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Wastewater treatment (WWT) is a mandatory process to ensure wastewater quality meets legislation requirements and to reduce environmental impacts. Many established WWT technologies are available in the market and the selection of such technologies is usually based on heuristics. However, technologies selected using heuristics may not be able to guarantee optimal economic performance. In this respect, it is important for manufacturing companies to synthesise a WWT process with minimum investment cost while meeting legislation requirements. Most manufacturing companies face issues to achieve this goal. Among these issues, is the fact that part of the investment invested into a WWT process will be lost to waste (sludge cake) generation. The generated waste (sludge cake) will require additional high waste disposal costs. Therefore, to reduce the loss of investment in a WWT process, the waste generation cost and waste disposal cost must be minimised. This can be addressed via Material Flow Cost Accounting (MFCA), a management tool that quantifies material flows across physical and monetary values in a production process. Previous works had adapted the concept of MFCA for prioritisation of waste streams for waste recovery and minimisation of investment cost in processes with revenue streams. Thus, the objective of this paper is to extend the use of MFCA as a preliminary decision-making tool in the selection of WWT technologies with minimum waste generation cost. To illustrate the developed approach, a case study on sago-based WWT process is solved in this work. Based on the results, the synthesised WWT process from the developed model is capable of recovering as much as 93.3 % of the total operating cost back into the manufacturing process while minimising the waste generation cost to 6.7 % of the operating investment cost. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2) has been identified as one of the potential energy carriers for the future. Currently, most H 2 is produced via steam methane reforming (SMR) from non-renewable natural gas. This process produces a large amount of carbon dioxide (CO 2) emissions as a by-product. Therefore, CO 2 capture, utilisation, and storage (CCUS) technologies are typically integrated with conventional H 2 plants to produce cleaner H 2 , known as blue H 2. However, such systems face many challenges, such as high process cost, complex transportation and storage of captured CO 2. This work presents an optimisation-based model to optimise the integration of H 2 processes with CCUS systems to produce blue H 2. The developed model considered different grey H 2 production paths, CO 2 capture technologies, CO 2 transportation, utilisation, and storage, as well as H 2 storage. The model also factors in technology efficiency, cost and overall energy consumption. A case study of scenarios such as minimum annualised cost, minimum energy consumption, and minimum CO 2 production/emissions is solved to illustrate the proposed model. Three optimum blue H 2 production routes were obtained with total annualised cost: Case A1 – Minimum annualised production cost (88,953 MMUSD), Case B1 – Minimum energy consumption (96,632 MMUSD) and Case D – Minimum annualised production cost – CO 2 storage (89,950 MMUSD). • Integration of CO 2 capture, utilisation and storage (CCUS) with hydrogen production systems are costly. • An optimisation-based model to optimise integration of hydrogen production with CCUS. • A case study was explored to optimise the deployment of CCUS for hydrogen production based on scenario. • Each scenario yielded the same hydrogen production and storage choices but differed for CO 2 transport and utilisation/storage. • Decision-making tool to determine optimal strategies have been devised for CCUS integration in hydrogen systems. [ABSTRACT FROM AUTHOR]

This paper presents a novel Computer Aided Molecular Design (CAMD) methodology for the design of solvents with consideration of environmental impact during the extraction and recovery processes. Throughout the years, CAMD techniques have been widely applied to design novel molecules for various applications, especially solvents. Most of the works in this area are only focusing on designing solvents that can achieve its functionality. However, limited works consider safety, health and environmental impacts of the process in which the solvent is applied. In this work, a quantitative assessment of the total environmental burden for solvent recovery process is incorporated into a single stage CAMD framework. The CAMD formulation includes molecular properties that affect the quantitative assessment of the environmental impact of a process. A multi-objective solvent design framework is then solved using Fuzzy Analytic Hierarchy Process (FAHP) weighting approach to design solvents that satisfy various target properties. With this approach, the generated solvents can simultaneously improve the overall environmental characteristic of a process and give a better balance of performance for a set of predefined properties. To illustrate the proposed methodology, a case study on solvent design for residual oil extraction from palm pressed fibre is presented. [ABSTRACT FROM AUTHOR]

