Problem statement: In keeping abreast with Malaysia's rapid economic development and to meet the nation's aspiration for an improved quality of life, clean-air legislation limiting industrial and automobile emissions was adopted in 1978. Approach: Yet, to this day, air pollution from both sources still poses a problem for the nation. In order to predict the status of future air quality in Malaysia, a Box-Jenkins ARIMA approach was applied to modeling the time series of monthly maximum 1 h carbon monoxide and nitrogen dioxide concentrations in the east coast states of Peninsular Malaysia, i.e., Terengganu, Pahang and Kelantan, respectively, as well as to a comparison with the representative west coast state represent of Hulu Kelang. Results: In all the states, both carbon monoxide (CO) and Nitrogen dioxide (NO 2 ) concentrations have shown a fairly consistent upward trend since 1996. Nevertheless, the values forecast to 2016 for all states excluding NOx for Hulu Kelang did not exceed the permissible values given by either NAAQS or DOE Malaysia which are 35 and 30 ppm, respectively, at a 1 h average for CO and 0.053 and 0.17 ppm, respectively, for NOx. Conclusion/Recommendations: The forecasting values of each of the concentration parameters are still within a well-conserved condition as they do not exceed the limits of either NAAQS or DOE Malaysia excluding the values for nitrogen dioxide for Hulu Kelang.

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The demanding uses of fossil fuels and their associated environmental footprints are driving researches into renewable energy productions from organic resources and waste. Anaerobic digestion (AD) is an environment-friendly and cost-effective method to produce biogas from biomass. This biogas can be used in power generation, heating systems and in a combined heat and power (CHP) system. Nevertheless, biogas produced from AD contains a big fraction of CO2 and less methane purity. Aspen Plus simulation model was developed for the AD process to produce biogas, highlighting the economical potentials and environmental benefits. Four steps of AD including hydrolysis, acidogenesis, acetogenesis, and methanogenesis with eight reactions were simulated based on the respective stoichiometries. Optimization has involved the search to identify optimum feed flow rate and operating pressure to produce the maximum amount of pure methane. The obtained results showed that optimum feed rate was 0.36 l/day and operating pressure of 3 bar with hydrogen flow of 180 l/day. By using these optimum conditions, maximum amount of methane with high purity was achieved. Otherwise, through biomass natural decomposition, the methane would escape to the atmosphere as one of those significant greenhouse gases.

Water integration among different industries in Eco-Industrial Park brings a promising opportunity in reducing freshwater consumption by implementing industrial symbiosis concept. Mixing of wastewater from industries might be cost-effective, however, it is not the best option for water reuse since different reuse option requires different water qualities and treatment. Thus, wastewater segregation based on the wastewater source and quality is required. This paper reviews the potential wastewater source from the industry and wastewater recovery prior to be reused. The review is based on the literature survey from the industries, suppliers and guidelines. From the survey, wastewater sources that can be recovered for reuse option are water generated as by-product, wastewater from the cleaning operation and utility operation. These wastewater sources cannot be mixed because each source has different types of contaminant content. Appropriate water quality can be achieved through primary, secondary and tertiary treatment. Advance technology such as membranes are efficient to remove non-desirable compounds from wastewater. The treated wastewater can provide a viable solution as an alternative water source to ease water-related stress and wastewater segregation can reduce the burden of the treatment.