Biomass heating at East Surrey Hospital: technical evaluation

Energy Technology Data Exchange (ETDEWEB)

Landen, R; Rippengal, R

2000-07-01

This report provides the results of a detailed evaluation of the proposed biomass heating installation at East Surrey Hospital. It is intended to allow the Trust to make a decision on whether to proceed further with the scheme and, if so, on what basis. Specific areas assessed and reported on include: existing services provision for heating and cooling; technical aspects of the proposed biomass scheme; commercial aspects of the proposed biomass scheme. (author)

Port Graham Community Building Biomass Heating Design Project

Energy Technology Data Exchange (ETDEWEB)

Norman, Patrick [Port Graham Village Corporation, Anchorage, AK (United States); Sink, Charles [Chugachmiut, Anchorage, Alaska (United States)

2015-04-30

Native Village of Port Graham completed preconstruction activities to prepare for construction and operations of a cord wood biomass heating system to five or more community buildings in Port Graham, Alaska. Project Description Native Village of Port Graham (NVPG) completed preconstruction activities that pave the way towards reduced local energy costs through the construction and operations of a cord wood biomass heating system. NVPG plans include installation of a GARN WHS 3200 Boiler that uses cord wood as fuel source. Implementation of the 700,000 Btu per hour output biomass community building heat utility would heat 5-community buildings in Port Graham, Alaska. Heating system is estimated to displace 85% of the heating fuel oil or 5365 gallons of fuel on an annual basis with an estimated peak output of 600,000 Btu per hour. Estimated savings is $15,112.00 per year. The construction cost estimate made to install the new biomass boiler system is estimated $251,693.47 with an additional Boiler Building expansion cost estimated at $97,828.40. Total installed cost is estimated $349,521.87. The WHS 3200 Boiler would be placed inside a new structure at the old community Water Plant Building site that is controlled by NVPG. Design of the new biomass heat plant and hot water loop system was completed by Richmond Engineering, NVPG contractor for the project. A hot water heat loop system running off the boiler is designed to be placed underground on lands controlled by NVPG and stubbed to feed hot water to existing base board heating system in the following community buildings: 1. Anesia Anahonak Moonin Health and Dental Clinic 2. Native Village of Port Graham offices 3. Port Graham Public Safety Building/Fire Department 4. Port Graham Corporation Office Building which also houses the Port Graham Museum and Head Start Center 5. North Pacific Rim Housing Authority Workshop/Old Fire Hall Existing community buildings fuel oil heating systems are to be retro-fitted to

Heat storage in forest biomass significantly improves energy balance closure particularly during stable conditions

Science.gov (United States)

Lindroth, A.; Mölder, M.; Lagergren, F.

2009-08-01

Temperature measurements in trunks and branches in a mature ca. 100 years-old mixed pine and spruce forest in central Sweden were used to estimate the heat storage in the tree biomass. The estimated heat flux in the sample trees and data on biomass distributions were used to scale up to stand level biomass heat fluxes. The rate of change of sensible and latent heat storage in the air layer below the level of the flux measurements was estimated from air temperature and humidity profile measurements and soil heat flux was estimated from heat flux plates and soil temperature measurements. The fluxes of sensible and latent heat from the forest were measured with an eddy covariance system in a tower. The analysis was made for a two-month period in summer of 1995. The tree biomass heat flux was the largest of the estimated storage components and varied between 40 and -35 W m-2 on summer days with nice weather. Averaged over two months the diurnal maximum of total heat storage was 45 W m-2 and the minimum was -35 W m-2. The soil heat flux and the sensible heat storage in air were out of phase with the biomass flux and they reached maximum values that were about 75% of the maximum of the tree biomass heat storage. The energy balance closure improved significantly when the total heat storage was added to the turbulent fluxes. The slope of a regression line with sum of fluxes and storage as independent and net radiation as dependent variable, increased from 0.86 to 0.95 for half-hourly data and the scatter was also reduced. The most significant finding was, however, that during nights with strongly stable conditions when the sensible heat flux dropped to nearly zero, the total storage matched the net radiation nearly perfectly. Another interesting result was that the mean energy imbalance started to increase when the Richardson number became more negative than ca. -0.1. In fact, the largest energy deficit occurred at maximum instability. Our conclusion is that eddy

Market Potential for Residential Biomass Heating Equipment: Stochastic and Econometric Assessments

OpenAIRE

Adee Athiyaman

2015-01-01

This paper provides estimates of market potential for biomass-residential-heating equipment in the US: that is, the greatest amount of biomass-residential-heating equipment that can be sold by the industry. The author's analysis is limited to biomass equipment used most to heat the housing unit. Assuming that households equipped with 10+ year old primary heating devices will replace rather than repair the devices he predicts that approximately 1.4 million units of residential home heating equ...

Solar-assisted biomass-district heating: projects in Austria and operational data; Solarunterstuetzte Biomasse-Fernwaermeversorgung: Projekte in Oesterreich und Betriebsdaten

Energy Technology Data Exchange (ETDEWEB)

Faninger, G. [Institut fuer Interdisziplinaere Forschung und Fortbildung der Universitaeten Klagenfurt, Innsbruck und Wien (IFF), Klagenfurt (Austria)

1998-12-31

In recent years small-volume biomass district heating systems (district heat grids) have attracted increasing interest in Austria. By the end of 1997 some 359 biomass-district heating systems with an overall capacity of approximately 483 MW were in operation. If a biomass-district heating plant and a solar plant are combined the solar plant can supply most of the heat required outside the heating season. At present Austria runs 12 solar-assisted biomass-district heating grids with collector areas between 225 square metres and 1,250 square metres. In order to run these biomass-district heating systems in an economically and technically efficient way it is necessary to assure high quality in terms of planning, construction and operation. A list of criteria is set up on the basis of first operational data in order to evaluate energy efficiency and economic performance. These criteria should be applied in order to ensure that energy, environment and economy are equally considered in the planning and construction of solar-assisted biomass-district heating plants. They should also be helpful for the approval procedures of projects. (orig.) [Deutsch] Kleinraeumige Biomasse-Fernwaermeanlagen (Nahwaermenetze) fanden in den letzten Jahren zunehmendes Interesse in Oesterreich. So waren Ende 1997 insgesamt 359 Biomasse-Fernwaermeanlagen mit einer installierten Gesamtleistung von etwa 483 MW in Betrieb. Die Kombination einer Biomasse-Fernwaermeanlage mit einer Solaranlage bringt den Vorteil, dass die Waermebereitstellung ausserhalb der Heizsaison zu einem hohen Anteil ueber die Solaranlage vorgenommen werden kann. Derzeit werden in Oesterreich 12 solarunterstuetzte Biomasse-Nahwaermenetze mit Kollektorflaechen von 225 m{sup 2} bis 1.250 m{sup 2} betrieben. Um einen moeglichst effizienten und damit auch wirtschaftlichen Betrieb von solarunterstuetzten Biomasse-Fernwaermeanlagen zu gewaehrleisten, werden hohe Anforderungen an Planung, Ausfuehrung und Betrieb gestellt. Auf der

Biomass gasification to heat, electricity and biofuels. HighBio project publication

Energy Technology Data Exchange (ETDEWEB)

Lassi, U.; Wikman, B. (eds.)

2011-07-01

Renewable energy and the use of biomass in energy production promotes sustainable development and decreases the use of fossil fuels. Biomass, e.g. wood chips can be used in the production of heat and electricity, as well as being used as a biofuel component and novel product for the chemical industry. Efficient utilisation of biomass requires a high level of knowledge and the development of new processes to create a new way of thinking. In this process, international co-operation plays a significant role. The aim of the HighBio project was to produce new information on biomass gasification and the utilisation opportunities of product gas in biofuel and biochemicals production. The project was also aimed at studying utilisation properties of biogasification ashes in distributed energy production. Small-scaled CHP plants can be used for simultaneous heat and power production by gasifying wood chips and by burning energy intensive product gas. Compared with thermal combustion, particulate emissions from gasification are lower, which also contributes to the EU's ever tightening emission legislation. Several small and middle scale companies in the Northern part of Finland and Sweden have worked with biomass gasification, and during the project, the birth of new ones has been seen. In this development stage, researchers of the HighBio project have also been strongly involved. Increased use of renewable energy opens up new possibilities for entrepreneurship and the birth of new companies, especially in rural areas. In order to enable these opportunities, we need research data from the universities, novel innovations, and especially their successful commercialisation. The HighBio project has also contributed to tackling those challenges by arranging research seminars and meetings to companies and other interest groups, as well as by establishing research activities and collaborations. Regional collaboration combined with national and international research networks

White Pine Co. Public School System Biomass Conversion Heating Project

Energy Technology Data Exchange (ETDEWEB)

Paul Johnson

2005-11-01

The White Pine County School District and the Nevada Division of Forestry agreed to develop a pilot project for Nevada using wood chips to heat the David E. Norman Elementary School in Ely, Nevada. Consideration of the project was triggered by a ''Fuels for Schools'' grant that was brought to the attention of the School District. The biomass project that was part of a district-wide energy retrofit, called for the installation of a biomass heating system for the school, while the current fuel oil system remained as back-up. Woody biomass from forest fuel reduction programs will be the main source of fuel. The heating system as planned and completed consists of a biomass steam boiler, storage facility, and an area for unloading and handling equipment necessary to deliver and load fuel. This was the first project of it's kind in Nevada. The purpose of the DOE funded project was to accomplish the following goals: (1) Fuel Efficiency: Purchase and install a fuel efficient biomass heating system. (2) Demonstration Project: Demonstrate the project and gather data to assist with further research and development of biomass technology; and (3) Education: Educate the White Pine community and others about biomass and other non-fossil fuels.

Logistics, Costs, and GHG Impacts of Utility Scale Cofiring with 20% Biomass

Energy Technology Data Exchange (ETDEWEB)

Boardman, Richard D.; Cafferty, Kara G.; Nichol, Corrie; Searcy, Erin M.; Westover, Tyler; Wood, Richard; Bearden, Mark D.; Cabe, James E.; Drennan, Corinne; Jones, Susanne B.; Male, Jonathan L.; Muntean, George G.; Snowden-Swan, Lesley J.; Widder, Sarah H.

2014-07-22

This report presents the results of an evaluation of utility-scale biomass cofiring in large pulverized coal power plants. The purpose of this evaluation is to assess the cost and greenhouse gas reduction benefits of substituting relatively high volumes of biomass in coal. Two scenarios for cofiring up to 20% biomass with coal (on a lower heating value basis) are presented; (1) woody biomass in central Alabama where Southern Pine is currently produced for the wood products and paper industries, and (2) purpose-grown switchgrass in the Ohio River Valley. These examples are representative of regions where renewable biomass growth rates are high in correspondence with major U.S. heartland power production. While these scenarios may provide a realistic reference for comparing the relative benefits of using a high volume of biomass for power production, this evaluation is not intended to be an analysis of policies concerning renewable portfolio standards or the optimal use of biomass for energy production in the U.S.

Biomass universal district heating systems

Science.gov (United States)

Soltero, Victor Manuel; Rodríguez-Artacho, Salvador; Velázquez, Ramón; Chacartegui, Ricardo

2017-11-01

In mild climate regions Directive 27/2012 EU application for developing sustainable district heating networks in consolidated urban nucleus is a challenge. In Spain most of the municipalities above 5,000 inhabitants have a reliable natural gas network and individual heating systems at homes. In this work a new heating network paradigm is proposed, the biomass universal heating network in rural areas. This model involves all the economic, legal and technical aspects and interactions between the different agents of the systems: provider company, individual and collective end-users and local and regional administration. The continental region in Spain has 588 municipalities with a population above 1,500 inhabitants close to forest biomass with renewable use. In many of these cases the regulation identifies the ownership of the forest resources use. The universal heating networks are a great opportunity for energy saving of 2,000 GWh, avoiding 2.7 million tons of CO2 emissions and with a global annual savings for end users of 61.8 million of euros. The presented model is easily extrapolated to other small municipalities in Europe. The real application of the model is presented for three municipalities in different locations of Spain where Universal Heating Networks are under development. The analysis show the interest of the integrated model for the three cases with different structural agents and relationships between them. The use of sustainable forest resources, extracted and managed by local companies, strengths circular economy in the region with a potential global economic impact above 200 M€.

Successful scaling-up of self-sustained pyrolysis of oil palm biomass under pool-type reactor.

Science.gov (United States)

Idris, Juferi; Shirai, Yoshihito; Andou, Yoshito; Mohd Ali, Ahmad Amiruddin; Othman, Mohd Ridzuan; Ibrahim, Izzudin; Yamamoto, Akio; Yasuda, Nobuhiko; Hassan, Mohd Ali

2016-02-01

An appropriate technology for waste utilisation, especially for a large amount of abundant pressed-shredded oil palm empty fruit bunch (OFEFB), is important for the oil palm industry. Self-sustained pyrolysis, whereby oil palm biomass was combusted by itself to provide the heat for pyrolysis without an electrical heater, is more preferable owing to its simplicity, ease of operation and low energy requirement. In this study, biochar production under self-sustained pyrolysis of oil palm biomass in the form of oil palm empty fruit bunch was tested in a 3-t large-scale pool-type reactor. During the pyrolysis process, the biomass was loaded layer by layer when the smoke appeared on the top, to minimise the entrance of oxygen. This method had significantly increased the yield of biochar. In our previous report, we have tested on a 30-kg pilot-scale capacity under self-sustained pyrolysis and found that the higher heating value (HHV) obtained was 22.6-24.7 MJ kg(-1) with a 23.5%-25.0% yield. In this scaled-up study, a 3-t large-scale procedure produced HHV of 22.0-24.3 MJ kg(-1) with a 30%-34% yield based on a wet-weight basis. The maximum self-sustained pyrolysis temperature for the large-scale procedure can reach between 600 °C and 700 °C. We concluded that large-scale biochar production under self-sustained pyrolysis was successfully conducted owing to the comparable biochar produced, compared with medium-scale and other studies with an electrical heating element, making it an appropriate technology for waste utilisation, particularly for the oil palm industry. © The Author(s) 2015.

Catalytically supported reduction of emissions from small-scale biomass furnace systems

International Nuclear Information System (INIS)

Hartmann, Ingo; Lenz, Volker; Schenker, Marian; Thiel, Christian; Kraus, Markus; Matthes, Mirjam; Roland, Ulf; Bindig, Rene; Einicke, Wolf-Dietrich

2011-01-01

The increased use of solid biomass in small combustion for generating heat from renewable energy sources is unfortunately associated with increased emissions of airborne pollutants. The reduction is possible on the one hand by the use of high-quality modern furnaces to the latest state of the art. On the other hand, several promising approaches method for retrofitting small-scale furnaces are currently being developed that will allow an effective emission reduction by the subsequent treatment of the exhaust gas. The overview of current available emission control technologies for small-scale biomass combustion plants shows that there is still considerable need for research on the sustainable production of heat from solid biofuels. The amendment to the 1st BImSchV provides a necessary drastic reduction of discharged pollutants from small-scale biomass furnaces. When using the fuel wood in modern central heating boilers the required limits can be met at full load. However, dynamic load changes can cause brief dramatic emission increases even with wood central heating boilers. Firebox and control optimization must contribute in the future to a further reduction of emissions. The typical simple single-room fireplaces like hand-fed wood stoves are suitable under type test conditions to comply the limit values. By contrast, in practical operation, the harmful gas emissions be exceeded without secondary measures normally. The performed experimental investigations show that a reduction of both CO and of organic compounds by catalytic combustion is possible. In addition to developing specially adapted catalysts, it is necessary to provide additional dust separation by combined processes, since conventional catalysts are not suitable for deposition and retention of particulate matter or would lose their activity due to dust accumulation on the active surface, when the catalyst would act as a filter at the same time. To enable sufficiently high reaction temperatures and thus a

Biomass gasification for CHP with dry gas cleaning and regenerative heat recovery

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-05-01

Small scale CHP plants based on biomass gasification technologies are generally expensive and not very efficient due to gas quality problems which increase operation and maintenance cost as well as breakdown. To overcome this situation the team has developed, integrated and tested a complete biomass gasification combine heat and power prototype plant of 250 kWth equipped with a specifically developed dry gas cleaning and heat recovery system. The dry gas cleaning device is a simple dry gas regenerative heat exchanger where tars are stopped by condensation but working at a temperature above due point in order to avoid water condensation. Two types of heat particles separation devices have been tested in parallel multi-cyclone and ceramic filters. After several month spent on modelling design, construction and optimisation, a full test campaign of 400 hours continuous monitoring has been done where all working parameters has been monitored and gas cleaning device performances has been assessed. Results have shown: Inappropriateness of the ceramic filters for the small scale unit due to operation cost and too high sensibility of the filters to the operation conditions fluctuating in a wide range, despite a very high particle separation efficiency 99 %; Rather good efficiency of the multi-cyclone 72% but not sufficient for engine safety. Additional conventional filters where necessary for the finest part; Inappropriateness of the dry gas heat exchanger device for tar removal partly due to a low tar content of the syngas generated, below 100 mg/Nm{sup 3} , but also due to their composition which would have imposed, to be really efficient, a theoretical condensing temperature of 89 C below the water condensation temperature. These results have been confirmed by laboratory tests and modelling. However the tar cracking phase have shown very interesting results and proved the feasibility of thermal cracking with full cleaning of the heat exchanger without further mechanical

Biomass Supply Planning for Combined Heat and Power Plants using Stochastic Programming

DEFF Research Database (Denmark)

Guericke, Daniela; Blanco, Ignacio; Morales González, Juan Miguel

method using stochastic optimization to support the biomass supply planning for combined heat and power plants. Our two-phase approach combines mid-term decisions about biomass supply contracts with the short-term decisions regarding the optimal market participation of the producer to ensure......During the last years, the consumption of biomass to produce power and heat has increased due to the new carbon neutral policies. Nowadays, many district heating systems operate their combined heat and power (CHP) plants using different types of biomass instead of fossil fuel, especially to produce......, and heat demand and electricity prices vary drastically during the planning period. Furthermore, the optimal operation of combined heat and power plants has to consider the existing synergies between the power and heating systems while always fulfilling the heat demand of the system. We propose a solution...

Studying the melting behavior of coal, biomass, and coal/biomass ash using viscosity and heated stage XRD data

DEFF Research Database (Denmark)

Arvelakis, Stelios; Folkedahl, B.; Dam-Johansen, Kim

2006-01-01

by the cocombustion tests appeared to be somewhat different compared to that of the laboratory-prepared ash samples. The heated stage XRD data provide useful information regarding the reactions among the various ash compounds and the phase transformations during the heating and cooling of the ash samples and helped...... a high-temperature rotational viscometer and a hot stage XRD. The produced data were used to calculate the operating temperature of a pilot-scale entrained flow reactor during the cocombustion of biomass/ coal samples in order to ensure the slag flow and to avoid corrosion of the walls due to liquid slag...

Greenhouse gas emissions of Dutch biomass. Quantification of greenhouse gases emission of Dutch biomass for electricity and heat

International Nuclear Information System (INIS)

Koop, K.; Yildiz, I.

2010-09-01

The greenhouse gas emissions of all available flows of the biomass chain have been established. This report has the following aims: (1) to establish the greenhouse gas emission of Dutch biomass available for generating electricity and heat; (2) to obtain insight in the opportunities and threats for using the potential of the biomass chains that have the highest potential to reduce greenhouse gas emissions. This report can be seen as a supplement to the report 'Availability of Dutch biomass for electricity and heat in 2020' (2009) [nl

Effects of the distribution density of a biomass combined heat and power plant network on heat utilisation efficiency in village-town systems.

Science.gov (United States)

Zhang, Yifei; Kang, Jian

2017-11-01

The building of biomass combined heat and power (CHP) plants is an effective means of developing biomass energy because they can satisfy demands for winter heating and electricity consumption. The purpose of this study was to analyse the effect of the distribution density of a biomass CHP plant network on heat utilisation efficiency in a village-town system. The distribution density is determined based on the heat transmission threshold, and the heat utilisation efficiency is determined based on the heat demand distribution, heat output efficiency, and heat transmission loss. The objective of this study was to ascertain the optimal value for the heat transmission threshold using a multi-scheme comparison based on an analysis of these factors. To this end, a model of a biomass CHP plant network was built using geographic information system tools to simulate and generate three planning schemes with different heat transmission thresholds (6, 8, and 10 km) according to the heat demand distribution. The heat utilisation efficiencies of these planning schemes were then compared by calculating the gross power, heat output efficiency, and heat transmission loss of the biomass CHP plant for each scenario. This multi-scheme comparison yielded the following results: when the heat transmission threshold was low, the distribution density of the biomass CHP plant network was high and the biomass CHP plants tended to be relatively small. In contrast, when the heat transmission threshold was high, the distribution density of the network was low and the biomass CHP plants tended to be relatively large. When the heat transmission threshold was 8 km, the distribution density of the biomass CHP plant network was optimised for efficient heat utilisation. To promote the development of renewable energy sources, a planning scheme for a biomass CHP plant network that maximises heat utilisation efficiency can be obtained using the optimal heat transmission threshold and the nonlinearity

Effects of increased small-scale biomass combustion on local air quality - A theoretical dispersion modelling study

International Nuclear Information System (INIS)

Boman, C.

1997-01-01

The decided phasing out of nuclear power and the goal of reducing CO 2 emissions from fossil fuels causes a substantial estimated increase in the use of biomass fuels for energy production. Thus, a significant shift from small scale heating generated by electricity or fuel oil to biomass fuels is desirable. If a drastic deterioration of the local air quality is to be avoided, a reduction of today's emission limits is necessary. The objective of this report was therefore to describe the use of biomass fuels and small scale pellet fuel combustion, to make a theoretical study of the effects of increased pellets heating on the air quality in a residential area, and to discuss necessary emission limits for small biomass fuel plants. The general description is based on literature studies. In the theoretical study, several different dispersion model calculations were performed using the computer program Dispersion 1.1.0. The contents of tar and total hydrocarbons (THC) in the air were calculated for different scenarios with conversion from electricity to pellets and with different pellet plant performance. A sensitivity analysis was performed with additional variables and dispersion calculations according to an underlying statistical experimental design. The modeling and design computer program MODDE was used to facilitate design, evaluation and illustration of the calculated results. The results show that a substantial increase in the use of small scale pellets heating with worst calculated plant performance, will lead to a drastic increase of the content of hydrocarbons in the air. Thus, with best available performance, the content only increases marginally. Conversion from electricity to pellets, plant performance and time of year were the most influential variables. Also conversion from wood to pellets showed a significant effect, despite the small number of wood heated houses within the studied area. If a significant deterioration of the air quality is to be avoided

Biomass equipments. The wood-fueled heating plants; Materiels pour la biomasse. Les chaudieres bois

Energy Technology Data Exchange (ETDEWEB)

Chieze, B. [SA Compte R, 63 - Arlanc (France)

1997-12-31

This paper analyzes the consequences of the classification of biomass fuels in the French 2910 by-law on the classification of biomass-fueled combustion installations. Biomass fuels used in such installations must be only wood wastes without any treatment or coating. The design of biomass combustion systems must follow several specifications relative to the fueling system, the combustion chamber, the heat exchanger and the treatment of exhaust gases. Other technical solutions must be studied for other type of wood wastes in order to respect the environmental pollution laws. (J.S.)

Air emissions of small-scale (< 10 MW) biomass boilers. Review of three field tests

International Nuclear Information System (INIS)

Autret, E.

2011-01-01

Objectives of greenhouse gases emission reduction, which encourages bio-energy development for heat purposes, are compatible with air-quality policies if the concept of clean biomass combustion is applied. This paper presents actual emission levels of atmospheric pollutants of small-scale ( 2 , NO x , fine particulate matters, metallic compounds. Installation design (power, flue-gas cleaning techno logy) also has a major impact on organic pollutants and fine particulate matter emissions. A large majority of boilers have very low emission levels. Guidelines are finally stated to keep on promoting small-scale biomass boilers in order to be air-quality compatible and efficient to fight climate change. (author)

Rural electrification in Malaysia via small scale biomass gasifier

International Nuclear Information System (INIS)

Zainal Alimuddin Zainal Alauddin

2000-01-01

It is the government of Malaysia's vision to see that the rural community is not left behind in its endeavour to be an industrialised nation in the year 2020. The standard of living in the rural areas is very far different from that in the urban areas. To obtain equality the standard of living of the rural folks need to be ungraded. This is done largely by electrification. Electricity has been in the past the catalyst for development and raising the standard of living of the poor. Electricity supplied by the nation's electricity company might not reach all remote areas and therefore there must be a means to provide alternative electrical supply to these places. Present method employ the use of diesel generator sets to provide electricity. The availability of biomass source of supply in the rural areas could be effectively exploited to provide alternative source of energy via a gasification system to run a reciprocating engine coupled to a generator to generated electricity. A small-scale biomass gasification generator set in the range of 2-5 kW is suitable to provide electrical supply to a typical house in the rural area. The present use of biomass source of energy is in its utilisation to provide source of heat for cooking. Several tests have been conducted and the performance is very good. Alternatively another medium scale system generating about 50-20O kW would be suitable for a typical village having about 50 houses. A small-scale system has been developed in USM to provide 5 kW of electrical power. The system used a petrol engine and produces an overall efficiency of 7% with a specific consumption of about 3 kg/kWh. The biomass material used is wood. However for application in the rural areas the biomass material will depend on the type available. A further 50 kW system is being develop in USM. (Author)

Biomass gasification in district heating systems - The effect of economic energy policies

International Nuclear Information System (INIS)

Wetterlund, Elisabeth; Soederstroem, Mats

2010-01-01

Biomass gasification is considered a key technology in reaching targets for renewable energy and CO 2 emissions reduction. This study evaluates policy instruments affecting the profitability of biomass gasification applications integrated in a Swedish district heating (DH) system for the medium-term future (around year 2025). Two polygeneration applications based on gasification technology are considered in this paper: (1) a biorefinery plant co-producing synthetic natural gas (SNG) and district heat; (2) a combined heat and power (CHP) plant using integrated gasification combined cycle technology. Using an optimisation model we identify the levels of policy support, here assumed to be in the form of tradable certificates, required to make biofuel production competitive to biomass based electricity generation under various energy market conditions. Similarly, the tradable green electricity certificate levels necessary to make gasification based electricity generation competitive to conventional steam cycle technology, are identified. The results show that in order for investment in the SNG biorefinery to be competitive to investment in electricity production in the DH system, biofuel certificates in the range of 24-42 EUR/MWh are needed. Electricity certificates are not a prerequisite for investment in gasification based CHP to be competitive to investment in conventional steam cycle CHP, given sufficiently high electricity prices. While the required biofuel policy support is relatively insensitive to variations in capital cost, the required electricity certificates show high sensitivity to variations in investment costs. It is concluded that the large capital commitment and strong dependency on policy instruments makes it necessary that DH suppliers believe in the long-sightedness of future support policies, in order for investments in large-scale biomass gasification in DH systems to be realised.

Biomass combustion gas turbine CHP

Energy Technology Data Exchange (ETDEWEB)

Pritchard, D.

2002-07-01

This report summarises the results of a project to develop a small scale biomass combustor generating system using a biomass combustor and a micro-gas turbine indirectly fired via a high temperature heat exchanger. Details are given of the specification of commercially available micro-turbines, the manufacture of a biomass converter, the development of a mathematical model to predict the compatibility of the combustor and the heat exchanger with various compressors and turbines, and the utilisation of waste heat for the turbine exhaust.

Technoeconomic analysis of a biomass based district heating system

International Nuclear Information System (INIS)

Zhang, H.; Ugursal, V.I.; Fung, A.

2005-01-01

This paper discussed a proposed biomass-based district heating system to be built for the Pictou Landing First Nation Community in Nova Scotia. The community centre consists of 6 buildings and a connecting arcade. The methodology used to size and design heating, ventilating and air conditioning (HVAC) systems, as well as biomass district energy systems (DES) were discussed. Annual energy requirements and biomass fuel consumption predictions were presented, along with cost estimates. A comparative assessment of the system with that of a conventional oil fired system was also conducted. It was suggested that the design and analysis methodology could be used for any similar application. The buildings were modelled and simulated using the Hourly Analysis Program (HAP), a detailed 2-in-1 software program which can be used both for HVAC system sizing and building energy consumption estimation. A techno-economics analysis was conducted to justify the viability of the biomass combustion system. Heating load calculations were performed assuming that the thermostat was set constantly at 22 degrees C. Community centre space heating loads due to individual envelope components for 3 different scenarios were summarized, as the design architecture for the buildings was not yet finalized. It was suggested that efforts should be made to ensure air-tightness and insulation levels of the interior arcade glass wall. A hydronic distribution system with baseboard space heating units was selected, comprising of a woodchip boiler, hot water distribution system, convective heating units and control systems. The community has its own logging operation which will provide the wood fuel required by the proposed system. An outline of the annual allowable harvest covered by the Pictou Landing Forestry Management Plan was presented, with details of proposed wood-chippers for the creation of biomass. It was concluded that the woodchip combustion system is economically preferable to the

Modelling of heat transfer during torrefaction of large lignocellulosic biomass

Science.gov (United States)

Regmi, Bharat; Arku, Precious; Tasnim, Syeda Humaira; Mahmud, Shohel; Dutta, Animesh

2018-07-01

Preparation of feedstock is a major energy intensive process for the thermochemical conversion of biomass into fuel. By eliminating the need to grind biomass prior to the torrefaction process, there would be a potential gain in the energy requirements as the entire step would be eliminated. In regards to a commercialization of torrefaction technology, this study has examined heat transfer inside large cylindrical biomass both numerically and experimentally during torrefaction. A numerical axis-symmetrical 2-D model for heat transfer during torrefaction at 270°C for 1 h was created in COMSOL Multiphysics 5.1 considering heat generation evaluated from the experiment. The model analyzed the temperature distribution within the core and on the surface of biomass during torrefaction for various sizes. The model results showed similarities with experimental results. The effect of L/D ratio on temperature distribution within biomass was observed by varying length and diameter and compared with experiments in literature to find out an optimal range of cylindrical biomass size suitable for torrefaction. The research demonstrated that a cylindrical biomass sample of 50 mm length with L/D ratio of 2 can be torrefied with a core-surface temperature difference of less than 30 °C. The research also demonstrated that sample length has a negligible effect on core-surface temperature difference during torrefaction when the diameter is fixed at 25 mm. This information will help to design a torrefaction processing system and develop a value chain for biomass supply without using an energy-intensive grinding process.

Modelling of heat transfer during torrefaction of large lignocellulosic biomass

Science.gov (United States)

Regmi, Bharat; Arku, Precious; Tasnim, Syeda Humaira; Mahmud, Shohel; Dutta, Animesh

2018-02-01

Preparation of feedstock is a major energy intensive process for the thermochemical conversion of biomass into fuel. By eliminating the need to grind biomass prior to the torrefaction process, there would be a potential gain in the energy requirements as the entire step would be eliminated. In regards to a commercialization of torrefaction technology, this study has examined heat transfer inside large cylindrical biomass both numerically and experimentally during torrefaction. A numerical axis-symmetrical 2-D model for heat transfer during torrefaction at 270°C for 1 h was created in COMSOL Multiphysics 5.1 considering heat generation evaluated from the experiment. The model analyzed the temperature distribution within the core and on the surface of biomass during torrefaction for various sizes. The model results showed similarities with experimental results. The effect of L/D ratio on temperature distribution within biomass was observed by varying length and diameter and compared with experiments in literature to find out an optimal range of cylindrical biomass size suitable for torrefaction. The research demonstrated that a cylindrical biomass sample of 50 mm length with L/D ratio of 2 can be torrefied with a core-surface temperature difference of less than 30 °C. The research also demonstrated that sample length has a negligible effect on core-surface temperature difference during torrefaction when the diameter is fixed at 25 mm. This information will help to design a torrefaction processing system and develop a value chain for biomass supply without using an energy-intensive grinding process.

Fort Carson Building 1860 Biomass Heating Analysis Report

Energy Technology Data Exchange (ETDEWEB)

Hunsberger, Randolph [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tomberlin, Gregg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gaul, Chris [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-09-01

As part of the Army Net-Zero Energy Installation program, the Fort Carson Army Base requested that NREL evaluate the feasibility of adding a biomass boiler to the district heating system served by Building 1860. We have also developed an Excel-spreadsheet-based decision support tool--specific to the historic loads served by Building 1860--with which users can perform what-if analysis on gas costs, biomass costs, and other parameters. For economic reasons, we do not recommend adding a biomass system at this time.

A comparison of producer gas, biochar, and activated carbon from two distributed scale thermochemical conversion systems used to process forest biomass

Science.gov (United States)

Nathaniel Anderson; J. Greg Jones; Deborah Page-Dumroese; Daniel McCollum; Stephen Baker; Daniel Loeffler; Woodam Chung

2013-01-01

Thermochemical biomass conversion systems have the potential to produce heat, power, fuels and other products from forest biomass at distributed scales that meet the needs of some forest industry facilities. However, many of these systems have not been deployed in this sector and the products they produce from forest biomass have not been adequately described or...

Pyrolysis of corn stalk biomass briquettes in a scaled-up microwave technology.

Science.gov (United States)

Salema, Arshad Adam; Afzal, Muhammad T; Bennamoun, Lyes

2017-06-01

Pyrolysis of corn stalk biomass briquettes was carried out in a developed microwave (MW) reactor supplied with 2.45GHz frequency using 3kW power generator. MW power and biomass loading were the key parameters investigated in this study. Highest bio-oil, biochar, and gas yield of 19.6%, 41.1%, and 54.0% was achieved at different process condition. In terms of quality, biochar exhibited good heating value (32MJ/kg) than bio-oil (2.47MJ/kg). Bio-oil was also characterised chemically using FTIR and GC-MS method. This work may open new dimension towards development of large-scale MW pyrolysis technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Devolatilization characteristics of biomass at flash heating rate

Energy Technology Data Exchange (ETDEWEB)

Xiu Shuangning; Li Zhihe; Li Baoming; Yi Weiming; Bai Xueyuan [China Agricultural University, Beijing (China). College of Water Conservancy and Civil Engineering

2006-03-15

The devolatilization characteristics of biomass (wheat straw, coconut shell, rice husk and cotton stalk) during flash pyrolysis has been investigated on a plasma heated laminar entrained flow reactor (PHLEFR) with average heating rates of 10{sup 4} K/s. These experiments were conducted with steady temperatures between 750 and 900 K, and the particle residence time varied from about 0.115 to 0.240 s. The ash tracer method was introduced to calculate the yield of volatile products at a set temperature and the residence time. This experimental study showed that the yield of volatile products depends both on the final pyrolysis temperature and the residence time. From the results, a comparative analysis was done for the biomasses, and a one-step global model was used to simulate the flash pyrolytic process and predict the yield of volatile products during pyrolysis. The corresponding kinetic parameters of the biomasses were also analyzed and determined. These results were essential for designing a suitable pyrolysis reactor. 24 refs., 5 figs., 5 tabs.

Thermochemical conversion of biomass in smouldering combustion across scales: The roles of heterogeneous kinetics, oxygen and transport phenomena.

Science.gov (United States)

Huang, Xinyan; Rein, Guillermo

2016-05-01

The thermochemical conversion of biomass in smouldering combustion is investigated here by combining experiments and modeling at two scales: matter (1mg) and bench (100g) scales. Emphasis is put on the effect of oxygen (0-33vol.%) and oxidation reactions because these are poorly studied in the literature in comparison to pyrolysis. The results are obtained for peat as a representative biomass for which there is high-quality experimental data published previously. Three kinetic schemes are explored, including various steps of drying, pyrolysis and oxidation. The kinetic parameters are found using the Kissinger-Genetic Algorithm method, and then implemented in a one-dimensional model of heat and mass transfer. The predictions are validated with thermogravimetric and bench-scale experiments and then analyzed to unravel the role of heterogeneous reaction. This is the first time that the influence of oxygen on biomass smouldering is explained in terms of both chemistry and transport phenomena across scales. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Opportunities for biomass-derived 'bio-oil' in European heat and power markets

International Nuclear Information System (INIS)

Brammer, J.G.; Lauer, M.; Bridgwater, A.V.

2006-01-01

Bio-oil (biomass fast pyrolysis) systems for heat, power or CHP production are nearing demonstration status. Their commercial attractiveness will depend on many factors, and will vary with the application, the scale, and importantly the location and its associated economic and logistical factors. The objective of this work, carried out as part of an EC-ALTENER project, was to evaluate the opportunities for bio-oil in the heat and power markets of Europe. Bio-oil applications were compared with conventional (fossil) alternatives for the same heat and power duty. The evaluation was carried out by a quantitative assessment of the economic competitiveness of standard applications in 14 European countries. Location-specific data were collected, and combined with technology-specific data obtained from earlier work. A competitiveness factor (c F ) was derived which represents the total annual cost of a conventional alternative relative to a bio-oil application. The results showed a wide variation across Europe. A total of six countries had at least one bio-oil application which was economically competitive. Heat-only applications were found to be the most economically competitive, followed by CHP applications, with electricity-only applications only very rarely competitive. For a given technology, the larger the scale, the better the competitiveness

Opportunities for biomass-derived 'bio-oil' in European heat and power markets

International Nuclear Information System (INIS)

Brammer, J.G.; Bridgwater, A.V.

2006-01-01

Bio-oil (biomass fast pyrolysis) systems for heat, power or CHP production are nearing demonstration status. Their commercial attractiveness will depend on many factors, and will vary with the application, the scale, and importantly the location and its associated economic and logistical factors. The objective of this work, carried out as part of an EC-ALTENER project, was to evaluate the opportunities for bio-oil in the heat and power markets of Europe. Bio-oil applications were compared with conventional (fossil) alternatives for the same heat and power duty. The evaluation was carried out by a quantitative assessment of the economic competitiveness of standard applications in 14 European countries. Location-specific data were collected, and combined with technology-specific data obtained from earlier work. A competitiveness factor (c F ) was derived which represents the total annual cost of a conventional alternative relative to a bio-oil application. The results showed a wide variation across Europe. A total of six countries had at least one bio-oil application which was economically competitive. Heat-only applications were found to be the most economically competitive, followed by CHP applications, with electricity-only applications only very rarely competitive. For a given technology, the larger the scale, the better the competitiveness. (author)

The scale of biomass production in Japan

Energy Technology Data Exchange (ETDEWEB)

Matsumura, Yukihiko [School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima-shi 739-8527 (Japan); Inoue, Takashi; Fukuda, Katsura [Global Warming Research Department, Mitsubishi Research Institute, Inc., 2-3-6 Ohtemachi, Chiyoda-ku, Tokyo 100-8141 (Japan); Komoto, Keiichi; Hada, Kenichiro [Renewable energy Team, Environment, Natural Resources and Energy Division, Mizuho Information and Research Institute, Inc., 2-3 Kanda-nishikicho, Chiyoda-ku, Tokyo 101-8443 (Japan); Hirata, Satoshi [Technical Institute, Kawasaki Heavy Industries, Ltd., 1-1 Kawasakicho, Akashi-shi, Hyogo 673-8666 (Japan); Minowa, Tomoaki [Biomass Recycle Research Laboratory, National Institute of Advanced and Industrial Science and Technology, 2-2-2 Hiro, Suehiro, Kure-shi, Hiroshima 737-0197 (Japan); Yamamoto, Hiromi [Socioeconomic Research Center, Central Research Institute of Electric Power Industry, 1-6-1 Ohtemachi, Chiyoda-ku, Tokyo 100-8126 (Japan)

2005-11-01

Policymakers working to introduce and promote the use of bioenergy in Japan require detailed information on the scales of the different types of biomass resources generated. In this research, the first of its type in Japan, the investigators reviewed various statistical resources to quantify the scale distribution of forest residues, waste wood from manufacturing, waste wood from construction, cattle manure, sewage sludge, night soil, household garbage, and waste food oil. As a result, the scale of biomass generation in Japan was found to be relatively small, on the average is no more than several tons in dry weight per day. (author)

A review of large-scale solar heating systems in Europe

International Nuclear Information System (INIS)

Fisch, M.N.; Guigas, M.; Dalenback, J.O.

1998-01-01

Large-scale solar applications benefit from the effect of scale. Compared to small solar domestic hot water (DHW) systems for single-family houses, the solar heat cost can be cut at least in third. The most interesting projects for replacing fossil fuels and the reduction of CO 2 -emissions are solar systems with seasonal storage in combination with gas or biomass boilers. In the framework of the EU-APAS project Large-scale Solar Heating Systems, thirteen existing plants in six European countries have been evaluated. lie yearly solar gains of the systems are between 300 and 550 kWh per m 2 collector area. The investment cost of solar plants with short-term storage varies from 300 up to 600 ECU per m 2 . Systems with seasonal storage show investment costs twice as high. Results of studies concerning the market potential for solar heating plants, taking new collector concepts and industrial production into account, are presented. Site specific studies and predesign of large-scale solar heating plants in six European countries for housing developments show a 50% cost reduction compared to existing projects. The cost-benefit-ratio for the planned systems with long-term storage is between 0.7 and 1.5 ECU per kWh per year. (author)

Biomass: towards more co-generation than gasification? Interview with Jean-Christophe Pouet; Figures for the heat fund; biomass in the Parisian heat network; gasification still at the promise stage; Engie bets on bio-methane of 2. generation; a new bidding for biomass co-generation

International Nuclear Information System (INIS)

Petitot, Pauline; De Santis, Audrey; Mary, Olivier; Signoret, Stephane

2016-01-01

After some brief presentations of some highlights in the biomass sector in France, Ukraine, UK and Brazil, a set of articles proposes an overview of recent developments and perspectives for the biomass-based energy and heat production in France. It presents and comments some emerging projects based on biomass gasification as technologies have evolved for a higher economic profitability. It discusses the action of the Heat Fund (Fonds chaleur) which supports investors in a context constrained by the hard competition with fossil energies, notably with gas as discussed in an interview with a member of the ADEME. Some tables and graphs give data about biomass installations supported by the Heat fund, about subsidies awarded by the ADEME, about the production of the various heat sources. An article comments the operation of a biomass-based plant near Paris which supplies the Parisian heat network. A project of methane production from dry biomass from local resources by Engie near Lyons (methane of second generation). The last article comments a new bidding process for co-generation projects which can be an opportunity for new projects, and not only big ones

Thermodynamic modelling of an onsite methanation reactor for upgrading producer gas from commercial small scale biomass gasifiers.

Science.gov (United States)

Vakalis, S; Malamis, D; Moustakas, K

2018-06-15

Small scale biomass gasifiers have the advantage of having higher electrical efficiency in comparison to other conventional small scale energy systems. Nonetheless, a major drawback of small scale biomass gasifiers is the relatively poor quality of the producer gas. In addition, several EU Member States are seeking ways to store the excess energy that is produced from renewables like wind power and hydropower. A recent development is the storage of energy by electrolysis of water and the production of hydrogen in a process that is commonly known as "power-to-gas". The present manuscript proposes an onsite secondary reactor for upgrading producer gas by mixing it with hydrogen in order to initiate methanation reactions. A thermodynamic model has been developed for assessing the potential of the proposed methanation process. The model utilized input parameters from a representative small scale biomass gasifier and molar ratios of hydrogen from 1:0 to 1:4.1. The Villar-Cruise-Smith algorithm was used for minimizing the Gibbs free energy. The model returned the molar fractions of the permanent gases, the heating values and the Wobbe Index. For mixtures of hydrogen and producer gas on a 1:0.9 ratio the increase of the heating value is maximized with an increase of 78%. For ratios higher than 1:3, the Wobbe index increases significantly and surpasses the value of 30 MJ/Nm 3 . Copyright © 2017 Elsevier Ltd. All rights reserved.

Heat transfer corrected isothermal model for devolatilization of thermally-thick biomass particles

DEFF Research Database (Denmark)

Luo, Hao; Wu, Hao; Lin, Weigang

Isothermal model used in current computational fluid dynamic (CFD) model neglect the internal heat transfer during biomass devolatilization. This assumption is not reasonable for thermally-thick particles. To solve this issue, a heat transfer corrected isothermal model is introduced. In this model......, two heat transfer corrected coefficients: HT-correction of heat transfer and HR-correction of reaction, are defined to cover the effects of internal heat transfer. A series of single biomass devitalization case have been modeled to validate this model, the results show that devolatilization behaviors...... of both thermally-thick and thermally-thin particles are predicted reasonable by using heat transfer corrected model, while, isothermal model overestimate devolatilization rate and heating rate for thermlly-thick particle.This model probably has better performance than isothermal model when it is coupled...

Small-Scale Combined Heat and Power Plants Using Biofuels

Energy Technology Data Exchange (ETDEWEB)

Salomon-Popa, Marianne [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

2002-11-01

In this time period where energy supply and climate change are of special concern, biomass-based fuels have attracted much interest due to their plentiful supply and favorable environmental characteristics (if properly managed). The effective capture and continued sustainability of this renewable resource requires a new generation of biomass power plants with high fuel energy conversion. At the same time, deregulation of the electricity market offers new opportunities for small-scale power plants in a decentralized scheme. These two important factors have opened up possibilities for small-scale combined heat and power (CHP) plants based on biofuels. The objective of this pre-study is to assess the possibilities and technical limitations for increased efficiency and energy utilization of biofuels in small size plants (approximately 10 MWe or lower). Various energy conversion technologies are considered and proven concepts for large-scale fossil fuel plants are an especially important area. An analysis has been made to identify the problems, technical limitations and different possibilities as recognized in the literature. Beyond published results, a qualitative survey was conducted to gain first-hand, current knowledge from experts in the field. At best, the survey results together with the results of personal interviews and a workshop on the role of small-scale plants in distributed generation will serve a guideline for future project directions and ideas. Conventional and novel technologies are included in the survey such as Stirling engines, combustion engines, gas turbines, steam turbines, steam motors, fuel cells and other novel technologies/cycles for biofuels. State-of-the-art heat and power plants will be identified to clarify of the advantages and disadvantages as well as possible obstacles for their implementation.

Feasibility of biomass heating system in Middle East Technical University, Northern Cyprus Campus

Directory of Open Access Journals (Sweden)

Samuel Asumadu-Sarkodie

2016-12-01

Full Text Available Global interest in using biomass feedstock to produce heat and power is increasing. In this study, RETScreen modelling software was used to investigate the feasibility of biomass heating system in Middle East Technical University, Northern Cyprus Campus. Weiss Kessel Multicratboiler system with 2 MW capacity using rice straw biomass as fuel and 10 units of RBI® CB0500 boilers with 144 kW capacity using natural gas as fuel were selected for the proposed biomass heating system. The total cost of the biomass heating project is US$ 786,390. The project has a pre-tax and after tax internal rate of return (IRR of 122.70%, simple payback period of 2.54 years, equity payback period of 0.83 year, a net present value of US$ 3,357,138.29, an annual lifecycle savings of US$ 262,617.91, a benefit-cost ratio of 21.83, an electricity cost of $0/kWh and a GHG reduction cost of −204.66 $/tCO₂. The annual GHG emission reduction is 1,283.2 tCO₂, which is equivalent to 118 hectares of forest absorbing carbon. The development and adoption of this renewable energy technology will save costs on buying conventional type of heating system and result in a large technical and economic potential for reducing greenhouse gas emissions which will satisfy the sustainable development goals.

BARRIER ISSUES TO THE UTILIZATION OF BIOMASS

Energy Technology Data Exchange (ETDEWEB)

Bruce C. Folkedahl; Jay R. Gunderson; Darren D. Schmidt; Greg F. Weber; Christopher J. Zygarlicke

2002-09-01

The Energy & Environmental Research Center (EERC) has completed a project to examine fundamental issues that could limit the use of biomass in small industrial steam/power systems in order to increase the future use of this valuable domestic resource. Specifically, the EERC attempted to elucidate the ash-related problems--grate clinkering and heat exchange surface fouling--associated with cofiring coal and biomass in grate-fired systems. Utilization of biomass in stoker boilers designed for coal can be a cause of concern for boiler operators. Boilers that were designed for low-volatile fuels with lower reactivities can experience problematic fouling when switched to higher-volatile and more reactive coal-biomass blends. Higher heat release rates at the grate can cause increased clinkering or slagging at the grate due to higher temperatures. Combustion and loss of volatile matter can start much earlier for biomass fuels compared to design fuel, vaporizing alkali and chlorides which then condense on rear walls and heat exchange tube banks in the convective pass of the stoker, causing noticeable increases in fouling. In addition, stoker-fired boilers that switch to biomass blends may encounter new chemical species such as potassium sulfates, various chlorides, and phosphates. These species in combination with different flue gas temperatures, because of changes in fuel heating value, can adversely affect ash deposition behavior. The goal of this project was to identify the primary ash mechanisms related to grate clinkering and heat exchange surface fouling associated with cofiring coal and biomass--specifically wood and agricultural residuals--in grate-fired systems, leading to future mitigation of these problems. The specific technical objectives of the project were: (1) Modification of an existing pilot-scale combustion system to simulate a grate-fired system. (2) Verification testing of the simulator. (3) Laboratory-scale testing and fuel characterization to

Cost and primary energy efficiency of small-scale district heating systems

International Nuclear Information System (INIS)

Truong, Nguyen Le; Gustavsson, Leif

2014-01-01

Highlights: • We analyzed minimum-cost options for small-scale DHSs under different contexts. • District heat production cost increases with reduced DHS scales. • Fewer technical options are suitable for small-scale DHSs. • Systems with combined technologies are less sensitive to changes in fuel prices. - Abstract: Efficient district heat production systems (DHSs) can contribute to achieving environmental targets and energy security for countries that have demands for space and water heating. The optimal options for a DHS vary with the environmental and social-political contexts and the scale of district heat production, which further depends on the size of the community served and the local climatic conditions. In this study, we design a small-scale, minimum-cost DHS that produces approximately 100 GWh heat per year and estimate the yearly production cost and primary energy use of this system. We consider conventional technologies, such as heat-only boilers, electric heat pumps and combined heat and power (CHP) units, as well as emerging technologies, such as biomass-based organic Rankine cycle (BORC) and solar water heating (SWH). We explore how different environmental and social-political situations influence the design of a minimum-cost DHS and consider both proven and potential technologies for small-scale applications. Our calculations are based on the real heat load duration curve for a town in southern Sweden. We find that the district heat production cost increases and that the potential for cogeneration decreases with smaller district heat production systems. Although the selection of technologies for a minimum-cost DHS depends on environmental and social-political contexts, fewer technical options are suitable for small-scale systems. Emerging technologies such as CHP-BORC and SWH improve the efficiency of primary energy use for heat production, but these technologies are more costly than conventional heat-only boilers. However, systems with

Market Assessment of Biomass Gasification and Combustion Technology for Small- and Medium-Scale Applications

Energy Technology Data Exchange (ETDEWEB)

Peterson, D.; Haase, S.

2009-07-01

This report provides a market assessment of gasification and direct combustion technologies that use wood and agricultural resources to generate heat, power, or combined heat and power (CHP) for small- to medium-scale applications. It contains a brief overview of wood and agricultural resources in the U.S.; a description and discussion of gasification and combustion conversion technologies that utilize solid biomass to generate heat, power, and CHP; an assessment of the commercial status of gasification and combustion technologies; a summary of gasification and combustion system economics; a discussion of the market potential for small- to medium-scale gasification and combustion systems; and an inventory of direct combustion system suppliers and gasification technology companies. The report indicates that while direct combustion and close-coupled gasification boiler systems used to generate heat, power, or CHP are commercially available from a number of manufacturers, two-stage gasification systems are largely in development, with a number of technologies currently in demonstration. The report also cites the need for a searchable, comprehensive database of operating combustion and gasification systems that generate heat, power, or CHP built in the U.S., as well as a national assessment of the market potential for the systems.

A cost-effective evaluation of biomass district heating in rural communities

International Nuclear Information System (INIS)

Hendricks, Aaron M.; Wagner, John E.; Volk, Timothy A.; Newman, David H.; Brown, Tristan R.

2016-01-01

Highlights: • Develop a cost-effective model using secondary data examining delivering heat through Biomass District Heating (BDH). • Eight of ten rural villages studied could cost-effectively deliver heat through BDH below the 2013 price of heating oil. • 80% of the annual cost of BDH was attributable to capital expenses. • Erratic fuel oil prices substantially impact future feasibility. • Village level feasibility is highly-influenced by the presence of large heat demanders. - Abstract: The economic feasibility of Biomass District Heating (BDH) networks in rural villages is largely unknown. A cost-effective evaluation tool is developed to examine the feasibility of BDH in rural communities using secondary data sources. The approach is unique in that it accounts for all the major capital expenses: energy center, distribution network, and energy transfer stations, as well as biomass procurement. BDH would deliver heat below #2 fuel oil in eight of the ten rural study villages examined, saving nearly $500,000 per year in heating expenses while demanding less than 5% of the forest residues sustainably available regionally. Capital costs comprised over 80% of total costs, illuminating the importance of reaching a sufficient heat density. Reducing capital costs by 1% lowers total cost by $93,000 per year. Extending capital payment period length five years or lowering interest rates has the next highest influence decreasing delivered heat price 0.49% and 0.35% for each 1% change, respectively. This highlights that specific building heat is a strong determinant of feasibility given the relative influence of high-demanding users on the overall village heat-density. Finally, we use a stochastic analysis projecting future #2 fuel oil prices, incorporating historical variability, to determine the probability of future BDH feasibility. Although future oil prices drop below the BDH feasibility threshold, the villages retain a 22–53% probability of feasibility after

Flexibility of Large-Scale Solar Heating Plant with Heat Pump and Thermal Energy Storage

DEFF Research Database (Denmark)

Luc, Katarzyna Marta; Heller, Alfred; Rode, Carsten

2017-01-01

to decrease biomass use in a district heating system. The paper focuses on the renewable energy-based district heating system in Marstal, Denmark, with heat produced in central solar heating plant, wood pellet boiler, heat pump and bio-oil boiler. The plant has been the object of research and developments...

