06 Powering the first biogas plant in Bicol
Powering the first biogas plant in Bicol

May 29, 2021

The Legazpi City Abattoir at San Roque, Legazpi City—the biggest and most modern in Bicol Region—is now rising to become the first abattoir in the region to embrace biogas technology, thanks to the collaborative project Piloting of Biogas Technology for Thermo-Electro-Mechanical Applications for the Legazpi City Abattoir of DOST-V through the Provincial S&T Center – Albay and the Local Government of Legazpi City. By utilizing 1.5 tons daily biodegradable wastes from swine slaughtering, it will mitigate public health hazards and environmental degradation by converting the waste to fuel for the abattoir’s boiler system, saving Php 1 million worth of annual expense from diesel fuel.

Through the Php 500,000 worth of project funding provided by DOST-V, the abattoir now contains a floating gasholder-type biogas digester, designed by DOST-V’s very own Albay Provincial S&T Director Engr. Jacinto Alexis B. Elegado. As counterpart, LGU-Legazpi allocated P450,000 for biogas generator, biogas scrubber and biogas refining setup.

In a radio-TV interview with DZGB-AM on 29 May 2021, Engr. Elegado and LGU-Legazpi City Veterinarian Dr. Manny Estipona announced that testing of the biogas digester using a heavy-duty gas burner already yielded blue flame. In addition to ensuring contamination from chemicals that may kill the methanogenic bacteria responsible for methane gas production, the biogas digester’s usage was designed and incorporated with safety auxiliaries such as pressure gauges and automatic shut-off valves.

The second phase of the project will focus on converting the biogas to mechanical energy to drive the motor and covert it to electrical energy through a generator attachment. A study on purifying the biogas from 50% to 100% methane so it can be compressed in LPG tanks to be used by LPG taxis is also underway. The biogas digester can generate 3kg/day LPG or equivalent to 113 LPG tanks annually, and 104 tons of high-grade fertilizer plus liquid effluents as no-odor-fertilizer. With effluent pollutants reduced to 35%, water from the digester can be released with no harmful effects on the environment.

The biogas digester will also generate organic fertilizer from sludges which can be added with swine hair to produce a slow-release, high-grade organic fertilizer. With the current reliance on inorganic fertilizer, this production will greatly assist in the Department of Agriculture’s goal of increasing organic matter in all farming systems.

According to Dr. Estipona, Legazpi City Abattoir presently pioneers the use of biogas technology in the Philippines as a solid waste management program and solid waste diversion program. Other LGUs are looking forward to the success of the project to replicate the technology in their respective areas.

On whether the sludges in the rivers in Legazpi City can also be fed to the biogas digester, Engr. Elegado explained that it is possible; however, it will entail costs on assimilation tanks for segregation. The biogas technology is also applicable to poultry, since the best biogas producer are those from chicken manure, then from cow and carabao manure.

The interview with Engr. Elegado and Dr. Estipona during the 29 May 2021 episode of DZGB-AM’s program “Boses kan Kapalibutan” can be viewed at (EngrJABElegado/ABImperial, PSTC-Albay)