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The agricultural waste is large in number and the utilization rate is extremely low in China, requiring remediated. Formatting the project system and introducing the Public-Private-Partnership (PPP) mode are inevitable to realize the specialization and socialization in resource utilization of agricultural wastes. However, the confusion of financing, management, responsibilities of participants and difficulties in coordinating interests limit the expected effect of the resource utilization of agricultural wastes (RUAW). To this end, combined with the examination of actual cases, this paper constructs a tripartite evolutionary game model of RUAW PPP projects among local government, social capital and farmers, then conducts simulation and case study. We find that the local government does not supervise, social capital acts opportunistically, and farmers choose to cooperate is the evolutionary stable situation, and the cost of supervision for local government and the reward and punishment mechanism of local government to social capital will largely influence the strategy choice of the stakeholders. Strengthening the local government's sense of responsibility and regulatory capacity, optimizing the reward and punishment system, vigorously making technological innovations, and improving the operational capacity of the special purpose vehicle can effectively improve the efficiency of cooperation. The results of the study have some guiding significance for further improving the level of circular agriculture in China even in developing countries and forming a more complete system of resource utilization of agricultural wastes. • The PPP model was used in projects of resource utilization of agricultural wastes. • The local government plays an important role in coordinating between social capital and farmers. • The probability that the social capital will act opportunistically in the PPP project is extremely high. • Farmers' willingness to cooperate is sometimes fragile. [ABSTRACT FROM AUTHOR]

• This paper regards the interests of farmers and supermarkets as the criterion to measure the stability of agricultural supermarket docking supply chain, analyses the impact of traditional risks and risks brought by big data on the stability of agricultural supermarket docking supply chain, and draws rational risk control measures from the perspective of maximizing the interests of both sides of agricultural supermarket docking. • This paper analyses the problems existing in the agricultural supermarket docking supply chain, and identifies the risks from four aspects: production and processing, distribution and retail sales, including the new risks brought by the introduction of big data. • In this paper, the fuzzy multi-dimensional preference analysis linear programming method is used to extract the risk evaluation index system, and the hierarchical analysis method is used to evaluate the risk of the supply chain under the mode of "agricultural supermarket docking", so as to realize the scientific risk assessment of the supply chain which involves multi-agent, multi link and multi-standard. With the application of big data in all walks of life, big data thinking is effectively improving the circulation efficiency of agricultural products supply chain by driving management changes in business decision-making and "farmer-supermarket docking" as an innovative mode of agricultural products circulation. Based on the current situation of China's agricultural supermarket supply chain development, this paper makes an in-depth study on the supply chain risk of agricultural products of large retail enterprises under the mode of "agricultural supermarket docking", and then introduces the agricultural supermarket docking supply chain under the big data environment. This paper uses big data to analyze the risks that may arise in the supply chain of "agricultural supermarket docking" in large retail enterprises. This paper from the aspects of production, processing, distribution, retail and consumption, introduces the new risks of agricultural supermarket supply chain after introducing big data. Secondly, Qualitative analysis and quantitative calculation are combined to conduct risk assessment. Through empirical analysis, the ranking of all risk factors is obtained, and the relevant fuzzy evaluation grade and risk evaluation criteria are given. Through expert evaluation, a new risk ranking is also obtained, which is not much different from the results of empirical analysis, and the empirical results are also verified. Therefore, develop this study is helpful to prevent the risk of agricultural supermarket supply chain connection. At the same time, the information integration, sharing and feedback of the big database provide a new idea for the optimization of the supply chain connecting agricultural production.it also has reference significance for other supply chain risk management. [ABSTRACT FROM AUTHOR]