BARRIER ISSUES TO THE UTILIZATION OF BIOMASS; SEMIANNUAL

International Nuclear Information System (INIS)

Bruce C. Folkedahl; Darren D. Schmidt; Greg F. Weber; Christopher J. Zygarlicke

2001-01-01

The Energy and Environmental Research Center (EERC) is conducting a project to examine the fundamental issues limiting the use of biomass in small industrial steam/power systems in order to increase the future use of this valuable domestic resource. Specifically, the EERC is attempting to elucidate the ash-related problems-grate clinkering and heat exchange surface fouling-associated with cofiring coal and biomass in grate-fired systems. Utilization of biomass in stoker boilers designed for coal can be a cause of concern for boiler operators. Boilers that were designed for low volatile fuels with lower reactivities can experience damaging fouling when switched to higher volatile and more reactive lower-rank fuels, such as when cofiring biomass. Higher heat release rates at the grate can cause more clinkering or slagging at the grate because of higher temperatures. Combustion and loss of volatile matter can start too early for biomass fuels compared to the design fuel, vaporizing alkali and chlorides which then condense on rear walls and heat exchange tube banks in the convective pass of the stoker, causing noticeable increases in fouling. In addition, stoker-fired boilers that switch to biomass blends may encounter new chemical species such as potassium sulfates and various chlorides, in combination with different flue gas temperatures because of changes in fuel heating value which can adversely affect ash deposition behavior. The goal of this project is to identify the primary ash mechanisms related to grate clinkering and heat exchange surface fouling associated with cofiring coal and biomass-specifically wood and agricultural residuals-in grate-fired systems, leading to future mitigation of these problems. The specific technical objectives of the project are: Modification of an existing EERC pilot-scale combustion system to simulate a grate-fired system; Verification testing of the simulator; Laboratory-scale testing and fuel characterization to determine ash

Termisk forgasning af biomasse

DEFF Research Database (Denmark)

Henriksen, Ulrik Birk

2005-01-01

The title of this Ph.D. thesis is: Thermal Gasification of Biomass. Compilation of activities in the ”Biomass Gasification Group” at Technical University of Denmark (DTU). This thesis gives a presentation of selected activities in the Biomass Gasification Group at DTU. The activities are related...... to thermal gasification of biomass. Focus is on gasification for decentralised cogeneration of heat and power, and on related research on fundamental processes. In order to insure continuity of the presentation the other activities in the group, have also been described. The group was started in the late...... of these activities has been fruitful. The two- stage gasifier was developed for gasification aiming at decentralised cogeneration of heat and power. The development ranged from lap-top scale equipment to a fully automatic plant with more than 2000 hours of operation. Compared to most other gasification processes...

Controlling the excess heat from oxy-combustion of coal by blending with biomass

Energy Technology Data Exchange (ETDEWEB)

Haykiri-Acma, H.; Turan, A.Z.; Yaman, S.; Kucukbayrak, S. [Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Chemical Engineering Department, 34469, Maslak, Istanbul (Turkey)

2010-11-15

Two different biomass species such as sunflower seed shell and hazelnut shell were blended with Soma-Denis lignite to determine the effects of co-combustion on the thermal reactivity and the burnout of the lignite sample. For this purpose, Thermogravimetric Analysis and Differential Scanning Calorimetry techniques were applied from ambient to 900 C with a heating rate of 40 C/min under dry air and pure oxygen conditions. It was found that the thermal reactivities of the biomass materials and the lignite are highly different from each other under each oxidizing medium. On the other hand, the presence of biomass in the burning medium led to important influences not only on the burnout levels but also on the heat flows. The heat flow from the burning of lignite increased fivefold when the oxidizing medium was altered from dry air to pure oxygen. But, in case of co-combustion under oxygen, the excess heat arising from combustion of lignite could be reduced and this may be helpful to control the temperature of the combustion chamber. Based on this, co-combustion of coal/biomass blends under oxygen may be suggested as an alternative method to the ''Carbon Dioxide Recycle Method'' encountered in the oxyfuel combustion systems. (author)

Scaling up biomass gasifier use: an application-specific approach

International Nuclear Information System (INIS)

Ghosh, Debyani; Sagar, Ambuj D.; Kishore, V.V.N.

2006-01-01

Biomass energy accounts for about 11% of the global primary energy supply, and it is estimated that about 2 billion people worldwide depend on biomass for their energy needs. Yet, most of the use of biomass is in a primitive and inefficient manner, primarily in developing countries, leading to a host of adverse implications on human health, environment, workplace conditions, and social well being. Therefore, the utilization of biomass in a clean and efficient manner to deliver modern energy services to the world's poor remains an imperative for the development community. One possible approach to do this is through the use of biomass gasifiers. Although significant efforts have been directed towards developing and deploying biomass gasifiers in many countries, scaling up their dissemination remains an elusive goal. Based on an examination of biomass gasifier development, demonstration, and deployment efforts in India-a country with more than two decades of experiences in biomass gasifier development and dissemination, this article identifies a number of barriers that have hindered widespread deployment of biomass gasifier-based energy systems. It also suggests a possible approach for moving forward, which involves a focus on specific application areas that satisfy a set of criteria that are critical to deployment of biomass gasifiers, and then tailoring the scaling up strategy to the characteristics of the user groups for that application. Our technical, financial, economic and institutional analysis suggests an initial focus on four categories of applications-small and medium enterprises, the informal sector, biomass-processing industries, and some rural areas-may be particularly feasible and fruitful

An applied methodology for assessment of the sustainability of biomass district heating systems

Science.gov (United States)

Vallios, Ioannis; Tsoutsos, Theocharis; Papadakis, George

2016-03-01

In order to maximise the share of biomass in the energy supplying system, the designers should adopt the appropriate changes to the traditional systems and become more familiar with the design details of the biomass heating systems. The aim of this study is to present the development of methodology and its associated implementation in software that is useful for the design of biomass thermal conversion systems linked with district heating (DH) systems, taking into consideration the types of building structures and urban settlement layout around the plant. The methodology is based on a completely parametric logic, providing an impact assessment of variations in one or more technical and/or economic parameters and thus, facilitating a quick conclusion on the viability of this particular energy system. The essential energy parameters are presented and discussed for the design of biomass power and heat production system which are in connection with DH network, as well as for its environmental and economic evaluation (i.e. selectivity and viability of the relevant investment). Emphasis has been placed upon the technical parameters of biomass logistics, energy system's design, the economic details of the selected technology (integrated cogeneration combined cycle or direct combustion boiler), the DH network and peripheral equipment (thermal substations) and the greenhouse gas emissions. The purpose of this implementation is the assessment of the pertinent investment financial viability taking into account the available biomass feedstock, the economical and market conditions, and the capital/operating costs. As long as biomass resources (forest wood and cultivation products) are available and close to the settlement, disposal and transportation costs of biomass, remain low assuring the sustainability of such energy systems.

Air pollution reduction with respect to the conversion of biomass into electricity and heat. Emission and cost indexes

International Nuclear Information System (INIS)

Bergsma, G.C.; Croezen, H.C.; De Weerd, G.; Van der Werff, T.

1999-01-01

Although biomass conversion is considered to be a CO2-free method of producing electricity and heat other emissions have to be taken into account: SO2, NOx, HCl, HF, Hg, Cd, dusts, etc. The aim of the study on the title subject is to support the Dutch Ministry of Housing, Planning and Environment (VROM) in the determination of feasible emission standards for bioconversion installations. The Centre for Energy conservation and clean technology (CE) compiled information on the costs for flue gas purification for different degrees of purification. Because of the fact that the composition of flue gases strongly depends on the biomass flow and the applied conversion technique, both biomass flows and conversion techniques must be distinguished. The following biomass conversion techniques were studied: large-scale combustion of wood wastes and sludges, large-scale gasification of wood wastes, cocombustion of wood wastes and sludges, small-scale combustion of wood wastes and chicken manure, small-scale gasification of wood wastes, and fermentation of wastes from vegetables, fruits and gardens. For each combination it is determined what the emissions are in case of a minimal flue gas purification, what the emissions are and how much additional costs are involved in case the regulations in the BLA (decree on air pollution of waste incineration) are taken into account, and what the emissions are and how much additional costs are involved for a number of levels in between the two fore-mentioned cases. refs

Development of a modified equilibrium model for biomass pilot-scale fluidized bed gasifier performance predictions

International Nuclear Information System (INIS)

Rodriguez-Alejandro, David A.; Nam, Hyungseok; Maglinao, Amado L.; Capareda, Sergio C.; Aguilera-Alvarado, Alberto F.

2016-01-01

The objective of this work is to develop a thermodynamic model considering non-stoichiometric restrictions. The model validation was done from experimental works using a bench-scale fluidized bed gasifier with wood chips, dairy manure, and sorghum. The model was used for a further parametric study to predict the performance of a pilot-scale fluidized biomass gasifier. The Gibbs free energy minimization was applied to the modified equilibrium model considering a heat loss to the surroundings, carbon efficiency, and two non-equilibrium factors based on empirical correlations of ER and gasification temperature. The model was in a good agreement with RMS <4 for the produced gas. The parametric study ranges were 0.01 < ER < 0.99 and 500 °C < T < 900 °C to predict syngas concentrations and its LHV (lower heating value) for the optimization. Higher aromatics in tar were contained in WC gasification compared to manure gasification. A wood gasification tar simulation was produced to predict the amount of tars at specific conditions. The operating conditions for the highest quality syngas were reconciled experimentally with three biomass wastes using a fluidized bed gasifier. The thermodynamic model was used to predict the gasification performance at conditions beyond the actual operation. - Highlights: • Syngas from experimental gasification was used to create a non-equilibrium model. • Different types of biomass (HTS, DM, and WC) were used for gasification modelling. • Different tar compositions were identified with a simulation of tar yields. • The optimum operating conditions were found through the developed model.

Integration of biomass into urban energy systems for heat and power. Part I: An MILP based spatial optimization methodology

International Nuclear Information System (INIS)

Pantaleo, Antonio M.; Giarola, Sara; Bauen, Ausilio; Shah, Nilay

2014-01-01

Highlights: • MILP tool for optimal sizing and location of heating and CHP plants to serve residential energy demand. • Trade-offs between local vs centralized heat generation, district heating vs natural gas distribution systems. • Assessment of multi-biomass supply chains and biomass to biofuel processing technologies. • Assessment of the key factors influencing the use of biomass and district heating in residential areas. - Abstract: The paper presents a mixed integer linear programming (MILP) approach to optimize multi-biomass and natural gas supply chain strategic design for heat and power generation in urban areas. The focus is on spatial and temporal allocation of biomass supply, storage, processing, transport and energy conversion (heat and CHP) to match the heat demand of residential end users. The main aim lies on the representation of the relationships between the biomass processing and biofuel energy conversion steps, and on the trade-offs between centralized district heating plants and local heat generation systems. After a description of state of the art and research trends in urban energy systems and bioenergy modelling, an application of the methodology to a generic case study is proposed. With the assumed techno-economic parameters, biomass based thermal energy generation results competitive with natural gas, while district heating network results the main option for urban areas with high thermal energy demand density. Potential further applications of this model are also described, together with main barriers for development of bioenergy routes for urban areas

Biomass District Heat System for Interior Rural Alaska Villages

Energy Technology Data Exchange (ETDEWEB)

Wall, William A.; Parker, Charles R.

2014-09-01

Alaska Village Initiatives (AVI) from the outset of the project had a goal of developing an integrated village approach to biomass in Rural Alaskan villages. A successful biomass project had to be ecologically, socially/culturally and economically viable and sustainable. Although many agencies were supportive of biomass programs in villages none had the capacity to deal effectively with developing all of the tools necessary to build a complete integrated program. AVI had a sharp learning curve as well. By the end of the project with all the completed tasks, AVI developed the tools and understanding to connect all of the dots of an integrated village based program. These included initially developing a feasibility model that created the capacity to optimize a biomass system in a village. AVI intent was to develop all aspects or components of a fully integrated biomass program for a village. This meant understand the forest resource and developing a sustainable harvest system that included the “right sized” harvest equipment for the scale of the project. Developing a training program for harvesting and managing the forest for regeneration. Making sure the type, quality, and delivery system matched the needs of the type of boiler or boilers to be installed. AVI intended for each biomass program to be of the scale that would create jobs and a sustainable business.

Thermodynamic modeling and evaluation of high efficiency heat pipe integrated biomass Gasifier–Solid Oxide Fuel Cells–Gas Turbine systems

International Nuclear Information System (INIS)

Santhanam, S.; Schilt, C.; Turker, B.; Woudstra, T.; Aravind, P.V.

2016-01-01

This study deals with the thermodynamic modeling of biomass Gasifier–SOFC (Solid Oxide Fuel Cell)–GT (Gas Turbine) systems on a small scale (100 kW_e). Evaluation of an existing biomass Gasifier–SOFC–GT system shows highest exergy losses in the gasifier, gas turbine and as waste heat. In order to reduce the exergy losses and increase the system's efficiency, improvements are suggested and the effects are analyzed. Changing the gasifying agent for air to anode gas gave the largest increase in the electrical efficiency. However, heat is required for an allothermal gasification to take place. A new and simple strategy for heat pipe integration is proposed, with heat pipes placed in between stacks in series, rather than the widely considered approach of integrating the heat pipes within the SOFC stacks. The developed system based on a Gasifier–SOFC–GT combination improved with heat pipes and anode gas recirculation, increases the electrical efficiency from approximately 55%–72%, mainly due to reduced exergy losses in the gasifier. Analysis of the improved system shows that operating the system at possibly higher operating pressures, yield higher efficiencies within the range of the operating pressures studied. Further the system was scaled up with an additional bottoming cycle achieved electrical efficiency of 73.61%. - Highlights: • A new and simple strategy for heat pipe integration between SOFC and Gasifier is proposed. • Anode exhaust gas is used as a gasifying agent. • The new proposed Gasifier–SOFC–GT system achieves electrical efficiency of 72%. • Addition of steam rankine bottoming cycle to proposed system increases electrical efficiency to 73.61%.

Fossil fuel and biomass burning effect on climate - heating or cooling

Energy Technology Data Exchange (ETDEWEB)

Kaufman, Y.J.; Fraser, R.S.; Mahoney, R.L. (NASA/Goddard Space Flight Center, Greenbelt, MD (USA))

1991-06-01

Emission from burning of fossil fuels and biomass (associated with deforestation) generates a radiative forcing on the atmosphere and a possible climate change. Emitted trace gases heat the atmosphere through their greenhouse effect, while particulates formed from emitted SO{sub 2} cause cooling by increasing cloud albedos through alteration of droplet size distributions. This paper reviews the characteristics of the cooling effect and applies Twomey's theory to check whether the radiative balance favours heating or cooling for the cases of fossil fuel and biomass burning. It is also shown that although coal and oil emit 120 times as many CO{sub 2} molecules as SO{sub 2} molecules, each SO{sub 2} molecule is 50-1100 times more effective in cooling the atmosphere (through the effect of aerosol particles on cloud albedo) than a CO{sub 2} molecule is in heating it. Note that this ratio accounts for the large difference in the aerosol (3-10 days) and CO{sub 2} (7-100 years) lifetimes. It is concluded, that the cooling effect from coal and oil burning may presently range from 0.4 to 8 times the heating effect. Within this large uncertainty, it is presently more likely that fossil fuel burning causes cooling of the atmosphere rather than heating. Biomass burning associated with deforestation, on the other hand, is more likely to cause heating of the atmosphere than cooling since its aerosol cooling effect is only half that from fossil fuel burning and its heating effect is twice as large. Future increases in coal and oil burning, and the resultant increase in concentration of cloud condensation nuclei, may saturate the cooling effect, allowing the heating effect to dominate. For a doubling in the CO{sub 2} concentration due to fossil fuel burning, the cooling effect is expected to be 0.1 to 0.3 of the heating effect. 75 refs., 8 tabs.

Experimental methods for laboratory-scale ensilage of lignocellulosic biomass

International Nuclear Information System (INIS)

Tanjore, Deepti; Richard, Tom L.; Marshall, Megan N.

2012-01-01

Anaerobic fermentation is a potential storage method for lignocellulosic biomass in biofuel production processes. Since biomass is seasonally harvested, stocks are often dried or frozen at laboratory scale prior to fermentation experiments. Such treatments prior to fermentation studies cause irreversible changes in the plant cells, influencing the initial state of biomass and thereby the progression of the fermentation processes itself. This study investigated the effects of drying, refrigeration, and freezing relative to freshly harvested corn stover in lab-scale ensilage studies. Particle sizes, as well as post-ensilage drying temperatures for compositional analysis, were tested to identify the appropriate sample processing methods. After 21 days of ensilage the lowest pH value (3.73 ± 0.03), lowest dry matter loss (4.28 ± 0.26 g. 100 g-1DM), and highest water soluble carbohydrate (WSC) concentrations (7.73 ± 0.26 g. 100 g-1DM) were observed in control biomass (stover ensiled within 12 h of harvest without any treatments). WSC concentration was significantly reduced in samples refrigerated for 7 days prior to ensilage (3.86 ± 0.49 g. 100 g −1 DM). However, biomass frozen prior to ensilage produced statistically similar results to the fresh biomass control, especially in treatments with cell wall degrading enzymes. Grinding to decrease particle size reduced the variance amongst replicates for pH values of individual reactors to a minor extent. Drying biomass prior to extraction of WSCs resulted in degradation of the carbohydrates and a reduced estimate of their concentrations. The methods developed in this study can be used to improve ensilage experiments and thereby help in developing ensilage as a storage method for biofuel production. -- Highlights: ► Laboratory-scale methods to assess the influence of ensilage biofuel production. ► Drying, freezing, and refrigeration of biomass influenced microbial fermentation. ► Freshly ensiled stover exhibited

Interactive economic analysis of small-scale heating plant

Energy Technology Data Exchange (ETDEWEB)

Landen, R.A.; Sanders, D.L.; Douglas, B.H.

1998-11-01

This report contains the work that has been undertaken by LRZ Limited in pursuance of this agreement. The potential for small-scale biomass heating systems is identified, and surrounding issues relating to acceptance are discussed. Such systems are described, and the origins of capital and running costs examined. A full review of the calculation methods for boiler plant size and fuel consumption is made, and subsequently expounded in four varying case studies. The results of this work are discussed, and the final development of the computer models is reviewed, incorporating further refinements to the method. Finally, data not contained in the text is incorporated in comprehensive appendices. (author)

Grate-firing of biomass for heat and power production

DEFF Research Database (Denmark)

Yin, Chungen; Rosendahl, Lasse; Kær, Søren Knudsen

2008-01-01

bed on the grate, and the advanced secondary air supply (a real breakthrough in this technology) are highlighted for grate-firing systems. Amongst all the issues or problems associated with grate-fired boilers burning biomass, primary pollutant formation and control, deposition formation and corrosion......As a renewable and environmentally friendly energy source, biomass (i.e., any organic non-fossil fuel) and its utilization are gaining an increasingly important role worldwide Grate-firing is one of the main competing technologies in biomass combustion for heat and power production, because it can...... combustion mechanism, the recent breakthrough in the technology, the most pressing issues, the current research and development activities, and the critical future problems to be resolved. The grate assembly (the most characteristic element in grate-fired boilers), the key combustion mechanism in the fuel...

Results with a bench scale downdraft biomass gasifier for agricultural and forestry residues

Energy Technology Data Exchange (ETDEWEB)

Olgun, Hayati [TUBITAK Marmara Research Center, Energy Institute, P.O. Box 21, 41470 Gebze, Kocaeli (Turkey); Ozdogan, Sibel; Yinesor, Guzide [Marmara University-Goztepe Campus, Faculty of Engineering - Department of Mechanical Engineering, 34722 Kuyubasi Kadikoy Istanbul (Turkey)

2011-01-15

A small scale fixed bed downdraft gasifier system to be fed with agricultural and forestry residues has been designed and constructed. The downdraft gasifier has four consecutive reaction zones from the top to the bottom, namely drying, pyrolysis, oxidation and reduction zones. Both the biomass fuel and the gases move in the same direction. A throat has been incorporated into the design to achieve gasification with lower tar production. The experimental system consists of the downdraft gasifier and the gas cleaning unit made up by a cyclone, a scrubber and a filter box. A pilot burner is utilized for initial ignition of the biomass fuel. The product gases are combusted in the flare built up as part of the gasification system. The gasification medium is air. The air to fuel ratio is adjusted to produce a gas with acceptably high heating value and low pollutants. Within this frame, different types of biomass, namely wood chips, barks, olive pomace and hazelnut shells are to be processed. The developed downdraft gasifier appears to handle the investigated biomass sources in a technically and environmentally feasible manner. This paper summarizes selected design related issues along with the results obtained with wood chips and hazelnut shells. (author)

Fluid selection for the Organic Rankine Cycle (ORC) in biomass power and heat plants

International Nuclear Information System (INIS)

Drescher, Ulli; Brueggemann, Dieter

2007-01-01

In small solid biomass power and heat plants, the ORC is used for cogeneration. This application shows constraints different from other ORC. These constraints are described and an adapted power plant design is presented. The new design influences the selection criteria of working fluids. A software has been developed to find thermodynamic suitable fluids for ORC in biomass power and heat plants. Highest efficiencies are found within the family of alkylbenzenes

The UNDP/World Bank monitoring program on small scale biomass gasifiers (BTG's experience on tar measurements)

Energy Technology Data Exchange (ETDEWEB)

Knoef, H.A.M. [Biomass Technology Group BTG, Enschede (Netherlands)

2000-07-01

By the time that small-scale biomass gasifiers were 'rediscovered' and promoted for use in developing countries (1970s), UNDP and the World Bank were well aware of the pitfalls of previous attempts to diffuse decentralized energy technologies. Therefore they decided to initiate a technology assessment programme before endorsing and/or stimulating a widespread gasifier introduction programme in developing countries. On July 1, 1983, the UNDP/WB worldwide Small-scale biomass gasifier monitoring was initiated, which was to {sup c}ollect uniform data on the actual field performance, economics, safety and public acceptability of biomass gasifiers currently operating in developing countries{sup .} For the UNDP/WB program BTG developed a tar measuring protocol which was used at twenty gasifiers worldwide (Indonesia, Philippines, Brazil, Mali, Seychelles, Vanuatu and Burundi). Other parameters monitored include pressure and temperatures at various spots, gasflow, fuel consumption, lubrication oil analyses, gas-composition analyses, emission measurements. The seven year programme showed that most of donor funded projects failed, mainly because there was not sufficient commitment from involved parties. National programs on the utilization of loca available biomass resources mostly failed because the fuel did not suit the requirements of gasifier reactor. In case of proper project design/set-up most of the small scale biomass gasifiers operated without major problems. Examples of such projects are the ones in Balong and Majalengka (Indonesia) Onesua (Vanuatu), Espara Feliz (Brazil) and Dogofiry (Mali). A motivated team of technicians, operators, managers is one the most important items within this respect. Most of the heat gasifiers are installed commercially and are much more successful compared to the subsidized power gasifiers. Local manufactured gasifiers are generally constructed of low quality materials causing frequent technical problems. However, locally

Biomass fuels in district heating systems. Final report. Biobrensel i fjernvarmesystem. Sluttrapport

Energy Technology Data Exchange (ETDEWEB)

Otterstad, B.

1987-02-01

The report deals with an energy conservation project on district heating. The project gives a cost comparison between a biomass fuelled system for the local water heating/electric power supply and the development of hydroelectric power. The computer program ESENTRAL is used in the simulation. 3 drawings.

The role of domestic biomass in electricity, heat and grid balancing markets in Switzerland

International Nuclear Information System (INIS)

Panos, Evangelos; Kannan, Ramachandran

2016-01-01

The Swiss Energy Strategy targets to reduce per capita energy consumption, to decrease the share of fossil energy and to replace nuclear electricity generation by gains in efficiency and renewable energy sources. In view of the above objectives, we evaluated the prospects of biomass in stationary applications and grid balancing from an energy system perspective. We quantify a number of “what-if” scenarios using a cost-optimisation bottom-up model, with detailed representation of biomass production and use pathways, electricity and heat sectors, and grid ancillary services markets. The scenario analysis shows that domestic biomass can contribute 5–7% in electricity and 14–21% in heat production by 2050, depending on natural gas prices and climate policy intensity. Pooling of biogenic driven cogeneration plants can provide about 22–44% of the total secondary control power in 2050. Generally, biogenic technologies complement other assets in heat, electricity and ancillary services markets such as heat pumps, new renewable sources and hydropower. - Highlights: • Development and application of the Swiss TIMES electricity and heat system model. • Bioenergy supplies 5–7% of electricity and 14–21% of heat by 2050. • Biogenic gas driven CHP can provide 22–44% of secondary control power in 2050.

Fossil fuel and biomass burning effect on climate - Heating or cooling?

Science.gov (United States)

Kaufman, Yoram J.; Fraser, Robert S.; Mahoney, Robert L.

1991-01-01

The basic theory of the effect of pollution on cloud microphysics and its global implications is applied to compare the relative effect of a small increase in the consumption rate of oil, coal, or biomass burning on cooling and heating of the atmosphere. The characteristics of and evidence for the SO2 induced cooling effect are reviewed. This perturbation analysis approach permits linearization, therefore simplifying the analysis and reducing the number of uncertain parameters. For biomass burning the analysis is restricted to burning associated with deforestation. Predictions of the effect of an increase in oil or coal burning show that within the present conditions the cooling effect from oil and coal burning may range from 0.4 to 8 times the heating effect.

Performance of an effectively integrated biomass multi-stage gasification system and a steel industry heat treatment furnace

International Nuclear Information System (INIS)

Gunarathne, Duleeka Sandamali; Mellin, Pelle; Yang, Weihong; Pettersson, Magnus; Ljunggren, Rolf

2016-01-01

Highlights: • Multi-stage biomass gasification is integrated with steel heat treatment furnace. • Fossil fuel derived CO_2 emission is eliminated by replacing natural gas with syngas. • The integrated system uses waste heat from the furnace for biomass gasification. • Up to 13% increment of the gasifier system energy efficiency is observed. • Fuel switching results in 10% lower flue gas loss and improved furnace efficiency. - Abstract: The challenges of replacing fossil fuel with renewable energy in steel industry furnaces include not only reducing CO_2 emissions but also increasing the system energy efficiency. In this work, a multi-stage gasification system is chosen for the integration with a heat treatment furnace in the steel powder industry to recover different rank/temperature waste heat back to the biomass gasification system, resulting higher system energy efficiency. A system model based on Aspen Plus was developed for the proposed integrated system considering all steps, including biomass drying, pyrolysis, gasification and the combustion of syngas in the furnace. Both low temperature (up to 400 °C) and high temperature (up to 700 °C) heat recovery possibilities were analysed in terms of energy efficiency by optimizing the biomass pretreatment temperature. The required process conditions of the furnace can be achieved by using syngas. No major changes to the furnace, combustion technology or flue gas handling system are necessary for this fuel switching. Only a slight revamp of the burner system and a new waste heat recovery system from the flue gases are required. Both the furnace efficiency and gasifier system efficiency are improved by integration with the waste heat recovery. The heat recovery from the hot furnace flue gas for biomass drying and steam superheating is the most promising option from an energy efficiency point of view. This option recovers two thirds of the available waste heat, according to the pinch analysis performed

Driftless Area Initiative Biomass Energy Project

Energy Technology Data Exchange (ETDEWEB)

Wright, Angie [Northeast Iowa Resource Conservation & Development, Inc., Postville, IA (United States); Bertjens, Steve [Natural Resources Conservation Service, Madison, WI (United States); Lieurance, Mike [Northeast Iowa Resource Conservation & Development, Inc., Postville, IA (United States); Berguson, Bill [Univ. of Minnesota, Minneapolis, MN (United States). Natural Resources Research Inst.; Buchman, Dan [Univ. of Minnesota, Minneapolis, MN (United States). Natural Resources Research Inst.

2012-12-31

The Driftless Area Initiative Biomass Energy Project evaluated the potential for biomass energy production and utilization throughout the Driftless Region of Illinois, Iowa, Minnesota and Wisconsin. The research and demonstration aspect of the project specifically focused on biomass energy feedstock availability and production potential in the region, as well as utilization potential of biomass feedstocks for heat, electrical energy production, or combined heat and power operations. The Driftless Region was evaluated because the topography of the area offers more acres of marginal soils on steep slopes, wooded areas, and riparian corridors than the surrounding “Corn Belt”. These regional land characteristics were identified as potentially providing opportunity for biomass feedstock production that could compete with traditional agriculture commodity crops economically. The project researched establishment methods and costs for growing switchgrass on marginal agricultural lands to determine the economic and quantitative feasibility of switchgrass production for biomass energy purposes. The project was successful in identifying the best management and establishment practices for switchgrass in the Driftless Area, but also demonstrated that simple economic payback versus commodity crops could not be achieved at the time of the research. The project also analyzed the availability of woody biomass and production potential for growing woody biomass for large scale biomass energy production in the Driftless Area. Analysis determined that significant resources exist, but costs to harvest and deliver to the site were roughly 60% greater than that of natural gas at the time of the study. The project contributed significantly to identifying both production potential of biomass energy crops and existing feedstock availability in the Driftless Area. The project also analyzed the economic feasibility of dedicated energy crops in the Driftless Area. High commodity crop prices

Volume changes upon heating of aerosol particles from biomass burning using transmission electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Adachi, Kouji [Meteorological Research Inst., Tsukuba (Japan). Atmospheric Environment and Applied Meteorology Research Dept.; Sedlacek, Arthur J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Environmental and Climate Sciences; Kleinman, Lawrence [Brookhaven National Lab. (BNL), Upton, NY (United States). Environmental and Climate Sciences; Chand, Duli [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Atmospheric Sciences and Global Change Division; Hubbe, John M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Atmospheric Sciences and Global Change Division; Buseck, Peter R. [Arizona State Univ., Tempe, AZ (United States). School of Earth and Space Exploration and School of Molecular Sciences

2017-09-26

The responses of aerosol particles to heating are important for measurements of their chemical, physical, and optical properties, classification, and determination of origin. However, the thermal behavior of organic aerosol particles is largely unknown. We provide a method to analyze such thermal behavior through heating from room temperature to >600°C by using a heating holder within a transmission electron microscope (TEM). Here we describe in-situ shape and size changes and variations in the compositions of individual particles before and after heating. We use ambient samples from wildland and agricultural biomass fires in North America collected during the 2013 Biomass Burn Observation Project (BBOP). The results indicate that individual tar balls (TB; spherical organic material) from biomass burning retained, on average, up to 30% of their volume when heated to 600°C. Chemical analysis reveals that K and Na remain in the residues, whereas S and O were lost. In contrast to bulk sample measurements of carbonaceous particles using thermal/optical carbon analyzers, our single-particle results imply that many individual organic particles consist of multiple types of organic matter having different thermal stabilities. Beyond TBs, our results suggest that because of their thermal stability some organic particles may not be detectable by using aerosol mass spectrometry or thermal/optical carbon analyzers. This result can lead to an underestimate of the abundance of TBs and other organic particles, and therefore biomass burning may have more influence than currently recognized in regional and global climate models.

Combined heat and power production through biomass gasification with 'Heatpipe-Reformer'

International Nuclear Information System (INIS)

Iliev, I.; Kamburova, V.; Terziev, A.

2013-01-01

The current report aims is to analyze the system for combined heat and power production through biomass gasification with “heatpipe-reformer” system. Special attention is paid on the process of synthetic gas production in the Reformer, its cleaning and further burning in the co-generation unit. A financial analysis is made regarding the investments and profits generated by the combined heat and power production. (authors)

Potential utilization of biomass in production of electricity, heat and transportation fuels including energy combines - Regional analyses and examples; Potentiell avsaettning av biomassa foer produktion av el, vaerme och drivmedel inklusive energikombinat - Regionala analyser och raekneexempel

Energy Technology Data Exchange (ETDEWEB)

Ericsson, Karin; Boerjesson, Paal

2008-01-15

The objective of this study is to analyse how the use of biomass may increase in the next 10-20 years in production of heat, electricity and transportation fuels in Sweden. In these analyses, the biomass is assumed to be used in a resource and cost efficient way. This means for example that the demand for heat determines the potential use of biomass in co-generation of heat and electricity and in energy combines, and that the markets for by-products determine the use of biomass in production of certain transportation fuels. The economic conditions are not analysed in this study. In the heat and electricity production sector, we make regional analyses of the potential use of biomass in production of small-scale heat, district heat, process heat in the forest industry and electricity produced in co-generation with heat in the district heating systems and forest industry. These analyses show that the use of biomass in heat and electricity production could increase from 87 TWh (the use in 2004/2005, excluding small-scale heat production with firewood) to between 113 TWh and 134 TWh, depending on the future expansion of the district heating systems. Geographically, the Stockholm province accounts for a large part of the potential increase owing to the great opportunities for increasing the use of biomass in production of district heat and CHP in this region. In the sector of transportation fuels we applied a partly different approach since we consider the market for biomass-based transportation fuels to be 'unconstrained' within the next 10-20 years. Factors that constrain the production of these fuels are instead the availability of biomass feedstock and the local conditions required for achieving effective production systems. Among the first generation biofuels this report focuses on RME and ethanol from cereals. We estimate that the domestic production of RME and ethanol could amount to up to 1.4 TWh/y and 0.7-3.8 TWh/y, respectively, where the higher figure

Biomass in Switzerland. Energy production

International Nuclear Information System (INIS)

Guggisberg, B.

2006-01-01

In the long term, biomass could be used for energy production in a three times more intensive way, compared to current figures. A major contribution would be delivered to Switzerland's energy supply. Numerous biomass conversion technologies do exist, for the production of heat, power or vehicle fuel. However, the implementation of such a large-scale utilisation of biomass requires a couple of strategic decisions in order to improve the framework conditions for biomass development and precisely target the supporting measures applicable to both research and pilot plants. In short, a clear and efficient strategy is necessary in what regards biomass, that will be used for the definition of a future catalogue of measures. (author)

Energy from Biomass: technology assessment of small-medium scale biomass conversion systems

OpenAIRE

Cutz Ijchajchal, Luis Leonardo

2016-01-01

Mención Internacional en el título de doctor Bioenergy is a key resource to addressing challenges such as climate change (anthropogenic CO₂ emissions), pollution (suspended particles), energy security and human well-being. Currently, most of the biomass produced worldwide is consumed for cooking and space heating which has raised concerns among governments and policy-makers, especially due to threats to human health. The present thesis focuses on studying the technical and economic feasibi...

Biomass Gasification - A synthesis of technical barriers and current research issues for deployment at large scale

Energy Technology Data Exchange (ETDEWEB)

Heyne, Stefan [Chalmers Univ. of Technology, Gothenburg (Sweden); Liliedahl, Truls [KTH, Royal Inst. of Technology, Stockholm (Sweden); Marklund, Magnus [Energy Technology Centre, Piteaa (Sweden)

2013-09-01

Thermal gasification at large scale for cogeneration of power and heat and/or production of fuels and materials is a main pathway for a sustainable deployment of biomass resources. However, so far no such full scale production exists and biomass gasification projects remain at the pilot or demonstration scale. This report focuses on the key critical technology challenges for the large-scale deployment of the following biomass-based gasification concepts: Direct Fluidized Bed Gasification (FBG), Entrained Flow Gasification (EFG) and indirect Dual Fluidized Bed Gasification (DFBG). The main content in this report is based on responses from a number of experts in biomass gasification obtained from a questionnaire. The survey was composed of a number of more or less specific questions on technical barriers as to the three gasification concepts considered. For formalising the questionnaire, the concept of Technology Readiness Level (TRL 1-9) was used for grading the level of technical maturity of the different sub-processes within the three generic biomass gasification technologies. For direct fluidized bed gasification (FBG) it is mentioned that the technology is already available at commercial scale as air-blown technology and thus that air-blown FBG gasification may be reckoned a mature technology. The remaining technical challenge is the conversion to operation on oxygen with the final goal of producing chemicals or transport fuels. Tar reduction, in particular, and gas cleaning and upgrading in general are by far the most frequently named technical issues considered problematic. Other important aspects are problems that may occur when operating on low-grade fuels - i.e. low-cost fuels. These problems include bed agglomeration/ash sintering as well as alkali fouling. Even the preparation and feeding of these low-grade fuels tend to be problematic and require further development to be used on a commercial scale. Furthermore, efficient char conversion is mentioned by

Biomass sector review for the Carbon Trust

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-10-26

In great depth. Our review suggested a focus (from a cost-effective carbon reduction point of view) on very small, scale (about 0.2MW) to industrial scale (about 30MW) units generating heat and power. The cost, of carbon in domestic-scale applications was found to be very high. Within combustion processes, heat applications, especially small heat (e.g. around 2MW), have the most attractive and robust plant economics, excluding government incentives. When replacing oil-fired boilers, small heat plant have the most favourable investment returns of all the applications examined (which included large and small CHP, large and small electricity only). The oil price is the main driver of heat plant economics. At our medium crude oil price scenario ($30/bbl), small heat is the only application with a positive IRR (c.5%) for all biomass fuels. At our high oil price scenario ($50/bbl). small heat, plant returns are high enough to attract investment (c.20%). Large heat (around 30MW) and very small heat (around 0.2MW) generate positive returns for all fuels, but are probably too low for investment (i.e. c.10%). The most attractive of the other applications is large CHP, which at $50/bbl has positive returns for all of the key fuels. With current Government incentives, large biomass CHP becomes attractive for investment, generating returns of between 15-20% at $30/bbl. Four main barriers affect all developers. These barriers increase the risk of investing in biomass (thereby increasing the cost of capital), and increase operating costs. Together these reduce the economic viability of biomass developments. The four main barriers are: Market information; Fuel supply risks; Planning; and Policy costs. (UK)

Catalytically supported reduction of emissions from small-scale biomass furnace systems; Katalytisch unterstuetzte Minderung von Emissionen aus Biomasse-Kleinfeuerungsanlagen

Energy Technology Data Exchange (ETDEWEB)

Hartmann, Ingo; Lenz, Volker; Schenker, Marian; Thiel, Christian [DBFZ Deutsches Biomasseforschungszentrum gemeinnuetzige GmbH, Leipzig (Germany); Kraus, Markus; Matthes, Mirjam; Roland, Ulf [Helmholtz-Zentrum fuer Umweltforschung GmbH - UFZ, Leipzig (Germany); Bindig, Rene; Einicke, Wolf-Dietrich [Leipzig Univ. (Germany)

2011-06-29

The increased use of solid biomass in small combustion for generating heat from renewable energy sources is unfortunately associated with increased emissions of airborne pollutants. The reduction is possible on the one hand by the use of high-quality modern furnaces to the latest state of the art. On the other hand, several promising approaches method for retrofitting small-scale furnaces are currently being developed that will allow an effective emission reduction by the subsequent treatment of the exhaust gas. The overview of current available emission control technologies for small-scale biomass combustion plants shows that there is still considerable need for research on the sustainable production of heat from solid biofuels. The amendment to the 1st BImSchV provides a necessary drastic reduction of discharged pollutants from small-scale biomass furnaces. When using the fuel wood in modern central heating boilers the required limits can be met at full load. However, dynamic load changes can cause brief dramatic emission increases even with wood central heating boilers. Firebox and control optimization must contribute in the future to a further reduction of emissions. The typical simple single-room fireplaces like hand-fed wood stoves are suitable under type test conditions to comply the limit values. By contrast, in practical operation, the harmful gas emissions be exceeded without secondary measures normally. The performed experimental investigations show that a reduction of both CO and of organic compounds by catalytic combustion is possible. In addition to developing specially adapted catalysts, it is necessary to provide additional dust separation by combined processes, since conventional catalysts are not suitable for deposition and retention of particulate matter or would lose their activity due to dust accumulation on the active surface, when the catalyst would act as a filter at the same time. To enable sufficiently high reaction temperatures and thus a

Catalytically supported reduction of emissions from small-scale biomass furnace systems; Katalytisch unterstuetzte Minderung von Emissionen aus Biomasse-Kleinfeuerungsanlagen

Energy Technology Data Exchange (ETDEWEB)

Hartmann, Ingo; Lenz, Volker; Schenker, Marian; Thiel, Christian [DBFZ Deutsches Biomasseforschungszentrum gemeinnuetzige GmbH, Leipzig (Germany); Kraus, Markus; Matthes, Mirjam; Roland, Ulf [Helmholtz-Zentrum fuer Umweltforschung GmbH - UFZ, Leipzig (Germany); Bindig, Rene; Einicke, Wolf-Dietrich [Leipzig Univ. (Germany)

2011-06-29

The increased use of solid biomass in small combustion for generating heat from renewable energy sources is unfortunately associated with increased emissions of airborne pollutants. The reduction is possible on the one hand by the use of high-quality modern furnaces to the latest state of the art. On the other hand, several promising approaches method for retrofitting small-scale furnaces are currently being developed that will allow an effective emission reduction by the subsequent treatment of the exhaust gas. The overview of current available emission control technologies for small-scale biomass combustion plants shows that there is still considerable need for research on the sustainable production of heat from solid biofuels. The amendment to the 1st BImSchV provides a necessary drastic reduction of discharged pollutants from small-scale biomass furnaces. When using the fuel wood in modern central heating boilers the required limits can be met at full load. However, dynamic load changes can cause brief dramatic emission increases even with wood central heating boilers. Firebox and control optimization must contribute in the future to a further reduction of emissions. The typical simple single-room fireplaces like hand-fed wood stoves are suitable under type test conditions to comply the limit values. By contrast, in practical operation, the harmful gas emissions be exceeded without secondary measures normally. The performed experimental investigations show that a reduction of both CO and of organic compounds by catalytic combustion is possible. In addition to developing specially adapted catalysts, it is necessary to provide additional dust separation by combined processes, since conventional catalysts are not suitable for deposition and retention of particulate matter or would lose their activity due to dust accumulation on the active surface, when the catalyst would act as a filter at the same time. To enable sufficiently high reaction temperatures and thus a

Gasification technologies for heat and power from biomass

NARCIS (Netherlands)

Beenackers, AACM; Maniatis, K; Kaltschmitt, M; Bridgwater, AV

1997-01-01

A critical review is presented of biomass gasifier systems presently commercially available or under development. Advantages and possible problem areas are discussed in relation to particular applications. Both large and small scale technologies are reviewed. Catalysed by the EC JOULE and AIR

Influences of biomass heat and biochemical energy storages on the land surface fluxes and radiative temperature

Science.gov (United States)

Gu, Lianhong; Meyers, Tilden; Pallardy, Stephen G.; Hanson, Paul J.; Yang, Bai; Heuer, Mark; Hosman, Kevin P.; Liu, Qing; Riggs, Jeffery S.; Sluss, Dan; Wullschleger, Stan D.

2007-01-01

The interest of this study was to develop an initial assessment on the potential importance of biomass heat and biochemical energy storages for land-atmosphere interactions, an issue that has been largely neglected so far. We conducted flux tower observations and model simulations at a temperate deciduous forest site in central Missouri in the summer of 2004. The model used was the comprehensive terrestrial ecosystem Fluxes and Pools Integrated Simulator (FAPIS). We first examined FAPIS performance by testing its predictions with and without the representation of biomass energy storages against measurements of surface energy and CO2 fluxes. We then evaluated the magnitudes and temporal patterns of the biomass energy storages calculated by FAPIS. Finally, the effects of biomass energy storages on land-atmosphere exchanges of sensible and latent heat fluxes and variations of land surface radiative temperature were investigated by contrasting FAPIS simulations with and without these storage terms. We found that with the representation of the two biomass energy storage terms, FAPIS predictions agreed with flux tower measurements fairly well; without the representation, however, FAPIS performance deteriorated for all predicted surface energy flux terms although the effect on the predicted CO2 flux was minimal. In addition, we found that the biomass heat storage and biochemical energy storage had clear diurnal patterns with typical ranges from -50 to 50 and -3 to 20 W m-2, respectively; these typical ranges were exceeded substantially when there were sudden changes in atmospheric conditions. Furthermore, FAPIS simulations without the energy storages produced larger sensible and latent heat fluxes during the day but smaller fluxes (more negative values) at night as compared with simulations with the energy storages. Similarly, without-storage simulations had higher surface radiative temperature during the day but lower radiative temperature at night, indicating that the

AUTOMATIC BIOMASS BOILER WITH AN EXTERNAL THERMOELECTRIC GENERATOR

OpenAIRE

Marian Brázdil; Ladislav Šnajdárek; Petr Kracík; Jirí Pospíšil

2014-01-01

This paper presents the design and test results of an external thermoelectric generator that utilizes the waste heat from a small-scale domestic biomass boiler with nominal rated heat output of 25 kW. The low-temperature Bi2Te3 generator based on thermoelectric modules has the potential to recover waste heat from gas combustion products as effective energy. The small-scale generator is constructed from independent segments. Measurements have shown that up to 11 W of electricity can be generat...

Small-scale CHP Plant based on a 35 kWel Hermetic Four Cylinder Stirling Engine for Biomass Fuels- Development, Technology and Operating Experiences

DEFF Research Database (Denmark)

Obernberger, I.; Carlsen, Henrik; Biedermann, F.

2003-01-01

) process and the Stirling engine process. The ORC process represents an economically interesting technology for small-scale biomass-fired combined heat and power plants in a power range between 400 and 1,500 kWel. A newly developed ORC technology with a nominal electric capacity of 1,000 kW was implemented...... in the biomass CHP plant Lienz (A) in the framework of an EU demonstration project. This plant was put in operation in February 2002. Stirling engines are a promising solution for installations with nominal electric capacities between 10 and 150 kW. A biomass CHP pilot plant based on a 35 kWel-Stirling engine...

Optimal design and operating strategies for a biomass-fueled combined heat and power system with energy storage

DEFF Research Database (Denmark)

Zheng, Yingying; Jenkins, Bryan M.; Kornbluth, Kurt

2018-01-01

An economic linear programming model with a sliding time window was developed to assess designing and scheduling a biomass-fueled combined heat and power system consisting of biomass gasifier, internal combustion engine, heat recovery set, heat-only boiler, producer gas storage and thermal energy......, utility tariff structure and technical and finical performance of the system components. Engine partial load performance was taken into consideration. Sensitivity analyses demonstrate how the optimal BCHP configuration changes with varying demands and utility tariff rates....

Drying and heat decomposition of biomass during the production of biochar

Science.gov (United States)

Lyubov, V. K.; Popova, E. I.

2017-11-01

The process of wood torrefaction provides an opportunity to combine properties of biofuel and steam coal. Different degrees of biofuel heat treating leads to varied outcomes and varied biochar heating value. Therefore, the torrefaction process requires optimal operation that ensures the highest heating value of biochar with the lowest energy loss. In this paper we present the experimental results of drying cycle and thermal decomposition of particles of spruce stem wood and hydrolytic lignin in argon under various temperature conditions and basic material humidity as well as changes in the morphological structure of the biomass and its grain size composition during the torrefaction.

Estimating GHG emission mitigation supply curves of large-scale biomass use on a country level

International Nuclear Information System (INIS)

Dornburg, Veronika; Dam, Jinke van; Faaij, Andre

2007-01-01

This study evaluates the possible influences of a large-scale introduction of biomass material and energy systems and their market volumes on land, material and energy market prices and their feedback to greenhouse gas (GHG) emission mitigation costs. GHG emission mitigation supply curves for large-scale biomass use were compiled using a methodology that combines a bottom-up analysis of biomass applications, biomass cost supply curves and market prices of land, biomaterials and bioenergy carriers. These market prices depend on the scale of biomass use and the market volume of materials and energy carriers and were estimated using own-price elasticities of demand. The methodology was demonstrated for a case study of Poland in the year 2015 applying different scenarios on economic development and trade in Europe. For the key technologies considered, i.e. medium density fibreboard, poly lactic acid, electricity and methanol production, GHG emission mitigation costs increase strongly with the scale of biomass production. Large-scale introduction of biomass use decreases the GHG emission reduction potential at costs below 50 Euro /Mg CO 2eq with about 13-70% depending on the scenario. Biomaterial production accounts for only a small part of this GHG emission reduction potential due to relatively small material markets and the subsequent strong decrease of biomaterial market prices at large scale of production. GHG emission mitigation costs depend strongly on biomass supply curves, own-price elasticity of land and market volumes of bioenergy carriers. The analysis shows that these influences should be taken into account for developing biomass implementations strategies

Estimating the Heat of Formation of Foodstuffs and Biomass

Energy Technology Data Exchange (ETDEWEB)

Burnham, Alan K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2010-11-23

Calorie estimates for expressing the energy content of food are common, however they are inadequate for the purpose of estimating the chemically defined heat of formation of foodstuffs for two reasons. First, they assume utilization factors by the body.1,2,3 Second, they are usually based on average values for their components. The best way to solve this problem would be to measure the heat of combustion of each material of interest. The heat of formation can then be calculated from the elemental composition and the heats of formation of CO2, H2O, and SO2. However, heats of combustion are not always available. Sometimes elemental analysis only is available, or in other cases, a breakdown into protein, carbohydrates, and lipids. A simple way is needed to calculate the heat of formation from various sorts of data commonly available. This report presents improved correlations for relating the heats of combustion and formation to the elemental composition, moisture content, and ash content. The correlations are also able to calculate heats of combustion of carbohydrates, proteins, and lipids individually, including how they depend on elemental composition. The starting point for these correlations are relationships commonly used to estimate the heat of combustion of fossil fuels, and they have been modified slightly to agree better with the ranges of chemical structures found in foodstuffs and biomass.

Current and potential utilisation of biomass energy in Fiji

International Nuclear Information System (INIS)

Prasad, S.

1990-01-01

Energy from biomass accounts for an average of 43% of the primary energy used in developing countries, with some countries totally dependent on biomass for all their energy needs. The most common use for biomass for energy is the provision of heat for cooking and heating; other uses include steam and electricity generation and crop and food drying. Fiji, a developing country, uses energy from wood and coconut wastes for cooking and copra drying. Bagasse from sugar mills is used to generate process steam as well as some 15 MW of electricity, for mill consumption and for sale to the national grid. Other, relatively small scale uses for biomass include the generation of steam and electricity for industry. This paper attempts to quantify the amount of biomass, in its various forms, available in Fiji and assesses the current potential utilisation of biomass for energy in Fiji. (author)

Technoeconomic analysis of a biomass based district heating system. Paper no. IGEC-1-ID01

International Nuclear Information System (INIS)

Zhang, H.; Ugursal, V.I.; Fung, A.

2005-01-01

District energy systems (DES) that produce steam, hot water or chilled water at a central plant and then distribute that energy to buildings in the district for space heating, domestic hot water heating and air conditioning provide opportunities for increasing energy efficiency and reducing greenhouse gas (GHG) emissions. Use of biomass, such as wood, wood byproducts and wastes, fast-growing trees, agricultural crops and waste, in place of conventional fossil fuels to produce the thermal energy needed by a DES, presents further opportunities for reducing green house gas emissions as well as providing rural employment, and local solutions to rural and remote energy needs. In this paper, a technoeconomic analysis of a biomass based DES for a community center in Nova Scotia, Canada is presented. The methodology used to size and design the heating and ventilating system, as well as the biomass based DES is discussed. Annual energy requirement and biomass fuel consumption predictions are presented along with cost estimates. A comparative assessment of the economic feasibility of the system vis-a-vis a conventional oil fired system is conducted. While the results are specific to the particular application, the design and analysis methodology that is presented in the paper can be used for any similar application. (author)

Production of methanol/DME from biomass

Energy Technology Data Exchange (ETDEWEB)

Ahrenfeldt, J.; Birk Henriksen, U.; Muenster-Swendsen, J.; Fink, A.; Roengaard Clausen, L.; Munkholt Christensen, J.; Qin, K.; Lin, W.; Arendt Jensen, P.; Degn Jensen, A.

2011-07-01

In this project the production of DME/methanol from biomass has been investigated. Production of DME/methanol from biomass requires the use of a gasifier to transform the solid fuel to a synthesis gas (syngas) - this syngas can then be catalytically converted to DME/methanol. Two different gasifier types have been investigated in this project: 1) The Two-Stage Gasifier (Viking Gasifier), designed to produce a very clean gas to be used in a gas engine, has been connected to a lab-scale methanol plant, to prove that the gas from the gasifier could be used for methanol production with a minimum of gas cleaning. This was proved by experiments. Thermodynamic computer models of DME and methanol plants based on using the Two-Stage Gasification concept were created to show the potential of such plants. The models showed that the potential biomass to DME/methanol + net electricity energy efficiency was 51-58% (LHV). By using waste heat from the plants for district heating, the total energy efficiencies could reach 87-88% (LHV). 2) A lab-scale electrically heated entrained flow gasifier has been used to gasify wood and straw. Entrained flow gasifiers are today the preferred gasifier type for commercial coal gasification, but little information exists on using these types of gasifiers for biomass gasification. The experiments performed provided quantitative data on product and gas composition as a function of operation conditions. Biomass can be gasified with less oxygen consumption compared to coal. The organic fraction of the biomass that is not converted to gas appears as soot. Thermodynamic computer models of DME and methanol plants based on using entrained flow gasification were created to show the potential of such plants. These models showed that the potential torrefied biomass to DME/methanol + net electricity energy efficiency was 65-71% (LHV). Different routes to produce liquid transport fuels from biomass are possible. They include production of RME (rapeseed oil

A Preliminary Study on Rock Bed Heat Storage from Biomass Combustion for Rice Drying

Science.gov (United States)

Nelwan, L. O.; Wulandani, D.; Subrata, I. D. M.

