Hon Loong Lam

An algebraic approach to identifying bottlenecks in linear process models of multifunctional energy systems

This paper presents an algebraic approach for identifying bottlenecks in continuous process systems where each process unit is characterized by fixed mass and energy balance relationships. In industrial applications, such a system is designed to produce a particular product portfolio. This is determined from the anticipated products market and is taken as a baseline state. A process plant is designed with the individual process units at the required size to meet the baseline portfolio, and typically additional margin for safety reason is considered. A simple approach to identify the bottlenecks is proposed and the product portfolio is changed by a given fraction relative to the baseline state. A bottleneck occurs when the available excess capacity of a process unit is insufficient to meet the incremental requirement. Two illustrative case studies demonstrate the proposed methodology.

Overview of sustainable biomass supply chain: from concept to modelling

The human dependency on finite fossil fuel has led to its drastic depletion. Along with its detrimental effects on the environment, such practice is now deemed unsustainable. This phenomenon has led to the growth for utilisation of biomass in the production of biofuels, biochemical and other related bioproducts. This waste-to-wealth strategy is no doubt highly beneficial to the society. However, the major challenge in the commercialisation of bioproducts production includes the complex conversion processes and the uncertainty in the supply and sources of biomass. Therefore, efficient supply chain management and optimisation is essential to overcome these barriers and variables that may constrain the development of a competitive and sustainable bioproducts market. This overview provides an extensional definition of biomass-to-bioproducts supply chain and systematically describes the problems and decisions along this chain. It also identifies the characteristics of a sustainable integrated biomass supply chain, and finally presents an overview of biomass supply chain synthesis and optimisation methods. Based on the existing research gap, the key challenges and potential future works are highlighted. This paper will provide readers with an initial point to understand the concept of sustainable biomass supply chain management and the synthesis and optimisation of sustainable biomass supply chain models.

Pinch analysis-based approach to industrial safety risk and environmental management

Pinch Analysis is an established method for enhancing the sustainability of industrial processes via efficient use of various resources. It is based on the principle of target identification followed by subsequent system design aided by a problem decomposition strategy based on the Pinch Point. This approach has recently been extended to apply to a broad range of structurally analogous problems in various domains, such as financial management and carbon-constrained energy planning. In this work, a novel graphical methodology for industrial safety risk and environmental management is proposed. In this method, it is assumed that a set of risk or pollution reduction measures is available, and that each measure is characterized by its implementation cost and the degree of benefit that it delivers. These data are then used to generate a source composite curve. Targeting can then be achieved by shifting this curve relative to a pre-defined sink composite curve, which represents the locus of the plant management’s “willingness to pay,” or budget relative to benefits with respect to risk or pollutant reduction. The methodology is then demonstrated on two case studies. The first case is based on the well-known Bhopal incident, while the second case focuses on the reduction of airborne fluoride emissions from brick firing plant.

Water footprint, water recycling and food-industry supply chains.

Abstract: A review of the food industry water footprint and the water supply chain management is presented. Water demand management, distributed water supply, water supply security, water supply buffering, and the technologies and techniques for water recycling are discussed. Water is widely used in the food industries as an important raw material and as a utility e.g. steam, cooling water, and mass transfer agent. Strict requirements for product quality and the associated hygiene issues in manufacturing contribute to large amounts of high-quality water being consumed by the food processing industry. The adoption of water minimisation techniques can reduce the fresh water demand of water-using processes considerably and, consequently, reduce the amount of effluent generated. Thus, both the costs incurred in the acquisition of fresh water and the costs involved in the treatment of effluent streams are reduced.

Hydrogen from renewable palm kernel shell via enhanced gasification with low carbon dioxide emission.

