The Japanese have been trying to implement a method of converting refuse organic waste into usable fuel for some time now, but have encountered formidable barriers in their path. Their refuse-derived fuel (RDF) is produced from raw garbage, an adhesive, and lime in pellet form. However, the heat output of the RDF is very low compared to traditional fuels such as coal. In most cases, oil or other combustibles are combined with the RDF for improved usage. Plants producing the RDF also run the risk of fires from methane build-up and increased cost to recover the lime in the ash created during the process. With these barriers, RDF plants have not been as successful breaking into the market as possible.
Takeshi Sako and a group of fellow researchers are looking to change this. They claim to have found a way to create fuel from discarded plastic containers and the non-edible portions of agricultural goods. Their process involves extreme temperature and pressure, mimicking Mother Nature’s own process. Sako mixes the waste products with superheated water at two hundred degrees Celsius and at a pressure roughly twenty times normal atmospheric pressure. The organic materials bond to broken down plastic particles to form a powdered fuel which can be compressed into pellets.
The main benefit of Sako’s product over RDF lies in its heat output. During trials, Sako recorded values of 6,250 to 7,000 kilocalories per kilogram; the same range as coal. Also, the Sako product, when burned, produces no sulfur dioxide and the output of nitrogen oxide and dioxins is well below government standards for power plants. Sako and fellow researchers hope to have their method put into practical use within three years.
This new Sako fuel holds promise for the entire world, but especially to the cement industry. As a major greenhouse gas emitter, the cement industry is spending billions on pollution controls and alternative fuels. Sako’s research is a windfall for the industry, as garbage is the one by-product of civilization that will never cease to be produced. By harnessing this resource and time, companies will be able to expand their horizons for a healthier and “greener” bottom line.
Turning waste into fuel, whether it be from a landfill or wastewater treatment plant, make sense from the points of conservation and recycling of resources.