2018-05-01

One of the main constraints of biomass fuel utilization in a small scale rice drying system is the operating difficulties related to the adjustment of combustion/feeding rate. Use of thermal storage may reduce the problem since combustion operation can be accomplished in a much shorter time and then the use of heat can be regulated by simply adjusting the air flow. An integrated biomass furnace-rock bed thermal storage with a storage volume of 540 L was designed and tested. There were four experiments conducted in this study. Charging was performed within 1-2 hours with a combustion rate of 11.5-15.5 kg/h. In discharging process, the mixing of air passing through the rock bed and ambient air were regulated by valves. Without adjusting the valve during the discharging process, air temperature increased up to 80°C, which is not suitable for rice batch drying process. Charging with sufficiently high combustion rate (14 kg/h) within 1 hour continued by adjusting the valve during discharging process below 60°C increased the discharge-charge time ratio (DCTR) up to 5.33 at average air temperature of 49°C and ambient temperature of 33°C.The efficiency of heat discharging was ranged from 34.5 to 45.8%. From the simulation, as much as 156.8-268.8 kg of rice was able to be dried by the discharging conditions.

Performance Evaluation of a Lithium-Chloride Absorption Refrigeration and an Assessment of Its Suitability for Biomass Waste Heat

Directory of Open Access Journals (Sweden)

Sacha Oberweis

2012-10-01

Full Text Available This paper presents a computer model that will evaluate the performance of a thermo-chemical accumulator. The model is based on operational data such as temperatures and flow rates. The ultimate goal for this model is to estimate the coefficient of performance (COP of this unit when run on hot water from biomass combustion as the heat source. The outputs of the model are verified by comparing the simulation of the actual machine with published experimental data. The computed results for cooling COP are within 10% of the measured data. The simulations are all run for heat load temperatures varying between 80 °C and 110 °C. As expected, simulation results showed an increase in COP with increased heat source temperatures. The results demonstrate that the potential of combined solar and biomass combustion as a heat source for absorption cooling/heating in climates with low solar radiation can be coupled with biomass waste.

Some ecological guidelines for large-scale biomass plantations

Energy Technology Data Exchange (ETDEWEB)

Hoffman, W.; Cook, J.H.; Beyea, J. [National Audubon Society, Tavernier, FL (United States)

1993-12-31

The National Audubon Society sees biomass as an appropriate and necessary source of energy to help replace fossil fuels in the near future, but is concerned that large-scale biomass plantations could displace significant natural vegetation and wildlife habitat, and reduce national and global biodiversity. We support the development of an industry large enough to provide significant portions of our energy budget, but we see a critical need to ensure that plantations are designed and sited in ways that minimize ecological disruption, or even provide environmental benefits. We have been studying the habitat value of intensively managed short-rotation tree plantations. Our results show that these plantations support large populations of some birds, but not all of the species using the surrounding landscape, and indicate that their value as habitat can be increased greatly by including small areas of mature trees within them. We believe short-rotation plantations can benefit regional biodiversity if they can be deployed as buffers for natural forests, or as corridors connecting forest tracts. To realize these benefits, and to avoid habitat degradation, regional biomass plantation complexes (e.g., the plantations supplying all the fuel for a powerplant) need to be planned, sited, and developed as large-scale units in the context of the regional landscape mosaic.

Performance of a pilot-scale, steam-blown, pressurized fluidized bed biomass gasifier

Science.gov (United States)

Sweeney, Daniel Joseph

With the discovery of vast fossil resources, and the subsequent development of the fossil fuel and petrochemical industry, the role of biomass-based products has declined. However, concerns about the finite and decreasing amount of fossil and mineral resources, in addition to health and climate impacts of fossil resource use, have elevated interest in innovative methods for converting renewable biomass resources into products that fit our modern lifestyle. Thermal conversion through gasification is an appealing method for utilizing biomass due to its operability using a wide variety of feedstocks at a wide range of scales, the product has a variety of uses (e.g., transportation fuel production, electricity production, chemicals synthesis), and in many cases, results in significantly lower greenhouse gas emissions. In spite of the advantages of gasification, several technical hurdles have hindered its commercial development. A number of studies have focused on laboratory-scale and atmospheric biomass gasification. However, few studies have reported on pilot-scale, woody biomass gasification under pressurized conditions. The purpose of this research is an assessment of the performance of a pilot-scale, steam-blown, pressurized fluidized bed biomass gasifier. The 200 kWth fluidized bed gasifier is capable of operation using solid feedstocks at feedrates up to 65 lb/hr, bed temperatures up to 1600°F, and pressures up to 8 atm. Gasifier performance was assessed under various temperatures, pressure, and feedstock (untreated woody biomass, dark and medium torrefied biomass) conditions by measuring product gas yield and composition, residue (e.g., tar and char) production, and mass and energy conversion efficiencies. Elevated temperature and pressure, and feedstock pretreatment were shown to have a significant influence on gasifier operability, tar production, carbon conversion, and process efficiency. High-pressure and temperature gasification of dark torrefied biomass

Thermo-economic assessment of externally fired micro-gas turbine fired by natural gas and biomass: Applications in Italy

International Nuclear Information System (INIS)

Pantaleo, A.M.; Camporeale, S.M.; Shah, N.

2013-01-01

Highlights: • A thermo-economic analysis of natural gas/biomass fired microturbine is proposed. • Energy efficiency, capex, opex and electricity revenues trade-offs are assessed. • The optimal biomass energy input is 70% of total CHP consumption. • Industrial/tertiary heat demand and baseload/heat driven operation is assessed. • The main barriers of small scale CHP systems in Italy are overviewed. - Abstract: This paper proposes a thermo-economic assessment of small scale (100 kWe) combined heat and power (CHP) plants fired by natural gas and solid biomass. The focus is on dual fuel gas turbine cycle, where compressed air is heated in a high temperature heat exchanger (HTHE) using the hot gases produced in a biomass furnace, before entering the gas combustion chamber. The hot air expands in the turbine and then feeds the internal pre-heater recuperator, Various biomass/natural gas energy input ratios are modeled, ranging from 100% natural gas to 100% biomass. The research assesses the trade-offs between: (i) lower energy conversion efficiency and higher investment cost of high biomass input rate and (ii) higher primary energy savings and revenues from bio-electricity feed-in tariff in case of high biomass input rate. The influence of fuel mix and biomass furnace temperature on energy conversion efficiencies, primary energy savings and profitability of investments is assessed. The scenarios of industrial vs. tertiary heat demand and baseload vs. heat driven plant operation are also compared. On the basis of the incentives available in Italy for biomass electricity and for high efficiency cogeneration (HEC), the maximum investment profitability is achieved for 70% input biomass percentage. The main barriers of these embedded cogeneration systems in Italy are also discussed

Biomass application for heating primary schools in Portugal

International Nuclear Information System (INIS)

Pires, A.; Cordeiro, M.

2000-01-01

The use of renewable energies for heating the schools, hospitals, public and agricultural buildings and even houses must constitute a principal option instead a second choice. The life quality of the people, in this case the students of primary schools, must be concern for all the people whose working in the energy subject. All the people must be aware that the life quality must be tried by the use of the renewable energies and in this case the biomass. This work pretends to be a good contribution for using of this type of energy. (Author)

A renewable energy scenario for Aalborg Municipality based on low-temperature geothermal heat, wind power and biomass

DEFF Research Database (Denmark)

Østergaard, Poul Alberg; Mathiesen, Brian Vad; Möller, Bernd

2010-01-01

Aalborg Municipality, Denmark, wishes to investigate the possibilities of becoming independent of fossil fuels. This article describes a scenario for supplying Aalborg Municipality’s energy needs through a combination of low-temperature geothermal heat, wind power and biomass. Of particular focus...... in the scenario is how low-temperature geothermal heat may be utilised in district heating (DH) systems. The analyses show that it is possible to cover Aalborg Municipality’s energy needs through the use of locally available sources in combination with significant electricity savings, heat savings, reductions...... in industrial fuel use and savings and fuel-substitutions in the transport sector. With biomass resources being finite, the two marginal energy resources in Aalborg are geothermal heat and wind power. If geothermal heat is utilised more, wind power may be limited and vice versa. The system still relies...

Large-scale solar heat

Energy Technology Data Exchange (ETDEWEB)

Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics

1998-12-31

In this project a large domestic solar heating system was built and a solar district heating system was modelled and simulated. Objectives were to improve the performance and reduce costs of a large-scale solar heating system. As a result of the project the benefit/cost ratio can be increased by 40 % through dimensioning and optimising the system at the designing stage. (orig.)

Power/heat production from biomass in Finland - Two modern Finnish examples

International Nuclear Information System (INIS)

Aeijaelae, M.

1997-01-01

According to this conference paper, Finland is a leading country in the utilization of biomass fuels for power and heat production. One reason is that peat and wood are the only indigenous fuels available in Finland. Other reasons are the strong forest industry and the widely adopted combined heat and power (CHP) production. CHP production is typical of process industry and municipal district heating. The most common boiler type in modern CHP plants is the fluidized bed type. District heating is the cheapest heating in municipalities with a few thousand inhabitants. Electric heating dominates in sparsely populated regions. CHP becomes attractive for populations of more than ten thousand. Two examples are described: (1) Rauhalahti Power Plant produces 140 MW of district heat, 65 MW of industrial steam and 87 MW of electricity. (2) Kuusamo Power Plant produces 6.1 MW electric energy and 17.6 MW district heat; its unique feature is the utilization of the bed mixing dryer for drying of the fuel prior to combustion, this dryer being the first of its kind in the world. 1 figure

Modeling the influence of potassium content and heating rate on biomass pyrolysis

DEFF Research Database (Denmark)

Trubetskaya, Anna; Surup, Gerrit; Shapiro, Alexander

2017-01-01

This study presents a combined kinetic and particle model that describes the effect of potassium and heating rate during the fast pyrolysis of woody and herbaceous biomass. The model calculates the mass loss rate, over a wide range of operating conditions relevant to suspension firing...

Performance of entrained flow and fluidised bed biomass gasifiers on different scales

International Nuclear Information System (INIS)

Tremel, Alexander; Becherer, Dominik; Fendt, Sebastian; Gaderer, Matthias; Spliethoff, Hartmut

2013-01-01

Highlights: ► Gasification of biomass in fluidised bed and entrained flow reactors is modelled. ► The systems are evaluated for a thermal input from 10 MW to 500 MW. ► Special attention is given to the preconditioning methods for biomass. ► Fluidised bed and entrained flow gasifiers are compared in terms of efficiency and costs. - Abstract: This biomass gasification process study compares the energetic and economic efficiencies of a dual fluidised bed and an oxygen-blown entrained flow gasifier from 10 MW th to 500 MW th . While fluidised bed gasification became the most applied technology for biomass in small and medium scale facilities, entrained flow gasification technology is still used exclusively for industrial scale coal gasification. Therefore, it is analysed whether and for which capacity the entrained flow technology is an energetically and economically efficient option for the thermo-chemical conversion of biomass. Special attention is given to the pre-conditioning methods for biomass to enable the application in an entrained flow gasifier. Process chains are selected for the two gasifier types and subsequently transformed to simulation models. The simulation results show that the performance of both gasifier types is similar for the production of a pressurised product gas (2.5 MPa). The cold gas efficiency of the fluidised bed is 76–79% and about 0.5–2 percentage points higher than for the entrained flow reactor. The net efficiencies of both technologies are similar and between 64% and 71% depending on scale. The auxiliary power consumption of the entrained flow reactor is caused mainly by the air separation unit, the oxygen compression, and the fuel pulverisation, whereas the fluidised bed requires additional power mainly for gas compression. The costs for the product gas are determined as between €4.2 cent/kWh (500 MW th ) and €7.4 cent/kWh (10 MW th ) in the economic analysis of both technologies. The study indicates that the

The exploitation of biomass for building space heating in Greece: Energy, environmental and economic considerations

International Nuclear Information System (INIS)

Michopoulos, A.; Skoulou, V.; Voulgari, V.; Tsikaloudaki, A.; Kyriakis, N.A.

2014-01-01

Highlights: • The oil substitution with biomass residues for heating buildings is examined. • Primary energy consumption from biomass results increased by 3–4% as compared to diesel oil. • CO 2 and SO 2 emissions are significantly higher with biomass than with diesel oil. • The examined substitution is economically attractive for the final consumers. - Abstract: The exploitation of forest and agricultural biomass residues for energy production may offer significant advantages to the energy policy of the relevant country, but it strongly depends on a number of financial, technological and political factors. The work in hand focuses on the investigation of the energy, environmental and financial benefits, resulting from the exploitation of forest and agricultural biomass residues, fully substituting the conventional fuel (diesel oil) for building space heating in Greece. For this investigation, the energy needs of a representative building are determined using the EnergyPlus software, assuming that the building is located across the various climate zones of Greece. Based on the resulting thermal energy needs, the primary energy consumption and the corresponding emissions are determined, while an elementary fiscal analysis is also performed. The results show that significant financial benefits for the end-user are associated with the substitution examined, even though increased emissions and primary energy consumption have been derived

Allometric Scaling and Resource Limitations Model of Total Aboveground Biomass in Forest Stands: Site-scale Test of Model

Science.gov (United States)

CHOI, S.; Shi, Y.; Ni, X.; Simard, M.; Myneni, R. B.

2013-12-01

Sparseness in in-situ observations has precluded the spatially explicit and accurate mapping of forest biomass. The need for large-scale maps has raised various approaches implementing conjugations between forest biomass and geospatial predictors such as climate, forest type, soil property, and topography. Despite the improved modeling techniques (e.g., machine learning and spatial statistics), a common limitation is that biophysical mechanisms governing tree growth are neglected in these black-box type models. The absence of a priori knowledge may lead to false interpretation of modeled results or unexplainable shifts in outputs due to the inconsistent training samples or study sites. Here, we present a gray-box approach combining known biophysical processes and geospatial predictors through parametric optimizations (inversion of reference measures). Total aboveground biomass in forest stands is estimated by incorporating the Forest Inventory and Analysis (FIA) and Parameter-elevation Regressions on Independent Slopes Model (PRISM). Two main premises of this research are: (a) The Allometric Scaling and Resource Limitations (ASRL) theory can provide a relationship between tree geometry and local resource availability constrained by environmental conditions; and (b) The zeroth order theory (size-frequency distribution) can expand individual tree allometry into total aboveground biomass at the forest stand level. In addition to the FIA estimates, two reference maps from the National Biomass and Carbon Dataset (NBCD) and U.S. Forest Service (USFS) were produced to evaluate the model. This research focuses on a site-scale test of the biomass model to explore the robustness of predictors, and to potentially improve models using additional geospatial predictors such as climatic variables, vegetation indices, soil properties, and lidar-/radar-derived altimetry products (or existing forest canopy height maps). As results, the optimized ASRL estimates satisfactorily

Greenhouse gas and energy analysis of substitute natural gas from biomass for space heat

International Nuclear Information System (INIS)

Pucker, Johanna; Zwart, Robin; Jungmeier, Gerfried

2012-01-01

In this paper, the greenhouse gas and energy balances of the production and use for space heating of substitute natural gas from biomass (bio-SNG) for space heat are analysed. These balances are compared to the use of natural gas and solid biomass as wood chips to provide the same service. The reduction of the greenhouse gas emissions (CO 2 -eq.) – carbon dioxide, methane and nitrous oxide – and of the fossil primary energy use is investigated in a life cycle assessment (LCA). This assessment was performed for nine systems for bio-SNG; three types of gasification technologies (O 2 -blown entrained flow, O 2 -blown circulating fluidised bed and air–steam indirect gasification) with three different types of feedstock (forest residues, miscanthus and short rotation forestry). The greenhouse gas analysis shows that forest residues using the air–steam indirect gasification technology result in the lowest greenhouse gas emissions (in CO 2 -eq. 32 kg MWh −1 of heat output). This combination results in 80% reduction of greenhouse gas emissions when compared to natural gas and a 29% reduction of greenhouse gases if the forest residues were converted to wood chips and combusted. The gasification technologies O 2 -blown entrained flow and O 2 -blown circulating fluidised bed gasification have higher greenhouse gas emissions that range between in CO 2 -eq. 41 to 75 kg MWh −1 of heat output depending on the feedstock. When comparing feedstocks in the bio-SNG systems, miscanthus had the highest greenhouse gas emissions bio-SNG systems producing in CO 2 -eq. 57–75 kg MWh −1 of heat output. Energy analysis shows that the total primary energy use is higher for bio-SNG systems (1.59–2.13 MWh MWh −1 of heat output) than for the reference systems (in 1.37–1.51 MWh MWh −1 of heat output). However, with bio-SNG the fossil primary energy consumption is reduced compared to natural gas. For example, fossil primary energy use is reduced by 92% when air�

Insight on invasions and resilience derived from spatiotemporal discontinuities of biomass at local and regional scales

Science.gov (United States)

Angeler, David G.; Allen, Criag R.; Johnson, Richard K.

2012-01-01

Understanding the social and ecological consequences of species invasions is complicated by nonlinearities in processes, and differences in process and structure as scale is changed. Here we use discontinuity analyses to investigate nonlinear patterns in the distribution of biomass of an invasive nuisance species that could indicate scale-specific organization. We analyze biomass patterns in the flagellate Gonyostomum semen (Raphidophyta) in 75 boreal lakes during an 11-year period (1997-2007). With simulations using a unimodal null model and cluster analysis, we identified regional groupings of lakes based on their biomass patterns. We evaluated the variability of membership of individual lakes in regional biomass groups. Temporal trends in local and regional discontinuity patterns were analyzed using regressions and correlations with environmental variables that characterize nutrient conditions, acidity status, temperature variability, and water clarity. Regionally, there was a significant increase in the number of biomass groups over time, indicative of an increased number of scales at which algal biomass organizes across lakes. This increased complexity correlated with the invasion history of G. semen and broad-scale environmental change (recovery from acidification). Locally, no consistent patterns of lake membership to regional biomass groups were observed, and correlations with environmental variables were lake specific. The increased complexity of regional biomass patterns suggests that processes that act within or between scales reinforce the presence of G. semen and its potential to develop high-biomass blooms in boreal lakes. Emergent regional patterns combined with locally stochastic dynamics suggest a bleak future for managing G. semen, and more generally why invasive species can be ecologically successful.

Full-scale and time-scale heating experiments at Stripa: preliminary results

International Nuclear Information System (INIS)

Cook, N.G.W.; Hood, Michael; California Univ., Berkeley

1978-01-01

Two full-scale heating experiments and a time-scale heating experiment have recently been started in granite 340 meters below surface. The purpose of the full-scale heating experiments is to assess the near-field effects of thermal loading for the design of an underground repository of nuclear wastes. That of the time-scale heating experiments is to obtain field data of the interaction between heaters and its effect on the rock mass during a period of about two years, which corresponds to about twenty years of full-scale operation. Geological features of the rock around each experiment have been mapped carefully, and temperatures, stresses and displacements induced in the rock by heating have been calculated in advance of the experiments. Some 800 different measurements are recorded at frequent intervals by a computer system situated underground. These data can be compared at any time with predictions made earlier on video display units underground

The use of biomass for energy in Sweden. Critical factors and lessons learned

International Nuclear Information System (INIS)

Johansson, Bengt; Boerjesson, Paal; Ericsson, Karin; Nilsson, Lars J.; Svenningsson, Per

2002-08-01

In this report the development of Swedish biomass use during recent decades is discussed. The relations between biomass supply, biomass demand and various policy initiatives are explored. The objectives are to discuss the most important factors affecting the biomass development and to establish which factors are specific for Swedish conditions and also to identify general factors that are relevant in assessing the possibility of expanding biomass use in different contexts. The focus is on the use of biomass for heat and electricity production. Biomass contributed 14% to the Swedish energy supply in 1999. The major fraction of Swedish biomass is used within the forest industry (63%) and in district heating systems (23%). The remaining fraction is used in small-scale boilers in one- and two family dwellings. Between 1990 and 1999 Swedish bioenergy use (including waste and peat) increased by 44%. During the same period there has been a fourfold increase in the district heating systems. By-products from forestry and the Swedish forest industry dominate the supply of biomass in Sweden, but the importation of biomass increased significantly during the 1990s. A number of factors of various kinds have interacted to bring about the increased use of biomass in Sweden during the past twenty years. These factors can be divided into three categories: structure, policies and actors. The existence of a major forest industry and well-developed district heating systems has enabled a rapid response to strong and standing policy commitments to biomass. The reformation of the taxation system, with the introduction of a high carbon tax on fossil fuels, has led to significantly improved competitiveness for biomass when used for heating purposes.

Development of a new steady state zero-dimensional simulation model for woody biomass gasification in a full scale plant

International Nuclear Information System (INIS)

Formica, Marco; Frigo, Stefano; Gabbrielli, Roberto

2016-01-01

Highlights: • A simulation model with Aspen Plus is created for a full scale biomass gasification plant. • Test results, equipment data and control logics are considered in the simulation model. • The simulation results are in agreement with the experimental data. • The gasifying air temperature affects largely the energy performance of the gasification plant. • Increasing the equivalent ratio implies a strong reduction of the gasification efficiency. - Abstract: A new steady state zero-dimensional simulation model for a full-scale woody biomass gasification plant with fixed-bed downdraft gasifier has been developed using Aspen Plus®. The model includes the technical characteristics of all the components (gasifier, cyclone, exchangers, piping, etc.) of the plant and works in accordance with its actual main control logics. Simulation results accord with those obtained during an extensive experimental activity. After the model validation, the influence of operating parameters such as the equivalent ratio, the biomass moisture content and the gasifying air temperature on syngas composition have been analyzed in order to assess the operative behavior and the energy performance of the experimental plant. By recovering the sensible heat of the syngas at the outlet of the gasifier, it is possible to obtain higher values of the gasifying air temperature and an improvement of the overall gasification performances.

Biomass pyrolysis and combustion integral and differential reaction heats with temperatures using thermogravimetric analysis/differential scanning calorimetry.

Science.gov (United States)

Shen, Jiacheng; Igathinathane, C; Yu, Manlu; Pothula, Anand Kumar

2015-06-01

Integral reaction heats of switchgrass, big bluestem, and corn stalks were determined using thermogravimetric analysis/differential scanning calorimetry (TGA/DSC). Iso-conversion differential reaction heats using TGA/DSC pyrolysis and combustion of biomass were not available, despite reports available on heats required and released. A concept of iso-conversion differential reaction heats was used to determine the differential reaction heats of each thermal characteristics segment of these materials. Results showed that the integral reaction heats were endothermic from 30 to 700°C for pyrolysis of switchgrass and big bluestem, but they were exothermic for corn stalks prior to 587°C. However, the integral reaction heats for combustion of the materials followed an endothermic to exothermic transition. The differential reaction heats of switchgrass pyrolysis were predominantly endothermic in the fraction of mass loss (0.0536-0.975), and were exothermic for corn stalks (0.0885-0.850) and big bluestem (0.736-0.919). Study results provided better insight into biomass thermal mechanism. Published by Elsevier Ltd.

Integration of biomass into urban energy systems for heat and power. Part II: Sensitivity assessment of main techno-economic factors

International Nuclear Information System (INIS)

Pantaleo, Antonio M.; Giarola, Sara; Bauen, Ausilio; Shah, Nilay

2014-01-01

Highlights: • Application of a MILP tool for optimal sizing and location of heating and CHP plants to serve residential energy demand. • Trade-offs between local vs centralized heat generation, district heating vs natural gas distribution systems. • Assessment of the key factors influencing the use of biomass and district heating in residential areas. - Abstract: The paper presents the application of a mixed integer linear programming (MILP) methodology to optimize multi-biomass and natural gas supply chain strategic design for heat and power generation in urban areas. The focus is on spatial and temporal allocation of biomass supply, storage, processing, transport and energy conversion (heat and CHP) to match the heat demand of residential end users. The main aim lies on the assessment of the trade-offs between centralized district heating plants and local heat generation systems, and on the decoupling of the biomass processing and biofuel energy conversion steps. After a brief description of the methodology, which is presented in detail in Part I of the research, an application to a generic urban area is proposed. Moreover, the influence of energy demand typologies (urban areas energy density, heat consumption patterns, buildings energy efficiency levels, baseline energy costs and available infrastructures) and specific constraints of urban areas (transport logistics, air emission levels, space availability) on the selection of optimal bioenergy pathways for heat and power is assessed, by means of sensitivity analysis. On the basis of these results, broad considerations about the key factors influencing the use of bioenergy into urban energy systems are proposed. Potential further applications of this model are also described, together with main barriers for development of bioenergy routes for urban areas

Biomass Deconstruction and Recalcitrance

DEFF Research Database (Denmark)

Zhang, Heng

This thesis is about the use of an agricultural residue as a feedstock for fermentable sugars to be used for second generation (2G) bioethanol. The main focus of this thesis work is upon the recalcitrance of different anatomical fractions of wheat straw. Biomass recalcitrance is a collective...... of lignocellulosic biomass’ degradability, a high throughput screening (HTS) platform was developed for combined thermochemical pretreatment and enzymatic degradation in Copenhagen laboratory during this thesis work. The platform integrates an automatized biomass grinding and dispensing system, a pressurized heating...... system, a plate incubator and a high performance liquid chromatography (HPLC) system. In comparison with the reported HTS platforms, the Copenhagen platform is featured by the fully automatic biomass sample preparation system, the bench-scale hydrothermal pretreatment setup, and precise sugar measurement...

Simulating Biomass Fast Pyrolysis at the Single Particle Scale

Energy Technology Data Exchange (ETDEWEB)

Ciesielski, Peter [National Renewable Energy Laboratory (NREL); Wiggins, Gavin [ORNL; Daw, C Stuart [ORNL; Jakes, Joseph E. [U.S. Forest Service, Forest Products Laboratory, Madison, Wisconsin, USA

2017-07-01

Simulating fast pyrolysis at the scale of single particles allows for the investigation of the impacts of feedstock-specific parameters such as particle size, shape, and species of origin. For this reason particle-scale modeling has emerged as an important tool for understanding how variations in feedstock properties affect the outcomes of pyrolysis processes. The origins of feedstock properties are largely dictated by the composition and hierarchical structure of biomass, from the microstructural porosity to the external morphology of milled particles. These properties may be accounted for in simulations of fast pyrolysis by several different computational approaches depending on the level of structural and chemical complexity included in the model. The predictive utility of particle-scale simulations of fast pyrolysis can still be enhanced substantially by advancements in several areas. Most notably, considerable progress would be facilitated by the development of pyrolysis kinetic schemes that are decoupled from transport phenomena, predict product evolution from whole-biomass with increased chemical speciation, and are still tractable with present-day computational resources.

Emerging large-scale solar heating applications

International Nuclear Information System (INIS)

Wong, W.P.; McClung, J.L.

2009-01-01

Currently the market for solar heating applications in Canada is dominated by outdoor swimming pool heating, make-up air pre-heating and domestic water heating in homes, commercial and institutional buildings. All of these involve relatively small systems, except for a few air pre-heating systems on very large buildings. Together these applications make up well over 90% of the solar thermal collectors installed in Canada during 2007. These three applications, along with the recent re-emergence of large-scale concentrated solar thermal for generating electricity, also dominate the world markets. This paper examines some emerging markets for large scale solar heating applications, with a focus on the Canadian climate and market. (author)

Emerging large-scale solar heating applications

Energy Technology Data Exchange (ETDEWEB)

Wong, W.P.; McClung, J.L. [Science Applications International Corporation (SAIC Canada), Ottawa, Ontario (Canada)

2009-07-01

Currently the market for solar heating applications in Canada is dominated by outdoor swimming pool heating, make-up air pre-heating and domestic water heating in homes, commercial and institutional buildings. All of these involve relatively small systems, except for a few air pre-heating systems on very large buildings. Together these applications make up well over 90% of the solar thermal collectors installed in Canada during 2007. These three applications, along with the recent re-emergence of large-scale concentrated solar thermal for generating electricity, also dominate the world markets. This paper examines some emerging markets for large scale solar heating applications, with a focus on the Canadian climate and market. (author)

Characterization of biomass producer gas as fuel for stationary gas engines in combined heat and power production

DEFF Research Database (Denmark)

Ahrenfeldt, Jesper

2008-01-01

The aim of this project has been the characterization of biomass producer gas as a fuel for stationary gas engines in heat and power production. More than 3200 hours of gas engine operation, with producer gas as fuel, has been conducted at the biomass gasification combined heat and power (CHP...... different measuring methods. Likewise, no particles were detected in the gas. Considerable amounts of NH3 were measured in the produced gas.An analysis of engine operation at varying load has been carried out. Standard emissions, load and efficiency have been measured at varying operating conditions ranging...... from 50% to 90% load. Biomass producer gas is an excellent lean burn engine fuel: Operation of a natural aspirated engine has been achieved for 1.2...

Torrefaction of biomass for power production

DEFF Research Database (Denmark)

Saleh, Suriyati Binti

In order to increase the share of biomass for sustainable energy production, it will be an advantage to utilize fuels as straw, wood and waste on large suspension fired boilers. On a European scale, currently large straw resources are available that are not fully utilized for energy production...... rates, relatively low superheater temperatures have to be applied, which in turn lower the power efficiency. The idea for this Ph.D. project is to develop a biomass pretreatment method that could provide the heating value of the fuel for the boiler, but in a way such that the fuel is easily pulverized.......D. thesis focus on the following subjects: 1) the development of experimental procedures for a novel laboratory scale reactor (simultaneous torrefaction and grinding) and a study on the torrefaction of straw and wood; 2) study the influence of biomass chemical properties such as ash content, ash composition...

Use of biomass for clean and efficient production of heat and power. Phase 2

Energy Technology Data Exchange (ETDEWEB)

Glarborg, P.; Lans, R. van der; Frandsen, J.B.F.; Johnsson, J.E.; Jensen, A.; Kiil, S.; Dam-Johansen, K.

2001-03-01

The present EFP98 project is the second phase of a long-term, strategic research project, the aim of which is to facilitate the use of significant amounts of biomass in the production of power and heat. The project deals with combustion and emission issues related to the use of biomass, specifically combustion of straw on a grate and wet flue gas desulphurization. A mathematical model for combustion of straw on a grate is developed as a tool to improve the understanding of this process. The model includes heat transfer to and in the bed as well as pyrolysis and char oxidation. To verify the model and to obtain a better understanding of fixed-bed straw combustion, a number of bench-scale laboratory experiments have been conducted at TNO in Holland. Predicted combustion rates and bed temperatures were in fairly good agreement with experimental fixed-bed data. A parameter analysis has identified the sensitivity of modeling predictions towards important parameters in the model. Measuring programs on straw firing have been conducted at Enstedvaerket and Masnedoe. Measuring results include gas temperature and gas composition (O{sub 2}, CO{sub 2}, CO. SO{sub 2}, NO) from different positions in the boiler. Data from Masnedoe include also results from co-firing of straw with other biomass fuels (25-35%). The results indicate that co-firing in the quantities does not significantly affect emissions. Nitrogen oxides emissions from Masnedoevaerket were found to be significantly higher than those of Ensted. The work on wet flue gas desulphurization on aimed to provide the information necessary to optimize and further develop the process. The main focus was fuel and sorbent flexibility, use of the waste product from the semi-dry FGD process as a sorbent in wet FGD, and ways of optimizing the Wet FGD process with respect to a high degree of desulphurization, a low content of residual limestone in the gypsum and a continuous steady state operation of the FGD plant. Laboratory

Feasibility of Biomass Biodrying for Gasification Process

Science.gov (United States)

Hamidian, Arash

An important challenge of biomass gasification is the limitation of feedstock quality especially the moisture content, which plays a significant role on the performance of gasification process. Gasification requires low moisture levels (20% and less) and several reports have emphasized on the moisture as a typical problem while gasifying biomass. Moisture affects overall reaction rates in the gasifiers as a result of temperature drop and ultimately increases tar content, decreases gas yield, changes the composition of produced gas and affects the efficiency. Therefore, it is mandatory to pre-treat the biomass before gasification and reduce the moisture content to the suitable and economic level. The well-known solutions are either natural drying (not practical for commercial plants) or conventional drying technologies (have high operating costs). Biodrying is an alternative process, which uses both convective air and heat of biological reactions as a source of energy, to reduce the moisture. In the biodrying reactor heat is generated from exothermic decomposition of organic fraction of biomass and that is why the process is called "self-heating process". Employing such technology for drying biomass at pre-treatment units of gasification process returns several economic and environmental advantages to mills. In Europe, municipal waste treatment (MSW) plants use the biodrying at commercial scale to degrade a part of the biodegradable fraction of waste to generate heat and reduce the moisture content for high quality SRF (Solid Recovered Fuel) production. In Italy, wine industry is seeking to develop biodrying for energy recovery of grape wastes after fermentation and distillation, which returns economic benefits to the industry. In Canada, the development of biodrying technology for pulp and paper industry was started at Ecole polytechnique de Montreal as an option for sludge management solution. Therefore, batch biodrying reactor was successfully developed in 2004

Evaluation of biogas and syngas as energy vectors for heat and power generation using lignocellulosic biomass as raw material

Directory of Open Access Journals (Sweden)

Juan Camilo Solarte-Toro

2018-05-01

Full Text Available The use of nonrenewable energy sources to provide the worldwide energy needs has caused different problems such as global warming, water pollution, and smog production. In this sense, lignocellulosic biomass has been postulated as a renewable energy source able to produce energy carriers that can cover this energy demand. Biogas and syngas are two energy vectors that have been suggested to generate heat and power through their use in cogeneration systems. Therefore, the aim of this review is to develop a comparison between these energy vectors considering their main features based on literature reports. In addition, a techno-economic and energy assessment of the heat and power generation using these vectors as energy sources is performed. If lignocellulosic biomass is used as raw material, biogas is more commonly used for cogeneration purposes than syngas. However, syngas from biomass gasification has a great potential to be employed as a chemical platform in the production of value-added products. Moreover, the investment costs to generate heat and power from lignocellulosic materials using the anaerobic digestion technology are higher than those using the gasification technology. As a conclusion, it was evidenced that upgraded biogas has a higher potential to produce heat and power than syngas. Nevertheless, the implementation of both energy vectors into the energy market is important to cover the increasing worldwide energy demand.How to cite: Solarte-Toro JC, Chacón-Pérez Y, Cardona-Alzate CA. Evaluation of biogas and syngas as energy vectors for heat and power generation using lignocellulosic biomass as raw material. Electron J Biotechnol 2018:33. https://doi.org/10.1016/j.ejbt.2018.03.005 Keywords: Anaerobic digestion, Biogas power generation, Biomass gasification, Biomethane, Energy sources, Energy vectors, Heat generation, Lignocellulosic energy production, Power generation, Renewable energy, Syngas production

Analysis of Competitiveness and Support Instruments for Heat and Electricity Production from Wood Biomass in Latvia

Science.gov (United States)

Klavs, G.; Kudrenickis, I.; Kundzina, A.

2012-01-01

Utilisation of renewable energy sources is one of the key factors in a search for efficient ways of reducing the emissions of greenhouse gases and improving the energy supply security. So far, the district heating supply in Latvia has been based on natural gas, with the wood fuel playing a minor role; the same is true for decentralised combined heat-power (CHP) production. The paper describes a method for evaluation of the economic feasibility of heat and electricity production from wood biomass under the competition between different fuel types and taking into account the electricity market. For the simulation, a cost estimation model is applied. The results demonstrate that wood biomass can successfully be utilised for competitive heat production by boiler houses, while for electricity production by CHP utilities it cannot compete on the market (even despite the low prices on wood biomass fuel) unless particular financial support instruments are applied. The authors evaluate the necessary support level and the impact of two main support instruments - the investment subsidies and the feed-in tariff - on the economic viability of wood-fuelled CHP plants, and show that the feed-in tariff could be considered as an instrument strongly affecting the competitiveness of such type CHP. Regarding the feed-in tariff determination, a compromise should be found between the economy-dictated requirement to develop CHP projects concerning capacities above 5 MWel - on the one hand, and the relatively small heat loads in many Latvian towns - on the other.

Biomass energy conversion: conventional and advanced technologies

Energy Technology Data Exchange (ETDEWEB)

Young, B C; Hauserman, W B [Energy and Environmental Research Center, University of North Dakota, Grand Forks, ND (United States)

1995-12-01

Increasing interest in biomass energy conversion in recent years has focused attention on enhancing the efficiency of technologies converting biomass fuels into heat and power, their capital and operating costs and their environmental emissions. Conventional combustion systems, such as fixed-bed or grate units and entrainment units, deliver lower efficiencies (<25%) than modem coal-fired combustors (30-35%). The gasification of biomass will improve energy conversion efficiency and yield products useful for heat and power generation and chemical synthesis. Advanced biomass gasification technologies using pressurized fluidized-bed systems, including those incorporating hot-gas clean-up for feeding gas turbines or fuel cells, are being demonstrated. However, many biomass gasification processes are derivatives of coal gasification technologies and do not exploit the unique properties of biomass. This paper examines some existing and upcoming technologies for converting biomass into electric power or heat. Small-scale 1-30 MWe units are emphasized, but brief reference is made to larger and smaller systems, including those that bum coal-biomass mixtures and gasifiers that feed pilot-fuelled diesel engines. Promising advanced systems, such as a biomass integrated gasifier/gas turbine (BIG/GT) with combined-cycle operation and a biomass gasifier coupled to a fuel cell, giving cycle efficiencies approaching 50% are also described. These advanced gasifiers, typically fluid-bed designs, may be pressurized and can use a wide variety of biomass materials to generate electricity, process steam and chemical products such as methanol. Low-cost, disposable catalysts are becoming available for hot-gas clean-up (enhanced gas composition) for turbine and fuel cell systems. The advantages, limitations and relative costs of various biomass gasifier systems are briefly discussed. The paper identifies the best known biomass power projects and includes some information on proposed and

Biomass energy conversion: conventional and advanced technologies

International Nuclear Information System (INIS)

Young, B.C.; Hauserman, W.B.

1995-01-01

Increasing interest in biomass energy conversion in recent years has focused attention on enhancing the efficiency of technologies converting biomass fuels into heat and power, their capital and operating costs and their environmental emissions. Conventional combustion systems, such as fixed-bed or grate units and entrainment units, deliver lower efficiencies (<25%) than modem coal-fired combustors (30-35%). The gasification of biomass will improve energy conversion efficiency and yield products useful for heat and power generation and chemical synthesis. Advanced biomass gasification technologies using pressurized fluidized-bed systems, including those incorporating hot-gas clean-up for feeding gas turbines or fuel cells, are being demonstrated. However, many biomass gasification processes are derivatives of coal gasification technologies and do not exploit the unique properties of biomass. This paper examines some existing and upcoming technologies for converting biomass into electric power or heat. Small-scale 1-30 MWe units are emphasized, but brief reference is made to larger and smaller systems, including those that bum coal-biomass mixtures and gasifiers that feed pilot-fuelled diesel engines. Promising advanced systems, such as a biomass integrated gasifier/gas turbine (BIG/GT) with combined-cycle operation and a biomass gasifier coupled to a fuel cell, giving cycle efficiencies approaching 50% are also described. These advanced gasifiers, typically fluid-bed designs, may be pressurized and can use a wide variety of biomass materials to generate electricity, process steam and chemical products such as methanol. Low-cost, disposable catalysts are becoming available for hot-gas clean-up (enhanced gas composition) for turbine and fuel cell systems. The advantages, limitations and relative costs of various biomass gasifier systems are briefly discussed. The paper identifies the best known biomass power projects and includes some information on proposed and

Economic evaluation of externally fired gas turbine cycles for small-scale biomass cogeneration

Energy Technology Data Exchange (ETDEWEB)

Anheden, Marie [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

2001-01-01

In this conceptual study, externally fired gas turbine (EFGT) cycles in combination with a biomass-fueled, atmospheric circulating fluidized bed (CFB) furnace are investigated for small scale heat and power production ({approx} 8 MW fuel input). Three cycle configurations are considered: closed cycle, with nitrogen, helium, and a helium/carbon dioxide mixture as working fluids; open cycle operating in parallel to the CFB system; and open cycle with a series connection to the CFB system. Intercooling, postcooling, and recuperation are employed with the goal of maximizing efficiency. Aside from a thermodynamic performance analysis, the study includes an economic analysis of both the closed and open externally fired gas turbine configurations, and comparisons are made with existing and emerging alternatives for small-scale biomass cogeneration. Simulation results show that thermodynamic performance varies slightly between the different configurations and working fluids, with electrical efficiencies of 31-38% (LHV) and total efficiency of 85-106% (LHV). The economic evaluation shows that the turbomachinery and the CFB furnace dominate the total plant cost, with each contributing about 1/3 of the total installed equipment cost. The specific capital cost for installation in Sweden in 1998 currency is calculated as 26-31 kSEK/kW{sub e} which is equivalent to 3 200-3 900 USD/kW{sub e} or 2 700-3 300 EUR/kW{sub e} .The cost of electricity, COE, is estimated to 590-670 SEK/MWh{sub e} (equivalent to 73-84 USD/MWh{sub e} or 62-71 EUR/MWh{sub e}) for 4 000 full load hours per year in a cogeneration application. Comparing the economic results for the externally fired gas turbine cycles in a slightly larger scale (40-50 MW{sub f}) to the economics of conventional biomass fired steam turbine cycles shows that the cost of electricity for the two plant configurations are roughly the same with a COE of 300-350 SEK/MWh{sub e}. It is believed that the economic performance of the EFGT

Transportation fuel production from gasified biomass integrated with a pulp and paper mill – Part A: Heat integration and system performance

International Nuclear Information System (INIS)

Isaksson, Johan; Jansson, Mikael; Åsblad, Anders; Berntsson, Thore

2016-01-01

Production of transportation fuels from biorefineries via biomass gasification has been suggested as a way of introducing renewable alternatives in the transportation system with an aim to reduce greenhouse gas emissions to the atmosphere. By co-locating gasification-based processes within heat demanding industries, excess heat from the gasification process can replace fossil or renewable fuels. The objective of this study was to compare the heat integration potential of four different gasification-based biorefinery concepts with a chemical pulp and paper mill. The results showed that the choice of end-product which was either methanol, Fischer-Tropsch crude, synthetic natural gas or electricity, can have significant impact on the heat integration potential with a pulp and paper mill and that the heat saving measures implemented in the mill in connection to integration of a gasification process can increase the biomass resource efficiency by up to 3%-points. Heat saving measures can reduce the necessary biomass input to the biorefinery by 50% if the sizing constraint is to replace the bark boiler with excess heat from the biorefinery. A large integrated gasification process with excess steam utilisation in a condensing turbine was beneficial only if grid electricity is produced at below 30% electrical efficiency. - Highlights: • Biomass gasification integrated with a pulp and paper mill. • Different sizing constraints of integrated biofuel production. • The biofuel product largely influence the heat integration potential. • An oversized gasifier for increased power production could be favourable.

Greenhouse gas and energy analysis of substitute natural gas from biomass for space heat

Energy Technology Data Exchange (ETDEWEB)

Pucker, J.; Jungmeier, G. [JOANNEUM RESEARCH Forschungsgesellschaft mbH, RESOURCES - Institute for Water, Energy and Sustainability, Steyrergasse 17, 8010 Graz (Austria); Zwart, R. [Energy Research Centre of The Netherlands (ECN), Westerduinweg 3, 1755 LE Petten (Netherlands)

2012-03-15

In this paper, the greenhouse gas and energy balances of the production and use for space heating of substitute natural gas from biomass (bio-SNG) for space heat are analysed. These balances are compared to the use of natural gas and solid biomass as wood chips to provide the same service. The reduction of the greenhouse gas emissions (CO{sub 2}-eq.) - carbon dioxide, methane and nitrous oxide - and of the fossil primary energy use is investigated in a life cycle assessment (LCA). This assessment was performed for nine systems for bio-SNG; three types of gasification technologies (O{sub 2}-blown entrained flow, O{sub 2}-blown circulating fluidised bed and air-steam indirect gasification) with three different types of feedstock (forest residues, miscanthus and short rotation forestry). The greenhouse gas analysis shows that forest residues using the air-steam indirect gasification technology result in the lowest greenhouse gas emissions (in CO{sub 2}-eq. 32 kg MWh{sup -1} of heat output). This combination results in 80% reduction of greenhouse gas emissions when compared to natural gas and a 29% reduction of greenhouse gases if the forest residues were converted to wood chips and combusted. The gasification technologies O{sub 2}-blown entrained flow and O{sub 2}-blown circulating fluidised bed gasification have higher greenhouse gas emissions that range between in CO{sub 2}-eq. 41 to 75 kg MWh{sup -1} of heat output depending on the feedstock. When comparing feedstocks in the bio-SNG systems, miscanthus had the highest greenhouse gas emissions bio-SNG systems producing in CO2-eq. 57-75 kg MWh{sup -1} of heat output. Energy analysis shows that the total primary energy use is higher for bio-SNG systems (1.59-2.13 MWh MWh{sup -1} of heat output) than for the reference systems (in 1.37-1.51 MWh MWh{sup -1} of heat output). However, with bio-SNG the fossil primary energy consumption is reduced compared to natural gas. For example, fossil primary energy use is reduced by

Diffusion of improved biomass stoves in China

International Nuclear Information System (INIS)

Daxiong Qiu; Shuhua Gu; Catania, P.; Kun Huang

1996-01-01

The large-scale utilization of inefficient biofuel stoves for cooking and heating in the rural areas of China can cause ecological and environmental problems; thus, in 1982, the Chinese government encouraged the diffusion of improved biomass stoves. From 1982 to 1994, these improved biomass stoves have been used by 144 million households or the equivalent of 90% of all improved stoves installed globally; 62% of the Chinese market has been penetrated. This paper presents the fundamental features of China's diffusion programme of improved biomass stoves, analyses of the future domestic market, and defines some of the lessons learned from the diffusion programme which may be applicable in other emerging nations. (Author)

Laboratory-scale method for enzymatic saccharification of lignocellulosic biomass at high-solids loadings

Directory of Open Access Journals (Sweden)

Dibble Clare J

2009-11-01

Full Text Available Abstract Background Screening new lignocellulosic biomass pretreatments and advanced enzyme systems at process relevant conditions is a key factor in the development of economically viable lignocellulosic ethanol. Shake flasks, the reaction vessel commonly used for screening enzymatic saccharifications of cellulosic biomass, do not provide adequate mixing at high-solids concentrations when shaking is not supplemented with hand mixing. Results We identified roller bottle reactors (RBRs as laboratory-scale reaction vessels that can provide adequate mixing for enzymatic saccharifications at high-solids biomass loadings without any additional hand mixing. Using the RBRs, we developed a method for screening both pretreated biomass and enzyme systems at process-relevant conditions. RBRs were shown to be scalable between 125 mL and 2 L. Results from enzymatic saccharifications of five biomass pretreatments of different severities and two enzyme preparations suggest that this system will work well for a variety of biomass substrates and enzyme systems. A study of intermittent mixing regimes suggests that mass transfer limitations of enzymatic saccharifications at high-solids loadings are significant but can be mitigated with a relatively low amount of mixing input. Conclusion Effective initial mixing to promote good enzyme distribution and continued, but not necessarily continuous, mixing is necessary in order to facilitate high biomass conversion rates. The simplicity and robustness of the bench-scale RBR system, combined with its ability to accommodate numerous reaction vessels, will be useful in screening new biomass pretreatments and advanced enzyme systems at high-solids loadings.

Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller

OpenAIRE

Soons, Z.I.T.A.; IJssel, van den, J.; Pol, van der, L.A.; Straten, van, G.; Boxtel, van, A.J.B.

2009-01-01

Abstract This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation of the oxygen uptake rate, the starting point for online monitoring and control of biomass growth, taking into account the dynamics in the gas-phase. Mixing effects and delays are caused by amongst ...

Combined heat and power system with advanced gasification technology for biomass wastes

Energy Technology Data Exchange (ETDEWEB)

Mochida, S.; Abe, T.; Yasuda, T. [Nippon Furnace Kogyo Kaisha Ltd, Yokohama (Japan); Gupta, A.K. [Maryland Univ., College Park, MD (United States). Dept. of Mechnical Engineering

2013-07-01

The results obtained from an advanced gasification system utilizing high temperature steam are presented here. The results showed successful demonstration of clean syngas production having high calorific value fuel ({proportional_to}10 MJ/m{sup 3}N) using woody biomass wastes in a downdraft type gasifier. The gasification capacity of the plant on dry basis was 60 kg/h. The syngas produced can be utilized in an absorption type chiller for air conditioning. This advanced gasification technology allows one to transform wastes to clean energy at local production sites without any environmental impact and expensive waste transportation costs. The experience gained from the demonstration plant allows one to implement to other industrial applications for use as a decentralized unit and obtain clean syngas for local use. The demonstration conducted here shows that the system is favorable for onsite use of compatible combined heat and power (CHP) system including light oil supported diesel engine power generator. The biomass waste fuel from a lumber mill factory was used in this study. The factory handles a wide forests area of about 50 ha and produces about 2,500 m{sup 3}/year of wood chips from thin out trees and waste lumbers. This translates to a maximum 110 kg/h of wood chips that can be fed to a gasifier. The syngas produced was used for the combined heat and power system. Local use of biomass for fuel reforming reduces the cost of collection and transportation costs so that a sustainable business is demonstrated with profit from the generated electricity and thermal energy. The cost structure incorporates both the depreciation cost and operation cost of the system. Thermal energy from hot water can be used for drying lumbers and wood chips in a cascade manner. The drying process can be adopted for enhancing its productivity with increased variability on the quality of lumber. The results show that the combined heat and power system (CHP) offers good profitable

Solid biomass barometer

International Nuclear Information System (INIS)

Anon.

2011-01-01

The primary energy production from solid biomass in the European Union reached 79.3 Mtoe in 2010 which implies a growth rate of 8% between 2009 and 2010. The trend, which was driven deeper by Europe's particularly cold winter of 2009-2010, demonstrates that the economic down-turn failed to weaken the member states' efforts to structure the solid biomass sector. Heat consumption rose sharply: the volume of heat sold by heating networks increased by 18% and reached 6.7 Mtoe and if we consider the total heat consumption (it means with and without recovery via heating networks) the figure is 66 Mtoe in 2010, which amounts to 10.1% growth. The growth of electricity production continued through 2010 (8.3% up on 2009) and rose to 67 TWh but at a slower pace than in 2009 (when it rose by 11.3% on 2008). The situation of the main producer countries: Sweden, Finland, Germany and France is reviewed. It appears that cogeneration unit manufacturers and biomass power plant constructors are the main beneficiaries of the current biomass energy sector boom. There is a trend to replace coal-fired plants that are either obsolete or near their end of life with biomass or multi-fuel plants. These opportunities will enable the industry to develop and further exploit new technologies such as gasification, pyrolysis and torrefaction which will enable biomass to be turned into bio-coal. (A.C.)

DUE GlobBiomass - Estimates of Biomass on a Global Scale

Science.gov (United States)

Eberle, J.; Schmullius, C.

2017-12-01

For the last three years, a new ESA Data User Element (DUE) project had focussed on creating improved knowledge about the Essential Climate Variable Biomass. The main purpose of the DUE GlobBiomass project is to better characterize and to reduce uncertainties of AGB estimates by developing an innovative synergistic mapping approach in five regional sites (Sweden, Poland, Mexico, Kalimantan, South Africa) for the epochs 2005, 2010 and 2015 and for one global map for the year 2010. The project team includes leading Earth Observation experts of Europe and is linked through Partnership Agreements with further national bodies from Brazil, Canada, China, Russia and South Africa. GlobBiomass has demonstrated how EO observation data can be integrated with in situ measurements and ecological understanding to provide improved biomass estimates that can be effectively exploited by users. The target users had mainly be drawn from the climate and carbon cycle modelling communities and included users concerned with carbon emissions and uptake due to biomass changes within initiatives such as REDD+. GlobBiomass provided a harmonised structure that can be exploited to address user needs for biomass information, but will be capable of being progressively refined as new data and methods become available. This presentation will give an overview of the technical prerequisites and final results of the GlobBiomass project.

Performance evaluation of a biomass boiler on the basis of heat loss method and total heat values of steam

International Nuclear Information System (INIS)

Munir, A.; Alvi, J.Z.; Ashfaq, S.; Ghafoor, A.