This paper presents a novel methodology for solving multi-objective Computer Aided Molecular Design (CAMD) problems. One of the major challenges in multi-objective CAMD problems is the subjectivity involved in assigning the weighting factors to each property that is optimised. It is difficult to define the relative importance of each property in CAMD problems as target properties that belong to different categories cannot be compared on a common scale. It is crucial to solve this issue as distinct solutions will be generated due to different weighting factors of each property. In this work, a systematic framework that combines CAMD and Analytic Hierarchy Process (AHP) is developed to deal with the ambiguities involved in assessing the relative importance weightings of target properties in multi-objective molecular design problem. Through AHP, molecular design problems can be approached as a hierarchical decision structure and different categories of target properties are combined in the same analysis. Besides, AHP has the ability to generate numerical priorities from the subjective knowledge in evaluating the relative importance of properties using pairwise comparison. A case study on solvent design for oil extraction from palm pressed fibre is solved to illustrate the proposed methodology. [ABSTRACT FROM AUTHOR]

A systematic framework for Design Operability and Retrofit Analysis (DORA) is presented. DORA is a framework explicitly analyzing energy system design containing process units functioning at different levels of operability. To express the operability of individual process units, DORA uses inoperability input-output modeling (IIM) approach. Based on IIM, a simple mixed integer linear programming (MILP) model is developed to analyze the impact of individual process unit inoperability on the flexibility of an energy system design. In the case where a design is deemed to possess insufficient flexibility to meet demands, DORA framework subsequently entails a step-by-step guide to debottleneck and retrofit a given design based on benefit-cost ratio (BCR). In this work, the DORA framework is demonstrated using a biomass-based tri-generation system (BTS) case study. As shown in the case study, DORA framework is used to determine whether a BTS facing a drop in individual unit efficiency, would require debottlenecking and retrofitting to increase its energy production. [ABSTRACT FROM AUTHOR]

Palm oil mill effluent (POME) is recognised as one of the effluents which may cause environmental pollution when it is not properly treated. Conventional open pond systems are inefficient in treating POME as they generate and release biogas into the atmosphere, causing greenhouse effects. Number of anaerobic digestion systems were introduced in the market to recover the generated biogas for energy and electricity production. To synthesise an optimal integrated network for the conversion of POME into bio-methane, bio-CH 4 , a systematic screening approach is needed. This work aims to develop a systematic optimisation model for synthesis of a sustainable production system of bio-CH 4 from POME based on economic and environmental performances. As the above-mentioned considerations are conflicting with each other, a multiple-objective optimisation approach (fuzzy optimisation approach) is adopted in the optimisation model to trade-off the objectives. Based on the optimised results for a typical 60 t/h of FFB palm oil mill in Malaysia, Integrated Anaerobic-Aerobic Bioreactor (IAAB) at 45 °C and cryogenic separator are selected to produce 90 wt% of bio-CH 4 from POME. The total GHG emission from the synthesized integrated network is estimated as 2.31 million tons of CO 2 per year with total economic performance of USD 7.24 million per year. • Systematic approach to select an optimal pathway for the conversion of POME into bio-CH4. • Multi-objective optimisation to trade-off economic and environmental performances. • A typical case study in Malaysia is solved to illustrate the proposed approach. • Scenario analysis is performed for different optimisation objectives. [ABSTRACT FROM AUTHOR]

Tri-generation system is a facility which produces heat, power and cooling simultaneously from a single fuel source. In the industry, such system is commonly operated via two strategies; Following Electrical Load (FEL) or Following Thermal Load (FTL). However, these operating strategies may lead to huge amount of energy that is wasted. In this respect, several works have proposed a switching strategy, whereby tri-generation systems would interchange between FEL and FTL modes depending on energy demand. Unfortunately, the design of tri-generation based on this strategy has received limited attention. Besides, tri-generation operations often face challenges in equipment reliability. As tri-generation systems contain a network of interconnected equipment, equipment failures would disrupt the overall performance of a tri-generation system. As such, this work proposes a novel systematic optimisation approach to design a robust tri-generation system which can operate optimally in its operating strategies. In addition, the proposed approach can simultaneously determine type, size and required equipment redundancy (e.g. operating and standby units) of technologies while considering operating strategies in a tri-generation system. A palm biomass-based tri-generation system (BTS) case study is solved to illustrate the proposed approach. [ABSTRACT FROM AUTHOR]

