Straw Supply Research Articles

How should one design and position straw feeders in group-housed horses? A case study on occupancy and agonistic interactions at straw feeders in a large group of horses

As group housing of horses can be associated with increased injury risk especially when there are limited resources, the aim of this study was to allow initial, scientifically based recommendations regarding the positioning and design of straw feeders. Data collection took place in a Hinrichs Innovation + Technik (HIT) active stable with 50–62 horses kept in one single group. Occupancy, feeding distances, prevalence of agonistic interactions (AIS) as well as the percentage of feeding disturbances at two different straw feeders were analysed. Equine behaviour was recorded for 6 h/day on 15 summer and 15 winter days. Using generalised linear mixed models, considering the fixed effects of feeder, a fresh straw supply and the interaction of observation day and time period delivered the best prediction for the number of feeding events/h and the prevalence of AIS/h. Here, both feeders differed (p < 0.05) with twice as many feeding events/h, but threefold more AIS/h respectively twice as many AIS/horse at the larger feeder, where conspecifics fed side by side. Sixty-five % of the AIS with low risk of injury and 92 % of the AIS with high risk of injury led to feeding disturbances. The latter made up 25 % of all AIS in total with no differences between both feeders. Feeding distances did not differ either. The horses tended to use only every third opening space when feeding simultaneously. This knowledge should be taken into account when making assumptions about the de facto animal:feeding place ratio and the design of straw feeders in the future. Moreover, regarding the smaller feeder, the horses preferred to feed simultaneously with the feeder edge between them, so that the actual animal distances were smaller. Additional research is needed to investigate, how feeding in rectangular position to each other influences threatening behaviour inside a feeder. In this study, a central positioning within a paddock was beneficial with respect to feeder usage, but disadvantageous regarding AIS and displacements. However, the investigation of further straw feeders and farms is essential to allow general statements, as the study also proves that many factors such as season and rank order stability potentially influence equine behaviour at straw feeders.

Sustainability and circularity assessment of biomass-based energy supply chain

Climate change and other environmental consequences of socio-economic activities require a more sustainable and circular growth. At the same time, the limitation of the earth resource demands industries to improve resource efficiency and increase the rate of recycling of materials. There are several sustainable and circular alternatives that the industries may adopt. However, the question is that among these alternatives, which one should be selected for implementation for the highest sustainable and circular benefits. This study introduces a novel tool for assessing the sustainability and circularity of biomass-based energy supply chains, integrating multi-criteria decision-making methods with life cycle thinking approach. It evaluates five alternatives using a sustainability and circularity indicators, offering new insights into the deloyment of circular business models at companies in biomass-based energy supply chain. The tool is also applied to a specific rice straw supply chain in Italy, to assess the sustainability and circularity of five alternatives and outrank them. The results indicated that not all the alternatives are better in terms of supporting sustainable development and circular economy, compared to the baseline business model. In this supply chain, the extended lifetime for digestate from the aerobic digestion plant is the most ‘sustainable and circular’ alternative, while the capture of carbon dioxide from the same plant and its use for microalgae cultivation is the least ‘sustainable and circular’ alternative. A sensitivity analysis was conducted on different weighting sets during the assessment. It indicated that the priority of the decision makers can slightly change the outrank of the alternatives and the magnitude of the outranks.

Optimization of straw supply chain considering carbon emissions, supply uncertainty and facility disruption risk

Optimization of straw supply chain considering carbon emissions, supply uncertainty and facility disruption risk

The Costs of Straw in Germany: Development of Regional Straw Supply Costs between 2010 and 2020

