Analysis of Rice Husk Pellet Combustion Test for Co-Firing in Pulverizer Coal (PC) Boilers

Abstract

The increase of population has driven increased demand for energy, especially for transportation and electricity. Meanwhile, fossil energy production continues to decline, forcing the government to import petroleum to meet domestic needs. In order to anticipate the increasingly limited national fossil energy reserves and the increasing public energy needs, government is promoting the use of renewable energy. One of the efforts is by co-firing biomass in coal-fired power plants. At PLTU Indramayu, the selected biomass is rice husk which has undergone pelletization treatment, which is compaction and heating, in order to obtain biomass with a high density and calorific value better than the physical form of rice husk. Coal as fuel in PLTU Indramayu has an average calorific value of 4200 kCal/kg, while rice husk pellets have an average calorific value of 3400 kCal/kg. Combustion tests for co-firing need to be carried out to determine the operating performance of generating unit equipment. Co-firing tests in this study were still limited to a composition of 1% biomass and 3% biomass which required a total of 43.2 tonnes of rice husk pellets and 3196.8 tonnes of coal. Prior to the combustion test in the boiler, computational fluid dynamics (CFD) numerical simulations were also carried out to get an initial description. The results of the simulation and fuel tests show that the operating parameters are in normal limits. Equipments also shows good and normal performance. Likewise, the resulting emissions support the achievement of the quality standards required in the Minister of Environment Regulation No. 15/2019. Even so, tests still need to be carried out with a higher percentage of biomass composition in order to generate electricity from greater green energy and reduce use coal as fuel.