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To achieve carbon neutrality by 2050, Malaysian government has identified green hydrogen (H2) as one of the potential energy sources. However, the high production cost of green H2 and technical complications of H2 storage conditions for distribution undermines the strategic framework of the H2 roadmap in Malaysia. The lack of investments in pre-requisite support infrastructure for the H2 production, conversion, and storage technologies impedes the progress of the H2 economy in Malaysia. Recently, ammonia (NH3) has emerged as a promising carbon-free energy carrier due to its increased ease and safety during transportation and storage. There is limited literature regarding the inclusion of an NH3 synthesis and storage loop in green H2 supply chains. This research proposes a systematic approach for the techno-economic evaluation of green H2 supply chains with green NH3 as a clean energy carrier of H2 storage and distribution. A superstructure-based mathematical optimisation model was developed to synthesise the optimum supply chain network configuration for a given optimisation objective. A case study is solved to illustrate the proposed model. [ABSTRACT FROM AUTHOR]

Household products such as dishwasher products and multipurpose cleaners may contain specific chemical ingredients to meet the consumer needs. However, some of the ingredients may result in skin and respiratory irritation. Thus, a systematic methodology to estimate the extent of hazard and risk for consumers’ exposure to the products is needed. In this work, an index-based methodology is presented to estimate the severity of the hazards and risks of the ingredients at during the early stage of product design. Higher score was assigned to the higher potential of hazard and risk, and vice versa. The hazard potential was determined based on hazard classification by the Global Harmonised System (GHS). Risk assessment was performed by considering the Margin of Exposure (MOE) and Risk Characterization Ratio (RCR). To demonstrate the proposed methodology, the dermal and inhalation hazards as well as risks from ingredients used in formulation of liquid detergent were evaluated.

This study assessed the health risk analysis of haze pollution in Pasir Gudang and Larkin. The relationship between health risk and economic effect due to air pollution exposure in Johor is still poorly understood. Therefore, the objective of this study was to analyse the relationship between air pollution and health. Then, the economic impact due to smoke haze on associated outpatients was calculated. Daily morbidity data from 2014 to 2016 for three haze-related illnesses were collected from two health clinics. Data on air quality were obtained at two Continuous Air Quality Monitoring (CAQM) stations in Johor. Health risks for all age categories in the haze periods were higher than those in non-haze periods. The outpatient morbidity cases in health clinics increased with the rising occurrence of smoke haze in Johor Bahru. The average annual economic losses due to the outpatient health impact of haze were valued at RM83,233 and RM107,486 for Pasir Gudang and Larkin, respectively.

Over the years, safety and health effects among consumers due to the exposure of formulated products have been reported. Thus, there is a need for systematic methodologies to assess the safety and health effects of the candidate’s ingredients in the early stages of formulated product design. Therefore, an index-based methodology was proposed to assess the safety and health effects in formulated product design. Product Safety and Health Index (PSHI) highlights the health sub-indexes based on the exposure routes including eye, inhalation, ingestion, and dermal. Each exposure route has its corresponding health sub-indexes that have to be applied. There are also new sub-indexes introduced for ingestion and dermal exposure. A case study on paint formulation was used to illustrate the developed methodology. The results show that the newly proposed index is able to identify hazardous chemical ingredient(s) with its corresponding adverse safety and health effects.

Hydrogen is regarded as the fuel of future by having greater heating value than the conventional fuels and with zero carbon emission. Most of the previous supply chain studies only consider the application of hydrogen as transportation fuel. Taking Johor as a case study, this paper aims to develop a holistic optimization model that exploits the use of hydrogen for vehicle fueling and electricity generation. Oil palm biomass and solar energy are used as the energy sources to produce hydrogen and electricity to satisfy the local energy demand. Through this study, the optimal configuration of hydrogen supply chain in Johor has been identified and the associated cost is found to be 3,644,800 USD/d. [ABSTRACT FROM AUTHOR]

The valorisation of waste is often represented through the form of energy recovery, nutrient reclamation and other by-products. Solid Recovered Fuel (SRF) or Refuse Derived Fuel (RDF) as a solid alternative fuel has shown promising results for waste management and enhancing the energy security. The energy recovered is dependent on the quality of the solid fuel, which is evaluated by several parameters, including the calorific value, the moisture content, the density, the oxygen content and the gas emissions. The parameters varied following different types of wastes, which increase the complexity in producing high quality of solid fuel from a mixture of solid waste. This study aims to compare different mixtures of alternative fuel composed of municipal solid waste (MSW), non-hazardous industrial waste and agricultural waste. The selected wastes have high calorific value (2,601-8,657 cal/g), low moisture content (0.06 - 9.86 %), various density (63 - 910 kg/m³), high carbon (C) of 45 - 67 %, low nitrogen (N) of 0.15 - 2.22 %, low sulphur (S) of 0.01 - 0.80 %, moderate hydrogen (H) of 4.9 - 8.21 % and high oxygen (O) of 25 - 45.5 %. The high C and O content indicated high energy and combustibility, whereas low N and S concentration can reduce the emissions of unwanted gas. The selection of the optimised mixture is based on technical and economic feasibility assessment. The technical score is calculated over seven criteria, including calorific value, moisture content, density, O and gas emissions (COx, NOx, SOx). Based on the assessment on these parameters, the optimum mixture consists of 23.00 % rice straw, 19.52 % wood, 24.58% plastics, 18.43 % cotton stalks, and 14.47 % used tires. The optimum mix has a calorific value of 5,272 cal/g, density of 311 kg/m³, and moisture content of 1.94 %. The analysis demonstrated that mixture with high proportion of plastics, rice, wood and cotton stalk ranked high as preferable alternative fuel. The analysis also showed that the ranking of the alternative fuel decreases following an increase of sludge and olive pomace in the mixture. The proposed selling price of the alternative fuel produced is 135.47 USD/t covering all capital costs and operational and maintenance costs. [ABSTRACT FROM AUTHOR]

Due to increasingly stringent legal requirements and escalating environmental control costs, chemical industries have paid close attention to sustainable development without compromising their economic performance. Thus, chemical industries are in need of systematic tools to conduct sustainability assessments of their process/plant design. In order to avoid making costly retrofits at later stages, assessments during the preliminary design stage should be performed. In this paper, a systematic framework is presented for chemical processes at the preliminary design stage. Gross profit, Health Quotient Index (HQI), Inherent Safety Index (ISI) and the Waste Reduction (WAR) algorithm are used to assess the economic performance, health, safety and environmental impact of the process, respectively. The fuzzy optimization approach is used to analyse the trade-off among the four aspects simultaneously, as they often conflict with each other. Deviation between the solution obtained from mathematical optimization model and process simulator is determined to ensure the validity of the model. To demonstrate the proposed framework, a case study on 1, 4-butanediol production is presented. [ABSTRACT FROM AUTHOR]