The flexibility of a manufacturing process is defined as its ability to accommodate variations and thus, operate in a stable manner for a range of conditions. The subject of flexibility arises in the space of uncertain design parameters that include volatility of raw materials and products price, variability of feedstock supply, and product demand, etc. In this paper, a flexibility model is developed to assess the capacities of process units in a plant to absorb variations in product demand. The flexibility index is introduced in this work to quantitatively measure the capability of the plant to accommodate to the maximum or minimum changes in the demand of multiple products. This involves determining the region for change in the production portfolio at which the plant still operates feasibly while absorbing tolerances between each product demand. The concept of corner points is adapted which forms a geometric boundary to the region of feasible operation. The region considered accounts for process adjustments made to accommodate the different parameter realizations. Fuzzy optimization is then used to determine the best trade-off between two important objectives of maximizing plant flexibility while simultaneously minimizing the total cost associated with the plant. A case study of a palm oil-based integrated biorefinery is presented to demonstrate the proposed novel approach in a more descriptive manner. [ABSTRACT FROM AUTHOR]

Background: Guidelines and text-book descriptions of the Rinne test advise orienting the tuning fork tines in parallel with the longitudinal axis of the external auditory canal (EAC), presumably to maximise the amplitude of the air conducted sound signal at the ear. Whether the orientation of the tuning fork tines affects the amplitude of the sound signal at the ear in clinical practice has not been previously reported. The present study had two goals: determine if (1) there is clinician variability in tuning fork placement when presenting the air-conduction stimulus during the Rinne test; (2) the orientation of the tuning fork tines, parallel versus perpendicular to the EAC, affects the sound amplitude at the ear. Methods: To assess the variability in performing the Rinne test, the Canadian Society of Otolaryngology - Head and Neck Surgery members were surveyed. The amplitudes of the sound delivered to the tympanic membrane with the activated tuning fork tines held in parallel, and perpendicular to, the longitudinal axis of the EAC were measured using a Knowles Electronics Mannequin for Acoustic Research (KEMAR) with the microphone of a sound level meter inserted in the pinna insert. Results: 47.4 and 44.8 % of 116 survey responders reported placing the fork parallel and perpendicular to the EAC respectively. The sound intensity (sound-pressure level) recorded at the tympanic membrane with the 512 Hz tuning fork tines in parallel with as opposed to perpendicular to the EAC was louder by 2.5 dB (95 % CI: 1.35, 3.65 dB;p< 0.0001) for the fundamental frequency (512 Hz), and by 4.94 dB (95 % CI: 3.10, 6.78 dB; p< 0.0001) and 3.70 dB (95 % CI: 1.62, 5.78 dB;p = .001) for the two harmonic (non-fundamental) frequencies (1 and 3.15 kHz), respectively. The 256 Hz tuning fork in parallel with the EAC as opposed to perpendicular to was louder by 0.83 dB (95 % CI: -0.26, 1.93 dB; p = 0.14) for the fundamental frequency (256 Hz), and by 4.28 dB (95 % CI: 2.65, 5.90 dB; p < 0.001) and 1.93 dB (95 % CI: 0.26, 3.61 dB; p = .02) for the two harmonic frequencies (500 and 4 kHz) respectively. Conclusions: Clinicians vary in their orientation of the tuning fork tines in relation to the EAC when performing the Rinne test. Placement of the tuning fork tines in parallel as opposed to perpendicular to the EAC results in a higher sound amplitude at the level of the tympanic membrane. [ABSTRACT FROM AUTHOR]

