable chemical and biological characteristics for irrigation.

The Suitability of Pozzolan as Admixing Aggregate for Fe0-Based Filters

Directory of Open Access Journals (Sweden)

Arnaud Igor Ndé-Tchoupé

2018-04-01

Full Text Available Continuous gravity-fed column experiments using the methylene blue (MB discoloration method were performed to characterize the suitability of a pozzolan (PZ specimen as alternative admixing aggregate for metallic iron filters (Fe0-filters. Investigated systems were: (i pure sand, (ii pure PZ, (iii pure Fe0, (iv Fe0/sand, (v Fe0/PZ, and (vi Fe0/sand/PZ. The volumetric proportion of Fe0 was 25%. The volumetric proportions of the Fe0/sand/PZ system was 25/45/30. The initial MB concentration was 2.0 mg·L−1, 6.0 g of Fe0 was used, and the experiments lasted for 46 days. The individual systems were fed with 3.9 to 8.4 L (7.80 to 16.69 mg of MB and were characterized by the time-dependent changes of: (i the pH value, (ii the iron breakthrough, (iii the MB breakthrough, and (iv the hydraulic conductivity. Results showed that the Fe0/sand/PZ system was the most efficient. This ternary system was also the most permeable and therefore the most sustainable. The suitability of MB as a powerful operative indicator for the characterization of processes in the Fe0/H2O system was confirmed. The tested PZ is recommended as an alternative material for efficient but sustainable Fe0 filters.

Bacterial community involved in the nitrogen cycle in a down-flow sponge-based trickling filter treating UASB effluent.

Science.gov (United States)

Mac Conell, E F A; Almeida, P G S; Martins, K E L; Araújo, J C; Chernicharo, C A L

2015-01-01

The bacterial community composition of a down-flow sponge-based trickling filter treating upflow anaerobic sludge blanket (UASB) effluent was investigated by pyrosequencing. Bacterial community composition considerably changed along the reactor and over the operational period. The dominant phyla detected were Proteobacteria, Verrucomicrobia, and Planctomycetes. The abundance of denitrifiers decreased from the top to the bottom and it was consistent with the organic matter concentration gradients. At lower loadings (organic and nitrogen loading rates), the abundance of anammox bacteria was higher than that of the ammonium-oxidizing bacteria in the upper portion of the reactor, suggesting that aerobic and anaerobic ammonium oxidation occurred. Nitrification occurred in all the compartments, while anammox bacteria prominently appeared even in the presence of high organic carbon to ammonia ratios (around 1.0-2.0 gCOD gN(-1)). The results suggest that denitrifiers, nitrifiers, and anammox bacteria coexisted in the reactor; thus, different metabolic pathways were involved in ammonium removal in the post-UASB reactor sponge-based.

Fate of dissolved organic nitrogen in two stage trickling filter process.

Science.gov (United States)

Simsek, Halis; Kasi, Murthy; Wadhawan, Tanush; Bye, Christopher; Blonigen, Mark; Khan, Eakalak

2012-10-15

Dissolved organic nitrogen (DON) represents a significant portion of nitrogen in the final effluent of wastewater treatment plants (WWTPs). Biodegradable portion of DON (BDON) can support algal growth and/or consume dissolved oxygen in the receiving waters. The fate of DON and BDON has not been studied for trickling filter WWTPs. DON and BDON data were collected along the treatment train of a WWTP with a two-stage trickling filter process. DON concentrations in the influent and effluent were 27% and 14% of total dissolved nitrogen (TDN). The plant removed about 62% and 72% of the influent DON and BDON mainly by the trickling filters. The final effluent BDON values averaged 1.8 mg/L. BDON was found to be between 51% and 69% of the DON in raw wastewater and after various treatment units. The fate of DON and BDON through the two-stage trickling filter treatment plant was modeled. The BioWin v3.1 model was successfully applied to simulate ammonia, nitrite, nitrate, TDN, DON and BDON concentrations along the treatment train. The maximum growth rates for ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria, and AOB half saturation constant influenced ammonia and nitrate output results. Hydrolysis and ammonification rates influenced all of the nitrogen species in the model output, including BDON. Copyright © 2012 Elsevier Ltd. All rights reserved.

A biocoagulant slow sand filtration for disinfection of Toxoplasma ...

African Journals Online (AJOL)

An integrated low-tech biocoagulant-sand filter drum for disinfection of oocysts of Toxoplasma gondii targeted for developing countries was evaluated. Dirty and turbid water (130.3 NTU) from Mezam River and leachates from dump sites and stagnant water in Bamenda, Cameroon, was analyzed microscopically after ...

Settling and survival profile of enteric pathogens in the swine effluent for water reuse purpose.

Science.gov (United States)

Fongaro, G; Kunz, A; Magri, M E; Schissi, C D; Viancelli, A; Philippi, L S; Barardi, C R M

2016-11-01

The present study evaluated the pathogens persistence and settling profile in swine effluent. We determined the enteric pathogens settling characteristics, their survival and inactivation profile in swine effluent (for water reuse purpose) and in sludge (generated after aerobic treatment - during secondary settling process). The study was performed in laboratorial-scale and in full-scale (manure treatment plant). Enteric viruses and enteric bacteria were used as biomarkers. Results showed that these enteric pathogens were significantly reduced from swine effluent during secondary settling process, and enteric viruses removal was correlated with the suspended solids decantation. The design of secondary settlers can be adapted to improve pathogens removal, by diminishing the solids loading rate per area and time, ending in higher hydraulic retention times. Copyright © 2016 Elsevier GmbH. All rights reserved.

Performance of plastic- and sponge-based trickling filters treating effluents from an UASB reactor.

Science.gov (United States)

Almeida, P G S; Marcus, A K; Rittmann, B E; Chernicharo, C A L

2013-01-01

The paper compares the performance of two trickling filters (TFs) filled with plastic- or sponge-based packing media treating the effluent from an upflow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated with an organic loading rate (OLR) of 1.2 kgCOD m(-3) d(-1), and the OLR applied to the TFs was 0.30-0.65 kgCOD m(-3) d(-1) (COD: chemical oxygen demand). The sponge-based packing medium (Rotosponge) gave substantially better performance for ammonia, total-N, and organic matter removal. The superior TF-Rotosponge performance for NH(4)(+)-N removal (80-95%) can be attributed to its longer biomass and hydraulic retention times (SRT and HRT), as well as enhancements in oxygen mass transfer by dispersion and advection inside the sponges. Nitrogen removals were significant (15 mgN L(-1)) in TF-Rotosponge when the OLRs were close to 0.75 kgCOD m(-3) d(-1), due to denitrification that was related to solids hydrolysis in the sponge interstices. For biochemical oxygen demand removal, higher HRT and SRT were especially important because the UASB removed most of the readily biodegradable organic matter. The new configuration of the sponge-based packing medium called Rotosponge can enhance the feasibility of scaling-up the UASB/TF treatment, including when retrofitting is necessary.

Dissolved organic nitrogen recalcitrance and bioavailable nitrogen quantification for effluents from advanced nitrogen removal wastewater treatment facilities

International Nuclear Information System (INIS)

Fan, Lu; Brett, Michael T.; Jiang, Wenju; Li, Bo

2017-01-01

The objective of this study was to determine the composition of nitrogen (N) in the effluents of advanced N removal (ANR) wastewater treatment plants (WWTPs). This study also tested two different experimental protocols for determining dissolved N recalcitrance. An analysis of 15 effluent samples from five WWTPs, showed effluent concentrations and especially effluent composition varied greatly from one system to the other, with total nitrogen (TN) ranging between 1.05 and 8.10 mg L −1 . Nitrate (NO 3 − ) accounted for between 38 ± 32% of TN, and ammonium accounted for a further 29 ± 28%. All of these samples were dominated by dissolved inorganic nitrogen (DIN; NO 3 −  + NH 4 + ), and uptake experiments indicated the DIN fraction was as expected highly bioavailable. Dissolved organic N (DON) accounted for 20 ± 11% for the total dissolved N in these effluents, and uptake experiments indicated the bioavailability of this fraction varied between 27 ± 26% depending on the WWTP assessed. These results indicate near complete DIN removal should be the primary goal of ANR treatment systems. The comparison of bioavailable nitrogen (BAN) quantification protocols showed that the dissolved nitrogen uptake bioassay approach was clearly a more reliable way to determine BAN concentrations compared to the conventional cell yield protocol. Moreover, because the nitrogen uptake experiment was much more sensitive, this protocol made it easier to detect extrinsic factors (such as biological contamination or toxicity) that could affect the accuracy of these bioassays. Based on these results, we recommend the nitrogen uptake bioassay using filtered and autoclaved samples to quantify BAN concentrations. However, for effluent samples indicating toxicity, algal bioassays will not accurately quantify BAN. - Highlights: • DIN was the dominated N pool for most of the tested effluent samples. • DON bioavailability considerably varied depending on the WWTP assessed. �

BENTONITE-QUARTZ SAND AS THE BACKFILL MATERIALS ON THE RADIOACTIVE WASTE REPOSITORY

Directory of Open Access Journals (Sweden)

Raharjo Raharjo

2010-06-01

Full Text Available An investigation of the contribution of quartz sand in the bentonite mixture as the backfill materials on the shallow land burial of radioactive waste has been done. The experiment objective is to determine the effect of quartz sand in a bentonite mixture with bentonite particle sizes of -20+40, -40+60, and -60+80 mesh on the retardation factor and the uranium dispersion in the simulation of uranium migration in the backfill materials. The experiment was carried out by the fixed bed method in the column filled by the bentonite mixture with a bentonite-to-quartz sand weight percent ratio of 0/100, 25/75, 50/50, 75/25, and 100/0 on the water saturated condition flown by uranyl nitrate solution at concentration (Co of 500 ppm. The concentration of uranium in the effluents in interval 15 minutes represented as Ct was analyzed by spectrophotometer, then using Co and Ct, retardation factor (R and dispersivity ( were determined. The experiment data showed that the bentonite of -60+80 mesh and the quartz sand of -20+40 mesh on bentonite-to-quartz sand with weight percent ratio of 50/50 gave the highest retardation factor and dispersivity of 18.37 and 0.0363 cm, respectively.   Keywords: bentonite, quartz sand, backfill materials, radioactive waste

Optimizing nitrification in biological rapid sand filters: Diagnosing and supplementing micronutrients needed for proper filter performance

DEFF Research Database (Denmark)

Lee, Carson Odell; Wagner, Florian Benedikt; Boe-Hansen, Rasmus

Nitrification is an important biological process commonly used in biological drinking water filters to remove ammonium from drinking water. Recent research has shown that a lack of micronutrients could be limiting the performance of these filters. Because nitrification is a biological process, ca...... to be an important diagnostic tool that could decrease regulatory hurdles, and save time and money....

Tritium effluent removal system

International Nuclear Information System (INIS)

Lamberger, P.H.; Gibbs, G.E.

1978-01-01

An air detritiation system has been developed and is in routine use for removing tritium and tritiated compounds from glovebox effluent streams before they are released to the atmosphere. The system is also used, in combination with temporary enclosures, to contain and decontaminate airborne releases resulting from the opening of tritium containment systems during maintenance and repair operations. This detritiation system, which services all the tritium handling areas at Mound Facility, has played an important role in reducing effluents and maintaining them at 2 percent of the level of 8 y ago. The system has a capacity of 1.7 m 3 /min and has operated around the clock for several years. A refrigerated in-line filtration system removes water, mercury, or pump oil and other organics from gaseous waste streams. The filtered waste stream is then heated and passed through two different types of oxidizing beds; the resulting tritiated water is collected on molecular sieve dryer beds. Liquids obtained from regenerating the dryers and from the refrigerated filtration system are collected and transferred to a waste solidification and packaging station. Component redundancy and by-pass capabilities ensure uninterrupted system operation during maintenance. When processing capacity is exceeded, an evacuated storage tank of 45 m 3 is automatically opened to the inlet side of the system. The gaseous effluent from the system is monitored for tritium content and recycled or released directly to the stack. The average release is less than 1 Ci/day. The tritium effluent can be reduced by isotopically swamping the tritium; this is accomplished by adding hydrogen prior to the oxidizer beds, or by adding water to the stream between the two final dryer beds

Use of G3-DHS Bioreactor for Secondary Treatment of Septic Tank Desludging Wastewater

Directory of Open Access Journals (Sweden)

Izarul Machdar

2016-01-01

Full Text Available Study was done for the use of the third-generation of downflow hanging sponge (G3-DHS bioreactor for secondary treatment of septic tank desludging wastewater. The main objective of this study was to evaluate the prospective system of G3-DHS bioreactor to be applied in Indonesia. During experiment, the G3-DHS bioreactor kept a relatively high dissolved oxygen concentration under natural aeration. At a relatively short hydraulic retention (HRT of 3 h, the G3-DHS bioreactor could remove up to 21% (SD 15% of total COD, 21% (SD = 7% of filtered-COD, 58% (SD = 24% of unfiltered-BOD, and 33% (SD = 24% of ammonium removal. The final effluent had an unfiltered-BOD of only 46 mg.L-1 (SD = 20 mg.L-1 that it was below the Indonesian standard (unfiltered-BOD = 100 mg.L-1 for thresholds of domestic wastewater treatment plants effluent.

Measurement of actinides in samples from effluent air, primary coolant and effluent water of nuclear power stations in the Federal Republic of Germany

International Nuclear Information System (INIS)

Winkler, R.; Hoetzl, H.; Rosner, G.

1977-01-01

Since the middle of 1973 the alpha radioactivity of a number of aerosol filters from the stack monitoring systems of some nuclear power stations, of water effluent samples from all german nuclear power stations and of samples from the primary coolant water of one nuclear power reactor was measured. Essentially, the following procedures of sample preparation for alpha spectrometry of the samples in large area gridded ionization chambers were used; cold ashing of the aerosol samples in 'excited' oxygen, coprecipitation of the alpha emitters from the effluent water samples with iron hydroxide and subsequent cold ashing of the precipitate, and evaporation of the samples from the primary cycle on stainless steel plates. The following transuranium nuclides, or some of them, were found in the samples of the primary coolant and in several aerosol filter samples: Pu-239/240, Pu-238 and/or Am-241, Cm-242 and Cm-244. Cm-242 contributes most to the alpha radioactivity in fresh samples. In the effluent water samples Cm-242, Pu-239/240 and Pu-238 and/or Am-241 were identified in some cases, in one case also Cm-244. Detection limits of the procedures used for the analysis of the above stated transuranium nuclides were in the order of 0,1 fCi per m 3 for the aerosol samples and of 0.2 pCi per 1 for the liquid samples. For the effluent air and water samples in most cases specific activities near the detection limit or somewhat higher were found. On the basis of the measurements, an estimation of the annual actinides releases from nuclear power stations in the Federal Republic of Germany is given

Mapping of industrial effluent on coastal sediments using EDX

CSIR Research Space (South Africa)

Gregory, MA

2003-01-01

Full Text Available isotopes [14], magnetic and rare-earth markers such as Ta and Co [15] and bacterial tracers [16]. Passive tracers are materials/substances already present in the effluent as they leave the factory or treatment works. In the case of ?sludges? from sewage... for industrial waste [1,2]. To date, while EDX has been used to determine the speciation of marine suspended particles [21], monitor the translocation and mixing of fill sands [22] and describe the source and intermixing of sea-floor sediments [23...

Sediment Source Fingerprinting of the Lake Urmia Sand Dunes.

Science.gov (United States)

Ahmady-Birgani, Hesam; Agahi, Edris; Ahmadi, Seyed Javad; Erfanian, Mahdi

2018-01-09

Aeolian sand dunes are continuously being discovered in inner dry lands and coastal areas, most of which have been formed over the Last Glacial Maximum. Presently, due to some natural and anthropogenic implications on earth, newly-born sand dunes are quickly emerging. Lake Urmia, the world's second largest permanent hypersaline lake, has started shrinking, vast lands comprising sand dunes over the western shore of the lake have appeared and one question has been playing on the minds of nearby dwellers: where are these sand dunes coming from, What there was not 15 years ago!! In the present study, the determination of the source of the Lake Urmia sand dunes in terms of the quantifying relative contribution of each upstream geomorphological/lithological unit has been performed using geochemical fingerprinting techniques. The findings demonstrate that the alluvial and the fluvial sediments of the western upstream catchment have been transported by water erosion and they accumulated in the lower reaches of the Kahriz River. Wind erosion, as a secondary agent, have carried the aeolian sand-sized sediments to the sand dune area. Hence, the Lake Urmia sand dunes have been originating from simultaneous and joint actions of alluvial, fluvial and aeolian processes.

Enhanced treatment of secondary municipal wastewater effluent: comparing (biological) filtration and ozonation in view of micropollutant removal, unselective effluent toxicity, and the potential for real-time control.

Science.gov (United States)

Chys, Michael; Demeestere, Kristof; Ingabire, Ange Sabine; Dries, Jan; Van Langenhove, Herman; Van Hulle, Stijn W H

2017-07-01

Ozonation and three (biological) filtration techniques (trickling filtration (TF), slow sand filtration (SSF) and biological activated carbon (BAC) filtration) have been evaluated in different combinations as tertiary treatment for municipal wastewater effluent. The removal of 18 multi-class pharmaceuticals, as model trace organic contaminants (TrOCs), has been studied. (Biological) activated carbon filtration could reduce the amount of TrOCs significantly (>99%) but is cost-intensive for full-scale applications. Filtration techniques mainly depending on biodegradation mechanisms (TF and SSF) are found to be inefficient for TrOCs removal as a stand alone technique. Ozonation resulted in 90% removal of the total amount of quantified TrOCs, but a post-ozonation step is needed to cope with an increased unselective toxicity. SSF following ozonation showed to be the only technique able to reduce the unselective toxicity to the same level as before ozonation. In view of process control, innovative correlation models developed for the monitoring and control of TrOC removal during ozonation, are verified for their applicability during ozonation in combination with TF, SSF or BAC. Particularly for the poorly ozone reactive TrOCs, statistically significant models were obtained that correlate TrOC removal and reduction in UVA 254 as an online measured surrogate parameter.

40 CFR 133.102 - Secondary treatment.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Secondary treatment. 133.102 Section... TREATMENT REGULATION § 133.102 Secondary treatment. The following paragraphs describe the minimum level of effluent quality attainable by secondary treatment in terms of the parameters—BOD5, SS and pH. All...

Determining the Effects of Various Factors on the Effectiveness of Ultrasonic Treatment of Secondary Effluent

Directory of Open Access Journals (Sweden)

Sakineh Haddadi

2007-09-01

Full Text Available Sonochemical degradation which combines destruction of the target compounds by free radical reaction and thermal cleavage is a recent advanced oxidation process (AOP with the potential to be effective for removing low concentrations of organic pollutants from aqueous streams. AOPs typically involve the generation and use of the hydroxyl free radical as a strong oxidant to destroy compounds. The decomposition rate of pollutants by ultrasound depends on various factors. In this study, the effects of pH, initial concentration, hydrogen peroxide addition, and TSS concentration on the decomposition of organics in the secondary effluent have been investigated. COD analysis was taken as the index for organic concentration and two ultrasonic frequencies of 35 kHz and 130 kHz were used for treatment of wastewater samples. Results indicated that increases in organic concentration within the range of 20-60 mg/L would decrease organic removal efficiency from wastewater (p

Biofouling of microfilters at the Savannah River Site F/H-Area Effluent Treatment Facility

International Nuclear Information System (INIS)

McCabe, D.J.; Wiggins, A.W.; Poirier, M.R.; Hazen, T.C.

1991-01-01

The F/H-Effluent Treatment Facility uses state-of-the-art water treatment processes to remove contaminants from low-level radioactive wastewater at the Savannah River Site. The plant replaces seepage basins that were closed to comply with the 1984 amendments to the Resource Conservation and Recovery Act (RCRA). The facility removes both radioactive and nonradioactive contaminants from the effluents orginating from onsite waste management facilities. The unit processes involve filtration, ion exchange, activated carbon absorption, and reverse osmosis. The filtration step is prone to considerable fouling, reducing the overall throughput of the facility. The filters utilized in the process are Norton Ceraflo trademark ceramic microfilters. It was discovered that bacteria were primarily responsible for the severe filter fouling. Inorganic fouling was also observed, but was not normally as severe as the bacterial fouling. The bacteria densities necessary to induce severe fouling were not significantly higher than those often found in surface water streams. Diversion of waste streams containing the highest quantity of bacteria, and various methods of source reduction were implemented, which dramatically improved the filter performance. Addition of aluminum nitrate at low pH further improved the filter performance

Biofouling of microfilters at the Savannah River Site F/H-area effluent treatment facility

International Nuclear Information System (INIS)

McCabe, D.J.; Wiggins, A.W.; Poirier, M.R.; Hazen, T.C.

1992-01-01

The F/H-Effluent Treatment Facility uses state-of-the-art water treatment processes to remove contaminants from low-level radioactive wastewater at the Savannah River Site, The plant replaces seepage basins that were closed to comply with the 1984 amendments to the Resource Conservation and Recovery Act (RCRA). The facility removes both radioactive and nonradioactive contaminants from the effluents originating from onsite waste management facilities. The unit processes involve filtration, ion exchange, activated carbon absorption, and reverse osmosis. The filtration step is prone to considerable fouling, reducing the overall throughput of the facility. The Filters utilized in the process are Norton Ceraflo ceramic microfilters. It was discovered that bacteria were primarily responsible for the severe filter fouling. Inorganic fouling was also observed, but was not normally as severe as the bacterial fouling. The bacteria densities necessary to induce severe fouling were not significantly higher than those often found in surface water streams. Diversion of waste streams containing the highest quantity of bacteria, and various methods of source reduction were implemented, which dramatically unproved the filter performance. Addition of aluminum nitrate at low pH further improved the filter performance. (author)

Pulp and paper mill effluent treatments have differential endocrine-disrupting effects on rainbow trout.

Science.gov (United States)

Orrego, Rodrigo; Guchardi, John; Hernandez, Victor; Krause, Rachelle; Roti, Lucia; Armour, Jeffrey; Ganeshakumar, Mathumai; Holdway, Douglas

2009-01-01

Endocrine disruption (ED) effects due to pulp and paper mill effluents extracts involving different industrial procedures and effluent treatments (nontreated, primary, and secondary treated) were evaluated using immature triploid rainbow trout in a pulse-exposure toxicity experiment. The protocol involved the use of intraperitoneal injection of mill extracts (solid-phase extraction [SPE]) corrected for individual fish weight and included several laboratory standards (steroidal hormones and phytosterols). Biological endpoints at two different levels of biological organization were analyzed (molecular and individual organism). Results indicated that nonsignificant changes were observed in the individual physiological indices represented by condition factor, liver somatic index, and gonad somatic index during the experiment. Significant induction of liver ethoxyresorufin-O-deethylase activity was observed between different effluent treatments and experimental controls. Significant endocrine-disrupting effects at the reproductive level were observed in all effluent treatments involving significant increments in plasma vitellogenin (VTG) levels. Fish exposed to untreated effluent extracts had significantly higher VTG levels compared to fish exposed to primary and secondary treatment effluent extracts, indicating a decrease of the estrogenic effect due to the effluent treatment. The present study has shown that for the Chilean pulp and paper mill SPE extracts evaluated, an endocrine disruption effect was induced in immature triploid rainbow, reaffirming the significant estrogenic effects demonstrated previously in laboratory and field experiments.

Rapid Sand Filtration for Best Practical Treatment of Domestic Wastewater Stabilization Pond Effluent

Science.gov (United States)

Boatright, D. T.; Lawrence, C. H.

1977-01-01

The technical and economic feasibility of constructing and operating a rapid sand filtration sewage treatment system as an adjunct to a waste water stabilization pond is investigated. The study concludes that such units are within the technical and economic constraints of a small community and comply with the EPA criteria. (BT)

40 CFR 421.244 - Standards of performance for new sources.

Science.gov (United States)

2010-07-01

...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Nickel... all times. (c) Acid reclaim leaching belt filter backwash. NSPS for the Secondary Nickel Subcategory...

Behaviour of radioiodine in gaseous effluents

International Nuclear Information System (INIS)

Barry, P.J.

