Development and application of BioFeed model for optimization of herbaceous biomass feedstock production

An efficient and sustainable biomass feedstock production system is critical for the success of the biomass based energy sector. An integrated systems analysis framework to coordinate various feedstock production related activities is, therefore, highly desirable. This article presents research conducted towards the creation of such a framework. A breadth level mixed integer linear programming model, named BioFeed, is proposed that simulates different feedstock production operations such as harvesting, packing, storage, handling and transportation, with the objective of determining the optimal system level configuration on a regional basis. The decision variables include the design/planning as well as management level decisions. The model was applied to a case study of switchgrass production as an energy crop in southern Illinois. The results illustrated that the total cost varied between 45 and 49 $ Mg⁻¹ depending on the collection area and the sustainable biorefinery capacity was about 1.4 Gg d⁻¹. The transportation fleet consisted of 66 trucks and the average utilization of the fleet was 86%. On-farm covered storage of biomass was highly beneficial for the system. Lack of on-farm open storage and centralized storage reduced the system profit by 17% and 5%, respectively. Increase in the fraction of larger farms within the system reduced the cost and increased the biorefinery capacity, suggesting that co-operative farming is beneficial. The optimization of the harvesting schedule led to 30% increase in the total profit. Sensitivity analysis showed that the reduction in truck idling time as well as increase in baling throughput and output density significantly increased the profit.     

Integrated biomass energy systems and emissions of carbon dioxide

Electric Power Research Institute (EPRI) and the US Department of Energy (DOE) have been funding a number of case studies under the initiative entitled “Economic Development through Biomass Systems Integration”, with the objective of investigate the feasibility of integrated biomass energy systems, utilizing a dedicated feedstock supply system (DFSS) for energy production. This paper deals with the full fuel cycle for four of these case studies, which have been examined with regard to the emissions of carbon dioxide, CO₂. Although the conversion of biomass to electricity in itself does not emit more CO₂ than is captured by the biomass through photosynthesis, there will be some CO₂ emissions from the DFSS. External energy is required for the production and transportation of the biomass feedstock, and this energy is mainly based on fossil fuels. By using this input energy, CO₂ and other greenhouse gases are emitted. However, by utilizing biomass with fossil fuels as external input fuels, we would get about 10–15 times more electric energy per unit fossil fuel, compared with a 100% coal power system. By introducing a DFSS on former farmland the amount of energy spent for production of crops can be reduced, the amount of fertilizers can be decreased, the soil can be improved and a significant amount of energy will be produced compared with an ordinary farm crop. Compared with traditional coal-based electricity production, the CO₂ emissions are in most cases reduced significantly by as much as 95%. The important conclusion is the great potential for reducing greenhouse gas emissions through the offset of coal by biomass.     

The role of biomass in California's hydrogen economy

This paper presents the results of a model of hydrogen production from waste biomass in California. We develop a profit-maximizing model of a biomass hydrogen industry from field to vehicle tank. This model is used to estimate the economic potential for hydrogen production from two waste biomass resources in Northern California—wheat straw and rice straw—taking into account the on the ground geographic dimensions of both biomass supply and hydrogen demand. The systems analysis approach allows for explicit consideration of the interactions between feedstock collection, hydrogen production, and hydrogen distribution in finding the optimal system design. This case study approach provides insight into both the real-world potential and the real-world cost of producing hydrogen from waste biomass. Additional context is provided through the estimation of California's total waste biomass hydrogen potential. We find that enough biomass is available from waste sources to provide up to 40% of the current California passenger car fuel demand as hydrogen. Optimized supply chains result in delivered hydrogen costing between $3/kg and $5.50/kg with one-tenth of the well-to-wheels greenhouse gas emissions of conventional gasoline-fueled vehicles.     

