Effect of water content and cassava starch and densification pressure on the quality of bio-pellets made from rice husks
Norman Iskandar (a*), Sulardjaka (a), Sri Nugroho (a), Munadi (a), Rilo Chandra Muhamadin (a), Deni Fajar Fitriyana (b)
(a) Department of Mechanical Engineering, University of Diponegoro
Jl. Prof. Sudharto SH, Tembalang Semarang 50275, Indonesia
*norman.undip[at]gmail.com
(b) Department of Mechanical Mechanical Engineering, Semarang State University
Jalan Taman Siswa Sekaran, Gunungpati Semarang, 50229
Abstract
Rice husk is a waste that has a very high amount every year and is spread in several islands in Indonesia. The use of rice husk as a source of energy raw materials is still very low. Rice husk itself in terms of potential amount and distribution has the potential to become a renewable energy source for rural areas so that it can overcome the problem of rural energy needs. By modifying rice husks into bio-pellets, rice husks can be a source of energy for the daily needs of rural communities and it is possible to support the industrial sector in rural areas so that the reach of rice husk waste can be increased and economic functions also increase. The bio-pellet quality reference standard made refers to the SNI standard. To make bio-pellets, flat die mill type machines are used with speeds of 1660 rpm. As an adhesive used cassava flour with a variation of 10% and 20% and a variation of water 15%; 20% by weight of rice husk. Compaction pressure varies by adjusting the gap between the roller and die with a distance of 0.5mm, 1mm and 1.5mm. From the results of testing the characteristics of bio-pellets that have been carried out, the best bio-pellet is obtained from bio-pellets which are processed from a mixture of rice husk with the addition of water by 20% with a roller and die gap of 1.5 mm and an adhesive of 20% where the calorific value is 4182 cal/gram. Of the five SNI standard parameters, for the ash standard, the product made cannot meet the maximum value of the ash standard, namely ash content ≤ 1.5%. For other standards such as having a calorific value of more than 4000 cal/gram, the bonded carbon value is ≥ 14%. Volatile content is less than ≤ 80% and has a density of ≥ 0.8 already fulfilled.
Keywords: biomass; bio-pellets; cassava starch; renewable energy;rice husks; SNI
Topic: Mechanical Engineering