In this paper, a systematic approach for synthesising and optimising a symbiotic bioenergy park is presented. A novel stability analysis criterion of the symbiotic bioenergy park is developed based on the concept of incremental investment return analysis. The synthesised symbiotic bioenergy park is stable as long as no partner bears a disproportionate share of additional investment costs relative to benefits gained from cooperation. In case the symbiotic bioenergy park is not stable, re-evaluation (e.g., additional incentives from government, subsidies from high profit companies, etc.) can be conducted amongst all participants. In this work, fuzzy optimisation is adapted to trade-off individual economic interest and stability of each processing plant. The optimised network configuration which achieves the targets with minimum biomass value losses can be determined prior to detailed design. A palm-based symbiotic bioenergy park case study is solved to illustrate the proposed approach. [ABSTRACT FROM AUTHOR]

Chilled water is a common cooling agent used in various industrial, commercial and institutional facilities. In conventional practice, chilled water is distributed via chilled water networks (CHWNs) in parallel configuration to provide required air conditioning and/or equipment cooling in the heating, ventilating and air conditioning (HVAC) system. In this paper, process integration approach based on pinch analysis technique is used to address energy efficiency issues in the CHWN system for grassroots design problem. Graphical and algebraic targeting techniques are developed to identify the minimum chilled water flowrate needed to remove a given amount of heat load from the CHWN. Doing this leads to higher chilled water return temperature and enhanced energy efficiency of the HVAC system. A recent proposed network design technique is extended to synthesize the CHWN in a mixed series/parallel configuration. A novel concept of integrated cooling and chilled water networks (IWN) is also proposed in this work, with its targeting and design techniques presented. Hypothetical examples and an industrial case study are solved to elucidate the proposed approaches. [ABSTRACT FROM AUTHOR]

A biomass-based trigeneration systemproduces heat, power and coolingenergy simultaneously. To synthesize a biomass-based trigenerationsystem, decision makers are required to consider a wide range of technologiesbased on various factors (e.g., capital investment, operating cost,availability and reliability of the technologies, etc.). In addition,both short-term and long-term uncertainties that may arise duringthe course of operations should also be taken into consideration.If not considered at the synthesis stage, uncertainties would preventthe designed energy system from meeting the required energy demandsand cause possible bottlenecks during operation. With such consideration,not all available technologies are economically and operationallysensible. Thus, it is essential to develop a systematic approach tosynthesize a biomass-based trigeneration system with considerationof uncertainties. In this work, a multiperiod optimization approachfor the systematic synthesis of a biomass-based trigeneration systemwith variations in raw material supply and corresponding energy demandis presented. Following the concept of multiperiod optimization approach,the fraction of occurrence for each biomass supply and energy demandscenario is included. Meanwhile, the maximum capacities of each technologythat can operate in all scenarios are determined. In addition, selectionof design capacities based on available sizes in the market is alsoperformed simultaneously. To illustrate the proposed approach, a trigenerationsystem with palm-based biomass as feedstock is solved. [ABSTRACT FROM AUTHOR]

RCNet is a spreadsheet-based software for the synthesis of resource conversation networks (RCNs) for planning the efficient use of material resources (e.g., water, utility gases, solvents) in industrial plants. The software is developed based on the well-established process integration tools, namely pinch analysis and mathematical programming techniques. In the first stage, pinch analysis is used to determine maximum resource conservation targets prior to detailed RCN design. In the second stage, mathematical optimisation is then used to determine the optimal flowrate allocation between process sources and sinks of the RCN, to achieve the performance targets. RCNet is applicable for various industrial applications. To date, no generic software has been developed to handle water minimisation, hydrogen recovery and property integration, which is the main subject of this work. In the developed software, same interface and platform can be used to solve abovementioned problems independently. For illustration, three literature examples on water minimisation, hydrogen recovery and property integration, as well as an industrial case study are solved using RCNet. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a generic approach for the synthesis of heat integrated resource conservation networks (HIRCNs) of the fixed flow rate problem, where process sources linked directly to process sinks without any prior mixing. The mixed integer non-linear program (MINLP) formulation complemented by floating pinch concept was developed to determine the optimum fresh material resources as well as hot and cold energy utilities. The proposed approach is applicable for both concentration- and property-based direct reuse/recycle system with variable operating parameters (i.e. flow rates, temperatures and properties). Three literature case studies are solved to illustrate the proposed approach. [Copyright &y& Elsevier]