2014-01-01

Pakistan being an agricultural country has large resources of biomass in the form of crop residues like wood, wheat straw, rice husk, cotton sticks and bagasse. Power generation using biomass offers an excellent opportunity to overcome current scenario of energy crises. Of the all biomass resources, bagasse is one of the potential energy sources which can be successfully utilized for power generation. During the last decade, bagasse fired boilers attained major importance due to increasing prices of primary energy (e.g. fossil fuels). Performance of a bagasse fired boiler was evaluated at Shakarganj Sugar Mill, Bhone-Jhang having steam generation capacity of 80 tons h/sup -1/at 25 bar working pressure. The unit was forced circulation and bi-drum type water tube boiler which was equipped with all accessories like air heater, economizer and super-heater. Flue gas analyzer and thermocouples were used to record percent composition and temperature of flue gases respectively. Physical analysis of bagasse showed gross calorific value of bagasse as 2326 kCal kg/sup -1/. Ultimate analysis of bagasse was performed and the actual air supplied to the boiler was calculated to be 4.05 kg per kg of bagasse under the available resources of the plant. Performance evaluation of the boiler was carried out and a complete heat balance sheet was prepared to investigate the different sources of heat losses. The efficiency of the boiler was evaluated on the basis of heat losses through boiler and was found to be 56.08%. It was also determined that 2 kg of steam produced from 1 kg of bagasse under existing condition of the boiler. The performance evaluation of the boiler was also done on the basis of total heat values of steam and found to be 55.98%. The results obtained from both the methods were found almost similar. Effects of excess air, stack and ambient temperature on the efficiency of boiler have also been evaluated and presented in the manuscript. (author)

Re-thinking china's densified biomass fuel policies: Large or small scale?

International Nuclear Information System (INIS)

Shan, Ming; Li, Dingkai; Jiang, Yi; Yang, Xudong

2016-01-01

Current policies and strategies related to the utilization of densified biomass fuel (DBF) in China are mainly focused on medium- or large-scale manufacturing modes, which cannot provide feasible solutions to solve the household energy problems in China's rural areas. To simplify commercial processes related to the collection of DBF feedstock and the production and utilization of fuel, a novel village-scale DBF approach is proposed. Pilot demonstration projects have shown the feasibility and flexibility of this new approach in realizing sustainable development in rural China. Effective utilization of DBF in rural China will lead to gains for global, regional, and local energy savings, environmental protection, sustainable development, and related social benefits. It could also benefit other developing countries for better utilization of biomass as a viable household energy source. This proposal therefore delivers the possibility of reciprocal gains, and as such deserves the attention of policy makers and various stakeholders. - Highlights: •A field survey of Chinese densified biomass fuel (DBF) development is conducted. •The current situation and problems related to China's DBF industry are analyzed. •A novel and viable village-scale DBF utilization mode is proposed. •Further actions are suggested to boost the utilization of DBF in rural China.

Effect of materials mixture on the higher heating value: Case of biomass, biochar and municipal solid waste.

Science.gov (United States)

Boumanchar, Imane; Chhiti, Younes; M'hamdi Alaoui, Fatima Ezzahrae; El Ouinani, Amal; Sahibed-Dine, Abdelaziz; Bentiss, Fouad; Jama, Charafeddine; Bensitel, Mohammed

2017-03-01

The heating value describes the energy content of any fuel. In this study, this parameter was evaluated for different abundant materials in Morocco (two types of biochar, plastic, synthetic rubber, and cardboard as municipal solid waste (MSW), and various types of biomass). Before the evaluation of their higher heating value (HHV) by a calorimeter device, the thermal behavior of these materials was investigated using thermogravimetric (TGA) and Differential scanning calorimetry (DSC) analyses. The focus of this work is to evaluate the calorific value of each material alone in a first time, then to compare the experimental and theoretical HHV of their mixtures in a second time. The heating value of lignocellulosic materials was between 12.16 and 20.53MJ/kg, 27.39 for biochar 1, 32.60MJ/kg for biochar 2, 37.81 and 38.00MJ/kg for plastic and synthetic rubber respectively and 13.81MJ/kg for cardboard. A significant difference was observed between the measured and estimated HHVs of mixtures. Experimentally, results for a large variety of mixture between biomass/biochar and biomass/MSW have shown that the interaction between biomass and other compounds expressed a synergy of 2.37% for biochar 1 and 6.11% for biochar 2, 1.09% for cardboard, 5.09% for plastic and 5.01% for synthetic rubber. Copyright © 2016 Elsevier Ltd. All rights reserved.

Oxy-fuel combustion of coal and biomass, the effect on radiative and convective heat transfer and burnout

Energy Technology Data Exchange (ETDEWEB)

Smart, John P.; Patel, Rajeshriben; Riley, Gerry S. [RWEnpower, Windmill Hill Business Park, Whitehill Way, Swindon, Wiltshire SN5 6PB, England (United Kingdom)

2010-12-15

This paper focuses on results of co-firing coal and biomass under oxy-fuel combustion conditions on the RWEn 0.5 MWt Combustion Test Facility (CTF). Results are presented of radiative and convective heat transfer and burnout measurements. Two coals were fired: a South African coal and a Russian Coal under air and oxy-fuel firing conditions. The two coals were also co-fired with Shea Meal at a co-firing mass fraction of 20%. Shea Meal was also co-fired at a mass fraction of 40% and sawdust at 20% with the Russian Coal. An IFRF Aerodynamically Air Staged Burner (AASB) was used. The thermal input was maintained at 0.5 MWt for all conditions studied. The test matrix comprised of varying the Recycle Ratio (RR) between 65% and 75% and furnace exit O{sub 2} was maintained at 3%. Carbon-in-ash samples for burnout determination were also taken. Results show that the highest peak radiative heat flux and highest flame luminosity corresponded to the lowest recycle ratio. The effect of co-firing of biomass resulted in lower radiative heat fluxes for corresponding recycle ratios. Furthermore, the highest levels of radiative heat flux corresponded to the lowest convective heat flux. Results are compared to air firing and the air equivalent radiative and convective heat fluxes are fuel type dependent. Reasons for these differences are discussed in the main text. Burnout improves with biomass co-firing under both air and oxy-fuel firing conditions and burnout is also seen to improve under oxy-fuel firing conditions compared to air. (author)

Wallowa County Integrated Biomass Energy Center

Energy Technology Data Exchange (ETDEWEB)

Christoffersen, Nils [Wallowa Resources Community Solutions Inc., Wallowa, OR (United States)

2014-05-02

The Integrated Biomass Energy Center (IBEC) is an approximately 0.1 MW CHP integrated biorefinery in Northeastern Oregon which will demonstrate and validate small-scale combined heat and power from lignin intermediates/residues. IBEC will be co-located with feedstock suppliers and thermal and power customers for distributed generation. The project was developed by Wallowa Resources Community Solutions Inc.

Combined heat treatment and acid hydrolysis of cassava grate waste (CGW) biomass for ethanol production

Energy Technology Data Exchange (ETDEWEB)

Agu, R.C.; Amadife, A.E.; Ude, C.M.; Onyia, A.; Ogu, E.O. [Enugu State Univ. of Science and Technology (Nigeria). Faculty of Applied Natural Sciences; Okafor, M.; Ezejiofor, E. [Nnamdi Azikiwe Univ., Awka (Nigeria). Dept. of Applied Microbiology

1997-12-31

The effect of combined heat treatment and acid hydrolysis (various concentrations) on cassava grate waste (CGW) biomass for ethanol production was investigated. At high concentrations of H{sub 2}SO{sub 4} (1--5 M), hydrolysis of the CGW biomass was achieved but with excessive charring or dehydration reaction. At lower acid concentrations, hydrolysis of CGW biomass was also achieved with 0.3--0.5 M H{sub 2}SO{sub 4}, while partial hydrolysis was obtained below 0.3 M H{sub 2}SO{sub 4} (the lowest acid concentration that hydrolyzed CGW biomass) at 120 C and 1 atm pressure for 30 min. A 60% process efficiency was achieved with 0.3 M H{sub 2}SO{sub 4} in hydrolyzing the cellulose and lignin materials present in the CGW biomass. High acid concentration is therefore not required for CGW biomass hydrolysis. The low acid concentration required for CGW biomass hydrolysis, as well as the minimal cost required for detoxification of CGW biomass because of low hydrogen cyanide content of CGW biomass would seem to make this process very economical. From three liters of the CGW biomass hydrolysate obtained from hydrolysis with 0.3M H{sub 2}SO{sub 4}, ethanol yield was 3.5 (v/v%) after yeast fermentation. However, although the process resulted in gainful utilization of CGW biomass, additional costs would be required to effectively dispose new by-products generated from CGW biomass processing.

The effect of assessment scale and metric selection on the greenhouse gas benefits of woody biomass

International Nuclear Information System (INIS)

Galik, Christopher S.; Abt, Robert C.

2012-01-01

Recent attention has focused on the net greenhouse gas (GHG) implications of using woody biomass to produce energy. In particular, a great deal of controversy has erupted over the appropriate manner and scale at which to evaluate these GHG effects. Here, we conduct a comparative assessment of six different assessment scales and four different metric calculation techniques against the backdrop of a common biomass demand scenario. We evaluate the net GHG balance of woody biomass co-firing in existing coal-fired facilities in the state of Virginia, finding that assessment scale and metric calculation technique do in fact strongly influence the net GHG balance yielded by this common scenario. Those assessment scales that do not include possible market effects attributable to increased biomass demand, including changes in forest area, forest management intensity, and traditional industry production, generally produce less-favorable GHG balances than those that do. Given the potential difficulty small operators may have generating or accessing information on the extent of these market effects, however, it is likely that stakeholders and policy makers will need to balance accuracy and comprehensiveness with reporting and administrative simplicity. -- Highlights: ► Greenhouse gas (GHG) effects of co-firing forest biomass with coal are assessed. ► GHG effect of replacing coal with forest biomass linked to scale, analytic approach. ► Not accounting for indirect market effects yields poorer relative GHG balances. ► Accounting systems must balance comprehensiveness with administrative simplicity.

Topology optimization for nano-scale heat transfer

DEFF Research Database (Denmark)

Evgrafov, Anton; Maute, Kurt; Yang, Ronggui

2009-01-01

We consider the problem of optimal design of nano-scale heat conducting systems using topology optimization techniques. At such small scales the empirical Fourier's law of heat conduction no longer captures the underlying physical phenomena because the mean-free path of the heat carriers, phonons...... in our case, becomes comparable with, or even larger than, the feature sizes of considered material distributions. A more accurate model at nano-scales is given by kinetic theory, which provides a compromise between the inaccurate Fourier's law and precise, but too computationally expensive, atomistic...

Evaluation of energy plantation crops in a high-throughput indirectly heated biomass gasifier

Energy Technology Data Exchange (ETDEWEB)

Paisley, M.A.; Litt, R.D. [Battelle, Columbus, OH (United States)

1993-12-31

Experiments were run in Battelle`s 10 ton per day Process Research Unit (PRU) gasifier using two high-growth, energy plantation crops -- hybrid poplar -- and an herbaceous biomass crop -- switch grass. The results show that both feedstocks provide gas production rates, product gas compositions, and heating value similar to other biomass feedstocks tested in the Battelle gasification process. The ash compositions of the switch grass and hybrid poplar feedstocks were high in potassium relative to previously tested biomass feedstocks. High growth biomass species tend to concentrate minerals such as potassium in the ash. The higher potassium content in the ash can then cause agglomeration problems in the gasification system. A method for controlling this agglomeration through the addition of small amounts (approximately 2 percent of the wood feed rate) of an additive could adequately control the agglomeration tendency of the ash. During the testing program in the PRU, approximately 50 tons of hybrid poplar and 15 tons of switch grass were gasified to produce a medium Btu product gas.

Simulated performance of biomass gasification based combined power and refrigeration plant for community scale application

Energy Technology Data Exchange (ETDEWEB)

Chattopadhyay, S., E-mail: suman.mech09@gmail.com [Department of Mechanical Engineering, NIT, Agarpara, Kolkata – 700109, West Bengal (India); Mondal, P., E-mail: mondal.pradip87@gmail.com; Ghosh, S., E-mail: sudipghosh.becollege@gmail.com [Department of Mechanical Engineering, IIEST, Shibpur, Howrah – 711103, West Bengal (India)

2016-07-12

Thermal performance analysis and sizing of a biomass gasification based combined power and refrigeration plant (CPR) is reported in this study. The plant is capable of producing 100 kWe of electrical output while simultaneously producing a refrigeration effect, varying from 28-68 ton of refrigeration (TR). The topping gas turbine cycle is an indirectly heated all-air cycle. A combustor heat exchanger duplex (CHX) unit burns producer gas and transfer heat to air. This arrangement avoids complex gas cleaning requirements for the biomass-derived producer gas. The exhaust air of the topping GT is utilized to run a bottoming ammonia absorption refrigeration (AAR) cycle via a heat recovery steam generator (HRSG), steam produced in the HRSG supplying heat to the generator of the refrigeration cycle. Effects of major operating parameters like topping cycle pressure ratio (r{sub p}) and turbine inlet temperature (TIT) on the energetic performance of the plant are studied. Energetic performance of the plant is evaluated via energy efficiency, required biomass consumption and fuel energy savings ratio (FESR). The FESR calculation method is significant for indicating the savings in fuel of a combined power and process heat plant instead of separate plants for power and process heat. The study reveals that, topping cycle attains maximum power efficiency of 30%in pressure ratio range of 8-10. Up to a certain value of pressure ratio the required air flow rate through the GT unit decreases with increase in pressure ratio and then increases with further increase in pressure ratio. The capacity of refrigeration of the AAR unit initially decreases up to a certain value of topping GT cycle pressure ratio and then increases with further increase in pressure ratio. The FESR is found to be maximized at a pressure ratio of 9 (when TIT=1100°C), the maximum value being 53%. The FESR is higher for higher TIT. The heat exchanger sizing is also influenced by the topping cycle pressure ratio

Cleaning of biomass derived product gas for engine applications and for co-firing in PC-boilers

Energy Technology Data Exchange (ETDEWEB)

Kurkela, E; Staahlberg, P; Laatikainen-Luntama, J [VTT Energy, Espoo (Finland). Energy Production Technologies; and others

1997-10-01

The conventional fluidized-bed combustion has become commercially available also to relatively small scale (5 MWe), but this technology has rather low power-to-heat ratio and consequently it`s potential is limited to applications where district or process heat is the main product. Thus, there seems to be a real need to develop more efficient methods for small-scale power production from biomass. Gasification diesel power plant is one alternative for the small-scale power production, which has clearly higher power-to-heat ratio than can be reached in conventional steam cycles. The main technical problem in this process is the gas cleaning from condensable tars. In addition to the diesel-power plants, there are several other interesting applications for atmospheric-pressure clean gas technology. One alternative for cost-effective biomass utilization is co-firing of biomass derived product gas in existing pulverized coal fired boilers (or other types of boilers and furnaces). The aim of the project is to develop dry gas cleaning methods for gasification-diesel power plants and for other atmospheric-pressure applications of biomass and waste gasification. The technical objectives of the project are as follows: To develop and test catalytic gas cleaning methods for engine. To study the removal of problematic ash species of (CFE) gasification with regard to co-combustion of the product gas in PC boilers. To evaluate the technical and economical feasibility of different small-scale power plant concepts based on fixed-bed updraft and circulating fluidized- bed gasification of biomass and waste. (orig.)

Co-firing of coal with biomass and waste in full-scale suspension-fired boilers

Energy Technology Data Exchange (ETDEWEB)

Dam-Johansen, Kim; Frandsen, Flemming J.; Jensen, Peter A.; Jensen, Anker D. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of chemical and Biochemical Engineering

2013-07-01

The energy policy in Denmark has for many years focused on lowering the net CO{sub 2} emission from heat and power production by replacing fossil fuels by renewable resources. This has been done by developing dedicated grate-fired boilers for biomass and waste fuels but also by developing coal-based suspension-fired boilers to accept still higher fractions of biomass or waste material as fuels. This last development has been challenging of many reasons, including pre-treatment of fuels, and solving potential emission and operational problems during the simultaneous development of supercritical steam cycles with steam temperatures close to 600 C, providing power efficiencies close to 50% (Hein KRG, Sustainable energy supply and environment protection - strategies, resources and technologies. In: Gupta R, Wall T, Hupa M, Wigley F, Tillman D, Frandsen FJ (eds) Proceedings of international conference on impact of fuel quality on power production and the environment, Banff Conference Centre, Banff, Alberta, Canada, 29 Sept-4 Oct, 2008). For 25 years the CHEC (Combustion and Harmful Emission Control) Research Centre at DTU Chemical Engineering, has attained a leading role in research, supporting power producing industry, plant owners and boiler manufacturers to optimize design and operation and minimize cost and environmental impact using alternative fuels in suspension fired boilers. Our contribution has been made via a combination of full-scale measuring campaigns, pilot-scale studies, lab-scale measurements and modeling tools. The research conducted has addressed many issues important for co-firing, i.e. fuel processing, ash induced boiler deposit formation and corrosion, boiler chamber fuel conversion and emission formation, influence on flue gas cleaning equipment and the utilization of residual products. This chapter provides an overview of research activities, aiming at increasing biomass shares during co-firing in suspension, conducted in close collaboration with

Cogeneration: One way to use biomass efficiently

International Nuclear Information System (INIS)

Gustavsson, L.; Johansson, B.

1993-01-01

Cogeneration in district heating systems is the most energy-efficient way to convert biomass into heat and electricity with current or nearly commercial technologies. Methanol produced from biomass and used in vehicles instead of petrol or diesel could reduce carbon dioxide emissions nearly as much per unit of biomass as if the biomass were used to replace natural gas for cogeneration, but at some higher cost per unit of carbon dioxide reduction. The most energy-efficient way to use biomass for cogeneration appears to be combined cycle technology, and the world's first demonstration plant is now being built. Potentially, this technology can be used for electricity production in Swedish district heating systems to provide nearly 20% of current Swedish electricity production, while simultaneously reducing carbon dioxide emissions from the district heating systems by some 55%. The heat costs from cogeneration with biomass are higher than the heat costs from fossil fuel plants at current fuel prices. Biomass can only compete with fossil fuel if other advantages, for example a lower environmental impact are considered. (au) (35 refs.)

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

Directory of Open Access Journals (Sweden)

Jai-Houng Leu

2010-01-01

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

Biomass gasification--a substitute to fossil fuel for heat application

International Nuclear Information System (INIS)

Dasappa, S.; Sridhar, H.V.; Sridhar, G.; Paul, P.J.; Mukunda, H.S.

2003-01-01

The paper addresses case studies of a low temperature and a high temperature industrial heat requirement being met using biomass gasification. The gasification system for these applications consists of an open top down draft reburn reactor lined with ceramic. Necessary cooling and cleaning systems are incorporated in the package to meet the end use requirements. The other elements included are the fuel conveyor, water treatment plant for recirculating the cooling water and adequate automation to start, shut down and control the operations of the gasifier system. Drying of marigold flower, a low temperature application is considered to replace diesel fuel in the range of 125-150 l h -1 . Gas from the 500 kg h -1 , gasifier system is piped into the producer gas burners fixed in the combustion chamber with the downstream process similar to the diesel burner. The high temperature application is for a heat treatment furnace in the temperature range of 873-1200 K. A 300 kg h -1 of biomass gasifier replaces 2000 l of diesel or LDO per day completely. The novelty of this package is the use of one gasifier to energize 16 burners in the 8 furnaces with different temperature requirements. The system operates over 140 h per week on a nearly nonstop mode and over 4000 h of operation replacing fossil fuel completely. The advantage of bioenergy package towards the economic and environmental considerations is presented

Integrated Biorefinery for Conversion of Biomass to Ethanol, Synthesis Gas, and Heat

Energy Technology Data Exchange (ETDEWEB)

Leon, Gerson [Abengoa Bioenergy, Hugoton, KS (United States)

2017-06-20

Goal of the project was to Design, build and operate a commercial scale bioethanol facility that uses sustainable biomass feedstock, drastically reduces greenhouse gas (GHG) emissions while achieving output production, yield and cost targets.

Air emissions of small-scale (< 10 MW) biomass boilers. Review of three field tests; Developpement d'un calorimetre a eau pour la dosimetrie au LNE-LNHB

Energy Technology Data Exchange (ETDEWEB)

Autret, E. [Agence de l' Environnement et de la Maitrise de l' Energie, ADEME, 49 - Angers (France)

2011-01-15

Objectives of greenhouse gases emission reduction, which encourages bio-energy development for heat purposes, are compatible with air-quality policies if the concept of clean biomass combustion is applied. This paper presents actual emission levels of atmospheric pollutants of small-scale (< 10 MW) biomass boilers from a review of three field tests carried out between 2007 and 2009. 31 biomass boilers have been audited to cover the large diversity of sites under operation in terms of fuels, power, flue-gas cleaning devices.. Results are compared to actual and forecasted regulations. The review shows that fuel quality and operation are key issues to ensure low emissions of organic pollutants (OC, VOC, CnHm, PCDD/F, PAH, PCB, HCB), SO{sub 2}, NO{sub x}, fine particulate matters, metallic compounds. Installation design (power, flue-gas cleaning techno logy) also has a major impact on organic pollutants and fine particulate matter emissions. A large majority of boilers have very low emission levels. Guidelines are finally stated to keep on promoting small-scale biomass boilers in order to be air-quality compatible and efficient to fight climate change. (author)

Feasibility study : identifying economic opportunities for bugwood and other biomass resources in Alberta and BC

International Nuclear Information System (INIS)

2008-04-01

This feasibility study discussed energy technologies for biomass feedstocks including mill residues, roadside residues, and non-merchantable tree stands in Alberta and British Columbia (BC). The study demonstrated that the lack of mill residue resources means that targeted government support may be needed to help the energy industry to use more costly resources such as roadside residue or bugwood. Government policies are also needed to support the long-term availability of biomass supplies in order to lower the supply risks related to the use of biomass resources in the energy industry. Lower prices for power in both provinces make the use of biomass unfavourable for small-scale technologies under 10 MW. However, cogeneration projects using biomass showed higher returns when power conversion efficiency was low. Higher revenues were generated from heat sales displacing natural gas than from electricity sales at current tariffs. Large-scale biomass power plants were viable when lower-cost feedstocks were available. Bio-oils were suitable as supplements for heat generation in cogeneration processes. Pellet production was also viable using less expensive feedstocks.The co-firing of biomass at coal plants required little capital investment. The study demonstrated that Alberta's power production incentive of $60 per MWh was sufficient to improve the economics of small-scale projects. It was recommended that the program be continued and paid out over a period of 10 years. It was concluded that specific electricity tariffs and incentives are needed to accelerate regrowth and create a viable biomass industry for the future. 33 refs., 45 tabs., 17 figs

Biomass ignition in mills and storages – is it explained by conventional thermal ignition theory?

DEFF Research Database (Denmark)

Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

of the process, which can then be incorporated into refined models of self-ignition for biomass and other organic solids. In the present study, the slow, transient heating of several lignocellulosic biomasses and a bituminous coal from ambient temperature to around 300° C were investigated in a lab scale tube...

Laboratory Scale Coal And Biomass To Drop-In Fuels (CBDF) Production And Assessment

Energy Technology Data Exchange (ETDEWEB)

Lux, Kenneth [Altex Technologies Corporation, Sunnyvale, CA (United States); Imam, Tahmina [Altex Technologies Corporation, Sunnyvale, CA (United States); Chevanan, Nehru [Altex Technologies Corporation, Sunnyvale, CA (United States); Namazian, Mehdi [Altex Technologies Corporation, Sunnyvale, CA (United States); Wang, Xiaoxing [Pennsylvania State Univ., University Park, PA (United States); Song, Chunshan [Pennsylvania State Univ., University Park, PA (United States)

2016-06-29

This Final Technical Report describes the work and accomplishments of the project entitled, “Laboratory Scale Coal and Biomass to Drop-In Fuels (CBDF) Production and Assessment.” The main objective of the project was to fabricate and test a lab-scale liquid-fuel production system using coal containing different percentages of biomass such as corn stover and switchgrass at a rate of 2 liters per day. The system utilizes the patented Altex fuel-production technology, which incorporates advanced catalysts developed by Pennsylvania State University. The system was designed, fabricated, tested, and assessed for economic and environmental feasibility relative to competing technologies.

Small-Scale Coal-Biomass to Liquids Production Using Highly Selective Fischer-Tropsch Synthesis

Energy Technology Data Exchange (ETDEWEB)

Gangwal, Santosh K. [Southern Research Institute, Durham, NC (United States); McCabe, Kevin [Southern Research Institute, Durham, NC (United States)

2015-04-30

The research project advanced coal-to-liquids (CTL) and coal-biomass to liquids (CBTL) processes by testing and validating Chevron’s highly selective and active cobalt-zeolite hybrid Fischer-Tropsch (FT) catalyst to convert gasifier syngas predominantly to gasoline, jet fuel and diesel range hydrocarbon liquids, thereby eliminating expensive wax upgrading operations The National Carbon Capture Center (NCCC) operated by Southern Company (SC) at Wilsonville, Alabama served as the host site for the gasifier slip-stream testing/demonstration. Southern Research designed, installed and commissioned a bench scale skid mounted FT reactor system (SR-CBTL test rig) that was fully integrated with a slip stream from SC/NCCC’s transport integrated gasifier (TRIG^TM). The test-rig was designed to receive up to 5 lb/h raw syngas augmented with bottled syngas to adjust the H₂/CO molar ratio to 2, clean it to cobalt FT catalyst specifications, and produce liquid FT products at the design capacity of 2 to 4 L/day. It employed a 2-inch diameter boiling water jacketed fixed-bed heat-exchange FT reactor incorporating Chevron’s catalyst in Intramicron’s high thermal conductivity micro-fibrous entrapped catalyst (MFEC) packing to efficiently remove heat produced by the highly exothermic FT reaction.

A microeconomic analysis of decentralized small scale biomass based CHP plants—The case of Germany

International Nuclear Information System (INIS)

Wittmann, Nadine; Yildiz, Özgür

2013-01-01

Alternative energy sources, such as biomass CHP plants, have recently gained significantly in importance and action is due both on the large scale corporate level and on the small scale. Hence, making the scope and economic outline of such projects easily intelligible without losing relevant details seems a key factor to further promote the necessary developments. The model setup presented in this paper may therefore serve as a starting point for generating numerical results based on real life cases or scenarios. Its focus lies on the economic analysis of decentralized biomass CHP plants. It presents a new approach to analyzing the economic aspects of biomass CHP plants implementing a formal microeconomic approach. As Germany claims a leading role in the market for renewable energy production, the paper also takes a closer look on the effects of German energy policy with respect to biomass CHP plants. - Highlights: • A formal microeconomic model is used to analyse a decentralized biomass CHP plant. • Model setup is used to generate numerical results based on real life scenarios. • Nested CES production function is a new approach to model economics of biomass CHP. • Analysis presents insight into microeconomics and cost drivers of biomass CHP. • Evaluation of energy policy design with respect to environmental policy goals

Biosorption of the metal-complex dye Acid Black 172 by live and heat-treated biomass of Pseudomonas sp. strain DY1: Kinetics and sorption mechanisms

Energy Technology Data Exchange (ETDEWEB)

Du, Lin-Na; Wang, Bing [College of Life Science, Zhejiang University, 310058, Hangzhou, Zhejiang Province (China); Li, Gang [Department of Agriculture and Biotechnology, Wenzhou Vocational College of Science and Technology, 325006 Wenzhou, Zhejiang Province (China); Wang, Sheng [College of Life Science, Zhejiang University, 310058, Hangzhou, Zhejiang Province (China); Crowley, David E., E-mail: crowley@ucr.edu [Department of Environmental Science, University of California, Riverside, CA 92521 (United States); Zhao, Yu-Hua, E-mail: yhzhao225@zju.edu.cn [College of Life Science, Zhejiang University, 310058, Hangzhou, Zhejiang Province (China)

2012-02-29

Highlights: Black-Right-Pointing-Pointer The maximum amount of Acid Black 172 sorption was about 2.98 mmol/g biomass. Black-Right-Pointing-Pointer Amine groups played a major role in the biosorption of Acid Black 172. Black-Right-Pointing-Pointer The reasons of increased dye sorption by heat-treated biomass were proposed. - Abstract: The ability of Pseudomonas sp. strain DY1 to adsorb Acid Black 172 was studied to determine the kinetics and mechanisms involved in biosorption of the dye. Kinetic data for adsorption fit a pseudo-second-order model. Increased initial dye concentration could significantly enhance the amount of dye adsorbed by heat-treated biomass in which the maximum amount of dye adsorbed was as high as 2.98 mmol/g biomass, whereas it had no significant influence on dye sorption by live biomass. As treated temperature increased, the biomass showed gradual increase of dye sorption ability. Experiments using potentiometric titration and Fourier transform infrared spectroscopy (FTIR) indicated that amine groups (NH{sub 2}) played a prominent role in biosorption of Acid Black 172. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM) analysis indicated that heat treatment of the biomass increased the permeability of the cell walls and denatured the intracellular proteins. The results of biosorption experiments by different cell components confirmed that intracellular proteins contributed to the increased biosorption of Acid Black 172 by heat-treated biomass. The data suggest that biomass produced by this strain may have application for removal of metal-complex dyes from wastewater streams generated from the dye products industry.

Characterization and Quantification of Deposits Buildup and Removal in Biomass Suspension-Fired Boilers

DEFF Research Database (Denmark)

Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming

2010-01-01

Utilization of biomass as wood or straw in large suspension­fired boilers is an efficient method to reduce the use of fossil fuels consumption and to reduce the net CO2 formation. However, the presence of chlorine and alkali metals in biomass (straw) generate ash with a low melting point and induce...... large problems of ash deposit formation on the superheater tubes. Full scale studies on biomass ash deposition and removal had been done on biomass grate boilers, while only limited data is available from biomass suspension­firing. The aim of this study was to investigate deposit mass uptake, heat...... uptake reduction, fly ash and deposit characteristics, and deposit removal by using an advanced online deposit probe in a suspension­fired boiler using wood and straw pellets as fuel. The influence of fuel type and probe exposure time on the ash deposition rate, the heat uptake, the fly ash and deposit...

Modeling heat efficiency, flow and scale-up in the corotating disc scraped surface heat exchanger

DEFF Research Database (Denmark)

Friis, Alan; Szabo, Peter; Karlson, Torben

2002-01-01

A comparison of two different scale corotating disc scraped surface heat exchangers (CDHE) was performed experimentally. The findings were compared to predictions from a finite element model. We find that the model predicts well the flow pattern of the two CDHE's investigated. The heat transfer...... performance predicted by the model agrees well with experimental observations for the laboratory scale CDHE whereas the overall heat transfer in the scaled-up version was not in equally good agreement. The lack of the model to predict the heat transfer performance in scale-up leads us to identify the key...

Combined Heat and Power Systems for the Provision of Sustainable Energy from Biomass in Buildings

OpenAIRE

Ortwein Andreas

2016-01-01

Against the background of greenhouse gases causing climate change, combined heat and power (CHP) systems fueled by biomass can efficiently supply energy with high flexibility. Such CHP systems will usually consist of one or more thermo-chemical conversion steps and at least one (the more or less separated) electric power generation unit. Depending on the main products of the previous conversion steps (e.g. combustible gases or liquids, but also flue gases with sensible heat), different techno...

A Calorimetric Assay For Enzymatic Saccharification Of Biomass

DEFF Research Database (Denmark)

Murphy, Leigh; Borch, Kim; McFarland, K.C.

2010-01-01

A limited selection of assay and screening methodologies for cellulolytic enzymes has been stated as a restriction in biomass research. In this report we test the potential of isothermal calorimetry for this purpose. The primary observable in this technique (the heat flow in Watts), scales with t...... of the regulation and functional mechanism of cellulases....

Time scale dependent negative emission potential of forests and biomass plantations via wood burial, torrefied biomass, biochar and pyrogas condensate sequestration in soil

Science.gov (United States)

Schmidt, Hans-Peter; Kammann, Claudia; Lucht, Wolfgang; Gerten, Dieter; Foidl, Nikolaus

2017-04-01

The efficiency of Negative Emission Technologies (NET) is dependent on (1) the transformation of the biomass carbon into a form that can be sequestered, (2) the mean residence time of the sequestered carbon, (3) the regrowth and thus carbon re-accumulation of the harvested biomass, and (4) the positive or negative priming of soil carbon. These four parameters define the time scale dependent C-balance of various NET-Systems and permit a global economic and environmental evaluation. As far as geologic CO2 storage is considered to be feasible with close to zero losses and if the energy for transport, transformation and disposal is taken from the process bioenergy, conventional BE-CCS has a C sequestration potential of 50 - 70 % depending on the type of biomass and the technology used. Beside unknown risks of deep stored CO2 and high costs, regrowth of C-accumulating biomass is hampered in the long-term as not only carbon but also essential soil nutrients are mined. Under this scenario, biomass regrowth is expected to slow down and soil carbon content to decrease. These factors enlarge the time horizon until a BE-CCS system becomes carbon neutral and eventual carbon negative (when biomass regrowth exceeds the difference between the harvested biomass carbon and BE-CCS stored carbon). Thermal treatment of biomass under a low oxygen regime (torrefaction, pyrolysis, gasification) can transform up to 85% of biomass carbon into various solid and liquid forms of recalcitrant carbon that can be sequestered. Depending on the process parameters and temperature, the mean residence time of the torrefied or pyrolysed biomass can last from several decennials to centennials when applied to the soil of the biomass production site. The carbon can thus be stored at comparatively low costs within the ecosystem itself. As the thermal treatment preserves most of the biomass-accumulated nutrients (except N), natural nutrient cycles are maintained within the biomass system. Depending on the

Remarks on energetic biomass

International Nuclear Information System (INIS)

Mathis, Paul; Pelletier, Georges

2011-01-01

The authors report a study of energy biomass by considering its three main sources (forest, agriculture and wastes) and three energy needs (heat, fuel for transports, electricity) in the French national context. After having recalled the various uses of biomass (animal feeding, energy production, materials, chemical products), the authors discuss the characteristics of biomass with respect to other energy sources. Then, they analyse and discuss the various energy needs which biomass could satisfy: heat production (in industry, in the residential and office building sector), fuel for transports, electricity production. They assess and discuss the possible biomass production of its three main sources: forest, agriculture, and wastes (household, agricultural and industrial wastes). They also discuss the opportunities for biogas production and for second generation bio-fuel production

Development of Solar Biomass Drying System

Directory of Open Access Journals (Sweden)

Atnaw Samson Mekbib

2017-01-01

Full Text Available The purpose of this paper focuses on the experimental pre-treatment of biomass in agricultural site using solar energy as power source and contribution of common use and efficiency solar dryer system for consumer. The main purpose of this design for solar cabinet dryer is to dry biomass via direct and indirect heating. Direct heating is the simplest method to dry biomass by exposing the biomass under direct sunlight. The solar cabinet dryer traps solar heat to increase the temperature of the drying chamber. The biomass absorbs the heat and transforms the moisture content within the biomass into water vapour and then leaves the chamber via the exhaust air outlet. This problem however can be solved by adopting indirect solar drying system. High and controllable temperatures can be achieved as a fan is used to move the air through the solar collector. This project has successfully created a solar cabinet dryer that combines both direct and indirect solar drying systems and functions to dry biomass as well as crops effectively and efficiently with minimal maintenance. Hence, it is indeed a substitution for conventional dryers which are affordable to local farmers.

Empirical scaling for present ohmic heated tokamaks

International Nuclear Information System (INIS)

Daughney, C.

1975-06-01

Empirical scaling laws are given for the average electron temperature and electron energy confinement time as functions of plasma current, average electron density, effective ion charge, toroidal magnetic field, and major and minor plasma radius. The ohmic heating is classical, and the electron energy transport is anomalous. The present scaling indicates that ohmic-heating becomes ineffective with larger experiments. (U.S.)

Biomass thermochemical gasification: Experimental studies and modeling

Science.gov (United States)

Kumar, Ajay

The overall goals of this research were to study the biomass thermochemical gasification using experimental and modeling techniques, and to evaluate the cost of industrial gas production and combined heat and power generation. This dissertation includes an extensive review of progresses in biomass thermochemical gasification. Product gases from biomass gasification can be converted to biopower, biofuels and chemicals. However, for its viable commercial applications, the study summarizes the technical challenges in the gasification and downstream processing of product gas. Corn stover and dried distillers grains with solubles (DDGS), a non-fermentable byproduct of ethanol production, were used as the biomass feedstocks. One of the objectives was to determine selected physical and chemical properties of corn stover related to thermochemical conversion. The parameters of the reaction kinetics for weight loss were obtained. The next objective was to investigate the effects of temperature, steam to biomass ratio and equivalence ratio on gas composition and efficiencies. DDGS gasification was performed on a lab-scale fluidized-bed gasifier with steam and air as fluidizing and oxidizing agents. Increasing the temperature resulted in increases in hydrogen and methane contents and efficiencies. A model was developed to simulate the performance of a lab-scale gasifier using Aspen Plus(TM) software. Mass balance, energy balance and minimization of Gibbs free energy were applied for the gasification to determine the product gas composition. The final objective was to optimize the process by maximizing the net energy efficiency, and to estimate the cost of industrial gas, and combined heat and power (CHP) at a biomass feedrate of 2000 kg/h. The selling price of gas was estimated to be 11.49/GJ for corn stover, and 13.08/GJ for DDGS. For CHP generation, the electrical and net efficiencies were 37 and 86%, respectively for corn stover, and 34 and 78%, respectively for DDGS. For

Surplus biomass through energy efficient kilns

International Nuclear Information System (INIS)

Anderson, Jan-Olof; Westerlund, Lars

2011-01-01

Highlights: → The magnitude of the national heat demand for drying lumber in kilns is established. → Each part of the total heat consumption is divided and shown between the main drying conditions. → The potential to increase the energy efficiency in kilns with available techniques is presented. → The market demand for the biomass, available with increase kiln energy efficiency, is reviled. -- Abstract: The use of biomass in the European Union has increased since the middle of the 1990s, mostly because of high subsidies and CO 2 emission regulation through the Kyoto protocol. The sawmills are huge biomass suppliers to the market; out of the Swedish annual lumber production of 16.4 Mm 3 , 95% is produced by medium to large-volume sawmills with a lumber quotient of 47%. The remaining part is produced as biomass. An essential part (12%) of the entering timber is used for supply of heat in their production processes, mostly in the substantial drying process. The drying process is the most time and heat consuming process in the sawmill. This study was undertaken to determine the sawmills' national use of energy and potential magnitude of improvements. If the drying process can be made more effective, sawmills' own use of biomass can be decreased and allow a considerably larger supply to the biomass market through processed or unprocessed biomass, heat or electricity production. The national electricity and heat usage when drying the lumber have been analysed by theoretical evaluation and experimental validation at a batch kiln. The main conclusion is that the heat consumption for drying lumber among the Swedish sawmills is 4.9 TW h/year, and with available state-of-the-art techniques it is possible to decrease the national heat consumption by approximately 2.9 TW h. This additional amount of energy corresponds to the market's desire for larger energy supply.

Particulate emission reduction in small-scale biomass combustion plants by a condensing heat exchanger

NARCIS (Netherlands)

Best, de C.J.J.M.; Kemenade, van H.P.; Brunner, T.; Obernberger, I.

2008-01-01

Use of biomass fuels for energy purposes has gained increasing importance as a method to reduce greenhouse gas emissions. In comparison to gaseous and liquid fossil fuels, the emissions of particulate matter are higher, leading to concerns about the availability of cost-effective techniques to

Operating Experiences with a Small-scale CHP Pilot Plant based on a 35 kWel Hermetic Four Cylinder Stirling Engine for Biomass Fuels

DEFF Research Database (Denmark)

Biedermann, F.; Carlsen, Henrik; Schoech, M.

2003-01-01

Within the scope of the RD&D project presented a small-scale CHP plant with a hermetic four cylinder Stirling engine for biomass fuels was developed and optimised in cooperation with the Technical University of Denmark, MAWERA Holzfeuerungsanlagen GesmbH, an Austrian biomass furnace and boiler...... exchanger of the Stirling engine, of the air preheater and of the entire combustion system. Furthermore, the optimisation of the pneumatic cleaning system to reduce ash deposition in the hot heat exchanger is of great relevance....... manufacturer, and BIOS BIOENERGIESYSTEME GmbH, an Austrian development and engineering company. Based on the technology developed, a pilot plant was designed and erected in Austria. The nominal electric power output of the plant is 35 kWel and the nominal thermal output amounts to approx. 220 kWth. The plant...

Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller

NARCIS (Netherlands)

Soons, Z.I.T.A.; IJssel, van den J.; Pol, van der L.A.; Straten, van G.; Boxtel, van A.J.B.

2009-01-01

Abstract This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation

An update technology for integrated biomass gasification combined cycle power plant

International Nuclear Information System (INIS)

Bhattacharya, P.; Dey, S.

2014-01-01

A discussion is presented on the technical analysis of a 6.4 M W_e integrated biomass gasification combined cycle (IBGCC) plant. It features three numbers of downdraft biomass gasifier systems with suitable gas clean-up trains, three numbers of internal combustion (IC) producer gas engines for producing 5.85 MW electrical power in open cycle and 550 kW power in a bottoming cycle using waste heat. Comparing with IC gas engine single cycle systems, this technology route increases overall system efficiency of the power plant, which in turn improves plant economics. Estimated generation cost of electricity indicates that mega-watt scale IBGCC power plants can contribute to good economies of scale in India. This paper also highlight's the possibility of activated carbon generation from the char, a byproduct of gasification process, and use of engine's jacket water heat to generate chilled water through VAM for gas conditioning. (author)

Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller.

Science.gov (United States)

Soons, Zita I T A; van den IJssel, Jan; van der Pol, Leo A; van Straten, Gerrit; van Boxtel, Anton J B

2009-04-01

This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation of the oxygen uptake rate, the starting point for online monitoring and control of biomass growth, taking into account the dynamics in the gas-phase. Mixing effects and delays are caused by amongst others the headspace and tubing to the analyzer. These gas phase dynamics are modelled using knowledge of the system in order to reconstruct oxygen consumption. The second aspect is to evaluate performance of the monitoring and control system with the required modifications of the oxygen consumption calculation on pilot-scale. In pilot-scale fed-batch cultivation good monitoring and control performance is obtained enabling a doubled concentration of bulk vaccine compared to standard batch production.

Impact of different national biomass policies on investment costs of biomass district heating plants. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-04-01

The BIO-COST project - co-ordinated by E.V.A. - was funded by the European Commission's THERMIE Type B Programme. The objective of BIO-COST was to analyse the impact of national biomass policies on the investment costs of biomass district heating (DH) plants. The European comparison should help identifying measures to reduce investment costs for biomass DH plants and/or components down to a 'best practice' level. The investigation is based on the comparison of 20 biomass DH plants by country, with Denmark and Sweden having mainly high energy taxes as driver, while Austria and France rely mainly on subsidy systems. The results of BIO-COST show, that governmental policies can have a big impact especially on grid and buildings costs, effecting of course the overall costs of the plant enormously. Emission standards have their effects especially on the costs for technical equipment, however, this fact was not reflected in the BIO-COST data. The results do not show a clear advantage of either the energy tax approach or the subsidy approach: The French subsidy approach leads to fairly low cost levels compared to the Danish tax approach, while the Swedish tax approach seems to yield the lowest cost level. On the other hand the Austrian subsidy approach seems to intercrease investment costs. In principle both the tax as the subsidy approach can lead to the same effect: a project is calculated in such a way, that it just meets economic breakeven. This is typically the case when the project is not carried out by a private enterprise but by an operator aiming at enhanced public welfare (e.g. co-operative, municipality). In this case a subsidy model might yield more possibilities to encourage an economically efficient development, than a tax. Instead of giving subsidies as a fixed percentage of investments they could be adjusted to the actual needs of the project as proven by a standardised calculation. Of course this can create the incentive to expect higher

Energetic and economical comparison for biomass fuel

International Nuclear Information System (INIS)

Galins, A.; Grundulis, A.; Zihmane, K.

2003-01-01

The common agricultural biomass, such as wheat straw, rape straw, wheat small corn, wheat forage, rape oil cakes and other, we can use as fuel for heat production. The biomass application for burning depends on economical situation on agriculture and fuel market. Energetic and economical parameters of agricultural biomass are estimated and compared to wooden grain. As parameters for comparison used the biomass heat value Q (MJ/kg), specific cost per 1 kWh heat production C 0 (Ls/kWh) and the fuel consumption per 1 kWh heat production M 0 (kg/kWh). The rape oil cakes have best heat value (20.82 MJ/kg), but cheapest heat energy we can get from rape straw (0.0046 Ls/kWh). Expenses of heat production for forge wheat corn (0.011 Ls/kWh) are alike to wooden chip (0.0103 Ls/kWh) and wooden grain (0.0122 Ls/kWh) (authors)

An investigation into a laboratory scale bubble column humidification dehumidification desalination system powered by biomass energy

International Nuclear Information System (INIS)

Rajaseenivasan, T.; Srithar, K.

2017-01-01

Highlights: • A biomass based humidification dehumidification desalination system is tested. • System is analyzed with the direct and preheated air supply. • Highest distillate rate of 6.1 kg/h is collected with the preheated air supply. • The minimum fuel feed of 0.2 kg is needed to produce 1 kg of fresh water. - Abstract: This article describes a biomass powered bubble column humidification-dehumidification desalination system. This system mainly consists of a biomass stove, air heat exchanger, bubble column humidifier and dehumidifier. Saw dust briquettes are used as biomass fuel in the stove. First level of experiments are carried out in bubble column humidifier with ambient air supply to select the best water depth, bubble pipe hole diameter and water temperature. Experiments are conducted by integrating the humidifier with the dehumidifier. Air is sent to the humidifier with and without pre-heating. Preheating of air is carried out in the air heat exchanger by using the flue gas and flame from the combustion chamber. It is observed that the humidifier ability is augmented with the rise in water depth, water temperature, mass flow rate of air and cooling water flow rate, and reduction in bubble pipe hole diameter. It is found from Taguchi analysis that the water temperature dominates in controlling the humidifier performance compared to other parameters. Better specific humidity is recorded with a bubble pipe hole diameter of 1 mm, water depth of 170 mm and water temperature of 60 °C. Highest distillate of 6.1 kg/h and 3.5 kg/h is collected for the HDH desalination system with preheated air and direct air supply respectively. Recovery of waste heat using an air heat exchanger reduces the fuel consumption from 0.36 kg to 0.2 kg for producing 1 kg of distilled water. Lowest distilled water cost of 0.0133 US $/kg through preheated air supply and 0.0231 US $/kg through direct air supply is observed. A correlation is developed to estimate the mass transfer

Micro-Scale Regenerative Heat Exchanger

Science.gov (United States)

Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

2004-01-01

A micro-scale regenerative heat exchanger has been designed, optimized and fabricated for use in a micro-Stirling device. Novel design and fabrication techniques enabled the minimization of axial heat conduction losses and pressure drop, while maximizing thermal regenerative performance. The fabricated prototype is comprised of ten separate assembled layers of alternating metal-dielectric composite. Each layer is offset to minimize conduction losses and maximize heat transfer by boundary layer disruption. A grating pattern of 100 micron square non-contiguous flow passages were formed with a nominal 20 micron wall thickness, and an overall assembled ten-layer thickness of 900 microns. Application of the micro heat exchanger is envisioned in the areas of micro-refrigerators/coolers, micropower devices, and micro-fluidic devices.

The Forest Energy Chain in Tuscany: Economic Feasibility and Environmental Effects of Two Types of Biomass District Heating Plant

Directory of Open Access Journals (Sweden)

Claudio Fagarazzi

2014-09-01

Full Text Available The purpose of this study was to examine two biomass district heating plants operating in Tuscany, with a specific focus on the ex-post evaluation of their economic and financial feasibility and of their environmental benefits. The former biomass district heating plant supplies only public users (Comunità Montana della Lunigiana, CML: administrative body that coordinates the municipalities located in mountain areas, the latter supplies both public and private users (Municipality of San Romano in Garfagnana. Ex-post investment analysis was performed to check both the consistency of results with the forecasts made in the stage of the project design and on the factors, which may have reduced or jeopardized the estimated economic performance of the investment (ex-ante assessment. The results of the study point out appreciable results only in the case of biomass district heating plants involving private users and fuelled by biomasses sourced from third parties. In this case, the factors that most influence ex-post results include the conditions of the woody biomass local market (market prices, the policies of energy selling prices to private users and the temporal dynamics of private users’ connection. To ensure the consistency of ex-post economic outcome with the expected results it is thus important to: (i have good knowledge of the woody local market; (ii define energy selling prices that should be cheap for private users but consistent with energy production costs and (iii constrain private users beforehand to prevent errors in the plant design and in the preliminary estimate of return on investment. Moreover, the results obtained during the monitoring activities could help in providing information on the effectiveness of the supporting measures adopted and also to orient future choices of policy makers and particularly designers, to identify the most efficient configuration of district heating organization for improving energy and

Devolatilization kinetics of woody biomass at short residence times and high heating rates and peak temperatures

DEFF Research Database (Denmark)

Johansen, Joakim M.; Gadsbøll, Rasmus; Thomsen, Jesper

2016-01-01

This work combines experimental and computational fluid dynamics (CFD) results to derive global kinetics for biomass (pine wood) devolatilization during heating rates on the order of 105Ks-1, bulk flow peak temperatures between 1405 and 1667K, and particle residence times below 0.1s. Experiments......Jmol-1. The accuracy of the derived global kinetics was supported by comparing predictions to experimental results from a 15kW furnace. The work emphasizes the importance of characterizing the temperature history of the biomass particles when deriving pyrolysis kinetics. The present results indicate...

Design of Biomass Combined Heat and Power (CHP Systems based on Economic Risk using Minimax Regret Criterion

Directory of Open Access Journals (Sweden)

Ling Wen Choong

2018-01-01

Full Text Available It is a great challenge to identify optimum technologies for CHP systems that utilise biomass and convert it into heat and power. In this respect, industry decision makers are lacking in confidence to invest in biomass CHP due to economic risk from varying energy demand. This research work presents a linear programming systematic framework to design biomass CHP system based on potential loss of profit due to varying energy demand. Minimax Regret Criterion (MRC approach was used to assess maximum regret between selections of the given biomass CHP design based on energy demand. Based on this, the model determined an optimal biomass CHP design with minimum regret in economic opportunity. As Feed-in Tariff (FiT rates affects the revenue of the CHP plant, sensitivity analysis was then performed on FiT rates on the selection of biomass CHP design. Besides, design analysis on the trend of the optimum design selected by model was conducted. To demonstrate the proposed framework in this research, a case study was solved using the proposed approach. The case study focused on designing a biomass CHP system for a palm oil mill (POM due to large energy potential of oil palm biomass in Malaysia.

A computationally inexpensive CFD approach for small-scale biomass burners equipped with enhanced air staging

International Nuclear Information System (INIS)

Buchmayr, M.; Gruber, J.; Hargassner, M.; Hochenauer, C.

2016-01-01

Highlights: • Time efficient CFD model to predict biomass boiler performance. • Boundary conditions for numerical modeling are provided by measurements. • Tars in the product from primary combustion was considered. • Simulation results were validated by experiments on a real-scale reactor. • Very good accordance between experimental and simulation results. - Abstract: Computational Fluid Dynamics (CFD) is an upcoming technique for optimization and as a part of the design process of biomass combustion systems. An accurate simulation of biomass combustion can only be provided with high computational effort so far. This work presents an accurate, time efficient CFD approach for small-scale biomass combustion systems equipped with enhanced air staging. The model can handle the high amount of biomass tars in the primary combustion product at very low primary air ratios. Gas-phase combustion in the freeboard was performed by the Steady Flamelet Model (SFM) together with a detailed heptane combustion mechanism. The advantage of the SFM is that complex combustion chemistry can be taken into account at low computational effort because only two additional transport equations have to be solved to describe the chemistry in the reacting flow. Boundary conditions for primary combustion product composition were obtained from the fuel bed by experiments. The fuel bed data were used as fuel inlet boundary condition for the gas-phase combustion model. The numerical and experimental investigations were performed for different operating conditions and varying wood-chip moisture on a special designed real-scale reactor. The numerical predictions were validated with experimental results and a very good agreement was found. With the presented approach accurate results can be provided within 24 h using a standard Central Processing Unit (CPU) consisting of six cores. Case studies e.g. for combustion geometry improvement can be realized effectively due to the short calculation

Combined Heat and Power Systems for the Provision of Sustainable Energy from Biomass in Buildings

Directory of Open Access Journals (Sweden)

Ortwein Andreas

2016-01-01

Full Text Available Against the background of greenhouse gases causing climate change, combined heat and power (CHP systems fueled by biomass can efficiently supply energy with high flexibility. Such CHP systems will usually consist of one or more thermo-chemical conversion steps and at least one (the more or less separated electric power generation unit. Depending on the main products of the previous conversion steps (e.g. combustible gases or liquids, but also flue gases with sensible heat, different technologies are available for the final power conversion step. This includes steam cycles with steam turbines or engines and different working fluids (water, organic fluids, but also combustion based systems like gas turbines or gas engines. Further promising technologies include fuel cells with high electric efficiency. When integrating such CHP systems in buildings, there are different strategies, especially concerning electric power generation. While some concepts are focusing on base load production, others are regulated either by thermal or by electric power demand. The paper will give a systematic overview on the combination of thermo-chemical conversion of biomass and combined heat and power production technologies. The mentioned building integration strategies will be discussed, leading to conclusions for further research and development in that field.