BackgroundThe bioeconomy relies strongly on the availability of biomass, including biogenic waste, residues and by-products. The cost of supply often represents a significant proportion of the total value of the resource. However, there is limited insight into the current supply costs of wastes, residues and by-products. This includes straw, which is the most important agricultural by-product in Germany. Despite its importance, standardised information on supply costs or market prices, as well as their temporal and spatial variation, is missing.AimTherefore, there is an urgent need for the temporal and spatial monitoring of individual cost components within total supply costs. This is essential to identify the most cost-effective options for the utilisation of agricultural by-products. Therefore, this study focuses on the case of straw to develop a model capable of visualising and mapping regional supply costs over time.MethodWe use an activity-based costing approach to calculate and monitor regional supply costs, defined as the monetary expenditure required to make straw available at the farm level. Our methodology combines typical technical and operational aspects of straw collection and transport with regional wage statistics, yield data, farm sizes, fuel prices and labour costs. We also consider storage costs and opportunity costs associated with nutrient replacement and conduct sensitivity analyses to measure their impact. To validate our calculations, we compare them with actual straw prices. To establish a reliable cost monitoring system, we propose an approach to assess the quality of input data.ResultIn 2011, the regional supply costs for straw varied from 45.72 EUR/Mg[FM] to 92.92 EUR/Mg[FM], showing a wide range. Over the years, the German average supply cost for straw increased from 56.78 EUR/Mg[FM] in 2010 to 58.79 EUR/Mg[FM] in 2020, with a peak of 61.24 EUR/Mg[FM] in 2018. This suggests that the temporal impact on mass-specific costs is relatively moderate compared to the spatial distribution of supply costs. The sensitivity analysis highlights storage time and costs, straw yield and wage levels as the main drivers of supply costs. Doubling the storage period from 3 to 6 months increases total costs by 20%. On average, the costs explain 75% of the straw price across all federal states, depending on annual price and cost levels. The quality assessment of input data shows that currently 68% of the data cannot be automatically extracted for continuous monitoring. Detailed results are available in a corresponding data publication: https://doi.org/10.5281/zenodo.8145082.ConclusionIn the absence of standardised market prices, the model presented provides an approach to estimating the supply costs of straw, expressed in terms of the monetary cost to farmers of mobilising straw. This cost information could be a valid database for further techno-economic assessments or models to evaluate the economic feasibility of straw valorisation. Due to the modular structure of the model, the future development of supply costs can be considered if the input data are adapted to future scenarios.Graphical

Bioenergy feedstock supply from wheat straw: A farm level model incorporating trade‐offs in crop choices, disease risk, and soil fertility

AbstractSecond‐generation biofuel (e.g., ethanol, renewable diesel) can be made from crop residues. However, the availability of residues for biofuel production is uncertain, because farmers have the option to grow different crops and use the residues for alternative purposes, such as livestock bedding and feed, or leave them in the field to improve soil quality. Taking Canadian wheat straw supply as an example, we develop a dynamic programming model to investigate a farmer's wheat straw supply decision in response to different wheat straw and grain prices. Our model considers crop choices between wheat and canola in the context of disease risk, the trade‐off between the immediate payoffs a farmer may receive from bailing and selling wheat straw, and the long‐term adverse effects that removing wheat straw from the soil surface may have on wheat and canola yields. The results from this study provide insights into how farm‐level supply decisions, in response to wheat straw price changes, affect soil quality dynamics and scale up to regional wheat straw supply for biofuel production. This information also has implications for land use change and the sustainability of feedstock supply for biofuels.

Analysis of carbon emissions for district heating using biomass straw instead of coal: A case study

ABSTRACT Decarbonizing district heating requires utilization of low-emitting energy sources. However, earlier studies did not fully consider the district heating potential and CO2 reduction impacts of limited biomass sources. This study presents a new model that examines the potential for utilizing biomass straw sources as fuel for biomass boilers and thermal power plants, with a case study conducted in Heilongjiang Province, China. Results from the model show that the available biomass straw supply increases from 83,799 kilotons to approximately 127,939 kilotons before declining to around 90,000 kilotons. By employing biomass straw as fuel for district heating, an area between 99.4 and 469.8 million m2 can be served by biomass boilers and thermal power plants, leading to CO2 emission reductions ranging from 15.21 to 30.41 million tons. This reduction represents 19–38% compared to the initial CO2 emissions, indicating potential positive carbon reduction benefits. The developed model can be useful for policy makers and industry stakeholders seeking efficient strategies for decarbonizing district heating.

