Pre-treatment of sugar cane : Final report JCU030

Abstract

This project developed a customised microwave applicator for the pre-treatment of sugar cane. Three undergraduate Engineering students investigated the optimisation of microwave treatment, mechanical and chemical properties. The microwave treatment resulted steam, popping or burning of the sugar cane depending on the power and treatment time. The investigations substantiated that the microwave treatment of the sugar cane soften the strength of the sugar cane. Young’s modulus, yield strength and ultimate strength in compressive state were measured as functions of different microwave-treatment parameters. Results have demonstrated that microwave treatment has resulted in up to an 80% reduction in cane billet mechanical properties including yield strength, ultimate strength, and Young’s modulus. Microwave treatment significantly reduced the compressive strength of sugar cane making it easier to crush and as result around 60% energy can be saved during the crushing process.

Experiments were conducted to find the time required to reach equilibrium, which is assumed when the brix% has not changed in a period of 30 minutes. Colour, purity, corrected brix, corrected pol and CCS were then determined in duplicate for each sample at the South Johnstone Sugar Mill (SJSM) laboratory. The results from the SJSM laboratory analysis shows that there is little difference between the two microwave treatment conditions tested in terms of final Colour, purity, corrected brix, corrected pol and CCS. For all three variables the p-Value is greater than 0.05, this is evidence to accept the null hypothesis suggesting that differences between the two microwave conditions are statistically insignificant. This study confirmed that 5 minutes of microwave treatment has no statistically significant impact on any of the key variables that determine the quality of sugar cane juice. Therefore there is no potential consequence in using microwave to pre-treatment the sugar cane before cru