Most of the established methods for utility targeting in a heat exchanger network (HEN) are mainly focusing on fixed stream conditions, where the flow rate, heat capacity, supply and target temperatures are fixed. However, in the process industries, the stream conditions (flow rates and temperatures) are not fixed. Therefore, the established HEN targeting methods cannot be directly applied to locate the hot and cold utility targets for HEN problem with varying flow rates and temperatures. To address this issue, a revised floating pinch method which uses binary variables to parameterise the stream locations on the composite curves, is presented in this work to identify the minimum utilities targets. The revised method simplify the earlier version of floating pinch method presented by Duran and Grossmann (1986) by avoiding the non-differentiability in the mathematical program. Two cases, one with fixed parameters while another with temperature-dependent properties and varying operating parameters are solved to illustrate the revised model. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis of heat integratedresource conservation networks (HIRCNs), covering both concentration-and property-based direct reuse/recycle systems. This newly proposedmethod adopts the targeting concept of the insight-based pinch approachwhere the minimum consumption of fresh resources and energy utilitiesis targeted prior to the detailed HIRCN design. Furthermore, thismethod is capable of handling HIRCN problems with varying operatingrange of process parameters (i.e., flow rates, temperatures, and properties).The proposed method is formulated as a mixed integer nonlinear program(MINLP). As the temperature of stream is uncertain, the floating pinchconcept is adopted to identify hot and cold utilities. Besides,a recently developed discretization approach is also used to solvethe MINLP problem. Three literature case studies are solved to illustratethe proposed method. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a novel multiple-cascade automated targeting (MCAT) approach is proposed for determining the maximum economic performance of a gasification-based integrated biorefinery. Since multiple process parameters (i.e., heat input of biomass gasifier, syngas specification for downstream synthesis process, gasification temperature, etc.) should be taken into consideration simultaneously in order to optimize such system, this work extends the previously developed single-cascade automated targeting (SCAT) to allow such problems to be dealt with more effectively. This proposed approach, is based on pinch analysis, and can be used to identify the performance targets based on different optimization objectives prior to detailed design of the integrated biorefinery. An industrial case study is solved to illustrate the approach. [Copyright &y& Elsevier]

Abstract: Synthesis and screening of technology alternatives is a key process-development activity in the process industries. Recently, this has become particularly important for the conceptual design of biorefineries. This work introduces a shortcut method for the synthesis and screening of integrated biorefineries. A structural representation (referred to as the chemical species/conversion operator) is introduced. It is used to track individual chemicals while allowing for the processing of multiple chemicals in processing technologies. The representation is used to embed potential configurations of interest. An optimization approach is developed to screen and determine optimum network configurations for various technology pathways using simple data. The solution to the optimization formulation provides a quick and effective method for screening and interconnecting the technological pathways and to distributing the flows over the network. Case studies are solved to illustrate the applicability of the proposed approach. [Copyright &y& Elsevier]

Abstract: Biorefineries are processing facilities that convert biomass into value-added products such as biofuels, specialty chemicals, and pharmaceuticals. Integrated biorefineries which consist of various processing facilities (e.g., digestion, fermentation, pyrolysis, gasification, etc.) have been proposed in order to enhance the energy efficiency and material recovery. This work presents an optimisation-based, automated targeting procedure to determine the maximum biofuel production and revenue levels in an integrated biorefinery. The approach is based on pinch analysis and allows targets to be determined prior to detailed design of the biorefinery flowsheet. A hypothetical case study is shown to illustrate the proposed approach. [Copyright &y& Elsevier]

Abstract: Resource conservation networks (RCNs) are among the most effective systems for reducing the consumption of fresh materials and the discharge of waste streams. A typical RCN involves multiple elements of resource pre-treatment, material reuse/recycle, regeneration/interception, and waste treatment for final discharge. Due to the close interactions among these individual elements, simultaneous synthesis of a total RCN is necessary. This paper presents an optimisation-based procedure known as automated targeting technique to locate the minimum resource usage or total cost of a concentration- or property-based total RCNs. This optimisation-based approach provides the same benefits as conventional pinch analysis techniques in yielding various network targets prior to detailed design. Additionally, this approach offers more advantages than the conventional pinch-based techniques through its flexibility in setting an objective function and the ability to handle different impurities/properties for reuse/recycle and waste treatment networks. Furthermore, the concentration-based RCN is treated as the special case of property integration, and solved by the same model. Literature examples are solved to illustrate the proposed approach. [Copyright &y& Elsevier]