China has a long history of utilizing biogas technology for the treatment of waste and the production of energy. This paper reviews the development and technology of the three types of biogas digesters used in China: household-scale digesters, biogas septic tanks, and biogas plants for the treatment of municipal, industrial, and agricultural waste. The structure of household-scale digesters is simple and practical; the basic type is the fixed-dome digester, also called the hydraulic digester. The biogas septic tank for sewage treatment is a combination of the traditional digester, an anaerobic filter, and a facultative filter. Biogas plants apply several different processes depending on the type of waste treated. The treatment of municipal waste biogas is conducted using the completely stirred tank rector (CSTR). The upflow anaerobic sludge blanket (UASB) is the most common technology used in the anaerobic treatment of industrial wastewater, followed by the CSTR and the anaerobic contact (AC) process. The treatment of agricultural waste mainly employs traditional hydraulic digesters, while newer biogas plants use advanced anaerobic processes such as CSTR and UASB as well as upflow solids reactors (USR) and upflow blanket filter (UBF) reactors. Biogas plants for agricultural waste are classified as small, medium, large and super large based on the scale of biogas production and digester volume. Although small-scale biogas plants are the most common, large-scale biogas plants produce the largest biogas output. With the changes associated with socio-economic development, the growth of household-scale digesters will slow down in the future. As central sewage treatment networks become more widespread, biogas septic tanks will be confined to villages and small towns. The development of biogas plants holds the most growth potential for the future. [ABSTRACT FROM AUTHOR]

The over-intensification of cultivated land has created increasingly obvious negative effects that threatened national food security. The sustainable intensification of cultivated land use (SICLU) has become a critical path to balance the economic and ecological benefits of agricultural production. However, the definition and evaluation of SICLU is still incomplete, and the systematic study of SICLU is lacking. This paper built an SICLU evaluation index system based on emergy analysis and used it to determine the SICLU during 2000–2017 in China. And then the influencing factors of SICLU were investigated. We found that: (1) the overall SICLU in China has a weak "U"-shaped trend, first decreasing during 2000–2006 and then increasing during 2007–2017; (2) the Western region has the highest average value of SICLU, followed by the Northeastern and Central regions, and then the Eastern region during 2000–2017; (3) the spatial-temporal pattern of the SICLU reveals that the number of provinces with low level (the first or second grade) slightly decreased generally, the number of provinces with medium level (the third or fourth grade) increased in general, while the number of provinces with high value (the fifth or sixth grade) has been small and stable; (4) the influencing factors indicate that rural per capita net income and per capita planting area of crops play significant roles in promoting the SICLU, while the agricultural disaster rate, effective irrigation rate, multiple cropping index, and rural labor non-agricultural employment rate have significant inhibitory effects on the SICLU at the national level. These findings capture the resource and environmental performance of the cultivated land use system and have important implications for promoting cultivated land intensive use transition and the sustainable development of agriculture in China. • An evaluation index system was established to evaluate the SICLU based on emergy analysis. • The outputs of cultivated land use include agricultural products, ecosystem services and agricultural wastes. • The spatial-temporal pattern and influencing factors of SICLU in China were explored. • Suggestions were proposed to improve the SICLU level and promote cultivated land green transformation. [ABSTRACT FROM AUTHOR]

Tobacco is widely planted across the world especially in China, which means that a large amount of tobacco waste needs to be treated. This study investigated the biogas fermentation of tobacco stalks co-digested with different biomass feedstocks and the inactivation of Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV) by anaerobic digestion. Results showed that the maximum methane yield of tobacco stalks at 35 °C was 0.163 m 3 CH 4 ⋅kg VS −1 , which was from the co-digestion of tobacco stalks, wheat stalks and pig manure. The largest VS removal rate of tobacco stalks was 59.10%. Proven by indicator paper stripe, half-leaf lesion and RT-PCR, CMV could be inactivated by mesophilic and thermophilic anaerobic digestion, whereas TMV could be only inactivated by thermophilic anaerobic digestion over 20 days. These results suggested that using tobacco stalks as feedstock for anaerobic digestion and applying the digested residue and slurry to Solanaceae crop land are feasible. [ABSTRACT FROM AUTHOR]

