Modeling and simulation of inbound fuel logistics from regional collection stations to biomass powerplant in China

Abstract: With increasing environmental concerns from the use of fossil fuels in China, there has been increasing support by the government for the construction of new biomass powerplants. One of the most important and challenging aspects of bioenergy production is having a cost effective biomass supply chain. This paper investigated the optimization of biomass fuel supply to a newly constructed 100 MW powerplant located in Zhanjiang, Guangdong Province by modeling discrete events using EXTENDTM Sim7 software. A model was developed for biomass supply from 6 regional collection stations to the powerplant. The model was used to simulate the inbound delivery of biomass fuel to the powerplant. Simulation was used to analyze biomass flow beginning with loading at the collection stations to transportation to the plant-gate through sampling station. Testing of the moisture content of delivered biomass to determine whether the biomass needs to be dried was conducted primarily at the sampling station. For biomass which meets the powerplant moisture content requirement, trucks were weighed and the biomass was unloaded at the storage area. For biomass having moisture content above the powerplant requirement, the biomass was unloaded at a staging area where it was conveyed to a drying station to be dried before storage and use. In order to determine the discounted price for biomass dried, the amount of moisture removed during drying was determined by weighing the biomass prior to drying and after drying. Simulation was used to optimize the number of trucks and other events like sampling and unloading station, utilization efficiency of equipment, truck waiting time, and operation time for the system. The baseline logistics scenario was obtained using the initial number of equipment as designed parameter for the powerplant. Sensitivity analysis on how varying the number of equipment to affect the logistic performance was determined with simulation runs. Because of the intensive cultivation of land in China throughout the year, farmers have very little time from crop harvest to land preparation for the next crop. Therefore, powerplants have a very short period after harvest when biomass can be collected from fields for use. This time constraint demands that biomass delivery logistics must be optimized to deliver the maximum total available biomass within this period at minimum logistics cost. For other periods outside the harvest time, logistics was optimized to minimize delivery cost of biomass to the powerplant. The research can provide suggestions for optimizing the logistics of the fuel supply system of a biomass powerplant under China's unique agricultural situation.