1968-01-01

Because of the different chemical forms in which radioiodine occurs in the gaseous state, it is important when designing efficient filters to know the chemical forms which may be present in the effluent gases when various operations are being carried out and to know the effect of different gaseous environments on the filtration efficiency. To obtain this information it is necessary to have available reliable means of characterizing different chemical forms and to sample gaseous effluents when these operations are being carried out. This paper describes the use for identifying molecular iodine of metallic screens in a multi-component sampling pack in different gaseous environments. Using multi-component sampling packs, the fractionation of iodine nuclides between different chemical forms was measured in the effluent gases escaping from an in-pile test loop in which the fuel was deliberately ruptured by restricting the flow of coolant. Sequential samples were taken for six hours after the rupture and it was possible to follow during this period the individual behaviours of 13 '1I, 133 I and 135 I. Simultaneous samples were also obtained of the noble gases in the effluent gas stream and of the iodine nuclides in the loop coolant. Similar experiments have been carried out with a view to characterizing the different chemical behaviour of radioiodine as it is released from a variety of operations in the nuclear industry including the cutting of fuel sections in metallurgical examination caves and an incinerator. (author)

Monitoring of released radioactive gaseous and liquid effluent at Rokkasho Reprocessing Plant

International Nuclear Information System (INIS)

Oka, M.; Keta, S.; Nagai, S.; Kano, M.; Ishihara, N.; Moriyama, T.; Ogaki, K.; Noda, K.

2009-01-01

Rokkasho Reprocessing Plant (RRP) Rokkasho Reprocessing Plant started its active tests with spent fuel at the end of March 2006. When spent fuels are sheared and dissolved, radioactive gaseous effluent and radioactive liquid effluent such as krypton-85, tritium, etc. are released into the environment. In order to limit the public dose as low as reasonably achievable in an efficient way, RRP removes radioactive material by evaporation, rinsing, filtering, etc., and then releases it through the main stack and the sea discharge pipeline that allow to make dispersion and dilution very efficiently. Also, concerning the radioactive gaseous and liquid effluent to be released into the environment, the target values of annual release have been defined in the Safety Rule based on the estimated annual release evaluated at the safety review of RRP. By monitoring the radioactive material in gaseous exhaust and liquid effluent RRP controls it not to exceed the target values. RRP reprocessed 430 tUpr of spent fuel during Active Test (March 2006 to October 2008). In this report, we report about: The outline of gaseous and liquid effluent monitoring. The amount of radioactive gaseous and liquid effluent during the active test. The performance of removal of radioactive materials in gaseous and liquid effluents. The impact on the public from radioactive effluents during the active test. (author)

Influence green sand system by core sand additions

Directory of Open Access Journals (Sweden)

N. Špirutová

2012-01-01

Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

Facility Effluent Monitoring Plan for the N Reactor

International Nuclear Information System (INIS)

Watson, D.J.; Brendel, D.F.; Shields, K.D.

1991-11-01

A facility effluent monitoring plan is required by the US Department of Energy in DOE Order 5400.1 for any operations that involve hazardous materials and radioactive substances that could impact employee or public safety or the environment. This document is prepared using the specific guidelines identified in A Guide for Preparing Hanford Site Facility Effluent Monitoring Plans, WHC-EP- 0438. This facility effluent monitoring plan assesses effluent monitoring systems and evaluates whether they are adequate to ensure the public health and safety as specified in applicable federal, state, and local requirements. This facility effluent monitoring plan is the first annual report. It shall ensure long-range integrity of the effluent monitoring systems by requiring an update whenever a new process or operation introduces new hazardous materials or significant radioactive materials. This document must be reviewed annually even if there are no operational changes, and it must be updated as a minimum every three years. The primary purpose of the N Reactor Facility Effluent Monitoring Plan (FEMP), during standby, is to ensure that the radioactive effluents are properly monitored and evaluated for compliance with the applicable DOE orders and regulatory agencies at the federal, state, and local levels. A secondary purpose of the FEMP is to ensure that hazardous wastes are not released, in liquid effluents, to the environment even though the potential to do so is extremely low. The FEMP is to provide a monitoring system that collects representative samples in accordance with industry standards, performs analyses within stringent quality control (QC) requirements, and evaluates the data through the use of comparative analysis with the standards and acceptable environmental models

Effect of Lakhara chemical power station (LPTS) effluents on the river Indus water quality

International Nuclear Information System (INIS)

Mahar, R.B.; Memon, H.M.; Khushwar, M.Y.

2000-01-01

The variation of the quality of river Indus water with respect to the seasonal changes, discharge of water and dilution with the effluents of Lakhra Thermal Power Station (LTPS), has been monitored. The studies were focussed on the river Indus water quality before and after mixing the effluents of the power station. The samples were collected monthly from the representative locations of the river Indus, and analyzed for the residues (total, filterable, non-filterable, volatile and fixed), pH, temperature (air and water), conductance, chloride, hardness, alkalinity, dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (BOD) /sub 5/- nitrate, phosphate, sulfate, ammonia, ammonium, silicates, magnesium, potassium, calcium and sodium. The results have been compared with the permissible limits of ECC (European Economic Community) standards for drinking and surface water. (author)

Heterogeneous photocatalysis using TiO2 modified with hydrotalcite and iron oxide under UV-visible irradiation for color and toxicity reduction in secondary textile mill effluent.

Science.gov (United States)

Arcanjo, Gemima Santos; Mounteer, Ann H; Bellato, Carlos Roberto; Silva, Laís Miguelina Marçal da; Brant Dias, Santos Henrique; Silva, Priscila Romana da

2018-04-01

The objective of this study was to evaluate ADMI color removal from a biologically treated textile mill effluent by heterogeneous photocatalysis with UV-visible irradiation (UV-vis) using a novel catalyst composed of TiO 2 supported on hydrotalcite and doped with iron oxide (HT/Fe/TiO 2 ). Simulated biological treatment of solutions of the dyes (50 mg/L) used in the greatest amounts at the mill where the textile effluent was collected resulted in no color removal in reactive dye solutions and about 50% color removal in vat dye solutions, after 96 h, indicating that the secondary effluent still contained a large proportion of anionic reactive dyes. Photocatalytic treatments were carried out with TiO 2 and HT/Fe/TiO 2 of Fe:Ti molar ratios of 0.25, 0.5, 0.75 and 1, with varying catalyst doses (0-3 mg/L), initial pH values (4-10) and UV-vis times (0-6 h). The highest ADMI color removal with unmodified TiO 2 was found at a dose of 2 g/L and pH 4, an impractical pH value for industrial application. The most efficient composite was HT/Fe/TiO 2 1 at pH 10, also at a dose of 2 g/L, which provided more complete ADMI color removal, from 303 to 9 ADMI color units (96%), than unmodified TiO 2 , from 303 to 37 ADMI color units (88%), under the same conditions. Hydroxyl radicals were responsible for the color reduction, since when 2-propanol, an OH scavenger, was added color removal was very low. For this reason, the HT/Fe/TiO 2 1 composite performed better at pH 10, because the higher concentration of hydroxide ions present at higher pH favored hydroxyl radical formation. COD reductions were relatively low and similar, approximately 20% for both catalysts after 6 h under UV-vis, because of the low initial COD (78 mg/L). Secondary effluent toxicity to Daphnia similis (EC 50  = 70.7%) was reduced by photocatalysis with TiO 2 (EC 50  = 95.0%) and the HT/Fe/TiO 2 1 composite (EC 50  = 78.6%). HT/Fe/TiO 2 1 was reused five times and still lowered

Evaluation of the efficiency of peracetic acid in the disinfection of sewage effluents.

Science.gov (United States)

Stampi, S; De Luca, G; Zanetti, F

2001-11-01

Evaluation of the efficiency of peracetic acid in the disinfection of wastewater in a large treatment plant. Over a period of 18 months 30 sample collections were made, each consisting of three samples taken from: raw incoming sewage, secondary effluent (after 10-12 h) and secondary effluent disinfected with 1.5-2 mg l(-1) of peracetic acid (contact time: 20 min). Total coliforms and Escherichia coli declined from 10(7) MPN 100 ml(-1) in the raw sewage to 10(2) in the disinfected effluent and the enterococci fell from 10(6) MPN 100 ml(-1) to 702 MPN 100 ml(-1). The reduction of bacteria increased with the rise in temperature and decreased with the rise in BOD5. Disinfection with peracetic acid reduced levels of faecal contamination by 97%, thus attaining the limit recommended by current Italian law (Escherichia coli disinfection with peracetic acid is easier to manage than other more common methods and the tests performed confirm that from the bacteriological point of view good results can be obtained for urban effluents.

40 CFR 421.245 - Pretreatment standards for existing sources.

Science.gov (United States)

2010-07-01

...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Nickel... Nickel 9.590 6.344 (c) Acid reclaim leaching belt filter backwash PSES for the Secondary Nickel...

Abundance and composition of indigenous bacterial communities in a multi-step biofiltration-based drinking water treatment plant.

Science.gov (United States)

Lautenschlager, Karin; Hwang, Chiachi; Ling, Fangqiong; Liu, Wen-Tso; Boon, Nico; Köster, Oliver; Egli, Thomas; Hammes, Frederik

2014-10-01

Indigenous bacterial communities are essential for biofiltration processes in drinking water treatment systems. In this study, we examined the microbial community composition and abundance of three different biofilter types (rapid sand, granular activated carbon, and slow sand filters) and their respective effluents in a full-scale, multi-step treatment plant (Zürich, CH). Detailed analysis of organic carbon degradation underpinned biodegradation as the primary function of the biofilter biomass. The biomass was present in concentrations ranging between 2-5 × 10(15) cells/m(3) in all filters but was phylogenetically, enzymatically and metabolically diverse. Based on 16S rRNA gene-based 454 pyrosequencing analysis for microbial community composition, similar microbial taxa (predominantly Proteobacteria, Planctomycetes, Acidobacteria, Bacteriodetes, Nitrospira and Chloroflexi) were present in all biofilters and in their respective effluents, but the ratio of microbial taxa was different in each filter type. This change was also reflected in the cluster analysis, which revealed a change of 50-60% in microbial community composition between the different filter types. This study documents the direct influence of the filter biomass on the microbial community composition of the final drinking water, particularly when the water is distributed without post-disinfection. The results provide new insights on the complexity of indigenous bacteria colonizing drinking water systems, especially in different biofilters of a multi-step treatment plant. Copyright © 2014 Elsevier Ltd. All rights reserved.

Elimination of viruses, bacteria and protozoan oocysts by slow sand filtration

NARCIS (Netherlands)

Hijnen, W.A.M.; Visser, Ate; Schijven, J.F.; Bonné, P.; Medema, Gerriet Jan

2004-01-01

The decimal elimination capacity (DEC) of slow sand filters (SSF) for viruses, bacteria and oocysts of Cryptosporidium has been assessed from full-scale data and pilot plant and laboratory experiments. DEC for viruses calculated from experimental data with MS2-bacteriophages in the pilot plant

Removing Pathogens Using Nano-Ceramic-Fiber Filters

Science.gov (United States)

Tepper, Frederick; Kaledin, Leonid

2005-01-01

A nano-aluminum-oxide fiber of only 2 nanometers in diameter was used to develop a ceramic-fiber filter. The fibers are electropositive and, when formulated into a filter material (NanoCeram(TradeMark)), would attract electro-negative particles such as bacteria and viruses. The ability to detect and then remove viruses as well as bacteria is of concern in space cabins since they may be carried onboard by space crews. Moreover, an improved filter was desired that would polish the effluent from condensed moisture and wastewater, producing potable drinking water. A laboratory- size filter was developed that was capable of removing greater than 99.9999 percent of bacteria and virus. Such a removal was achieved at flow rates hundreds of times greater than those through ultraporous membranes that remove particles by sieving. Because the pore size of the new filter was rather large as compared to ultraporous membranes, it was found to be more resistant to clogging. Additionally, a full-size cartridge is being developed that is capable of serving a full space crew. During this ongoing effort, research demonstrated that the filter media was a very efficient adsorbent for DNA (deoxyribonucleic acid), RNA (ribonucleic acid), and endotoxins. Since the adsorption is based on the charge of the macromolecules, there is also a potential for separating proteins and other particulates on the basis of their charge differences. The separation of specific proteins is a major new thrust of biotechnology. The principal application of NanoCeram filters is based on their ability to remove viruses from water. The removal of more than 99.9999 percent of viruses was achieved by a NanoCeram polishing filter added to the effluent of an existing filtration device. NanoCeram is commercially available in laboratory-size filter discs and in the form of a syringe filter. The unique characteristic of the filter can be demonstrated by its ability to remove particulate dyes such as Metanyl yellow. Its

Seasonal occurrence, removal efficiencies and preliminary risk assessment of multiple classes of organic UV filters in wastewater treatment plants.

Science.gov (United States)

Tsui, Mirabelle M P; Leung, H W; Lam, Paul K S; Murphy, Margaret B

2014-04-15

Organic ultraviolet (UV) filters are applied widely in personal care products (PCPs), but the distribution and risks of these compounds in the marine environment are not well known. In this study, the occurrence and removal efficiencies of 12 organic UV filters in five wastewater treatment plants (WWTPs) equipped with different treatment levels in Hong Kong, South China, were investigated during one year and a preliminary environmental risk assessment was carried out. Using a newly developed simultaneous multiclass quantification liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, butyl methoxydibenzoylmethane (BMDM), 2,4-dihydroxybenzophenone (BP-1), benzophenone-3 (BP-3), benzophenone-4 (BP-4) and 2-ethyl-hexyl-4-trimethoxycinnamate (EHMC) were frequently (≥80%) detected in both influent and effluent with mean concentrations ranging from 23 to 1290 ng/L and 18-1018 ng/L, respectively; less than 2% of samples contained levels greater than 1000 ng/L. Higher concentrations of these frequently detected compounds were found during the wet/summer season, except for BP-4, which was the most abundant compound detected in all samples in terms of total mass. The target compounds behaved differently depending on the treatment level in WWTPs; overall, removal efficiencies were greater after secondary treatment when compared to primary treatment with >55% and compounds showing high removal (defined as >70% removal), respectively. Reverse osmosis was found to effectively eliminate UV filters from effluent (>99% removal). A preliminary risk assessment indicated that BP-3 and EHMC discharged from WWTPs may pose high risk to fishes in the local environment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Journal of Civil Engineering Research and Practice - Vol 4, No 1 ...

African Journals Online (AJOL)

In-Plane Shear Response of Externally Bonded CFRP on Autoclaved Aerated Concrete · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD ... Improvement of WSP Effluent Quality for Reuse using Intermittent Slow Sand Filter – The Egerton WSP Pilot Study. P. W. Murage, G. M. Thumbi, D. K. ...

Evaluation of effluents from bench-scale treatment combinations for landfill leachate in Ibadan, Nigeria.

Science.gov (United States)

Aluko, Olufemi Oludare; Sridhar, Mkc

2014-01-01

The removal of pollutants in landfill leachate was investigated using constructed wetlands, a trickling filter, alum flocculation and coagulation, and a sequencing batch reactor in various combinations. Thirteen combined operations were investigated involving three out of the four unit treatment methods in series. The study was conducted because unit operations, though achieved reductions in pollutants concentrations had effluent values above the national regulatory guideline values. The suspended solids of effluents were permissible in most treatment processes, while reductions in 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and ammonia (NH3) of leachates ranged from 80% to 97%; 86% to 97% and 92% to 98% respectively. However, there were significant increases in nitrate (85%) and dissolved oxygen of treatment (218%). In addition, the characteristics of the recommended treatment sequence, involving constructed wetlands, alum and trickling filter produced effluents with reductions in colour (97%), alkalinity (97%), BOD (97%), COD (97%) and NH3 (98%), and in metals, except nickel (29% reduction from the influent values). The recommended treatment combination is suitable for effective leachate management at the landfill. The cost of constructing and operating the recommended treatment combination at the facility, for 5 years, would be NGN6,009,750.00 ($38,036.39). The performance should be monitored on site prior to full adoption if effluent characteristics remain consistently low over dry and wet seasons.

Modelling of a sand bed filter in the cell exhaust air pathway

International Nuclear Information System (INIS)

Schmid, M.

1983-01-01

Sandbed filters are appropriate incident filters for zircaloy fires, dissolver fires, and explosions. The alternative treatment of these incidents with and without SBF can thus also quantify the safety gain if an SBF is used. The SBF is considered to be a pure incident filter and according to a planning the SBF is by-passed during normal operation. In case of a temperature rise in the cell the by-pass is blocked by a fire protection valve. (orig./DG) [de

A study on the characteristics of the flow distribution in the Module Ceramic Filter during filter cleaning

International Nuclear Information System (INIS)

Chung, Jin-Do; Kim, Jang-Woo; Chung, Hwi-Bok; Im, Byoung-Uk; Chung, Eun-Ho; Yoon, Sang-Wook

2010-01-01

Ceramic filter has demonstrated as an attractive system to improve the efficiency and to reduce the effluent pollutants. Removal of particulates from the hot gas stream is very important in air pollution control. In particular, the elimination of the particulate matters discharged from a gas turbine at high temperature can prevent the corrosion the Integrated Gasification Combined Cycle. In this study, a Lab. scale test and numerical simulation were carried out to comprehend the relationship between pulse jet pressure and recovery of pressure drop and to characterize the reverse cleaning flow through a ceramic filter. (author)

Efficiency of advanced wastewater treatment technologies for the reduction of hormonal activity in effluents and connected surface water bodies by means of vitellogenin analyses in rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta f. fario).

Science.gov (United States)

Henneberg, Anja; Triebskorn, Rita

2015-01-01

Endocrine effects in the aquatic environment are in the focus of scientists and media along with debates on the necessity of further steps in wastewater treatment. In the present study VTG responses were compared to evaluate upgrades at wastewater treatment plants (WWTPs). We investigated several advanced sewage treatment technologies at two WWTPs connected to the Schussen, a tributary of Lake Constance, for the reduction of hormonal activity: (1) a powdered activated charcoal filter at the WWTP Langwiese; and (2) a combination of ozonation, sand filter, and granulated activated carbon filter at the WWTP Eriskirch. Rainbow trout and brown trout were either directly exposed to the effluents in aquaria or cages, or in a bypass system flown through by surface water of the Schussen. As a reference, trout were kept in bypass aquaria at the Argen River, which is less influenced by micropollutants. As a biomarker for estrogenicity, we analyzed the yolk precursor protein vitellogenin in immature rainbow trout and brown trout and in trout larvae (100 days post-fertilization) prior to and after the upgrade with the new technologies. Trout of different ages and species were used to detect differences in their sensitivity. At both bypass stations, larvae of brown trout showed significantly higher vitellogenin levels prior to the upgrade compared to negative control levels. Female brown trout exposed at the bypass station downstream of the WWTP showed decreased vitellogenin levels after the upgrade. In 1-year-old immature trout directly exposed to the respective effluents, no significant effects of the upgrades on vitellogenin levels were found. In general, larger effects were observed in brown trout than in rainbow trout, indicating that they are more sensitive test organisms.

Modelling the removal of p-TSA (para-toluenesulfonamide) during rapid sand filtration used for drinking water treatment.

Science.gov (United States)

Meffe, Raffaella; Kohfahl, Claus; Holzbecher, Ekkehard; Massmann, Gudrun; Richter, Doreen; Dünnbier, Uwe; Pekdeger, Asaf

2010-01-01

A finite element model was set-up to determine degradation rate constants for p-TSA during rapid sand filtration (RSF). Data used for the model originated from a column experiment carried out in the filter hall of a drinking water treatment plant in Berlin (Germany). Aerated abstracted groundwater was passed through a 1.6m long column-shaped experimental sand filter applying infiltration rates from 2 to 6mh(-1). Model results were fitted to measured profiles and breakthrough curves of p-TSA for different infiltration rates using both first-order reaction kinetics and Michaelis-Menten kinetics. Both approaches showed that degradation rates varied both in space and time. Higher degradation rates were observed in the upper part of the column, probably related to higher microbial activity in this zone. Measured and simulated breakthrough curves revealed an adaption phase with lower degradation rates after infiltration rates were changed, followed by an adapted phase with more elevated degradation rates. Irrespective of the mathematical approach and the infiltration rate, degradation rates were very high, probably owing to the fact that filter sands have been in operation for decades, receiving high p-TSA concentrations with the raw water.

Compositional Signatures in Acoustic Backscatter Over Vegetated and Unvegetated Mixed Sand-Gravel Riverbeds

Science.gov (United States)

Buscombe, D.; Grams, P. E.; Kaplinski, M. A.

2017-10-01

Multibeam acoustic backscatter has considerable utility for remote characterization of spatially heterogeneous bed sediment composition over vegetated and unvegetated riverbeds of mixed sand and gravel. However, the use of high-frequency, decimeter-resolution acoustic backscatter for sediment classification in shallow water is hampered by significant topographic contamination of the signal. In mixed sand-gravel riverbeds, changes in the abiotic composition of sediment (such as homogeneous sand to homogeneous gravel) tend to occur over larger spatial scales than is characteristic of small-scale bedform topography (ripples, dunes, and bars) or biota (such as vascular plants and periphyton). A two-stage method is proposed to filter out the morphological contributions to acoustic backscatter. First, the residual supragrain-scale topographic effects in acoustic backscatter with small instantaneous insonified areas, caused by ambiguity in the local (beam-to-beam) bed-sonar geometry, are removed. Then, coherent scales between high-resolution topography and backscatter are identified using cospectra, which are used to design a frequency domain filter that decomposes backscatter into the (unwanted) high-pass component associated with bedform topography (ripples, dunes, and sand waves) and vegetation, and the (desired) low-frequency component associated with the composition of sediment patches superimposed on the topography. This process strengthens relationships between backscatter and sediment composition. A probabilistic framework is presented for classifying vegetated and unvegetated substrates based on acoustic backscatter at decimeter resolution. This capability is demonstrated using data collected from diverse settings within a 386 km reach of a canyon river whose bed varies among sand, gravel, cobbles, boulders, and submerged vegetation.

Compositional signatures in acoustic backscatter over vegetated and unvegetated mixed sand-gravel riverbeds

Science.gov (United States)

Buscombe, Daniel; Grams, Paul E.; Kaplinski, Matt A.

2017-01-01

Multibeam acoustic backscatter has considerable utility for remote characterization of spatially heterogeneous bed sediment composition over vegetated and unvegetated riverbeds of mixed sand and gravel. However, the use of high-frequency, decimeter-resolution acoustic backscatter for sediment classification in shallow water is hampered by significant topographic contamination of the signal. In mixed sand-gravel riverbeds, changes in the abiotic composition of sediment (such as homogeneous sand to homogeneous gravel) tend to occur over larger spatial scales than is characteristic of small-scale bedform topography (ripples, dunes, and bars) or biota (such as vascular plants and periphyton). A two-stage method is proposed to filter out the morphological contributions to acoustic backscatter. First, the residual supragrain-scale topographic effects in acoustic backscatter with small instantaneous insonified areas, caused by ambiguity in the local (beam-to-beam) bed-sonar geometry, are removed. Then, coherent scales between high-resolution topography and backscatter are identified using cospectra, which are used to design a frequency domain filter that decomposes backscatter into the (unwanted) high-pass component associated with bedform topography (ripples, dunes, and sand waves) and vegetation, and the (desired) low-frequency component associated with the composition of sediment patches superimposed on the topography. This process strengthens relationships between backscatter and sediment composition. A probabilistic framework is presented for classifying vegetated and unvegetated substrates based on acoustic backscatter at decimeter resolution. This capability is demonstrated using data collected from diverse settings within a 386 km reach of a canyon river whose bed varies among sand, gravel, cobbles, boulders, and submerged vegetation.

40 CFR 421.315 - Pretreatment standards for existing sources.

Science.gov (United States)

2010-07-01

...) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Tungsten....346 68.543 Tungsten 197.1 87.8 (k) Cobalt hydroxide filter cake wash. PSES for the Secondary Tungsten...

Assessment of the capacity of slow sand filtration to eliminate Cryptosporidium oocysts

NARCIS (Netherlands)

Hijnen, W.A.M.; Dullemont, Y.J.; Bosklopper, K.T.G.J.; Schijven, J.F.; Medema, Gerriet Jan

2006-01-01

Decimal Elimination Capacity (DEC) of the slow sand filters of the Dutch drinking water Companies was assessed; first by literature review, followed by evaluation of the removal of environmental spores of sulphite-reducing clostridia (SSRC) and small-sized centric diatoms (SSCD) as surrogates.

