Vienna — The Philippines plans to save nearly one-third of its annual oil import bill through development of the world's first big industrial biomass conversion process using agricultural wastes as raw materials.
The particular importance of this project is that unlike other gasohol or energy-from-plants projects, this one will cut energy costs without diverting valuable sugar or starch crops away from hungry mouths.
The new industry will make use of coconut shells, rice husks, corn cobs, and other cellulose wastes for the production of anhydrous alcohol for blending with gasoline. Such schemes have been made possible through two processes -- one just developed in Canada and the other to be tried for the first in a big way in the Philippines --which promise to avert the threat of conflict between using land for food and using it for energy crops.
Squeezed by the rising oil prices and encouraged by the energy-deficient industrialized world, the developing regions have plunged into the "green petrol" business.
Brazil has led the trend by turning molasses into ethanol fuel. Mexico consumes increasing quantities of cassava in its energy program. The Philippines' "algocas" program is based on sugar cane juice. "Green petrol" plants are going up across Africa.
The young industry offers an enormous potential for meeting future energy needs without a further contribution to the global accumulation of carbon dioxide in the atmosphere. But most energy conversion technologies in use so far require vast quantities of feedstocks that could otherwise be used as food.
The Philippines' 10-year alcogas program is among the most aggressive in Asia. By 1988, the country plans to run 47 distilleries, cutting about 30 percent of the 90 million barrels of oil now imported, creating 340,00 new jobs, and saving $477 million in foreign exchange.
Aided by the United Nations Industrial Development Organization here in Vienna, the Philippines is about to build a $19 million pilot plant to take advantage of new technologies using enzymes for the conversion of cellulose waste into alcohol. There have been so many recent research breakthroughs in the field that the Philippines hopes to launch the first commercial program soon.
It is calculated that the country's agricultural and forestry wastes could supply an energy equivalent of 60 million barrels of oil a year. At present the Philippines depends on imports of crude oil for 95 percent of its total energy consumption.
Cellulose conversion begins with pretreatment of the raw materials, which can range from coffee hulls through rice straw and grass to sawmill wastes. Enzymes then take over, converting the material into a sugary liquid that is fermented and finally distilled into anhydrous alcohol. Waste residues can be evaporated into a syrup for feeding animals, while unconverted cellulose is used as the primary fuel for the plant.
The second approach, developed under the auspices of the National Research Council of Canada, involves a fermentation process using an unconventional yeast. This, too, promises a welcome change in the basic economics of "green petrol" production because it can utilize most agricultural and sawmill wastes. Certain cellulosic crops --especially trees that grow rapidly in dry or marginal land -- might also be used as raw materials.
Poplar, aspen, and eucalyptus, for example, are easy to plant, need little attention until harvesting, require little if any additional water, and do not need replanting after harvesting. Some have attractive leaves for use as forage.
Canadian scientists involved in the development of the process have been approached already by industrialists interested in marketing village-scale fermentation plants in the developing regions.