MODELLING AND SIMULATION OF ENTRAINED FLOW GASIFICATION PERFORMANCE USING LIGNITE COAL AS FEED AND OXYGEN AS OXIDATOR WITH DRY FEED SYSTEM

• Main Author: Nabila Az-Zahra, Annisa
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/65843
• Institution: Institut Teknologi Bandung

Population growth results in an increase in food demand so that the use of fertilizers as plant nutrition is important. Fertilizer consumption in Indonesia is dominated by urea fertilizer which is made from CO2 and NH3. Ammonia is produced by reacting nitrogen from air and hydrogen which is obtained by reacting natural gas with water vapor. The main problem in the fertilizer industry is the supply of natural gas for the production process. One of the potential resources to substitute natural gas is hydrogen from coal gasification. In Indonesia, coal gasification technology for ammonia production has not been implemented. In addition, the replacement of existing technology into new technology needs to review aspects of cost and performance. Thus, studies and simulations are needed to see the gasification performance and optimal operating conditions to carry out the process by modeling and simulating coal gasification process. In this research, it is desirable that the gasifier output gas can be directly used for ammonia production. In this study, we want to know the model and operating conditions that produce gasifier product gas with ratio of nitrogen and hydrogen gas 1:3, the composition of gasifier product gas, the gasification output temperature, thermal efficiency, product gas-to-feed coal flow ratio, and the heat needed to conduct gasification. The modeling and simulation were carried out using ASPEN Plus V11 software. The results of the model validation carried out by modeling the Tunçbilek gasifier resulted in the mole fraction of the product gas being modeled almost the same as the mole fraction of the experimental product gas. The simulation produces gasifier product gas with ratio of mole fraction of nitrogen gas and hydrogen gas 1:3 with the most optimal operating conditions obtained when the mole fraction of oxygen in the air is 0.87, steam-to-coal ratio is 0.3, oxygen-to-coal ratio is 0.9, and the gasifier operating temperature is 1683.15 K. In the selected simulation conditions, the resulting thermal efficiency is 0.7326 and the gas rate-to-coal feed ratio is 2.26 kg/kg.