MANUFACTURING OF ARTIFICIAL RICE HUSH ASH COARSE AGGREGATE

Abstract

Rice milling industries produce a byproduct named husk. This surrounds the paddy grain. While milling 78% of weight is retained as rice, bran and broken rice. Remaining 22% of paddy weight is received as husk. The fuel for parboiling process in the rice mill is generated by using this husk. During firing process 25% of husk is converted into ash called rice husk ash. In India annually 20 million tons of rice husk ash is produced. When it’s dumped the rice husk ash is causing treat to surrounding environment and causing damage to land. Many ways are being thought for disposing rice husk ash by making commercial use of it. In 1978 Davidovits showed that silicon (Si) and aluminium (Al) present in fly ash, rice husk ash, blast furnace slag reacts with alkaline solutions like NaoH and KOH to produce binders. Since the chemical reaction taking place is polymerization he termed it as ‘Geopolymers’. The polymerization process is a slow process. To fasten the process, activator Na2Sio3 is added. Oligomers or many small molecules are combined into covalently bonded network in geopolymerization. The formation of three dimensional macro molecular structure is believed to be from the contribution of oligomers through geo chemical synthesis. The polymerization process can be applied for commercial production of human needs.