Modeling and experiments of biomass combustion in a large-scale grate boiler

DEFF Research Database (Denmark)

Yin, Chungen; Rosendahl, Lasse; Kær, Søren Knudsen

2007-01-01

is inherently more difficult due to the complexity of the solid biomass fuel bed on the grate, the turbulent reacting flow in the combustion chamber and the intensive interaction between them. This paper presents the CFD validation efforts for a modern large-scale biomass-fired grate boiler. Modeling...... and experiments are both done for the grate boiler. The comparison between them shows an overall acceptable agreement in tendency. However at some measuring ports, big discrepancies between the modeling and the experiments are observed, mainly because the modeling-based boundary conditions (BCs) could differ...

Large Scale Solar Heating

DEFF Research Database (Denmark)

Heller, Alfred

2001-01-01

The main objective of the research was to evaluate large-scale solar heating connected to district heating (CSDHP), to build up a simulation tool and to demonstrate the application of the simulation tool for design studies and on a local energy planning case. The evaluation was mainly carried out...... model is designed and validated on the Marstal case. Applying the Danish Reference Year, a design tool is presented. The simulation tool is used for proposals for application of alternative designs, including high-performance solar collector types (trough solar collectors, vaccum pipe collectors......). Simulation programs are proposed as control supporting tool for daily operation and performance prediction of central solar heating plants. Finaly the CSHP technolgy is put into persepctive with respect to alternatives and a short discussion on the barries and breakthrough of the technology are given....

Combined hydraulic and biomass power - an answer to economic and ecological adaptation pressure on the energy supply system

International Nuclear Information System (INIS)

Pistauer, M.

1991-01-01

On the large scale, there will be an economic pressure in the European Communities on coal and oil from the CO 2 taxes. The economic and ecological advantages of a combination of hydraulic and biomass power in Austria are emphasized. In particular a biomass remote heating pilot project is announced. (Quittner)

Dry season biomass estimation as an indicator of rangeland quantity using multi-scale remote sensing data

CSIR Research Space (South Africa)

Ramoelo, Abel

2014-10-01

Full Text Available vegetation is green and photosynthetic active. During dry season, biomass estimation is always not plausible using vegetation indices. The aim of this study is to estimate dry biomass using the multi-scale remote sensing data in the savanna ecosystem. Field...

Biomass Energy for Transport and Electricity: Large scale utilization under low CO2 concentration scenarios

Energy Technology Data Exchange (ETDEWEB)

Luckow, Patrick; Wise, Marshall A.; Dooley, James J.; Kim, Son H.

2010-01-25

This paper examines the potential role of large scale, dedicated commercial biomass energy systems under global climate policies designed to stabilize atmospheric concentrations of CO2 at 400ppm and 450ppm. We use an integrated assessment model of energy and agriculture systems to show that, given a climate policy in which terrestrial carbon is appropriately valued equally with carbon emitted from the energy system, biomass energy has the potential to be a major component of achieving these low concentration targets. The costs of processing and transporting biomass energy at much larger scales than current experience are also incorporated into the modeling. From the scenario results, 120-160 EJ/year of biomass energy is produced by midcentury and 200-250 EJ/year by the end of this century. In the first half of the century, much of this biomass is from agricultural and forest residues, but after 2050 dedicated cellulosic biomass crops become the dominant source. A key finding of this paper is the role that carbon dioxide capture and storage (CCS) technologies coupled with commercial biomass energy can play in meeting stringent emissions targets. Despite the higher technology costs of CCS, the resulting negative emissions used in combination with biomass are a very important tool in controlling the cost of meeting a target, offsetting the venting of CO2 from sectors of the energy system that may be more expensive to mitigate, such as oil use in transportation. The paper also discusses the role of cellulosic ethanol and Fischer-Tropsch biomass derived transportation fuels and shows that both technologies are important contributors to liquid fuels production, with unique costs and emissions characteristics. Through application of the GCAM integrated assessment model, it becomes clear that, given CCS availability, bioenergy will be used both in electricity and transportation.

Characterization of biomass combustion at high temperatures based on an upgraded single particle model

International Nuclear Information System (INIS)

Li, Jun; Paul, Manosh C.; Younger, Paul L.; Watson, Ian; Hossain, Mamdud; Welch, Stephen

2015-01-01

Highlights: • High temperature rapid biomass combustion is studied based on single particle model. • Particle size changes in devolatilization and char oxidation models are addressed. • Time scales of various thermal sub-processes are compared and discussed. • Potential solutions are suggested to achieve better biomass co-firing performances. - Abstract: Biomass co-firing is becoming a promising solution to reduce CO 2 emissions, due to its renewability and carbon neutrality. Biomass normally has high moisture and volatile contents, complicating its combustion behavior, which is significantly different from that of coal. A computational fluid dynamics (CFD) combustion model of a single biomass particle is employed to study high-temperature rapid biomass combustion. The two-competing-rate model and kinetics/diffusion model are used to model biomass devolatilization reaction and char burnout process, respectively, in which the apparent kinetics used for those two models were from high temperatures and high heating rates tests. The particle size changes during the devolatilization and char burnout are also considered. The mass loss properties and temperature profile during the biomass devolatilization and combustion processes are predicted; and the timescales of particle heating up, drying, devolatilization, and char burnout are compared and discussed. Finally, the results shed light on the effects of particle size on the combustion behavior of biomass particle

Large-scale production of Fischer-Tropsch diesel from biomass. Optimal gasification and gas cleaning systems

International Nuclear Information System (INIS)

Boerrigter, H.; Van der Drift, A.

2004-12-01

The paper is presented in the form of copies of overhead sheets. The contents concern definitions, an overview of Integrated biomass gasification and Fischer Tropsch (FT) systems (state-of-the-art, gas cleaning and biosyngas production, experimental demonstration and conclusions), some aspects of large-scale systems (motivation, biomass import) and an outlook

Burnout of pulverized biomass particles in large scale boiler - Single particle model approach

Energy Technology Data Exchange (ETDEWEB)

Saastamoinen, Jaakko; Aho, Martti; Moilanen, Antero [VTT Technical Research Centre of Finland, Box 1603, 40101 Jyvaeskylae (Finland); Soerensen, Lasse Holst [ReaTech/ReAddit, Frederiksborgsveij 399, Niels Bohr, DK-4000 Roskilde (Denmark); Clausen, Soennik [Risoe National Laboratory, DK-4000 Roskilde (Denmark); Berg, Mogens [ENERGI E2 A/S, A.C. Meyers Vaenge 9, DK-2450 Copenhagen SV (Denmark)

2010-05-15

Burning of coal and biomass particles are studied and compared by measurements in an entrained flow reactor and by modelling. The results are applied to study the burning of pulverized biomass in a large scale utility boiler originally planned for coal. A simplified single particle approach, where the particle combustion model is coupled with one-dimensional equation of motion of the particle, is applied for the calculation of the burnout in the boiler. The particle size of biomass can be much larger than that of coal to reach complete burnout due to lower density and greater reactivity. The burner location and the trajectories of the particles might be optimised to maximise the residence time and burnout. (author)

Increased combustion stability in modulating biomass boilers for district heating systems

Energy Technology Data Exchange (ETDEWEB)

Eriksson, Gunnar; Hermansson, Roger (eds.) [Lulea Univ. of Technology (Sweden)

2002-09-01

One of the problems in small district heating systems is the large load variation that must be handled by the system. If the boiler is designed to cover the needs during the coldest day in winter time in northern Europe it would have to run at loads as low as 10% of full load during summer time, when heat is needed only for tap water production. Load variations in small networks are quite fast and earlier investigations have shown that existing biomass boilers give rise to large amounts of harmful emissions at fast load variations and at low loads. The problem has been addressed in different ways: Three new boiler concepts have been realized and tested: A prototype of a 500 kW boiler with partitioned primary combustion chamber and supplied with a water heat store. A 10 kW bench scale combustor and a 500 kW prototype boiler based on pulsating combustion. Bench scale boilers to test the influence from applied sound on emissions and a 150 kW prototype boiler with a two-stage secondary vortex combustion chamber. Development of control and regulating equipment: Glow Guard, a control system using infra-red sensors to detect glowing char on the grate, has been constructed and tested. A fast prediction model that can be used in control systems has been developed. Simulation of the combustion process: Code to simulate pyrolysis/gasification of fuel on the grate has been developed. Combustion of the gas phase inside the combustion chamber has been simulated. The two models have been combined to describe the combustion process inside the primary chamber of a prototype boiler. A fast simulation code based on statistical methods that can predict the environmental performance of boilers has been developed. One of the boiler concepts matches the desired load span from 10 to 100% of full load with emissions far below the set limits for CO and THC and close to the set limits for NO{sub x}. The other boilers had a bit more narrow load range, one with very low emissions except for NO

Energy from biomass. Teaching material; Energie aus Biomasse. Ein Lehrmaterial

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-04-01

The textbook discusses the available options for power and heat generation from biomass as well as the limits of biomass-based power supply. The main obstacle apart from the high cost is a lack of knowledge, which the book intends to remedy. It addresses students of agriculture, forestry, environmental engineering, heating systems engineering and apprentice chimney sweepers, but it will also be useful to all other interested readers. [German] Biomasse kann aufgrund seiner vielfaeltigen Erscheinungs- und Umwandlungsformen sowohl als Brennstoff zur Waerme- und Stromgewinnung oder als Treibstoff eingesetzt werden. Die energetische Nutzung von Biomasse birgt zudem nicht zu verachtende Vorteile. Zum einen wegen des Beitrags zum Klimaschutz aufgrund der CO{sub 2}-Neutralitaet oder einfach, weil Biomasse immer wieder nachwaechst und von fossilen Ressourcen unabhaengig macht. All den bisher erschlossenen Moeglichkeiten der energetischen Nutzung von Biomasse moechte dieses Lehrbuch Rechnung tragen. Es zeigt aber auch die Grenzen auf, die mit der Energieversorgung durch Bioenergie einhergehen. Hohe Kosten und ein erhebliches Informationsdefizit behinderten bisher eine verstaerkte Nutzung dieses Energietraeges. Letzterem soll dieses Lehrbuch entgegenwirken. Das vorliegende Lehrbuch wurde fuer die Aus- und Weiterbildung erstellt. Es richtet sich vor allem an angehende Land- und Forstwirte, Umwelttechniker, Heizungsbauer und Schornsteinfeger, ist aber auch fuer all diejenigen interessant, die das Thema ''Energie aus Biomasse'' verstehen und ueberblicken moechten. (orig.)

Combustion and co-combustion of biomass in a bubbling fluidized bed boiler

NARCIS (Netherlands)

Khan, A.A.

2007-01-01

This PhD dissertation concerns the study of different aspects of biomass (co)-combustion in small-scale fluidized bed boilers for heat generation. The most renowned gaseous emissions from fluidized bed combustion, namely, CO and NO, are investigated with the help of experimental and theoretical

The Regional Biomass-Energy Agency (ERBE): an opportunity for the biomass-energy development in Wallonia

International Nuclear Information System (INIS)

Lemaire, P.; Menu, J.F.; Belle, J.F. van; Schenkel, Y.

1997-01-01

In 1995, the European Commission (Directorate-General for Energy) and the Walloon government set up a biomass-energy agency (ERBE), to promote and build biomass-energy projects in Wallonia (Belgium). A survey of biomass-energy potential indicates that wood-energy seems to offer the best utilization opportunities. Forest and logging residues, sawmills' and joineries' off-cuts, pallets residues, etc. could be burnt in wood district heating units with a significant social benefit. Consequently, the ERBE Agency is trying to set up projects in this way in Austria (+/- 100 wood heating systems) or in Sweden. It serves to inform industries and municipalities about biomass-energy, to advise them in the building of biomass-energy projects, to identify their energy needs and their biomass resources, to carry out prefeasibility studies, to inform them about financing opportunities, and so on. (author)

Biomass torrefaction: A promising pretreatment technology for biomass utilization

Science.gov (United States)

Chen, ZhiWen; Wang, Mingfeng; Ren, Yongzhi; Jiang, Enchen; Jiang, Yang; Li, Weizhen

2018-02-01

Torrefaction is an emerging technology also called mild pyrolysis, which has been explored for the pretreatment of biomass to make the biomass more favorable for further utilization. Dry torrefaction (DT) is a pretreatment of biomass in the absence of oxygen under atmospheric pressure and in a temperature range of 200-300 degrees C, while wet torrrefaction (WT) is a method in hydrothermal or hot and high pressure water at the tempertures within 180-260 degrees C. Torrrefied biomass is hydrophobic, with lower moisture contents, increased energy density and higher heating value, which are more comparable to the characteristics of coal. With the improvement in the properties, torrefied biomass mainly has three potential applications: combustion or co-firing, pelletization and gasification. Generally, the torrefaction technology can accelerate the development of biomass utilization technology and finally realize the maximum applications of biomass energy.

Romania biomass energy. Country study

Energy Technology Data Exchange (ETDEWEB)

Burnham, M; Easterly, J L; Mark, P E; Keller, A [DynCorp, Alexandria, VA (United States)

1995-12-01

The present report was prepared under contract to UNIDO to conduct a case study of biomass energy use and potential in Romania. The purpose of the case study is to provide a specific example of biomass energy issues and potential in the context of the economic transition under way in eastern Europe. The transition of Romania to a market economy is proceeding at a somewhat slower pace than in other countries of eastern Europe. Unfortunately, the former regime forced the use of biomass energy with inadequate technology and infrastructure, particularly in rural areas. The resulting poor performance thus severely damaged the reputation of biomass energy in Romania as a viable, reliable resource. Today, efforts to rejuvenate biomass energy and tap into its multiple benefits are proving challenging. Several sound biomass energy development strategies were identified through the case study, on the basis of estimates of availability and current use of biomass resources; suggestions for enhancing potential biomass energy resources; an overview of appropriate conversion technologies and markets for biomass in Romania; and estimates of the economic and environmental impacts of the utilization of biomass energy. Finally, optimal strategies for near-, medium- and long-term biomass energy development, as well as observations and recommendations concerning policy, legislative and institutional issues affecting the development of biomass energy in Romania are presented. The most promising near-term biomass energy options include the use of biomass in district heating systems; cofiring of biomass in existing coal-fired power plants or combined heat and power plants; and using co-generation systems in thriving industries to optimize the efficient use of biomass resources. Mid-term and long-term opportunities include improving the efficiency of wood stoves used for cooking and heating in rural areas; repairing the reputation of biogasification to take advantage of livestock wastes

Romania biomass energy. Country study

International Nuclear Information System (INIS)

Burnham, M.; Easterly, J.L.; Mark, P.E.; Keller, A.

1995-01-01

The present report was prepared under contract to UNIDO to conduct a case study of biomass energy use and potential in Romania. The purpose of the case study is to provide a specific example of biomass energy issues and potential in the context of the economic transition under way in eastern Europe. The transition of Romania to a market economy is proceeding at a somewhat slower pace than in other countries of eastern Europe. Unfortunately, the former regime forced the use of biomass energy with inadequate technology and infrastructure, particularly in rural areas. The resulting poor performance thus severely damaged the reputation of biomass energy in Romania as a viable, reliable resource. Today, efforts to rejuvenate biomass energy and tap into its multiple benefits are proving challenging. Several sound biomass energy development strategies were identified through the case study, on the basis of estimates of availability and current use of biomass resources; suggestions for enhancing potential biomass energy resources; an overview of appropriate conversion technologies and markets for biomass in Romania; and estimates of the economic and environmental impacts of the utilization of biomass energy. Finally, optimal strategies for near-, medium- and long-term biomass energy development, as well as observations and recommendations concerning policy, legislative and institutional issues affecting the development of biomass energy in Romania are presented. The most promising near-term biomass energy options include the use of biomass in district heating systems; cofiring of biomass in existing coal-fired power plants or combined heat and power plants; and using co-generation systems in thriving industries to optimize the efficient use of biomass resources. Mid-term and long-term opportunities include improving the efficiency of wood stoves used for cooking and heating in rural areas; repairing the reputation of biogasification to take advantage of livestock wastes

Computer aided heat transfer analysis in a laboratory scaled heat exchanger unit

International Nuclear Information System (INIS)

Gunes, M.

1998-01-01

In this study. an explanation of a laboratory scaled heat exchanger unit and a software which is developed to analyze heat transfer. especially to use it in heat transfer courses, are represented. Analyses carried out in the software through sample values measured in the heat exchanger are: (l) Determination of heat transfer rate, logarithmic mean temperature difference and overall heat transfer coefficient; (2)Determination of convection heat transfer coefficient inside and outside the tube and the effect of fluid velocity on these; (3)Investigation of the relationship between Nusselt Number. Reynolds Number and Prandtl Number by using multiple non-linear regression analysis. Results are displayed on the screen graphically

Optimization under uncertainty of a biomass-integrated renewable energy microgrid with energy storage

DEFF Research Database (Denmark)

Zheng, Yingying; Jenkins, Bryan M.; Kornbluth, Kurt

2018-01-01

Deterministic constrained optimization and stochastic optimization approaches were used to evaluate uncertainties in biomass-integrated microgrids supplying both electricity and heat. An economic linear programming model with a sliding time window was developed to assess design and scheduling...... of biomass combined heat and power (BCHP) based microgrid systems. Other available technologies considered within the microgrid were small-scale wind turbines, photovoltaic modules (PV), producer gas storage, battery storage, thermal energy storage and heat-only boilers. As an illustrative example, a case...... study was examined for a conceptual utility grid-connected microgrid application in Davis, California. The results show that for the assumptions used, a BCHP/PV with battery storage combination is the most cost effective design based on the assumed energy load profile, local climate data, utility tariff...

Scaling of Calcium Carbonate at Heated Surfaces in a Continuous System

OpenAIRE

Nergaard, Margrethe

2011-01-01

Scaling is the precipitation of a mineral layer on a surface. Sparingly soluble salts with inverse solubility, which calcium carbonate exhibits, will prefer precipitation at heated surfaces, making heat exchangers a target for scale formation. A continuous setup was used to study scale formation, the nature of the scale formed and scaling rate. An internally heated U-shaped tube was inserted into a continuously stirred tank, giving the same conditions for all scaling points. The experimental ...

Analysing biomass torrefaction supply chain costs.

Science.gov (United States)

Svanberg, Martin; Olofsson, Ingemar; Flodén, Jonas; Nordin, Anders

2013-08-01

The objective of the present work was to develop a techno-economic system model to evaluate how logistics and production parameters affect the torrefaction supply chain costs under Swedish conditions. The model consists of four sub-models: (1) supply system, (2) a complete energy and mass balance of drying, torrefaction and densification, (3) investment and operating costs of a green field, stand-alone torrefaction pellet plant, and (4) distribution system to the gate of an end user. The results show that the torrefaction supply chain reaps significant economies of scale up to a plant size of about 150-200 kiloton dry substance per year (ktonDS/year), for which the total supply chain costs accounts to 31.8 euro per megawatt hour based on lower heating value (€/MWhLHV). Important parameters affecting total cost are amount of available biomass, biomass premium, logistics equipment, biomass moisture content, drying technology, torrefaction mass yield and torrefaction plant capital expenditures (CAPEX). Copyright © 2013 Elsevier Ltd. All rights reserved.

A central solar-industrial waste heat heating system with large scale borehole thermal storage

NARCIS (Netherlands)

Guo, F.; Yang, X.; Xu, L.; Torrens, I.; Hensen, J.L.M.

2017-01-01

In this paper, a new research of seasonal thermal storage is introduced. This study aims to maximize the utilization of renewable energy source and industrial waste heat (IWH) for urban district heating systems in both heating and non-heating seasons through the use of large-scale seasonal thermal

Characterization of second generation biomass under thermal conversion and the fate of nitrogen

NARCIS (Netherlands)

Giuntoli, J.

2010-01-01

This dissertation deals with the characterization of several biomass materials under thermal conversion conditions using small--scale equipment. The fuels are tested under the conditions of slow and fast heating rate pyrolysis and combustion, with the main goal of investigating the chemistry of

Benefits of Allothermal Biomass Gasification for Co-Firing

Energy Technology Data Exchange (ETDEWEB)

Van der Meijden, C.M.; Van der Drift, A.; Vreugdenhil, B.J. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

2012-04-15

prevent ash entering the boiler. The calorific value of this carbon containing ash is lost. In allothermal gasifiers all the carbon containing ashes are combusted in the combustion section of the gasifier and the produced heat is used for the gasification process. The MILENA gasification technology is demonstrated at lab-scale (25 kWth) and pilot scale (800 kWth). A demonstration plant (11.6 MWth biomass input) will be constructed in Alkmaar (the Netherlands). Demolition wood will be used as fuel.

Biomass energy resource enhancement: the move to modern secondary energy forms

Energy Technology Data Exchange (ETDEWEB)

Craig, K; Overend, R P [National Renewable Energy Laboratory, Golden, CO (United States)

1995-12-01

to be disposed of in some other manner owing to its negative environmental impacts. The development cycle for biomass thus moves in a stepwise fashion. The first step is the gathering of wood and agricultural residues by families for cooking, heating and lighting. Next, investments are made in anaerobic digesters, which simultaneously address energy, environmental and hygiene needs, and in efficient wood- and straw-fired stoves, which improve the indoor air environment and reduce the depletion of forests for fuelwood. The final stage is the village-scale operation of digesters and gasifiers that provide distributed gas to households and enterprises not necessarily associated with agricultural or forestry activities. At this stage, industries that process biomass into pulp, paper, lumber and sugar (from sugar cane) can move from being merely self-sufficient in process heat needs to becoming significant exporters of electrical energy into the regional and national grids. The key to all these advances is the availability of highly efficient, environmentally sound and economically viable conversion technologies. (author) 21 refs, 6 figs, 1 tab

Biomass energy resource enhancement: the move to modern secondary energy forms

International Nuclear Information System (INIS)

Craig, K.; Overend, R.P.

1995-01-01

to be disposed of in some other manner owing to its negative environmental impacts. The development cycle for biomass thus moves in a stepwise fashion. The first step is the gathering of wood and agricultural residues by families for cooking, heating and lighting. Next, investments are made in anaerobic digesters, which simultaneously address energy, environmental and hygiene needs, and in efficient wood- and straw-fired stoves, which improve the indoor air environment and reduce the depletion of forests for fuelwood. The final stage is the village-scale operation of digesters and gasifiers that provide distributed gas to households and enterprises not necessarily associated with agricultural or forestry activities. At this stage, industries that process biomass into pulp, paper, lumber and sugar (from sugar cane) can move from being merely self-sufficient in process heat needs to becoming significant exporters of electrical energy into the regional and national grids. The key to all these advances is the availability of highly efficient, environmentally sound and economically viable conversion technologies. (author)

The Potential for Biomass District Energy Production in Port Graham, Alaska

Energy Technology Data Exchange (ETDEWEB)

Charles Sink, Chugachmiut; Keeryanne Leroux, EERC

2008-05-08

This project was a collaboration between The Energy & Environmental Research Center (EERC) and Chugachmiut – A Tribal organization Serving the Chugach Native People of Alaska and funded by the U.S. Department of Energy (DOE) Tribal Energy Program. It was conducted to determine the economic and technical feasibility for implementing a biomass energy system to service the Chugachmiut community of Port Graham, Alaska. The Port Graham tribe has been investigating opportunities to reduce energy costs and reliance on energy imports and support subsistence. The dramatic rise in the prices of petroleum fuels have been a hardship to the village of Port Graham, located on the Kenai Peninsula of Alaska. The Port Graham Village Council views the forest timber surrounding the village and the established salmon industry as potential resources for providing biomass energy power to the facilities in their community. Benefits of implementing a biomass fuel include reduced energy costs, energy independence, economic development, and environmental improvement. Fish oil–diesel blended fuel and indoor wood boilers are the most economical and technically viable options for biomass energy in the village of Port Graham. Sufficient regional biomass resources allow up to 50% in annual heating savings to the user, displacing up to 70% current diesel imports, with a simple payback of less than 3 years for an estimated capital investment under $300,000. Distributive energy options are also economically viable and would displace all imported diesel, albeit offering less savings potential and requiring greater capital. These include a large-scale wood combustion system to provide heat to the entire village, a wood gasification system for cogeneration of heat and power, and moderate outdoor wood furnaces providing heat to 3–4 homes or community buildings per furnace. Coordination of biomass procurement and delivery, ensuring resource reliability and technology acceptance, and arbitrating

Modeling and performance analysis of CCHP (combined cooling, heating and power) system based on co-firing of natural gas and biomass gasification gas

International Nuclear Information System (INIS)

Wang, Jiangjiang; Mao, Tianzhi; Sui, Jun; Jin, Hongguang

2015-01-01

Co-firing biomass and fossil energy is a cost-effective and reliable way to use renewable energy and offer advantages in flexibility, conversion efficiency and commercial possibility. This study proposes a co-fired CCHP (combined cooling, heating and power) system based on natural gas and biomass gasification gas that contains a down-draft gasifier, ICE (internal combustion engine), absorption chiller and heat exchangers. Thermodynamic models are constructed based on a modifying gasification thermochemical equilibrium model and co-fired ICE model for electricity and heat recovery. The performance analysis for the volumetric mixture ratio of natural gas and product gas indicates that the energy and exergy efficiencies are improved by 9.5% and 13.7%, respectively, for an increasing mixture ratio of 0–1.0. Furthermore, the costs of multi-products, including electricity, chilled water and hot water, based on exergoeconomic analysis are analyzed and discussed based on the influences of the mixture ratio of the two gas fuels, investment cost and biomass cost. - Highlights: • Propose a co-fired CCHP system by natural gas and biomass gasification gas. • Modify biomass gasification and co-fired ICE models. • Present the thermodynamic analysis of the volumetric mixture ratios of two gas fuels. • Energy and exergy efficiencies are improved 9.5% and 13.7%. • Discuss multi-products’ costs influenced by investment and fuel costs.

Pore-scale investigation of biomass plug development and propagation in porous media.

Science.gov (United States)

Stewart, Terri L; Scott Fogler, H

2002-03-05

Biomass plugging of porous media finds application in enhanced oil recovery and bioremediation. An understanding of biomass plugging of porous media was sought by using a porous glass micromodel through which biomass and nutrient were passed. This study describes the pore-scale physics of biomass plug propagation of Leuconostoc mesenteroides under nutrient-rich conditions. It was found that, as the nutrient flowed through the micromodel, the initial biomass plug occurred at the nutrient-inoculum interface due to growth in the larger pore throats. As growth proceeded, biomass filled and closed these larger pore throats, until only isolated groupings of pore throats with smaller radii remained empty. As nutrient flow continued, a maximum pressure drop was reached. At the maximum pressure drop, the biomass yielded in a manner similar to a Bingham plastic to form a breakthrough channel consisting of a path of interconnected pore throats. The channel incorporated the isolated groupings of empty pore throats that had been present before breakthrough. As the nutrient flow continued, subsequent plugs developed as breakthrough channels refilled with biomass and in situ growth was stimulated in the region just downstream of the previous plug. The downstream plugs had a higher fraction of isolated groupings of empty pore throats, which can be attributed to depletion of nutrient downstream. When the next breakthrough channel formed, it incorporated these isolated groupings, causing the breakthrough channels to be branched. It was observed that the newly formed plug could be less stable with this higher fraction of empty pore throats and that the location of breakthrough channels changed in subsequent plugs. This change in breakthrough channel location could be attributed to the redistribution of nutrient flow and the changes in flowrate in the pore throats. Copyright 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 577-588, 2002; DOI 10.1002/bit.10044

A Spatial Framework to Map Heat Health Risks at Multiple Scales.

Science.gov (United States)

Ho, Hung Chak; Knudby, Anders; Huang, Wei

2015-12-18

In the last few decades extreme heat events have led to substantial excess mortality, most dramatically in Central Europe in 2003, in Russia in 2010, and even in typically cool locations such as Vancouver, Canada, in 2009. Heat-related morbidity and mortality is expected to increase over the coming centuries as the result of climate-driven global increases in the severity and frequency of extreme heat events. Spatial information on heat exposure and population vulnerability may be combined to map the areas of highest risk and focus mitigation efforts there. However, a mismatch in spatial resolution between heat exposure and vulnerability data can cause spatial scale issues such as the Modifiable Areal Unit Problem (MAUP). We used a raster-based model to integrate heat exposure and vulnerability data in a multi-criteria decision analysis, and compared it to the traditional vector-based model. We then used the Getis-Ord G(i) index to generate spatially smoothed heat risk hotspot maps from fine to coarse spatial scales. The raster-based model allowed production of maps at spatial resolution, more description of local-scale heat risk variability, and identification of heat-risk areas not identified with the vector-based approach. Spatial smoothing with the Getis-Ord G(i) index produced heat risk hotspots from local to regional spatial scale. The approach is a framework for reducing spatial scale issues in future heat risk mapping, and for identifying heat risk hotspots at spatial scales ranging from the block-level to the municipality level.

Full-scale and time-scale heating experiments at Stripa: preliminary results. Technical project report No. 11

International Nuclear Information System (INIS)

Cook, N.G.W.; Hood, M.

1978-12-01

Two full-scale heating experiments and a time-scale heating experiment have recently been started in granite 340 meters below surface. The purpose of the full-scale heating experiments is to assess the near-field effects of thermal loading for the design of an underground repository of nuclear wastes. That of the time-scale heating experiments is to obtain field data of the interaction between heaters and its effect on the rock mass during a period of about two years, which corresponds to about twenty years of full-scale operation. Geological features of the rock around each experiment have been mapped carefully, and temperatures, stresses and displacements induced in the rock by heating have been calculated in advance of the experiments. Some 800 different measurements are recorded at frequent intervals by a computer system situated underground. These data can be compared at any time with predictions made earlier on video display units underground

Is torrefaction of polysaccharides-rich biomass equivalent to carbonization of lignin-rich biomass?

Science.gov (United States)

Bilgic, E; Yaman, S; Haykiri-Acma, H; Kucukbayrak, S

2016-01-01

Waste biomass species such as lignin-rich hazelnut shell (HS) and polysaccharides-rich sunflower seed shell (SSS) were subjected to torrefaction at 300°C and carbonization at 600°C under nitrogen. The structural variations in torrefied and carbonized biomasses were compared. Also, the burning characteristics under dry air and pure oxygen (oxy-combustion) conditions were investigated. It was concluded that the effects of carbonization on HS are almost comparable with the effects of torrefaction on SSS in terms of devolatilization and deoxygenation potentials and the increases in carbon content and the heating value. Consequently, it can be proposed that torrefaction does not provide efficient devolatilization from the lignin-rich biomass while it is relatively more efficient for polysaccharides-rich biomass. Heat-induced variations in biomass led to significant changes in the burning characteristics under both burning conditions. That is, low temperature reactivity of biomass reduced considerably and the burning shifted to higher temperatures with very high burning rates. Copyright © 2015 Elsevier Ltd. All rights reserved.

High-Efficiency Small-Scale Combined Heat and Power Organic Binary Rankine Cycles

OpenAIRE

Costante Mario Invernizzi; Nadeem Ahmed Sheikh

2018-01-01

Small-CHP (Combined Heat and Power) systems are generally considered a valuable technological option to the conventional boilers, in a technology developed context. If small-CHP systems are associated with the use of renewable energies (biomass, for example) they could play an important role in distributed generation even in developing countries or, in any case, where there are no extensive electricity networks. Traditionally the considered heat engines for micro- or mini-CHP are: the gas eng...

Differential Response to Heat Stress in Outer and Inner Onion Bulb Scales.

Science.gov (United States)

Galsurker, Ortal; Doron-Faigenboim, Adi; Teper-Bamnolker, Paula; Daus, Avinoam; Lers, Amnon; Eshel, Dani

2018-05-18

Brown protective skin formation in onion bulbs can be induced by rapid postharvest heat treatment. Onions that were peeled to different depths and were exposed to heat stress showed that only the outer scale formed dry brown skin, whereas the inner scales maintained high water content and did not change color. Our results reveal that browning of the outer scale during heat treatment is due to an enzymatic process that is associated with high levels of oxidation components, such as peroxidase and quercetin glucoside. De-novo transcriptome analysis revealed differential molecular responses of the outer and inner scales to the heat stress. Genes involved in lipid metabolism, oxidation pathways and cell-wall modification were highly expressed in the outer scale during heating. Defense-response-related genes such as those encoding heat-shock proteins, antioxidative stress defense or production of osmoprotectant metabolites were mostly induced in the inner scale in response to the heat exposure. These transcriptomic data led to a conceptual model that suggests sequential processes for browning development and desiccation of the outer scales versus processes associated with defense response and heat tolerance in the inner scale. Thus, the observed physiological differences between the outer and inner scales is supported by the identified molecular differences.

Importance of biomass energy sources for Turkey

International Nuclear Information System (INIS)

Demirbas, Ayhan

2008-01-01

Various agricultural residues such as grain dust, crop residues and fruit tree residues are available in Turkey as the sources of biomass energy. Among the biomass energy sources, fuelwood seems to be one of the most interesting because its share of the total energy production of Turkey is high at 21% and the techniques for converting it to useful energy are not necessarily sophisticated. Selection of a particular biomass for energy requirements is influenced by its availability, source and transportation cost, competing uses and prevalent fossil fuel prices. Utilization of biomass is a very attractive energy resource, particularly for developing countries since biomass uses local feedstocks and labor. Like many developing countries, Turkey relies on biomass to provide much of its energy requirement. More efficient use of biomass in producing energy, both electrical and thermal, may allow Turkey to reduce petroleum imports, thus affecting its balance of payments dramatically. Turkey has always been one of the major agricultural countries in the world. The importance of agriculture is increasing due to biomass energy being one of the major resources in Turkey. Biomass waste materials can be used in Turkey to provide centralized, medium- and large-scale production of process heat for electricity production. Turkey's first biomass power project is under development in Adana province, at an installed capacity of 45 MW. Two others, at a total capacity of 30 MW, are at the feasibility study stage in Mersin and Tarsus provinces. Electricity production from biomass has been found to be a promising method in the nearest future in Turkey

Evaluation of Hybrid Power Plants using Biomass, Photovoltaics and Steam Electrolysis for Hydrogen and Power Generation

Science.gov (United States)

Petrakopoulou, F.; Sanz, J.

2014-12-01

Steam electrolysis is a promising process of large-scale centralized hydrogen production, while it is also considered an excellent option for the efficient use of renewable solar and geothermal energy resources. This work studies the operation of an intermediate temperature steam electrolyzer (ITSE) and its incorporation into hybrid power plants that include biomass combustion and photovoltaic panels (PV). The plants generate both electricity and hydrogen. The reference -biomass- power plant and four variations of a hybrid biomass-PV incorporating the reference biomass plant and the ITSE are simulated and evaluated using exergetic analysis. The variations of the hybrid power plants are associated with (1) the air recirculation from the electrolyzer to the biomass power plant, (2) the elimination of the sweep gas of the electrolyzer, (3) the replacement of two electric heaters with gas/gas heat exchangers, and (4) the replacement two heat exchangers of the reference electrolyzer unit with one heat exchanger that uses steam from the biomass power plant. In all cases, 60% of the electricity required in the electrolyzer is covered by the biomass plant and 40% by the photovoltaic panels. When comparing the hybrid plants with the reference biomass power plant that has identical operation and structure as that incorporated in the hybrid plants, we observe an efficiency decrease that varies depending on the scenario. The efficiency decrease stems mainly from the low effectiveness of the photovoltaic panels (14.4%). When comparing the hybrid scenarios, we see that the elimination of the sweep gas decreases the power consumption due to the elimination of the compressor used to cover the pressure losses of the filter, the heat exchangers and the electrolyzer. Nevertheless, if the sweep gas is used to preheat the air entering the boiler of the biomass power plant, the efficiency of the plant increases. When replacing the electric heaters with gas-gas heat exchangers, the

Marine biomass power plant using methane fermentation

Energy Technology Data Exchange (ETDEWEB)

Matsui, T.; Saito, H.; Amano, T.; Sugawara, H.; Seki, T.; Abe, T. [Technology Research Inst., Tokyo Gas Co. Ltd., Tokyo (Japan)

2004-07-01

This study presented an effective way to produce biogas from the large quantities of seaweed waste in Japan. A large-scale marine biomass pilot plant was built to produce biogas from marine biomass. Methane fermentation was the process used to produce biogas from Laminaria sp. The maximum treating capacity of the pilot plant is 1 ton of seaweed per day. The pilot plant includes a pretreatment facility, fermentation, biogas storage and power generation. The maximum methane yield from the biomass plant is 22 cubic ton-seaweed. The purified biogas has generated 10 kW of electricity and 23 kW of heat. The biogas was also mixed with natural gas for use in a gas engine generator. The engine operation remained stable despite changes in quantity and composition of the collected biogas caused by changes with the source of biomass and sea conditions. The thermal efficiency of the gas engine running on mixed biogas and natural gas was more than 10 per cent higher than an engine running on biogas fuel alone. 4 refs., 2 tabs., 3 figs.

Quinault Indian Nation Comprehensive Biomass Strategic Planning Project

Energy Technology Data Exchange (ETDEWEB)

Cardenas, Jesus [American Community Enrichment, Elma, WA (United States)

2015-03-31

The overall purposes of the Quinault Indian Nation’s Comprehensive Biomass Strategic Planning Project were to: (1) Identify and confirm community and tribal energy needs; (2) Conducting an inventory of sustainable biomass feedstock availability; (3) Development of a biomass energy vision statement with goals and objectives; (4) Identification and assessment of biomass options for both demand-side and supply side that are viable to the Quinault Indian Nation (QIN); and (5) Developing a long-term biomass strategy consistent with the long-term overall energy goals of the QIN. This Comprehensive Biomass Strategic Planning Project is consistent with the QIN’s prior two-year DOE Renewable Energy Study from 2004 through 2006. That study revealed that the most viable options to the QIN’s renewable energy options were biomass and energy efficiency best practices. QIN's Biomass Strategic Planning Project is focused on using forest slash in chipped form as feedstock for fuel pellet manufacturing in support of a tribal biomass heating facility. This biomass heating facility has been engineered and designed to heat existing tribal facilities as well as tribal facilities currently being planned including a new K-12 School.

A Comparison of Producer Gas, Biochar, and Activated Carbon from Two Distributed Scale Thermochemical Conversion Systems Used to Process Forest Biomass

Directory of Open Access Journals (Sweden)

Nathaniel Anderson

2013-01-01

Full Text Available Thermochemical biomass conversion systems have the potential to produce heat, power, fuels and other products from forest biomass at distributed scales that meet the needs of some forest industry facilities. However, many of these systems have not been deployed in this sector and the products they produce from forest biomass have not been adequately described or characterized with regards to chemical properties, possible uses, and markets. This paper characterizes the producer gas, biochar, and activated carbon of a 700 kg h−1 prototype gasification system and a 225 kg h−1 pyrolysis system used to process coniferous sawmill and forest residues. Producer gas from sawmill residues processed with the gasifier had higher energy content than gas from forest residues, with averages of 12.4 MJ m−3 and 9.8 MJ m−3, respectively. Gases from the pyrolysis system averaged 1.3 MJ m−3 for mill residues and 2.5 MJ m−3 for forest residues. Biochars produced have similar particle size distributions and bulk density, but vary in pH and carbon content. Biochars from both systems were successfully activated using steam activation, with resulting BET surface area in the range of commercial activated carbon. Results are discussed in the context of co-locating these systems with forest industry operations.

Scaling-up the biomass production of Cymbopogon citratus L. in temporary immersion system

Directory of Open Access Journals (Sweden)

Elisa Quiala

2014-04-01

Full Text Available Shoot-tips, collected from greenhouse-grown plants of Cymbopogon citratus L. (lemmon grass, were incubated on a semi-solid Murashige and Skoog (MS medium with 30% (w/v sucrose, and supplemented with 0.89 µM 6-benzyladenine (BA. After three weeks of culture shoots were individualized and then inoculated in 10 litres temporary immersion system (TIS containing 3 litres of the same basal MS liquid medium. The effects of three immersion frequency (immersion every 12, 6 and 4 hours on the production of biomass were studied. Three inoculum densities (forty, fifty and sixty shoots/TIS were also tested. The biomass growth was inûuenced by the immersion frequency. The highest proliferation rate (17.3 shoots/explants and the plant length (45.2 cm were obtained in plants immersed every 4 h. Also, the fresh and dry biomass weight (153.4 gFW and 24.8 gDW, respectively were higher in this treatment. The maximum biomass accumulation (185.2 gFW and 35.2 gDW was achieved after 30 days of culture when an inoculum density of 60 explants per TIS was used. For the first time, biomass of C. citratus has been produced in10 litres TIS. These results represent the first step in the scaling-up the biomass production of this medicinal plant in large temporary immersion bioreactors. Key words: automation, biomass growth, lemmon grass medicinal plant, tissue culture

Temperature and heat flux scaling laws for isoviscous, infinite Prandtl number mixed heating convection.

Science.gov (United States)

Vilella, Kenny; Deschamps, Frederic

2018-04-01

Thermal evolution of terrestrial planets is controlled by heat transfer through their silicate mantles. A suitable framework for modelling this heat transport is a system including bottom heating (from the core) and internal heating, e.g., generated by secular cooling or by the decay of radioactive isotopes. The mechanism of heat transfer depends on the physical properties of the system. In systems where convection is able to operate, two different regimes are possible depending on the relative amount of bottom and internal heating. For moderate internal heating rates, the system is composed of active hot upwellings and cold downwellings. For large internal heating rates, the bottom heat flux becomes negative and the system is only composed of active cold downwellings. Here, we build theoretical scaling laws for both convective regimes following the approach of Vilella & Kaminski (2017), which links the surface heat flux and the temperature jump across both the top and bottom thermal boundary layer (TBL) to the Rayleigh number and the dimensionless internal heating rate. Theoretical predictions are then verified against numerical simulations performed in 2D and 3D-Cartesian geometry, and covering a large range of the parameter space. Our theoretical scaling laws are more successful in predicting the thermal structure of systems with large internal heating rates than that of systems with no or moderate internal heating. The differences between moderate and large internal heating rates are interpreted as differences in the mechanisms generating thermal instabilities. We identified three mechanisms: conductive growth of the TBL, instability impacting, and TBL erosion, the last two being present only for moderate internal heating rates, in which hot plumes are generated at the bottom of the system and are able to reach the surface. Finally, we apply our scaling laws to the evolution of the early Earth, proposing a new model for the cooling of the primordial magma ocean

Understanding Biomass Ignition in Power Plant Mills

DEFF Research Database (Denmark)

Schwarzer, Lars; Jensen, Peter Arendt; Glarborg, Peter

2017-01-01

. This is not very well explained by apply-ing conventional thermal ignition theory. An experimental study at lab scale, using pinewood as an example fuel, was conducted to examine self-heating and self-ignition. Supplemental experiments were performed with bituminous coal. Instead of characterizing ignition......Converting existing coal fired power plants to biomass is a readily implemented strategy to increase the share of renewable energy. However, changing from one fuel to another is not straightforward: Experience shows that wood pellets ignite more readily than coal in power plant mills or storages...... temperature in terms of sample volume, mass-scaling seems more physically correct for the self-ignition of solids. Findings also suggest that the transition between self-heating and self-ignition is controlled both by the availability of reactive material and temperature. Comparison of experiments at 20...

Regional processes in mangrove ecosystems: Spatial scaling relationships, biomass, and turnover rates following catastrophic disturbance

Science.gov (United States)

Ward, G.A.; Smith, T. J.; Whelan, K.R.T.; Doyle, T.W.

2006-01-01

Physiological processes and local-scale structural dynamics of mangroves are relatively well studied. Regional-scale processes, however, are not as well understood. Here we provide long-term data on trends in structure and forest turnover at a large scale, following hurricane damage in mangrove ecosystems of South Florida, U.S.A. Twelve mangrove vegetation plots were monitored at periodic intervals, between October 1992 and March 2005. Mangrove forests of this region are defined by a -1.5 scaling relationship between mean stem diameter and stem density, mirroring self-thinning theory for mono-specific stands. This relationship is reflected in tree size frequency scaling exponents which, through time, have exhibited trends toward a community average that is indicative of full spatial resource utilization. These trends, together with an asymptotic standing biomass accumulation, indicate that coastal mangrove ecosystems do adhere to size-structured organizing principles as described for upland tree communities. Regenerative dynamics are different between areas inside and outside of the primary wind-path of Hurricane Andrew which occurred in 1992. Forest dynamic turnover rates, however, are steady through time. This suggests that ecological, more-so than structural factors, control forest productivity. In agreement, the relative mean rate of biomass growth exhibits an inverse relationship with the seasonal range of porewater salinities. The ecosystem average in forest scaling relationships may provide a useful investigative tool of mangrove community biomass relationships, as well as offer a robust indicator of general ecosystem health for use in mangrove forest ecosystem management and restoration. ?? Springer 2006.

Torrefaction of biomass. Final report

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-05-15

occurring even at biomass torrefied at 300 deg. C. Thus it cannot be concluded if pellets of torrefied materials can be stored outside or not. Due to the fact that the densification process will also have big influence on this property and full scale testing with more materials is required before this can be concluded. Densification of torrefied material was tested in both bench scale as well as lab scale pellet presses and revealed larger challenges than expected. Torrefied material reveals a much higher friction, internal between particles as well as external with the die surface, than untreated biomass does and requires thus higher amounts of energy to compress and push through the dies. Moreover, due to that the chemistry of the binding agents in the biomass is altered by the heat treatment, it is also more challenging to produce pellets with high quality. Elevated die temperatures of above {approx}190 deg. C and usage of lubricating additives such as rape seed oil was shown to clearly improve the pelletisation properties, but more research and optimisation is necessary in the future. While grindability and moisture uptake are important for the usage and storage at the power plants, the densification of torrefied is important for the transport to the plant as it is necessary for increasing the energy density. Due to that devolatilization creates cavities in the material the energy density on a volume bases (GJ/m{sup 3}) is actually lowered during torrefaction. But the remaining torrefied biomass material does have a higher energy density on a mass basis (GJ/kg), and therefore subsequent densification by pelletisation will significantly increase it energy density above that of not treated biomass also on a volume bases. Due to the fact that transport of solid fuels on ships is limited by volume rather that mass, this property is important for the economics of the supply chain. (LN)

Heat pipes for ground heating and cooling

Energy Technology Data Exchange (ETDEWEB)

Vasiliev, L L

1988-01-01

Different versions of heat pipe ground heating and cooling devices are considered. Solar energy, biomass, ground stored energy, recovered heat of industrial enterprises and ambient cold air are used as energy and cold sources. Heat pipe utilization of air in winter makes it possible to design accumulators of cold and ensures deep freezing of ground in order to increase its mechanical strength when building roadways through the swamps and ponds in Siberia. Long-term underground heat storage systems are considered, in which the solar and biomass energy is accumulated and then transferred to heat dwellings and greenhouses, as well as to remove snow from roadways with the help of heat pipes and solar collectors.

Integrated biomass gasification using the waste heat from hot slags: Control of syngas and polluting gas releases

International Nuclear Information System (INIS)

Sun, Yongqi; Seetharaman, Seshadri; Liu, Qianyi; Zhang, Zuotai; Liu, Lili; Wang, Xidong

2016-01-01

In this study, the thermodynamics of a novel strategy, i.e., biomass/CO 2 gasification integrated with heat recovery from hot slags in the steel industry, were systemically investigated. Both the target syngas yield and the polluting gas release were considered where the effect of gasifying conditions including temperature, pressure and CO 2 reacted was analyzed and then the roles of hot slags were further clarified. The results indicated that there existed an optimum temperature for the maximization of H 2 production. Compared to blast furnace slags, steel slags remarkably increased the CO yield at 600–1400 °C due to the existence of iron oxides and decreased the S-containing gas releases at 400–700 °C, indicating potential desulfurizing ability. The identification of biomass/CO 2 gasification thermodynamics in presence of slags could thus provide important clues not only for the deep understanding of biomass gasification but also for the industrial application of this emerging strategy from the viewpoint of syngas optimization and pollution control. - Highlights: • Biomass/CO 2 gasification was integrated with the heat recovery from hot slags. • Both syngas yield and polluting gas release during gasification were determined. • There existed an optimum temperature for the maximization of H 2 production. • Steel slags increased CO yield at 600–1400 °C due to the existence of iron oxides. • Steel slags remarkably decreased the releases of S-containing gas at 400–700 °C.

News from heat-pump research - Large-scale heat pumps, components, heat pumps and solar heating; News aus der Waermepumpen-Forschung - Gross-Waermepumpen, Komponenten, Waermepumpe und Solar

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-06-15

These proceedings summarise the presentations made at the 16{sup th} annual meeting held by the Swiss Federal Office of Energy's Heat Pump Research Program in Burgdorf, Switzerland. The proceedings include contributions on large-scale heat pumps, components and the activities of the heat pump promotion society. A summary of targets and trends in energy research in general is presented and an overview of the heat pump market in 2009 and future perspectives is given. International work within the framework of the International Energy Agency's heat pump group is reviewed, including solar - heat pump combinations. Field-monitoring and the analysis of large-scale heat pumps are discussed and the importance of the use of correct concepts in such installations is stressed. Large-scale heat pumps with carbon dioxide as working fluid are looked at, as are output-regulated air/water heat pumps. Efficient system solutions with heat pumps used both to heat and to cool are discussed. Deep geothermal probes and the potential offered by geothermal probes using carbon dioxide as a working fluid are discussed. The proceedings are rounded off with a list of useful addresses.

Electron Heating at Kinetic Scales in Magnetosheath Turbulence

International Nuclear Information System (INIS)

Chasapis, Alexandros; Matthaeus, W. H.; Parashar, T. N.; LeContel, O.; Retinò, A.; Breuillard, H.; Khotyaintsev, Y.; Vaivads, A.; Eriksson, E.; Lavraud, B.; Moore, T. E.; Burch, J. L.; Torbert, R. B.; Chutter, M.; Needell, J.; Lindqvist, P.-A.; Marklund, G.; Ergun, R. E.; Goodrich, K. A.; Wilder, F. D.

2017-01-01

We present a statistical study of coherent structures at kinetic scales, using data from the Magnetospheric Multiscale mission in the Earth’s magnetosheath. We implemented the multi-spacecraft partial variance of increments (PVI) technique to detect these structures, which are associated with intermittency at kinetic scales. We examine the properties of the electron heating occurring within such structures. We find that, statistically, structures with a high PVI index are regions of significant electron heating. We also focus on one such structure, a current sheet, which shows some signatures consistent with magnetic reconnection. Strong parallel electron heating coincides with whistler emissions at the edges of the current sheet.

Biomass gasification systems for residential application: An integrated simulation approach

International Nuclear Information System (INIS)

Prando, Dario; Patuzzi, Francesco; Pernigotto, Giovanni; Gasparella, Andrea; Baratieri, Marco

2014-01-01

The energy policy of the European member States is promoting high-efficiency cogeneration systems by means of the European directive 2012/27/EU. Particular facilitations have been implemented for the small-scale and micro-cogeneration units. Furthermore, the directive 2010/31/EU promotes the improvement of energy performance of buildings and use of energy from renewable sources for the building sector. In this scenario, systems based on gasification are considered a promising technological solution when dealing with biomass and small scale systems. In this paper, an integrated approach has been implemented to assess the energy performance of combined heat and power (CHP) systems based on biomass gasification and installed in residential blocks. The space-heating loads of the considered building configurations have been simulated by means of EnergyPlus. The heat load for domestic hot water demand has been calculated according to the average daily profiles suggested by the Italian and European technical standards. The efficiency of the whole CHP system has been evaluated supplementing the simulation of the gasification stage with the energy balance of the cogeneration set (i.e., internal combustion engine) and implementing the developed routines in the Matlab-Simulink environment. The developed model has been used to evaluate the primary energy saving (PES) of the CHP system compared to a reference case of separate production of heat and power. Economic analyses are performed either with or without subsidizations for the generated electricity. The results highlight the capability of the integrated approach to estimate both energy and economic performances of CHP systems applied to the residential context. Furthermore, the importance of the generated heat valorisation and the proper system sizing have been discussed. - Highlights: • CHP system based on biomass gasification to meet household energy demand is studied. • Influence of CHP size and operation time on

Biomass fuelled indirect fired micro turbine

Energy Technology Data Exchange (ETDEWEB)

Pritchard, D.

2005-07-01

This report summarises the findings of a project to further develop and improve a system based on the Bowman TG50 50kWe turbine and a C3(S) combustor with a high temperature heat exchanger for the production of electricity from biomass. Details are given of the specific aims of the project, the manufacture of a new larger biomass combustor, the development of startup and shutdown procedures, waste heat recuperation, adaption of a PC-based mathematical model, and capital equipment costs. The significant levels of carbon emission savings and the commercial prospects of the biomass generator gas turbine combined heat and power (CHP) system are considered, and recommendations are presented.

Application of biogas for combined heat and power production in the rural region

International Nuclear Information System (INIS)

Kozak, T.; Majchrzycka, A.

2009-01-01

The paper discusses combined production of heat and power (CHP) from biogas in a small-scale power plant placed in the rural region. Based on power and heat demands of the rural region and biomass supply, the CHP system was selected. Keywords: biogas, cogeneration

Second Generation Gaseous Biofuels: from Biomass to Gas Grid

International Nuclear Information System (INIS)

Guerrini, O.; Perrin, M.; Marchand, B.; Prieur-Vernat, A.