Ammonia tolerance and microbial community in thermophilic co-digestion of sewage sludge initiated with lignocellulosic biomass

Rice straw is a useful lignocellulosic biomass for controlling ammonia inhibition in the thermophilic anaerobic digestion of sewage sludge. However, it is challenging to procure rice straw throughout the year because of its seasonal production. This study investigated methane production in a laboratory-scale digester by gradually decreasing rice straw addition to solid thermophilic sewage sludge digestion. The decrease in rice straw did not accumulate volatile fatty acids and stabilized methane production. Even with increased sludge concentration without rice straw, methane production continued under high ammonia conditions. Ammonia tolerance of the digested sludge of the experimental digester was higher than that of conventionally digested sludge. The cellulose-degrading bacteria Clostridia and high ammonia-resistant archaea Methanosarcina were dominant in the experimentally digested sludge. The community was maintained for over 200 days after discontinuing the rice straw supply. These findings suggest that anaerobic digestion initiation with rice straw is appropriate to facilitate ammonia-tolerant communities.

Cooperation between specialized cropping and livestock farms at local level reduces carbon footprint of agricultural system: A case study of recoupling maize-cow system in South China

Decoupling of crop and livestock production has become increasingly common in the world during to past decades. The cooperation between specialized crop and livestock farms have been paid more attention for the development of sustainable agriculture. This study assumed that rebuilding the linkage between specialized crop and livestock farms through cooperation at the local level would decrease agricultural GHG emissions. Therefore, we designed a cooperative crop-livestock farming model (CCLS) in South China by recoupling the cow farm with the sweet maize cultivation farms around it to demonstrate the hypothesis based on carbon footprint (CF) method. The CFs under two cooperative scenarios (CCLS20 and CCLS50) were compared with the corresponding decoupling models (DCLS20 and DCLS50). Results showed that CCLS significantly reduced GHG emissions from cropping systems in comparison to DCLS primarily by increasing the soil organic carbon storage while decreasing accumulative N2O emissions. In specific, the CFs of CCLS20 and CCLS50 were 48.78% and 623.34% lower than DCLS20 and DCLS50, respectively. The yield-based CFs of CCLS20 and CCLS50 were 66.30% and 165.99% lower than DCLS20 and DCLS50, respectively. Meanwhile, the CF of the cow farm in CCLS20 and CCLS50 were 8.80% and 8.22% lower than that in DCLS20/50 by lowering relative GHG emissions of straw supply in roughage forage and shortening manure storage time in the manure management process. Finally, the yield-based CF in CCLS20 and CCLS50 were 67.68% and 168.51% lower than the DCLS20 and DCLS50, respectively, demonstrating that the cooperation between specialized planting and livestock farms at local level reduced the CF of the agricultural production chain by the synergistic reduction effects of GHG emissions in cropland, livestock rearing and transportation processes. The results would provide a quantitative understanding of the net GHG emission of cooperative crop-livestock system at the local level in China and valuable information for the development of sustainable farming system in the world.

Challenges of adopting the principles of circular economy in sparsely populated areas: Finnish case study on organizing straw supply for cellulose production

This paper examines the possibilities to recycle residue material from farm production. The review is based on a case study on using straw as a raw material for cellulose. The focus is on organizing the logistics related to collecting straw from fields and transporting it to a cellulose processing plant in Finland. When developing the logistics system, the aim is to use existing machinery and infrastructure as much as possible. Farmers oversee the logistics from farm to local depot themselves with the aid of baling service providers. Two options are provided: 1) transport of bales to the cellulose production plant on HCT trucks or 2) pretreatment during which the material is extracted, cutting the transport need between the local depot and the cellulose factory by 70%. The most reasonable option depends on the pretreatment technology used and the distance between local depot and plant.

Novel Methodology to Assess Advanced Biofuel Production at Regional Level: Case Study for Cereal Straw Supply Chains

Nowadays, there is an urgent necessity for breakthrough technologies able to reduce process complexity and to lower costs to make the biomass-based biodiesel supply chain competitive. This paper presents an innovative methodology for the identification of secondary biomass potentials for biofuel production. The methodology, divided into four steps, defines the criteria that allow identification of promising scenarios of biomass supply chains for commercial application of innovative technologies. The model set up a scoring procedure based on carbon emission avoidance, efficient resource exploitation and sustainability indexes. Applying the four levels of analysis (biomass availability, suitability analysis, regionalization and multi-criteria analysis), the cereal straw supply chains in four European districts (Scandinavian, Hanseatic, Central European and Mediterranean) have been identified and grouped in 18 biomass supply regional clusters (BSRCs). The clusters represent the most promising hotspots where biomass availability, logistics and feedstock requirements for a novel conversion technology meet. Central European and Mediterranean districts are those with the highest cereal straw bioeconomic potentials which allow mono-feedstock supply chains and relatively high capacity of a conversion technology at 200 MWth and beyond. Central Europe has an overall bioeconomic potential of 16.249 kt (232.359 TJ) distributed over 36 regions and organized in 12 BSRCs. The Mediterranean district has an overall bioeconomic potential of 3541 kt (50.630 TJ) distributed over nine regions and organized in four BSRCs.

