HORTICULTURE

Detailed explanation-1: -The combustion efficiency tends to decrease with increasing percent excess air. However, the maximum combustion efficiency is obtained at EA = 50%. The combustion efficiencies at EA = 40%, 50%, 60% and 70% are found to be 94.7%, 95.8%, 94.1% and 94.3%, respectively.

Detailed explanation-2: -The boiler’s efficiency found the same as using of coal (68%) with the rice husk calorific value 15, 217. 20 kJ/kg that means rice husk is cheaper fuel than coal [2, 30] .

Detailed explanation-3: -The first rice husk furnaces were reported in scientific literature around 100 years ago. It was used in a rice mill in Myanmar as fuel of the boiler that created steam used for powering a rice mill with a steam engine (International steam, 2015; How steam engine work, 2015).

Detailed explanation-4: -The rice husk’s calorific value was relatively low 14, 852 kJ/kg caused low heat value of rice husk charcoal, therefore not very high at 19, 859 kJ/kg.