A feedstock supply model integrating the official organization for China's biomass generation plants

Shortage of feedstock has hindered the development of China's biomass power generation because it is highly difficult to collect straw in China. We pioneered a new feedstock supply model in which the formal official organization of villagers' committees is introduced. Different from the previous feedstock supply patterns, the immaterial utility of relative stakeholders and the impact of villagers' committees on farmers' behavior are considered in this paper. To compare this pattern's performance with that of the conventional ones, this paper developed a multi-agent model specifically for China's situation. We applied the model to simulate the operation of a biomass supply chain. The results show that the proposed feedstock supply pattern can significantly increase the profits of biomass plants, biomass supply amounts, and farmers' participation, and in contrast with the broker pattern, it can lower feedstock prices through disintermediation. Sensitivity analyses show that preferential feed-in tariffs are still necessary for biomass power and that the new pattern can ease the government's subsidy burdens. Additionally, farmers' opportunity costs for supplying biomass, their perceptions of immaterial utility and the cooperative's financial resource schemes of the public welfare fund all have differing impacts on the achievement of the new pattern.     

The primary forest fuel supply chain: A literature review

This paper provides a literature review of articles on the primary forest fuel supply chain which have been published in English speaking peer-reviewed journals from 1989 to 2011. The focus is on the key issues of the transportation of primary forest fuel to heat and/or power plants: (i) transportation modes, (ii) terminal types, and (iii) forest fuel supply chain management, and provides basics on the logistically relevant characteristics of wood as feedstock such as on various feedstock assortments.The analysed supply chains include the transshipment, storage, handling (e.g. chipping) and transportation of primary forest fuel from the place of harvest to energy conversion plant. Due to spatial distribution, low mass density, low energy density and low bulk density, the transportation of primary forest fuel is crucial for economic efficiency as well as for reduced CO₂ emissions. As a consequence of forests accessibility, road transportation (after hauling the biomass to the forest road) is the first step of the modern primary forest fuel supply chain. For longer transportation distances, rail or waterway is preferred because of lower transportation costs per volume transported and lower CO₂ emissions. We highlight that some experience exists in multimodal transport, including truck, train or ship. Intermodal transport, however, has not been studied in the past and, therefore, an outlook for the research requirements is made here.     

Supply chain optimization of residual forestry biomass for bioenergy production: The case study of Portugal

Within a large set of renewable energies being explored to tackle energy sourcing problems, bioenergy can represent an attractive solution if effectively managed. The supply chain design supported by mathematical programming can be used as a decision support tool to the successful bioenergy production systems establishment. This strategic decision problem is addressed in this paper where we intent to study the design of the residual forestry biomass to bioelectricity production in the Portuguese context. In order to contribute to attain better solutions a mixed integer linear programming (MILP) model is developed and applied in order to optimize the design and planning of the bioenergy supply chain. While minimizing the total supply chain cost the production energy facilities capacity and location are defined. The model also includes the optimal selection of biomass amounts and sources, the transportation modes selection, and links that must be established for biomass transportation and products delivers to markets. Results illustrate the positive contribution of the mathematical programming approach to achieve viable economic solutions. Sensitivity analysis on the most uncertain parameters was performed: biomass availability, transportation costs, fixed operating costs and investment costs.     

Optimization-based planning of a biomass to hydrogen (B2H2) system using dedicated energy crops and waste biomass

The utilization of biomass for hydrogen production is one of the promising options for a sustainable energy system. In this paper, we develop a new optimization-based approach for design and analysis of the B2H2 system including production, storage, and distribution using dedicated energy crops as well as various resources of waste biomass. To achieve this goal, we first develop an optimization model using mixed-integer linear programming technique that includes practical variables and constraints for decision-making about the usage of dedicated energy crops. We then conduct a case study of the B2H2 system for the road transportation sector of future Korea. As a result, we identify an optimal system configuration that includes the utilized biomass types, occupied land sizes, the number and location of facilities, and the biomass and hydrogen flows between regions. We also analyze the cost distributions and the sensitivity of the main cost drivers on the total annual cost (TAC). The results reveal that the proposed B2H2 system is economically competitive with some of the other renewable-based hydrogen supply systems (wind and solar) in Korea.     

Modeling the energy potential of biomass – H2RES

Modeling biomass as a renewable energy source poses many challenges with respect to feedstock variability, which are difficult to account for. It is found that at the preliminary stages of energy planning, heating value and moisture content of the feedstock are the most important factors. In addition, the effects of harvesting, transportation and storage are found to be significant even though they are often overlooked. Using the gathered information a biomass module for energy planning is created and integrated to H₂RES, a renewable energy planning program. Using this excel based software, a case study for a wood processing factory is performed, using the waste wood as feedstock. Comparing various scenarios, it is concluded that using a combination of solid oxide fuel cells, solar panels and steam turbines can satisfy the factories energy requirements with excess sold to the grid.     

