Biogas Technology Solves Farm Waste Disposal Problem
The dairy farm of the Philippine Carabao Center at Central Luzon State University (PCC at CLSU) in Science City of Munoz, Nueva Ecija generates an average of 630 kilograms of fresh carabao manure daily. Several years back, these wastes created disposal problems due to its bulkiness resulting in air and water pollution in the area.
Today, that is no longer a problem as the center has found an alternative waste management system through the adoption of biogas technology. And the other good news is that the center saves about 25 percent on its monthly cooking gas expenses by utilizing the biogas fuel (methane) generated from the biogas facility.
The biogas project was initiated in cooperation with the Provincial Science and Technology Center by Dr. Felomino V Mamuad, who is the director of :he PCC at CLSU and is currently the PCC deputy executive director. Called “Establishment of Biogas Digester as an Alternative Efficient Waste Management System,” it aimed to reduce pollution by creating awareness on the safe and effective waste management system for the increasing volume of carabao manure in the center.
Using the P 100,000-Grant-in-Aid funding from the Department of Science and Technology and the counterpart fund worth P20,856 from PCC at CLSU, the 62-square meter biogas digester facility was established in December 2007. It began its operation in March 2008.
According to Orlando G. Anselmo, the provincial science and technology director for Nueva Ecija, the biogas facility adopted the concrete, fixed dome design with a gas capacity of 16 to 20 cubic meters.
The facility, says Anselmo, generates methane from the carabao manure through the action of anaerobic bacteria. The resulting biogas can be used as fuel for cooking and electricity generation, among others.
The manure coming from the barn goes directly to the drainage where an inlet valve is connected directly to the fermentation chamber. In this chamber is where methane-producing bacteria act on the manure under anaerobic condition for 21-30 days, after which the methane gas will be available for use.
Anselmo said that the biogas digester has a hydraulic chamber, a built-in manhole measuring 40″ x 60″ placed between the digester/fermentation chamber and the gas chamber that regulates the gas pressure inside. Hence there is no danger of explosion.
A year after the biogas facility started in its operation; the dairy farm noted a number of good benefits derived from it. Economically, the biogas facility has been generating an average of 96 kilograms or almost 8.7 11-kilogram cylinders of liquefied petroleum gas (LPG). At a price of P500 per 11-kg LPG, this is equivalent to a P4,350 monthly savings on cooking fuel costs.
In addition, the sludge coming out from the digester is now being used to improve soil condition of forage pasture farm within the premises of PCC at CLSU. Anselmo said that the sludge is being diluted with water at 1:4 ratio and then applied to the grasses which gave favorable results. For this, the farm also saves on fertilizer costs.
On the environmental side, the farm has been efficiently disposing its animal wastes, preventing the emission of methane gas to the environment, which is many times more harmful than the atmospheric carbon in causing greenhouse effect. Now, all the manure excreted by 63 buffalos in the farm is directly fed into the fermentation chamber of the biogas digester.
The usual foul odor in the farm was also eliminated, and there is no need to worry about pollution of water table due to leaching.
The viability of biogas technology as proved by PCC at CLSU is now being used to demonstrate to interested livestock farm owners that it can be something useful for them to adopt. After all the benefits that it gives are well worth the investment.
By Melpha M. Abello