Unconfined Groundwater Dispersion Model On Sand Layers In Coral Island

OpenAIRE

Sultan

2016-01-01

The research objective is to analyze the sand layer to determine the characteristics of the unconfined groundwater aquifer on coral island and found the dispersion model of unconfined groundwater in the sand layer in the coral island. The method used is direct research in the field, laboratory analysis and secondary data. Observations geological conditions, as well as the measurement and interpretation of geoelectrical potential groundwater models based on the value of the conductivity of gro...

Criticality safety evaluation report for K Basin filter cartridges

International Nuclear Information System (INIS)

Schwinkendorf, K.N.

1995-01-01

A criticality safety evaluation of the K Basin filter cartridge assemblies has been completed to support operations without a criticality alarm system. The results show that for normal operation, the filter cartridge assembly is far below the safety limit of k eff = 0.95, which is applied to plutonium systems at the Hanford Site. During normal operating conditions, uranium, plutonium, and fission and corrosion products in solution are continually accumulating in the available void spaces inside the filter cartridge medium. Currently, filter cartridge assemblies are scheduled to be replaced at six month intervals in KE Basin, and at one year intervals in KW Basin. According to available plutonium concentration data for KE Basin and data for the U/Pu ratio, it will take many times the six-month replacement time for sufficient fissionable material accumulation to take place to exceed the safety limit of k eff = 0.95, especially given the conservative assumption that the presence of fission and corrosion products is ignored. Accumulation of sludge with a composition typical of that measured in the sand filter backwash pit will not lead to a k eff = 0.95 value. For off-normal scenarios, it would require at least two unlikely, independent, and concurrent events to take place before the k eff = 0.95 limit was exceeded. Contingencies considered include failure to replace the filter cartridge assemblies at the scheduled time resulting in additional buildup of fissionable material, the loss of geometry control from the filter cartridge assembly breaking apart and releasing the individual filter cartridges into an optimal configuration, and concentrations of plutonium at U/Pu ratios less than measured data for KE Basin, typically close to 400 according to extensive measurements in the sand filter backwash pit and plutonium production information

Evaluation of wastewater reclamation technologies based on in vitro and in vivo bioassays

International Nuclear Information System (INIS)

Cao Nan; Yang Min; Zhang Yu; Hu Jianying; Ike, Michihiko; Hirotsuji, Junji; Matsui, Hisae; Inoue, Daisuke; Sei, Kazunari

2009-01-01

When municipal secondary effluent is used as the main supplementation water source for surface water bodies, its potential adverse ecological effects should not be neglected. The objective of this work was to investigate the effectiveness of several technologies, i.e. combination of coagulation and sand filtration (CSF), ultraviolet (UV) irradiation, chlorination, ozonation, ultrafiltration (UF) and reverse osmosis filtration (RO), on the removal of acute ecotoxicity, genotoxicity and retinoic acid receptor (RAR) agonist activity from the municipal secondary effluent. The effects of treated effluents on the development of Japanese medaka (Oryzias latipes) embryos were also evaluated. The secondary effluent exhibited a mutagenic effect on Salmonella typhimurium strain TA 1535/pSK1002, acute invertebrate toxicity to Daphnia magna, and weak RAR α activity. RO and ozonation demonstrated remarkable removals of the genotoxic effect, acute toxicity and RAR activity from secondary effluent, while chlorination could elevate both genotoxicity and acute toxicity. CSF, UV, UF, chlorination as well as RO could decrease the 4-day mortality of medaka embryos and accordingly increase the hatching success rate, comparing with the secondary effluent. Ozonation at 4 mg/l and higher doses, however, elicited significantly higher 4-day mortality, leading to the reduction of the hatching success rate

A Randomized Controlled Trial of the Plastic-Housing BioSand Filter and Its Impact on Diarrheal Disease in Copan, Honduras

Science.gov (United States)

Fabiszewski de Aceituno, Anna M.; Stauber, Christine E.; Walters, Adam R.; Meza Sanchez, Rony E.; Sobsey, Mark D.

2012-01-01

Point of use drinking water treatment with the BioSand filter (BSF) allows people to treat their water in the home. The purpose of this research was to document the ability of the Hydraid plastic-housing BSF to reduce diarrheal disease in households who received a BSF in a randomized controlled trial. The trial of the Hydraid plastic-housing BSF was carried out in rural, mountainous communities in Copan, Honduras during April of 2008 to February of 2009. A logistic regression adjusting for clustering showed that the incidence of diarrheal disease in children under 5 years was reduced by approximately 45% (odds ratio = 0.55, 95% confidence interval = 0.28, 1.10) in households that had a BSF compared with those households without a BSF, but this finding fluctuated depending on season and was not statistically significant. Households with a BSF had significantly better drinking water quality regardless of water source or season. PMID:22665593

Pollution patterns and underlying relationships of benzophenone-type UV-filters in wastewater treatment plants and their receiving surface water.

Science.gov (United States)

Wu, Ming-Hong; Li, Jian; Xu, Gang; Ma, Luo-Dan; Li, Jia-Jun; Li, Jin-Song; Tang, Liang

2018-05-15

The environmental behaviors of emerging pollutants, benzophenone-type UV filters (BP-UV filters) and their derivatives were investigated in four wastewater treatment plants (WWTPs), and their receiving surface waters in Shanghai. The concentration level of selected BP-UV filters in the WWTPs was detected from ngL -1 to μgL -1 . BP (621-951ngL -1 ) and BP-3 (841-1.32 × 10 3 ngL -1 ) were the most abundant and highest detection frequency individuals among the target BP-UV filters in influents, whereas BP (198-400ngL -1 ), BP-4 (93.3-288ngL -1 ) and BP-3 (146-258ngL -1 ) were predominant in effluents. BP-UV filters cannot be completely removed and the total removal efficiency varied widely (-456% to 100%) during the treatment process. It can be inferred that the usage of BP and BP-3 are higher than other BP-UV filters in the study area. The lowest and highest levels were BP-2 (ND-7.66ngL -1 ) and BP-3 (68.5-5.01 × 10 3 ng L -1 ) in the receiving surface water, respectively. Interestingly, the seasonal variation of BP-3 is larger than those of other BP-UV filters in surface water from Shanghai. There is no obvious pollution pattern of BP-UV filters in the surface water from the cosmetic factory area. The correlation analysis of BP-UV filters between WWTPs effluents and nearby downstream water samples suggested that BP-UV filters emitted from some WWTPs might be the main source of receiving surface water. Preliminary risk assessment indicated that the levels of BP-UV filters detected by the effluent posed medium to high risk to fish as well as other aquatic organisms. Copyright © 2018 Elsevier Inc. All rights reserved.

Food irradiation dosimetry using thermoluminescence of quartz sand

International Nuclear Information System (INIS)

Khan, H.M.; Ehlermann, D.A.E.

1993-01-01

Thermoluminescence of quartz sand, which is inert and concomitant to several food materials, has been investigated for applications in food irradiation dosimetry and detection of irradiated foods. The glow curves consist of at least three overlapping peaks from 100 to 420 C. The peak at lower temperature is not stable and decays quickly at room temperature. However, the peaks at higher temperature are stable and more useful for dosimetry work. The intensity of the peak at 360 C, measured using different optical filters, shows a linear response in the range of 0.05 to 23 kGy. Stability of these signals at different annealing temperatures has been investigated. Thermoluminescence from adhering minerals and contaminating dust in different food materials has been found useful for the detection of irradiation treatment. Since quartz is frequently one of these minerals, further computerized deconvolution of individual glow peaks from the complex glow curves of quartz sand was carried out which improves the dosimetric results. Possible applications of thermoluminescence of quartz sand in food irradiation dosimetry and detection of irradiated foods have been discussed. (orig.)

Comparative Inactivation of Murine Norovirus and MS2 Bacteriophage by Peracetic Acid and Monochloramine in Municipal Secondary Wastewater Effluent.

Science.gov (United States)

Dunkin, Nathan; Weng, ShihChi; Schwab, Kellogg J; McQuarrie, James; Bell, Kati; Jacangelo, Joseph G

2017-03-07

Chlorination has long been used for disinfection of municipal wastewater (MWW) effluent while the use peracetic acid (PAA) has been proposed more recently in the United States. Previous work has demonstrated the bactericidal effectiveness of PAA and monochloramine in wastewater, but limited information is available for viruses, especially ones of mammalian origin (e.g., norovirus). Therefore, a comparative assessment was performed of the virucidal efficacy of PAA and monochloramine against murine norovirus (MNV) and MS2 bacteriophage in secondary effluent MWW and phosphate buffer (PB). A suite of inactivation kinetic models was fit to the viral inactivation data. Predicted concentration-time (CT) values for 1-log 10 MS2 reduction by PAA and monochloramine in MWW were 1254 and 1228 mg-min/L, respectively. The 1-, 2-, and 3-log 10 model predicted CT values for MNV viral reduction in MWW were 32, 47, and 69 mg-min/L for PAA and 6, 13, and 28 mg-min/L for monochloramine, respectively. Wastewater treatment plant disinfection practices informed by MS2 inactivation data will likely be protective for public health but may overestimate CT values for reduction of MNV. Additionally, equivalent CT values in PB resulted in greater viral reduction which indicate that viral inactivation data in laboratory grade water may not be generalizable to MWW applications.

Product evaluation phase 1 report

International Nuclear Information System (INIS)

Fairhall, G.A.

1984-01-01

This report concerns the intermediate-level radioactive waste arisings from the reprocessing of irradiated nuclear fuel at BNFL Sellafield. The site ion exchange effluent plant will remove Cs and Sr from active liquid effluents using Mud Hills clinoptilolite. Approximately 40 to 50 m 3 of spent ion exchanger will be generated each year together with 7.5 m 3 of filter sand. Headings are: introduction; characterisation; initial evaluation of potential matrices for encapsulation of waste in form suitable for disposal; waste simulation. (U.K.)

Characteristics and treatment mechanism of mine water with high concentration of iron and manganese

Energy Technology Data Exchange (ETDEWEB)

Li, F.; Yang, J.; He, X.; Yang, J.; Tian, T. [Hebei University of Engineering, Handan (China)

2006-12-15

The characteristics and treatment of mine water with high concentration or iron and manganese were studied with mine water produced in Jiukuang and Siwan belonging to Hebi Coal Industry Group Co., Ltd. Analysis shows that the mine water is abundant in dissolved oxygen and has high TDS and high turbidity so the mine water does not need aeration. The effect of removal of iron and manganese by coagulation-sedimentation and the influence of filter material and influent water flow rate on effluent quality were investigated. It is shown that the removal rate of iron can reach 90% while removal of manganese can only reach about 20%. The concentration of iron and manganese in the effluent is lower than 0.1 mg/L with filter material of manganese sand which was immersed in KMnO{sub 4} solution at a filtration rate of 7 - 9 m/h. The results show that the layer of activated compound substance membrane formed on the surface of the manganese sand plays an important role in the removal of manganese. 7 refs., 2 figs., 3 tabs.

Literature search on the environmental impacts of tar sands operations

International Nuclear Information System (INIS)

Birkholz, D.; Prendergast, S.

1990-09-01

An extensive review is presented of the literature on the chemistry and biological impacts of current and potential effluents and discharges from oil sands plants on the Athabasca River. The pollutant compounds of interest included polycyclic aromatic hydrocarbons, methyl homologues and metabolites, polycyclic aromatic sulfur heterocycles, polycyclic aromatic nitrogen heterocycles, and naphthenic acids. Topics of interest include chemical methods for identifying and quantitating the above compounds and their metabolites, their sources and release rates, their toxicity to native fish of the Athabasca system, and their degradation in the natural environment. 376 refs., 4 figs., 26 tabs

Helmint eggs elimination performance during lammelar settling and sand filters in Beniel WWTP (Murcia, Spain); Rendimiento en la eliminacion de huevos de helminto en la decantacion lamelar y filtracion por arena en la EDAR de Beniel (Murcia)

Energy Technology Data Exchange (ETDEWEB)

Simon Andreu, P. J.; Cardin Mifsut, C.; Pacheco Ballarin, S.; Martinez Muro, M. A.; Vicente Gonzalez, J. A.; Llosar Llacer, C.

2010-07-01

With this study, it was observed Ascaris suum eggs elimination yield of tertiary treatment in Beniel wastewater treatment plant (WWTP) in Murcia Region (Spain). It was inoculated a sample of Ascaris suum eggs in the treatment in maximum flow conditions and it was calculated the retention yield of the lamellar settling and sand filters. (Author) 3 refs.

Optimizing nitrate removal in woodchip beds treating aquaculture effluents

DEFF Research Database (Denmark)

von Ahnen, Mathis; Pedersen, Per Bovbjerg; Hoffmann, Carl Christian

2016-01-01

Nitrate is typically removed from aquaculture effluents using heterotrophic denitrification reactors. Heterotrophic denitrification reactors, however, require a constant input of readily available organic carbon (C) sources which limits their application in many aquaculture systems for practical...... and/or economic reasons.A potential alternative technology for removing nitrate currently applied for treating surface and drainage water is based on using wood by-products as a carbon source for denitrification. Using lab-scale horizontal-flow woodchip filters, the current study investigated...... the potential of optimizing woodchip reactors for treating aquaculture effluent. A central composite design (CCD) was applied to assess the effects of simultaneously changing the empty bed contact time (EBCTs of 5.0-15.0 h; corresponding to theoretical hydraulic retention times of 3.3-9.9 h) and bicarbonate...

Removal of novel antiandrogens identified in biological effluents of domestic wastewater by activated carbon.

Science.gov (United States)

Ma, Dehua; Chen, Lujun; Liu, Rui

2017-10-01

Environmental antiandrogenic (AA) contaminants in effluents from wastewater treatment plants have the potential for negative impacts on wildlife and human health. The aim of our study was to identify chemical contaminants with likely AA activity in the biological effluents and evaluate the removal of these antiandrogens (AAs) during advanced treatment comprising adsorption onto granular activated carbon (GAC). In this study, profiling of AA contaminants in biological effluents and tertiary effluents was conducted using effect-directed analysis (EDA) including high performance liquid chromatography (HPLC) fractionation, a recombinant yeast screen containing androgen receptor (YAS), in combination with mass spectrometry analyses. Analysis of a wastewater secondary effluent from a membrane bioreactor revealed complex profiles of AA activity comprising 14 HPLC fractions and simpler profiles of GAC effluents with only 2 to 4 moderately polar HPLC fractions depending on GAC treatment conditions. Gas chromatography-mass spectrometry and ultra-high performance liquid chromatography-nanospray mass spectrometry analyses of AA fractions in the secondary effluent resulted in detection of over 10 chemical contaminants, which showed inhibition of YAS activity and were potential AAs. The putative AAs included biocides, food additives, flame retardants, pharmaceuticals and industrial contaminants. To our knowledge, it is the first time that the AA properties of N-ethyl-2-isopropyl-5-methylcyclohexanecarboxamide (WS3), cetirizine, and oxcarbazepine are reported. The EDA used in this study was proven to be a powerful tool to identify novel chemical structures with AA activity in the complex aquatic environment. The adsorption process to GAC of all the identified antiandrogens, except WS3 and triclosan, fit well with the pseudo-second order kinetics models. Adsorption to GAC could further remove most of the AAs identified in the biological effluents with high efficiencies. Copyright

Regenerative-filter-incinerator device

Energy Technology Data Exchange (ETDEWEB)

Rosebrock, T.L.

1977-10-18

A regenerative-filter-incinerator device, for use in the exhaust system of a diesel engine, includes a drum-like regenerative-heat exchanger-filter assembly rotatably mounted within a housing that is adapted to be installed directly in the exhaust gas stream discharged from a diesel engine as close to the engine as possible. The regenerative-heat exchanger-filter assembly provides an inner chamber which serves as a reaction chamber for the secondary combustion of exhaust gases including particulates discharged from the engine. The regenerative-heat exchanger-filter assembly includes separately rotatable heat exchange-filter elements pervious to radial flow of fluid therethrough and adapted to filter out particulates from the exhaust gases and to carry them into the reaction chamber. During engine operation, the reaction chamber is provided with a quantity of heat, as necessary, to effect secondary combustion of the exhaust gases and particulates by means of an auxiliary heat source and the heat generated within the reaction chamber is stored in the individual heat exchange-filter elements during the discharge of exhaust gases therethrough from the reaction chamber and this heat is then transferred to the inflowing volume of the exhaust gases so that, in effect, exhaust gas is discharged from the device at substantially the same temperature as it was during its inlet into the device from the engine.

Packaging of radioactive sludges at the Saclay effluent processing plant

International Nuclear Information System (INIS)

Cerre, Pierre; Mestre, Emile; Bourdrez, Jean; Leconnetable, Jean

1964-10-01

The authors describe technical and technological aspects of the packaging workshop for radioactive sludges produced by processes of co-precipitation of Saclay effluents. This facility is an achievement of studies which aimed at improving working conditions for the plant staff. This workshop implements a process of solidification of filtered sludge by mixing with a hydraulic binding agent. After some generalities on the decontamination process applied to effluents produced by the Saclay research centre, the authors present and describe the adopted process, propose a physical description of the facility: building, chemical engineering equipment (filtration, packaging, and handling). They describe facility operation: introduction of a block into the cell, block filling, output of a packaged container. They briefly discuss the first results of facility exploitation [fr

Active slag filters-simple and sustainable phosphorus removal from wastewater using steel industry byproduct.

Science.gov (United States)

Pratt, C; Shilton, A

2010-01-01

Active filtration, where effluent is passed through a reactive substrate such as steel slag, offers a simple and cost-effective option for removing phosphorus (P) from effluent. This work summarises a series of studies that focused on the world's only full-scale active slag filter operated through to exhaustion. The filter achieved 75% P-removal during its first 5 years, reaching a retention capacity of 1.23 g P/kg slag but then its performance sharply declined. Scanning electron microscopy, X-ray diffraction, X-ray fluorescence, and chemical extractions revealed that P sequestration was primarily achieved via adsorption onto iron (Fe) oxyhydroxides on the slag's surface. It was concluded that batch equilibrium tests, whose use has been repeatedly proposed in the literature, cannot be used as an accurate predictor of filter adsorption capacity because Fe oxyhydroxides form via chemical weathering in the field, and laboratory tests don't account for this. Research into how chemical conditions affect slag's P retention capacity demonstrated that near-neutral pH and high redox are optimal for Fe oxyhydroxide stability and overall filter performance. However, as Fe oxyhydroxide sites fill up, removal capacity becomes exhausted. Attempts to regenerate P removal efficiency using physical techniques proved ineffective contrary to dogma in the literature. Based on the newly-developed understanding of the mechanisms of P removal, chemical regeneration techniques were investigated and were shown to strip large quantities of P from filter adsorption sites leading to a regenerated P removal efficiency. This raises the prospect of developing a breakthrough technology that can repeatedly remove and recover P from effluent.

Two stage treatment of dairy effluent using immobilized Chlorella pyrenoidosa

Science.gov (United States)

2013-01-01

Background Dairy effluents contains high organic load and unscrupulous discharge of these effluents into aquatic bodies is a matter of serious concern besides deteriorating their water quality. Whilst physico-chemical treatment is the common mode of treatment, immobilized microalgae can be potentially employed to treat high organic content which offer numerous benefits along with waste water treatment. Methods A novel low cost two stage treatment was employed for the complete treatment of dairy effluent. The first stage consists of treating the diary effluent in a photobioreactor (1 L) using immobilized Chlorella pyrenoidosa while the second stage involves a two column sand bed filtration technique. Results Whilst NH4+-N was completely removed, a 98% removal of PO43--P was achieved within 96 h of two stage purification processes. The filtrate was tested for toxicity and no mortality was observed in the zebra fish which was used as a model at the end of 96 h bioassay. Moreover, a significant decrease in biological oxygen demand and chemical oxygen demand was achieved by this novel method. Also the biomass separated was tested as a biofertilizer to the rice seeds and a 30% increase in terms of length of root and shoot was observed after the addition of biomass to the rice plants. Conclusions We conclude that the two stage treatment of dairy effluent is highly effective in removal of BOD and COD besides nutrients like nitrates and phosphates. The treatment also helps in discharging treated waste water safely into the receiving water bodies since it is non toxic for aquatic life. Further, the algal biomass separated after first stage of treatment was highly capable of increasing the growth of rice plants because of nitrogen fixation ability of the green alga and offers a great potential as a biofertilizer. PMID:24355316

Demasculinization of male fish by wastewater treatment plant effluent

Science.gov (United States)

Vajda, A.M.; Barber, L.B.; Gray, J.L.; Lopez, E.M.; Bolden, A.M.; Schoenfuss, H.L.; Norris, D.O.

2011-01-01

Adult male fathead minnows (Pimephales promelas) were exposed to effluent from the City of Boulder, Colorado wastewater treatment plant (WWTP) under controlled conditions in the field to determine if the effluent induced reproductive disruption in fish. Gonadal intersex and other evidence of reproductive disruption were previously identified in white suckers (Catostomus commersoni) in Boulder Creek downstream from this WWTP effluent outfall. Fish were exposed within a mobile flow-through exposure laboratory in July 2005 and August 2006 to WWTP effluent (EFF), Boulder Creek water (REF), or mixtures of EFF and REF for up to 28 days. Primary (sperm abundance) and secondary (nuptial tubercles and dorsal fat pads) sex characteristics were demasculinized within 14 days of exposure to 50% and 100% EFF. Vitellogenin was maximally elevated in both 50% and 100% EFF treatments within 7 days and significantly elevated by 25% EFF within 14 days. The steroidal estrogens 17??-estradiol, estrone, estriol, and 17??-ethynylestradiol, as well as estrogenic alkylphenols and bisphenol A were identified within the EFF treatments and not in the REF treatment. These results support the hypothesis that the reproductive disruption observed in this watershed is due to endocrine-active chemicals in the WWTP effluent. ?? 2011 Elsevier B.V.

Synergistic effect of ultrasonic pre-treatment combined with UV irradiation for secondary effluent disinfection.

Science.gov (United States)

Jin, Xin; Li, Zifu; Xie, Lanlan; Zhao, Yuan; Wang, Tingting

2013-11-01

The ultraviolet (UV) disinfection efficiency is often affected by suspended solids (SS). Given their high concentration or large particle size, SS can scatter UV light and provide shielding for bacteria. Thus, ultrasound is often employed as a pre-treatment process to improve UV disinfection. This work investigated the synergistic effect of ultrasound combined with UV for secondary effluent disinfection. Bench-scale experiments were conducted in using samples obtained from secondary sedimentation tanks. These tanks belonged to three wastewater treatment plants in Beijing that use different kinds of biological treatment methods. Several parameters may contribute to the changes in the efficiency of ultrasound and UV disinfection. Thus, the frequency and energy density of ultrasound, as well as the SS, were investigated. Results demonstrated that samples which have relatively higher SS concentrations or higher percentages of larger particles have less disinfection efficiency using UV disinfection alone. However, the presence of ultrasound could improve the disinfection efficiency because it has synergistic effect. Changes in the particle size distribution and SS concentration notably affected the efficiency of UV disinfection. The efficiency of Escherichia coli elimination can be decreased by 1.2 log units as the SS concentration increases from 16.9 mg/l to 25.4 mg/l at a UV energy density of 40 mJ/cm(2). UV disinfection alone reduced the E. coli population by 3.4 log units. However, the synergistic disinfection of ultrasound and UV could reach 5.4 log units during the reduction of E. coli at a 40 kHz frequency and an energy density of 2.64 kJ/l. The additional synergistic effect is 1.1 log units. Copyright © 2013 Elsevier B.V. All rights reserved.

Minimizing secondary coolant blowdown in HANARO

International Nuclear Information System (INIS)

Park, Y. C.; Woo, J. S.; Ryu, J. S.; Cho, Y. G.; Lim, N. Y.