StrawFeed model: An integrated model of straw feedstock supply chain for bioenergy in China

With the growing concerns of fossil fuel scarcity and its negative impacts on global environment, bioenergy as an alternative energy source has attracted more attention as climate change mitigation. As one of the largest carbon emission and agricultural production countries in the world, China has abundant straw resources and great potential for energy utilization, and the number of straw-to-energy business projects is increasing dramatically. Correspondingly, there is a strong demand to design a stable and sustainable straw feedstock supply chain. However, due to the uncertainty of system boundary and neglect of potential risks, the procurement cost for bioenergy conversion plants (BCP) is varied significantly. Model is a critical approach in strengthening the understanding that leads to promoting supply efficiency. Therefore, an open-source & GIS-enabled linear programming model, named StrawFeed, is proposed to simulate the operation of straw feedstock supply. The costs of raking, baling, loading and transporting have been investigated as components in the StrawFeed model. The model is applied to case analysis of corn straw supply in Nongan county, a major corn production region in Northeast China. The results illustrate that the straw supply cost could be 172 CNY/ton, and the reasonable profit allocation mechanism could achieve the triple-win solution among farmers, brokers, and BCP. Furthermore, the challenges and opportunities for optimization are investigated with scenario analysis, based on unique circumstances and supporting policies in China. Unfavorable weather could delay the available working day, and thereby cost would increase up to 13%. The optimized scheme of straw utilization could achieve better environmental and ecological benefits, but the transportation distance for straw supply has to be expanded and the increased cost would be up to 53%. Cross-regional operation of agricultural machinery and machine procurement subsidies could reduce the cost by 18% and 5% respectively. This model is helpful to estimate accurate supply cost and deploy sustainable straw feedstock supply, which could contribute to assisting investors and policymakers for bioenergy industry in China.

Operation management of hybrid biomass power plant considering environmental constraints

Crop straw can not only be used as a raw material for bioenergy, but also can protect the soil after returning to the field. This research constructs a hybrid operation management model for combined power generation with multiple biomass fuels, with the purpose of exploring the impact of environmental protection on the operation and maintenance of biomass companies. First, the potential straw supply under different soil function protection scenarios was calculated. Based on this, a biomass power plant operation strategy was formulated under the mixed supply of multiple biomass. Lastly, taking Shandong Province as a sample case to verify the effectiveness of the model, we found that, (1) the theoretical amount of straw in Shandong Province in 2019 is about 78.57 million tons. Taking into account the agricultural, industrial and household use of crop straw, the total available straw in Shandong Province is 10.3–22.31 million tons. (2) owing to the heterogeneity of different straws, soil function protection will have great impacts on the inventory management of straw power plants. Reasonable straw allocation under different soil function protection scenarios can greatly improve the efficiency of different crop straws. In the case of high return to the field, the selection of maize decreased by 20%, and the amount of straw represented by potato increased by 40%. (3) Prioritizing soil function protection will reduce the total amount of straw that can be used for bio-energy production and reduce carbon dioxide emissions in the process of power generation. Therefore, when planning arbon capture and storage (CCS) technology based on straw power generation, the impact of soil function protection should also be fully considered.

