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Global depletion of fossil fuels, growing awareness on the effects of carbon emissions and greenhouse gases and, the need for renewable energy, has increased the attention towards biocoke research and active engagement with various research groups and industrial players. Biocoke production and utilisation is crucial as it contributes to the efficient management of agricultural residue and municipal solid waste. The technologies involved in the biocoke production and the viability of Malaysia's agricultural waste as a feedstock was described in this paper. In addition, the paper provided background information about the biocoke characteristics and the feedstocks that dictate quality. Comparisons of commercial coal coke and biocoke production technologies that may be applicable to Malaysia were also addressed. Moreover, the paper demonstrated the challenges towards Malaysia's biocoke commercialisation despite its viability from biomass feedstocks characteristics, availability, and evidence of calorific value estimations. [ABSTRACT FROM AUTHOR]

In a typical operation of palm oil mill, oil palm residues and palm oil mill effluent (POME) would be produced. While the oil palm residues have been well harnessed as biomass fuel, regional planning of efficient POME utilisation via biogas recovery and upgrading, coupled with possible biogas compressed natural gas (bioCNG) transshipment among the palm oil mill cluster, deserves more research and development. In this study, the objective is to design a modelling tool for optimising the oil palm biomass and POME utilisation pathway as well as bioCNG distribution network for a palm oil mill cluster with maximum simultaneous economic satisfaction level. Fuzzy optimisation approach was applied for this proposed multiple-objective modelling problem. Two case studies were simulated by the developed mathematical tool to examine the economic benefit of POME utilisation pathway in multiple-site palm oil processing complex (POPC) design. Moreover, the impact of feed-in-tariff (FIT) quota variation on POPC and bioCNG transshipment pathway designs was examined. From the simulation, it was found that POME utilisation pathway incorporation had increased the overall annual worth by MYR 15,049,096 per year due to additional revenues from bioCNG and biogas-derived electricity sales as well as utility saving. [ABSTRACT FROM AUTHOR]

There has been growing interest in developing Locally Integrated Energy Sectors (LIES) as a Process (Heat) Integration approach for synergising the industrial thermal energy systems that include renewable energy resources with urban (i.e. civic, residential, business and service complexes). The aim is to enhance the regional energy efficiency and minimise greenhouse gas (including carbon) emissions. However, a comprehensive planning and design framework is crucial at the onset of its development, which is accounting for supply and demand sides, but there have been limited works directed to this scope to date. For the development of such framework, this paper reviews the energy consumption targeting methodologies via Total Site Heat Integration for estimating and designing the capacity of the utility have been reviewed in this work, inclusive of both insight-based Pinch Analysis and mathematical modelling approaches. As a final outcome of the review, suggestions are provided for investigating key factors for integration of industrial, residential, commercial, institutional and service energy systems, maximising the integration and reuse of waste and low potential heat, including renewables to boost sustainability aspects. The review of methodologies for energy system integration is followed by identification of research directions that deserve future attention, refinement and development. [ABSTRACT FROM AUTHOR]

An overview of numerical and mathematical modelling-based distributed generation (DG) system optimisation techniques is presented in this review paper. The objective is to compare different aspects of these two broad classes of DG optimisation techniques, explore their applications, and identify potential research directions from reviewed studies. Introductory descriptions of general electrical power system and DG system are first provided, followed by reviews on renewable resource assessment, load demand analysis, model formulation, and optimisation techniques. In renewable resource assessment model review, uncertain solar and wind energy resources are emphasised whereas applications of forecasting models have been highlighted based on their prediction horizons, computational power requirement, and training data intensity. For DG optimisation framework, (solar, wind and tidal) power generator, energy storage and energy balance models are discussed; in optimisation technique section, both numerical and mathematical modelling optimisation methods are reviewed, analysed and criticised with recommendations for their improvements. In overall, this review provides preliminary guidelines, research gaps and recommendations for developing a better and more user-friendly DG energy planning optimisation tool. [ABSTRACT FROM AUTHOR]