2000-01-01

There is about 80m 3 /h loss of the secondary cooling water by evaporation, windage and blowdown during the operation of HANARO, 30MW research reactor. The evaporation and the windage is necessary loss to maintain the performance of cooling tower, but the blowdown is artificial lose to get rid of the foreign material and to maintain the quality of the secondary cooling water. Therefore, minimizing the blowdown loss was studied. It was confirmed, through the relation of the number of cycle and the loss rate of secondary coolant, that the number of cycle is saturated to 12 without blowdown because of the windage loss. When the secondary coolant is treated by high Ca-hardness treatment program (the number of cycle > 10) to maintain the number of cycle around 12 without blowdown, only the turbidity exceeds the limit. By adding filtering system it was confirmed, through the relation of turbidity and filtering rate of secondary cooling water, that the turbidity is reduced below the limit (5 deg.) by 2% of filtering rate without blowdown. And it was verified, through the performance test of back-flow filtering unit, that this unit gets rid of foreign material up to 95% of the back-flow and that the water can be reused as coolant. Therefore, the secondary cooling water can be treated by the high Ca-hardness program and filter system without blowdown

Integration of sand and membrane filtration systems for iron and pesticide removal without chemical addition

DEFF Research Database (Denmark)

Kowalski, Krysztof; Madsen, Henrik Tækker; Søgaard, Erik Gydesen

2013-01-01

the content of key foulants, the techniques can be used as a pre-treatment for nanofiltration and low pressure reverse osmosis that has proved to be capable of removing pesticides. It was found that a lower fouling potential could be obtained by using the membranes, but that sand filter was better at removing......Pilot plant investigations of sand and membrane filtration (MF/UF/NF/LPRO) have been performed to treat groundwater polluted with pesticides. The results show that simple treatment, with use of aeration and sand filtration or MF/UF membranes, does not remove pesticides. However, by reducing...... manganese and dissolved organic matter. The results indicate that combining aeration; sand filtration and membrane techniques might be a good option for pesticide removal without any addition of chemicals and minimized membrane maintenance....

In situ bioremediation of trichloroethylene-contaminated water by a resting-cell methanotrophic microbial filter

International Nuclear Information System (INIS)

Taylor, R.T.; Duba, A.G.; Durham, W.B.; Hanna, M.L.; Jackson, K.J.; Jovanovich, M.C.; Knapp, R.B.; Knezovich, J.P.; Shah, N.N.; Shonnard, D.R.; Wijesinghe, A.M.

1992-10-01

The Lawrence Livermore National Laboratory is testing and developing an in situ microbial filter technology for remediating migrating subsurface plumes contaminated with low concentrations of trichloroethylene (TCE). Their current focus is the establishment of a replenishable bioactive zone (catalytic filter) along expanding plume boundaries by the Injection of a representative methanotrophic bacterium, Methylosinus trichosporium OB3b. We have successfully demonstrated this microbial filter strategy using emplaced, attached resting cells (no methane additions) in a 1.1-m flow-through test bed loaded with water-saturated sand. Two separate 24 h pulses of TCE (109 ppb and 85 ppb), one week apart, were pumped through the system at a flow velocity of 1.5 cm/h; no TCE (<0.5 ppb) was detected on the downstream side of the microbial filter. Subsequent excavation of the wet sand confirmed the existence of a TCE-bioactive zone 19 days after it had been created. An enhanced longevity of the cellular, soluble-form methane monooxygenase produced by this methanotroph Is a result of our laboratory bioreactor culturing conditions. Additional experiments with cells in sealed vials and emplaced in the 1.1-m test bed yielded a high resting-cell finite TCE biotransformation capacity of ∼ 0.25 mg per mg of bacteria; this is suitable for a planned sand-filled trench field demonstration at a Lawrence Livermore National Laboratory site

Performance Comparison of Various Filters Media in

Directory of Open Access Journals (Sweden)

Lilyan Yaqup Matti

2013-05-01

Full Text Available   In this research, a bench-scale filter is designed and constructed in order to compare the performance of different media namely, sand, crushed marble stone and crushed red brick. The filters are operated under various operating conditions such as filter depth, raw water turbidity, pretreatment, effective size and uniformity coefficient.          These filters are operated under conventional and direct filtration modes with different doses of alum. Statistical methods had been used to determine the best media using  Duncan multiple range test.     The result showed the superiority of crushed red brick media in the  removal of turbidity and total bacteria. The results also indicated that filters operated under direct filtration mode show better performance than that operated under conventional filtration mode. The pH of treated water show slight increase for the two modes of filtration.

The Use of Aquatic Macrophyte Ecotoxicological Assays in Monitoring Coastal Effluent Discharges in Southern Australia

Energy Technology Data Exchange (ETDEWEB)

Burridge, T.R.; Karistianos, M.; Bidwell, J

1999-01-01

Germination inhibition of zoospores of the aquatic, brown algal macrophyte Ecklonia radiata was employed to assess the toxicity of sewage effluents under short to long term exposure and under modified salinity conditions. The rate of germination inhibition was determined for exposure times between 2 and 48 h in salinity modified and unmodified regimes and under reduced salinity conditions alone. The results indicated that rate of germination inhibition increased with duration of exposure to sewage effluents and to salinity reduction alone, and that response to the effluents may be enhanced under conditions of reduced salinity. Whilst the effect of primary treated effluent was primarily that of toxicity, secondary treated effluent effects appeared to be primarily that of reduced salinity although at a greater rate than would be expected for salinity reduction alone. The assay is suggested to provide a mechanism for monitoring sewage effluent quality and to monitor potential impacts of sewage effluent discharge on kelp communities in southern Australia.

The Use of Aquatic Macrophyte Ecotoxicological Assays in Monitoring Coastal Effluent Discharges in Southern Australia

International Nuclear Information System (INIS)

Burridge, T.R.; Karistianos, M.; Bidwell, J.

1999-01-01

Germination inhibition of zoospores of the aquatic, brown algal macrophyte Ecklonia radiata was employed to assess the toxicity of sewage effluents under short to long term exposure and under modified salinity conditions. The rate of germination inhibition was determined for exposure times between 2 and 48 h in salinity modified and unmodified regimes and under reduced salinity conditions alone. The results indicated that rate of germination inhibition increased with duration of exposure to sewage effluents and to salinity reduction alone, and that response to the effluents may be enhanced under conditions of reduced salinity. Whilst the effect of primary treated effluent was primarily that of toxicity, secondary treated effluent effects appeared to be primarily that of reduced salinity although at a greater rate than would be expected for salinity reduction alone. The assay is suggested to provide a mechanism for monitoring sewage effluent quality and to monitor potential impacts of sewage effluent discharge on kelp communities in southern Australia

Y-chromosomal DNA markers for discrimination of chemical substance and effluent effects on sexual differentiation in salmon.

OpenAIRE

Afonso, Luis O B; Smith, Jack L; Ikonomou, Michael G; Devlin, Robert H

2002-01-01

Chinook salmon alevins were exposed during their labile period for sex differentiation to different concentrations of bleached kraft mill effluent (BKME), primary sewage effluent, secondary sewage effluent (SE), 17ss-estradiol, testosterone, and nonylphenol. After exposure for 29 days post hatching (DPH), fish were allowed to grow until 103 and 179 DPH, at which time their genetic sex was determined using Y-chromosomal DNA markers and their gonadal sex was determined by histology. Independent...

40 CFR 421.200 - Applicability: Description of the secondary mercury subcategory.

Science.gov (United States)

2010-07-01

... secondary mercury subcategory. 421.200 Section 421.200 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY Secondary Mercury Subcategory § 421.200 Applicability: Description of the secondary mercury...

Control of biological growth in recirculating cooling systems using treated secondary effluent as makeup water with monochloramine.

Science.gov (United States)

Chien, Shih-Hsiang; Chowdhury, Indranil; Hsieh, Ming-Kai; Li, Heng; Dzombak, David A; Vidic, Radisav D

2012-12-01

was used as compared to in-situ-formed monochloramine. Adjustment of biocide dose to maintain monochloramine residual above 3mg/L is needed to achieve successful biological growth control in recirculating cooling systems using secondary-treated municipal effluent as the only source of makeup water. Copyright © 2012 Elsevier Ltd. All rights reserved.

Contribuição da estrutura interna na perda de carga de filtros de areia utilizados na irrigação Contribution of the internal structure in the sand filters head loss used in irrigation

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Marcio Mesquita

2012-02-01

Full Text Available A dinâmica de operação dos filtros de areia afeta o desempenho hidráulico do sistema de irrigação, elevando a perda de carga e alterando a altura manométrica total do sistema. Buscando entender parte dessa dinâmica, o objetivo deste trabalho foi determinar o efeito da estrutura interna de filtros de areia na perda de carga de três modelos de equipamentos fabricados no Brasil, sem a presença do elemento filtrante e utilizando água limpa. Adicionalmente, com o ajuste do modelo matemático exponencial aos dados experimentais, procurou-se estabelecer comparações entre os tipos de estrutura dos filtros avaliados. Os ensaios foram realizados em um módulo experimental construído no Laboratório de Hidráulica e Irrigação da FEAGRI/UNICAMP. Os resultados mostraram que a estrutura hidráulica interna dos filtros determinou comportamentos hidráulicos diferenciados e que os tipos de estruturas (placa difusora e drenos alteraram o padrão de operação dos modelos ensaiados. A função matemática proposta representou, significativamente, o fenômeno físico de perda de carga para as condições do experimento.The dynamic of operation of sand filters affect the hydraulic performance of irrigation systems, increasing the head loss and changing the total dynamic head of the system. Trying to understand part of this dynamic, the objective of this research was to determine the effect of internal hydraulic structures in the head loss of three sand filters of commercial models, manufactured in Brazil and operating without the filter layer and with clean water. In addition, using an exponential mathematical model adjusted to the experimental data, comparisons among types of structure of each evaluated filter were performed. The trails were accomplished in the experimental module developed in the Laboratory of Hydraulics and Irrigation of FEAGRI / UNICAMP. The results showed that the filters structures determined differentiate hydraulic behaviors

Environmental Impacts of Sand Exploitation. Analysis of Sand Market

Directory of Open Access Journals (Sweden)

Marius Dan Gavriletea

2017-06-01

Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

Effluent and gamma-irradiated digested sludge additions on calcareous soils

International Nuclear Information System (INIS)

Lee-Rodriguez, V.

1978-01-01

The long-term use of sewage effluent and the use of gamma-irradiated treated digested sewage sludge (RDSS) were studied under field and greenhouse conditions, respectively. The purpose of this investigation was to: (1) study the effect of long and short-term application of secondary sewage effluent and RDSS, respectively, on the buildup of iron and phytotoxicity problems on calcareous soils; (2) study the potential phytotoxicity of RDSS and observe the micronutrient fertilizer value of RDSS through three successive plantings on calcareous soil; (3) evaluate RDSS as a source of iron in a soil known to be severely iron-deficient

Peat wetland as a natural filter of effluents from adjacent industrial areas

OpenAIRE

József DEZSO; Gabriella TÓTH; Dénes LÓCZY

2015-01-01

The main objective of the project is the study of a peat wetland functioning as recipient of effluents from former and present-day industrial activities. The investigation was focused on heavy metal contaminations and their probable mobilization or fixation. The studied peatbog is a typical Eastern European wetland, located in Hungary on the border between medium mountains (Bakony Mountains) and a Neogene basin (the Sárrét, an area under nature conservation). Watercourses and prevailing air c...

Scope for utilizing gamma radiation for microbiological control of sewage waste-water in India

International Nuclear Information System (INIS)

Lewis, N.F.

1975-01-01

Conventional methods, including the activated sludge process, the trickling filter process and oxidation pond process, of treating sewage waste in India, do not adequately ensure safe utilization of the secondary effluent for land irrigation purposes. Preliminary findings indicate that gamma radiation in the range of 0.1-0.3 Mrad effectively destroys pathogens in the secondary effluent, thereby making available very large quantities of water for land irrigation and industrial purposes. (author)

THE ROLE OF DUCKWEED (LEMNA MINOR L. IN SECONDARY CLARIFIER TANKS

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Engin Gürtekin

2008-01-01

Full Text Available In this study, the effects of duckweed (Lemna minor L. presence on the effluent water quality and settling characteristics in the secondary clarifier tank of a conventional biological treatment plant were investigated. For this purpose, the performances of the secondary clarifier with and without duckweed were compared. In the secondary clarifier tank with duckweed, COD, BOD5, ammonium and phosphate removal efficiencies were higher by 15, 25, 35 and 45%, respectively. SS concentration of effluent and values of sludge volume index (SVI were the same. The results showed that duckweed contributes to treatment efficiency of conventional biological treatment plant, which reduces the need of tertiary nutrients removal.

Impact of pulp and paper mill effluents and solid wastes on soil mineralogical and physicochemical properties.

Science.gov (United States)

Adhikari, Gopi; Bhattacharyya, Krishna G

2015-03-01

The present study was carried out to evaluate the impact of the effluents and the solid wastes generated by a giant pulp and paper mill in the northeastern part of India on soil mineralogy of the area. The impacts were monitored by analysis of soil samples from seven sites located in the potential impact zone and a control site where any kind of effluent discharge or solid waste dumping was absent. The soil belonged to medium texture type (sandy clay loam, sandy loam, loamy sand, and silt loam), and the soil aggregate analysis indicated higher levels of organic carbon, pH, electrical conductivity, effective cation exchange capacity, and mean weight diameter at sites receiving effluents and solid wastes from the pulp and paper mill. Depletion in soil silica level and in feldspar and quartz contents and rise in iron and calcium contents at the sites receiving effluents from the pulp and paper mill indicated significant influence on soil mineralogy. The soil contained a mixture of minerals consisting of tectosilicates (with silicate frameworks as in quartz or feldspar), phylosilicates (layered clays like kaolinite, smectite, chlorite, illite, etc.), and carbonates. Absence of pure clay minerals indicated a state of heterogeneous intermediate soil clay transformation. The significance of the mixed mineralogy in relation to the disposal of effluents and dumping of solid wastes is discussed in details.

Recycled sand in lime-based mortars.

Science.gov (United States)

Stefanidou, M; Anastasiou, E; Georgiadis Filikas, K

2014-12-01

The increasing awareness of the society about safe guarding heritage buildings and at the same time protecting the environment promotes strategies of combining principles of restoration with environmentally friendly materials and techniques. Along these lines, an experimental program was carried out in order to investigate the possibility of producing repair, lime-based mortars used in historic buildings incorporating secondary materials. The alternative material tested was recycled fine aggregates originating from mixed construction and demolition waste. Extensive tests on the raw materials have been performed and mortar mixtures were produced using different binding systems with natural, standard and recycled sand in order to compare their mechanical, physical and microstructure properties. The study reveals the improved behavior of lime mortars, even at early ages, due to the reaction of lime with the Al and Si constituents of the fine recycled sand. The role of the recycled sand was more beneficial in lime mortars rather than the lime-pozzolan or lime-pozzolan-cement mortars as a decrease in their performance was recorded in the latter cases due to the mortars' structure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluation of Plastic Household Biosand Filter (BSF) In Combination with Solar Disinfection (SODIS) For Water Treatment

International Nuclear Information System (INIS)

Hussain, G.; Haydar, S.; Bari, A. J.; Anis, M.; Asif, Z.; Aziz, J. A.

2015-01-01

Efficiency of a household plastic biosand filter (BSF) for the removal of turbidity and fecal contamination was evaluated. Water of river Ravi was used as influent. Water filtered through BSF was further treated using Solar Disinfection (SODIS). The study was conducted for raw water with low pollution level (total coliforms <500 MPN/100 ml) and high pollution level (total coliforms between 500-20,000 MPN/100 ml). The average value of turbidity removal by BSF was 94.5 percentage with 0.9 NTU as average turbidity of effluent. For raw water with low pollution level, the BSF was able to achieve a maximum of 2.2 log10 unit reduction (99.4 percentage) for total coliforms (39 MPN/100 mL in effluent) and 1.95 log10 unit reduction (98.5 percentage) for fecal coliforms (9 MPN/100 mL in effluent). While for raw water with high pollution level, the maximum removal of 1.5 log10 unit (97.5 percentage) for total coliforms (1430 MPN/100 mL in effluent) and 1.8 log10 units (98.4 percentage) for fecal coliforms (387 MPN/100 mL in effluent) was achieved in BSF. To make the effluent fit for drinking it was further treated using SODIS, which rendered the BSF effluent fit for drinking with zero fecal coliforms count (for full sunny and partially cloudy conditions). Newly proposed plastic BSF could be a good replacement of already used concrete household BSF (used in more than 63 countries) being cheaper in cost and lighter in weight by 85 percentage and 80 percentage, respectively than the concrete BSF. (author)

Sources of particulate matter components in the Athabasca oil sands region: investigation through a comparison of trace element measurement methodologies

Science.gov (United States)

Phillips-Smith, Catherine; Jeong, Cheol-Heon; Healy, Robert M.; Dabek-Zlotorzynska, Ewa; Celo, Valbona; Brook, Jeffrey R.; Evans, Greg

2017-08-01

The province of Alberta, Canada, is home to three oil sands regions which, combined, contain the third largest deposit of oil in the world. Of these, the Athabasca oil sands region is the largest. As part of Environment and Climate Change Canada's program in support of the Joint Canada-Alberta Implementation Plan for Oil Sands Monitoring program, concentrations of trace elements in PM2. 5 (particulate matter smaller than 2.5 µm in diameter) were measured through two campaigns that involved different methodologies: a long-term filter campaign and a short-term intensive campaign. In the long-term campaign, 24 h filter samples were collected once every 6 days over a 2-year period (December 2010-November 2012) at three air monitoring stations in the regional municipality of Wood Buffalo. For the intensive campaign (August 2013), hourly measurements were made with an online instrument at one air monitoring station; daily filter samples were also collected. The hourly and 24 h filter data were analyzed individually using positive matrix factorization. Seven emission sources of PM2. 5 trace elements were thereby identified: two types of upgrader emissions, soil, haul road dust, biomass burning, and two sources of mixed origin. The upgrader emissions, soil, and haul road dust sources were identified through both the methodologies and both methodologies identified a mixed source, but these exhibited more differences than similarities. The second upgrader emissions and biomass burning sources were only resolved by the hourly and filter methodologies, respectively. The similarity of the receptor modeling results from the two methodologies provided reassurance as to the identity of the sources. Overall, much of the PM2. 5-related trace elements were found to be anthropogenic, or at least to be aerosolized through anthropogenic activities. These emissions may in part explain the previously reported higher levels of trace elements in snow, water, and biota samples collected

Sources of particulate matter components in the Athabasca oil sands region: investigation through a comparison of trace element measurement methodologies

Directory of Open Access Journals (Sweden)

C. Phillips-Smith

2017-08-01

Full Text Available The province of Alberta, Canada, is home to three oil sands regions which, combined, contain the third largest deposit of oil in the world. Of these, the Athabasca oil sands region is the largest. As part of Environment and Climate Change Canada's program in support of the Joint Canada-Alberta Implementation Plan for Oil Sands Monitoring program, concentrations of trace elements in PM2. 5 (particulate matter smaller than 2.5 µm in diameter were measured through two campaigns that involved different methodologies: a long-term filter campaign and a short-term intensive campaign. In the long-term campaign, 24 h filter samples were collected once every 6 days over a 2-year period (December 2010–November 2012 at three air monitoring stations in the regional municipality of Wood Buffalo. For the intensive campaign (August 2013, hourly measurements were made with an online instrument at one air monitoring station; daily filter samples were also collected. The hourly and 24 h filter data were analyzed individually using positive matrix factorization. Seven emission sources of PM2. 5 trace elements were thereby identified: two types of upgrader emissions, soil, haul road dust, biomass burning, and two sources of mixed origin. The upgrader emissions, soil, and haul road dust sources were identified through both the methodologies and both methodologies identified a mixed source, but these exhibited more differences than similarities. The second upgrader emissions and biomass burning sources were only resolved by the hourly and filter methodologies, respectively. The similarity of the receptor modeling results from the two methodologies provided reassurance as to the identity of the sources. Overall, much of the PM2. 5-related trace elements were found to be anthropogenic, or at least to be aerosolized through anthropogenic activities. These emissions may in part explain the previously reported higher levels of trace elements in snow

Filter apparatus for actively reducing noise

NARCIS (Netherlands)

Berkhoff, Arthur P.; Nijsse, G.

2010-01-01

A filter apparatus for reducing noise from a primary noise source, comprising a secondary source signal connector for generating secondary noise to reduce said primary noise and a sensor connector for connecting to a sensor for measuring said primary and secondary noise as an error signal. A first

Micropollutant degradation, bacterial inactivation and regrowth risk in wastewater effluents: Influence of the secondary (pre)treatment on the efficiency of Advanced Oxidation Processes.

Science.gov (United States)

Giannakis, Stefanos; Voumard, Margaux; Grandjean, Dominique; Magnet, Anoys; De Alencastro, Luiz Felippe; Pulgarin, César

2016-10-01

In this work, disinfection by 5 Advanced Oxidation Processes was preceded by 3 different secondary treatment systems present in the wastewater treatment plant of Vidy, Lausanne (Switzerland). 5 AOPs after two biological treatment methods (conventional activated sludge and moving bed bioreactor) and a physiochemical process (coagulation-flocculation) were tested in laboratory scale. The dependence among AOPs efficiency and secondary (pre)treatment was estimated by following the bacterial concentration i) before secondary treatment, ii) after the different secondary treatment methods and iii) after the various AOPs. Disinfection and post-treatment bacterial regrowth were the evaluation indicators. The order of efficiency was Moving Bed Bioreactor > Activated Sludge > Coagulation-Flocculation > Primary Treatment. As far as the different AOPs are concerned, the disinfection kinetics were: UVC/H2O2 > UVC and solar photo-Fenton > Fenton or solar light. The contextualization and parallel study of microorganisms with the micropollutants of the effluents revealed that higher exposure times were necessary for complete degradation compared to microorganisms for the UV-based processes and inversed for the Fenton-related ones. Nevertheless, in the Fenton-related systems, the nominal 80% removal of micropollutants deriving from the Swiss legislation, often took place before the elimination of bacterial regrowth risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Performance evaluation of a dual-flow recharge filter for improving groundwater quality.

Science.gov (United States)

Samuel, Manoj P; Senthilvel, S; Mathew, Abraham C

2014-07-01

A dual-flow multimedia stormwater filter integrated with a groundwater recharge system was developed and tested for hydraulic efficiency and pollutant removal efficiency. The influent stormwater first flows horizontally through the circular layers of planted grass and biofibers. Subsequently, the flow direction changes to a vertical direction so that water moves through layers of pebbles and sand and finally gets recharged to the deep aquifers. The media in the sequence of vegetative medium:biofiber to pebble:sand were filled in nine proportions and tested for the best performing combination. Three grass species, viz., Typha (Typha angustifolia), Vetiver (Chrysopogon zizanioides), and St. Augustine grass (Stenotaphrum secundatum), were tested as the best performing vegetative medium. The adsorption behavior of Coconut (Cocos nucifera) fiber, which was filled in the middle layer, was determined by a series of column and batch studies.The dual-flow filter showed an increasing trend in hydraulic efficiency with an increase in flowrate. The chemical removal efficiency of the recharge dual-flow filter was found to be very high in case of K+ (81.6%) and Na+ (77.55%). The pH normalizing efficiency and electrical conductivity reduction efficiency were also recorded as high. The average removal percentage of Ca2+ was moderate, while that of Mg2+ was very low. The filter proportions of 1:1 to 1:2 (plant:fiber to pebble:sand) showed a superior performance compared to all other proportions. Based on the estimated annual costs and returns, all the financial viability criteria (internal rate of return, net present value, and benefit-cost ratio) were found to be favorable and affordable to farmers in terms of investing in the developed filtration system.

The effectiveness of the use of filter on the tilapia growth performance, number of Nitrosomonas sp., and water quality in aquaponics systems

OpenAIRE

Yuli Andriani; , Zahidah; Yayat Dhahiyat; Ujang Subhan; Irfan Zidni; Rusky Intan Pratama; Nadia Purnamasari Gumay

2018-01-01

ABSTRACT This study aims to determine the most effective type of living filter media for the bacteria Nitrosomonas sp. in order to improve water quality in aquaponics systems. The method used in this study was completely randomized design, consisting of five treatments and each was repeated three times. The treatments were: A (without addition of filter media), B (addition of palm fibers, silica sand, and activated carbon), C (addition of palm fibers, silica sand, gravel, and activated carbon...

Effluent management and pollution control

International Nuclear Information System (INIS)

Ananda Narayanan, R.; Vedamoorthy, S.

