From kitchen waste to alternative source of gas

With the rising prices of liquefied petroleum gas (LPG) in the market, the Department of Science and Technology (DOST) has developed a machine that would convert kitchen waste to an alternative source of gas.



The Industrial Technology Development Institute (ITDI) produced an environment-friendly portable biogas digester that can store more than 211 liters of biodegradable kitchen waste which, when processed, can produce 350 liters of biogas for cooking with efficiency similar to regular LPG.



The waste-to-fuel process involves mixing 1.5 kilos of animal manure with 4.5 kilos of kitchen waste. The manure serves as the starter for fermented waste materials.



The drum-type biogas digester is an airtight, oxygen free vessel fed with organic materials where the microbial digestion takes place to produce the biogas. Materials needed for conversion to gas are kitchen waste and animal manure blended with water.



The ITDI said the process takes overnight and the gas produced is good for a day’s cooking, depending on the household’s consumption or frequency of use. The ITDI said the biogas digester best suits a small family’s gas requirement.



Aside from being a cheap source of cooking gas, the technology also reduces common kitchen waste, the ITDI said.



Data shows that Metro Manila alone produces about 600,000 tons of garbage daily.



The ITDI said previous biogas technology uses animal manure from poultry and hog raisers that emits unpleasant smells. "The new version discharges lesser, passing stench," it added.



The ITDI said sludge, on the other hand, could be used as organic fertilizer or soil conditioner.



The ITDI, one of the research and development institutes (RDIs) under the DOST, was created by virtue of Executive Order No. 128 dated Jan. 30, 1987. It is mandated to render a variety of technical services to local industries.



By HELEN FLORES