The application of on-grid hybrid power system (HPS) has been effective for harnessing renewable energy resources and ensuring environmental sustainability. A number of algebraic and mathematical modeling approaches have been introduced for the optimisation of on-grid HPS. While algebraic power pinch analysis (PoPA) tools have been developed to enable the selection of cost-effective energy storage technology, the available mathematical modeling approaches have yet to consider the economics and storage system selection in the design of an optimal on-grid HPS. This work presents a mixed-integer linear programming (MILP) for the optimal design of an on-grid HPS with the minimum net present value (NPV) of the overall electricity production cost and the selection of the optimum energy storage technology. Two case studies are presented in this work. In the former, the differences between the developed MILP model and previous methods are highlighted, with sensitivity analysis to investigate the impact of electricity tariff on the on-grid HPS. In the second case study, the developed MILP model was applied to an Eco-Industrial Park (EIP) case study with energy storage technology selection. Lead-acid battery system was found to be the optimal choice due to its low investment requirement. [ABSTRACT FROM AUTHOR]

Global warming issue, which increasingly aggravates over time, necessitates the carbon capture and storage (CCS) technology for its efficient mitigation. Among the major CCS technologies, post-combustion capture is the most established and commonly employed. However, it poses several energy and environment-related problems. As such, research and development of the pre-combustion carbon capture has been conducted to overcome the drawbacks of this conventional approach, and incorporation of ionic liquid (IL) has been increasingly given attention. This paper intends to review the carbon dioxide separation technologies and those related to IL in pre-combustion capture, pre-combustion capture research progress, pilot plant and commercial facilities, as well as modelling approach with special focus on the computer-aided molecular design (CAMD). In the last aspect, emphasis is given to the IL-based UNIFAC model, and key research gaps are identified from the review as general guidelines for the future research work and development in this particular field. [ABSTRACT FROM AUTHOR]

Recently development of computer-aided herbal plant extraction process design has received attention for highly positive future outlook of global herbal industries. Solid-liquid equilibrium (SLE) prediction models comprise a core part of the chemical engineering knowledge base required for the computer-aided process design. In this study, solubility model was developed to predict the solubility of several Orthosiphon stamineus ( Misai Kucing ) phytochemicals (i.e. Sinensetin (SEN), Eupatorin (EUP) and Tetramethylscutellarein (TMF)) in seven solvents, in addition to creating physicochemical property database comprising of melting point temperature, fusion enthalpy, and SLE solubility data. Quantitative Structure-Property Relationship (QSPR) model was developed for fusion enthalpy prediction with absolute average relative deviation (AARD) of 9.33%. For improvement of KT-NIST-UNIFAC model, new subgroups (i.e. aC – CO (fused), aC – O (fused) and C C cyclic – OH) were introduced to better represent the molecular structure of studied flavonoid compounds, and binary interaction parameters were regressed using compiled SLE solubility data. Regressed KT-NIST-UNIFAC model exhibited better performance with AARD of 5.27%. Subsequent simulation study using improved model indicated that acetone was compatible for SEN, EUP, and TMF extraction. [ABSTRACT FROM AUTHOR]

Biogas decentralised energy system is an important technology in developed countries nowadays as one of the energy efficient and eco-friendly techniques for production of bioenergy besides giving significant impact towards reduction of disposed waste volume and greenhouse gas (GHG). The aim of this article is to present a new numerical method, i.e., Gas System Cascading Analysis (GASCA), based on Time Based Pinch Analysis (TBPA) principle. GASCA is capable of targeting the biogas supply-demand chain, as well as optimal capacities of anaerobic digestion (AD) and biogas storage systems for a known total demand profile, with the consideration of energy conversion efficiency for different biogas qualities, charging and discharging efficiencies and losses. In the illustrative case study, the optimal capacity of AD was 4629.52 MJ/h, with initial energy content and maximum energy capacity at biogas storage of 8737.19 MJ/h and 16,988.61 MJ/h. The simulation study also revealed that application of GASCA-optimised biogas energy system could potentially reduce carbon emission by up to 138 t CO 2 eq /d. Moreover, a sensitivity analysis was conducted to examine the impacts of demand variations on biogas system design and regional feedstock selection. [ABSTRACT FROM AUTHOR]