2006-01-01

Generation of waste/effluent has a direct impact on environment, the higher the generation of waste higher the environmental impact. Though complete prevention of radioactive waste generation is a difficult task, keeping the waste generation to the minimum practicable is essential objective of Radioactive Waste Management. In doing so, it is essential to minimize waste generation at all the stages of a Nuclear Plant Cycle. Waste minimization refers to both a) Waste generation by operational and maintenance activities of plant and b) Secondary waste resulting from predisposal management of Radioactive Waste. The management of the effluent can be done in efficient manner by better designs, improved procedure, periodic reviews and above all inculcate the awareness amongst the waste generators since minimisation of waste, at source is the most efficient way to safe guard the environment. Commissioning and rich operating experience of waste management plant gather novel ideas which result in beneficial improvements in the system and operating procedure. Some of the steps initiated by designers and site agencies towards this are worth mentioning. (author)

Amélioration de la qualité microbiologique des effluents secondaires par stockage en bassins

Directory of Open Access Journals (Sweden)

Trad-Rais M.

1999-01-01

Full Text Available Microbiological quality improvement of secondary effluent by reservoir storage. Storing secondary effluents is of particular interest for water resource management. It constitutes further treatment which reduces the microbial contamination of water to a level where it can be used for the irrigation of all crops, without restriction. The storage of treated wastewater takes place during the winter, ensuring that such a resource is not lost and enabling a larger area to be irrigated during the dry season, thereby increasing agricultural production. Storage trials in reservoirs were conducted in north-eastern Tunisia. Their objective was to determine the length and conditions of secondary effluent decontamination as well as the impact of seasonal storage on water quality. The results indicate that the decontamination of effluents slows down with increased reservoir depth. For a depth of less than 150 cm, a reduction of fecal coliforms in the order of 3 log units is attained in 3 days when the average temperature of the water ranges from 22 to 25 degrees C; when this temperature is between 25.5 and 28 degrees C, the same reduction takes 8 days. Below 20 degrees C, decontamination is considerably reduced: for a mean water temperature ranging from 12.5 to 18 degrees C, the reduction of fecal coliforms reaches 3 log units only after a retention time of 17 days in the reservoir. Seasonal storage from 2 to 7 months does not affect the bacteriological quality of water: after decontamination, no proliferation of bacterial indicators occurs during storage.

A new depositional model for sand-rich loess on the Buckley Flats outwash plain, northwestern Lower Michigan

Science.gov (United States)

Nyland, Kelsey E.; Schaetzl, Randall J.; Ignatov, Anthony; Miller, Bradley A.

2018-04-01

Loess was first studied in Michigan on the Buckley Flats, where outwash, overlain by ≈70 cm of loamy sediment, was originally interpreted as loess mixed with underlying sands. This paper re-evaluates this landscape through a spatial analysis of data from auger samples and soil pits. To better estimate the loamy sediment's initial textures, we utilized "filtered" laser diffraction data, which remove much of the coarser sand data. Textures of filtered silt data for the loamy sediment are similar to loess. The siltiest soils are found in the low-relief, central part of the Flats. Spatial analyses revealed that many silt fractions are nearly uniformly distributed, suggesting that the loess was not derived from a single source. The previous depositional model for the loamy mantle relied on loessfall followed by pedoturbation, but does not explain (1) the variation in sand contents across the Flats, or (2) the abrupt contact below the loamy mantle. This contact suggests that the outwash was frozen when the sediments above were deposited. Deep gullies at the western margins of the Flats were likely cut as permafrost facilitated runoff. Our new model for the origin of the loamy mantle suggests that the sands on the uplands were generated from eroding gullies and saltated onto the uplands along with loess that fell more widely. Sands saltating to the west of the Flats may have entrained some silts, facilitating loessfall downwind. At most sites, the loamy mantle gets increasingly silty near the surface, suggesting that saltation ended before loess deposition.

Hydraulic fracture considerations in oil sand overburden dams

Energy Technology Data Exchange (ETDEWEB)

Cameron, R.; Madden, B.; Danku, M. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

2008-07-01

This paper discussed hydraulic fracture potential in the dry-filled temporary dams used in the oil sands industry. Hydraulic fractures can occur when reservoir fluid pressures are greater than the minimum stresses in a dam. Stress and strain conditions are influenced by pore pressures, levels of compaction in adjacent fills as well as by underlying pit floor and abutment conditions. Propagation pressure and crack initiation pressures must also be considered in order to provide improved hydraulic fracture protection to dams. Hydraulic fractures typically result in piping failures. Three cases of hydraulic fracture at oil sands operations in Alberta were presented. The study showed that hydraulic fracture failure modes must be considered in dam designs, particularly when thin compacted lift of dry fill are used to replace wetted clay cores. The risk of hydraulic fractures can be reduced by eliminating in situ bedrock irregularities and abutments. Overpressure heights, abutment sloping, and the sloping of fills above abutments, as well as the dam's width and base conditions must also be considered in relation to potential hydraulic fractures. It was concluded that upstream sand beaches and internal filters can help to prevent hydraulic fractures in dams in compacted control zones. 5 refs., 16 figs.

Sand transportation and reverse patterns over leeward face of sand dune

Science.gov (United States)

Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

2017-04-01

Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

A qualitative assessment of desertification change in the Tarfaya basin (Morocco using panchromatic data of Landsat ETM+ and oli: sand encroachment approach

Directory of Open Access Journals (Sweden)

Aydda Ali

2017-01-01

Full Text Available The purpose of the present work is to assess desertification change in the Tarfaya basin (Morocco based on quantifying sand dunes mass change at the corridor scale using two Panchromatic bands of Landsat ETM+ and OLI with 15 m of resolution covering the study area for ten years (2005–2016. In this work, the sand dunes quantification is qualitative and is based on automatic extraction and classification of sand dunes shape using co-occurence texture filters and Support Vector Machine (SVM classifier. The statistical results show that the area covered by sand was increased during the last ten years, which reveal that desertification becomes more intense.

Tertiary treatment of textile wastewater with combined media biological aerated filter (CMBAF) at different hydraulic loadings and dissolved oxygen concentrations

International Nuclear Information System (INIS)

Liu Fang; Zhao Chaocheng; Zhao Dongfeng; Liu Guohua

2008-01-01

An up-flow biological aerated filter packed with two layers media was employed for tertiary treatment of textile wastewater secondary effluent. Under steady state conditions, good performance of the reactor was achieved and the average COD, NH 4 + -N and total nitrogen (TN) in the effluent were 31, 2 and 8 mg/L, respectively. For a fixed dissolved oxygen (DO) concentration, an increase of hydraulic loading resulted in a decrease in substrate removal. With the increase of hydraulic loadings from 0.13 to 0.78 m 3 /(m 2 h), the removal efficiencies of COD, NH 4 + -N and TN all decreased, which dropped from 52 to 38%, from 90 to 68% and from 45 to 33%, respectively. In addition, the results also confirmed that the increase of COD and NH 4 + -N removal efficiencies resulted from the increase of DO concentrations, but this variation trend was not observed for TN removal. With the increase of DO concentrations from 2.4 to 6.1 mg/L, the removal efficiencies of COD and NH 4 + -N were 39-53% and 64-88%, whenas TN removal efficiencies increased from 39 to 42% and then dropped to 35%

Effective removal of trace thallium from surface water by nanosized manganese dioxide enhanced quartz sand filtration.

Science.gov (United States)

Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Zhou, Jian; Jiang, Jin; Wang, Yaan

2017-12-01

Thallium (Tl) has drawn wide concern due to its high toxicity even at extremely low concentrations, as well as its tendency for significant accumulation in the human body and other organisms. The need to develop effective strategies for trace Tl removal from drinking water is urgent. In this study, the removal of trace Tl (0.5 μg L -1 ) by conventional quartz sand filtration enhanced by nanosized manganese dioxide (nMnO 2 ) has been investigated using typical surface water obtained from northeast China. The results indicate that nMnO 2 enhanced quartz sand filtration could remove trace Tl(I) and Tl(III) efficiently through the adsorption of Tl onto nMnO 2 added to a water matrix and onto nMnO 2 attached on quartz sand surfaces. Tl(III)-HA complexes might be responsible for higher residual Tl(III) in the effluent compared to residual Tl(I). Competitive Ca 2+ cations inhibit Tl removal to a certain extent because the Ca 2+ ions will occupy the Tl adsorption site on nMnO 2 . Moreover, high concentrations of HA (10 mgTOC L -1 ), which notably complexes with and dissolves nMnO 2 (more than 78%), resulted in higher residual Tl(I) and Tl(III). Tl(III)-HA complexes might also enhance Tl(III) penetration to a certain extent. Additionally, a higher pH level could enhance the removal of trace Tl from surface water. Finally, a slight increase of residual Tl was observed after backwash, followed by the reduction of the Tl concentration in the effluent to a "steady" state again. The knowledge obtained here may provide a potential strategy for drinking water treatment plants threatened by trace Tl. Copyright © 2017. Published by Elsevier Ltd.

Effluent standards

Energy Technology Data Exchange (ETDEWEB)

Geisler, G C [Pennsylvania State University (United States)

1974-07-01

At the conference there was a considerable interest in research reactor standards and effluent standards in particular. On the program, this is demonstrated by the panel discussion on effluents, the paper on argon 41 measured by Sims, and the summary paper by Ringle, et al. on the activities of ANS research reactor standards committee (ANS-15). As a result, a meeting was organized to discuss the proposed ANS standard on research reactor effluents (15.9). This was held on Tuesday evening, was attended by members of the ANS-15 committee who were present at the conference, participants in the panel discussion on the subject, and others interested. Out of this meeting came a number of excellent suggestions for changes which will increase the utility of the standard, and a strong recommendation that the effluent standard (15.9) be combined with the effluent monitoring standard. It is expected that these suggestions and recommendations will be incorporated and a revised draft issued for comment early this summer. (author)

A filter apparatus for actively reducing noise

NARCIS (Netherlands)

Berkhoff, Arthur P.; Nijsse, G.

2006-01-01

A filter apparatus for reducing noise from a primary noise source, comprising a secondary source signal connector for generating secondary noise to reduce said primary noise and a sensor connector for connecting to a sensor for measuring said primary and secondary noise as an error signal. A first

Assessment of peracetic acid disinfected effluents by microbiotests.

Science.gov (United States)

Antonelli, M; Mezzanotte, V; Panouillères, M

2009-09-01

Bioassays were performed by commercially available kits on peracetic acid (PAA) solutions, at different concentrations, and on secondary effluents (from two different wastewater treatment plants) after disinfection at bench-scale, considering both samples containing residual active PAA and the same samples where residual PAA was quenched. Four indicator organisms were used: Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, and Selenastrum capricornutum. The experiments lead to conclude that Thamnocephalus platyurus is a very sensitive organism, probably not adequate to perform a reliable toxicity assessment of effluents for monitoring purposes. The presence of specific organic compounds deriving from human metabolism and urban pollution, even at very low concentrations, can affect the results of bioassays, especially those performed on Vibrio fischeri. PAA is toxic for bacteria and crustaceans even at concentrations lower than the ones commonly used in wastewater disinfection (2-5 mg/L), while its effect on algae is smaller. The toxic effect on bacteria was expected, as PAA is used for disinfection, but its possible influence on biological processes in the receiving aquatic environment should be considered. Toxicity on crustaceans would confirm the fact that discharging disinfected effluents could raise some environmental problems.

Occurrence of pharmaceutical compounds in urban wastewater: Removal, mass load and environmental risk after a secondary treatment—A review

International Nuclear Information System (INIS)

Verlicchi, P.; Al Aukidy, M.; Zambello, E.

2012-01-01

This review focuses on 118 pharmaceuticals, belonging to seventeen different therapeutic classes, detected in raw urban wastewater and effluent from an activated sludge system, a usual treatment adopted for urban wastewaters worldwide prior to final discharge into surface water bodies. Data pertaining to 244 conventional activated sludge systems and 20 membrane biological reactors are analysed and the observed ranges of variability of each selected compound in their influent and effluent reported, with particular reference to the substances detected most frequently and in higher concentrations. A snapshot of the ability of these systems to remove such compounds is provided by comparing their global removal efficiencies for each substance. Where possible, the study then evaluates the average daily mass load of the majority of detected pharmaceuticals exiting the secondary treatment step. The final part of the review provides an assessment of the environmental risk posed by their presence in the secondary effluent by means of the risk quotient that is the ratio between the average pharmaceutical concentration measured in the secondary effluent and the predicted no-effect concentration. Finally, mass load rankings of the compounds under review are compared with those based on their risk level. This analysis shows that the highest amounts discharged through secondary effluent pertain to one antihypertensive, and several beta-blockers and analgesics/anti-inflammatories, while the highest risk is posed by antibiotics and several psychiatric drugs and analgesics/anti-inflammatories. These results are reported with a view to aiding scientists and administrators in planning measures aiming to reduce the impact of treated urban wastewater discharge into surface water bodies. - Highlights: ► The review refers to 118 pharmaceuticals occurring in raw and treated wastewaters. ► Data from 264 municipal WWTPs with a CAS or an MBR were analysed. ► The removal rates achieved

Occurrence of pharmaceutical compounds in urban wastewater: Removal, mass load and environmental risk after a secondary treatment-A review

Energy Technology Data Exchange (ETDEWEB)

Verlicchi, P., E-mail: paola.verlicchi@unife.it [Dept. of Engineering, University of Ferrara, Via Saragat 1, I-44122 Ferrara (Italy); Terra and AcquaTech Technopoles, Via Borsari 46, I-44121 Ferrara (Italy); Al Aukidy, M., E-mail: mustafakether.alaukidi@unife.it [Dept. of Engineering, University of Ferrara, Via Saragat 1, I-44122 Ferrara (Italy); Zambello, E., E-mail: elena.zambello@unife.it [Dept. of Engineering, University of Ferrara, Via Saragat 1, I-44122 Ferrara (Italy); Terra and AcquaTech Technopoles, Via Borsari 46, I-44121 Ferrara (Italy)

2012-07-01

This review focuses on 118 pharmaceuticals, belonging to seventeen different therapeutic classes, detected in raw urban wastewater and effluent from an activated sludge system, a usual treatment adopted for urban wastewaters worldwide prior to final discharge into surface water bodies. Data pertaining to 244 conventional activated sludge systems and 20 membrane biological reactors are analysed and the observed ranges of variability of each selected compound in their influent and effluent reported, with particular reference to the substances detected most frequently and in higher concentrations. A snapshot of the ability of these systems to remove such compounds is provided by comparing their global removal efficiencies for each substance. Where possible, the study then evaluates the average daily mass load of the majority of detected pharmaceuticals exiting the secondary treatment step. The final part of the review provides an assessment of the environmental risk posed by their presence in the secondary effluent by means of the risk quotient that is the ratio between the average pharmaceutical concentration measured in the secondary effluent and the predicted no-effect concentration. Finally, mass load rankings of the compounds under review are compared with those based on their risk level. This analysis shows that the highest amounts discharged through secondary effluent pertain to one antihypertensive, and several beta-blockers and analgesics/anti-inflammatories, while the highest risk is posed by antibiotics and several psychiatric drugs and analgesics/anti-inflammatories. These results are reported with a view to aiding scientists and administrators in planning measures aiming to reduce the impact of treated urban wastewater discharge into surface water bodies. - Highlights: Black-Right-Pointing-Pointer The review refers to 118 pharmaceuticals occurring in raw and treated wastewaters. Black-Right-Pointing-Pointer Data from 264 municipal WWTPs with a CAS or an

Iodine filters in nuclear installations

International Nuclear Information System (INIS)

Wilhelm, J.G.

1982-01-01

The present report discusses the significance for environmental exposure of the iodine released with the gaseous effluents of nuclear power stations and reprocessing plants in relation to releases of other airborne radionuclides. Iodine filtration processes are described. The release pathways and the composition of airborne fission product iodine mixtures and their bearing on environmental exposure are discussed on the basis of measured fission product iodine emissions. The sorbents which can be used for iodine filtration, their removal efficiencies and range of applications are dealt with in detail. The particular conditions governing iodine removal, which are determined by the various gaseous iodine species, are illustrated on the basis of experimentally determined retention profiles. Particular attention is given to the limitations imposed by temperature, humidity, radiation and filter poisoning. The types of filter normally used are described, their advantages and drawbacks discussed, the principles underlying their design are outlined and the sources of error indicated. The methods normally applied to test the efficiency of various iodine sorbents are described and assessed. Operating experience with iodine filters, gathered from surveillance periods of many years, is supplemented by a large number of test results and the findings of extensive experiments. Possible ways of prolonging the permissible service lives of iodine filters are discussed and information is given on protective measures. The various iodine removal processes applied in reprocessing plants are described and compared with reference to efficiency and cost. The latest developments in filter technology in reprocessing plants are briefly outlined

Facility effluent monitoring

Energy Technology Data Exchange (ETDEWEB)

Gleckler, B.P.

1995-06-01

This section of the 1994 Hanford Site Environmental Report summarizes the facility effluent monitoring programs and provides an evaluation of effluent monitoring data. These evaluations are useful in assessing the effectiveness of effluent treatment and control systems, as well as management practices.

Decontamination of two filter boxes after a fire

International Nuclear Information System (INIS)

Cerre, P.; Mestre, E.; Lafitte, T.

1961-01-01

As a primary filter of the venting system caught fire in a hot cell of the Laboratory of Examination of Irradiated Fuels, this filter (as well as the secondary filter) has been removed, wrapped in polyvinyl sheets, and transported into the decontamination station. The authors report the details of the handling and decontamination operations: modifications to the station arrangement, measures of radiation protection, decontamination and measurements, observations made when disassembling the filter and filter-boxes [fr

Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

Directory of Open Access Journals (Sweden)

J. Dańko

2011-04-01

Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

Assessing environmental risk of the retired filter bed area, Battelle West Jefferson

International Nuclear Information System (INIS)

Miller, S.F.; Thompson, M.D.; Glennon, M.A.

1997-04-01

Initial investigations conducted by the U.S. Department of Energy, Chicago Operations Office, and by Argonne National Laboratory used seismic refraction profiling, electrical resistivity depth sounding, conductivity profiling, magnetic gradiometry, and ground-penetrating radar to study environmental geophysics in the area of the Battelle West Jefferson site's radiologically contaminated retired filter beds. The investigators used a combination of nonintrusive technologies and innovative drilling techniques to assess environmental risk at the filter beds and to improve understanding of the geology of the Big Darby Creek floodplain. The geophysical investigation, which showed that the preferred groundwater pathway is associated with a laterally extensive deposit of silty sand to sand that is less than 12 ft deep in the floodplain area, also guided the location of cone penetrometer test sites and piezometer installation. Cone penetrometer testing was useful for comparing continuous logging data with surface geophysical data in establishing correlations among unconsolidated materials

A new stack effluent monitoring system at the Risoe Hot Cell plant

International Nuclear Information System (INIS)

Boetter-Jensen, L.; Hedemann Jensen, P.; Lauridsen, B.

1984-06-01

This report describes a new stack effluent monitoring system that has been installed at the Hot Cell facility. It is an integrating iodine/particulate system consisting of a γ-shielded flow house in which a continous air sample from the ventilation channel ia sucked through coal and glass filter papers. Activity is accumulated on the filter papers and a thin plastic scintillator detects the β-radiation from the trapped iodine or particulate activity. The stack effluent monitoring system has a two-step regulating function as applied to the ventilation system, first switching it to a recirculating mode, and finally to building-seal after given releases of 131 I. The collection efficiency for iodine in form of elementary iodine (I 2 ) and methyliodide (CH 3 I) has been determined experimentally. The unwanted response from a noble gas release has also been determined from experiments. The noble gas response was determined from puff releases of the nuclide 41 Ar in the concrete cells. It is concluded that the iodine/particulate system is extremely sensitive and that it can easily detect iodine or particulate releases as low as a few MBq. A gamma monitor placed in connection with the iodine/particulate system detects Xe/Kr-releases as low as a few tens of MBq per second. (author)

Treatment and processing of the effluents and wastes (other than fuel) produced by a 900 MWe nuclear power plant

International Nuclear Information System (INIS)

Giraud

1983-01-01

Effluents produced by a 900 MWe power plant, are of three sorts: gaseous, liquid and solid. According to their nature, effluents are either released or stored for decaying before being released to the atmosphere. The non-contaminated reactor coolant effluents are purified (filtration, gas stripping) and treated by evaporation for reuse. Depending upon their radioactive level, liquid waste is either treated by evaporation or discharged after filtration. Solid waste issuing from previous treatments (concentrates, resins, filters) is processed in concrete drums using an encapsulation process. The concrete drum provides biological self-protection consistent with the national and international regulations pertaining to the transport of radioactive substance. Finally, the various low-level radioactive solid waste collected throughout the plant, is compacted into metal drums. Annual estimates of the quantity of effluents (gaseous, liquid) released in the environment and the number of drums (concrete, metal) produced by the plant figure in the conclusion

Removal of dissolved heavy metals from pre-settled stormwater runoff by iron-oxide coated sand (IOCS)

DEFF Research Database (Denmark)

Møller, J.; Ledin, Anna; Mikkelsen, Peter Steen

2002-01-01

(Pb=20, Cu=40, Zn=110, and Cr=15 ppb). Column experiments were conducted to test the influence of the infiltration rate (1 or 3 m/h) and the type of iron(hydr)oxide mineral (amorphous ferrihydrite and goethite coated sand). The results show that at least 90% of lead, copper and zinc can be removed......Sorption to iron-oxide coated sand (IOCS) is a promosing technology for removal of the dissolved heavy metal fraction in stormwater runoff. The development of a new technology is necessary since studies of stormwater runoff from traffic areas indicate that an oil separator and detention pond may...... by IOCS after 480 pore volumes. Control columns with uncoated filter sand show that lead, copper and zinc were removed with >95%, 35% and 5%, respectively. The removal of the negative metaloxy-ion, CrO4-3 was insignificant in both IOCS and sand columns at pH=7.7. Destruction of the columns after...

Collaborative learning in a culturally diverse secondary vocational education

NARCIS (Netherlands)

Dr. Rutger van de Sande; Drs. Kennedy Aquilino Tielman; Dr. S. Bolhuis; Prof. dr. Perry den Brok

2010-01-01

Collaborative learning in a culturally diverse secondary vocational education. By K. Tielman (Fontys), P. den Brok (ESoE), S. Bolhuis (Fontys) and R. van de Sande (Fontys) This contribution discusses a descriptive study on the experiences of students and teachers in secondary vocational education

Loading capacity of various filters for lithium fire generated aerosols

International Nuclear Information System (INIS)

Jeppson, D.W.; Barreca, J.R.

1980-01-01

The lithium aerosol loading capacity of a prefilter, HEPA filters and a sand and gravel bed filter was determined. The test aerosol was characterized and was generated by burning lithium in an unlimited air atmosphere. Correlation to sodium aerosol loading capacities were made to relate existing data to lithium aerosol loadings under varying conditions. This work is being conducted in support of the fusion reactor safety program. The lithium aerosol was generated by burning lithium pools, up to 45 kgs, in a 340 m 3 low humidity air atmosphere to supply aerosol to recirculating filter test loops. The aerosol was sampled to determine particle size, mass concentrations and chemical species. The dew point and gas concentrations were monitored throughout the tests. Loop inlet aerosol mass concentrations ranged up to 5 gr/m 3 . Chemical compounds analyzed to be present in the aerosol include Li 2 O, LiOH, and Li 2 CO 3 . HEPA filters with and without separators and a prefilter and HEPA filter in series were loaded with 7.8 to 11.1 kg/m 2 of aerosol at a flow rate of 1.31 m/sec and 5 kPa pressure drop. The HEPA filter loading capacity was determined to be greater at a lower flow rate. The loading capacity increased from 0.4 to 2.8 kg by decreasing the flow rate from 1.31 to 0.26 m/sec for a pressure drop of 0.11 kPa due to aerosol buildup. The prefilter tested in series with a HEPA did not increase the total loading capacity significantly for the same total pressure drop. Separators in the HEPA had only minor effect on loading capacity. The sand and gravel bed filter loaded to 0.50 kg/m 2 at an aerosol flow rate of 0.069 m/sec and final pressure drop of 6.2 kPa. These loading capacities and their dependence on test variables are similar to those reported for sodium aerosols except for the lithium aerosol HEPA loading capacity dependence upon flow rate

Acute effects of chlorpyryphos-ethyl and secondary treated effluents on acetylcholinesterase and butyrylcholinesterase activities in Carcinus maenas

Institute of Scientific and Technical Information of China (English)

Jihene Ghedira; Jamel Jebali; Zied Bouraoui; Mohamed Banni; Lassaad Chouba; Hamadi Boussetta

2009-01-01

The acute effects of commercial formulation of chlorpyrifos-ethyl (Dursban(r)) and the secondary treated industrial/urban effluent (STIUE) exposure on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities in hepatopancreas and gills of Mediterranean crab Carcinus maenas were investigated. After 2 d of exposure to chlorpyriphos-ethyl, the AChE activity was inhibited in both organs at concentrations of 3.12 and 7.82 μg/L, whereas the BuChE was inhibited only at higher concentration 7.82 μg/L of commercial preparation Dursban(r). The exposure of crabs to Dursban(r) (3.12 μg/L) showed a significant decrement of AChE activity at 24 and 48 h, whereas the BuChE was inhibited only after 24 h and no inhibition for both enzymes was observed after 72 h. Moreover, a significant repression of AChE activity was observed in both organs of C. maenas exposed to 5% of STIUE. Our experiments indicated that the measurement of AChE activity in gills and hepatopancreas of C. meanas would be useful biomarker of organophosphorous (OP) and of neurotoxic effects of STIUE in Tunisia.

