Effect of Different Gas Turbine on Integrated Gasification Poly-Generation Plant with Methanol and Power Generation

The present study performed a system-level simulation model for poly-generation applications, based on gasification technology with the commercial chemical process simulator, Pro/II® V8.1.1. There are five major blocks in the poly-generation plant, i.e. air separation unit (ASU), gasification island, gas clean-upunit, combined-cycle power block, and methanol synthetic unit. In order to simulate the actual situation in Taiwan, the kaltim prima coal (KPC) from Indonesia which is general used in Taiwan was adopted in the study as feedstock. The gasification technology is adopted GE gasifier. In the power block, two gas turbine types of GE 7FB and MHI M501G are considered in the study. The others processes are referred from commercial processes. Two poly-generation cases are evaluated in the study based on the two gas turbine types. The ratio of syngas delivered to methanol synthetic unit and power block is difference due to the total syngas flow rate from gasification island is kept as constant based on two commercial gasifiers. In the GE 7FB case, the ratio of syngas delivered to methanol synthetic unit and power block is nearly half to half, the CO2 emission is 265.7 t/h, net system efficiency is 46.1 %(HHV). In the MHI M501G case, the ratio of syngas delivered to methanol synthetic unit and power block is nearly 31 % to 69 %, gross system efficiency is 50 %(HHV) and net system efficiency is 43.5 %(HHV). Although the performance of MHI M501G is higher than GE 7FB, the higher efficiency is obtained in syngas converted to methanol. The lower amount of syngas delivered to methanol synthetic unit decreases the overall system efficiency. The simulated results showed the benefit of the poly-generation plant. The higher efficiency is expected to adopt relative higher efficiency gas turbine in the poly-generation system if the ratio of syngas delivered to methanol synthetic unit and power block is set as the same in the two cases.