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The mini channel is used widely in industrial applications. The application includes a heat exchanger device, as a part of a cooling system or as a reactant transport channel. However, unlike the pressure drop determination of a piping network, where the loss coefficient values for the bends and fittings are available, similar cannot be done for the mini channel. The loss coefficient values for the channel are rarely determined and reported. The aim of this study is to propose a correlation for the prediction of total pressure drop in a mini channel resulting from the loss coefficient. The results were compared against a numerical simulation. A 42 mm x 50 mm pin type mini channel was used as the sample of the study. The fluid was hydrogen. The flow regime was kept as laminar. The numerical simulation was performed on the whole active area. The correlation was calculated using the loss coefficient values of bends that were determined beforehand. Three correlations were proposed. Statistical values were used as the comparison parameters. Based on the results, an almost similar pressure drop was predicted by correlation III (diff. mean ± SD = 0.005 ± 0.006 kPa). The correlation I and correlation II were not able to predict the expected results at all. The results were from a low Reynolds (range of Re < 200) number. In general, the correlation proposed successfully predicted the pressure drop in a pin-type mini channel using the loss coefficient value of the individual bends.

Dioxins/furans and polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that are lipophilic and toxic in the environment. These contaminants are found in some soils, sediments, feed and food, especially dairy products, meat, fi sh and shellfi sh. The main pathway of human exposure to these pollutants is via food ingestion, estimated at over 95% of the total intake for non-occupationally exposed persons. They last a long time once they enter into the body due to their chemical stability and their lipophilic characteristic whereby they absorb by fat tissue and store in the body. Dioxins and furans contaminants are released through combustion, such as waste incineration, forest fi res, volcanic eruptions and some industrial processes while PCBs are man-made chemicals and has been used because of their stability and low fl ammability as insulating materials in electrical equipment. Waste management is a general acute problem around the world. As one of the developing countries, Malaysia is undergoing economic growth, industrialization and urbanization, thus the proper management of larger quantity of waste being generated is of great concern. For this issue, hazardous waste from industries especially, is becoming a topic of one cannot deny that requires immediate attention. The efforts to reduce the emission of dioxins/furans and PCBs into the environment are being initiated when Malaysia agreed in the Stockholm Convention on Persistent Organic Pollutants in 2002. The toxicity of these contaminants in food/feed, air and sludge samples is monitored routinely. However, intensive measures to prevent the formation of dioxins/furans at the source have not been widely implemented. This paper describes the policies and regulations of dioxins/furans and PCBs in Malaysia. It also addresses the health risk assessment on certain food items and some potential strategic measures are recommended and evaluated.