2013-01-01

Gaseous biofuels and biomethane production by thermochemical pathway has many assets and, already, it should be seen as an essential component of future French and European energy panorama by 2020. As a biomass gasification process is used, a very wide range of biomass is accessible, guaranteeing a significant development potential of the sector. Because of the inherent advantages of the methanation reaction, methanation processes have very high overall energy efficiency, today comparable to other technologies for energy recovery from biomass. Moreover, these can be further enhanced by a waste heat valorization. The existence of technology adapted to installations of medium size (20-80 MW biomethane) promotes strong integration in the local area and is exemplary in a framework of sustainable development. Most of the steps of the process of biomethane production from biomass are at present commercially available. However, the technical feasibility of the whole production line of biomethane was not demonstrated to an industrial scale yet. (authors)

Thermal distillation system utilizing biomass energy burned in stove by means of heat pipe

Directory of Open Access Journals (Sweden)

Hiroshi Tanaka

2016-09-01

Full Text Available A thermal distillation system utilizing a part of the thermal energy of biomass burned in a stove during cooking is proposed. The thermal energy is transported from the stove to the distiller by means of a heat pipe. The distiller is a vertical multiple-effect diffusion distiller, in which a number of parallel partitions in contact with saline-soaked wicks are set vertically with narrow gaps of air. A pilot experimental apparatus was constructed and tested with a single-effect and multiple-effect distillers to investigate primarily whether a heat pipe can transport thermal energy adequately from the stove to the distiller. It was found that the temperatures of the heated plate and the first partition of the distiller reached to about 100 °C and 90 °C, respectively, at steady state, showing that the heat pipe works sufficiently. The distilled water obtained was about 0.75 and 1.35 kg during the first 2 h of burning from a single-effect and multiple-effect distillers, respectively.

A model for allometric scaling of mammalian metabolism with ambient heat loss

KAUST Repository

Kwak, Ho Sang

2016-02-02

Background Allometric scaling, which represents the dependence of biological trait or process relates on body size, is a long-standing subject in biological science. However, there has been no study to consider heat loss to the ambient and an insulation layer representing mammalian skin and fur for the derivation of the scaling law of metabolism. Methods A simple heat transfer model is proposed to analyze the allometry of mammalian metabolism. The present model extends existing studies by incorporating various external heat transfer parameters and additional insulation layers. The model equations were solved numerically and by an analytic heat balance approach. Results A general observation is that the present heat transfer model predicted the 2/3 surface scaling law, which is primarily attributed to the dependence of the surface area on the body mass. External heat transfer effects introduced deviations in the scaling law, mainly due to natural convection heat transfer which becomes more prominent at smaller mass. These deviations resulted in a slight modification of the scaling exponent to a value smaller than 2/3. Conclusion The finding that additional radiative heat loss and the consideration of an outer insulation fur layer attenuate these deviation effects and render the scaling law closer to 2/3 provides in silico evidence for a functional impact of heat transfer mode on the allometric scaling law in mammalian metabolism.

Small-Scale Pellet Boiler with Thermoelectric Generator

Energy Technology Data Exchange (ETDEWEB)

Moser, Wilhelm; Friedl, Guenther; Haslinger, Walter [Austrian Bioenergy Centre GmbH, Wieselburg (Austria); Hofbauer, Hermann [Vienna Univ. of Technology (Austria). Inst. of Chemical Engineering

2006-07-15

Pellet burners need auxiliary electrical power to provide CO{sub 2}-balanced heat in a comfortable and environment-friendly way. The idea is to produce this and some extra electricity within the furnace in order to save resources and to gain operation reliability and independency. Thermoelectric generators (TEGs) allow the direct conversion of heat to electrical power to a certain extent. They have the advantages of a maintenance-free long life and soundless operation without moving parts or any working fluid. A novel kind of decentralised small-scale biomass-based combined heat and power generation will be developed. The basic system allows grid-independent operation of automatically running biomass furnaces including fuel delivery from storage and circulating the cooling respectively heating water or air. The advanced system also provides electricity for network supply or for other electrical devices and is an additional benefit.

Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

DEFF Research Database (Denmark)

Rudra, Souman

alternative by upgrading existing district heating plant. It provides a generic modeling framework to design flexible energy system in near future. These frameworks address the three main issues arising in the planning and designing of energy system: a) socio impact at both planning and proses design level; b...... in this study. The overall aim of this work is to provide a complete assessment of the technical potential of biomass gasification for local heat and power supply in Denmark and replace of natural gas for the production. This study also finds and defines the future areas of research in the gasification......, it possible to lay a foundation for future gasification based power sector to produce flexible output such as electricity, heat, chemicals or bio-fuels by improving energy system of existing DHP(district heating plant) integrating gasification technology. The present study investigate energy system...

CFD-supported development of small-scale biomass furnaces; CFD-gestuetzte Entwicklung von Biomassefeuerungen im kleinen Leistungsbereich

Energy Technology Data Exchange (ETDEWEB)

Scharler, R. [Bios Bioenergiesystem GmbH, Graz (Austria); Obernberger, I. [Technische Univ. Eindhoven (Netherlands). Thermochemische Biomassekonversion; Weissinger, A. [Oesterreichische Kraft und Waerme aus Biomasse GmbH (KWB), St. Margarethen/Raab (Austria). Bereich Forschung und Entwicklung; Schmidt, W. [Oesterreichische Kraft und Waerme aus Biomasse GmbH (KWB), St. Margarethen/Raab (Austria). Bereich Produktentwicklung, Umwelt- und Informationsmanagement

2005-07-01

Despite the complexity of solid biomass combustion, the Bios Bioenergiesysteme GmbH, Graz, Austria, has successfully developed and optimised several biomass furnaces in the range of 500 kW to 30 MW based on CFD (Computational Fluid Dynamics). A project carried out in co-operation with the KWB Kraft und Waerme aus Biomasse GmbH, St. Margarethen, Austria, demonstrates the application of CFD for the efficient and improved design of small-scale furnaces for solid biofuels like pellets and wood chips as basis for a series production. (orig.)

Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

Energy Technology Data Exchange (ETDEWEB)

Maghzi, Shawn; Subramanian, Ramanathan; Rizeq, George; Singh, Surinder; McDermott, John; Eiteneer, Boris; Ladd, David; Vazquez, Arturo; Anderson, Denise; Bates, Noel

2011-09-30

The U.S. Department of Energy‘s National Energy Technology Laboratory (DOE NETL) is exploring affordable technologies and processes to convert domestic coal and biomass resources to high-quality liquid hydrocarbon fuels. This interest is primarily motivated by the need to increase energy security and reduce greenhouse gas emissions in the United States. Gasification technologies represent clean, flexible and efficient conversion pathways to utilize coal and biomass resources. Substantial experience and knowledge had been developed worldwide on gasification of either coal or biomass. However, reliable data on effects of blending various biomass fuels with coal during gasification process and resulting syngas composition are lacking. In this project, GE Global Research performed a complete characterization of the gas, liquid and solid products that result from the co-gasification of coal/biomass mixtures. This work was performed using a bench-scale gasifier (BSG) and a pilot-scale entrained flow gasifier (EFG). This project focused on comprehensive characterization of the products from gasifying coal/biomass mixtures in a high-temperature, high-pressure entrained flow gasifier. Results from this project provide guidance on appropriate gas clean-up systems and optimization of operating parameters needed to develop and commercialize gasification technologies. GE‘s bench-scale test facility provided the bulk of high-fidelity quantitative data under temperature, heating rate, and residence time conditions closely matching those of commercial oxygen-blown entrained flow gasifiers. Energy and Environmental Research Center (EERC) pilot-scale test facility provided focused high temperature and pressure tests at entrained flow gasifier conditions. Accurate matching of syngas time-temperature history during cooling ensured that complex species interactions including homogeneous and heterogeneous processes such as particle nucleation, coagulation, surface condensation, and

Product Characterization for Entrained Flow Coal/Biomass Co-Gasification

Energy Technology Data Exchange (ETDEWEB)

Maghzi, Shawn [General Electric Global Research, Niskayuna, NY (United States); Subramanian, Ramanathan [General Electric Global Research, Niskayuna, NY (United States); Rizeq, George [General Electric Global Research, Niskayuna, NY (United States); Singh, Surinder [General Electric Global Research, Niskayuna, NY (United States); McDermott, John [General Electric Global Research, Niskayuna, NY (United States); Eiteneer, Boris [General Electric Global Research, Niskayuna, NY (United States); Ladd, David [General Electric Global Research, Niskayuna, NY (United States); Vazquez, Arturo [General Electric Global Research, Niskayuna, NY (United States); Anderson, Denise [General Electric Global Research, Niskayuna, NY (United States); Bates, Noel [General Electric Global Research, Niskayuna, NY (United States)

2011-12-11

The U.S. Department of Energy's National Energy Technology Laboratory (DOE NETL) is exploring affordable technologies and processes to convert domestic coal and biomass resources to high-quality liquid hydrocarbon fuels. This interest is primarily motivated by the need to increase energy security and reduce greenhouse gas emissions in the United States. Gasification technologies represent clean, flexible and efficient conversion pathways to utilize coal and biomass resources. Substantial experience and knowledge had been developed worldwide on gasification of either coal or biomass. However, reliable data on effects of blending various biomass fuels with coal during gasification process and resulting syngas composition are lacking. In this project, GE Global Research performed a complete characterization of the gas, liquid and solid products that result from the co-gasification of coal/biomass mixtures. This work was performed using a bench-scale gasifier (BSG) and a pilot-scale entrained flow gasifier (EFG). This project focused on comprehensive characterization of the products from gasifying coal/biomass mixtures in a high-temperature, high-pressure entrained flow gasifier. Results from this project provide guidance on appropriate gas clean-up systems and optimization of operating parameters needed to develop and commercialize gasification technologies. GE's bench-scale test facility provided the bulk of high-fidelity quantitative data under temperature, heating rate, and residence time conditions closely matching those of commercial oxygen-blown entrained flow gasifiers. Energy and Environmental Research Center (EERC) pilot-scale test facility provided focused high temperature and pressure tests at entrained flow gasifier conditions. Accurate matching of syngas time-temperature history during cooling ensured that complex species interactions including homogeneous and heterogeneous processes such as particle nucleation, coagulation, surface condensation

Foliage and Grass as Fuel Pellets–Small Scale Combustion of Washed and Mechanically Leached Biomass

Directory of Open Access Journals (Sweden)

Jan Hari Arti Khalsa

2016-05-01

Full Text Available The high contents of disadvantageous elements contained in non-woody biomass are known to cause problems during small and large scale combustion, typically resulting in a higher risk of slagging, corrosion, and increased emissions. Mechanically leaching the respective elements from the biomass through a sequence of process steps has proven to be a promising solution.The florafuel process used here is comprised of size reduction followed by washing and subsequent mechanical dewatering of the biomass. Densification of the upgraded biomass into standardized pellets (Ø 6mm enables an application in existing small-scale boilers. The presented combustion trials investigated the performance of pellets made from leached grass, foliage and a mixture of both in two small-scale boilers (<100 kWth with slightly different technology (moving grate versus water-cooled burner tube during a 4-h measurement period. Emissions were in accordance with German emissions standards except for NOx (threshold is 0.50 g/m3 in the case of pure grass pellets (0.51 g/m3 and particulate matter (PM in all but one case (foliage, 13–16 mg/m3. An electrostatic precipitator (ESP unit installed with one of the boilers successfully reduced PM emission of both the grass and mixture fuel below the threshold of 20 mg/m3 (all emission values refer to 13 vol.% O2, at standard temperature and pressure (STP. Bottom ash composition and grate temperature profiles were analyzed and discussed for one of the boilers.

The biomass

International Nuclear Information System (INIS)

Viterbo, J.

2011-01-01

Biomass comes mainly from forests and agriculture and is considered as a clean alternative energy that can be valorized as heat, power, bio-fuels and chemical products but its mass production is challenging in terms of adequate technology but also in terms of rethinking the use of lands. Forests can be managed to produce biomass but bio-fuels can also be generated from sea-weeds. Biomass appears very promising but on one hand we have to secure its supplying and assure its economical profitability and on another hand we have to assure a reasonable use of lands and a limited impact on the environment. The contribution of biomass to sustainable development depends on the balance between these 2 ends. (A.C.)

Exergy analysis of biomass-to-synthetic natural gas (SNG) process via indirect gasification of various biomass feedstock

NARCIS (Netherlands)

Vitasari, C.R.; Jurascik, M.; Ptasinski, K.J.

2011-01-01

This paper presents an exergy analysis of SNG production via indirect gasification of various biomass feedstock, including virgin (woody) biomass as well as waste biomass (municipal solid waste and sludge). In indirect gasification heat needed for endothermic gasification reactions is produced by

Biomass programme: Overview of the 2006 Swiss research programme; Programm Biomasse. Ueberblicksbericht zum Forschungsprogramm 2006

Energy Technology Data Exchange (ETDEWEB)

Binggeli, D.; Guggisberg, B.

2007-07-01

This report for the Swiss Federal Office of Energy (SFOE) reviews work done within the framework of the Swiss biomass research programme in 2006. The programme concentrates on the efficient conversion of biomass into heat, electrical power and motor fuels. Projects concerned with the optimisation of processes are reported on, including low-particle-emission systems, control systems for bivalent heating installations, use of demanding biomass fuels, combined pellets and solar heating systems and the elimination of ammonia emissions. In the material flow area, measurement campaigns, organic pollutants in compost, the effects of fermented wastes in agriculture and methane losses in biogas conditioning are reported on. New conversion technologies are reviewed, including hydro-thermal gasification, plant-oil fuelled combined heat and power units, flameless burners and catalytic direct liquefaction. In the area of basics, studies and concepts, eco-balances and life-cycle analyses are reported on; the production of synthetic natural gas and the influence of combustion particles are discussed and decentralised power generation from solid biomass is reported on. National and international co-operation is reviewed. The report is concluded with a review of eight pilot and demonstration projects, a review of work to be done in 2007 and a list of research and demonstration projects.

Technical and economic assessment of producing hydrogen by reforming syngas from the Battelle indirectly heated biomass gasifier

International Nuclear Information System (INIS)

Mann, M.K.

1995-08-01

The technical and economic feasibility of producing hydrogen from biomass by means of indirectly heated gasification and steam reforming was studied. A detailed process model was developed in ASPEN Plus trademark to perform material and energy balances. The results of this simulation were used to size and cost major pieces of equipment from which the determination of the necessary selling price of hydrogen was made. A sensitivity analysis was conducted on the process to study hydrogen price as a function of biomass feedstock cost and hydrogen production efficiency. The gasification system used for this study was the Battelle Columbus Laboratory (BCL) indirectly heated gasifier. The heat necessary for the endothermic gasification reactions is supplied by circulating sand from a char combustor to the gasification vessel. Hydrogen production was accomplished by steam reforming the product synthesis gas (syngas) in a process based on that used for natural gas reforming. Three process configurations were studied. Scheme 1 is the full reforming process, with a primary reformer similar to a process furnace, followed by a high temperature shift reactor and a low temperature shift reactor. Scheme 2 uses only the primary reformer, and Scheme 3 uses the primary reformer and the high temperature shift reactor. A pressure swing adsorption (PSA) system is used in all three schemes to produce a hydrogen product pure enough to be used in fuel cells. Steam is produced through detailed heat integration and is intended to be sold as a by-product

Biomass assessment and small scale biomass fired electricity generation in the Green Triangle, Australia

International Nuclear Information System (INIS)

Rodriguez, Luis C.; May, Barrie; Herr, Alexander; O'Connell, Deborah

2011-01-01

Coal fired electricity is a major factor in Australia's greenhouse gas emissions (GHG) emissions. The country has adopted a mandatory renewable energy target (MRET) to ensure that 20% of electricity comes from renewable sources by 2020. In order to support the MRET, a market scheme of tradable Renewable Energy Certificates (RECs) has been implemented since 2001. Generators using biomass from eligible sources are able to contribute to GHG emission reduction through the substitution of coal for electricity production and are eligible to create and trade RECs. This paper quantifies the potential biomass resources available for energy generation from forestry and agriculture in the Green Triangle, one of the most promising Australian Regions for biomass production. We analyse the cost of electricity generation using direct firing of biomass, and estimate the required REC prices to make it competitive with coal fired electricity generation. Major findings suggest that more than 2.6 million tonnes of biomass are produced every year within 200 km of the regional hub of Mount Gambier and biomass fired electricity is viable using feedstock with a plant gate cost of 46 Australian Dollars (AUD) per tonne under the current REC price of 34 AUD per MWh. These findings are then discussed in the context of regional energy security and existing targets and incentives for renewable energies. -- Highlights: → We assessed the biomass production in the Green Triangle. → 2.6 million tonnes of biomass per year are produced within 200 km from Mt Gambier. → Renewable Energy Certificates makes bioenergy competitive with coal electricity. → At a REC price of 34 AUD, biomass of up to 46 AUD/tonne might be used for bionergy

Biomass Assessment: A Question of Method and Expertise

International Nuclear Information System (INIS)

Thivolle-Cazat, A.; Le Net, E.; Labalette, F.; Marsac, S.

2013-01-01

Whereas the new stakes on lignocellulosic biomass are often demand-oriented (heat, electricity, biofuels, etc.) mainly through public policies, the new equilibrium will depend also on the supply-side. This supply has to be understood as socio-economic and environmental targets combining many topics: multi- resources (agriculture, forest, 'dedicated coppices', by-products and wastes), available/potential quantities and costs, localisation, replacement/substitution effects (activities, lands), and supply- side stakeholders' behaviours. Many initiatives have been launched to grasp those dimensions through projects (National Research Agency, French Environment and Energy Management Agency, etc.). Many figures exist on the biomass assessment aspect but they are not clear enough and not comparable due to differences in definitions, scopes, data, parameters, geographical levels, reporting units, time-scale, etc. Regarding the characterisation of biomass supply chains, evaluations are often incomplete and lack methodological references. This article aims to focus on methodological key points and barriers to overcome, in order to get a better evaluation and understanding of biomass mobilisation expected by potential users and public authorities. (authors)

Bio energy: Production of Biomass; Produksjon av biomasse

Energy Technology Data Exchange (ETDEWEB)

Noreng, Katrina; Indergaard, Mentz; Liodden, Ole Joergen; Hohle, Erik Eid; Sandberg, Eiliv

2001-07-01

This is Chapter 2 of the book ''Bio energy - Environment, technique and market''. Its main sections are: (1) Biomass resources in Norway, (2) The foundation - photosynthesis, (3) Biomass from forestry, (4) Biomass from peat lands, (5) Biomass from agriculture and (6) Biomass from lakes and sea. The exposition largely describes the conditions in Norway, where the use of bio energy can be increased from 15 TWh to 35 TWh using available technology. At present, water-borne heating systems are not extensively used in Norway and 30% of the biomass that is cut in the forests remains there as waste. Using this waste for energy generation would not only contribute to reduce the emission of greenhouse gases, but would often lead to improved forest rejuvenation. Use of a few per thousand of the Norwegian peat lands would produce 2 - 3 TWh. According to calculations, along the coast of Norway, there are at least 15 mill tonnes of kelp and sea tangle and these resources can be utilized in a sustainable way.

Pipelines : moving biomass and energy

Energy Technology Data Exchange (ETDEWEB)

Kumar, A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mechanical Engineering

2006-07-01

Moving biomass and energy through pipelines was presented. Field sourced biomass utilization for fuel was discussed in terms of competing cost factors; economies of scale; and differing fuel plant sizes. The cost versus scale in a bioenergy facility was illustrated in chart format. The transportation cost of biomass was presented as it is a major component of total biomass processing cost and is in the typical range of 25-45 per cent of total processing costs for truck transport of biomass. Issues in large scale biomass utilization, scale effects in transportation, and components of transport cost were identified. Other topics related to transportation issues included approaches to pipeline transport; cost of wood chips in pipeline transport; and distance variable cost of transporting wood chips by pipeline. Practical applications were also offered. In addition, the presentation provided and illustrated a model for an ethanol plant supplied by truck transport as well as a sample configuration for 19 truck based ethanol plants versus one large facility supplied by truck plus 18 pipelines. Last, pipeline transport of bio-oil and pipeline transport of syngas was discussed. It was concluded that pipeline transport can help in reducing congestion issues in large scale biomass utilization and that it can offer a means to achieve large plant size. Some current research at the University of Alberta on pipeline transport of raw biomass, bio-oil and hydrogen production from biomass for oil sands and pipeline transport was also presented. tabs., figs.

Integration of biomass fast pyrolysis and precedent feedstock steam drying with a municipal combined heat and power plant

International Nuclear Information System (INIS)

Kohl, Thomas; Laukkanen, Timo P.; Järvinen, Mika P.

2014-01-01

Biomass fast pyrolysis (BFP) is a promising pre-treatment technology for converting biomass to transport fuel and in the future also for high-grade chemicals. BFP can be integrated with a municipal combined heat and power (CHP) plant. This paper shows the influence of BFP integration on a CHP plant's main parameters and its effect on the energetic and environmental performance of the connected district heating network. The work comprises full- and part-load operation of a CHP plant integrated with BFP and steam drying. It also evaluates different usage alternatives for the BFP products (char and oil). The results show that the integration is possible and strongly beneficial regarding energetic and environmental performance. Offering the possibility to provide lower district heating loads, the operation hours of the plant can be increased by up to 57%. The BFP products should be sold rather than applied for internal use as this increases the district heating network's primary energy efficiency the most. With this integration strategy future CHP plants can provide valuable products at high efficiency and also can help to mitigate global CO 2 emissions. - Highlights: • Part load simulation of a cogeneration plant integrated with biomas fast pyrolysis. • Analysis of energetic and environmental performance. • Assessment of different uses of the pyrolysis products

Method for producing bio-fuel that integrates heat from carbon-carbon bond-forming reactions to drive biomass gasification reactions

Science.gov (United States)

Cortright, Randy D [Madison, WI; Dumesic, James A [Verona, WI

2011-01-18

A low-temperature catalytic process for converting biomass (preferably glycerol recovered from the fabrication of bio-diesel) to synthesis gas (i.e., H.sub.2/CO gas mixture) in an endothermic gasification reaction is described. The synthesis gas is used in exothermic carbon-carbon bond-forming reactions, such as Fischer-Tropsch, methanol, or dimethylether syntheses. The heat from the exothermic carbon-carbon bond-forming reaction is integrated with the endothermic gasification reaction, thus providing an energy-efficient route for producing fuels and chemicals from renewable biomass resources.

Design, scale-up, Six Sigma in processing different feedstocks in a fixed bed downdraft biomass gasifier

Science.gov (United States)

Boravelli, Sai Chandra Teja

This thesis mainly focuses on design and process development of a downdraft biomass gasification processes. The objective is to develop a gasifier and process of gasification for a continuous steady state process. A lab scale downdraft gasifier was designed to develop the process and obtain optimum operating procedure. Sustainable and dependable sources such as biomass are potential sources of renewable energy and have a reasonable motivation to be used in developing a small scale energy production plant for countries such as Canada where wood stocks are more reliable sources than fossil fuels. This thesis addresses the process of thermal conversion of biomass gasification process in a downdraft reactor. Downdraft biomass gasifiers are relatively cheap and easy to operate because of their design. We constructed a simple biomass gasifier to study the steady state process for different sizes of the reactor. The experimental part of this investigation look at how operating conditions such as feed rate, air flow, the length of the bed, the vibration of the reactor, height and density of syngas flame in combustion flare changes for different sizes of the reactor. These experimental results also compare the trends of tar, char and syngas production for wood pellets in a steady state process. This study also includes biomass gasification process for different wood feedstocks. It compares how shape, size and moisture content of different feedstocks makes a difference in operating conditions for the gasification process. For this, Six Sigma DMAIC techniques were used to analyze and understand how each feedstock makes a significant impact on the process.

Analysis and co-ordination of the activities concerning gasification of biomass. Summary country report, Denmark and Norway

International Nuclear Information System (INIS)

Stoholm, P.; Olsen, A.

1996-11-01

The analysis summarises the coordination of activities concerning the gasification of biomass in Denmark and Norway. The total quantity of available biomass for energy production in Denmark corresponds to ca. 115 PJ of which ca. 40% is utilized - and this constitutes ca. 6% of the country's total energy consumption. The resulting energy from biomass is currently mostly used for heating purposes utilizing small wood/straw household or farm stoves in addition to ca. 100 district heating systems. There is a tendency to use biomass fuels for electric power production as in the case of all major waste incineration plants and about 10 fully or partly wood/straw-fired cogeneration plants which are found within the range of 2 -20 MWe. A table shows details of all Danish biomass gasification plants and information is given on the types of biomass, under the titles of residue products and energy crops, most relevant to energy production in Denmark. Data is presented on the consumption of renewable energy in Denmark, recalculated in fuel equivalents, and Danish national energy policy and related legislation are described. Information on Norway's use of biomass as fuel is given under the headings of primary consumption, biomass sources and use, legislation, and brief evaluations of commercial gasification plants, pilot and demonstration plants, and laboratory plants and studies. It has recently been decided to speed up the development of small-scale gasification plants for combined heat and electricity production using biomass as fuel in Denmark. Total Norwegian energy consumption is 25% higher than Denmark's, and biomass fuels cover only 3.6% of this. (ARW) 32 refs

Conversion of biomass into energy source

International Nuclear Information System (INIS)

Antonescu, S.; Garjoaba, M.; Antonescu, A.

2005-01-01

This study assists the identification of possible application and markets of the CHP-plants in the NAS states, and forms the first part of a detailed study on economical and ecological prospects of small scale and large heat pipe reformers in NAS. It is well known that the energy strategy of the European Union, foresees the increase of the participation of the renewable energy from the total of the energy resources of the European Union, up to 12% in 2010. This participation is of a great importance for the adequate reduction of green house effect gases. From the energy production point of view it is proven the fact that in 2010 the production of renewable energy will be: electricity - 675 tWh; heat - 80 Mtoe (930 TWh). From the above mentioned energy demand, the biomass will cover: electricity - 230 TWh-34,1%; heat - 75 Mtoe (93,8%)

A national-scale remote sensing-based methodology for quantifying tidal marsh biomass to support "Blue Carbon" accounting

Science.gov (United States)

Byrd, K. B.; Ballanti, L.; Nguyen, D.; Simard, M.; Thomas, N.; Windham-Myers, L.; Castaneda, E.; Kroeger, K. D.; Gonneea, M. E.; O'Keefe Suttles, J.; Megonigal, P.; Troxler, T.; Schile, L. M.; Davis, M.; Woo, I.

2016-12-01

According to 2013 IPCC Wetlands Supplement guidelines, tidal marsh Tier 2 or Tier 3 accounting must include aboveground biomass carbon stock changes. To support this need, we are using free satellite and aerial imagery to develop a national scale, consistent remote sensing-based methodology for quantifying tidal marsh aboveground biomass. We are determining the extent to which additional satellite data will increase the accuracy of this "blue carbon" accounting. Working in 6 U.S. estuaries (Cape Cod, MA, Chesapeake Bay, MD, Everglades, FL, Mississippi Delta, LA, San Francisco Bay, CA, and Puget Sound, WA), we built a tidal marsh biomass dataset (n=2404). Landsat reflectance data were matched spatially and temporally with field plots using Google Earth Engine. We quantified percent cover of green vegetation, non-vegetation, and open water in Landsat pixels using segmentation of 1m National Agriculture Imagery Program aerial imagery. Sentinel-1A C-band backscatter data were used in Chesapeake, Mississippi Delta and Puget Sound. We tested multiple Landsat vegetation indices and Sentinel backscatter metrics in 30m scale biomass linear regression models by region. Scaling biomass by fraction green vegetation significantly improved biomass estimation (e.g. Cape Cod: R2 = 0.06 vs. R2 = 0.60, n=28). The best vegetation indices differed by region, though indices based on the shortwave infrared-1 and red bands were most predictive in the Everglades and the Mississippi Delta, while the soil adjusted vegetation index was most predictive in Puget Sound and Chesapeake. Backscatter metrics significantly improved model predictions over vegetation indices alone; consistently across regions, the most significant metric was the range in backscatter values within the green vegetation segment of the Landsat pixel (e.g. Mississippi Delta: R2 = 0.47 vs. R2 = 0.59, n=15). Results support using remote sensing of biomass stock change to estimate greenhouse gas emission factors in tidal

Biomass and Swedish energy policy

International Nuclear Information System (INIS)

Johansson, Bengt

2001-01-01

The use of biomass in Sweden has increased by 44% between 1990 and 1999. In 1999 it was 85 TWh, equivalent to 14% of the total Swedish energy supply. The existence of large forest industry and district heating systems has been an essential condition for this expansion. The tax reform in 1991 seems, however, to have been the most important factor responsible for the rapid bioenergy expansion. Through this reform, the taxation of fossil fuels in district heating systems increased by approximately 30-160%, depending on fuel, whereas bioenergy remained untaxed. Industry is exempted from the energy tax and pays reduced carbon tax. No tax is levied on fossil fuels used for electricity production. Investment grants have existed for biomass-based electricity production but these grants have not been large enough to make biomass-based electricity production economically competitive in a period of falling electricity prices. Despite this, the biomass-based electricity production has increased slightly between 1990 and 1999. A new taxation system aiming at a removal of the tax difference between the industry, district heating and electricity sectors has recently been analysed by the Swedish government. One risk with such a system is that it reduces the competitiveness for biomass in district heating systems as it seems unlikely that the taxes on fossil fuels in the industry and electricity sectors will increase to a level much higher than in other countries. A new system, based on green certificates, for supporting electricity from renewable energy sources has also been proposed by the government.

A laboratory-scale pretreatment and hydrolysis assay for determination of reactivity in cellulosic biomass feedstocks.

Science.gov (United States)

Wolfrum, Edward J; Ness, Ryan M; Nagle, Nicholas J; Peterson, Darren J; Scarlata, Christopher J

2013-11-14

The rapid determination of the release of structural sugars from biomass feedstocks is an important enabling technology for the development of cellulosic biofuels. An assay that is used to determine sugar release for large numbers of samples must be robust, rapid, and easy to perform, and must use modest amounts of the samples to be tested.In this work we present a laboratory-scale combined pretreatment and saccharification assay that can be used as a biomass feedstock screening tool. The assay uses a commercially available automated solvent extraction system for pretreatment followed by a small-scale enzymatic hydrolysis step. The assay allows multiple samples to be screened simultaneously, and uses only ~3 g of biomass per sample. If the composition of the biomass sample is known, the results of the assay can be expressed as reactivity (fraction of structural carbohydrate present in the biomass sample released as monomeric sugars). We first present pretreatment and enzymatic hydrolysis experiments on a set of representative biomass feedstock samples (corn stover, poplar, sorghum, switchgrass) in order to put the assay in context, and then show the results of the assay applied to approximately 150 different feedstock samples covering 5 different materials. From the compositional analysis data we identify a positive correlation between lignin and structural carbohydrates, and from the reactivity data we identify a negative correlation between both carbohydrate and lignin content and total reactivity. The negative correlation between lignin content and total reactivity suggests that lignin may interfere with sugar release, or that more mature samples (with higher structural sugars) may have more recalcitrant lignin. The assay presented in this work provides a robust and straightforward method to measure the sugar release after pretreatment and saccharification that can be used as a biomass feedstock screening tool. We demonstrated the utility of the assay by

Upgrading fuel properties of biomass by torrefaction

Energy Technology Data Exchange (ETDEWEB)

Lei Shang

2012-12-15

Torrefaction is a mild thermal (200 - 300 UC) treatment in an inert atmosphere, which is known to increase the energy density of biomass by evaporating water and a proportion of volatiles. In this work, the influence of torrefaction on the chemical and mechanical properties (grindability and hygroscopicity) of wood chips, wood pellets and wheat straw was investigated and compared. The mass loss during torrefaction was found to be a useful indicator for determining the degree of torrefaction. For all three biomass, higher torrefaction temperature or longer residence time resulted in higher mass loss, higher heating value, better grindability, and less moisture absorption. However, severe torrefaction conditions were found not necessary in order to save energy during grinding, since strain energy and grinding energy decreased tremendously in the first 5 - 25% anhydrous weight loss. By correlating the heating value and mass loss, it was found that wheat straw contained less heating value on mass basis than the other two fuels, but the fraction of energy retained in the torrefied sample as a function of mass loss was very similar for all three biomass. Gas products formed during torrefaction of three biomass were detected in situ by coupling mass spectrometer with a thermogravimetric analyzer (TGA). The main components were water, carbon monoxide, formic acid, formaldehyde, methanol, acetic acid, carbon dioxide, and methyl chloride. The cumulative releases of gas products from three biomass fuels at 300 UC for 1 h were compared, and water was found to be the dominant product during torrefaction. The degradation kinetics of wheat straw was studied in TGA by applying a two-step reaction in series model and taking the mass loss during the initial heating period into account. The model and parameters were proven to be able to predict the residual mass of wheat straw in a batch scale torrefaction reactor with different heating rates well. It means the mass yield of solids

Reducing life cycle greenhouse gas emissions of corn ethanol by integrating biomass to produce heat and power at ethanol plants

International Nuclear Information System (INIS)

Kaliyan, Nalladurai; Morey, R. Vance; Tiffany, Douglas G.

2011-01-01

A life-cycle assessment (LCA) of corn ethanol was conducted to determine the reduction in the life-cycle greenhouse gas (GHG) emissions for corn ethanol compared to gasoline by integrating biomass fuels to replace fossil fuels (natural gas and grid electricity) in a U.S. Midwest dry-grind corn ethanol plant producing 0.19 hm 3 y -1 of denatured ethanol. The biomass fuels studied are corn stover and ethanol co-products [dried distillers grains with solubles (DDGS), and syrup (solubles portion of DDGS)]. The biomass conversion technologies/systems considered are process heat (PH) only systems, combined heat and power (CHP) systems, and biomass integrated gasification combined cycle (BIGCC) systems. The life-cycle GHG emission reduction for corn ethanol compared to gasoline is 38.9% for PH with natural gas, 57.7% for PH with corn stover, 79.1% for CHP with corn stover, 78.2% for IGCC with natural gas, 119.0% for BIGCC with corn stover, and 111.4% for BIGCC with syrup and stover. These GHG emission estimates do not include indirect land use change effects. GHG emission reductions for CHP, IGCC, and BIGCC include power sent to the grid which replaces electricity from coal. BIGCC results in greater reductions in GHG emissions than IGCC with natural gas because biomass is substituted for fossil fuels. In addition, underground sequestration of CO 2 gas from the ethanol plant's fermentation tank could further reduce the life-cycle GHG emission for corn ethanol by 32% compared to gasoline.

Production of Solid sustainable Energy Carriers from biomass by means of TORrefaction (SECTOR)

Energy Technology Data Exchange (ETDEWEB)

Witt, Janet; Bienert, Kathrin [DBFZ Deutsches Biomasseforschungszentrum gemeinnuetzige GmbH, Leipzig (Germany). Bereich Bioenergiesysteme; Zwart, Robin; Kiel, Jaap; Englisch, Martin; Wojcik, Magdalena

2012-07-01

SECTOR is a large-scale European project with a strong consortium of over 20 partners from industry and science. The project is focussed on the further development of torrefaction-based technologies for the production of solid bioenergy carriers up to pilot-plant scale and beyond, and on supporting the market introduction of torrefaction-based bioenergy carriers as a commodity renewable solid fuel. The torrefaction of biomass materials is considered to be a very promising technology for the promotion of the large-scale implementation of bioenergy. During torrefaction biomass is heated up in the absence of oxygen to a temperature of 250-320 C. By combining torrefaction with pelletisation or briquetting, biomass materials can be converted into a high-energy-density commodity solid fuel or bioenergy carrier with improved behaviour in (long-distance) transport, handling and storage, and also with superior properties in many major end-use applications. Torrefaction has the potential to provide a significant contribution to an enlarged raw material portfolio for biomass fuel production inside Europe by including both agricultural and forestry biomass. In this way, the SECTOR project is expected to shorten the time-to-market of torrefaction technology and to promote market introduction within stringent sustainability boundary conditions. The European Union provides funding for this project within the Seventh Framework Programme. The project has a duration of 42 months and started in January 2012. (orig.)

Allothermal steam gasification of biomass in cyclic multi-compartment bubbling fluidized-bed gasifier/combustor - new reactor concept.

Science.gov (United States)

Iliuta, Ion; Leclerc, Arnaud; Larachi, Faïçal

2010-05-01

A new reactor concept of allothermal cyclic multi-compartment fluidized bed steam biomass gasification is proposed and analyzed numerically. The concept combines space and time delocalization to approach an ideal allothermal gasifier. Thermochemical conversion of biomass in periodic time and space sequences of steam biomass gasification and char/biomass combustion is simulated in which the exothermic combustion compartments provide heat into an array of interspersed endothermic steam gasification compartments. This should enhance unit heat integration and thermal efficiency and procure N(2)-free biosyngas with recourse neither to oxygen addition in steam gasification nor contact between flue and syngas. The dynamic, one-dimensional, multi-component, non-isothermal model developed for this concept accounts for detailed solid and gas flow dynamics whereupon gasification/combustion reaction kinetics, thermal effects and freeboard-zone reactions were tied. Simulations suggest that allothermal operation could be achieved with switch periods in the range of a minute supporting practical feasibility for portable small-scale gasification units. Copyright 2009 Elsevier Ltd. All rights reserved.

Liquid transportation fuels via large-scale fluidised-bed gasification of lignocellulosic biomass

Energy Technology Data Exchange (ETDEWEB)

Hannula, I.; Kurkela, E.

2013-04-15

With the objective of gaining a better understanding of the system design trade-offs and economics that pertain to biomass-to-liquids processes, 20 individual BTL plant designs were evaluated based on their technical and economic performance. The investigation was focused on gasification-based processes that enable the conversion of biomass to methanol, dimethyl ether, Fischer-Tropsch liquids or synthetic gasoline at a large (300 MWth of biomass) scale. The biomass conversion technology was based on pressurised steam/O2-blown fluidised-bed gasification, followed by hot-gas filtration and catalytic conversion of hydrocarbons and tars. This technology has seen extensive development and demonstration activities in Finland during the recent years and newly generated experimental data has also been used in our simulation models. Our study included conceptual design issues, process descriptions, mass and energy balances and production cost estimates. Several studies exist that discuss the overall efficiency and economics of biomass conversion to transportation liquids, but very few studies have presented a detailed comparison between various syntheses using consistent process designs and uniform cost database. In addition, no studies exist that examine and compare BTL plant designs using the same front-end configuration as described in this work. Our analysis shows that it is possible to produce sustainable low-carbon fuels from lignocellulosic biomass with first-law efficiency in the range of 49.6-66.7% depending on the end-product and process conditions. Production cost estimates were calculated assuming Nth plant economics and without public investment support, CO2 credits or tax assumptions. They are 58-65 euro/MWh for methanol, 58-66 euro/MWh for DME, 64-75 euro/MWh for Fischer-Tropsch liquids and 68-78 euro/MWh for synthetic gasoline. (orig.)

Availability of Dutch biomass for electricity and heat in 2020

International Nuclear Information System (INIS)

Koppejan, J.; Elbersen, W.; Meeusen, M.; Bindraban, P.

2009-11-01

Availability of biomass is an important factor in realizing the Dutch targets for renewable energy. This study maps the availability of Dutch biomass in the framework of alternative applications and sustainability requirements, today and in the future. The conclusion is drawn that there is approximately 13 to 16 million tons of dry biomass available for energy generation in the Netherlands in 2020. This is 30 to 40% of the amount of biomass that is annually used in the Netherlands, generating 53 to 94 PJ of final energy, avoiding 101 to 157 PJ of fossil energy. This availability of biomass and the energy that is generated from the biomass can increase further after 2020. In addition, biomass will also be imported, especially for combustion and co-firing in coal-fired power plants and for the production of transport fuels. [nl

Economic viability of the construction and operation of a biomass gasificator for poultry houses heating

Energy Technology Data Exchange (ETDEWEB)

Zanatta, Fabio Luiz; Silva, Jadir Nogueira da; Tinoco, Ilda de Fatima Ferreira; Martin, Samuel; Melo, Lucas D.; Bueno, Mateus [Universidade Federal de Vicosa (DEA/UFV), MG (Brazil). Dept. de Engenharia Agricola], E-mail: fzanatta@vicosa.ufv.br

2008-07-01

In all poultry farms, at least in the first days of life of the chicken, it is necessary to heat the environment to obtain a good development of the chicken and good economics results. However, this additional heat generation is sometimes neglected or not well executed, because of the costs that this practice could bring. This research has the objective of analyze the costs of construction and operation of a Biomass Gasificator for Poultry Houses Heating in comparison with a direct furnace system. The fuel used in both systems was firewood of eucalyptus. For so much, economic analyzes was make considering the costs of the gasification systems implementation in substitution of the traditional system used in the company (direct furnace system). For the viability the adopted method was the partial budget and the complementary investments were analyzed through the cash flow elaboration and of determination of indicator of economic feasibility. (author)

Testing, development and demonstration of large scale solar district heating systems

DEFF Research Database (Denmark)

Furbo, Simon; Fan, Jianhua; Perers, Bengt

2015-01-01

In 2013-2014 the project “Testing, development and demonstration of large scale solar district heating systems” was carried out within the Sino-Danish Renewable Energy Development Programme, the so called RED programme jointly developed by the Chinese and Danish governments. In the project Danish...... know how on solar heating plants and solar heating test technology have been transferred from Denmark to China, large solar heating systems have been promoted in China, test capabilities on solar collectors and large scale solar heating systems have been improved in China and Danish-Chinese cooperation...

Impact assessment of biomass-based district heating systems in densely populated communities. Part II: Would the replacement of fossil fuels improve ambient air quality and human health?

Science.gov (United States)

Petrov, Olga; Bi, Xiaotao; Lau, Anthony

2017-07-01

To determine if replacing fossil fuel combustion with biomass gasification would impact air quality, we evaluated the impact of a small-scale biomass gasification plant (BRDF) at a university campus over 5 scenarios. The overall incremental contribution of fine particles (PM2.5) is found to be at least one order of magnitude lower than the provincial air quality objectives. The maximum PM2.5 emission from the natural gas fueled power house (PH) could adversely add to the already high background concentration levels. Nitrogen dioxide (NO2) emissions from the BRDF with no engineered pollution controls for NOx in place exceeded the provincial objective in all seasons except during summer. The impact score, IS, was the highest for NO2 (677 Disability Adjusted Life Years, DALY) when biomass entirely replaced fossil fuels, and the highest for PM2.5 (64 DALY) and CO (3 DALY) if all energy was produced by natural gas at PH. Complete replacement of fossil fuels by one biomass plant can result in almost 28% higher health impacts (708 DALY) compared to 513 DALY when both the current BRDF and the PH are operational mostly due to uncontrolled NO2 emissions. Observations from this study inform academic community, city planners, policy makers and technology developers on the impacts of community district heating systems and possible mitigation strategies: a) community energy demand could be met either by splitting emissions into more than one source at different locations and different fuel types or by a single source with the least-impact-based location selection criteria with biomass as a fuel; b) advanced high-efficiency pollution control devices are essential to lower emissions for emission sources located in a densely populated community; c) a spatial and temporal impact assessment should be performed in developing bioenergy-based district heating systems, in which the capital and operational costs should be balanced with not only the benefit to greenhouse gas emission

Logistics, Costs, and GHG Impacts of Utility-Scale Co-Firing with 20% Biomass

Energy Technology Data Exchange (ETDEWEB)

Nichol, Corrie Ian [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2013-06-01

This study analyzes the possibility that biopower in the U.S. is a cost-competitive option to significantly reduce greenhouse gas emissions. In 2009, net greenhouse gas (GHG) emitted in the United States was equivalent to 5,618 million metric tons CO₂, up 5.6% from 1990 (EPA 2011). Coal-fired power generation accounted for 1,748 million metric tons of this total. Intuitively, life-cycle CO₂ emissions in the power sector could be reduced by substituting renewable biomass for coal. If just 20% of the coal combusted in 2009 had been replaced with biomass, CO₂ emissions would have been reduced by 350 million metric tons, or about 6% of net annual GHG emission. This would have required approximately 225 million tons of dry biomass. Such an ambitious fuel substitution would require development of a biomass feedstock production and supply system tantamount to coal. This material would need to meet stringent specifications to ensure reliable conveyance to boiler burners, efficient combustion, and no adverse impact on heat transfer surfaces and flue gas cleanup operations. Therefore, this report addresses the potential cost/benefit tradeoffs of co-firing 20% specification-qualified biomass (on an energy content basis) in large U.S. coal-fired power plants. The dependence and sensitivity of feedstock cost on source of material, location, supply distance, and demand pressure was established. Subsequently, the dependence of levelized cost of electricity (LCOE) on feedstock costs, power plant feed system retrofit, and impact on boiler performance was determined. Overall life-cycle assessment (LCA) of greenhouse gas emissions saving were next evaluated and compared to wind and solar energy to benchmark the leading alternatives for meeting renewable portfolio standards (or RPS).

Exergoeconomic analysis of small-scale biomass steam cogeneration

Energy Technology Data Exchange (ETDEWEB)

Rodriguez Sotomonte, Cesar Adolfo; Lora, Electo Eduardo Silva [Universidade Federal de Itajuba, MG (Brazil)], e-mails: c.rodriguez32@unifei.edu.br, electo@unifei.edu.br; Venturini, Osvaldo Jose; Escobar, Jose Carlos [Universidad Federal de Itajuba, MG (Brazil)], e-mail: osvaldo@unifei.edu.br

2010-07-01

The principal objective of this work is to develop a calculation process, based on the second law of thermodynamics, for evaluating the thermoeconomic potential of a small steam cogeneration plant using waste from pulp processing and/or sawmills as fuel. Four different configurations are presented and assessed. The exergetic efficiency of the cycles that use condensing turbines is found to be around 11%, which has almost 3 percent higher efficiency than cycles with back pressure turbines. The thermoeconomic equations used in this paper estimated the production costs varying the fuel price. The main results show that present cost of technologies in a small-scale steam cycle cogeneration do not justify the implementation of more efficient systems for biomass prices less than 100 R$/t. (author)

Pyrolysis as a technique for separating heavy metals from hyperaccumulators. Part III: pilot-scale pyrolysis of synthetic hyperaccumulator biomass

International Nuclear Information System (INIS)

Koppolu, Lakshmi; Prasad, Ramakrishna; Davis Clements, L.

2004-01-01

Synthetic hyperaccumulator biomass (SHB) feed impregnated with Ni, Zn or Cu was used to conduct six experiments in a pilot-scale, spouted bed gasifier. Two runs each using corn stover with no metal added (blank runs) were also conducted. The reactor was operated in an entrained mode in an oxygen free (N 2 ) environment at 873 K and 1 atm. The apparent gas residence time in the heated zone of the pilot-scale reactor was 1.4 s at 873 K. The material balance closure for the eight experiments on an N 2 -free basis varied between 79% and 92%. Nearly 99% of the metal recovered in the product stream was concentrated in the char formed by pyrolyzing the SHB in the reactor. The metal concentration in the char varied between 6.6% and 16.6%, depending on the type of metal and whether the char was collected in the cyclone or ashbox. The metal component was concentrated by 3.2-6 times in the char, compared to the feed

AUTOMATIC BIOMASS BOILER WITH AN EXTERNAL THERMOELECTRIC GENERATOR

Directory of Open Access Journals (Sweden)

Marian Brázdil

2014-02-01

Full Text Available This paper presents the design and test results of an external thermoelectric generator that utilizes the waste heat from a small-scale domestic biomass boiler with nominal rated heat output of 25 kW. The low-temperature Bi2Te3 generator based on thermoelectric modules has the potential to recover waste heat from gas combustion products as effective energy. The small-scale generator is constructed from independent segments. Measurements have shown that up to 11 W of electricity can be generated by one segment. Higher output power can be achieved by linking thermoelectric segments. The maximum output power is given by the dew point of the flue gas. The electrical energy that is generated can be used, e.g., for power supply or for charging batteries. In the near future, thermoelectric generators could completely eliminate the dependence an automated domestic boiler system on the power supply from the electricity grid, and could ensure comfortable operation in the event of an unexpected power grid failure.

Energy production from biomass

International Nuclear Information System (INIS)

Bestebroer, S.I.

1995-01-01

The aim of the task group 'Energy Production from Biomass', initiated by the Dutch Ministry of Economic Affairs, was to identify bottlenecks in the development of biomass for energy production. The bottlenecks were identified by means of a process analysis of clean biomass fuels to the production of electricity and/or heat. The subjects in the process analysis are the potential availability of biomass, logistics, processing techniques, energy use, environmental effects, economic impact, and stimulation measures. Three categories of biomass are distinguished: organic residual matter, imported biomass, and energy crops, cultivated in the Netherlands. With regard to the processing techniques attention is paid to co-firing of clean biomass in existing electric power plants (co-firing in a coal-fired power plant or co-firing of fuel gas from biomass in a coal-fired or natural gas-fired power plant), and the combustion or gasification of clean biomass in special stand-alone installations. 5 figs., 13 tabs., 28 refs

Lidar aboveground vegetation biomass estimates in shrublands: Prediction, uncertainties and application to coarser scales

Science.gov (United States)

Li, Aihua; Dhakal, Shital; Glenn, Nancy F.; Spaete, Luke P.; Shinneman, Douglas; Pilliod, David S.; Arkle, Robert; McIlroy, Susan

2017-01-01

Our study objectives were to model the aboveground biomass in a xeric shrub-steppe landscape with airborne light detection and ranging (Lidar) and explore the uncertainty associated with the models we created. We incorporated vegetation vertical structure information obtained from Lidar with ground-measured biomass data, allowing us to scale shrub biomass from small field sites (1 m subplots and 1 ha plots) to a larger landscape. A series of airborne Lidar-derived vegetation metrics were trained and linked with the field-measured biomass in Random Forests (RF) regression models. A Stepwise Multiple Regression (SMR) model was also explored as a comparison. Our results demonstrated that the important predictors from Lidar-derived metrics had a strong correlation with field-measured biomass in the RF regression models with a pseudo R2 of 0.76 and RMSE of 125 g/m2 for shrub biomass and a pseudo R2 of 0.74 and RMSE of 141 g/m2 for total biomass, and a weak correlation with field-measured herbaceous biomass. The SMR results were similar but slightly better than RF, explaining 77–79% of the variance, with RMSE ranging from 120 to 129 g/m2 for shrub and total biomass, respectively. We further explored the computational efficiency and relative accuracies of using point cloud and raster Lidar metrics at different resolutions (1 m to 1 ha). Metrics derived from the Lidar point cloud processing led to improved biomass estimates at nearly all resolutions in comparison to raster-derived Lidar metrics. Only at 1 m were the results from the point cloud and raster products nearly equivalent. The best Lidar prediction models of biomass at the plot-level (1 ha) were achieved when Lidar metrics were derived from an average of fine resolution (1 m) metrics to minimize boundary effects and to smooth variability. Overall, both RF and SMR methods explained more than 74% of the variance in biomass, with the most important Lidar variables being associated with vegetation structure

Overview of biomass conversion technologies

International Nuclear Information System (INIS)

Noor, S.; Latif, A.; Jan, M.

2011-01-01

A large part of the biomass is used for non-commercial purposes and mostly for cooking and heating, but the use is not sustainable, because it destroys soil-nutrients, causes indoor and outdoor pollution, adds to greenhouse gases, and results in health problems. Commercial use of biomass includes household fuelwood in industrialized countries and bio-char (charcoal) and firewood in urban and industrial areas in developing countries. The most efficient way of biomass utilization is through gasification, in which the gas produced by biomass gasification can either be used to generate power in an ordinary steam-cycle or be converted into motor fuel. In the latter case, there are two alternatives, namely, the synthesis of methanol and methanol-based motor fuels, or Fischer-Tropsch hydrocarbon synthesis. This paper deals with the technological overview of the state-of-the-art key biomass-conversion technologies that can play an important role in the future. The conversion routes for production of Heat, power and transportation fuel have been summarized in this paper, viz. combustion, gasification, pyrolysis, digestion, fermentation and extraction. (author)

Assessment of Biomass Resources in Afghanistan

Energy Technology Data Exchange (ETDEWEB)

Milbrandt, A.; Overend, R.

2011-01-01

Afghanistan is facing many challenges on its path of reconstruction and development. Among all its pressing needs, the country would benefit from the development and implementation of an energy strategy. In addition to conventional energy sources, the Afghan government is considering alternative options such as energy derived from renewable resources (wind, solar, biomass, geothermal). Biomass energy is derived from a variety of sources -- plant-based material and residues -- and can be used in various conversion processes to yield power, heat, steam, and fuel. This study provides policymakers and industry developers with information on the biomass resource potential in Afghanistan for power/heat generation and transportation fuels production. To achieve this goal, the study estimates the current biomass resources and evaluates the potential resources that could be used for energy purposes.

Effect of biomass concentration on the productivity of Tetraselmis suecica in a pilot-scale tubular photobioreactor using natural sunlight

NARCIS (Netherlands)

Michels, M.H.A.; Slegers, P.M.; Vermue, M.H.; Wijffels, R.H.

