Vol. 11, Special Issue 12 (2022)

Author(s):
Chanchal Sahu, Khandetod YP, Mohod AG, Dhande KG and Aware SV

Abstract:
Rice is one of the most popular crops in the world generating significant amount of crop residues, majorly rice husk and rice straw. In Asia, where more rice and consequently more straw and husk are grown each year to meet the region's growing demand for food grains, managing these crop residues is still a challenge. Burning crop waste is also a fairly common practice in northern India which causes air pollution. The use of clean renewable energies has received a lot of attention due to the scarcity of fossil fuels and serious environmental issues. In such times, biomass like rice straw and rice husk becomes an important source of energy that can be directly transformed into solid and liquid fuels through pyrolysis. In this study, a batch type pyrolysis reactor was used to pyrolyse rice crop residues to produce better alternative fuels. Raw materials were characterized through bulk density, proximate analysis and calorific values to investigate their suitability as feedstock for this consideration. The pyrolysis unit, comprising of reactor, condenser, water pump, grate etc. was developed and operated in limited air supply to produce a hydrocarbon rich bio-oil, a carbon-rich bio-char and a gaseous mixture i.e. pyro-gas. Rice husk and straw were fed into the reactor and bio-oil, char and gases were produced, the liquid and char were collected separately while the gas was released into the atmosphere. The characterization and composition of the product yields were determined separately for the char and oil. The findings demonstrate that to produce 1 liter of crude bio-oil, 8.949 kg of rice husk or 20.548 kg of rice straw was required, to produce 1 kg of bio-char, 1.82 kgs of rice husk or 2.14 kgs of rice straw was required and to produce 1 kg of pyro-gas, 2.95 kgs of rice husk or 2.07 kgs of rice straw was required. The results show that if the pyrolysis conditions are chosen appropriately, it is possible to produce high quality alternative fuels from rice straw and rice husk that are comparable to fossil fuels.