Supply of biomass, bioenergy, and carbon mitigation: Method and application

This study develops an analytical framework for deriving the supply of biomass feedstock and subsequently electricity and CO₂ displacement generated from the biomass. This systematic approach minimizes the total cost of both feedstock and electricity production and involves the determination of the optimal power plant size and the derivation of the supply curves. The analytical framework is applied to the case of logging residues in the US. Both the theoretical and empirical results point to the importance of simultaneously considering feedstock production, energy conversion, and environmental benefits/costs in bioenergy project development, leading to useful policy implications for bioenergy development and deployment.     

Development of a biorefinery optimized biofuel supply curve for the Western United States

A resource assessment and biorefinery siting optimization model was developed and implemented to assess potential biofuel supply across the Western United States from agricultural, forest, urban, and energy crop biomass. Spatial information including feedstock resources, existing and potential refinery locations and a transportation network model is provided to a mixed integer-linear optimization model that determines the optimal locations, technology types and sizes of biorefineries to satisfy a maximum profit objective function applied across the biofuel supply and demand chain from site of feedstock production to the product fuel terminal. The resource basis includes preliminary considerations of crop and residue sustainability. Sensitivity analyses explore possible effects of policy and technology changes. At a target market price of 19.6 $ GJ^?1, the model predicts a feasible production level of 610–1098 PJ, enough to supply up to 15% of current regional liquid transportation fuel demand.     

A GIS-based method for identifying the optimal location for a facility to convert forest biomass to biofuel

There is growing interest in the production of biofuels from woody biomass. Critical to the financial success of producing biofuel is identifying the optimal location for the facility. The location decision is especially important for woody biomass feedstock owing to the distributed nature of biomass and the significant costs associated with transportation. This study introduces a two-stage methodology to identify the best location for biofuel production based on multiple attributes. Stage I uses a Geographic Information System approach to identify feasible biofuel facility locations. The approach employs county boundaries, a county-based pulpwood distribution, a population census, city and village distributions, and railroad and state/federal road transportation networks. In Stage II, the preferred location is selected using a total transportation cost model. The methodology is applied to the Upper Peninsula of Michigan to locate a biofuel production facility. Through the application of the two-stage methodology, the best possible location for biofuel production was identified as the Village of L’anse in Baraga County. Also investigated are the sensitivity of transportation cost and the optimal site for biofuel production to changes in several key variables. These additional variables included fuel price, transportation distance, and pulpwood availability. By applying sensitivity analysis based on limited availability of feedstock, the City of Ishpeming emerged as another viable location for the production facility.     

Economic analysis of alternative logistics systems for Tennessee-produced switchgrass to penetrate energy markets

Growing biomass crops for energy production on low productivity lands not used for food production has been suggested as an alternative to reduce dependence on fossil fuels and to mitigate greenhouse gas emissions from transportation fuel. Switchgrass is considered a potential feedstock in various states, including Tennessee, given its high biomass content in a wide range of environments. However, its low density relative to energy value and resulting high logistics costs impede the profitability of switchgrass-based bioenergy. The objective of this study is to determine the optimal logistics configuration for a collection/distribution hub to market Tennessee-produced switchgrass for bioenergy production. A mathematical programming model integrated with a geographic information system is used to maximize the net present value of profit from a hub that serves switchgrass producers and bioenergy markets. Six logistics configurations delivering switchgrass to local or international bioenergy markets are evaluated. The results highlight the economic challenges of penetrating energy markets for a switchgrass collection/distribution hub – only one logistics configuration that targets the local market is profitable. However, serving local and international markets becomes more feasible as investment risk declines. The results imply that a clear direction for national bioenergy policy is crucial to developing a biomass feedstock for the U.S. bioenergy industry.     