Transport of 152Eu colloids in a system of fine sand and water containing humic substances

International Nuclear Information System (INIS)

Klotz, D.

1995-01-01

The migration of 152 Eu in a system of fine sand and water containing humic substances was investigated in a flow column system under realistic conditions. In this system, the trivalent Eu forms colloids with the water. These Eu humates are transported without retardation at recovery rates significantly below 100 per cent. Recovery is more or less a measure of the physical process of filtration of Eu bonded to particulates. In the range of natural filtering rates, the recovery rates decrease with decreasing filtering rate. (orig.) [de

Dark grains of sand: a geological storytelling

Science.gov (United States)

Gallo Maresca, Magda

2017-04-01

In the secondary Italian school the Earth science learning begins at first year, in synergy with other natural science subjects such as Astronomy, Chemistry and Biology. Italian teachers have to focus on the landscape geomorphological aspects and often Earth processes are difficult to display since they are related to certain phenomena happened during the past and often far from the involved country. In order to better understand the environment surrounding us, very simple and poor materials, like sands, allow the teachers to create attractive lab experiences. According to the IBSE (Inquiry Based Science Education) approach, a learning unit has been implemented starting from a walking along the light carbonate beaches of the Adriatic sea: a smart look to the sands ("engage step"), stroke the students fantasy pushing them to explore some strange black grains on the sands. Dirty sands? Or rock landscape, soil degradation and Ofanto river and coastal processes (erosion, transportation and deposition)? This was the teaching challenge. Due to the youngest age, a third level, guided inquiry, was adopted so the teacher is the "guide of inquiry" encouraging the students using the research question ("Why is the sand dark?", "Do all sands look the same?", "Where does it come from?") and driving the students around their investigation plans ("How can I measure grain size?"). A procedure to answer the above questions and validate the results and explanations has been implemented to allow the students to be proactive in their study. During the learning activities will be the students to ask for field trip to elaborate their new knowledge, verify and visualize the speculated processes. The teaching skills allow to address several geosciences domains such as mineralogy, petrology, regional geology and geodynamics as well as other scientific disciplines such as mathematics (more specifically statistics), forensic science and even life sciences (the presence of bioclasts might

Eastern Scheldt Sand, Baskarp Sand No. 15

DEFF Research Database (Denmark)

Andersen, A. T; Madsen, E. B.; Schaarup-Jensen, A. L.

The present data report contains data from 13 drained triaxial tests, performed on two different sand types in the Soil Mechanics Laboratory at Aalborg University in March, 1997. Two tests have been performed on Baskarp Sand No. 15, which has already ken extensively tested in the Soil Mechanics...... Laboratory. The remaining 11 triaxial tests have ben performed on Eastern Scheldt Sand, which is a material not yet investigated at the Soil Mechanics Laboratory. In the first pari of this data report, the characteristics of the two sand types in question will be presented. Next, a description...... will described. In this connection, the procedure for preparation of the soil specimens will be presented, and the actual performance of the tests will be briefly outlined. Finally, the procedure for processing of the measurements from the laboratory in order to obtain usable data will be described. The final...

F/H Effluent Treatment Facility filtration upgrade alternative evaluations overview

Energy Technology Data Exchange (ETDEWEB)

Miles, W.C. Jr.; Poirier, M.R.; Brown, D.F.

1992-01-01

The F/H Effluent Treatment Facility (ETF) at the Savannah River Site (SRS) was designed to treat process wastewater from the 200-F/H Production Facilities (routine wastewater) as well as intermittent flows from the F/H Retention Basins and F/H Cooling Water Basins (nonroutine wastewater). Since start-up of the ETF at SRS in 1988, the treatment process has experienced difficulties processing routine and nonroutine wastewater. Studies have identified high bacteria and bacterial decomposition products in the wastewater as the cause for excessive fouling of the filtration system. In order to meet Waste Management requirements for the treatment of processed wastewater, an upgrade of the ETF filtration system is being developed. This upgrade must be able to process the nonroutine wastewater at design capacity. As a result, a study of alternative filter technologies was conducted utilizing simulated wastewater. The simulated wastewater tests have been completed. Three filter technologies, centrifugal polymeric ultrafilters, tubular polymeric ultrafilters, and backwashable cartridge filters have been selected for further evaluation utilizing actual ETF wastewater.

F/H Effluent Treatment Facility filtration upgrade alternative evaluations overview

Energy Technology Data Exchange (ETDEWEB)

Miles, W.C. Jr.; Poirier, M.R.; Brown, D.F.

1992-07-01

The F/H Effluent Treatment Facility (ETF) at the Savannah River Site (SRS) was designed to treat process wastewater from the 200-F/H Production Facilities (routine wastewater) as well as intermittent flows from the F/H Retention Basins and F/H Cooling Water Basins (nonroutine wastewater). Since start-up of the ETF at SRS in 1988, the treatment process has experienced difficulties processing routine and nonroutine wastewater. Studies have identified high bacteria and bacterial decomposition products in the wastewater as the cause for excessive fouling of the filtration system. In order to meet Waste Management requirements for the treatment of processed wastewater, an upgrade of the ETF filtration system is being developed. This upgrade must be able to process the nonroutine wastewater at design capacity. As a result, a study of alternative filter technologies was conducted utilizing simulated wastewater. The simulated wastewater tests have been completed. Three filter technologies, centrifugal polymeric ultrafilters, tubular polymeric ultrafilters, and backwashable cartridge filters have been selected for further evaluation utilizing actual ETF wastewater.

F/H effluent treatment facility filtration upgrade alternative evaluations overview

International Nuclear Information System (INIS)

Miles, W.C. Jr.; Poirier, M.R.; Brown, D.F.

1992-01-01

The F/H Effluent Treatment Facility (ETF) at the Savannah River Site (SRS) was designed to treat process wastewater from the 200-F/H Production Facilities (routine wastewater) as well as intermittent flows from the F/H Retention Basins and F/H Cooling Water Basins (nonroutine wastewater). Since start-up of the ETF at SRS in 1988, the treatment process has experienced difficulties processing routine and nonroutine wastewater. Studies have identified high bacteria and bacterial decomposition products in the wastewater as the cause for excessive fouling of the filtration system. In order to meet Waste Management requirements for the treatment of processed wastewater, an upgrade of the ETF filtration system is being developed. This upgrade must be able to process the nonroutine wastewater at design capacity. As a result, a study of alternative filter technologies was conducted utilizing simulated wastewater. The simulated wastewater tests have been completed. Three filter technologies, centrifugal polymeric ultrafilters, tubular polymeric ultrafilters, and backwashable cartridge filters have been selected for further evaluation utilizing actual ETF wastewater. (author)

Vertical flow soil filter for the elimination of micro pollutants from storm and waste water

DEFF Research Database (Denmark)

Janzen, Niklas; Banzhaf, Stefan; Scheytt, Traugott

2009-01-01

A technical scale activated soil filter has been used to study the elimination rates of diverse environmentally relevant micro pollutants from storm and waste water. The filter was made of layers of peat, sand and gravel. The upper (organic) layer was planted with reed (phragmites australis......) to prevent clogging and was spiked with activated sludge to enhance microbial biomass and biodegradation potential. Compounds used as UV filters, antioxidants or plasticizers, namely 4-methylbenzylidene camphor (4-MBC), benzophenone-3 (BP-3), butylated hydroxytoluene (BHT), N-butylbenzenesulfonamide (NBBS...

Laboratory measurement of secondary pollutant yields from ozone reaction with HVAC filters

International Nuclear Information System (INIS)

Destaillats, Hugo; Chen, Wenhao; Apte, Michael; Li, Nuan; Spears, Michael; Almosni, Jeremie; Zhang, Jianshun Jensen; Fisk, William J.

2009-01-01

We used Proton Transfer Reaction - Mass Spectrometry (PTR-MS) and conventional sampling methods to monitor and identify trace level organic pollutants formed in heterogeneous reactions between ozone and HVAC filters in real time. Experiments were carried out using a bench-scale flow tube reactor operating with dry air and humidified air (50% RH), at realistically high ozone concentrations (150 ppbv). We explored different filter media (i.e., fiberglass and cotton/polyester blends) and different particle loadings (i.e., clean filter and filters loaded with particles for 3 months at the Lawrence Berkeley National Laboratory and the Port of Oakland, CA). Detailed emission dynamics of very low levels of certain organic pollutants from filter media upon ozone exposure in the presence of moisture have been obtained and analyzed.

Elimination of micropollutants and transformation products from a wastewater treatment plant effluent through pilot scale ozonation followed by various activated carbon and biological filters.

Science.gov (United States)

Knopp, Gregor; Prasse, Carsten; Ternes, Thomas A; Cornel, Peter

2016-09-01

Conventional wastewater treatment plants are ineffective in removing a broad range of micropollutants, resulting in the release of these compounds into the aquatic environment, including natural drinking water resources. Ozonation is a suitable treatment process for micropollutant removal, although, currently, little is known about the formation, behavior, and removal of transformation products (TP) formed during ozonation. We investigated the elimination of 30 selected micropollutants (pharmaceuticals, X-ray contrast media, industrial chemicals, and TP) by biological treatment coupled with ozonation and, subsequently, in parallel with two biological filters (BF) or granular activated carbon (GAC) filters. The selected micropollutants were removed to very different extents during the conventional biological wastewater treatment process. Ozonation (specific ozone consumption: 0.87 ± 0.29 gO3 gDOC(-1), hydraulic retention time: 17 ± 3 min) eliminated a large number of the investigated micropollutants. Although 11 micropollutants could still be detected after ozonation, most of these were eliminated in subsequent GAC filtration at bed volumes (BV) of approximately 25,000 m(3) m(-3). In contrast, no additional removal of micropollutants was achieved in the BF. Ozonation of the analgesic tramadol led to the formation of tramadol-N-oxide that is effectively eliminated by GAC filters, but not by BF. For the antiviral drug acyclovir, the formation of carboxy-acyclovir was observed during activated sludge treatment, with an average concentration of 3.4 ± 1.4 μg L(-1) detected in effluent samples. Subsequent ozonation resulted in the complete elimination of carboxy-acyclovir and led to the formation of N-(4-carbamoyl-2-imino-5-oxo imidazolidin)-formamido-N-methoxyacetetic acid (COFA; average concentration: 2.6 ± 1.0 μg L(-1)). Neither the BF nor the GAC filters were able to remove COFA. These results highlight the importance of considering TP in the

Liquid secondary waste. Waste form formulation and qualification

Energy Technology Data Exchange (ETDEWEB)

Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Dixon, K. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hill, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); King, W. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nichols, R. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2016-03-01

The Hanford Site Effluent Treatment Facility (ETF) currently treats aqueous waste streams generated during Site cleanup activities. When the Hanford Tank Waste Treatment and Immobilization Plant (WTP) begins operations, a liquid secondary waste (LSW) stream from the WTP will need to be treated. The volume of effluent for treatment at the ETF will increase significantly. Washington River Protection Solutions is implementing a Secondary Liquid Waste Immobilization Technology Development Plan to address the technology needs for a waste form and solidification process to treat the increased volume of waste planned for disposal at the Integrated Disposal Facility IDF). Waste form testing to support this plan is composed of work in the near term to demonstrate the waste form will provide data as input to a performance assessment (PA) for Hanford’s IDF.

The recovery of rare earth elements (REE) from beach sands

International Nuclear Information System (INIS)

Petrache, Cristina A.; Santos, Gabriel P. Jr.; Fernandez, Lourdes G.; Castillo, Marilyn K.; Tabora, Estrellita U; Intoy, Socorro P.; Reyes, Rolando Y.

2005-01-01

This preliminary study describes a metallurgical process that will extract, recover and produce REE oxides from beach sands obtained from Ombo, San Vicente, northern Palawan. The beach sands contain REE minerals of allanite and small amounts of monazite. Allanite is a sorosilicate mineral containing rare earths, thorium and uranium. Monazite is the anhydrous phosphate of cerium and the lanthanum group of rare earths with thorium commonly present in replacement for cerium and lanthanum. Collected beach sand were first pan-concentrated in-situ to produce heavy mineral concentrates. Screening using a 32 mesh (0.500 mm) sieve was done at the Nuclear Materials Research Laboratory to remove oversize sand particles. The -32 mesh fraction was treated with bromoform (sp. gr. 2.89) to separate the heavy minerals from siliceous gangue. Grinding to -325 mesh size (0.044mm) followed to liberate the minerals prior to leaching. Two acids leachants were used - concentrated HCl for the first trial and a mixture of concentrated HCl and HNO 3 (10:1 volume ratio) for the second trial. Both leaching trials were carried out at 180 o C for 7 hours or until dry. The resulting leached residues were re-dissolved in concentrated HCl and filtered. Ionquest R 801, an organophosphorous extractant, was added to the filtrate to separate the radioactive thorium from REE. Sodium hydroxide was added to the aqueous phase to precipitate the REE. After filtering the precipitate, it was dissolved in HCl. The acid solution was repeatedly extracted three (3) times with Ionquest R 801 to remove iron and other contaminants. Ammonium hydroxide was added to the final solution to precipitate the REE, which was then dried in the oven. The precipitate was calcined/roasted in the furnace at two different temperatures for different periods of time to burn off the organic matter and to form oxides. Results of the XRD analysis showed peaks of the calcined precipitate matching with the peaks of lanthanum oxide

Microbial community structure and a core microbiome in biological rapid sand filters at Danish waterworks

DEFF Research Database (Denmark)

Gülay, Arda; Musovic, Sanin; Albrechtsen, Hans-Jørgen

Rapid sand filtration is a traditional and common technology for drinking water purification from groundwater. Despite its wide scale and long-term use, the diversity and characterization of microbial communities in these engineered systems have remained unexplored and their roles in removal perf...

Sand flies naturally infected by Leishmania (L.) mexicana in the peri-urban area of Chetumal city, Quintana Roo, México.

Science.gov (United States)

Sánchez-García, Laura; Berzunza-Cruz, Miriam; Becker-Fauser, Ingeborg; Rebollar-Téllez, Eduardo A

2010-06-01

The surveillance of prevalent Leishmania sand fly vectors is an important issue for epidemiological studies in populated areas where leishmaniasis is endemic. In this study, we collected sand flies from a peri-urban area in the southeast of Mexico. Natural infection with Leishmania (L.) mexicana was studied by PCR using a Leishmania internal transcribed spacer of the ribosomal RNA gene for amplification. Infected Lutzomyia olmeca olmeca, Lu. shannoni and Lu. cruciata sand flies were collected mainly during the high transmission season (November to March), coinciding with the highest sand fly densities. Additionally, positive specimens of Lu. olmeca olmeca were also captured during July and August. The infected sand flies were from primary forest (subperennial forest) and secondary forest (18-25 years old and 10-15 years old respectively). Sand flies collected with Disney and Shannon traps were the ones found to be infected with L. (L.) mexicana. We conclude that the high-risk period in which L. (L.) mexicana is transmitted in the peri-urban area of Chetumal City is from July to March and that transmission is associated with both the subperennial forest and the secondary forest. 2010 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

Understanding AL-PAM assisted oil sands tailings treatment

Energy Technology Data Exchange (ETDEWEB)

Guo, L.; Maham, Y.; Masliyah, J.; Xu, Z. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

2010-07-01

Technologies currently used to treat oil sands tailings include the composite tailings (CT) process and the thickened tailings (TT) or paste technology process. This PowerPoint presentation discussed a flocculation and filtration method used to produce stackable tailings deposits. Magnafloc 1011 and AL-PAM additions were used as part of the filtration technique to produce very dry filter cakes. The effect of AL-PAM molecular weight and aluminum content on tailings treatments was investigated as well as the effect of tailings characteristics on the performance of flocculant-assisted tailings filtration processes. The AL-PAM molecular structure was studied. An experimental study was conducted to determine the effect of various polymer additions on fresh tailings from an oil sands plant. The study showed that the optimum dosage for settling and filtration was lower for higher molecular weight AL-PAM. A higher aluminum content was beneficial for settling. Increases in the aluminum content did not improve filtration rates, but reduced optimal dosages. Step-by-step details of the supernatant filtration process were provided, as well as photographs of the laboratory study. tabs., figs.

Effects of UV light disinfection on antibiotic-resistant coliforms in wastewater effluents

International Nuclear Information System (INIS)

Meckes, M.C.

1982-01-01

Total coliforms and total coliforms resistant to streptomycin, tetracycline, or chloramphenicol were isolated from filtered activated sludge effluents before and after UV light irradiation. Although the UV irradiation effectively disinfected the wastewater effluent, the percentage of the total surviving coliform population resistant to tetracycline or chloramphenicol was significantly higher than the percentage of the total coliform population resistant to those antibiotics before UV irradiation. This finding was attributed to the mechanism of R-factor mediated resistance to tetracycline. No significant difference was noted for the percentage of the surviving total coliform population resistant to streptomycin before or after UV irradiation. Multiple drug resistant to patterns of 300 total coliform isolates revealed that 82% were resistant to two or more antibiotics. Furthermore, 46% of these isolates were capable of transferring antibiotic resistance to a sensitive strain of Escherichia coli

Substance Flow Analysis and Source Mapping of Chemical UV-filters

International Nuclear Information System (INIS)

Eriksson, E.; Andersen, H. R.; Ledin, A.

2008-01-01

Chemical ultraviolet (UV)-filters are used in sunscreens to protect the skin from harmful UV radiation which may otherwise cause sunburns and skin cancer. Commonly used chemical UV-filters are known to cause endocrine disrupting effects in both aquatic and terrestrial animals as well as in human skin cells. Here, source mapping and substance flow analysis were applied to find the sources of six UV-filters (oxybenzone, avobenzone, 4-methylbenzylidene camphor, octyl methoxycinnamate, octyl dimethyl PABA and homosalate) and to identify the most dominant flows of these substances in Denmark. Urban water, composed of wastewater and surface waters, was found to be the primary recipient of UV-filters, whereby wastewater received an estimated 8.5-65 tonnes and surface waters received 7.1-51 tonnes in 2005. In wastewater treatment plants, their sorption onto sludge is perceived to be an important process and presence in effluents can be expected due to a lack of biodegradability. In addition, the use of UV-filters is expected to continue to increase significantly. Not all filters (e.g., octyl dimethyl PABA and homosalate) are used in Denmark. For example, 4-MBC is mainly associated with self-tanning liquids and private import of sunscreens

Substance Flow Analysis and Source Mapping of Chemical UV-filters

Energy Technology Data Exchange (ETDEWEB)

Eriksson, E., E-mail: eve@env.dtu.dk; Andersen, H. R.; Ledin, A. [Technical University of Denmark, Department of Environmental Engineering (Denmark)

2008-12-15

Chemical ultraviolet (UV)-filters are used in sunscreens to protect the skin from harmful UV radiation which may otherwise cause sunburns and skin cancer. Commonly used chemical UV-filters are known to cause endocrine disrupting effects in both aquatic and terrestrial animals as well as in human skin cells. Here, source mapping and substance flow analysis were applied to find the sources of six UV-filters (oxybenzone, avobenzone, 4-methylbenzylidene camphor, octyl methoxycinnamate, octyl dimethyl PABA and homosalate) and to identify the most dominant flows of these substances in Denmark. Urban water, composed of wastewater and surface waters, was found to be the primary recipient of UV-filters, whereby wastewater received an estimated 8.5-65 tonnes and surface waters received 7.1-51 tonnes in 2005. In wastewater treatment plants, their sorption onto sludge is perceived to be an important process and presence in effluents can be expected due to a lack of biodegradability. In addition, the use of UV-filters is expected to continue to increase significantly. Not all filters (e.g., octyl dimethyl PABA and homosalate) are used in Denmark. For example, 4-MBC is mainly associated with self-tanning liquids and private import of sunscreens.

Applicability study on a ceramic filter with hot-test conducted in a BWR plant

International Nuclear Information System (INIS)

Yamada, K.; Shirai, T.; Wada, M.; Nakamizo, H.

1991-01-01

Radioactive crud removal and filtration performance recovery by backwashing were examined with a BWR plant pool water using a ceramic filter element, 0.1 micron in nominal pore size and 0.2m 2 in filtration area. Totally 1114 hours filter operation were accumulated. Ten backwashings were accomplished during the test period. The following results were obtained. (1) Radioactive crud concentration in the filter effluent remained below 10 5 Bq/m 3 . (2) Both pressure loss through the filter and dose rate at the filter vessel surface were recovered to the initial level by each backwashing. The surface dose rate after backwashing was approximately 0.01mSv/h. According to these test results, it is confirmed that the ceramic filter is appropriate for the treatment of highly crud concentrated radioactive liquid, which is generated in nuclear facilities, such as spent fuel reprocessing plants. (author)

Treatment of liquid effluents from an ammonia/urea/sulphur plant

Energy Technology Data Exchange (ETDEWEB)

Padula, R.C.; Amabal, S.P.

1979-01-01

The effluent treatment processes planned for a new 1500 ton/day urea, 1200 ton/day ammonia plant in Brazil, based on the two-stage reaction of ammonia and carbon dioxide to form urea and on the catalytic hydrogenation of nitrogen to ammonia, will include the steps of equalization, flocculation, flotation, nitrification, sedimentation, denitrification, rapid aeration, further settlement, filtration, and discharge to a river. Sludge will be chemically conditioned as needed, and will be thickened, filtered, and disposed of by land application. There will be considerable recycling of nutrients.

Iodine speciation in the hot cell effluent gases

International Nuclear Information System (INIS)

Lee, B.S.; Jester, W.A.; Olynyk, J.M.

1990-01-01

The various species of airborne radioiodine can affect the iodine source term of a severe core damage accident because of the different transport and deposition properties. also, the radiobiological hazardness may vary according to their chemical form. The purpose of the work reported in this paper was to characterize the various chemical forms of airborne radioiodine in hot cell effluent gases of a radiopharmaceutical production facility that produces medical radioisotopes from separated fission products of irradiated uranium targets. It is concluded that the methyl iodide is the youngest chemical species in terms of effective decay time age, and the hot cell filter bank is least efficient in removing the methyl iodide

Thermal/chemical degradation of ceramic cross-flow filter materials

Energy Technology Data Exchange (ETDEWEB)

Alvin, M.A.; Lane, J.E.; Lippert, T.E.

1989-11-01

This report summarizes the 14-month, Phase 1 effort conducted by Westinghouse on the Thermal/Chemical Degradation of Ceramic Cross-Flow Filter Materials program. In Phase 1 expected filter process conditions were identified for a fixed-bed, fluid-bed, and entrained-bed gasification, direct coal fired turbine, and pressurized fluidized-bed combustion system. Ceramic cross-flow filter materials were also selected, procured, and subjected to chemical and physical characterization. The stability of each of the ceramic cross-flow materials was assessed in terms of potential reactions or phase change as a result of process temperature, and effluent gas compositions containing alkali and fines. In addition chemical and physical characterization was conducted on cross-flow filters that were exposed to the METC fluid-bed gasifier and the New York University pressurized fluidized-bed combustor. Long-term high temperature degradation mechanisms were proposed for each ceramic cross-flow material at process operating conditions. An experimental bench-scale test program is recommended to be conducted in Phase 2, generating data that support the proposed cross-flow filter material thermal/chemical degradation mechanisms. Papers on the individual subtasks have been processed separately for inclusion on the data base.

