Optimization analysis of carbon emission reduction from crop straw collection and transportation under the sustainable development goals

Abstract: Recycling and utilization of crop straw have been one of the most important ways to treat the resource waste and environmental pollution in rural areas in the context of the United Nations Sustainable Development Goals. In this study, a collection and transportation model was established to optimize the number and the recovery distance of storage points with the carbon emission reduction from the straw collection. A research object was taken as the collection and transportation system with a square area in the biomass power plant in Hebei Province of China. A systematic investigation was made on the resource distribution, biomass potential and household power consumption demand, further to evaluate the matching degree of straw resources supply and demand in various cities. Different collection systems were compared under the direct combustion and gasification power generation from the perspective of collection range and emission. The constructed system was then comprehensively evaluated in terms of economy, environment, and efficiency. According to the sustainable development goals, some recommendations were proposed to promote the low-carbon recovery and efficient utilization of straw resources. The research results show that there were excellent collection conditions in most areas rich in straw resources, with an annual output of 44.755 million tons. The straw output per unit area was 645.97 t/km2 in the study area. There were high power demands in Langfang, Cangzhou, and Tangshan Cities, but the supply of straw was tight, indicating the low matching degree of resource supply and demand. The straw collection and transportation system with the best emission reduction benefits was set as 12 collection storage points around the power plant, where the vertical distance between each collection storage point and the recycling boundary was 0.25R (R is the vertical distance from the power plant to the collection boundary). The transportation emissions were reduced by 83.98%, and the regional greenhouse effect was effectively controlled in the system, compared with no storage points. The collection efficiency increased by 18.75% than before, indicating cost-saving, low carbon, and free of collection blind area. The constructed system was greatly contributed to the circular radiation collection mode for the better utilization of waste resources. The high efficiency, low-carbon, and economic properties were found in Zhangjiakou and Qinhuangdao Cities, but less in Langfang and Cangzhou Cities. In addition, the multiple dimensional support 10 sustainable development goals were related to environmental protection, poverty reduction, public health, and resource utilization. The power generation efficiency can also determine the market competitiveness of biomass technology in sustainable agriculture. A closed-loop supply chain of biomass circular energy can be constructed to promote the low-carbon path for agricultural modernization and sustainable energy in rural areas.