A Life Cycle Analysis on a Bio-DME production system considering the species of biomass feedstock in Japan and Papua New Guinea

This paper describes the performance and/or CO₂ intensities of a Bio-DME (Biomass Di-methyl Ether) production system, considering the differences of biomass feedstock. In the past LCA studies on an energy chain model, there is little knowledge on the differences of biomass feedstock and/or available condition. Thus, in this paper, we selected Papua New Guinea (PNG) which has good potential for supply of an energy crop (a short rotation forestry), and Japan where wood remnants are available, as model areas. Also, we referred to 9 species of biomass feedstock of PNG, and to 8 species in Japan.The system boundary on our LCA consists of (1) the pre-treatment process, (2) the energy conversion process, and (3) the fuel transportation process. Especially, since the pre-treatment process has uncertainties related to the moisture content of biomass feedstock, as well as the distance from the cultivation site to the energy plant, we considered them by the Monte Carlo simulation.Next, we executed the process design of the Bio-DME production system based on the basic experimental results of pyrolysis and char gasification reactions. Due to these experiments, the gas components of pyrolysis and the gasification rate under H₂O (steam) and CO₂ were obtained. Also, we designed the pressurized fluid-bed gasification process. In a liquefaction process, that is, a synthesis process of DME, the result based on an equilibrium constant was used. In the proposed system, a steam turbine for an auxiliary power was assumed to be equipped, too. The energy efficiencies are 39.0–56.8 LHV-%, depending upon the biomass species.Consequently, CO₂ intensities in the whole system were 16.3–47.2 g-CO₂/MJ-DME in the Japan case, and 12.2–36.7 g-CO₂/MJ-DME in the PNG one, respectively.Finally, using the results of CO₂ intensities and energy efficiencies, we obtained the regression equations as parameters of hydrogen content and heating value of a feedstock. These equations will be extremely significant when we install the BTL (biomass-to-liquid, ex. Bio-DME) energy system in the near future, in order to mitigate CO₂ emissions effectively, and to estimate the energy’s efficiency.     

Multi-farm economic analysis of perennial energy crops in Central Greece, taking into account the CAP reform

This study analyses farm level economic impacts of biomass production from perennial crops including Arundo donax L. (arundo), Miscanthus x giganteus (miscanthus), Panicum virgatum L. (switchgrass) and Cynara cardunculus L. (cardoon). Regional biomass supply curves are estimated with a dynamic, multi-farm, mathematical programming model. Micro-economic data for the model are generated from farm surveys covering 52 farms containing a total of 400 parcels, in Central Greece. The study also examines the potential effects of the Common Agricultural Policy reform in 2003 on regional biomass supply. Simulations show that the policy reform toward decoupled subsidies lowers the cost of biomass between 15 and 25 euro per tonne. Switchgrass appears to be the most attractive option, followed by cardoon and miscanthus. Due to high specific machinery cost, arundo is never preferred. Relative to the agricultural policy setting of Agenda 2000, the biomass potential increases more for farms of small economic size and farms with a higher share of cotton.     

生物质能转化技术及资源综合开发利用研究

开发利用生物质能源,对保障国家能源安全、实现节能减排战略目标意义重大。我国生物质能的开发利用技术取得了许多优秀成果,但与发达国家相比,还存在不少差距。生物质资源可分为林业资源、农业资源、生活污水和工业有机废水、城市固体废物、禽畜粪便等,其化学组成和化学结构也差异很大。生物质能的转化技术方式主要为:直接燃烧方式,物化转换方式,生化转化技术,化学转化方式。面对传统能源的市场竞争,我国生物质能源开发只有依靠科技进步,将生物质能资源进行精细化工产品的深度利用,综合开发,使之增值,反哺生物柴油、燃料乙醇及生物质燃气等能源产品的开发;利用现代转基因技术培育能源植物新品种,提高出油率,降低原料成本;创新生物质能转化技术,提高生物质能产品产量、降低生产成本。运用精细化工技术平台开发生物质资源,已成为生物质资源综合利用领域的研发热点。在生产生物质能源产品的同时,综合开发利用生物质资源,将成为未来世界新的经济增长点。     

Optimal plant size and feedstock supply radius: A modeling approach to minimize bioenergy production costs

Bioenergy production involves a series of interrelated activities associated with feedstock production and feedstock-to-energy conversion. Thus, decisions on bioenergy production and deployment should be based on the simultaneous consideration of the entire supply chain. Based on cost minimization of both feedstock production and energy conversion, we develop a generic framework for determining the optimal bioenergy conversion plant size, the corresponding feedstock supply radius, and bioenergy production costs. The theoretical framework elucidates the relationships among activities along the bioenergy supply chain, suggesting strategies for enhancing the cost competitiveness of bioenergy. Such relationships as well as applications of our theoretical model are further illustrated using cases of producing electricity and cellulosic ethanol from biomass.     