2014-01-01

The effect of biomass concentration on the net volumetric productivity, yield on light and nightly biomass loss rate of Tetraselmis suecica was studied using a pilot-scale tubular photobioreactor (PBR) under outdoor light conditions. The net average productivity and yield on light of Tetraselmis

Computational Model of a Biomass Driven Absorption Refrigeration System

Directory of Open Access Journals (Sweden)

Munyeowaji Mbikan

2017-02-01

Full Text Available The impact of vapour compression refrigeration is the main push for scientists to find an alternative sustainable technology. Vapour absorption is an ideal technology which makes use of waste heat or renewable heat, such as biomass, to drive absorption chillers from medium to large applications. In this paper, the aim was to investigate the feasibility of a biomass driven aqua-ammonia absorption system. An estimation of the solid biomass fuel quantity required to provide heat for the operation of a vapour absorption refrigeration cycle (VARC is presented; the quantity of biomass required depends on the fuel density and the efficiency of the combustion and heat transfer systems. A single-stage aqua-ammonia refrigeration system analysis routine was developed to evaluate the system performance and ascertain the rate of energy transfer required to operate the system, and hence, the biomass quantity needed. In conclusion, this study demonstrated the results of the performance of a computational model of an aqua-ammonia system under a range of parameters. The model showed good agreement with published experimental data.

Primary energy savings using heat storage for biomass heating systems

Directory of Open Access Journals (Sweden)

Mitrović Dejan M.

2012-01-01

Full Text Available District heating is an efficient way to provide heat to residential, tertiary and industrial users. The heat storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the heat storage unit makes it possible to heat even when the boiler is not working, thus increasing the heating efficiency. In order to save primary energy (fuel, the boiler operates on nominal load every time it is in operation (for the purpose of this research. The aim of this paper is to analyze the water temperature variation in the heat storage, depending on the heat load and the heat storage volume. Heat load is calculated for three reference days, with average daily temperatures from -5 to 5°C. The primary energy savings are also calculated for those days in the case of using heat storage in district heating.[Projekat Ministarstva nauke Republike Srbije, br. TR 33051: The concept of sustainable energy supply of settlements with energy efficient buildings

Modelling of biomass pyrolysis

International Nuclear Information System (INIS)

Kazakova, Nadezhda; Petkov, Venko; Mihailov, Emil

2015-01-01

Pyrolysis is an essential preliminary step in a gasifier. The first step in modelling the pyrolysis process of biomass is creating a model for the chemical processes taking place. This model should describe the used fuel, the reactions taking place and the products created in the process. The numerous different polymers present in the organic fraction of the fuel are generally divided in three main groups. So, the multistep kinetic model of biomass pyrolysis is based on conventional multistep devolatilization models of the three main biomass components - cellulose, hemicelluloses, and lignin. Numerical simulations have been conducted in order to estimate the influence of the heating rate and the temperature of pyrolysis on the content of the virgin biomass, active biomass, liquid, solid and gaseous phases at any moment. Keywords: kinetic models, pyrolysis, biomass pyrolysis.

Far-infrared irradiation drying behavior of typical biomass briquettes

International Nuclear Information System (INIS)

Chen, N.N.; Chen, M.Q.; Fu, B.A.; Song, J.J.

2017-01-01

Infrared radiation drying behaviors of four typical biomass briquettes (populus tomentosa leaves, cotton stalk, spent coffee grounds and eucalyptus bark) were investigated based on a lab-scale setup. The effect of radiation source temperatures (100–200 °C) on the far-infrared drying kinetics and heat transfer of the samples was addressed. As the temperature went up from 100 °C to 200 °C, the time required for the four biomass briquettes drying decreased by about 59–66%, and the average values of temperature for the four biomass briquettes increased by about 33–39 °C, while the average radiation heat transfer fluxes increased by about 3.3 times (3.7 times only for the leaves). The specific energy consumptions were 0.622–0.849 kW h kg"−"1. The Modified Midilli model had the better representing for the moisture ratio change of the briquettes. The values of the activation energy for the briquettes in the first falling rate stage were between 20.35 and 24.83 kJ mol"−"1, while those in the second falling rate stage were between 17.89 and 21.93 kJ mol"−"1. The activation energy for the eucalyptus bark briquette in two falling rate stages was the least one, and that for the cotton stalk briquette was less than that for the rest two briquettes. - Highlights: • Far infrared drying behaviors of four typical biomass briquettes were addressed. • The effect of radiation source temperatures on IR drying kinetics was stated. • Radiation heat transfer flux between the sample and heater was evaluated. • Midilli model had the better representing for the drying process of the samples.

Thermal power generation projects ``Large Scale Solar Heating``; EU-Thermie-Projekte ``Large Scale Solar Heating``

Energy Technology Data Exchange (ETDEWEB)

Kuebler, R.; Fisch, M.N. [Steinbeis-Transferzentrum Energie-, Gebaeude- und Solartechnik, Stuttgart (Germany)

1998-12-31

The aim of this project is the preparation of the ``Large-Scale Solar Heating`` programme for an Europe-wide development of subject technology. The following demonstration programme was judged well by the experts but was not immediately (1996) accepted for financial subsidies. In November 1997 the EU-commission provided 1,5 million ECU which allowed the realisation of an updated project proposal. By mid 1997 a small project was approved, that had been requested under the lead of Chalmes Industriteteknik (CIT) in Sweden and is mainly carried out for the transfer of technology. (orig.) [Deutsch] Ziel dieses Vorhabens ist die Vorbereitung eines Schwerpunktprogramms `Large Scale Solar Heating`, mit dem die Technologie europaweit weiterentwickelt werden sollte. Das daraus entwickelte Demonstrationsprogramm wurde von den Gutachtern positiv bewertet, konnte jedoch nicht auf Anhieb (1996) in die Foerderung aufgenommen werden. Im November 1997 wurden von der EU-Kommission dann kurzfristig noch 1,5 Mio ECU an Foerderung bewilligt, mit denen ein aktualisierter Projektvorschlag realisiert werden kann. Bereits Mitte 1997 wurde ein kleineres Vorhaben bewilligt, das unter Federfuehrung von Chalmers Industriteknik (CIT) in Schweden beantragt worden war und das vor allem dem Technologietransfer dient. (orig.)

Biomass route shows lower cost

Energy Technology Data Exchange (ETDEWEB)

Taffe, P

1980-11-21

There has been much discussion concerning the economics of using biomass for the production of substitute fuels and it has been argued that the net energy gain could be small or even negative. The development of the ATPAL process is described and it is claimed that only one quarter of the energy equivalent contained in the alcohol will be consumed in the total process. Both the pilot plant and a commercial scale plant with some modifications are described. The most significant advantage claimed for the ATPAL process is in its low process energy savings resulting from mechanical vapour recompression, recycling the heat and production of a low volume of effluent.

Life cycle assessment of biomass-to-energy systems in Ireland modelled with biomass supply chain optimisation based on greenhouse gas emission reduction

International Nuclear Information System (INIS)

Murphy, Fionnuala; Sosa, Amanda; McDonnell, Kevin; Devlin, Ger

2016-01-01

The energy sector is the major contributor to GHG (greenhouse gas emissions) in Ireland. Under EU Renewable energy targets, Ireland must achieve contributions of 40%, 12% and 10% from renewables to electricity, heat and transport respectively by 2020, in addition to a 20% reduction in GHG emissions. Life cycle assessment methodology was used to carry out a comprehensive, holistic evaluation of biomass-to-energy systems in 2020 based on indigenous biomass supply chains optimised to reduce production and transportation GHG emissions. Impact categories assessed include; global warming, acidification, eutrophication potentials, and energy demand. Two biomass energy conversion technologies are considered; co-firing with peat, and biomass CHP (combined heat and power) systems. Biomass is allocated to each plant according to a supply optimisation model which ensures minimal GHG emissions. The study shows that while CHP systems produce lower environmental impacts than co-firing systems in isolation, determining overall environmental impacts requires analysis of the reference energy systems which are displaced. In addition, if the aims of these systems are to increase renewable energy penetration in line with the renewable electricity and renewable heat targets, the optimal scenario may not be the one which achieves the greatest environmental impact reductions. - Highlights: • Life cycle assessment of biomass co-firing and CHP systems in Ireland is carried out. • GWP, acidification and eutrophication potentials, and energy demand are assessed. • Biomass supply is optimised based on minimising GHG emissions. • CHP systems cause lower environmental impacts than biomass co-firing with peat. • Displacing peat achieves higher GHG emission reductions than replacing fossil heat.

Energy of forest biomass in Croatia

International Nuclear Information System (INIS)

Cupin, N.; Krivak, B.; Dundovic, J.

2005-01-01

Forest biomass is organic substance raised in forest ecosystem, consisting of trees and bushes which are used for mechanical processing and thermal use. Croatia, with 44 percent of surface under forests, has the renewable energy potential in forest biomass that could cover as much as about 50 percent of the current heating consumption. The existence of an appropriate heating consume and district heating are a prerequisite for exploitation of the mentioned potential. At the same time, heating consumption enables the utilization of cogeneration plants and the paper gives examples of such possibilities in industry, community and special facilities (sport centres, hotels, hospitals etc.). Among them, the so called 'Croatian energy absurdum' is mentioned. The paper underlines the feasibility of exploitation of forest biomass at the national level and suggests that, in order to promote and accelerate the development of cogeneration plants, the HED expert group should be established. The task of the expert group would be to draft proposal for appropriate measures in this regard and submit it to the Government for consideration.(author)

Natural gas–biomass dual fuelled microturbines: Comparison of operating strategies in the Italian residential sector

International Nuclear Information System (INIS)

Pantaleo, Antonio M.; Camporeale, Sergio; Shah, Nilay

2014-01-01

This paper compares different operating strategies for small scale (100 kWe) combined heat and power (CHP) plants fired by natural gas and solid biomass to serve a residential energy demand. The focus is on a dual fuel micro gas turbine (MGT) cycle. Various biomass/natural gas energy input ratios are modelled, in order to assess the trade-offs between: (i) lower energy conversion efficiency and higher investment cost when increasing the biomass input rate; (ii) higher primary energy savings and revenues from feed-in tariff available for biomass electricity fed into the grid. The strategies of baseload (BL), heat driven (HD) and electricity driven (ED) plant operation are compared, for an aggregate of residential end-users in cold, average and mild climate conditions. On the basis of the results from thermodynamic assessment and simulation at partial load operation, CAPEX and OPEX estimates, and Italian energy policy scenario (incentives available for biomass electricity, on-site and high efficiency CHP), the maximum global energy efficiency, primary energy savings and investment profitability is found, as a function of biomass/natural gas ratio, plant operating strategy and energy demand typology. The thermal and electric conversion efficiency ranged respectively between 46 and 38% and 30 and 19% for the natural gas and biomass fired case studies. The IRR of the investment was highly influenced by the load/CHP thermal power ratio and by the operation mode. The availability of high heat demand levels was also a key factor, to avoid wasted cogenerated heat and maximize CHP sales revenues. BL operation presented the highest profitability because of the higher revenues from electricity sales. Climate area was another important factor, mainly in case of low load/CHP ratios. Moreover, at low load/CHP power ratio and for the BL operation mode, the dual fuel option presented the highest profitability. This is due to the lower cost of biomass fuel in comparison to natural

Lab-scale experiment of a closed thermochemical heat storage system including honeycomb heat exchanger

International Nuclear Information System (INIS)

Fopah-Lele, Armand; Rohde, Christian; Neumann, Karsten; Tietjen, Theo; Rönnebeck, Thomas; N'Tsoukpoe, Kokouvi Edem; Osterland, Thomas; Opel, Oliver

2016-01-01

A lab-scale thermochemical heat storage reactor was developed in the European project “thermal battery” to obtain information on the characteristics of a closed heat storage system, based on thermochemical reactions. The present type of storage is capable of re-using waste heat from cogeneration system to produce useful heat for space heating. The storage material used was SrBr 2 ·6H 2 O. Due to agglomeration or gel-like problems, a structural element was introduced to enhance vapour and heat transfer. Honeycomb heat exchanger was designed and tested. 13 dehydration-hydration cycles were studied under low-temperature conditions (material temperatures < 100 °C) for storage. Discharging was realized at water vapour pressure of about 42 mbar. Temperature evolution inside the reactor at different times and positions, chemical conversion, thermal power and overall efficiency were analysed for the selected cycles. Experimental system thermal capacity and efficiency of 65 kWh and 0.77 are respectively obtained with about 1 kg of SrBr 2 ·6H 2 O. Heat transfer fluid recovers heat at a short span of about 43 °C with an average of 22 °C during about 4 h, acceptable temperature for the human comfort (20 °C on day and 16 °C at night). System performances were obtained for a salt bed energy density of 213 kWh·m 3 . The overall heat transfer coefficient of the honeycomb heat exchanger has an average value of 147 W m −2  K −1 . Though promising results have been obtained, ameliorations need to be made, in order to make the closed thermochemical heat storage system competitive for space heating. - Highlights: • Lab-scale thermochemical heat storage is designed, constructed and tested. • The use of honeycomb heat exchanger as a heat and vapour process enhancement. • Closed system (1 kg SrBr 2 ·6H 2 O) able to give back 3/4 of initial thermal waste energy. • System storage capacity and thermal efficiency are respectively 65 kWh and 0.77. �

Penetrating the markets: biomass and commercial distribution

International Nuclear Information System (INIS)

Schmidl, J.

1999-01-01

Although biomass accounts for a significant proportion of renewable energy in Europe, its market penetration could be increased if certain barriers can be surmounted. Some of those barriers are identified and suggestions made as to how they may be overcome through improved 'distribution' in various sectors. To integrate biomass into the electricity distribution system, the commercial distribution of liquid biofuels, and in the commercial distribution of biomass in the heat sector, certain rewards and penalties could be introduced and these are discussed. The low temperature heat market is seen as very important for the further development of bioenergy in Europe. (UK)

Spatial and topographic trends in forest expansion and biomass change, from regional to local scales.

Science.gov (United States)

Buma, Brian; Barrett, Tara M

2015-09-01

Natural forest growth and expansion are important carbon sequestration processes globally. Climate change is likely to increase forest growth in some regions via CO2 fertilization, increased temperatures, and altered precipitation; however, altered disturbance regimes and climate stress (e.g. drought) will act to reduce carbon stocks in forests as well. Observations of asynchrony in forest change is useful in determining current trends in forest carbon stocks, both in terms of forest density (e.g. Mg ha(-1) ) and spatially (extent and location). Monitoring change in natural (unmanaged) areas is particularly useful, as while afforestation and recovery from historic land use are currently large carbon sinks, the long-term viability of those sinks depends on climate change and disturbance dynamics at their particular location. We utilize a large, unmanaged biome (>135 000 km(2) ) which spans a broad latitudinal gradient to explore how variation in location affects forest density and spatial patterning: the forests of the North American temperate rainforests in Alaska, which store >2.8 Pg C in biomass and soil, equivalent to >8% of the C in contiguous US forests. We demonstrate that the regional biome is shifting; gains exceed losses and are located in different spatio-topographic contexts. Forest gains are concentrated on northerly aspects, lower elevations, and higher latitudes, especially in sheltered areas, whereas loss is skewed toward southerly aspects and lower latitudes. Repeat plot-scale biomass data (n = 759) indicate that within-forest biomass gains outpace losses (live trees >12.7 cm diameter, 986 Gg yr(-1) ) on gentler slopes and in higher latitudes. This work demonstrates that while temperate rainforest dynamics occur at fine spatial scales (biomass accumulation suggest the potential for relatively rapid biome shifts and biomass changes. © 2015 John Wiley & Sons Ltd.

An overview of CFD modelling of small-scale fixed-bed biomass pellet boilers with preliminary results from a simplified approach

International Nuclear Information System (INIS)

Chaney, Joel; Liu Hao; Li Jinxing

2012-01-01

Highlights: ► Overview of the overall approach of modelling fixed-bed biomass boilers in CFD. ► Bed sub-models of moisture evaporation, devolatisation and char combustion reviewed. ► A method of embedding a combustion model in discrete fuel zones within the CFD is suggested. ► Includes sample of preliminary results for a 50 kW pellet boiler. ► Clear physical trends predicted. - Abstract: The increasing global energy demand and mounting pressures for CO 2 mitigation call for increased efficient utilization of biomass, particularly for heating domestic and commercial buildings. The authors of the present paper are investigating the optimization of the combustion performance and NO x emissions of a 50 kW biomass pellet boiler fabricated by a UK manufacturer. The boiler has a number of adjustable parameters including the ratio of air flow split between the primary and secondary supplies, the orientation, height, direction and number of the secondary inlets. The optimization of these parameters provides opportunities to improve both the combustion efficiency and NO x emissions. When used carefully in conjunction with experiments, Computational Fluid Dynamics (CFD) modelling is a useful tool for rapidly and at minimum cost examining the combustion performance and emissions from a boiler with multiple variable parameters. However, modelling combustion and emissions of a small-scale biomass pellet boiler is not trivial and appropriate fixed-bed models that can be coupled with the CFD code are required. This paper reviews previous approaches specifically relevant to simulating fixed-bed biomass boilers. In the first part it considers approaches to modelling the heterogeneous solid phase and coupling this with the gas phase. The essential components of the sub-models are then overviewed. Importantly, for the optimization process a model is required that has a good balance between accuracy in predicting physical trends, with low computational run time. Finally, a

Hot Gas Conditioning: Recent Progress with Larger-Scale Biomass Gasification Systems; Update and Summary of Recent Progress

Energy Technology Data Exchange (ETDEWEB)

Stevens, D. J.

2001-09-01

As a result of environmental and policy considerations, there is increasing interest in using renewable biomass resources as feedstock for power, fuels, and chemicals and hydrogen. Biomass gasification is seen as an important technology component for expanding the use of biomass. Advanced biomass gasification systems provide clean products that can be used as fuel or synthesis gases in a variety of environmentally friendly processes. Advanced end-use technologies such as gas turbines or synthesis gas systems require high quality gases with narrowly defined specifications. Other systems such as boilers may also have fuel quality requirements, but they will be substantially less demanding. The gas product from biomass gasifiers contains quantities of particulates, tars, and other constituents that may exceed these specified limits. As a result, gas cleaning and conditioning will be required in most systems. Over the past decade, significant research and development activities have been conducted on the topic of gas cleanup and conditioning. This report provides an update of efforts related to large-scale biomass gasification systems and summarizes recent progress. Remaining research and development issues are also summarized.

Economic and CO2 mitigation impacts of promoting biomass heating systems: An input-output study for Vorarlberg, Austria

International Nuclear Information System (INIS)

Madlener, Reinhard; Koller, Martin

2007-01-01

This paper reports on an empirical investigation about the economic and CO 2 mitigation impacts of bioenergy promotion in the Austrian federal province of Vorarlberg. We study domestic value-added, employment, and fiscal effects by means of a static input-output analysis. The bioenergy systems analysed comprise biomass district heating, pellet heating, and automated wood chip heating systems, as well as logwood stoves and boilers, ceramic stoves, and buffer storage systems. The results indicate that gross economic effects are significant, regarding both investment and operation of the systems, and that the negative economic effects caused by the displacement of conventional decentralised heating systems might be in the order of 20-40%. Finally, CO 2 mitigation effects are substantial, contributing already in 2004 around 35% of the 2010 CO 2 mitigation target of the Land Vorarlberg for all renewable energy sources

Technology Roadmaps: Bioenergy for Heat and Power

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

The Technology Roadmap Bioenergy for Heat and Power highlights the importance of bioenergy in providing heat in the buildings sector and in industry, and shows what contribution it could make to meeting steadlily growing world electricity demand. The critical role of sustainability as well as the importance of international trade in meeting the projected demand for bioenergy, are highlighted in the roadmap, as well as the need for large-scale biomass plants in providing The roadmap identifies key actions by different stakeholders in the bioenergy sector, and sets out milestones for technology development in order to achieve a doubling of global bioenergy supply by 2050. It addresses the need for further R&D efforts, highlights measures to ensure sustainability of biomass production, and underlines the need for international collaboration to enhance the production and use of sustainable, modern bioenergy in different world regions.

Technology Roadmaps: Bioenergy for Heat and Power

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-08-01

The Technology Roadmap Bioenergy for Heat and Power highlights the importance of bioenergy in providing heat in the buildings sector and in industry, and shows what contribution it could make to meeting steadlily growing world electricity demand. The critical role of sustainability as well as the importance of international trade in meeting the projected demand for bioenergy, are highlighted in the roadmap, as well as the need for large-scale biomass plants in providing The roadmap identifies key actions by different stakeholders in the bioenergy sector, and sets out milestones for technology development in order to achieve a doubling of global bioenergy supply by 2050. It addresses the need for further R&D efforts, highlights measures to ensure sustainability of biomass production, and underlines the need for international collaboration to enhance the production and use of sustainable, modern bioenergy in different world regions.

The French market of biomass. An analysis of barriers and levers of development of the wood-energy sector, main biomass resource

International Nuclear Information System (INIS)

2011-06-01

This article presents the content of a market study which aimed at assessing the weight of wood-energy in the French energy mix when it represents 97 per cent of biomass consumed under the form of heat, at giving an overview of markets within which this energy is now valorised (housing heating, heat and cogeneration), at analysing the business model of biomass projects, at assessing mechanisms aimed at supporting this sector, and at assessing the potential of the French market as far as wood-energy is concerned. The report presents the operation principles and applications of biomass, analyses the share of wood-energy in the French energy mix and the objectives defined by the Grenelle de l'Environnement, presents the French forests as an abundant resource, comments wood-based heating of housing as an evolving market, presents and analyses the market of industrial and collective heat, and discusses the perspective of a multiplication by 4 by 2020 of cogeneration installed capacities

Domestic heating - the biomass challenge

International Nuclear Information System (INIS)

Rakos, C.

1999-01-01

This article highlights currently available efficient, low emission technical concepts for the combustion of wood, log-burning boilers, woodchip boilers, and the use of wood pellets. The economics of domestic heating with wood, the higher costs incurred with modern efficient wood burners as compared with fuelwood costs, and the proposed European Commission's campaign to implement more wood heated dwellings are discussed, and the transition from traditional to modern wood heating, and options for stimulating growth in renewable energy are considered

Heat and mass transfer intensification and shape optimization a multi-scale approach

CERN Document Server

2013-01-01

Is the heat and mass transfer intensification defined as a new paradigm of process engineering, or is it just a common and old idea, renamed and given the current taste? Where might intensification occur? How to achieve intensification? How the shape optimization of thermal and fluidic devices leads to intensified heat and mass transfers? To answer these questions, Heat & Mass Transfer Intensification and Shape Optimization: A Multi-scale Approach clarifies  the definition of the intensification by highlighting the potential role of the multi-scale structures, the specific interfacial area, the distribution of driving force, the modes of energy supply and the temporal aspects of processes.   A reflection on the methods of process intensification or heat and mass transfer enhancement in multi-scale structures is provided, including porous media, heat exchangers, fluid distributors, mixers and reactors. A multi-scale approach to achieve intensification and shape optimization is developed and clearly expla...

The biomass energy market in Finland

International Nuclear Information System (INIS)

2002-01-01

In 2001, it was estimated that the Finnish biomass market was in excess of 235 million dollars. The development of renewable energy, with special emphasis on biomass, was supported by the development of an energy strategy by the government of Finland. The installed capacity of biomass in Finland in 2002 was 1400 megawatt electrical (MWe). Extensive use of combined heat and power (CHP) is made in Finland, and district heating (DH) systems using biomass are gaining in popularity. Wood-based biomass technologies, retrofits to fluidized bed combustion, and wood procurement technologies were identified as the best opportunities for Canadian companies interested in operating in Finland. A country with high standards, Finland seems to look favorably on new innovative solutions. Joint ventures with Finnish companies might be an excellent way for Canadian companies to gain a foothold in Finland and expand into the European Union, the Nordic countries, the Baltic, Russia and the Central and Eastern European markets. It was further noted that Finland is one of the leading exporters of biomass technology in the world. The document provided quick facts, examined opportunities, and looked at key players. 19 refs., 4 tabs

Electrodialytic removal of cadmium from biomass combustion fly ash in larger scale

DEFF Research Database (Denmark)

Pedersen, Anne Juul; Ottosen, Lisbeth M.; Simonsen, Peter

2005-01-01

Due to a high concentration of the toxic heavy metal cadmium (Cd), biomass combustion fly ash often fails to meet the Danish legislative requirements for recycling on agricultural fields. It has previously been shown that it is possible to reduce the concentration of Cd in different bio ashes...... significantly by using electrodialytic remediation, an electrochemically assisted extraction method. In this work the potential of the method was demonstrated in larger scale. Three different experimental set-ups were used, ranging from bench-scale (25 L ash suspension) to pilot scale (0.3 - 3 m3......). The experimental ash was a straw combustion fly ash suspended in water. Within 4 days of remediation, Cd concentrations below the limiting concentration of 5.0 mg Cd/kg DM for straw ash were reached. On the basis of these results, the energy costs for remediation of ash in industrial scale have been estimated...

Shorea robusta: A sustainable biomass feedstock

Directory of Open Access Journals (Sweden)

Vishal Kumar Singh

2016-09-01

Full Text Available The biomass feedstock needs to be available in a manner that is sustainable as well as renewable. However, obtaining reliable and cost effective supplies of biomass feedstock produced in a sustainable manner can prove to be difficult. Traditional biomass, mainly in the form of fallen leaves, fuel wood or dried dung, has long been the renewable and sustainable energy source for cooking and heating. Present study accounts for the biomass of fallen leaves of Shorea robusta, also known as sal, sakhua or shala tree, in the campus of BIT Mesra (Ranchi. These leaves are being gathered and burnt rather than being sold commercially. They contain water to varying degrees which affects their energy content. Hence, measurement of moisture content is critical for its biomass assessment. The leaves were collected, weighed, oven dried at 100oC until constant weight, then dry sample was reweighed to calculate the moisture content that has been driven off. By subtraction of moisture content from the initial weight of leaves, biomass was calculated. Using Differential Scanning Calorimeter (DSC the heat content of the leaves was calculated and the elemental analysis of leaf was done by CHNSO elemental analyser. Further, total biomass and carbon content of Sal tree was calculated using allometric equations so as to make a comparison to the biomass stored in dried fallen leaves

Clean and efficient application of biomass for production of power and heat - Phase 3 in a long-term strategic research project

Energy Technology Data Exchange (ETDEWEB)

Frandsen, F.J.; Jensen, A.D.; Jensen, P.A.; Johnsson, J.E.; Dam-Johansen, K.

2002-06-01

This project contains activities on: Rheology of ashes from co-firing of coal and biomass; Investigation of ash and deposit formation in full-scale utility boilers; and Selective catalytic reduction: Deactivation under biomass combustion. A fly ash and deposit investigation was carried out as part of the SK Power Company test programme on co-firing of biomasses in a grate-fired boiler. The alternative biomasses (wood chips, olive stones and shea nuts) contain more K, S, and Cl, than wheat straw, and higher fly ash mass loading (mass of fly ash/volume of flue gas) was observed when co-firing alternative biomasses with wheat straw. Anyhow, no significant change in deposit structure when co-firing alkali-rich biomass was observed: KCl is glues residual ash particles together, independent of the feedstock mixture. Thus it can be concluded that co-firing of the actual biomasses in boilers designed for straw-firing, at the present shares is not problematic, from an ash formation and/or deposit build-up point-of-view. Anyhow the increase in ash mass loading in the flue gas, may cause increased build-up of particulate deposits in the convective pass of the boiler. Mature deposit samples from the Masnedoe and Ensted straw-fired boilers were investigated by SEM and EDX. Each deposit sample was classified into an inner, an intermediate, and an outer main layer. The outermost deposit layers at Masnedoe and Ensted looked chemically quite similar, even though they were of different colours. The intermediate layer at Ensted contained many Si- and Ca-rich particles glued together by melted KCI, while the intermediate deposit layers at Masnedoe were different. Since the straw fuels probably are similar, the differences observed in the deposit chemistry must be induced by the higher temperature of the Masnedoe deposit. An experimental method has been set up for viscosity determinations on ashes from co-firing with wheat straw. The method contains a pre-treatment of the ashes, where

Decentralised power generation using solid biomass - Know-how on combined heat and power generation for investors; Dezentrale Stromerzeugung mit Feststoffbiomasse

Energy Technology Data Exchange (ETDEWEB)

Schmid, M.; Gaegauf, Ch.; Sattler, M.

2007-01-15

This comprehensive report made by the Centre of Appropriate Technology and Social Ecology in Langenbruck, Switzerland presents a summary of know-how for investors on combined heat and power generation using solid biomass in installations with an electrical rating of up to one megawatt. Topics covered include a review of the reasons for using biomass to generate electricity - with the results of an analysis of potential in Switzerland and the European Union - and of economic assessment methods for the choice of technology and manufacturers. A SWOT (strengths, weaknesses, opportunities and threats) analysis of technologies is presented and existing biomass-fired installations in Switzerland are listed. A comparison with centrally-refined combustibles is presented and examples of cost and profitability calculations are given. Finally technological background information is presented, including information on 'forgotten' technologies.

District heating as the infrastructure for competition among fuels and technologies

DEFF Research Database (Denmark)

Grohnheit, Poul Erik; Mortensen, Bent Ole Gram

2016-01-01

for increased energy efficiency. Additional technologies suitable for small-scale networks are heat pumps, solar panels and local biomass in the form of straw or biogas. For large-scale urban networks, incineration of urban waste and geothermal heat are key technologies. With heat storages district heating...... infrastructure can contribute significantly to balancing the intermittency of wind power. This paper is an update of the authors' article published in Energy Policy in 2003 focusing on the European directives focusing on competition in the electricity and gas network industries and promotion of renewables...... and cogeneration but limited support for the development and expansion of the district heating infrastructure. It was partly based on a contribution to the Shared Analysis Project for the European Commission Directorate-General for Energy, concerning the penetration of combined heat and power (CHP), energy saving...

Modeling aboveground tree woody biomass using national-scale allometric methods and airborne lidar

Science.gov (United States)

Chen, Qi

2015-08-01

Estimating tree aboveground biomass (AGB) and carbon (C) stocks using remote sensing is a critical component for understanding the global C cycle and mitigating climate change. However, the importance of allometry for remote sensing of AGB has not been recognized until recently. The overarching goals of this study are to understand the differences and relationships among three national-scale allometric methods (CRM, Jenkins, and the regional models) of the Forest Inventory and Analysis (FIA) program in the U.S. and to examine the impacts of using alternative allometry on the fitting statistics of remote sensing-based woody AGB models. Airborne lidar data from three study sites in the Pacific Northwest, USA were used to predict woody AGB estimated from the different allometric methods. It was found that the CRM and Jenkins estimates of woody AGB are related via the CRM adjustment factor. In terms of lidar-biomass modeling, CRM had the smallest model errors, while the Jenkins method had the largest ones and the regional method was between. The best model fitting from CRM is attributed to its inclusion of tree height in calculating merchantable stem volume and the strong dependence of non-merchantable stem biomass on merchantable stem biomass. This study also argues that it is important to characterize the allometric model errors for gaining a complete understanding of the remotely-sensed AGB prediction errors.

Numerical simulation of vortex pyrolysis reactors for condensable tar production from biomass

Energy Technology Data Exchange (ETDEWEB)

Miller, R.S.; Bellan, J. [California Inst. of Tech., Pasadena, CA (United States). Jet Propulsion Lab.

1998-08-01

A numerical study is performed in order to evaluate the performance and optimal operating conditions of vortex pyrolysis reactors used for condensable tar production from biomass. A detailed mathematical model of porous biomass particle pyrolysis is coupled with a compressible Reynolds stress transport model for the turbulent reactor swirling flow. An initial evaluation of particle dimensionality effects is made through comparisons of single- (1D) and multi-dimensional particle simulations and reveals that the 1D particle model results in conservative estimates for total pyrolysis conversion times and tar collection. The observed deviations are due predominantly to geometry effects while directional effects from thermal conductivity and permeability variations are relatively small. Rapid ablative particle heating rates are attributed to a mechanical fragmentation of the biomass particles that is modeled using a critical porosity for matrix breakup. Optimal thermal conditions for tar production are observed for 900 K. Effects of biomass identity, particle size distribution, and reactor geometry and scale are discussed.

A review on torrefaction of biomass

Energy Technology Data Exchange (ETDEWEB)

Tapasvi, Dhruv; Tran, Khanh-Quang

2010-07-01

Full text: Torrefaction is a mild-pyrolysis (200-300 deg.C.) process which can be employed as pre-treatment to improve fuel properties of plant biomass materials. The treatment results in not only improved energy density, but also enhanced grindability and better storage characteristics for biomass fuels. Because of these advantages and the high level of viability, the technique has attracted increasing interests during the last decades. Several studies on torrefaction of biomass for heat and power applications have been documented. Substantial amounts of data on the technique are available in the literature, which need to be reviewed and analyzed for further actions in the area. This is the primary objective of the present study. This review is consisted of three parts, of which the first focuses on the mechanism of biomass torrefaction for heat and power applications, and the process as a whole. It is then followed by a critical review on experimental methods in laboratory, and effects of operating parameters on fuel properties of torrefied biomass. Finally, opportunities and challenges for the process are discussed. (Author)

Scaling the heterogeneously heated convective boundary layer

Science.gov (United States)

Van Heerwaarden, C.; Mellado, J.; De Lozar, A.

2013-12-01

We have studied the heterogeneously heated convective boundary layer (CBL) by means of large-eddy simulations (LES) and direct numerical simulations (DNS). What makes our study different from previous studies on this subject are our very long simulations in which the system travels through multiple states and that from there we have derived scaling laws. In our setup, a stratified atmosphere is heated from below by square patches with a high surface buoyancy flux, surrounded by regions with no or little flux. By letting a boundary layer grow in time we let the system evolve from the so-called meso-scale to the micro-scale regime. In the former the heterogeneity is large and strong circulations can develop, while in the latter the heterogeneity is small and does no longer influence the boundary layer structure. Within each simulation we can now observe the formation of a peak in kinetic energy, which represents the 'optimal' heterogeneity size in the meso-scale, and the subsequent decay of the peak and the development towards the transition to the micro-scale. We have created a non-dimensional parameter space that describes all properties of this system. By studying the previously described evolution for different combinations of parameters, we have derived three important conclusions. First, there exists a horizontal length scale of the heterogeneity (L) that is a function of the boundary layer height (h) and the Richardson (Ri) number of the inversion at the top of the boundary layer. This relationship has the form L = h Ri^(3/8). Second, this horizontal length scale L allows for expressing the time evolution, and thus the state of the system, as a ratio of this length scale and the distance between two patches Xp. This ratio thus describes to which extent the circulation fills up the space that exists between two patch centers. The timings of the transition from the meso- to the micro-scale collapse under this scaling for all simulations sharing the same flux

Priority order in using biomass resources - Energy systems analyses of future scenarios for Denmark

DEFF Research Database (Denmark)

Kwon, Pil Seok; Østergaard, Poul Alberg

2013-01-01

. This article compares the value of using biomass as a heat source and for electricity generation in a 100% renewable energy system context. The comparison is done by assuming an incremental decrease in the biomass available for the electricity and heat sector, respectively. The assumed scenarios......According to some future Danish energy scenarios, biomass will become one of the two main pillars of the future energy system accompanied by wind power. The biomass can be used for generating heat and electricity, and as a transportation fuel in a future energy system according to the scenarios...... for the decrease of biomass are made by use of an hourly energy system analysis model, EnergyPLAN. The results are shown in terms of system configuration, biomass fuel efficiency, system cost, and impacts on the export of electricity. It is concluded that the reduction of biomass in the heat sector is better than...

CFD Modelling of Biomass Combustion in Small-Scale Boilers. Final Report

Energy Technology Data Exchange (ETDEWEB)

Xue-Song Bai; Griselin, Niklas; Klason, Torbern; Nilsson, Johan [Lund Inst. of Tech. (Sweden). Dept. of Heat and Power Engineering

2002-10-01

This project deals with CFD modeling of combustion of wood in fixed bed boilers. A flamelet model for the interaction between turbulence and chemical reactions is developed and applied to study small-scale boiler. The flamelet chemistry employs 43 reactive species and 174 elementary reactions. It gives detailed distributions of important species such as CO and NO{sub x} in the flow field and flue gas. Simulation of a small-scale wood fired boiler measured at SP Boraas (50 KW) shows that the current flamelet model yields results agreeable to the available experimental data. A detailed chemical kinetic model is developed to study the bed combustion process. This model gives boundary conditions for the CFD analysis of gas phase volatile oxidation in the combustion chambers. The model combines a Functional Group submodel with a Depolymerisation, Vaporisation and Crosslinking submodel. The FG submodel simulates how functional groups decompose and form light gas species. The DVC submodell predicts depolymerisation and vaporisation of the macromolecular network and this includes bridge breaking and crosslinking processes, where the wood structure breaks down to fragments. The light fragments form tar and the heavy ones form metaplast. Two boilers firing wood log/chips are studied using the FG-DVC model, one is the SP Boraas small-scale boiler (50 KW) and the other is the Sydkraft Malmoe Vaerme AB's Flintraennan large-scale boiler (55 MW). The fix bed is assumed to be two zones, a partial equilibrium drying/devolatilisation zone and an equilibrium zone. Three typical biomass conversion modes are simulated, a lean fuel combustion mode, a near-stoichiometric combustion and a fuel rich gasification mode. Detailed chemical species and temperatures at different modes are obtained. Physical interpretation is provided. Comparison of the computational results with experimental data shows that the model can reasonably simulate the fixed bed biomass conversion process. CFD

Biomass furnace: projection and construction

Energy Technology Data Exchange (ETDEWEB)

Melo, Fernanda Augusta de Oliveira; Silva, Juarez Sousa e; Silva, Denise de Freitas; Sampaio, Cristiane Pires; Nascimento Junior, Jose Henrique do [Universidade Federal de Vicosa (DEA/UFV), MG (Brazil). Dept. de Engenharia Agricola

2008-07-01

Of all the ways to convert biomass into thermal energy, direct combustion is the oldest. The thermal-chemical technologies of biomass conversion such as pyrolysis and gasification, are currently not the most important alternatives; combustion is responsible for 97% of the bio-energy produced in the world (Demirbas, 2003). For this work, a small furnace was designed and constructed to use biomass as its main source of fuel, and the combustion chamber was coupled with a helical transporter which linked to the secondary fuel reservoir to continually feed the combustion chamber with fine particles of agro-industrial residues. The design of the stove proved to be technically viable beginning with the balance of mass and energy for the air heating system. The proposed heat generator was easily constructed as it made use of simple and easily acquired materials, demanding no specialized labor. (author)

Sensitivities Affecting Heat and Urban Heat Island Effect on Local Scale Projected to Neighborhood Scale in Baltimore, Maryland

Science.gov (United States)

Sze, C.; Zaitchik, B. F.; Scott, A.

2015-12-01

Urban regions are often impacted more by heat than adjacent rural areas, which is a phenomenon known as the urban heat island (UHI) effect. Urban areas are also highly heterogeneous and notoriously difficult to monitor using standard meteorological protocols—the hottest microclimates within a city often occur in locations that lack open, representative installation sites that are an adequate distance from buildings and direct heat sources. To investigate the challenges of monitoring urban heat, this study examines the sensitivity of temperature and humidity sensors currently used in a Baltimore UHI monitoring network to differences in sun exposure, material on which the data collecting instrument is attached, and land cover class of the vicinity. Sensitivity to sun exposure and attachment site can be interpreted as sources of uncertainty for urban heat monitoring, while sensitivity to land cover may reflect a true source of local temperature and humidity variability. In this study, we present results from a test deployment designed to assess the sensitivity of heat measurements to each of these three factors. We then apply these results to interpret measurements taken across the entire Baltimore UHI monitoring network. These results can then be used to improve heat measurements and more accurately represent and quantify the UHI effect on a broader scale, such as in neighborhoods or urban centers.

Energetic and Exergetic Analysis of a Heat Exchanger Integrated in a Solid Biomass-Fuelled Micro-CHP System with an Ericsson Engine

Directory of Open Access Journals (Sweden)

Marie Creyx

2016-04-01

Full Text Available A specific heat exchanger has been developed to transfer heat from flue gas to the working fluid (hot air of the Ericsson engine of a solid biomass-fuelled micro combined heat and power (CHP. In this paper, the theoretical and experimental energetic analyses of this heat exchanger are compared. The experimental performances are described considering energetic and exergetic parameters, in particular the effectiveness on both hot and cold sides. A new exergetic parameter called the exergetic effectiveness is introduced, which allows a comparison between the real and the ideal heat exchanger considering the Second Law of Thermodynamics. A global analysis of exergetic fluxes in the whole micro-CHP system is presented, showing the repartition of the exergy destruction among the components.

Biomass boilers: towards a higher efficiency

International Nuclear Information System (INIS)

Petitot, Pauline; Signoret, Stephane; Mary, Olivier; Dejeu, Mathieu; Tachet, Jean-Pierre

2014-01-01

A set of articles proposes an overview of the situation and perspectives of biomass fuelled boilers in France. As outlined in an interview, professionals are supported by ADEME and the Heat Fund (Fonds Chaleur) for a continuous development of wood-energy in order to reach national objectives for renewable energies by 2020. The next article discusses issues related to wood supply, with some concerns regarding forest exploitation, and needs to find new management ways and to use other sources than forests. The technical status and perspectives of smoke condensation in wood-fuelled boilers are discussed. The example of a malt-house near Issoudun fuelled by biomass since 2013 is presented. Other examples concern a small town of Burgundy which developed and is still improving a heat network, a wood-fuelled heat network in Saint-Denis, and a biomass wood-fuelled heat production plant for the Toulouse University hospital. Graphs indicate evolutions of prices for different wood-based fuel products. The last article outlines the role of forests and the importance of their protection in the struggle against climate change, and discusses problems faced to support this preservation and its financing

Optimal Combustion Conditions for a Small-scale Biomass Boiler

Directory of Open Access Journals (Sweden)

Viktor Plaček

2012-01-01

Full Text Available This paper reports on an attempt to achieve maximum efficiency and lowest possible emissions for a small-scale biomass boiler. This aim can be attained only by changing the control algorithm of the boiler, and in this way not raising the acquisition costs for the boiler. This paper describes the experimental facility, the problems that arose while establishing the facility, and how we have dealt with them. The focus is on discontinuities arising after periodic grate sweeping, and on finding the parameters of the PID control loops. Alongside these methods, which need a lambda probe signal for proper functionality, we inroduce another method, which is able to intercept the optimal combustion working point without the need to use a lambda sensor.

A Thermogravimetric Study of the Behaviour of Biomass Blends During Combustion

Directory of Open Access Journals (Sweden)

Ivo Jiříček

2012-01-01

Full Text Available The ignition and combustion behavior of biomass and biomass blends under typical heating conditions were investigated. Thermogravimetric analyses were performed on stalk and woody biomass, alone and blended with various additive weight ratios. The combustion process was enhanced by adding oxygen to the primary air. This led to shorter devolatilization/pyrolysis and char burnout stages, which both took place at lower temperatures than in air alone. The results of the ignition study of stalk biomass show a decrease in ignition temperature as the particle size decreases. This indicates homogeneous ignition, where the volatiles burn in the gas phase, preventing oxygen from reaching the particle surface.The behavior of biomass fuels in the burning process was analyzed, and the effects of heat production and additive type were investigated. Mixing with additives is a method for modifying biofuel and obtaining a more continuous heat release process. Differential scanning calorimetric-thermogravimetric (DSC-TGA analysis revealed that when the additive is added to biomass, the volatilization rate is modified, the heat release is affected, and the combustion residue is reduced at the same final combustion temperature.

Empirical scaling for present Ohmically heated tokamaks

International Nuclear Information System (INIS)

Daughney, C.

1975-01-01

Experimental results from the Adiabatic Toroidal Compressor (ATC) tokamak are used to obtain empirical scaling laws for the average electron temperature and electron energy confinement time as functions of the average electron density, the effective ion charge, and the plasma current. These scaling laws are extended to include dependence upon minor and major plasma radius and toroidal field strength through a comparison of the various tokamaks described in the literature. Electron thermal conductivity is the dominant loss process for the ATC tokamak. The parametric dependences of the observed electron thermal conductivity are not explained by present theoretical considerations. The electron temperature obtained with Ohmic heating is shown to be a function of current density - which will not be increased in the next generation of large tokamaks. However, the temperature dependence of the electron energy confinement time suggests that significant improvement in confinement time will be obtained with supplementary electron heating. (author)

First Biomass Conference of the Americas: Energy, environment, agriculture, and industry; Proceedings, Volume 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-10-01

This conference was designed to provide a national and international forum to support the development of a viable biomass industry. Although papers on research activities and technologies under development that address industry problems comprised part of this conference, an effort was made to focus on scale-up and demonstration projects, technology transfer to end users, and commercial applications of biomass and wastes. The conference was divided into these major subject areas: Resource Base, Power Production, Transportation Fuels, Chemicals and Products, Environmental Issues, Commercializing Biomass Projects, Biomass Energy System Studies, and Biomass in Latin America. The papers in this first volume deal with Resource Base and Power Production. The particular subjects within the Resource Base area are Biomass, Wastes and Residues, Feedstock Research, and Commercial Systems. The emphasized subjects within the Power Production area are Combustion, Thermal and Biological Gasification, Waste Generation and Waste Disposal and Waste Emissions, and Heat, Steam, and Fuels-Commercial Systems. Selected abstracts have been indexed separately for inclusion in the Energy Science and Technology Database.

Approximations to the Non-Isothermal Distributed Activation Energy Model for Biomass Pyrolysis Using the Rayleigh Distribution

Directory of Open Access Journals (Sweden)

Dhaundiyal Alok

2017-09-01

Full Text Available This paper deals with the influence of some parameters relevant to biomass pyrolysis on the numerical solutions of the nonisothermal nth order distributed activation energy model using the Rayleigh distribution. Investigated parameters are the integral upper limit, the frequency factor, the heating rate, the reaction order and the scale parameters of the Rayleigh distribution. The influence of these parameters has been considered for the determination of the kinetic parameters of the non-isothermal nth order Rayleigh distribution from the experimentally derived thermoanalytical data of biomass pyrolysis.

Biomass combustion for greenhouse carbon dioxide enrichment

International Nuclear Information System (INIS)

Roy, Yves; Lefsrud, Mark; Orsat, Valerie; Filion, Francis; Bouchard, Julien; Nguyen, Quoc; Dion, Louis-Martin; Glover, Antony; Madadian, Edris; Lee, Camilo Perez

2014-01-01

Greenhouses in northern climates have a significant heat requirement that is mainly supplied by non-renewable fuels such as heating oil and natural gas. This project's goal was the development of an improved biomass furnace able to recover the heat and the CO 2 available in the flue gas and use them in the greenhouse. A flue gas purification system was designed, constructed and installed on the chimney of a wood pellet furnace (SBI Caddy Alterna). The purification system consists of a rigid box air filter (MERV rating 14, 0.3 μm pores) followed by two sets of heating elements and a catalytic converter. The air filter removes the particulates present in the flue gas while the heating elements and catalysers transform the noxious gases into less harmful gases. Gas analysis was sampled at different locations in the system using a TESTO 335 flue gas analyzer. The purification system reduces CO concentrations from 1100 cm 3  m −3 to less than 1 cm 3  m −3 NO x from 70 to 5.5 cm 3  m −3 SO 2 from 19 cm 3  m −3 to less than 1 cm 3  m −3 and trapped particulates down to 0.3 μm with an efficiency greater than 95%. These results are satisfactory since they ensure human and plant safety after dilution into the ambient air of the greenhouse. The recuperation of the flue gas has several obvious benefits since it increases the heat usability per unit biomass and it greatly improves the CO 2 recovery of biomass heating systems for the benefit of greenhouse grown plants. - Highlights: • Biomass furnace shows high potential for greenhouse carbon dioxide enrichment. • Flue gas recuperation significantly increases the thermal efficiency of a furnace. • Catalytic converter can reduce CO and NOx below humans and plants exposure limit. • Particulates control is essential to maintain the efficiency of the catalytic conversion. • CO 2 recovery from biomass heating systems reduces farmer's reliance on fossil fuel

Effect of Heating Method on Hydrogen Production by Biomass Gasification in Supercritical Water

Directory of Open Access Journals (Sweden)

Qiuhui Yan

2014-01-01

Full Text Available The glucose as a test sample of biomass is gasified in supercritical water with different heating methods driven by renewable solar energy. The performance comparisons of hydrogen production of glucose gasification are investigated. The relations between temperature raising speed of reactant fluid, variation of volume fraction, combustion enthalpy, and chemical exergy of H2 of the product gases with reactant solution concentration are presented, respectively. The results show that the energy quality of product gases with preheating process is higher than that with no preheating unit for hydrogen production. Hydrogen production quantity and gasification rate of glucose decrease obviously with the increase of concentration of material in no preheating system.

Understanding forest-derived biomass supply with GIS modelling

DEFF Research Database (Denmark)

Hock, B. K.; Blomqvist, L.; Hall, P.

2012-01-01

distribution, and the cost of delivery as forests are frequently remote from energy users. A GIS-based model was developed to predict supply curves of forest biomass material for a site or group of sites, both now and in the future. The GIS biomass supply model was used to assist the New Zealand Energy...... Efficiency and Conservation Authority's development of a national target for biomass use for industrial heat production, to determine potential forest residue volumes for industrial heat and their delivery costs for 19 processing plants of the dairy company Fonterra, and towards investigating options...

Forestry biomass for energy use

International Nuclear Information System (INIS)

Pettenella, D.; Ciccarese, L.

1992-01-01

This paper first analyses the current and potential market in Italy for wood chips and firewood and assesses the potential economic and environmental benefits of the use of forestry biomass. Here, the paper cites the favourable opportunities offered by Italian forestry policies and legislative initiatives for energy saving. The survey of the principal consumers of forestry biomass leads to the identification of three distinct user categories - families living in rural are as requiring wood fuels for space heating, small industrial firms requiring process heat and urban (elite) users with homes furnished with fireplaces in addition to conventional space heating systems. Tabled consumption data going back to the year 1955 and estimated per capita consumption in industrialized countries are used to make comparative market trend analyses. The paper then reviews the current state-of-the-art in wood furnace design by noting the innovative design, performance, operation and maintenance characteristics of key residential and industrial furnace components (feeding systems, combustion chambers, heating boxes, heat exchangers, control systems, deashing systems, etc.). A list of the main Italian wood furnace manufacturers is also included

Emissions from small scale biomass combustion - Research needs

International Nuclear Information System (INIS)

Gustavsson, L.; Karlsson, M.L.; Larfeldt, J.; Leckner, B.

