Carbonized Rice Hull Has Important Uses
Rice hull “ipa” used to be a big problem of ricemillers, especially in big rice producing areas such as Nueva Ecija and other Central Luzon provinces. It was usually considered a waste product that had to be thrown away. Thus, we used to see big piles of rice husk along the highway. There have been very limited uses for rice hull in the past.
Today, rice husk is becoming increasingly useful as new uses are being popularized. One product that is becoming increasingly popular is the carbonized rice hull, CRH for short. To produce CRH, raw rice hull is burned without air so that it will not turn into ash. CRH is sterile and is free from disease organisms. And that is the reason why Dr. Rene Sumaoang, a microbiologist, has been promoting CRH as an ideal litter for brooding chicks.
There are a number of benefits from using CRH for brooding chicks instead of the usual raw rice hull. Being sterile, CRH minimizes disease contamination. CRH readily absorbs the moisture in the manure so the litter does not get moist and not attractive to flies. When the litter is treated with an enzyme (Biosec) formulated by Dr. Sumaoang, the usual odor from the manure is eliminated. At the same time, the enzymes break down the nutrients found in the manure so that when brooding is over, the litter would have become an organic fertilizer that is ready to use on crops.
Dr. Sumaoang explains that Biosec is a combination of live but immobilized beneficial microorganisms and digestive enzymes. Once applied the beneficial microorganisms multiply very rapidly, inhibiting the growth of disease-causing organisms like E. coli, salmonella and others. The enzymes, on the other hand, break down the food nutrients in the manure into simpler forms that could be readily absorbed by plants.
Dr. Sumaoang observes that chicks grown on CRH litter grow faster and are more uniform in size. They are healthier because CRH does not allow the proliferation of harmful organisms that often cause respiratory diseases and diarrhea.
At the Philippine Rice Research Institute (PhilRice) in Nueva Ecija, there’s a showcase of a pigpen where carbonized rice hull, about one foot deep, serves as flooring instead of the usual cement floor. The pigpen does not have to be washed with water everyday. In fact, it does not get washed for the entire growing period of four months. The manure and urine of the pigs get buried in the carbonized rice hull. The usual foul smell is practically eliminated. And when the pigs attain market size and are sold, the litter is collected and used as organic fertilizer for vegetables, rice and other crops.
CRH is also very useful in rice farming. Twenty bags of CRH combined with organic fertilizer or compost may be applied in one hectare. It could be plowed in during land preparation. This will make the land not only more porous for better plant growth, it will also enable the soil to retain the moisture much longer. Thus, when there is a prolonged dry spell, the rice plants will be able to survive the rainless period longer.
Rice grown in fields enriched with CRH also produce more profuse tillers. This will mean higher yield because there are more stems that will bear fruit.
CRH is also useful in seedbeds for producing rice seedlings. Seedlings grown in beds of CRH are much easier to pull out come transplanting time. The roots don’t get damaged, hence the seedlings get established in the field more readily.
CRH can also be very useful in growing high-value vegetables, including those grown in containers. Combined with compost or topsoil, the resulting growing medium is ideal for producing healthy crops. Radish grown in containers by Dr. Sumaoang’s company produced sizeable roots.
The ornamental horticulture industry could also benefit a lot from the use of CRH. Being sterile, the use of CRH will minimize fungal infection in various ornamental plants. CRH could be combined with compost for germinating expensive seeds. It will also make an ideal material for producing potted ornamentals.
Farmers themselves can easily produce CRH for their own use or for sale. The equipment can be fabricated by them, consisting of a halved steel drum with holes on the side, and a four-foot steel pipe that will serve as chimney. The half drum is turned upside down and the chimney is attached in the middle of the upper end. A few layers of hollow blocks could be installed several feet around the half drum that will contain the raw rice hull to be made into CRH.
With a few pieces of dry wood, fire is started inside the drum. When the fire is stabilized and the pieces of wood are burning, raw rice hull is placed inside the drum and then a big pile is placed all around and way above the drum. The fire inside the drum will gradually burn the raw rice hull. When burning has reached the top of the pile, water is sprinkled to stop the burning so that the burnt rice hull will not turn into ash. Ash is not good for incorporating in the planting medium because it will behave like cement. It will not make the soil porous.