Processing of miscellaneous radioactive effluents by continous flocculation decantation

International Nuclear Information System (INIS)

Lundy, D.; Matton, P.; Petteau, J.L.; Roofthooft, R.

1985-01-01

In the nuclear power plant of Chooz an installation for flocculation and chemical precipitation has been built to treat miscellaneous radioactive effluents continuously. It is an industrial prototype of 5 m 3 /h resulting of several years of research, first on lab scale in a discontinous system and finally in a continuous pilot plant of small size (500 l/h). The process is based on the adsorption of radioactivity on a floc of copper-ferrocyanide precipitated by ferric chloride. The water is then filtered. After a series of preliminary tests and modifications, it has been possible to develop a technique which satisfies the specified decontamination conditions and to reduce the discharges of radioactivity to the Meuse to only 5 - 10% of the authorized limits. The process aims principally at the treatment of laundry waste, but other effluents such as drains from the rocks, pool water and used decontamination solutions (of the primary pumps) have been treated. A technico-economic evaluation of the process in comparison with evaporation is clearly in favour of the flocculation. 31 figs, 40 tables, 12 refs

Impact of Mars sand on dust on the design of space suits and life support equipment: A technology assessment

Science.gov (United States)

Simonds, Charles H.

1991-01-01

Space suits and life support equipment will come in intimate contact with Martian soil as aerosols, wind blown particles and material thrown up by men and equipment on the Martian surface. For purposes of this discussion the soil is assumed to consist of a mixture of cominuted feldspar, pyroxene, olivine, quartz, titanomagnetite and other anhydrous and hydrous iron bearing oxides, clay minerals, scapolite and water soluble chlorides and sulfates. The soil may have photoactivated surfaces that acts as a strong oxidizer with behavior similar to hydrogen peroxide. The existing data about the Mars soil suggests that the dust and sand will require designs analogous to those uses on equipment exposed to salty air and blowing sand and dust. The major design challenges are in developing high performance radiators which can be cleaned after each EVA without degradation, designing seals that are readily cleaned and possibly in selecting materials which will not be degraded by any strong oxidants in the soil. The magnitude of the dust filtration challenge needs careful evaluation in terms of the trade off between fine-particle dust filters with low pressure drop that are either physically large and heavy, like filter baghouses require frequent replacement of filter elements, of low volume high pressure thus power consumption approaches, or washable filters. In the latter, filter elements are cleaned with water, as could the outsides of the space suits in the airlock.

Impact of Mars sand on dust on the design of space suits and life support equipment: A technology assessment

Science.gov (United States)

Simonds, Charles H.

1991-05-01

Space suits and life support equipment will come in intimate contact with Martian soil as aerosols, wind blown particles and material thrown up by men and equipment on the Martian surface. For purposes of this discussion the soil is assumed to consist of a mixture of cominuted feldspar, pyroxene, olivine, quartz, titanomagnetite and other anhydrous and hydrous iron bearing oxides, clay minerals, scapolite and water soluble chlorides and sulfates. The soil may have photoactivated surfaces that acts as a strong oxidizer with behavior similar to hydrogen peroxide. The existing data about the Mars soil suggests that the dust and sand will require designs analogous to those uses on equipment exposed to salty air and blowing sand and dust. The major design challenges are in developing high performance radiators which can be cleaned after each EVA without degradation, designing seals that are readily cleaned and possibly in selecting materials which will not be degraded by any strong oxidants in the soil. The magnitude of the dust filtration challenge needs careful evaluation in terms of the trade off between fine-particle dust filters with low pressure drop that are either physically large and heavy, like filter baghouses require frequent replacement of filter elements, of low volume high pressure thus power consumption approaches, or washable filters. In the latter, filter elements are cleaned with water, as could the outsides of the space suits in the airlock.

Submarine sand ridges and sand waves in the eastern part of the China Sea

Science.gov (United States)

Wu, Ziyin; Li, Shoujun; Shang, Jihong; Zhou, Jieqiong; Zhao, Dineng; Liang, Yuyang

2016-04-01

Integrated with multi-beam and single-beam echo sounding data, as well as historical bathymetric data, submarine bathymetric maps of the eastern part of the China Sea, including the Bohai Sea, Huanghai Sea, and East China Sea, are constructed to systematically study submarine sand ridges and sand waves in the eastern part of the China Sea, combined with high-resolution seismic, sub-bottom profile and borehole data. Submarine sand ridges are extraordinarily developed in the eastern part of the China Sea, and 7 sand ridge areas can be divided from north to south, that is, the Laotieshan Channel sand ridge area in the Bohai Sea, the Korea Bay sand ridge area in the southern Huanghai Sea, the sand ridge area in the eastern Huanghai islands and the Huanghai Troughs, the Jianggang sand ridge area in the western Huanghai Sea, the sand ridge area in the East China Sea shelf, and the sand ridge and sand wave area in the Taiwan Strait and Taiwan Banks. The distribution area of the sand ridges and sand waves covers more than 450,000 km2, wherein ~10,000 km2 in the Bohai Bay, ~200,000 km2 in the Huanghai Sea, ~200,000 km2 in the East China Sea shelf, and ~40,000 km2 in the Taiwan Strait and Taiwan Banks, respectively. The great mass of sand ridges are distributed within water depth of 5-160 m, with a total length of over 160 km and a main width of 5-10 km. The inner structure of the sand ridges presents features of high-angle inclined beddings, with main lithology of sands, sand-mud alternations partly visible, and a small number of mud cores. Dating results indicate that the sand ridges in the eastern part of the China Sea are mainly developed in the Holocene. Sea-level variation dominates the sand ridge evolution in the eastern part of the China Sea since the LGM, and the sand ridges developed in the area of < 60m water depth are appeared in bad activity, meanwhile sand ridges with good activity are still developed in large scale.

Treatment of synthetic urban runoff using manganese oxide-coated sand in the presence of magnetic field

Directory of Open Access Journals (Sweden)

Maryam Foroughi

2013-01-01

Conclusion: Manganese oxide-coated sand filter in the presence of magnetic field improve the quality of urban runoff significantly. Authors believe that this approach is simple, economical and efficient as in comparison to other existing methods. This could be a promising treatment technology that can enhance quality of urban runoff and industrial wastewaters.

Long-term field-scale experiment on using lime filters in an agricultural catchment.

Science.gov (United States)

Kirkkala, Teija; Ventelä, Anne-Mari; Tarvainen, Marjo

2012-01-01

The River Yläneenjoki catchment in southwest Finland is an area with a high agricultural nutrient load. We report here on the nutrient removal performance of three on-site lime-sand filters (F1, F2, and F3), established within or on the edge of the buffer zones. The filters contain burnt lime (CaO) or spent lime [CaO, Ca(OH), and CaCO]. Easily soluble lime results in a high pH level (>11) and leads to an efficient precipitation of soluble phosphorus (P) from the runoff. Water samples were taken from the inflow and outflow of each site in different hydrological situations. The length of the monitoring period was 4 yr for F1, 6 yr for F2, and 1.5 yr for F3. F1 and F2 significantly reduced the suspended solids (SS), total P (PTOT), and dissolved reactive P (DRP) in the treated water. The proportional reduction (%) varied but was usually clearly positive. Filter F3 was divided into two equal parts, one containing burnt lime and the other spent lime. Both filter parts removed PTOT and SS efficiently from the water; the burnt-lime part also removed DRP. The mixed-lime part removed DRP for a year, but then the efficiency decreased. The effect of filters on nitrogen compounds varied. We conclude that sand filters incorporating lime can be used together with buffer zones to reduce both P and SS load to watercourses. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Measurements of oxygenated volatile organic compounds in the oil sands region of Alberta

Science.gov (United States)

Moussa, S. G.; Leithead, A.; Li, S. M.; Gordon, M.; Hayden, K. L.; Wang, D. K.; Staebler, R. M.; Liu, P.; O'Brien, J.; Mittermeier, R.; Liggio, J.

2014-12-01

Oxygenated volatile organic compounds (OVOCs) are ubiquitous in the atmosphere, and represent an important fraction of volatile organic compounds. Additionally some OVOC species may pose health risks. OVOCs can affect the oxidative and radiative budget of the atmosphere since they are precursors to ground level ozone, hydroxyl radicals and secondary organic aerosols (SOA). OVOCs such as methanol, formaldehyde, acetaldehyde, acetone, crotonaldehyde, methylvinylketone (MVK), methylethylketone (MEK) and acrolein can be emitted from anthropogenic and biogenic sources. Additionally, they are the secondary products of the photo-oxidation of hydrocarbons (biogenic and anthropogenic). Understanding the magnitude of these sources is a prerequisite for accurate representations of radical cycling, ozone production and SOA formation in air quality models. The sources of OVOCs in the Alberta Oil Sands (OS) region have not previously been well characterized. In the summer of 2013, airborne measurements of various OVOCs were made in the Athabasca oil sands region between August 13 and September 7, 2013. Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) was used to measure methanol, formaldehyde, acetaldehyde, acetone, crotonaldehyde, MVK, MEK, acrolein as well as other hydrocarbons. Emission ratios (ER) for several OVOCs (relative to carbon monoxide; CO) were used to estimate direct anthropogenic emissions from OS industrial sources, while the calculated OH radical exposures were used to estimate the production and removal of secondary anthropogenic OVOCs. The results indicate that OVOCs such as acetaldehyde, crotonaldehyde and MVK have both primary and secondary anthropogenic and biogenic sources. However, species such as methanol and acrolein are from biogenic and anthropogenic sources, respectively. The results of this work will help to characterize sources of OVOCs and the factors influencing their atmospheric fate in the Oil Sands region.

Upgrading secondary wastewater plant effluent by modified coagulation and flocculation, for water reuse in irrigation

Directory of Open Access Journals (Sweden)

Mohammad Taghi Ghaneian

2017-09-01

Full Text Available In this study, the feasibility of using coagulation, flocculation, and sedimentation (CF-S for advanced treatment of secondary effluent released from the Yazd Intermittent Cycle Extended Aeration System was investigated. Four coagulants including ferric chloride (FeCl3, polyaluminum chloride (PAC, ferrous sulfate (FeSo4, and potassium ferrate (K2FeSo4 along with Gflog C-150 as flocculant polymer were used. In this study, returned chemical sludge was considered as a modification. Preliminary CF-S processes showed that FeSO4 and K2FeO4 had low removal efficiencies. Thus, these two coagulants were abandoned and CF-S processes were continued only with PAC and FeCl3 coagulants which had higher efficiencies in the removal of biological oxygen demand (BOD5, chemical oxygen demand (COD, total suspended solids (TSS, and turbidity. Removal efficiency was higher when half of the chemical producing sludge was returned as compared with using both coagulants simultaneously along with 2 mg L−1 of C-150 as flocculant. In the optimum dosage, when half of PAC and FeCl3 sludge were returned, the volume of produced sludge was reduced by 40% and 28%, respectively, as compared without returned sludge. For the PAC coagulant in the optimum dosage with half of the sludge returned, all 2012 EPA standards of irrigation were met for both ‘processed and non-processed type’ agricultural crops.

Secondary wastewater treatment by microalgae isolated from ...

African Journals Online (AJOL)

Microalgae play a fundamental role in primary and secondary wastewater treatment. In this work the growth, photosynthetic activity and removal of phosphorus from wastewater effluents by indigenous blue-green algal species, Spirulina and Oscillatoria, isolated from Gaborone oxidation ponds was studied. Oscillatoria and ...

Fate of wastewater effluent hER-agonists and hER-antagonists during soil aquifer treatment.

Science.gov (United States)

Otakuye, Conroy; Quanrud, David M; Ela, Wendell P; Wicke, Daniel; Lansey, Kevin E; Arnold, Robert G

2005-04-01

Estrogen activity was measured in wastewater effluent before and after polishing via soil-aquifer treatment (SAT) using both a (hER-beta) competitive binding assay and a transcriptional activation (yeast estrogen screen, YES) assay. From the competitive binding assay, the equivalent 17alpha-ethinylestradiol (EE2) concentration in secondary effluent was 4.7 nM but decreased to 0.22 nM following SAT. The YES assay indicated that the equivalent EE2 concentration in the same effluent sample was below the method-detection limit (bioassays alone should not be relied upon to measure estrogenic activity in complex environmental samples because the simultaneous presence of both agonists and antagonist compounds can yield false negatives. Multiple in vitro bioassays, sample fractionation or tests designed to measure anti-estrogenic activity can be used to overcome this problem. It is also clear that there are circumstances under which SAT does not completely remove estrogenic activity during municipal wastewater effluent polishing.

Assessment of refinery effluents and receiving waters using biologically-based effect methods

International Nuclear Information System (INIS)

2012-01-01

Within the EU it is apparent that the regulatory focus on the use of biologically-based effects methods in the assessment of refinery effluents and receiving waters has increased in the past decade. This has been reflected in a recent refinery survey which revealed an increased use of such methods for assessing the quality of refinery effluents and their receiving waters. This report provides an overview of recent techniques used for this purpose. Several case studies provided by CONCAWE member companies describe the application of biological methods to effluent discharge assessment and surface water monitoring. The case studies show that when biological methods are applied to refinery effluents and receiving waters they raise different questions compared with those obtained using physical and chemical methods. Although direct measurement of the toxicity of effluent and receiving to aquatic organisms is the most cited technique, more recent efforts include tests that also address the persistence of effluent toxicity once discharged into the receiving water. Similarly, ecological monitoring of receiving waters can identify effects of effluent inputs arising from species interactions and other secondary effects that would not always be apparent from the results of biological tests conducted on single aquatic organisms. In light of recent and proposed regulatory developments the objectives of this report are therefore to: Discuss the application of biologically-based effects methods (including ecological monitoring) to refinery discharges and receiving waters; Assess the implications of such methods for future regulation of refinery discharges; and Provide guidance on good practice that can be used by refineries and the downstream oil industry to carry out and interpret data obtained using biologically-based effects methods. While the emphasis is on the toxic effects of effluents, other properties will also be covered because of their interdependency in determining

Assessment of refinery effluents and receiving waters using biologically-based effect methods

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-01-15

Within the EU it is apparent that the regulatory focus on the use of biologically-based effects methods in the assessment of refinery effluents and receiving waters has increased in the past decade. This has been reflected in a recent refinery survey which revealed an increased use of such methods for assessing the quality of refinery effluents and their receiving waters. This report provides an overview of recent techniques used for this purpose. Several case studies provided by CONCAWE member companies describe the application of biological methods to effluent discharge assessment and surface water monitoring. The case studies show that when biological methods are applied to refinery effluents and receiving waters they raise different questions compared with those obtained using physical and chemical methods. Although direct measurement of the toxicity of effluent and receiving to aquatic organisms is the most cited technique, more recent efforts include tests that also address the persistence of effluent toxicity once discharged into the receiving water. Similarly, ecological monitoring of receiving waters can identify effects of effluent inputs arising from species interactions and other secondary effects that would not always be apparent from the results of biological tests conducted on single aquatic organisms. In light of recent and proposed regulatory developments the objectives of this report are therefore to: Discuss the application of biologically-based effects methods (including ecological monitoring) to refinery discharges and receiving waters; Assess the implications of such methods for future regulation of refinery discharges; and Provide guidance on good practice that can be used by refineries and the downstream oil industry to carry out and interpret data obtained using biologically-based effects methods. While the emphasis is on the toxic effects of effluents, other properties will also be covered because of their interdependency in determining

Nitrogen Removal in a Full-Scale Domestic Wastewater Treatment Plant with Activated Sludge and Trickling Filter

Directory of Open Access Journals (Sweden)

Davood Nourmohammadi

2013-01-01

Full Text Available During the last decade, more stringent effluent requirements concerning the nutrients effluent values have been imposed by legislation and social concern. In this study, efficiency of total nitrogen removal in activated sludge and trickling filter processes (AS/TF was investigated in Tehran North wastewater treatment plant. Biological system in this site was included, anoxic selector tank, aeration tank, final sedimentation, and trickling filter. A part of treated wastewater before chlorination was mixed with supernatant of dewatered sludge and fed to the trickling filter. Supernatant of dewatered sludge with high concentration of NH4-N was diluted by treated wastewater to provide complete nitrification in trickling filter Produced nitrate in trickling filter was arrived to the anoxic tank and converted to nitrogen gas by denitrification. According to the study result, low concentration of organic carbone and high concentration of NH4-N led to nitrification in TF, then nitrate denitrification to nitrogen gas occurred in selector area. NH4-N concentration decreased from 26.8 mg/L to 0.29 mg/L in TF, and NO3-N concentration increased from 8.8 mg/L to 27 mg/L in TF. Consequently, the total nitrogen decreased approximately to 50% in biological process. This efficiency has been observed in returned flow around 24% from final sedimentation into TF. It was concluded that, in comparison with biological nutrient removal processes, this process is very efficient and simple.

Polymer aids for settling and filtration of oil sands tailings

Energy Technology Data Exchange (ETDEWEB)

Wang, X. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Energy Resources Conservation Board, Calgary, AB (Canada). Oil Sands Section; Xu, Z.; Masliyah, J.H. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

2008-07-01

Oil sand tailings are segregated into coarse and fine tailings. High volumes of toxic fluids and tailings are created in the process. Tailings ponds are an environmental risk with high operating and maintenance costs. Current commercial technologies uses chemical additions to create recycled water and composite tailings (CT). Researchers are now investigating centrifuged and dry mature fine tailings (MFT). Filtration processes with flocculants are used to separate the tailings into warm recycle water and dried cakes that can be used in reclamation processes. Studies are being conducted to find a polymer than can effectively flocculate and filter whole oil sands tailings. The filtration procedure uses pressure to produce released water. Polymers include magnafloc and Al-PAM polymer concentrations are used in slurry masses. Tests have been conducted to determine the settling rates of the polymers. The tests showed that Al-PAM filtered the tailings effectively. Paraffinic froth treatment tests have also been conducted to determine settling rates. A cake produced with froth treatment tailings of Al-PAM 400 ppm had a water content 42.5 wt per cent. The tests showed that while Magnafloc 1011 is a good settling aid, but a poor filtration addition. Al-PAM aided in both the flocculation and filtration processes. Higher Al-PAM dosages are needed for froth treatment tailings processes. It was concluded that dry cakes are produced with the addition of Al-PAM. tabs., figs.

Electrochemical degradation of a real textile effluent using boron-doped diamond or β-PbO2 as anode

International Nuclear Information System (INIS)

Aquino, Jose M.; Pereira, Gabriel F.; Rocha-Filho, Romeu C.; Bocchi, Nerilso; Biaggio, Sonia R.

2011-01-01

Highlights: · Diamond anode enables total abatement of a real textile effluent COD with low energy consumption. · Use of diamond anode enables excellent decolorization rate of effluent in the presence of Cl - ions. · Diamond anode might be an excellent option for electrochemical treatment of real textile effluents. · PbO 2 anode, due to low cost and easiness of preparation, may be an option to decolorize the effluents. - Abstract: Constant current electrolyses are carried out in a filter-press reactor using a boron-doped diamond (Nb/BDD) or a Ti-Pt/β-PbO 2 anode, varying current density (j) and temperature. The degradation of the real textile effluent is followed by its decolorization and chemical oxygen demand (COD) abatement. The effect of adding NaCl (1.5 g L -1 ) on the degradation of the effluent is also investigated. The Nb/BDD anode yields much higher decolorization (attaining the DFZ limit) and COD-abatement rates than the Ti-Pt/β-PbO 2 anode, at any experimental condition. The best conditions are j = 5 mA cm -2 and 55 o C, for the system's optimized hydrodynamic conditions. The addition of chloride ions significantly increases the decolorization rate; thus a decrease of more than 90% of the effluent relative absorbance is attained using an applied electric charge per unit volume of the electrolyzed effluent (Q ap ) of only about 2 kA h m -3 . Practically total abatement of the effluent COD is attained with the Nb/BDD anode using a Q ap value of only 7 kA h m -3 , with an energy consumption of about 30 kW h m -3 . This result allows to conclude that the Nb/BDD electrode might be an excellent option for the remediation of textile effluents.

Investigation of Water Holding Capacity of Sugarcane Mulch for Sand Dune Stabilization in Ahvaz

Directory of Open Access Journals (Sweden)

T. Jamili

2017-01-01

Full Text Available Introduction: Wind erosion is one of the most serious problems in southwest Iran. Fine-grained structure of sand dunes with not enough strong composition and their low moisture retention property make them susceptible to wind erosion. They lack organic matter and are considered inherently of low fertility (Ahmadi, 2002. Studies have shown that non-erodible materials which include bentonite clay (Diouf et al., 1990, ureamelamine formaldehyde and urea–formaldehyde with 0.25% sodium chloride (Lahalih and Ahmed, 1998, acids, enzymes, lignosulfonates, polymers, tree resins (Santoni et al., 2001, waterborne polymer emulsion (Al-Khanbashi and Abdalla, 2006, polyvinyl alcohol and a polyvinyl acetate emulsion (Newman et al., 2005; Han et al., 2007, ash and polyacrylamide (Yang and Zejun, 2012.have significant potential in reducing wind erosion The area under farming of sugarcane in Khuzestan, Iran, is more than 130,000, ha. Vinasse and Filter Kike are two organic ingredients of sugarcane residues which are generated as byproduct materials insugarcane processing. In recent years these residues have been released into the environment and cause it regarded as water pollutant. Over 800,000 m3 of Vinasse is annually stored in each agro-industry. Vinasse also is rich in K, Ca, and Mg with moderate amounts of P and N,and non toxic complexes or heavy metals. Filter Kike is another residue produced in huge amounts by the agro-industry that is composed of cellulosic substances, CaCO3, N, P, K, organic matter, and clay. Therefore, the objective of this research is to investigate the effect of sugarcane mulch on water holding capacity in soil. This study is performed to evaluate the feasibility of using sugarcane residues inproduce of ecofriendly mulches for environmental use. In order of achieving these goals, Vinase, Filter Cake, and clay soil from near the sand dunes were used as sugarcane mulches. Further comparison between traditional oil mulches and

Comammox Nitrospira are key nitrifiers in diverse groundwater-fed drinking water filters

DEFF Research Database (Denmark)

Fowler, Jane; Palomo, Alejandro; Smets, Barth F.

Nitrification is a dominant process in groundwater-fed rapid sand filters (RSFs) used for drinking water purification. Near complete removal of ammonium and nitrite is required in the EU and Denmark due to strict regulatory limits that enable high water stability in the distribution system. RSFs...... this work provides a new assay for the simultaneous detection of clade A and B comammox Nitrospira and expands our current knowledge of the diversity of comammox Nitrospira, while attempting to explain the success of comammox Nitrospira in these groundwater-fed filters....

Radiation purification of the chemical industry effluents and possibilities of realization of this method

International Nuclear Information System (INIS)

Petryaev, E.P.; Kovalevskaya, A.M.; Shlyk, V.G.; Savushkin, I.A.; Kazazyan, V.T.

1977-01-01

Radiation-chemical methods for synthetic fibre industry effluents purification from cyanides, sulphides and monomers, as well as for disinfection of circulation water and improvement in sedimental and filtering properties of waste active slurry in petrochemical industry are described. Chemical plant effluents are purified by 70-90% from cyanides at the dose rate of 0,3 - 0,5 Mrad, by 60 - 70% from sulphides and monomers at the dose of 0,2 Mrad. Circulation water of petroleum processing plant is disinfected at the dose of 0,08 Mrad; the rates of filtration and sedimentation of waste active slurry increase two and three fold, correspondingly, at the dose of 0,6 Mrad. The power of radiation sources required for the industrial realization of radiation purification of liquid wastes has been calculated

Fontainebleau Sand

DEFF Research Database (Denmark)

Leth, Caspar Thrane

2006-01-01

The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand.......The report is a summary of results from laboratory tests in the geotechncial research group on Fontainebleau sand....

