Biological treatment of dairy wastewater was investigated using a laboratory scale aerobic sequencing batch flexible fibre biofilm reactor (SBFFBR). The SBFFBR system was modified from a typical sequencing batch reactor system by using eight flexible fibre bundles with a very high specific surface area, which served as support for microorganisms. The reactor was operated under different influent chemical oxygen demand (COD) concentrations (610, 2041 and 4382 mg l −1 ) and constant hydraulic retention times of 1.6 days. The results have shown successful applicability of the SBFFBR system to treat this dairy wastewater. High COD removal efficiencies between 89.7 and 97% were achieved at average organic loading rates of 0.4 and 2.74 kg COD m −3 d −1 , respectively.  2009 Curtin

Milk processing industries consume significant volumes of sustainable water during processing and operating steps to meet hygienic requirements. Therefore, such industries are recognized as a potential source for producing large volume of contaminated water which generally contains biodegradable matters, and are subsequently suitable to be biologically treated. Based on this, many researchers have been moving towards milk processing wastewater (MPW) treatment via biological approaches. In present study, the performance of a single stage flexible fibre biofilm reactor (SS-FFBR) in mitigation of organic loading of the MPW was assessed. The performance of SS-FFBR in terms of the biological treatment was statistically modelled and analysed in terms of HRT and COD in by employing response surface methodology (RSM). From the results, it is clear increase in HRT and decrease in the COD in led to incrementing the COD removal percentage. In addition, a significant mutual interaction occurs between the variables and other responses. The optimum removal was reported at an HRT of 8 h and COD in of 3922 mg/L corresponded to high OLR of 11.67 kg COD/m 3 .d. The experimental results were in good agreement with model prediction.

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In the thermal spraying process, the porosity of ceramic coatings contributes directly to the efficiency of the thermal insulation. The size, shape, and distribution of the pores determine the level of both thermal and sintering resistance. In this work, three different atmospheric plasma sprayed (APS) alumina coatings were fabricated with the same spraying parameters using alumina powders with fine, medium, and coarse particle size. The microstructure of the obtained coatings was analyzed regarding the obtained total porosity, pore size, and pore shape. It was found that it is expedient to divide the pore size range into fine, medium, and large sizes. The shape was characterized with regard to the circularity aspect. In this way, all types of cracks can be considered as oblate pores and were included in the calculation of the total porosity. In the case of using fine feedstock powder, the densest coatings were produced among all coatings, and the fraction of fine pores and cracks are thereby substantially higher. However, the total porosity increases with increasing feedstock powder size. A connection was also made between thermal insulation and porosity fraction which includes fine pores and cracks.