Analysing transport costs of Danish forest wood chip resources by means of continuous cost surfaces

While international markets for woody biomass emerge, growing consumption of wood chips for energy in Denmark is leading to increasing import. With improved competitiveness and unquestionable environmental benefits, domestic wood chip supply is preferable, but measures must be taken to make the supply chain more cost efficient. One of the major contributors to the delivered costs of wood chips is transportation, which is highly determined by the geographical location of forests and energy plants. This paper presents a method based on continuous cost surface mapping using raster-based geographical information systems (GISs). The national wood chip resources have been mapped and for selected bioenergy plants the costs of transporting the annual fuel demand have been modelled using cost distance functions, supply curves and sensitivity analysis. Hence a geographically determined relation of cumulative wood chip resources and their average costs was established. The results may be used for socio-economically sound resource allocation, optimal plant fuel mix, and planning of future energy plants.     

纸业基地循环经济发展模式

介绍某一纸业基地的循环经济发展模式。该纸业基地通过“七个集中”构建了因区的循环经济产业链,具体包括集中供热、集中供电、集中供冷、集中供水、集中治污、集中固废利用、集中物流。该纸业基地通过科学规划,将造纸和发电两大行业实现横向资源整合,提高能源利用率,减少污染物排放。     

Hydrogen production at centralized utilization of agricultural waste

There is a problem of utilization of a large amount of organic waste in the agro-industrial complex. Most of the waste is generated on livestock farms (56%) and crop production (35.6%). Centralized biogas plants are a good solution for efficient processing of agricultural waste and biofuel production. An analysis of the possibilities of cow manure utilizing and dry biomass of amaranth with the subsequent hydrogen production was implemented for Tatarstan Republic. The diagram of five large facilities utilizing waste from 7 to 10 districts included in the region is introduced.The diagram of steam catalytic conversion of biogas is specified. The introduced hydrogen production scheme includes: collection of plant waste and manure of livestock complexes for centralized recycling (the optimal mixture of dry biomass of Amaranthus retroflexus L. leaves and cow manure for organic dry matter is 1:1.5); mixture preparation and ultrasonic treatment at a frequency of 22 kHz and an exposure intensity of 10 W/cm2; anaerobic digestion in the mesophilic mode at a temperature of 310 K, the hydraulic retention time is 12 days; the compressor supplying the resulting biogas into the gasholder for intermediate storage; purification of biogas from carbon dioxide, hydrogen sulfide and other impurities in the scrubber; steam methane reforming: the biomethane is compressed by a compressor to a pressure of 15 atm., then fed to the reformer, heated, mixed with steam in the ratio H2O/CH4 = 2.5 and subjected to conversion at a temperature of 1073 K and a pressure of 1 atm., before exiting, the resulting gas is cooled to 573 K; the catalytic reactor for carrying out a water vapor conversion reaction in which a mixture of carbon monoxide and steam is converted, the products are hydrogen and carbon dioxide; purification of the obtained hydrogen to a purity of 99.99% vol. In the short-cycle adsorption system; hydrogen supply to the consumer. It is possible to utilize of 4.4 million tons of waste annually, and also to produce 107,341 kg/day of hydrogen with a purity of 99.99% by volume.     

生物质气化发电技术

随着人们对能源需求的日益增长，作为人类目前主要能源来源的化石燃料却迅速减少，而生物质能是一种重要的可再生能源，它分布广泛，数量巨大。但由于它能量密度低，又分散，收集和运输困难，所以难以大规模集中处理。另一方面随着经济的发展，我国电力供应日益紧张，对电力需求很大，电价居高不下，在这种环境下，通过气化发电技术，把生物质转化为电力，既能大规模处理生物质废料，又能为生产提供电力，具有明显的社会和经济效益。本文主要讲述生物质的气化技术，生物质气净化处理技术及生物质气用于内燃机的发电技术。