Cesium removal from the fuel storage water at the Savannah River Site R-Building Disassembly Basin using 3M Empore reg-sign-membrane filter technology

International Nuclear Information System (INIS)

Oji, L.N.; Thompson, M.C.; Peterson, K.; May, C.; Kafka, T.M.

1998-01-01

This report describes results from a seven-day demonstration of the use of 3M Empore membrane filter loaded with ion exchange material (potassium cobalt hexacynoferrate (CoHex)) for cesium uptake from the R-Disassembly Basin at the Savannah River Site. The goal of the demonstration was to evaluate the ability of the Process Absorber Development unit (PADU), a water pre-filtration /CoHex configuration on a skid, to remove cesium from R-Disassembly Basin at a linear processing flow rate of 22.7 liters per minute (1,195.8 liters/minute/m 2 or 29.35 gallons/minute/ft 2 ). Over 210,000 liters (> 55,500 gallons) of R-Disassembly Basin water was processed through the PADU without a cesium breakthrough, that is, the effluent after treatment with CoHex, contained less than detectable amounts of radioactive cesium. Some of the observed advantages of the Empore membrane filter technology over conventional packed column ion exchange systems includes rapid flow rates without channeling effects, low volume secondary waste and fast extraction or rapid kinetics per unit of flow

Phosphorus mobilization in rewetted peat and sand at variable flow rate and redox regimes

DEFF Research Database (Denmark)

Kjærgaard, Charlotte; Heiberg, Lisa; Jensen, Henning S.

2012-01-01

the upward percolation of groundwater with variable O2 content and flow rate, we investigated the hydro-biogeochemical Fe and P dynamics in intact cores of a carbon rich peat and carbon poor sand. Percolation of deionized water with high, low or no O2 supply at 10 °C caused markedly different in situ redox...... rates from 7.6 to 11 mg P m−2 day−1. Organic or particulate P contributed to 40–45% of total P losses from the peat. In contrast, the high O2 supply during high flow rate kept the peat oxic and lowered TP release rates to 6.7 mg P m−2 day−1. The carbon poor sand demonstrated that this soil type...... regimes in the two soils during 21 or 67 days of continuous percolation at either 1 or 4 mm h−1. Anoxic conditions occurred in the peat soil at both low oxygen supply and anoxic infiltration, causing reductive Fe(III) dissolution with high Fe(II) and P effluent concentrations and total P (TP) release...

Impact Of Sodium Oxalate, Sodium Aluminosilicate, and Gibbsite/Boehmite on ARP Filter Performance

Energy Technology Data Exchange (ETDEWEB)

Poirier, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-11-01

The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). Recently, the low filter flux through the ARP of approximately 5 gallons per minute has limited the rate at which radioactive liquid waste can be treated. Salt Batch 6 had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. SRR requested SRNL to conduct bench-scale filter tests to evaluate whether sodium oxalate, sodium aluminosilicate, or aluminum solids (i.e., gibbsite and boehmite) could be the cause of excessive fouling of the crossflow or secondary filter at ARP. The authors conducted the tests by preparing slurries containing 6.6 M sodium Salt Batch 6 supernate, 2.5 g MST/L slurry, and varying concentrations of sodium oxalate, sodium aluminosilicate, and aluminum solids, processing the slurry through a bench-scale filter unit that contains a crossflow primary filter and a dead-end secondary filter, and measuring filter flux and transmembrane pressure as a function of time. Among the conclusions drwn from this work are the following: (1) All of the tests showed some evidence of fouling the secondary filter. This fouling could be from fine particles passing through the crossflow filter. (2) The sodium oxalate-containing feeds behaved differently from the sodium aluminosilicate- and gibbsite/boehmite-containing feeds.

Phosphorus removal from UASB reactor effluent by reactive media filtration.

Science.gov (United States)

Rodríguez-Gómez, Raúl; Renman, Gunno

2017-08-01

The phosphorus (P) and BOD7 removal performance of an upflow packed bed reactor (PBR) filled with two reactive filter media was studied over 50 weeks. The lower one-fifth of the reactor was filled with calcium-silicate-hydrate (Sorbulite®) and the upper four-fifth with calcium-silicate (Polonite®). A laboratory-scale upflow anaerobic sludge bed reactor (UASB) delivered wastewater to the PBR. A model was developed to describe the gradient in P concentration change in the reactor, based on reaction kinetics. The reaction terms were assumed to follow the Langmuir isotherm, based on the results obtained in a batch test. First, a comparison was made between experimental and simulated results. The capability of the model to forecast P removal capacity was then tested for three hypothetical cases: (i) reactor filled with Sorbulite and Polonite, (ii) reactor filled with only Sorbulite, and (iii) reactor filled with only Polonite. Finally, a sensitivity analysis was performed for the main parameters in the model. The average removal of P and BOD7 from the UASB effluent was 98% and 90%, respectively. The starting pH of the dual-medium effluent was 12.2 and decreased gradually over time to 11.1. The simulation both overestimated and underestimated mean measured P removal but was within the range of maximum and minimum measured values. The hypothetical cases revealed that most P was removed by Polonite due to calcium phosphate precipitation. The removal capacity of the two filter materials and their layer height in the reactor were the most sensitive parameters in the simulation.

Treatment of Radioactive Effluents at the Saclay Nuclear Research Centre

Energy Technology Data Exchange (ETDEWEB)

Wormser, Gerald [Atomic Energy Commission, Saclay (France)

1960-07-01

Investigations have also been made at Saclay to find out if the soil at the Centre could be used to receive SNRC effluents. The Saclay plateau is a sand plateau 75 m thick on a clay base (2). Its upper surface is covered by a heterogeneous layer of clay containing pieces of grindstone of varying sizes. The ion-exchange capacity of this soil is considerable, 25 meq/100 g. Low-activity waste could therefore be discharged into it, especially since the plateau has no lateral water outcrops of any size and underground water does not reappear for a long time. This method of disposal is still only experimental. It was tested with a solution of Sr{sup 90} and tritium having an activity equal to the permitted levels.

Removal of COD and TSS From Dye Solution Using Sand Filtration and Adsorption

Directory of Open Access Journals (Sweden)

Heny Juniar

2016-11-01

Full Text Available This research was conducted in order to obtain proper compositions and the standard condition for the simple filtration equipments and optimum operational conditions in adsorption column. The research was carried out by analyzing parameters COD and TSS. The result showed that the process was able to reduced parameters observed from filtration step until the process in adsorptions column. The optimum conditions for sand filter equipment were 10 cm sand height, at least 7 cm fibers, 3-4 cm gravel. In the adsorption column, the optimum conditions for green waste water were flow rate at 40 ml/min 60 min adsorptions time, and 60 cm bed height. While purple for waste water; 20 mL/min of flowrate, 60 min of adsorption time, and the 60 cm of bed height

Optimization of O3 as Pre-Treatment and Chemical Enhanced Backwashing in UF and MF Ceramic Membranes for the Treatment of Secondary Wastewater Effluent and Red Sea Water

KAUST Repository

Herrera, Catalina

2011-12-12

Ceramic membranes have proven to have many advantages over polymeric membranes. Some of these advantages are: resistance against extreme pH, higher permeate flux, less frequent chemical cleaning, excellent backwash efficiency and longer lifetime. Other main advantage is the use of strong chemical agent such as Ozone (O3), to perform membrane cleaning. Ozone has proven to be a good disinfection agent, deactivating bacteria and viruses. Ozone has high oxidation potential and high reactivity with natural organic matter (NOM). Several studies have shown that combining ozone to MF/UF systems could minimize membrane fouling and getting higher operational fluxes. This work focused on ozone – ceramic membrane filtration for treating wastewater effluent and seawater. Effects of ozone as a pre – treatment or chemical cleaning with ceramic membrane filtration were identified in terms of permeate flux and organic fouling. Ozonation tests were done by adjusting O3 dose with source water, monitoring flux decline and membrane fouling. Backwashing availability and membrane recovery rate were also analyzed. Two types of MF/UF ceramics membranes (AAO and TAMI) were used for this study. When ozone dosage was higher in the source water, membrane filtration improved in performance, resulting in a reduced flux decline. In secondary wastewater effluent, raw source water declined up to 77% of normalized flux, while with O3 as pre – treatment, source water at its higher O3 dose, flux decreased only 33% of normalized flux. For seawater, membrane performance increase from declining to 37% of its final normalized flux to 21%, when O3 as a pre – treatment was used. Membrane recovery rate also improved even with low O3 dose, as an example, with 8 mg/L irreversible fouling decreases from 58% with no ozone addition to 29% for secondary wastewater effluent treatment. For seawater treatment, irreversible fouling decreased from 37% with no ozone addition to 21% at 8 mg/L, proving ozone is a

Log analysis in the shallow oil sands of the San Joaquin Valley, California

International Nuclear Information System (INIS)

Vohs, J.B.

1976-01-01

Many fields in the San Joaquin Valley of California produce oil from a depth of 2,500 ft or less. During the period of primary production in these fields, evaluation of potential pay intervals from logs was restricted to examination of ES logs and correlation. With the introduction of secondary and tertiary recovery techniques the need for more and better answers, more quickly available, became apparent. However, several log-analysis problems had to be resolved. Formation evaluation using well logs was complicated by the shaliness of the sand intervals, the low and variable salinity of the formation waters, and the presence of low-pressure-gas (depleted) zones in many of the shallow sands. Solutions to these problems have required more modern logging programs and interpretation techniques. Logs available for the evaluation of these sands are the dual induction-laterolog, the compensated formation density log, the compensated neutron log, and the microlaterolog or proximity log. With this suite of logs it is possible to determine the shale content, porosity, saturation in the flushed zone, and water saturation of the sand, and to locate the low-pressure-gas sands and depleted zones. In cases where freshwater and oil are interlayered, it is possible to tell which sands contain oil and which contain only water. Because a quick interpretation is required, wellsite techniques are called for. These will be described

Study of Black Sand Particles from Sand Dunes in Badr, Saudi Arabia Using Electron Microscopy

Directory of Open Access Journals (Sweden)

Haider Abbas Khwaja

2015-08-01

Full Text Available Particulate air pollution is a health concern. This study determines the microscopic make-up of different varieties of sand particles collected at a sand dune site in Badr, Saudi Arabia in 2012. Three categories of sand were studied: black sand, white sand, and volcanic sand. The study used multiple high resolution electron microscopies to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of surface “coatings or contaminants” deposited or transported by the black sand particles. White sand was comprised of natural coarse particles linked to wind-blown releases from crustal surfaces, weathering of igneous/metamorphic rock sources, and volcanic activities. Black sand particles exhibited different morphologies and microstructures (surface roughness compared with the white sand and volcanic sand. Morphological Scanning Electron Microscopy (SEM and Laser Scanning Microscopy (LSM analyses revealed that the black sand contained fine and ultrafine particles (50 to 500 nm ranges and was strongly magnetic, indicating the mineral magnetite or elemental iron. Aqueous extracts of black sands were acidic (pH = 5.0. Fe, C, O, Ti, Si, V, and S dominated the composition of black sand. Results suggest that carbon and other contaminant fine particles were produced by fossil-fuel combustion and industrial emissions in heavily industrialized areas of Haifa and Yanbu, and transported as cloud condensation nuclei to Douf Mountain. The suite of techniques used in this study has yielded an in-depth characterization of sand particles. Such information will be needed in future environmental, toxicological, epidemiological, and source apportionment studies.

Field application of farmstead runoff to vegetated filter strips: surface and subsurface water quality assessment.

Science.gov (United States)

Larson, Rebecca A; Safferman, Steven I

2012-01-01

Farmstead runoff poses significant environmental impacts to ground and surface waters. Three vegetated filter strips were assessed for the treatment of dairy farmstead runoff at the soil surface and subsurface at 0.3- or 0. 46-m and 0. 76-m depths for numerous storm events. A medium-sized Michigan dairy was retrofitted with two filter strips on sandy loam soil and a third filter strip was implemented on a small Michigan dairy with sandy soil to collect and treat runoff from feed storage, manure storage, and other impervious farmstead areas. All filter strips were able to eliminate surface runoff via infiltration for all storm events over the duration of the study, eliminating pollutant contributions to surface water. Subsurface effluent was monitored to determine the contributing groundwater concentrations of numerous pollutants including chemical oxygen demand (COD), metals, and nitrates. Subsurface samples have an average reduction of COD concentrations of 20, 11, and 85% for the medium dairy Filter Strip 1 (FS1), medium dairy Filter Strip 2 (FS2), and the small Michigan dairy respectively, resulting in average subsurface concentrations of 355, 3960, and 718 mg L COD. Similar reductions were noted for ammonia and total Kjeldahl nitrogen (TKN) in the subsurface effluent. The small Michigan dairy was able to reduce the pollutant leachate concentrations of COD, TKN, and ammonia over a range of influent concentrations. Increased influent concentrations in the medium Michigan dairy filter strips resulted in an increase in COD, TKN, and ammonia concentrations in the leachate. Manganese was leached from the native soils at all filter strips as evidenced by the increase in manganese concentrations in the leachate. Nitrate concentrations were above standard drinking water limits (10 mg L), averaging subsurface concentrations of 11, 45, and 25 mg L NO-N for FS1, FS2, and the small Michigan dairy, respectively. Copyright © by the American Society of Agronomy, Crop Science

Secondary coolant purification system

International Nuclear Information System (INIS)

Stiteler, F.Z.; Donohue, J.P.

1978-01-01

The present invention combines the attributes of volatile chemical addition, continuous blowdown, and full flow condensate demineralization. During normal plant operation (defined as no primary to secondary leakage) condensate from the condenser is pumped through a full flow condensate demineralizer system by the condensate pumps. Volatile chemical additions are made. Dissolved and suspended solids are removed in the condensate polishers by ion exchange and/or filtration. At the same time a continuous blowdown of approximately 1 percent of the main steaming rate of the steam generators is maintained. Radiation detectors monitor the secondary coolant. If these monitors indicate no primary to secondary leakage, the blowdown is cooled and returned directly to the condensate pump discharge. If one of the radiation monitors should indicate a primary to secondary leak, when the temperature of the effluent exiting from the blowdown heat exchanger is compatible with the resin specifications of the ion exchangers, the bypass valve causes the blowdown flow to pass through the blowdown ion exchangers

Seabed Filter Feasibility Study of Om Almisk Island

KAUST Repository

Sesler, Kathryn

2012-06-01

Freshwater access has always been and is continuing to be a severe problem in desert coastal regions, despite the fact that they have an unlimited supply of easily accessible saline water. Water desalination plants are well established and heavily relied upon throughout the Middle East, Saudi Arabia in particular. However, water desalination tends to be a very expensive and energy intensive solution to the problem. The transition from using open water intake systems and all of the pretreatment processes that they require, to using seabed water filters as an intake, would potentially reduce the lifetime costs, energy consumption, and environmental impacts commonly associated with water desalination. This is because the filtration process that the seabed filter generates, serves as sufficient pretreatment for seawater as well as eliminating any risk of entrainment or impingement of marine organisms. The main objective of this research is to conduct a feasibility study on Om Almisk Island, an island off the coast of King Abdullah University of Science and Technology (KAUST), to determine if it would be a suitable location to construct a seabed water filter as a replacement for the current open water intake. The Om Almisk Island site was evaluated through collection of sand samples over a radial grid around Om Almisk Island and sample analysis using grain size distribution, porosity, and hydraulic conductivity. The lack of mud, high hydraulic conductivity, proximity to KAUST, and the shallow waters of the sandy apron surrounding Om Almisk Island make this an ideal location for a seabed water filter to be used as an intake and pretreatment for the KAUST desalination plant. This location also has low tide change and the presence of benthic macrofauna to create bioturbation in the sediments, which could inhibit the growth of a schmutzdecke. If this biological layer forms, it could drastically reduce the hydraulic conductivity of the system. Due to the high hydraulic

THE USE OF BIOREACTORS COUPLED WITH MEMBRANES FOR THE TREATMENT OF EFFLUENTS

Directory of Open Access Journals (Sweden)

Bergamasco R.

1997-01-01

Full Text Available The objectives of this paper are to verify the viability of operating a bioreactor coupled with a membrane, and to analyze the global mechanisms witch need to be considered in the bioreactional concept in the separation by membrane. In order to meet the proposed objectives, a culture with a synthetic substratum (ethanol was utilized. A mineral membrane with the following characteristics was used: a pore diameter of 0.2 m m, 19 channels of a 4 mm diameter, a width of 0.85 m, a filtering surface area of 0.2 m2, a pressure of 2 bar and a tangential velocity of 2 m/s. The experiments consisted of modifying the residence time of the substratum within the reactor. The following measurements were taken: chemical oxygen demand (COD, concentration of biomass and filtered flow. The results show a treated effluent of good quality, indicating that the time of hydraulic residence time influences the efficiency of the system and is influenced by the restriction of the filtered flow by a fast fouling of the membrane

Modeling the Performance of Biological Rapid Sand Filters Used to Remove Ammonium, Iron, and Manganese From Drinking Water

DEFF Research Database (Denmark)

Lee, Carson; Albrechtsen, Hans-Jørgen; Smets, Barth F.

activated carbon and are often used following ozonation to remove additional biodegradable organics created during ozonation. In Europe, biological filters are also used to remove ammonium and reduced forms of iron and manganese. These compounds can cause biological instability in the distribution system...... tracer, are performed during an operational cycle of a filter to examine how the filter flow changes with time. The data is used to validate a mathematical model that can both predict process performance and to gain an understanding of how dynamic conditions can influence filter performance....... The mathematical model developed is intended to assist in the design of new filters, set up of pilot plant studies, and as a tool to troubleshoot existing problems in full scale filters. Unlike previous models, the model developed accounts for the effects of particle/precipitate accumulation and its effects...

Post-Secondary Learning Priorities of Workers in an Oil Sands Camp in Northern Alberta

Science.gov (United States)

Fahy, Patrick J.; Steel, Nancy

2008-01-01

This paper reports results to date of a three-year project by Athabasca University, intended to determine the education and training needs and interests of employees in a work camp in northern Alberta's oil sands. (Future reports will address results of efforts to provide programming suiting the needs identified, and the uptake, satisfaction,…

CONCAWE effluent speciation project

Energy Technology Data Exchange (ETDEWEB)

Leonards, P.; Comber, M.; Forbes, S.; Whale, G.; Den Haan, K.

2010-09-15

In preparation for the implementation of the EU REACH regulation, a project was undertaken to transfer the high-resolution analytical method for determining hydrocarbon blocks in petroleum products by comprehensive two-dimensional gas chromatography (GCxGC) to a laboratory external to the petroleum industry (Institute for Environmental Studies (IVM) of the VU University of Amsterdam). The method was validated and used for the analysis of petroleum hydrocarbons extracted from refinery effluents. The report describes the technology transfer and the approaches used to demonstrate the successful transfer and application of the GCxGC methodology from analysing petroleum products to the quantitative determination of hydrocarbon blocks in refinery effluents. The report describes all the methods used for all the determinations on the effluent samples along with an overview of the results obtained which are presented in summary tables and graphs. These data have significantly improved CONCAWE's knowledge of what refineries emit in their effluents. A total of 111 Effluent Discharge Samples from 105 CONCAWE refineries in Europe were obtained in the period June 2008 to March 2009. These effluents were analysed for metals, standard effluent parameters (including COD, BOD), oil in water, BTEX and volatile organic compounds. The hydrocarbon speciation determinations and other hydrocarbon analyses are also reported. The individual refinery analytical results are included into this report, coded as per the CONCAWE system. These data will be, individually, communicated to companies and refineries. The report demonstrates that it is feasible to conduct a research programme to investigate the fate and effects of hydrocarbon blocks present in discharged refinery effluents.

Toxicity on aquatic organisms exposed to secondary effluent disinfected with chlorine, peracetic acid, ozone and UV radiation.

Science.gov (United States)

da Costa, Juliana Berninger; Rodgher, Suzelei; Daniel, Luiz Antonio; Espíndola, Evaldo Luiz Gaeta

2014-11-01

The toxic potential of four disinfectant agents (chlorine, ozone, peracetic acid and UV radiation), used in the disinfection of urban wastewater, was evaluated with respect to four aquatic organisms. Disinfection assays were carried out with wastewater from the city of Araraquara (São Paulo State, Brazil), and subsequently, toxicity bioassays were applied in order to verify possible adverse effects to the cladocerans (Ceriodaphnia silvestrii and Daphnia similis), midge larvae Chironomus xanthus and fish (Danio rerio). Under the experimental conditions tested, all the disinfectants were capable of producing harmful effects on the test organisms, except for C. xanthus. The toxicity of the effluent to C. silvestrii was observed to increase significantly as a result of disinfection using 2.5 mg L(-1) chlorine and 29.9 mg L(-1) ozone. Ozonation and chlorination significantly affected the survival of D. similis and D. rerio, causing mortality of 60 to 100 % in comparison to the non-disinfected effluent. In experiments with effluent treated with peracetic acid (PAA) and UV radiation, a statistically significant decrease in survival was only detected for D. rerio. This investigation suggested that the study of the ideal concentrations of disinfectants is a research need for ecologically safe options for the treatment of wastewater.

Effect of surfactant-coated iron oxide nanoparticles on the effluent water quality from a simulated sequencing batch reactor treating domestic wastewater

International Nuclear Information System (INIS)

Hwang, Sangchul; Martinez, Diana; Perez, Priscilla; Rinaldi, Carlos

2011-01-01

This study was conducted to evaluate the effect of commercially available engineered iron oxide nanoparticles coated with a surfactant (ENP Fe-surf ) on effluent water quality from a lab-scale sequencing batch reactor as a model secondary biological wastewater treatment. Results showed that ∼8.7% of ENP Fe-surf applied were present in the effluent stream. The stable presence of ENP Fe-surf was confirmed by analyzing the mean particle diameter and iron concentration in the effluent. Consequently, aqueous ENP Fe-surf deteriorated the effluent water quality at a statistically significant level (p Fe-surf would be introduced into environmental receptors through the treated effluent and could potentially impact them. - Highlights: → Surfactant-coated engineered iron oxide nanoparticles (ENP Fe-surf ) were assessed. → Effluent quality was analyzed from a sequencing batch reactor with ENP Fe-surf . → ∼8.7% of ENP Fe-surf applied was present in the effluent. → ENP Fe-surf significantly (p Fe-surf will be introduced into environmental receptors. - Stable presence of surfactant-coated engineered iron oxides nanoparticles deteriorated the effluent water quality at a statistically significant level (p < 0.05).

New generation expandable sand screens

OpenAIRE

Syltøy, Christer

2014-01-01

Master's thesis in Petroleum engineering This thesis aims to give a general insight into sand control and various sorts of sand control measures and applications of sand control tools. Special focus will be given to expandable sand screens – a technology which came about in the late 1990’s through the use of flexible, expandable tubulars as base pipe in sand screens. More specifically Darcy’s Hydraulic Endurance Screens, a compliant sand screen system using hydraulic activation, and the fu...

Performance of Elaeis Guineensis Leaves Compost in Filter Media for Stormwater Treament Through Column Study

Science.gov (United States)

Takaijudin, H.; Ghani, A. A.; Zakaria, N. A.; Tze, L. L.

2016-07-01

Compost based materials arv e widely used in filter media for improving soil capability and plant growth. The aim of this paper is to evaluate different types of compost materials used in engineered soil media through soil column investigation. Three (3) column, namely C1 (control), C2 and C3 had different types compost (10%) which were, commercial compost namely PEATGRO, Compost A and Compost B were prepared with 60% medium sand and 30% of topsoil. The diluted stormwater runoff was flushed to the columns and it was run for six (6) hour experiment. The influent and effluent samples were collected and tested for Water Quality Index (WQI) parameters. The results deduced that C3 with Elaeis Guineensis leaves compost (Compost B) achieved 90.45 (Class II) better than control condition which accomplished 84 (Class II) based on WQI Classification. C3 with Compost A (African Mahogany Leaves Compost) obtained only 59.39 (Class III). C3 with the composition of Compost B effectively removed most pollutants, including Chemical Oxygen Demand (COD, Ammoniacal Nitrogen (NH3-N), were reduced by 89±4% and 96.6±0.9%, respectively. The result concluded that Elaeis Guineensis leaves compost is recommended to be used as part of engineered soil media due to its capabilities in eliminating stormwater pollutants.