The increasing importance of lignocellulosic biomass as a renewable energy source has led to an acute need for reliable and detailed information on its assessment, consumption and supply. With the passage of China’s legislative targets for renewable portfolio standards, agricultural residue resources have the potential for an increasing role in meeting liquid fuels demand in China. An assessment of current and near future agricultural residue resources (including agricultural crop residues and secondary agricultural processing residues) in China at national scale was conducted. This paper gave the theoretical quantity, collectable quantity, usable quantity and potential quantity for liquid biofuel production of agricultural residues in China. The spatial and seasonal distributions of crop residues were analyzed. The theoretical output of crop residues in China at national scale in the near future were forecasted by means of an artificial neural network (ANN) model. The availability of agricultural residues in China was presented, as a result, the potential of liquid biofuels from agricultural residues was discussed. The ANN predicted results have shown that the theoretical output of crop residues in China at national scale will be up to 930.8 million tons in 2015. About 44 million tons per year of bioethanol or 131 million tons per year of bio-oil would have been produced, if the total usable output of agricultural crop residues were used to produce bioethanol through biochemical conversion process or bio-oil through fast pyrolysis, which could replace 26.9 million tons of gasoline or 58.2 million tons of diesel at national scale in 2015, respectively. The above results will be helpful for commercialization of bioenergy industry and their market-oriented development strategy, so as to accelerate the development of industrialization of biofuel technologies. [ABSTRACT FROM AUTHOR]

Abstract: Biomass can be relatively easily stored and transported compared with other types of renewable energy sources. Crop straw can be converted into densified solid biofuel via briquette fuel technology to expand its possible applications and enhance its utilisation efficiency. However, the potential economic, environmental and social impacts of crop straw briquette fuel need to be assessed before its large-scale use. This paper provides a comprehensive evaluation of these impacts for a fully-operating 2 × 104 t/a corn stalk briquette fuel plant in China. The results show that with a life time of 15 years, a purchase price of 150 RMB/t for corn stalk and the current sales price of 400 RMB/t for briquette fuel, the plant has a net present value of 9.6 million RMB or 1.5 million USD, an internal rate of return of 36% and a short investment payback period of 4.4 years. The life cycle greenhouse gas emissions are found to be 323 t CO2,e/year or 1 kg CO2,e/GJ, much lower than that of coal. Additionally, the process reduces pollution by decreasing the amount of corn stalk that is discarded or burnt directly in the field. In terms of social impacts, the use of corn stalk briquetting fuel plant is expected to play an important role in increasing local residents' income, improving rural ecological environments, alleviating energy shortages, guaranteeing energy security, and promoting socialism new rural reconstruction. [Copyright &y& Elsevier]

Producing biogas from agricultural waste by using a household biogas digester has a critical role in increasing energy supply and reducing greenhouse gas emissions in rural areas. However, only a few studies have analyzed the type of animal husbandry and planting that influence household biogas. This paper analyzes the spatial-temporal distribution of household biogas and its proportion in the total biogas produced in rural China from 2009 to 2018. The correlation between household biogas in rural China and animal husbandry and planting from 2009 to 2018 is also examined. The types of animal husbandry and planting that influence household biogas are then respectively determined via ordinary least squares and geographically weighted regression. Results show that the spatial-temporal distributions of household biogas with maximum and minimum values of 1.384 × 1010 m3 in 2011 and 0.8420 × 1010 m3 in 2018, respectively and its proportion with maximum and minimum values of 94.83% in 2009 and 75.07% in 2018, respectively significantly vary and show a declining trend from 2009 to 2018. The number of cattle and pigs is identified as the main animal husbandry factor that influences household biogas, whereas the planting areas of vegetables, fiber, and tobacco were identified to be the main planting factors. Considering fitting effects, R2 and adjusted R2 values of 0.8620 and 0.8100 obtained by geographically weighted regression respectively, were higher than those of ordinary least squares (0.6480 and 0.6220, respectively), respectively in animal husbandry factors, whereas R2 and adjusted R2 values of 0.8400 and 0.7990 obtained by geographically weighted regression, respectively, were higher than those of ordinary least squares (0.7190 and 0.6880, respectively) in planting factors. These results provide a reference for planning the production of biogas and the utilization of agricultural waste. [Display omitted] • Reveal spatial-temporal differences in the household biogas. • Show spatial-temporal distribution of proportion of household biogas in total biogas. • Determine correlation of household biogas with types of animal husbandry and planting. • Identify types of animal husbandry and planting influence household biogas. • Reveal spatial heterogeneity of the type of animal husbandry and planting. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes an inventory analysis for the household biogas system in Gongcheng, China. The results show that (1) Biogas-linked agro-ecosystem has a longer utilization chain for agricultural wastes, which takes in nonrenewable resources and outputs renewable resources. Therefore, household biogas system is an effective measure in relieving energy shortage, reducing environmental pollution and realizing the sustainable agriculture in the rural areas. (2) The efficiency of the household biogas system is at a low level, and still needs to be promoted. In order to increase the energy conversion efficiency and energy use ratio, more attempts should be dedicated to the technological advancement of biogas fermentation and multipurpose utilization. (3) The proposed method may help us understand the household biogas system more clearly and directly in energy conversion and utilization mode based on energy metrics. It is convenient to find out the weak points of the agro-ecosystem that waste more energy and seek for optimal solutions accordingly. [Copyright &y& Elsevier]