1994-01-01

Earlier investigations have shown that small scale biomass combustion leads to unacceptable emissions in the air. The most important problem is high levels of unburnt hydrocarbons. This report analyzes which are the most important reasons to these emissions and which research efforts that are necessary to increase the knowledge about the combustion processes, thereby promoting the development of environmentally feasible equipment. The following factors are defined as most crucial to emission levels: size of combustion chamber, air excess ratio, means of combustion air supply, mixing between air and fuel, transient events, and fuel quality. It is concluded that both basic and research within the area is needed. More specific, research in the form of systematic analysis of best available technology, reactor experiments, compilation of knowledge about relevant basic combustion processes, mathematical modelling as well as development of measurement techniques are called for. 15 refs, 11 figs, 1 tab

Fiscalini Farms Biomass Energy Project

Energy Technology Data Exchange (ETDEWEB)

William Stringfellow; Mary Kay Camarillo; Jeremy Hanlon; Michael Jue; Chelsea Spier

2011-09-30

waste heat and better documentation of potential of carbon credits, would also improve the economic outlook. Analysis of baseline operational conditions indicated that a reduction in methane emissions and other greenhouse gas savings resulted from implementation of the project. The project results indicate that using anaerobic digestion to produce bio-methane from agricultural biomass is a promising source of electricity, but that significant challenges need to be addressed before dairy-based biomass energy production can be fully integrated into an alternative energy economy. The biomass energy facility was found to be operating undercapacity. Economic analysis indicated a positive economic sustainability, even at the reduced power production levels demonstrated during the baseline period. However, increasing methane generation capacity (via the importation of biomass codigestate) will be critical for increasing electricity output and improving the long-term economic sustainability of the operation. Dairy-based biomass energy plants are operating under strict environmental regulations applicable to both power-production and confined animal facilities and novel approached are being applied to maintain minimal environmental impacts. The use of selective catalytic reduction (SCR) for nitrous oxide control and a biological hydrogen sulfide control system were tested at this facility. Results from this study suggest that biomass energy systems can be compliant with reasonable scientifically based air and water pollution control regulations. The most significant challenge for the development of biomass energy as a viable component of power production on a regional scale is likely to be the availability of energy-rich organic feedstocks. Additionally, there needs to be further development of regional expertise in digester and power plant operations. At the Fiscalini facility, power production was limited by the availability of biomass for methane generation, not the designed

Energy from Waste and Biomass - ALTENER Conference held in Estonia

International Nuclear Information System (INIS)

Roos, Inge

1999-01-01

On November 9-10, 1998 ALTENER Conference Energy from Waste and Biomass took place in the hotel Pirita, Tallinn, Estonia. The Conference was organized by the Swedish National Energy Administration in co-operation with the FEMOPET Estonia and the South Jutland University Centre, Biomass Institute (Denmark). The main topics of the Conference were: collecting biogas from landfall, biogas from municipal sewage treatment, biogas from animal manure, waste heat, biomass from the pulp industry and the sawmill, biomass from forestry, biomass for local and district heating. More than 200 delegates from 14 countries participated in this event. A poster exhibition and two study tours to Paeaeskuela Landfill Plant and Jueri Boiler House were organised too. (author)

Biomass energy utilisation - ecological and economic aspects

International Nuclear Information System (INIS)

Plamen Gramatikov

2009-01-01

Biomass is the world's fourth largest energy source today and it represents about 35% of the primary energy supply in developing countries. Biomass is a versatile source of energy in that it can produce electricity, heat, transport fuel and it can be stored. The problems (technical, economic, etc.) which have to be solved by treatment of biomass are discussed in this work. The average quantities of biomass resources of some European countries are presented and the structure, percentage of products and their calorific values are estimated. Keywords: Biomass Energy Potential, Ecological & Economic Aspects

Monitoring of the energy performance of a district heating CHP plant based on biomass boiler and ORC generator

International Nuclear Information System (INIS)

Prando, Dario; Renzi, Massimiliano; Gasparella, Andrea; Baratieri, Marco

2015-01-01

More than seventy district heating (DH) plants based on biomass are operating in South Tyrol (Italy) and most of them supply heat to residential districts. Almost 20% of them are cogenerative systems, thus enabling primary energy savings with respect to the separate production of heat and power. However, the actual performance of these systems in real operation can considerably differ from the nominal one. The main objectives of this work are the assessment of the energy performance of a biomass boiler coupled with an Organic Rankine Cycle (i.e. ORC) generator under real operating conditions and the identification of its potential improvements. The fluxes of energy and mass of the plant have been measured onsite. This experimental evaluation has been supplemented with a thermodynamic model of the ORC generator, calibrated with the experimental data, which is capable to predict the system performance under different management strategies of the system. The results have highlighted that a decrease of the DH network temperature of 10 °C can improve the electric efficiency of the ORC generator of one percentage point. Moreover, a DH temperature reduction could decrease the main losses of the boiler, namely the exhaust latent thermal loss and the exhaust sensible thermal loss, which account for 9% and 16% of the boiler input power, respectively. The analysis of the plant has pointed out that the ORC pump, the flue gases extractor, the thermal oil pump and the condensation section fan are the main responsible of the electric self-consumption. Finally, the negative effect of the subsidisation on the performance of the plant has been discussed. - Highlights: • Energy performance of a biomass boiler coupled to an ORC turbine in real operation. • Potential improvements of a CHP plant connected to a DH network. • Performance prediction by means of a calibrated ORC thermodynamic model. • Influence of the DH temperature on the electric efficiency. • Impact of the

Thermo-mechanical efficiency of the bimetallic strip heat engine at the macro-scale and micro-scale

International Nuclear Information System (INIS)

Arnaud, A; Boughaleb, J; Monfray, S; Boeuf, F; Skotnicki, T; Cugat, O

2015-01-01

Bimetallic strip heat engines are energy harvesters that exploit the thermo-mechanical properties of bistable bimetallic membranes to convert heat into mechanical energy. They thus represent a solution to transform low-grade heat into electrical energy if the bimetallic membrane is coupled with an electro-mechanical transducer. The simplicity of these devices allows us to consider their miniaturization using MEMS fabrication techniques. In order to design and optimize these devices at the macro-scale and micro-scale, this article proposes an explanation of the origin of the thermal snap-through by giving the expressions of the constitutive equations of composite beams. This allows us to evaluate the capability of bimetallic strips to convert heat into mechanical energy whatever their size is, and to give the theoretical thermo-mechanical efficiencies which can be obtained with these harvesters. (paper)

An experimental study on micro-scale flow boiling heat transfer

International Nuclear Information System (INIS)

Tibirica, Cristiano Bigonha; Ribatski, Gherhardt

2009-01-01

In this paper, new experimental flow boiling heat transfer results in micro-scale tubes are presented. The experimental data were obtained in a horizontal 2.32 mm I.D. stainless steel tube with heating length of 464 mm, R134a as working fluid, mass velocities ranging from 50 to 600 kg/m 2 s, heat flux from 5 to 55 kW/m 2 , exit saturation temperatures of 22, 31 and 41 deg C, and vapor qualities from 0.05 to 0.98. Flow pattern characterization was also performed from images obtained by high speed filming. Heat transfer coefficient results from 2 to 14 kW/m 2 K were measured. It was found that the heat transfer coefficient is a strong function of the saturation pressure, heat flux, mass velocity and vapor quality. The experimental data were compared against the following micro-scale flow boiling predictive methods from the literature: Saitoh et al., Kandlikar, Zhang et al. and Thome et al. Comparisons against these methods based on the data segregated according to flow patterns were also performed. Though not satisfactory, Saitoh et al. worked the best and was able of capturing most of the experimental heat transfer trends. (author)

An experimental study on micro-scale flow boiling heat transfer

Energy Technology Data Exchange (ETDEWEB)

Tibirica, Cristiano Bigonha; Ribatski, Gherhardt [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Escola de Engenharia. Dept. de Engenharia Mecanica

2009-07-01

In this paper, new experimental flow boiling heat transfer results in micro-scale tubes are presented. The experimental data were obtained in a horizontal 2.32 mm I.D. stainless steel tube with heating length of 464 mm, R134a as working fluid, mass velocities ranging from 50 to 600 kg/m{sup 2}s, heat flux from 5 to 55 kW/m{sup 2}, exit saturation temperatures of 22, 31 and 41 deg C, and vapor qualities from 0.05 to 0.98. Flow pattern characterization was also performed from images obtained by high speed filming. Heat transfer coefficient results from 2 to 14 kW/m{sup 2}K were measured. It was found that the heat transfer coefficient is a strong function of the saturation pressure, heat flux, mass velocity and vapor quality. The experimental data were compared against the following micro-scale flow boiling predictive methods from the literature: Saitoh et al., Kandlikar, Zhang et al. and Thome et al. Comparisons against these methods based on the data segregated according to flow patterns were also performed. Though not satisfactory, Saitoh et al. worked the best and was able of capturing most of the experimental heat transfer trends. (author)

A model for allometric scaling of mammalian metabolism with ambient heat loss

KAUST Repository

Kwak, Ho Sang; Im, Hong G.; Shim, Eun Bo

2016-01-01

The finding that additional radiative heat loss and the consideration of an outer insulation fur layer attenuate these deviation effects and render the scaling law closer to 2/3 provides in silico evidence for a functional impact of heat transfer mode on the allometric scaling law in mammalian metabolism.

Impact of electro-magnetic stabilization, small- scale turbulence and multi-scale interactions on heat transport in JET

Science.gov (United States)

Mantica, Paola

2016-10-01

Heat transport experiments in JET, based on ICRH heat flux scans and temperature modulation, have confirmed the importance of two transport mechanisms that are often neglected in modeling experimental results, but are crucial to reach agreement between theory and experiment and may be significant in ITER. The first mechanism is the stabilizing effect of the total pressure gradient (including fast ions) on ITG driven ion heat transport. Such stabilization is found in non-linear gyro-kinetic electro-magnetic simulations using GENE and GYRO, and is the explanation for the observed loss of ion stiffness in the core of high NBI-power JET plasmas. The effect was recently observed also in JET plasmas with dominant ICRH heating and small rotation, due to ICRH fast ions, which is promising for ITER. Such mechanism dominates over ExB flow shear in the core and needs to be included in quasi-linear models to increase their ability to capture the relevant physics. The second mechanism is the capability of small- scale ETG instabilities to carry a significant fraction of electron heat. A decrease in Te peaking is observed when decreasing Zeff Te/Ti, which cannot be ascribed to TEMs but is in line with ETGs. Non-linear GENE single-scale simulations of ETGs and ITG/TEMs show that the ITG/TEM electron heat flux is not enough to match experiment. TEM stiffness is also much lower than measured. In the ETG single scale simulations the external flow shear is used to saturate the ETG streamers. Multi-scale simulations are ongoing, in which the ion zonal flows are the main saturating mechanism for ETGs. These costly simulations should provide the final answer on the importance of ETG-driven electron heat flux in JET. with JET contributors [F.Romanelli, Proc.25thIAEA FEC]. Supported by EUROfusion Grant 633053.

Biomass energy in the making

International Nuclear Information System (INIS)

Anon.

2008-01-01

Wood, straw, agricultural residues, organic wastes, biomass is everywhere you look. But the efficient use of this source of green electricity - the world's second largest renewable energy source - requires optimization of biomass collection and combustion processes. Biomass is back on the political agenda. In mid-June of this year, the French government gave this renewable energy a boost by selecting twenty-two projects to generate power and heat with biomass. The plants, to be commissioned by 2010, will be located in eleven different regions and will consume energy from organic plant matter. The power generated will be bought at a firm price of 128 euros per megawatt-hour. Most of the fuel will come from forest and paper industry waste, but straw and even grape pomace will be used in some cases. The plants will have a combined generating capacity of 300 MWh, raising France's installed biomass capacity to a total of 700 MWe. A drop of water in the ocean in the overall scheme of France's electricity. It is true that France has long neglected biomass. In 2004, electricity generated from biological resources represented a mere 1.74 TWhe in France, just 0.3% of its power consumption. This will rise to 0.6% once the new plants have come on line. The trend is the same in all of the EU's 27 member states, according to Eurostat, the statistical office of the European Communities: the amount of electricity generated from biomass (including biogas, municipal waste and wood) has practically doubled in six years, rising from 40 to 80 TWhe between 2000 and 2005. This is an improvement, but it still only represents 2.5% of the electricity supplied to Europeans. On a global scale, biomass contributes just 1% of total electric power generation. Yet biomass is an energy resource found all over the world, whether as agricultural waste, wood chips, or dried treatment plant sludge, to name but a few. Biomass power plants have managed to gain a foothold mainly in countries that produce

Ethanol Production from Biomass: Large Scale Facility Design Project

Energy Technology Data Exchange (ETDEWEB)

Berson, R. Eric [Univ. of Louisville, KY (United States)

2009-10-29

High solids processing of biomass slurries provides the following benefits: maximized product concentration in the fermentable sugar stream, reduced water usage, and reduced reactor size. However, high solids processing poses mixing and heat transfer problems above about 15% for pretreated corn stover solids due to their high viscosities. Also, highly viscous slurries require high power consumption in conventional stirred tanks since they must be run at high rotational speeds to maintain proper mixing. An 8 liter scraped surface bio-reactor (SSBR) is employed here that is designed to efficiently handle high solids loadings for enzymatic saccharification of pretreated corn stover (PCS) while maintaining power requirements on the order of low viscous liquids in conventional stirred tanks. Saccharification of biomass exhibit slow reaction rates and incomplete conversion, which may be attributed to enzyme deactivation and loss of activity due to a variety of mechanisms. Enzyme deactivation is classified into two categories here: one, deactivation due to enzyme-substrate interactions and two, deactivation due to all other factors that are grouped together and termed “non-specific” deactivation. A study was conducted to investigate the relative extents of “non-specific” deactivation and deactivation due to “enzyme-substrate interactions” and a model was developed that describes the kinetics of cellulose hydrolysis by considering the observed deactivation effects. Enzyme substrate interactions had a much more significant effect on overall deactivation with a deactivation rate constant about 20X higher than the non-specific deactivation rate constant (0.35 h^-1 vs 0.018 h^-1). The model is well validated by the experimental data and predicts complete conversion of cellulose within 30 hours in the absence of enzyme substrate interactions.

An empirical, integrated forest biomass monitoring system

Science.gov (United States)

Kennedy, Robert E.; Ohmann, Janet; Gregory, Matt; Roberts, Heather; Yang, Zhiqiang; Bell, David M.; Kane, Van; Hughes, M. Joseph; Cohen, Warren B.; Powell, Scott; Neeti, Neeti; Larrue, Tara; Hooper, Sam; Kane, Jonathan; Miller, David L.; Perkins, James; Braaten, Justin; Seidl, Rupert

2018-02-01

The fate of live forest biomass is largely controlled by growth and disturbance processes, both natural and anthropogenic. Thus, biomass monitoring strategies must characterize both the biomass of the forests at a given point in time and the dynamic processes that change it. Here, we describe and test an empirical monitoring system designed to meet those needs. Our system uses a mix of field data, statistical modeling, remotely-sensed time-series imagery, and small-footprint lidar data to build and evaluate maps of forest biomass. It ascribes biomass change to specific change agents, and attempts to capture the impact of uncertainty in methodology. We find that: • A common image framework for biomass estimation and for change detection allows for consistent comparison of both state and change processes controlling biomass dynamics. • Regional estimates of total biomass agree well with those from plot data alone. • The system tracks biomass densities up to 450-500 Mg ha-1 with little bias, but begins underestimating true biomass as densities increase further. • Scale considerations are important. Estimates at the 30 m grain size are noisy, but agreement at broad scales is good. Further investigation to determine the appropriate scales is underway. • Uncertainty from methodological choices is evident, but much smaller than uncertainty based on choice of allometric equation used to estimate biomass from tree data. • In this forest-dominated study area, growth and loss processes largely balance in most years, with loss processes dominated by human removal through harvest. In years with substantial fire activity, however, overall biomass loss greatly outpaces growth. Taken together, our methods represent a unique combination of elements foundational to an operational landscape-scale forest biomass monitoring program.

75 FR 6263 - Biomass Crop Assistance Program

Science.gov (United States)

2010-02-08

... guidelines followed for any harvesting, collecting, storing or transporting of such material from such... for the purposes of transport and delivery to eligible biomass conversion facilities. As specified in... or proposes to convert renewable biomass into heat, power, biobased products, advanced biodiesel, or...

Natural convection solar dryer with biomass back-up heater

Energy Technology Data Exchange (ETDEWEB)

Bena, B.; Fuller, R.J. [University of Melbourne (Australia). Faculty of Engineering

2002-07-01

A direct-type natural convection solar dryer and a simple biomass burner have been combined to demonstrate a drying technology suitable for small-scale processors of dried fruits and vegetables in non-electrified areas of developing countries. From a series of evaluation trials of the system, the capacity of the dryer was found to be 20-22kg of fresh pineapple arranged in a single layer of 0.01-m-thick slices. The overall drying efficiency of the unit was calculated to be {approx} 9%. During the same trial, the drying efficiency of the solar component alone was found to be 22%. Other trials estimated the efficiency of the burner in producing useful heat for drying to be 27%. Key features of the biomass burner were found to be the addition of thermal mass on the upper surface, an internal baffle plate to lengthen the exhaust gas exit path and a variable air inlet valve. Further modifications to further improve the performance of both the solar and biomass components of the dryer are suggested. (author)

New energy technologies 3 - Geothermal and biomass energies

International Nuclear Information System (INIS)

Sabonnadiere, J.C.; Alazard-Toux, N.; His, S.; Douard, F.; Duplan, J.L.; Monot, F.; Jaudin, F.; Le Bel, L.; Labeyrie, P.

2007-01-01

This third tome of the new energy technologies handbook is devoted to two energy sources today in strong development: geothermal energy and biomass fuels. It gives an exhaustive overview of the exploitation of both energy sources. Geothermal energy is presented under its most common aspects. First, the heat pumps which encounter a revival of interest in the present-day context, and the use of geothermal energy in collective space heating applications. Finally, the power generation of geothermal origin for which big projects exist today. The biomass energies are presented through their three complementary aspects which are: the biofuels, in the hypothesis of a substitutes to fossil fuels, the biogas, mainly produced in agricultural-type facilities, and finally the wood-fuel which is an essential part of biomass energy. Content: Forewords; geothermal energy: 1 - geothermal energy generation, heat pumps, direct heat generation, power generation. Biomass: 2 - biofuels: share of biofuels in the energy context, present and future industries, economic and environmental status of biofuel production industries; 3 - biogas: renewable natural gas, involuntary bio-gases, man-controlled biogas generation, history of methanation, anaerobic digestion facilities or biogas units, biogas uses, stakes of renewable natural gas; 4 - energy generation from wood: overview of wood fuels, principles of wood-energy conversion, wood-fueled thermal energy generators. (J.S.)

Experimental investigation on combustion and heat transfer characteristics in a furnace fueled with unconventional biomass fuels (date stones and palm stalks)

International Nuclear Information System (INIS)

Al-Omari, S.-A.B.

2006-01-01

The combustion of date stones and palm stalks in a small scale furnace with a conical solid fuel bed is investigated experimentally. This investigation (to the best of the knowledge of the author) is the first addressing date stones as a new renewable energy source. Different experimental conditions are investigated where different fuel feed conditions and different combustion air flow rates are considered. The major results are given in terms of the fuel reduction rates and the heat transferred to the cooling water flowing in a water jacket around the furnace as functions of time. Combustion of the biomass fuels considered here in the investigated furnace is initiated by using LPG fuel as a starter. The hot products of LPG combustion, which is taking place in a burner built prior to the investigated solid fuel furnace, are allowed to penetrate the conical fuel bed for 2-3 min from its bottom base in the upward direction, causing effective heating and gasification and pyrolysis of the solid fuel in the bed to take place. The resulting combustible gases mix with the combustion air and subsequently are ignited by an external ignition source. The results of the present study highlight date stones as a renewable energy source with a good potential

Thermal non-equilibrium heat transfer in a porous cavity in the presence of bio-chemical heat source

Directory of Open Access Journals (Sweden)

Nazari Mohsen

2015-01-01

Full Text Available This paper is concerned with thermal non-equilibrium natural convection in a square cavity filled with a porous medium in the presence of a biomass which is transported in the cavity. The biomass can consume a secondary moving substrate. The physics of the presented problem is related to the analysis of heat and mass transfer in a composting process that controlled by internal heat generation. The intensity of the bio-heat source generated in the cavity is equal to the rate of consumption of the substrate by the biomass. It is assumed that the porous medium is homogeneous and isotropic. A two-field model that represents the fluid and solid phase temperature fields separately is used for energy equation. A simplified Monod model is introduced along with the governing equations to describe the consumption of the substrate by the biomass. In other word, the transient biochemical heat source which is dependent on a solute concentration is considered in the energy equations. Investigation of the biomass activity and bio-chemical heat generation in the case of thermal non-equilibrium assumption has not been considered in the literature and they are open research topics. The effects of thermal non-equilibrium model on heat transfer, flow pattern and biomass transfer are investigated. The effective parameters which have a direct impact on the generated bio-chemical heat source are also presented. The influences of the non-dimensional parameters such as fluid-to-solid conductivity ratio on the temperature distribution are presented.

Method for creating high carbon content products from biomass oil

Science.gov (United States)

Parker, Reginald; Seames, Wayne

2012-12-18

In a method for producing high carbon content products from biomass, a biomass oil is added to a cracking reactor vessel. The biomass oil is heated to a temperature ranging from about 100.degree. C. to about 800.degree. C. at a pressure ranging from about vacuum conditions to about 20,700 kPa for a time sufficient to crack the biomass oil. Tar is separated from the cracked biomass oil. The tar is heated to a temperature ranging from about 200.degree. C. to about 1500.degree. C. at a pressure ranging from about vacuum conditions to about 20,700 kPa for a time sufficient to reduce the tar to a high carbon content product containing at least about 50% carbon by weight.

Modeling integrated biomass gasification business concepts

Science.gov (United States)

Peter J. Ince; Ted Bilek; Mark A. Dietenberger

2011-01-01

Biomass gasification is an approach to producing energy and/or biofuels that could be integrated into existing forest product production facilities, particularly at pulp mills. Existing process heat and power loads tend to favor integration at existing pulp mills. This paper describes a generic modeling system for evaluating integrated biomass gasification business...

Commercial demonstration of atmospheric medium BTU fuel gas production from biomass without oxygen the Burlington, Vermont Project

Energy Technology Data Exchange (ETDEWEB)

Rohrer, J.W. [Zurn/NEPCO, South Portland, MA (United States); Paisley, M. [Battelle Laboratories, Columbus, OH (United States)

1995-12-31

The first U.S. demonstration of a gas turbine operating on fuel gas produced by the thermal gasification of biomass occurred at Battelle Columbus Labs (BCL) during 1994 using their high throughput indirect medium Btu gasification Process Research Unit (PRU). Zurn/NEPCO was retained to build a commercial scale gas plant utilizing this technology. This plant will have a throughput rating of 8 to 12 dry tons per hour. During a subsequent phase of the Burlington project, this fuel gas will be utilized in a commercial scale gas turbine. It is felt that this process holds unique promise for economically converting a wide variety of biomass feedstocks efficiently into both a medium Btu (500 Btu/scf) gas turbine and IC engine quality fuel gas that can be burned in engines without modification, derating or efficiency loss. Others are currently demonstrating sub-commercial scale thermal biomass gasification processes for turbine gas, utilizing both atmospheric and pressurized air and oxygen-blown fluid bed processes. While some of these approaches hold merit for coal, there is significant question as to whether they will prove economically viable in biomass facilities which are typically scale limited by fuel availability and transportation logistics below 60 MW. Atmospheric air-blown technologies suffer from large sensible heat loss, high gas volume and cleaning cost, huge gas compressor power consumption and engine deratings. Pressurized units and/or oxygen-blown gas plants are extremely expensive for plant scales below 250 MW. The FERCO/BCL process shows great promise for overcoming the above limitations by utilizing an extremely high throughout circulation fluid bed (CFB) gasifier, in which biomass is fully devolitalized with hot sand from a CFB char combustor. The fuel gas can be cooled and cleaned by a conventional scrubbing system. Fuel gas compressor power consumption is reduced 3 to 4 fold verses low Btu biomass gas.

Developing business in emerging biomass energy markets

International Nuclear Information System (INIS)

Kadyszewski, J.

2005-01-01

Global market trends for forest products were reviewed in this PowerPoint presentation. The status of biomass energy products in relation to climate change and renewable energy portfolio standards was also examined. It was noted that China has increased investment in processing capacity and has increased imports of raw logs. India has doubled its imports of raw logs. Details of major tropical log producers and consumers were presented. Details of the biomass industry in the United States were presented, as well as data on fuel use at biomass energy plants and biomass energy capacity. An overview of biomass energy in the Russian far east and Siberia was presented, as well as details of activities and opportunities in Brazil and Indonesia. An economic analysis for small dry kilns was presented. Issues concerning boiler capacity in Russian companies for 2001-2005 were discussed. A case study of a biomass project from Congo was presented. It was noted that projects that replace fossil fuels can obtain revenues from the sale of carbon benefits, and that biomass energy offers the most attractive current option for the removal of carbon dioxide (CO 2 ) from the atmosphere. Details of a district heating project in Siberia were presented, and it was noted that in remote regions, costs for heat and power from biomass can be lower than costs from diesel and coal. It was concluded that there will be significant growth for biomass energy systems in the developing world, and that climate change will be an increasingly important element in advancing biomass energy. tabs., figs

EnerGEO biomass pilot

International Nuclear Information System (INIS)

Tum, M.; Guenther, K.P.; McCallum, I.; Balkovic, J.; Khabarov, N.; Kindermann, G.; Leduc, S.; Biberacher, M.

2013-01-01

In the framework of the EU FP7 project EnerGEO (Earth Observations for Monitoring and Assessment of the Environmental Impact of Energy Use) sustainable energy potentials for forest and agricultural areas were estimated by applying three different model approaches. Firstly, the Biosphere Energy Transfer Hydrology (BETHY/DLR) model was applied to assess agricultural and forest biomass increases on a regional scale with the extension to grassland. Secondly, the EPIC (Environmental Policy Integrated Climate) - a cropping systems simulation model - was used to estimate grain yields on a global scale and thirdly the Global Forest Model (G4M) was used to estimate global woody biomass harvests and stock. The general objective of the biomass pilot is to implement the observational capacity for using biomass as an important current and future energy resource. The scope of this work was to generate biomass energy potentials for locations on the globe and to validate these data. Therefore, the biomass pilot was focused to use historical and actual remote sensing data as input data for the models. For validation purposes, forest biomass maps for 1987 and 2002 for Germany (Bundeswaldinventur (BWI-2)) and 2001 and 2008 for Austria (Austrian Forest Inventory (AFI)) were prepared as reference. (orig.)

EnerGEO biomass pilot

Energy Technology Data Exchange (ETDEWEB)

Tum, M.; Guenther, K.P. [German Aerospace Center (DLR), Wessling (Germany). German Remote Sensing Data Center (DFD); McCallum, I.; Balkovic, J.; Khabarov, N.; Kindermann, G.; Leduc, S. [International Institute for Applied Systems Analysis (IIASA), Laxenburg (Austria); Biberacher, M. [Research Studios Austria AG (RSA), Salzburg (Austria)

2013-07-01

In the framework of the EU FP7 project EnerGEO (Earth Observations for Monitoring and Assessment of the Environmental Impact of Energy Use) sustainable energy potentials for forest and agricultural areas were estimated by applying three different model approaches. Firstly, the Biosphere Energy Transfer Hydrology (BETHY/DLR) model was applied to assess agricultural and forest biomass increases on a regional scale with the extension to grassland. Secondly, the EPIC (Environmental Policy Integrated Climate) - a cropping systems simulation model - was used to estimate grain yields on a global scale and thirdly the Global Forest Model (G4M) was used to estimate global woody biomass harvests and stock. The general objective of the biomass pilot is to implement the observational capacity for using biomass as an important current and future energy resource. The scope of this work was to generate biomass energy potentials for locations on the globe and to validate these data. Therefore, the biomass pilot was focused to use historical and actual remote sensing data as input data for the models. For validation purposes, forest biomass maps for 1987 and 2002 for Germany (Bundeswaldinventur (BWI-2)) and 2001 and 2008 for Austria (Austrian Forest Inventory (AFI)) were prepared as reference. (orig.)

Utilization of low-temperature heat sources for heat and power production

DEFF Research Database (Denmark)

Haglind, Fredrik; Elmegaard, Brian

2014-01-01

Low-temperature heat sources are available in many applications, ranging from waste heat from marine diesel engines, industries and refrigeration plants to biomass, geothermal and solar heat sources. There is a great potential for enhancing the utilization of these heat sources by novel...

The role of large‐scale heat pumps for short term integration of renewable energy

DEFF Research Database (Denmark)

Mathiesen, Brian Vad; Blarke, Morten; Hansen, Kenneth

2011-01-01

technologies is focusing on natural working fluid hydrocarbons, ammonia, and carbon dioxide. Large-scale heat pumps are crucial for integrating 50% wind power as anticipated to be installed in Denmark in 2020, along with other measures. Also in the longer term heat pumps can contribute to the minimization...... savings with increased wind power and may additionally lead to economic savings in the range of 1,500-1,700 MDKK in total in the period until 2020. Furthermore, the energy system efficiency may be increased due to large heat pumps replacing boiler production. Finally data sheets for large-scale ammonium......In this report the role of large-scale heat pumps in a future energy system with increased renewable energy is presented. The main concepts for large heat pumps in district heating systems are outlined along with the development for heat pump refrigerants. The development of future heat pump...

Improved prediction of higher heating value of biomass using an artificial neural network model based on proximate analysis.

Science.gov (United States)

Uzun, Harun; Yıldız, Zeynep; Goldfarb, Jillian L; Ceylan, Selim

2017-06-01

As biomass becomes more integrated into our energy feedstocks, the ability to predict its combustion enthalpies from routine data such as carbon, ash, and moisture content enables rapid decisions about utilization. The present work constructs a novel artificial neural network model with a 3-3-1 tangent sigmoid architecture to predict biomasses' higher heating values from only their proximate analyses, requiring minimal specificity as compared to models based on elemental composition. The model presented has a considerably higher correlation coefficient (0.963) and lower root mean square (0.375), mean absolute (0.328), and mean bias errors (0.010) than other models presented in the literature which, at least when applied to the present data set, tend to under-predict the combustion enthalpy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Energetic potential of algal biomass from high-rate algal ponds for the production of solid biofuels.

Science.gov (United States)

Costa, Taynan de Oliveira; Calijuri, Maria Lúcia; Avelar, Nayara Vilela; Carneiro, Angélica de Cássia de Oliveira; de Assis, Letícia Rodrigues

2017-08-01

In this investigation, chemical characteristics, higher, lower and net heating value, bulk and energy density, and thermogravimetric analysis were applied to study the thermal characteristics of three algal biomasses. These biomasses, grown as by-products of wastewater treatment in high-rate algal ponds (HRAPs), were: (i) biomass produced in domestic effluent and collected directly from an HRAP (PO); (ii) biomass produced in domestic effluent in a mixed pond-panel system and collected from the panels (PA); and (iii) biomass originating from the treatment effluent from the meat processing industry and collected directly from an HRAP (IN). The biomass IN was the best alternative for thermal power generation. Subsequently, a mixture of the algal biomasses and Jatropha epicarp was used to produce briquettes containing 0%, 25%, 50%, 75%, and 100% of algal biomass, and their properties were evaluated. In general, the addition of algal biomass to briquettes decreased both the hygroscopicity and fixed carbon content and increased the bulk density, ash content, and energy density. A 50% proportion of biomass IN was found to be the best raw material for producing briquettes. Therefore, the production of briquettes consisting of algal biomass and Jatropha epicarp at a laboratory scale was shown to be technically feasible.

Experience of more than 1000 h of operation with oxygen carriers and solid biomass at large scale

International Nuclear Information System (INIS)

Berdugo Vilches, Teresa; Lind, Fredrik; Rydén, Magnus; Thunman, Henrik

2017-01-01

Highlights: • First large scale experience (MW) of biomass combustion at CLC-relevant conditions. • Manganese and ilmenite were applied successfully at semi-industrial scale. • 60% combustion under challenging conditions: 830 °C, over-bed fuel feeding. • Volatiles conversion limited by mixing to a significant extent. - Abstract: This paper presents an overview of the experience gained from operating a dual fluidized bed system with oxygen carriers and biomass for more than 1000 h. The tests were carried out in the Chalmers boiler/gasifier loop (with inputs of 12 MW_t_h and 2–4 MW_t_h, respectively), which is 2–4 orders of magnitude larger than most existing CLC units. Coarse biomass particles (i.e., commercial wood pellets) were fed as fuel onto the surface of a mild fluidized bed. This limits significantly the contacts between the volatiles and the oxygen carrier particles, as the flotsam fuel tends to remain on the surface of the bed while the volatiles are released. The oxygen carrier materials tested were ilmenite and a manganese ore. The influences on biomass conversion of fluidization velocity, fuel feeding rate, and circulation rate of the bed material were investigated. Both bed materials efficiently transported oxygen between the reactors, achieving up to 60% combustion of the gases released in the reactor at a relatively low temperature, i.e., 830 °C. The ilmenite outperformed the manganese ore under the conditions investigated. With oxygen carriers, the yield of hydrocarbons heavier than benzene was in the range of 10–11 g/N m"3, which was 70% (w/w) lower than that obtained in a reference case with silica-sand as the bed material. The conversion of volatile species to CO_2 was limited by gas-solids mixing, which could be enhanced by altering the fluidization velocity. The circulation rate of the bed material and the fuel feeding rate were found to have important influences on the rate of char gasification. Given the relatively low

Indoor exposure to particles emitted by biomass-burning heating systems and evaluation of dose and lung cancer risk received by population.

Science.gov (United States)

Stabile, L; Buonanno, G; Avino, P; Frattolillo, A; Guerriero, E

2018-04-01

Homes represent a critical microenvironment in terms of air quality due to the proximity to main particle sources and the lack of proper ventilation systems. Biomass-fed heating systems are still extensively used worldwide, then likely emitting a significant amount of particles in indoor environments. Nonetheless, research on biomass emissions are limited to their effects on outdoor air quality then not properly investigating the emission in indoor environments. To this purpose, the present paper aims to evaluate the exposure to different airborne particle metrics (including both sub- and super-micron particles) and attached carcinogenic compounds in dwellings where three different heating systems were used: open fireplaces, closed fireplaces and pellet stoves. Measurements in terms of particle number, lung-deposited surface area, and PM fraction concentrations were measured during the biomass combustion activities, moreover, PM 10 samples were collected and chemically analyzed to obtain mass fractions of carcinogenic compounds attached onto particles. Airborne particle doses received by people exposed in such environments were evaluated as well as their excess lung cancer risk. Most probable surface area extra-doses received by people exposed to open fireplaces on hourly basis (56 mm 2  h -1 ) resulted one order of magnitude larger than those experienced for exposure to closed fireplaces and pellet stoves. Lifetime extra risk of Italian people exposed to the heating systems under investigation were larger than the acceptable lifetime risk (10 -5 ): in particular, the risk due to the open fireplace (8.8 × 10 -3 ) was non-negligible when compared to the overall lung cancer risk of typical Italian population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Energy confinement scaling in tokamaks: some implications of recent experiments with ohmic and strong auxiliary heating

International Nuclear Information System (INIS)

Goldston, R.J.

1984-02-01

Recent results from confinement scaling experiments on tokamaks with ohmic and strong auxiliary heating are reviewed. An attempt is made to draw these results together into a low-density ohmic confinement scaling law, and a scaling law for confinement with auxiliary heating. The auxiliary heating confinement law may also serve to explain the saturation in tau/sub E/ vs anti n/sub e/ observed in some ohmic heating density scaling experiments

Feasibility of waste to Bio-diesel production via Nuclear-Biomass hybrid model. System dynamics analysis

International Nuclear Information System (INIS)

Nam, Hoseok; Kasada, Ryuta; Konishi, Satoshi

2017-01-01

Nuclear-Biomass hybrid system which takes waste biomass from municipal, agricultural area, and forest as feedstock produces Bio-diesel fuel from synthesis gas generated by endothermic pyrolytic gasification using high temperature nuclear heat. Over 900 degree Celsius of exterior thermal heat from nuclear reactors, Very High Temperature Reactor (VHTR) and some other heat sources, bring about waste biomass gasification to produce maximum amount of chemical energy from feedstock. Hydrogen from Biomass gasification or Bio-diesel as the product of Fischer-Tropsch reaction following it provide fuels for transport sector. Nuclear-Biomass hybrid system is a new alternatives to produce more energy generating synergy effects by efficiently utilizing the high temperature heat from nuclear reactor that might be considerably wasted by thermal cycle, and also energy loss from biomass combustion or biochemical processes. System Dynamics approach is taken to analyze low-carbon synthesis fuel, Bio-diesel, production with combination of carbon monoxide and hydrogen from biomass gasification. Feedstock cost considering collection, transportation, storage and facility for biomass gasification impacts the economic feasibility of this model. This paper provides the implication of practical nuclear-biomass hybrid system application with feedstock supply chain through evaluation of economic feasibility. (author)

The influence of the size of the CHP (combined heat and power) system integrated with a biomass fueled gas generator and piston engine on the thermodynamic and economic effectiveness of electricity and heat generation

International Nuclear Information System (INIS)

Skorek-Osikowska, Anna; Bartela, Łukasz; Kotowicz, Janusz; Sobolewski, Aleksander; Iluk, Tomasz; Remiorz, Leszek

2014-01-01

This paper analyzes the possibility and the cost of using gas from biomass gasification in the production of electricity and generation of heat using a piston engine in which the power in the supplied biomass is no more than 50 MW. A mathematical model that allows for thermodynamic and economic analysis was designed. The input data regarding the gas generator and the process gas were collected in real experiments on the research installation. Electricity and heat production efficiencies and the electric and heat power of the system were primarily used as indicators of the thermodynamic effectiveness. For the economic analysis, discount methods were adopted that consider the legal and economic environment of such investments. Given the assumptions, the analysis shows that positive economic indicators can characterize the considered systems. The work also included sensitivity analysis of change of the selected characteristic quantities on the evaluation indices. The economic viability of such systems is strongly influenced by many factors, mainly price of fuel and green certificates. When the price of fuel is higher than 9.62 €/GJ or the price of certificates lower than 26.75 €/MWh the NPV (net present value) and NPVR (net present value ratio) indices do not reach positive values for any size of installation. - Highlights: • CHP systems integrated with biomass gasification and piston engine(s) were examined. • An experiment with a biomass-fed gasifier was conducted and the data were used for calculations. • The conditions for economic profitability were determined. • Sensitivity analyses of the influence of the selected quantities were performed. • Price of green certificates and price of fuel are the most important for economic viability

Heating-insensitive scale increase caused by convective precipitation

Science.gov (United States)

Haerter, Jan; Moseley, Christopher; Berg, Peter

2017-04-01

The origin of intense convective extremes and their unusual temperature dependence has recently challenged traditional thermodynamic arguments, based on the Clausius-Clapeyron relation. In a sequence of studies (Lenderink and v. Mejgaard, Nat Geosc, 2008; Berg, Haerter, Moseley, Nat Geosc, 2013; and Moseley, Hohenegger, Berg, Haerter, Nat Geosc, 2016) the argument of convective-type precipitation overcoming the 7%/K increase in extremes by dynamical, rather than thermodynamic, processes has been promoted. How can the role of dynamical processes be approached for precipitating convective cloud? One-phase, non-precipitating Rayleigh-Bénard convection is a classical problem in complex systems science. When a fluid between two horizontal plates is sufficiently heated from below, convective rolls spontaneously form. In shallow, non-precipitating atmospheric convection, rolls are also known to form under specific conditions, with horizontal scales roughly proportional to the boundary layer height. Here we explore within idealized large-eddy simulations, how the scale of convection is modified, when precipitation sets in and intensifies in the course of diurnal solar heating. Before onset of precipitation, Bénard cells with relatively constant diameter form, roughly on the scale of the atmospheric boundary layer. We find that the onset of precipitation then signals an approximately linear (in time) increase in horizontal scale. This scale increase progresses at a speed which is rather insensitive to changes in surface temperature or changes in the rate at which boundary conditions change, hinting at spatial characteristics, rather than temperature, as a possible control on spatial scales of convection. When exploring the depth of spatial correlations, we find that precipitation onset causes a sudden disruption of order and a subsequent complete disintegration of organization —until precipitation eventually ceases. Returning to the initial question of convective

A review on biomass as a fuel for boilers

Energy Technology Data Exchange (ETDEWEB)

Saidur, R.; Abelaziz, E.A.; Demirbas, A.; Hossain, M.S.; Mekhilef, S. [University of Malaya, Kuala Lumpur (Malaysia). Dept. of Mechanical Engineering

2011-06-15

Currently, fossil fuels such as oil, coal and natural gas represent the prime energy sources in the world. However, it is anticipated that these sources of energy will deplete within the next 40-50 years. Moreover, the expected environmental damages such as the global warming, acid rain and urban smog due to the production of emissions from these sources have tempted the world to try to reduce carbon emissions by 80% and shift towards utilizing a variety of renewable energy resources (RES) which are less environmentally harmful such as solar, wind, biomass etc. in a sustainable way. Biomass is one of the earliest sources of energy with very specific properties. In this review, several aspects which are associated with burning biomass in boilers have been investigated such as composition of biomass, estimating the higher heating value of biomass, comparison between biomass and other fuels, combustion of biomass, co-firing of biomass and coal, impacts of biomass, economic and social analysis of biomass, transportation of biomass, densification of biomass, problems of biomass and future of biomass. It has been found that utilizing biomass in boilers offers many economical, social and environmental benefits such as financial net saving, conservation of fossil fuel resources, job opportunities creation and CO{sub 2} and NO emissions reduction. However, care should be taken to other environmental impacts of biomass such as land and water resources, soil erosion, loss of biodiversity and deforestation. Fouling, marketing, low heating value, storage and collections and handling are all associated problems when burning biomass in boilers. The future of biomass in boilers depends upon the development of the markets for fossil fuels and on policy decisions regarding the biomass market.

A Co-Powered Biomass and Concentrated Solar Power Rankine Cycle Concept for Small Size Combined Heat and Power Generation

Directory of Open Access Journals (Sweden)

Eileen Tortora

2013-03-01

Full Text Available The present work investigates the matching of an advanced small scale Combined Heat and Power (CHP Rankine cycle plant with end-user thermal and electric load. The power plant consists of a concentrated solar power field co-powered by a biomass furnace to produce steam in a Rankine cycle, with a CHP configuration. A hotel was selected as the end user due to its high thermal to electric consumption ratio. The power plant design and its operation were modelled and investigated by adopting transient simulations with an hourly distribution. The study of the load matching of the proposed renewable power technology and the final user has been carried out by comparing two different load tracking scenarios, i.e., the thermal and the electric demands. As a result, the power output follows fairly well the given load curves, supplying, on a selected winter day, about 50 GJ/d of thermal energy and the 6 GJ/d of electric energy, with reduced energy dumps when matching the load.

Scaling of divertor heat flux profile widths in DIII-D

International Nuclear Information System (INIS)

Lasnier, C.J.; Makowski, M.A.; Boedo, J.A.; Allen, S.L.; Brooks, N.H.; Hill, D.N.; Leonard, A.W.; Watkins, J.G.; West, W.P.

2011-01-01

New scalings of the dependence of divertor heat flux peak and profile width, important parameters for the design of future large tokamaks, have been obtained from recent DIII-D experiments. We find the peak heat flux depends linearly on input power, decreases linearly with increasing density, and increases linearly with plasma current. The profile width has a weak dependence on input power, is independent of density up to the onset of detachment, and is inversely proportional to the plasma current. We compare these results with previously published scalings, and present mathematical expressions incorporating these results.

Model Research of Gas Emissions From Lignite and Biomass Co-Combustion in a Large Scale CFB Boiler

Directory of Open Access Journals (Sweden)

Krzywański Jarosław

2014-06-01

Full Text Available The paper is focused on the idea of a combustion modelling of a large-scale circulating fluidised bed boiler (CFB during coal and biomass co-combustion. Numerical computation results for three solid biomass fuels co-combustion with lignite are presented in the paper. The results of the calculation showed that in previously established kinetics equations for coal combustion, some reactions had to be modified as the combustion conditions changed with the fuel blend composition. Obtained CO2, CO, SO2 and NOx emissions are located in borders of ± 20% in the relationship to the experimental data. Experimental data was obtained for forest biomass, sunflower husk, willow and lignite cocombustion tests carried out on the atmospheric 261 MWe COMPACT CFB boiler operated in PGE Turow Power Station in Poland. The energy fraction of biomass in fuel blend was: 7%wt, 10%wt and 15%wt. The measured emissions of CO, SO2 and NOx (i.e. NO + NO2 were also shown in the paper. For all types of biomass added to the fuel blends the emission of the gaseous pollutants was lower than that for coal combustion.

Multi-scale sustainability assessments for biomass-based and coal-based fuels in China.

Science.gov (United States)

Man, Yi; Xiao, Honghua; Cai, Wei; Yang, Siyu

2017-12-01

Transportation liquid fuels production is heavily depend on oil. In recent years, developing biomass based and coal based fuels are regarded as promising alternatives for non-petroleum based fuels in China. With the rapid growth of constructing and planning b biomass based and coal based fuels production projects, sustainability assessments are needed to simultaneously consider the resource, the economic, and the environmental factors. This paper performs multi-scale analyses on the biomass based and coal based fuels in China. The production cost, life cycle cost, and ecological life cycle cost (ELCC) of these synfuels are investigated to compare their pros to cons and reveal the sustainability. The results show that BTL fuels has high production cost. It lacks of economic attractiveness. However, insignificant resource cost and environmental cost lead to a substantially lower ELCC, which may indicate better ecological sustainability. CTL fuels, on the contrary, is lower in production cost and reliable for economic benefit. But its coal consumption and pollutant emissions are both serious, leading to overwhelming resource cost and environmental cost. A shifting from petroleum to CTL fuels could double the ELCC, posing great threat to the sustainability of the entire fuels industry. Copyright © 2017 Elsevier B.V. All rights reserved.

Biomass Feedstock National User Facility

Data.gov (United States)

Federal Laboratory Consortium — Bioenergy research at the Biomass Feedstock National User Facility (BFNUF) is focused on creating commodity-scale feed-stocks from native biomass that meet the needs...

A hybrid optimization model of biomass trigeneration system combined with pit thermal energy storage

International Nuclear Information System (INIS)

Dominković, D.F.; Ćosić, B.; Bačelić Medić, Z.; Duić, N.

2015-01-01

Highlights: • Hybrid optimization model of biomass trigeneration system with PTES is developed. • Influence of premium feed-in tariffs on trigeneration systems is assessed. • Influence of total system efficiency on biomass trigeneration system with PTES is assessed. • Influence of energy savings on project economy is assessed. - Abstract: This paper provides a solution for managing excess heat production in trigeneration and thus, increases the power plant yearly efficiency. An optimization model for combining biomass trigeneration energy system and pit thermal energy storage has been developed. Furthermore, double piping district heating and cooling network in the residential area without industry consumers was assumed, thus allowing simultaneous flow of the heating and cooling energy. As a consequence, the model is easy to adopt in different regions. Degree-hour method was used for calculation of hourly heating and cooling energy demand. The system covers all the yearly heating and cooling energy needs, while it is assumed that all the electricity can be transferred to the grid due to its renewable origin. The system was modeled in Matlab© on hourly basis and hybrid optimization model was used to maximize the net present value (NPV), which was the objective function of the optimization. Economic figures become favorable if the economy-of-scale of both power plant and pit thermal energy storage can be utilized. The results show that the pit thermal energy storage was an excellent option for storing energy and shaving peaks in energy demand. Finally, possible switch from feed-in tariffs to feed-in premiums was assessed and possible subsidy savings have been calculated. The savings are potentially large and can be used for supporting other renewable energy projects

ADVANCED BIOMASS REBURNING FOR HIGH EFFICIENCY NOx CONTROL AND BIOMASS REBURNING - MODELING/ENGINEERING STUDIES JOINT FINAL REPORT

Energy Technology Data Exchange (ETDEWEB)

Vladimir M. Zamansky; Mark S. Sheldon; Vitali V. Lissianski; Peter M. Maly; David K. Moyeda; Antonio Marquez; W. Randall Seeker

2000-10-01

This report presents results of studies under a Phase II SBIR program funded by the U. S. Department of Agriculture, and a closely coordinated project sponsored by the DOE National Energy Technology Laboratory (NETL, formerly FETC). The overall Phase II objective of the SBIR project is to experimentally optimize the biomass reburning technologies and conduct engineering design studies needed for process demonstration at full scale. The DOE project addresses supporting issues for the process design including modeling activities, economic studies of biomass handling, and experimental evaluation of slagging and fouling. The performance of biomass has been examined in a 300 kW (1 x 10{sup 6} Btu/hr) Boiler Simulator Facility under different experimental conditions. Fuels under investigation include furniture waste, willow wood and walnut shells. Tests showed that furniture pellets and walnut shells provided similar NO{sub x} control as that of natural gas in basic reburning at low heat inputs. Maximum NO{sub x} reduction achieved with walnut shell and furniture pellets was 65% and 58% respectively. Willow wood provided a maximum NO{sub x} reduction of 50% and was no better than natural gas at any condition tested. The efficiency of biomass increases when N-agent is injected into reburning and/or burnout zones, or along with OFA (Advanced Reburning). Co-injection of Na{sub 2}CO{sub 3} with N-agent further increases efficiency of NO{sub x} reduction. Maximum NO{sub x} reduction achieved with furniture pellets and willow wood in Advanced Reburning was 83% and 78% respectively. All combustion experiments of the Phase II project have been completed. All objectives of the experimental tasks were successfully met. The kinetic model of biomass reburning has been developed. Model agrees with experimental data for a wide range of initial conditions and thus correctly represents main features of the reburning process. Modeling suggests that the most important factors that provide

Small-scale heat detection using catalytic microengines irradiated by laser

Science.gov (United States)

Liu, Zhaoqian; Li, Jinxing; Wang, Jiao; Huang, Gaoshan; Liu, Ran; Mei, Yongfeng

2013-01-01

We demonstrate a novel approach to modulating the motion speed of catalytic microtubular engines via laser irradiation/heating with regard to small-scale heat detection. Laser irradiation on the engines leads to a thermal heating effect and thus enhances the engine speed. During a laser on/off period, the motion behaviour of a microengine can be repeatable and reversible, demonstrating a regulation of motion speeds triggered by laser illumination. Also, the engine velocity exhibits a linear dependence on laser power in various fuel concentrations, which implies an application potential as local heat sensors. Our work may hold great promise in applications such as lab on a chip, micro/nano factories, and environmental detection.We demonstrate a novel approach to modulating the motion speed of catalytic microtubular engines via laser irradiation/heating with regard to small-scale heat detection. Laser irradiation on the engines leads to a thermal heating effect and thus enhances the engine speed. During a laser on/off period, the motion behaviour of a microengine can be repeatable and reversible, demonstrating a regulation of motion speeds triggered by laser illumination. Also, the engine velocity exhibits a linear dependence on laser power in various fuel concentrations, which implies an application potential as local heat sensors. Our work may hold great promise in applications such as lab on a chip, micro/nano factories, and environmental detection. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32494f

Solid biomass barometer - EurObserv'ER - December 2016

International Nuclear Information System (INIS)

2016-12-01

Solid biomass consumption, primarily wood energy, is still largely governed by heating requirements which are climate-dependent. The main factor for the European rebound in solid biomass consumption as primary energy during the winter of 2015 is that it was not as mild across the continent as the previous winter. Leaving aside climatic variations, the use of solid biomass for producing heat or electricity has tended to increase in the European Union, spurred on by European support policies. A new consumption record of 93.8 Mtoe was posted in 2015... a rise of 3.8 Mtoe over 2014

Advanced Biomass Gasification Projects

Energy Technology Data Exchange (ETDEWEB)

1997-08-01

DOE has a major initiative under way to demonstrate two high-efficiency gasification systems for converting biomass into electricity. As this fact sheet explains, the Biomass Power Program is cost-sharing two scale-up projects with industry in Hawaii and Vermont that, if successful, will provide substantial market pull for U.S. biomass technologies, and provide a significant market edge over competing foreign technologies.

Dynamic Modeling and Validation of a Biomass Hydrothermal Pretreatment Process - A Demonstration Scale Study

DEFF Research Database (Denmark)

Prunescu, Remus Mihail; Blanke, Mogens; Jakobsen, Jon Geest

2015-01-01

for the enzymatic hydrolysis process. Several by-products are also formed, which disturb and act as inhibitors downstream. The objective of this study is to formulate and validate a large scale hydrothermal pretreatment dynamic model based on mass and energy balances, together with a complex conversion mechanism......Hydrothermal pretreatment of lignocellulosic biomass is a cost effective technology for second generation biorefineries. The process occurs in large horizontal and pressurized thermal reactors where the biomatrix is opened under the action of steam pressure and temperature to expose cellulose...... and kinetics. The study includes a comprehensive sensitivity and uncertainty analysis, with parameter estimation from real-data in the 178-185° range. To highlight the application utility of the model, a state estimator for biomass composition is developed. The predictions capture well the dynamic trends...

Spatially-explicit modeling of multi-scale drivers of aboveground forest biomass and water yield in watersheds of the Southeastern United States.

Science.gov (United States)

Ajaz Ahmed, Mukhtar Ahmed; Abd-Elrahman, Amr; Escobedo, Francisco J; Cropper, Wendell P; Martin, Timothy A; Timilsina, Nilesh

2017-09-01

Understanding ecosystem processes and the influence of regional scale drivers can provide useful information for managing forest ecosystems. Examining more local scale drivers of forest biomass and water yield can also provide insights for identifying and better understanding the effects of climate change and management on forests. We used diverse multi-scale datasets, functional models and Geographically Weighted Regression (GWR) to model ecosystem processes at the watershed scale and to interpret the influence of ecological drivers across the Southeastern United States (SE US). Aboveground forest biomass (AGB) was determined from available geospatial datasets and water yield was estimated using the Water Supply and Stress Index (WaSSI) model at the watershed level. Our geostatistical model examined the spatial variation in these relationships between ecosystem processes, climate, biophysical, and forest management variables at the watershed level across the SE US. Ecological and management drivers at the watershed level were analyzed locally to identify whether drivers contribute positively or negatively to aboveground forest biomass and water yield ecosystem processes and thus identifying potential synergies and tradeoffs across the SE US region. Although AGB and water yield drivers varied geographically across the study area, they were generally significantly influenced by climate (rainfall and temperature), land-cover factor1 (Water and barren), land-cover factor2 (wetland and forest), organic matter content high, rock depth, available water content, stand age, elevation, and LAI drivers. These drivers were positively or negatively associated with biomass or water yield which significantly contributes to ecosystem interactions or tradeoff/synergies. Our study introduced a spatially-explicit modelling framework to analyze the effect of ecosystem drivers on forest ecosystem structure, function and provision of services. This integrated model approach facilitates

Study of the potential valorisation of heavy metal contaminated biomass via phytoremediation by fast pyrolysis: Part I. Influence of temperature, biomass species and solid heat carrier on the behaviour of heavy metals

Energy Technology Data Exchange (ETDEWEB)

C. Lievens; J. Yperman; J. Vangronsveld; R. Carleer [Hasselt University, Diepenbeek (Belgium). Laboratory of Applied Chemistry

2008-08-15

Presently, little or no information of implementing fast pyrolysis for looking into the potential valorisation of heavy metal contaminated biomass is available. Fast pyrolysis of heavy metal contaminated biomass (birch and sunflower), containing high amounts of Cd, Cu, Pb and Zn, resulting from phytoremediation, is investigated. The effect of the pyrolysis temperature (623, 673, 773 and 873 K) and the type of solid heat carrier (sand and fumed silica) on the distribution of the heavy metals in birch and sunflower pyrolysis fractions are studied. The goal of the set-up is 'concentrating' heavy metals in the ash/char fraction after thermal treatment, preventing them to be released in the condensable and/or volatile fractions. The knowledge of the behaviour of heavy metals affects directly future applications and valorisation of the pyrolysis products and thus contaminated biomass. They are indispensable for making and selecting the proper thermal conditions for their maximum recovery. In view of the future valorisation of these biomasses, the amounts of the pyrolysis fractions and the calorific values of the obtained liquid pyrolysis products, as a function of the pyrolysis temperature, are determined. 46 refs., 8 figs., 4 tabs.