Hydrogen economy has become more attractive with the energy crises and environmental issues associated with fossil fuel utilization more so with the discovery that hydrogen can be produced from renewable biomass. This provides good prospects to Malaysia that generates abundant palm wastes. Nevertheless, there is still limited knowledge on kinetics parameters for hydrogen production from palm kernel shell (PKS) gasification. Hence, this work aims to develop a mathematical model that is able to describe the kinetics of steam gasification of PKS with in situ CO2 capture while considering tar formation. A mean-squared error minimization approach has been used to estimate the kinetics parameters of the gasification process. Using the calculated kinetics parameters the process efficiencies are profiled with respect to the effect of gasification temperature, steam/biomass ratio and sorbent/biomass ratio. The parametric study indicates that the three variables promote hydrogen production at different degree of influence. This developed model can be further extended to incorporate optimization study on the potential clean production of hydrogen from PKS.

Synthesis of Networks for the Production and Supply of Renewable Energy from Biomass

This paper presents a step towards an integrated approach when synthesizing self-sufficient food-and-energy regional networks and utilising multi-functional crops, which can then be used for food and energy production, dedicated energy crops and low-value agricultural co-products, and waste. For the purpose of analysis, the given region is divided into several zones, which are smaller administratively/economically/geographically integrated areas within the region (Lam et al., 2010). The synthesis of energy production and consumption networks is performed using the superstructural approach, supported by mathematical programming methods. The synthesized networks are comprised of agricultural, pre-processing, processing, and distribution sectors. Economical and environmental evaluation is performed and discussed from optimisation, by employing a mixed-integer nonlinear programming MINLP process synthesizer MIPSYN (Kravanja, 2010).

Synthesis of regional energy supply chain based on palm oil biomass

1 Centre for Process Integration and Intensification, CPI 2 , Faculty of Information Technology, University of Pannonia, Hungary 2 Department of Chemical and Environmental Engineering, University of Nottingham, Malaysia 3 Center of Lipids Engineering Applied Research (CLEAR) Faculty of Chemical & Natural Resources Engineering, Universiti Teknologi Malaysia Jalan Semarak 54100, Kuala Lumpur, Malaysia clear.utm@gmail.com

Overview on economics and technology development of rubber seed utilisation in Southeast Asia

AbstractThis paper overviewed the potential of rubber seed biomass for its various applications and processing technologies. The rubber seed availability and supply are studied and focused on Southeast Asia region. Technologies with rubber seed and rubber seed oil processing are reviewed. Challenges over rubber seed utilisation, e.g. rubber seed biomass availability, labour issue, etc., are raised and discussed. Future developments of rubber seed utilisation, in term of its management trends and supply solutions, are proposed. Rubber seed is gaining attractions for its vast practical applications, as a result of the expansion of rubber industry.

Green supply chain toward sustainable industry development

Recently, there has been growing interest, discussions, and publications regarding green technologies, concepts, and approaches for sustainable design and reduction. Most of these latest developments in this field have been discussed in previous chapters of this book. To link these green technologies from pretreatment to process and delivery, development of a green supply chain is integral. A green supply chain or sustainable network could be defined as the operational management method and optimization approach to reduce the environmental impact along the life cycle of the green product, from the raw material to the end product. These activities should lead to economic growth, environmental protection, and social progress for green technology utilization. To achieve sustainable development, the supply chain does not only focus on transportation/logistic tasks. Special focus must be given to the latest conservation of biomass (mass and energy) used in the process, the possibility of integrating green resources, consideration of industrial symbiosis relationships, and network synthesis with multiobjectives of environmental, technical, economic, safety, and social factors. This chapter provides an overview of such approaches and the method of network synthesis to achieve this goal.

Energy Generation and Carbon Footprint of Waste to Energy: Centralised vs. Distributed Processing

Abstract Waste to Energy (WTE) carries a trade-off between energy generation and the energy spent on collection, transport and treatment. Major performance indicators are cost, Primary Energy Savings (PES), Carbon Footprint (CFP). This presentation analyses the trade-off introducing a new indicator - the Waste Energy Potential Utilisation (WPU). The results indicate that the impact of logistics and energy distribution can be significant, and distributed WTE architectures may be good candidates for optimal solution, subject to further economical and environmental assessment.