Abstract: This paper assesses the sustainable biomass resource for energy in China. Assessment has been carried out for the following resources: (i) agricultural residues, (ii) forest residues, and (iii) municipal solid waste (MSW). The potential of each resource is estimated for the base years 2008, 2008, and 2007. The energy potentials of these resources in 2008, 2008, and 2007 are estimated to be 14.7, 3.9, and 0.2EJ, respectively. The total potential including the energy of 6.4EJ from the proposed low-input high-diversity (LIHD) grassland biomass on the untilled lands for the base years 1996 is equal to about 30.2% of China’s energy consumption in 2008. Furthermore it is projected that sustainable biomass use for energy will reduce net emissions of green house gases (GHG) of 3276.7 million tonnes, and help in emission-reduction target of China and the world. [ABSTRACT FROM AUTHOR]

Abstract: Agro-residue is one of the important biomass resources in China and its efficient utilization is crucial for providing bio-energy, releasing risk of environmental pollution, and enhancing rural incomes. Densification is one of the important utilization routes of agro-residues. The objective of this paper is to explore the development of agro-residue densified fuel in China based on energetics analysis. The energetical property and energy potential of main agro-residues in China were firstly analyzed and then the development of agro-residue densified fuel in every region was evaluated based on energetics analysis. The results show that the main agro-residues in China are good feedstocks as densified fuel and they constitute enormous energy potential for developing densified fuel. However, the situation of every region should be considered for the development of agro-residue densified fuel. The primary energy embodied per unit of useful energy indicates that most of the regions in China are suitable for developing agro-residue densified fuel as it is energetically advantageous compared with coal, whereas only about 25% of regions near coal production locations are not suitable as they are less energetically advantageous. [Copyright &y& Elsevier]

• A new approach for the prediction and optimization of syngas production is proposed. • A numerical model for the study of biomass gasification is established. • Agricultural wastes of northeast China are first reported for gasification study. • The effects of operating conditions and biomass composition on syngas are studied. • The techno-economic analysis of three different agricultural wastes is carried out. Prior information regarding the effects of the operating conditions and biomass composition on the syngas production is critical to predict and optimize the syngas production. Therefore, this paper proposes an effective method to predict and optimize the syngas production by combining a process model and data analysis techniques. Three agricultural waste types from Northeast China and 56 biomasses with different compositions were used as the gasification feedstock to investigate the effects of the operating conditions and biomass composition on the syngas production. A validated Aspen Plus process model was implemented to realize the biomass gasification process and techno-economic analysis. The sensitivity analysis results indicated that a lower temperature (approximately 600 ℃) and lower steam-to-biomass ratio (S/B) (approximately 0.1) were the optimal operating conditions to achieve a higher lower heating value (LHV) of syngas. The introduction of steam changed the relationship between the temperature and LHV of syngas from inverse to direct. Furthermore, the performance comparison of the three agricultural waste based gasification processes indicated that a higher temperature and higher S/B could weaken the effect of the C, H, and O contents on the syngas composition. More importantly, the partial correlation analysis of the 56 sets of simulation results highlighted that a higher content of C and H, C/O and C/H helped enhance the LHV of syngas. The C/O value and C content exhibited the most significant correlations with the LHV of syngas, with correlation coefficients of 0.945 and 0.840, respectively. Correspondingly, these parameters exhibited a reasonable linear response with the LHV of syngas, with R2 values of 0.864 and 0.533, respectively. Finally, the techno-economic analysis indicated that SS is the optimal feedstock for syngas production. [ABSTRACT FROM AUTHOR]

