MANILA, Philippines — San Carlos Bioenergy Inc. (SCBI) is investing P200 million to put up infrastructure that will boost its biogas output and address concerns of odor from its ethanol plant.
SCBI, which is one of two ethanol facilities of Roxas Holdings (RHI) located in San Carlos City, Negros Occidental, is putting up two units of anaerobic digesters (ADs) worth P200 million as part of its commitment to protect and preserve the environment.
The firm said the ADs would handle 1,000 cubic meters of spent wash generated from ethanol production.
The project began in March 2017 and is expected to be completed in September this year. Commissioning and biological process startup will follow after the completion of the ADs.
SCBI said the ADs are designed to generate about 52,000 cubic meters of biogas per day, a clean and renewable energy resource.
RHI environment head Roselle Recreo said the biogas would be utilized in combination with other biomass, as fuel to produce the power requirement of the plant, replacing an equivalent of 100 tons of bagasse per day.
Aside from generating clean and renewable fuel resource, the full operation of the two ADs would mitigate the odor occurrence.
Recreo said ethanol plants face the challenge of managing distillery slops – also known as spent wash – which is the resulting water, colored dark brown, from the production of ethanol from molasses.
“Theoretically, for every one liter of ethanol, we produce 10 to 12 liters of spent wash. Its characteristic color, acidity, and very high level of organic matter make it one of the most challenging types of wastewater to manage,” she said.
“Being organic makes it very vulnerable to natural fermentative actions resulting to formation of various volatile organic compounds (VOCs) – some of which may emit gases (some with natural characteristic odors). Knowing these natural biochemical reactions has provided the plant better control of the potential effects of wastewater on the environment,” Recreo said.
Before completing the ADs, SCBI said it applies daily doses of NCH-bioamp freeflow activated microorganisms for odor control.
The AD project is part of the company’s initiatives to manage concerns such as the odor from distillery slops, reassuring the city government and residents of its unwavering commitment to protect the health of the people and preserve the environment.
SCBI executive vice president and COO Luis Villa-Abrille said the company values its commitment to protect and preserve the environment as it supports the global initiatives of the United Nations Development Programme’s Sustainable Development Goals of 2030.
The AD infrastructures that SCBI is putting up will not only generate clean energy, which also supports climate change initiatives by reducing the emission of greenhouse gases. The plant is also continuously exploring and implementing various programs on sustainable resource consumption.