Rice Husks Wood Vinegar from Simple Pyrolysis

Paddy plantation was ranked third after palm oil plantation and rubber plantation in Malaysia. Most of paddy plantation are located in the northern region of Malaysia. However, there is environmental pollution that occurs as a result of this agricultural activity. The open burning of agricultural waste such as paddy straw and rice husks causes severe air pollution, especially after the harvest season. The usage of fertilizer and poison which contains high chemical composition has led to water pollution. To reduce this problem, agricultural waste such as paddy straw and rice husks are processed to produce wood vinegar that can be reused. The production of wood vinegar from rice husk is produced using a simple pyrolysis system uses the concept of burning rice husks in combustion, then the smoke from the combustion is condensed in the condenser to produce water vapour as wood vinegar. A comparison of the use of cooling liquid is made to evaluate the condensation that occurs in the condenser. Cold water with an average temperature between 5 and 15 °C and tap water that has a temperature between 25 and 31 °C is used as a coolant. The use of different coolants has produced different results. Coolant from cold water produced 12 ml of wood vinegar in an hour compared to only 8 ml in an hour for coolant from tap water. This is due to large temperature difference in the inlet and outlet for cold water where it has increased the condensation process. Each sample uses only 150 g of rice husks. Based on the previous research by using the traditional method, only 5 ml of wood vinegar is produced within an hour. It clearly shows that simple pyrolysis system can increase more than 100% of wood vinegar production compared to the traditional method. Chemical content found in wood vinegar from rice husks were quite similar to wood vinegar produce by using Acacia barks, palm oil fruit bunches and coconut shell. The percentage of gas content in wood vinegar using rice husk is also almost the same as the percentage of gas content from other materials in the previous studies, where the average difference in gas content in wood vinegar from rice husk is only 2.8%. This shows that the production of wood vinegar from rice husk can be commercialized and expanded so that environmental pollution can be reduced and farmers’ income can be increased.