Novel Methodology to Assess Advanced Biofuel Production at Regional Level. Case Study for Cereals Straw Supply Chains

Novel Methodology to Assess Advanced Biofuel Production at Regional Level. Case Study for Cereals Straw Supply Chains

Economic analysis of different straw supply modes in China

Choosing an appropriate straw supply mode is crucial for reducing straw supply costs. This study considers four different supply modes: Farmer-Factory mode, Farmer-Broker-Factory mode, Farmer-Centralized Storage Site-Factory mode, and Farmer-Broker-Centralized Storage Site-Factory mode. Comparing the advantages and disadvantages and economic analysis of each mode are conducted. It is found that straw collection includes artificial and mechanized collection, straw transportation includes tractor and truck transportation, straw storage includes open field storage and centralized storage sites. When collecting 100,000 tons of straw, ordering the different supply modes based on cost result an order (from high to low) of 1A, 3, 2A, 1B, 4, 2B, ordering them based on equipment demand result in an order (from high to low) of 1A, 3, 2A, 1B, 2B, 4, and ordering them based on labor demand result in an order (from high to low) of 1A, 3, 2A, 1B, 4, 2B. It also can be seen that collection cost, transportation cost, and loading and unloading costs are important components of supply cost for each mode. Through the analysis of the six modes, mechanized baling collection can significantly reduce supply cost and equipment and labor requirements. Although intermediate links are added, mode 4 has become an economical supply mode that is also suitable for large-scale straw utilization due to its mechanized operations. As a conclusion, it will likely be the main straw supply mode of the future.

Site selection of straw collection and storage facilities considering carbon emission reduction.

Straw recycling has generated high collection and transportation costs. Scientifically informed collection, storage, and transportation methods can reduce automobile exhaust emissions and high transportation costs. According to the relevant statistics, China's total theoretical straw resources reached 920 million tons in 2020. Due to such regional and seasonal straw surpluses, however, comprehensive utilization technologies need to be improved, and farmers' awareness of environmental protection needs to be strengthened. In some areas, open burning of straw is still practiced, causing environmental pollution and wasting resources. This study used cost and carbon emission metrics in a dual-objective planning model to plan the site selection of straw collection and storage facilities. Compared with the current manual calculation in various links in straw supply logistics, modeling can resolve the contradiction between cost and carbon emission considerations and can help meet the goal of Pareto optimum while ensuring supply, reducing costs for enterprises, and providing decision-making assistance for the government. This paper uses transportation theory and a dual-objective, mixed-integer model to study the field of biomass energy. Through the planning and design of the biomass raw material supply chain, the system efficiency is improved, and the studied company can obtain more profits. This article also explores the role of controlling carbon emissions in the field of biomass energy. It is believed that the government not only needs to guide corporate decision-making by charging carbon taxes but also needs to support enterprises in participating in the field of biomass power generation through active policy guidance.

Temporal and spatial availability of cereal straw in Germany\u2014Case study: Biomethane for the transport sector

BackgroundBy 2030, the German transport sector needs to achieve additional greenhouse gas savings of 67 million tonnes CO2-eq. and further progress requires swiftly implementable solutions. The fermentation of cereal straw is a promising option. Returning the digestate to the farmland can close agricultural cycles while simultaneously producing biomethane. The world's first large-scale, mono-digestion plant for straw is operational since 2014. The temporal and spatial biomass availability is a key issue when replicating this concept. No detailed calculations on this subject are available, and the strategic relevance of biomethane from straw in the transport sector cannot be sufficiently evaluated.MethodsTo assess the balance of straw supply and use, a total of 30 data sets are combined, taking into account the cultivation of the five most important cereal types and the straw required for ten animal species, two special crops and 12 industrial uses. The data are managed at district level and presented for the years 2010 to 2018. In combination with high-resolution geodata, the results are linked to actual arable fields, and the availability of straw throughout the country is evaluated using a GIS.ResultsDuring the analysis period and based on the assumption that in case of fermentation up to 70% of the straw can be utilised, the mobilisable technical biomass potential for future biomethane production is between 13.9–21.5 Tg fm a−1. The annual potential fluctuates considerably due to weather anomalies. The all-time maximum in 2014 and the minimum for the last 26 years in 2018 are separated by just 4 years and a difference of 7.6 Tg fm. However, large parts of the potential are concentrated only in a few regions and biomethane from straw could provide 57–145 PJ of a low-emission fuel, saving 3–12 Tg CO2-eq. in case of full exploitation.ConclusionDespite the strong fluctuations and high uncertainties, the potential is sufficient to supply numerous plants and to produce relevant quantities of biomethane even in weak years. To unlock the potential, the outcomes should be evaluated and discussed further with stakeholders in the identified priority regions.

