Saving the harvests of farmers can be done without harming the environment. This is possible with the use of mechanical dryers equipped with biomass furnace.

BPRE developed two kinds of furnaces that use biomass fuels or agricultural wastes such as rice hull and corncobs. The first one is the biomass-fed furnace or heater system designed by Ruben E. Manalabe. The second one is the BPRE multi-fuel biomass furnace developed by Manolito C. Bulaong.

Both technologies offer optimized use of mechanical dryers without depending too much on non-renewable energy sources like gasoline and kerosene. Both as well have special features that make them environment-friendly as well as user-friendly.


Biomass-fed furnace/Heater system


Director Manalabe developed the technology as an environment-friendly solution to operate mechanical dryers without the high cost of diesel or kerosene.

`Different furnaces have been developed both locally and abroad specifically to use rice hull as fuel to provide cheaper source of heat for mechanical dryers. However, these designs have not been widely adopted because they are not convenient to use, they require constant user attention and they could not maintain a constant heat output. Thus, there is the need to improve the design and ensure wider adoption and use,` Manalabe claimed.

The technology is considered a two-in-one machine. It does not only provide heat but also produce carbonized rice hull, which is good as organic fertilizer, as microbial inoculants and as feed additive.

The furnace has a simple and compact design with four major components namely, a combustion chamber, a heat exchanger, a fly ash scrubber and a temperature controller. It is fully automatic that it can synchronize fuel feeding and ash discharge. It as well emits clean air output with its fly ash scrubber.

The technology can be retrofitted to a 1- or 2-batch recirculating dryer and provide drying temperature of 60°C to 70°C.

Adapters of the technology like the Sorsogon Integrated Development Cooperative (SIDECO) shared that the furnace technology has reduced their spending on kerosene fuel and helped them dispose their farm wastes in a productive way.

`Nung ipinaalam sa amin na may ganitong technology, nagka-interes kami para masubukan` (When we were informed that there is a technology like this, we signified interest in trying it), Anthony Bravo, chief operation officer of SIDECO shared.

Mr. Bravo further said that their cooperative is looking forward for other technologies that would ease their operations in their province.


BPRE multi-fuel biomass furnace


Dr. Bulaong developed the user-friendly furnace as an alternative heat source for mechanical dryers in corn-producing areas. He designed it as a very flexible technology that can use not only rice hull but also other waste materials like corncobs, wood chips and saw dusts.

`Mainly the furnace is distinct from other furnaces because of three things. One, it is simple in design. Second, it is made of durable and quality-certified materials. Refractory bricks and high quality fire tubes were used. Lastly, it is very convenient to operate because it has an automatic fuel feeder and ash discharge system, and it uses a proportional integral derivative (PID) type temperature controller,` Bulaong said.

The furnace can supply clean hot air for up to 283 m3/min air flow rate at its maximum temperature of 90ºC.

Bulaong further related that the furnace can be retrofitted to LSU type mechanical dryer and a flatbed dryer. It can provide an average drying air temperature of 60°C to 75°C at airflow rates of 231m3/min. Drying time range from six to eight hours/batch at corn initial moisture content of 23 to 30 percent.

The potentials of the furnace are based on the results of the pilot tests conducted under the project, Sustainability of Community-based Drying Center Established as Public Investment.

Corn grower and traders like Antonio Barrientos of Maddela, Quirino and Bello Miguel of Benito Soliven, Isabela shared their experiences in using the multi-fuel biomass furnace.

`The furnace is more economical to use because we are using rice hull as fuel instead of diesel. Salamat sa BPRE natutunan naming ang paggamit ng mechanical dryer at furnace` (Thanks to BPRE we have learned to use mechanical dryer and furnace), Barrientos related.

`Maganda ang performance ng furnace. Di ko na kailangang gumastos kasi ang panggatong ay corn cobs at kahoy. Ang binabayaran ko lang ay electricity na nagpapatakbo sa dryer` (The performance of the furnace is good. I don't need to spend much on fuel because it uses corn cobs and wood. I only spend on electricity to run the dryer.), Miguel as well disclosed.

Both technologies show significant increase in the use of mechanical dryers and positive economic effect in the part of the users. Users of both technologies acknowledged the importance and opportunities a biomass furnace could do in their business operations.