The accumulation of waste biomass and plastic and the inefficient combustion of low-quality coal is a major cause of energy loss and air pollution in rural China. This paper reports for the first time an experimental and multi-perspective analysis on an industrial scale co-pyrolysis of waste biomass and plastic. The results show that the resulting biochar product had a low calorific value of ≥21.0 MJ/kg, which meets the national standard for commercial solid fuel (GB/T 31862–2015). The calorific value of the produced gas was over 10 MJ/m3 and met the requirements of the national standard for residential heating and cooking (GB/T 13612–2006). The products of the co-pyrolysis can replace 1100 t of standard coal per annum, and reduce carbon dioxide emissions, sulfur dioxide emissions, smoke, and other contaminants at the rate of 1720 t, 5–6 t, and 320 kg, respectively, as well as reducing smoke pollution. In addition, through the recycling of 750 t of plastic waste per annum for use in the co-pyrolysis, this method can reduce the white pollution of 50–66.7 km2 of farmland in the local area. The present study can guide the optimization of such systems and lead to adequate flexibility in the co-pyrolysis of different wastes to generate economic and socioenvironmental benefits. Image 1 • Industrial co-pyrolysis of biomass, waste agricultural film, and low-quality coal. • Systematic analysis of energy flow and economic and socioenvironmental benefits. • Biochar and fuel gas calorific values reached 21.0 MJ/kg and 10 MJ/m3, respectively. • The project annually reduces 1100 t of coal combustion and 1720 t of CO 2 emissions. • Recycling agricultural film reduces white pollution on 50–66.7 km2 land annually. [ABSTRACT FROM AUTHOR]

Biomass power is one of the most important renewable energy sources in China. In order to provide a reference for China's biomass power planning, this paper builds a power sector-planning model using the Long-range Energy Alternatives Planning System (LEAP). The results show that in the base scenario, the installed capacity of agricultural and forestry residues, municipal solid waste and biogas will increase to 22350 MW, 21150 MW, and 4900 MW, respectively by 2030. From the point of view of total volume, biomass supply is not a constraining factor for biomass power source. However, there are some social and economic factors that impede the development of the biomass power industry, some of which may not be addressed in the short term. Therefore, the development of the biomass power industry in China is a long-term process. Some policy suggestions were proposed, including reasonable planning and more subsidies for biomass supply value chain. • An optimal power-planning model focused on bio-energy in China was developed. • Agricultural and forestry power, waste power and biogas power were all analyzed. • Social and economic factors that impede biomass power were investigated. [ABSTRACT FROM AUTHOR]

• Agricultural residue wastes can be valorized through its conversion into LCNF. • WS fibers with low lignin and ash content can be easily fibrillated to LCNF. • Post-purification treatment can further decrease lignin content and fibril diameter. • P-LCNF isolated from WS presented higher CrI and SSA values than those from WWS. Each year millions of tons of agricultural wastes are produced, however, not well utilized in China. Considering the economic development and environmental protection, the valorization of these wastes is increasingly necessary and important. Here we used p -toluenesulfonic acid hydrolysis followed by mild disk grinding for on-farm valorization of wheat straw (WS) and their pulping solid residue (waste wheat straw, WWS) to produce lignocellulosic nanofibrils (LCNF). Alkaline peroxide post-treatment was further conducted to obtain purified lignocellulosic nanofibrils (P-LCNF) with lower lignin content and thinner diameters. The raw materials and resulting LCNF and P-LCNF were investigated in each process for their chemical component, crystal structure, morphology, and thermal properties. Interestingly, although WS fiber had higher lignin content than WWS fiber, the WS fiber with lower ash content resulted in LCNF and P-LCNF with smaller height and lower thermal stability, but higher crystallinity and higher specific surface area. Higher ash content in WWS fiber protected cellulose and lignin from depolymerization and degradation, respectively, which endowed LCNF and P-LCNF with entangled network structure. Overall, this study indicated that the low-temperature fractionation process on WS and WWS fibers could yield cellulose nanomaterials with potential value-added application and achieve the efficient utilization of agricultural wastes. [ABSTRACT FROM AUTHOR]