Study of synergetic development in straw power supply chain: Straw price and government subsidy as incentive

Power generation from straw not only helps to meet the energy demands but also provides an effective way to dispose of straw. However, in order to boost straw power generation industry, many factors such as willingness of farmers, high collection cost and uncoordinated supply chain are the major issues need to be solved. In the present work, synergetic development of the straw power supply chain has been studied by establishing collaborative evolution model and the marginal utility of government subsidy has been defined. Our results showed that in farmer subsystem, the selling price of straw is the order parameter of the straw supply chain and has the positive feedback in straw supply chain system which can lead the development of the system. Increase in selling price can promote the synergistic development of the straw supply chain. The results indicate that the subsidies affect the synergetic development of the straw supply chain, and increase in government subsidies will promote the development of straw power generation system. The findings suggested that a government subsidy of 53 CNY/t would optimize utility, given the existing synergetic system. The results can be helpful for government policy makers to support straw power generation projects.

Sustainability assessment of straw direct combustion power generation in China: From the environmental and economic perspectives of straw substitute to coal

Straw power generation (SPG) can not only reduce dependence on coal, but also can convert agricultural waste into energy and alleviate environmental pollution. In order to address the major challenges such as sustainability of the SPG and to provide scientific ground from environmental and economic perspectives, a sustainability assessment model was established to evaluate the performance of SPG. Life cycle assessment (LCA), life-cycle cost (LCC) and the best-worst method (BWM) were integrated in the model. Four SPG scenarios were studied. The results showed that straw alternative coal-fired power generation had weak economic sustainability, the ratio of benefit to cost of SPG was 0.8752–1.1866. While, for the environmental dimension, a strong sustainability was obtained, the greenhouse gas (GHG) abatement potential of −0.8903 t CO2-eq t−1 straw. The findings obtained from the four SPG scenarios suggested that direct combustion SPG had great sustainability potential in China, and several factors such as straw supply chain model, pollutant treatment technology, transport vehicles and straw purchase cost were the main factors which lead to unfavorable economic performance. We suggest that the SPG schemes, transport models and financial subsidies should be carefully designed to improve the sustainability of straw power generation.

An integrated methodology for the economic and environmental assessment of a biorefinery supply chain

A supply chain network MILP model, developed by means of AIMMS software, and a process plant simulation model, developed by means of Aspen Plus®, are combined for the optimization of a biorefinery network. Optimization of the supply chain network is initially addressed using literature process and economic data. The results are used as input in the Aspen Plus® model where the technical and economic performance of the biorefineries is calculated rigorously. The two computational tools are iteratively executed until convergence on number, locations and size of the biorefineries and on process yield to products and total costs is achieved. The final results are used to perform the Economic Value and Environmental Impact (EVEI) analysis of the overall biorefinery network. The methodology is applied to a case study concerning the deployment of cereal straw in Germany to produce ethanol, ethyl levulinate and electricity. Optimization results reveal that the wheat straw supply network with four biorefineries is economically feasible and determines an environmental margin in terms of equivalent emissions savings of about 4 Mt of CO2 per year.

The Development of Straw-Based Biomass Power Generation in Rural Area in Northeast China—An Institutional Analysis Grounded in a Risk Management Perspective

Given a lack of consideration for the role and importance of stakeholders and the importance of stakeholders in the operation of biomass power plants in China, a comprehensive analysis oriented toward stakeholder risk management is needed to further develop the country’s biomass energy industry. Accordingly, we analyzed institutional factors that contribute to or constrain progress in biomass power generation in China. Data were collected from 275 straw suppliers (farmers) living around a biomass power plant, 15 middlemen, five power plant managers, and five local government officers. Interviews were held with all the participants, but questionnaires were additionally administered to the straw suppliers. Results showed that: (1) risk transfer in the biomass supply chain is one of the reasons why farmers are unwilling to supply straw; (2) middlemen are vital intermediaries between biomass power plant managers and farmers as a middleman-based biomass supply system is necessary to guarantee the quantity of straw supply, and; (3) the institutional structure that underlies the Chinese biomass energy industry is immature.