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Lactic acid fermentation has been continuously investigated because of many industrial applications and almost all studies have been carried out with glucose or lactose but very few studies have been done using cassava hydrolysis. It would be a big advantage to use starch or pre-treated starch instead of other carbon sources from their economic point of view. Thus, the aim of this study was to demonstrate a fermentation process, which would economically produce lactic acid from inexpensive carbon source. This production was carried out in two phases. In the first, the spores of lactobacillus casei were inoculated to the growth medium. After immobilization of enough cells on carbon fibres, the medium was changed to production medium to enhance the production of lactic acid instead of biomass. Samples were taken at specific time interval and analyzed. It was found that a feed concentration of 25 g/l had the highest conversion of 97% at D = 0.47 hr-1 yielding maximum productivity of 11.40 g/lh of lactic acid, 8 hours after start up. [ABSTRACT FROM AUTHOR]

This paper presents the recently developed extraction circuit to produce high quality products with low chromatite levels whilst maintaining sustainable PGMs recovery. This was accomplished by installing a chrome extraction plant in the middle of the flotation circuit in order to benefit the increase in PGMs recovery from secondary circuit by lower tonnage to the mill, hence more residence time and better grinding results. The results obtained indicate that the installation of chrome plant in the middle of flotation circuit reduced the amount of chrome in the final PGM's product and PGMs entrained in the tails can be recovered. Low chromites levels of less than 2.2% whilst maintaining PGMs recovery at 80% were obtained. The results also show that the chemical grades of 43.52% Cr2O3 were obtained which fall within the customers' specifications. [ABSTRACT FROM AUTHOR]

The deviations of glass quality from specifications, which are caused by batch losses during transportation and variations in the starting raw materials, have been investigated. In this study, 20 samples were collected from the production line and characterized in terms of XRF analysis, density and cord measurement. The results from the XRF analysis showed considerable deviations in raw materials components from set points and also confirmed changes in the time for the glass to set in the forming stage. Considerably low density shifts were noted and the cord rating remained unchanged due to the undersized quantities of raw materials lost per batch through the system. The varied compositions of raw materials resulted in exaggerated shifts in density, suggesting alterations in the properties of glass. The shift in glass properties results in difficulties during the melting and bottle formation processes, and is potentially dangerous as the containers formed from this glass could shutter under pressure when filled with product. [ABSTRACT FROM AUTHOR]