DEVELOPMENT OF A SCREW PRESS BRIQUETTE MAKING MACHINE

Abstract

Briquetting is the process in which low density biomass residues are converted into high density and energy concentrated fuel briquettes. Briquettes are widely used for any thermal application. These include; house warming, steam generation in boilers, flammable material in brick kilns, paper mills, chemical plants, distilleries, food processing houses and oil mills. Mild steel was used in fabricating majority of parts of the machine due to its strength, rigidity, machinabilty, availability and cost implication. Some of components of the machine developed includes; machine frame, hopper, bearing, screw/shaft, screw conveyor casing, briquetting die/mould, compression plate, pressure gauge, briquette collection table, belt, pulley and a 2 horsepower electric motor. The electric motor provided the needed low speed of 600rev/min required to drive the shaft and to gently force biomass material into the briquetting die where compression took place .In evaluating the performance of the machine developed, briquettes were produced using sawdust as the raw material. The sawdust was pulverized to increase the surface area and to enhance binding efficiency. The pulverized sawdust was thoroughly mixed with water and cassava starch which acts as the binder. The choice of cassava starch was based on the fact that it is cheap, easily accessible and readily available and it burns with less smoke when used in small quantity. The prepared material was fed in through the hopper and was gently forced into the briquetting die by the rotating shaft before compression took place. The compression level was read through the pressure gauge firmly welded to the back of the compression plate. Briquettes of 46 mm in diameter, 200 mm in length and internal hole of diameter 10 mm were produced from the machine developed and were sundried. The briquette making machine developed is capable of producing briquettes from any biomass waste.