A model for designing the country’s agricultural waste-based integrated biorefinery (IBR) has been developed under a research project funded by the Department of Science and Technology-National Research Council of the Philippines (DOST-NRCP).

The DOST-NRCP said the research team, led by its member Michael Francis D. Benjamin developed a P-Graph (process graph) based Model for designing Philippine agricultural waste-based integrated biorefinery.

“Benjamin and team were able to develop sustainable designs, using input-output modelling, of a biomass-based integrated biorefinery or IBR where the country may achieve such eventual benefits,” it said in a statement.

The Council explained that an IBR refers to an integrated biomass processing plant or facility that produces several bioenergy products such as bioethanol, biodiesel, biofertilizer, and electricity using raw materials from rice production byproducts.

“Generally, IBRs decrease carbon emissions by avoiding uncontrolled and open burning of agricultural waste in the countryside, reduce dependence on fossil fuels, decrease the need for raw material as inputs, and produce various low carbon fuels,” it said.

The DOST-NRCP noted that the P-graph based method is applied to generate optimal and near-optimal IBR configurations utilizing the country’s agricultural waste as feedstock to maximize profitability.

Benjamin’s team initially created the P-graph framework to address process network synthesis (PNS), but they decided to extend its use beyond the PNS domain (i.e., integrated systems).

The P-graph software also presents the results in a graphical interface, a distinct advantage compared to other optimization techniques, the Council said.

"With the increasing demand and declining supply for fossil fuels globally, NRCP researchers saw the need for alternative fuels that are both renewable and sustainable. Given the estimated amount of biomass derived from agricultural waste or residue in the Philippines which is about 60 Metric ton/year or 400 Petajoule/year of energy, the utilization of bioenergy is essential in order to increase global energy security and mitigate the effects of climate risks via reduction of greenhouse gas emissions,” it said.

The DOST-NRCP study used rice straw, rice husk, and rice bran which are proven to contribute to sustainable energy generation in the country since its residues can generate biomass, a clean energy,

The P-Graph based model, using rice production waste, was able to show the results for optimal configuration of the IBR and the maximum profit to be generated, the Council said.

It said the local government units (LGUs) may use the results of the study in creating policies to maximize bioenergy production and increase the revenue generation of farmers.

"The results of this study will help in developing strategies to meet energy requirements of a certain locality through the utilization of available agricultural waste. According to researchers, there is likewise a potential for job generation and increased income for farmers resulting from sales of biomass,” the DOST-NRCP said.