BREAKTHROUGH: Gasifier using rice hull as fuel

A rice hull-fueled gasifier-engine system suited for shallow tube well irrigation has been devised by agriculture engineers of the Department of Agriculture-Philippine Rice Research Institute (DA-PhilRice).

Actually, the device was adapted from the rice hull gasifier of the University of California Davis (USA) to suit Philippine conditions.

The feat was achieved by DA-PhilRice researchers Rizaldo Aldas, Ricardo Orge, Eulito Bautista, and Evangeline Sibayan.

The project was funded by the Los Baños-based Philippine Council for Agriculture, Forestry and Natural Resources Research and Development (PCARRD).

The gasifier engine, as reported by Ofie Domingo of PCARRD, can run continuously for eight to 10 hours using gas from rice hull (ipa) coming from a single reactor. This can be done by alternately switching the fuel – from fossil fuel oil to rice hull-gas during all unloading and refining of the reactor.

The gasifier-engine was tested in farmers’ fields in San Fabian, Sto. Domingo, Nueva Ecija, and in Barangay Nambalan, Sta. Ignacia, Tarlac, with farmers witnessing the demonstrations.

Eight kilograms (almost one sack of rice hull) was needed for every hour of operation or 30 kg for almost four hours of operation.

The gasifier entails a capital of P22,000. If it is used in 10 to 30 hectares per year, saving in fuel costs can be more than P26,300. The internal rate of return is more than 97 percent with a payback period of less than a year.

The breakthrough is considered significant considering that rice hulls are only burned by farmers to dispose them.

As per Engr. Alda’s computation, a ton of rice hull is equivalent to 400 liters of gasoline.

The Philippines produces two million tons of rice hulls every year. If these are tapped as energy sources, 800 million liters of gasoline can be saved every year. – Rudy Fernandez