Research on physical and chemical properties of pellets produced using paddy stalks for gasification process

Pellets which are produced using paddy stalks are the main type of biomass solid fuel and have great potential as a Bioenergy resource in the future of Turkey. But it also showed important problems because of its high content of ashes and its low gross calorific value, reducing the possibility to be used in domestic heating. In this research, the paddy stalks were chopped and then mixed with different materials such as coal powder, PVA (poly (vinyl alcohol)) and molasses before producing of pellets. In addition to these, only paddy stalk pellets without additive were produced to compare the other pellets. After preparation of the pellets, some physical and chemical properties of them were determined to investigate the effects of additives on the changing of these properties and gasification process. Pellet samples used in the tests were labeled according to additive percents are pellet produced using paddy stalk (PRF), paddy stalk + 3% PVA (PVA3), paddy stalk + 5% molasses (PML5), paddy stalk + 5% coal powder (PC5) and paddy stalk + 15% coal powder (PC15). Pellets were tested using downdraft fixed bed Gasifier. The volatile matters of PRF, PVA3, PML5, PC5 and PC15 were found to be in the range of 61.73 - 66.25%. Highest volatile mater found in pellets of PRF. Bulk densities were determined in the range of 494-606 kg/m3. Maximum bulk density was found for the PVA3 pellets. Highest ash fusion temperature was found to be 1436 °C for PRF pellets. The ash fusion temperatures indicate slag formation. The calorific values were changed in the range of 12, 18-12, 92 MJ.kg-1. The PC15 pellets has highest calorific value compared to the other pellets. According to research results, it can be recommended that the pellets produced from pellets produced using only paddy stalk for gasification by using appropriate equipment.