Preliminary plant design of thermochemical conversion for rice straw-based second-generation bioethanol production in West Java

Thermochemical conversion is selected in the design of a rice straw-based bioethanol production plant. This study examines the gasification and catalytic synthetic process technologies of rice straw into ethanol. The size of rice straw was reduced and dried before entering the gasification reactor to convert into syngas. The clean gas goes to the mixed alcohol synthesis process in a plug flow reactor with CuO/ZnO as a catalyst. The product is then purified through several separation methods, i.e., column distillation, stripping, and absorption. The controlled parameters for this plant are temperature, flow rate, pressure, level, and concentration. The paper describes the piping instrumentation diagram with a graphical representation of the equipment, piping, and instrumentation. A Heat Exchanger Network analysis achieves an efficiency of 34.4%. The electricity required is fulfilled by turbine expander for about 1,493 kW, and the rest of it is provided by PLN, besides an emergency generator sets. The capacity of this plant is 100,000 kL/year.