Pretreatment is often necessary when the fresh water available to industrial plants is impure, and when some processes are particularly sensitive to contaminants. Partitioning processes such as membrane separation units are often used for such applications. However, the use of pretreatment units adds to capital and operating costs for a water system. Hence, it is of interest to develop design procedures to minimize the cost for such system. This work presents a graphical pinch analysis approach for targeting minimum flowrate of partitioning water pretreatment systems in single component problem. The approach determines how product and reject streams from the treatment unit can be allocated, along with bypassed freshwater, to satisfy multiple process sinks with their respective flowrate and purity requirements. Hypothetical case studies are presented to illustrate the approach, and generalized design principles based on pinch analysis heuristics are drawn from the examples. [ABSTRACT FROM AUTHOR]

Abstract: Resource conservation is an effective way to reduce operation cost and to maintain business sustainability. Most previous works have been restricted to “chemo-centric” or concentration-based systems where the characterisation of the streams and constraints on the process sinks are described in terms of the concentration of pollutants. However, there are many applications in which stream quality is characterised by physical or chemical properties rather than pollutant concentration. In this work, the automated targeting approach originally developed for the synthesis of composition-based resource conservation network is extended for property-based network. In particular, targeting for the property-based networks with process modification and interception processes are addressed. Based on the concept of insight-based targeting approach, the automated targeting technique is formulated as a linear programming (LP) model for which the global optimum is guaranteed if a solution exists. In case(s) where process modification is involved, the automated targeting technique is formulated as a non-linear programming (NLP) model, in which is solved globally by commercial optimisation software. In addition, a new approach for the bilateral property integration problem is also presented in this work. Literature and industrial case studies are solved to illustrate the proposed approach. [Copyright &y& Elsevier]

Abstract: A graphical pinch-based methodology for planning retrofits for carbon capture and storage (CCS) in the power generation sector is presented in this work. CCS is widely seen as one of the essential interim technologies to mitigate greenhouse gas emissions, while still being able to utilize fossil fuels, which are relatively inexpensive and reliable in comparison to inherently low-carbon renewable resources. However, retrofitting power plants for CCS entails major capital costs as well as a reduction of thermal efficiency and power output. Thus, it is essential for planning purposes to implement the minimal extent of CCS retrofit that meets the sectoral carbon footprint targets. At the same time, it is necessary to plan for additional power generation capacity or efficiency enhancements to compensate for energy losses resulting from CCS retrofits. The simple graphical approach used in this paper is designed to determine such targets, and shares the same intuitive, insight-driven characteristics of pinch analysis techniques. A case study is shown to illustrate the methodology. [Copyright &y& Elsevier]

This paper presents a novel superstructure-based optimization model for the synthesis of industrial water networks with partitioning regenerators. Such regenerators function by splitting a contaminated water stream into a regenerated lean stream and a low-quality reject stream. Membrane separation-based processes are examples of these types of regenerators. The optimization model presented in this work integrates a single, centralized partitioning regenerator with a source-sink superstructure under the assumption that the processes within the plant are of the fixed flow rate type. The formulation is non-linear as a result of the presence of bilinear terms in the regenerator balance equations, but global optimal solutions can be found using commercial software The features of the model are illustrated by solving case studies from the literature It is notable from these examples that considerable design flexibility exists in networks of this type, since potentially both the lean and reject streams from the partitioning regenerator can be reused/recycled within the plant. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents new pinch targeting approaches to locate the minimum CO2-neutral and low-carbon sources for energy sector planning. Graphical targeting approach is firstly used to locate minimum consumption of low-carbon source for energy sector planning. A novel automated targeting approach is next presented to determine the optimum allocation of energy sources in a segregate planning scenario where energy targets for different sub-sectors in the planning horizon are located. [Copyright &y& Elsevier]

Process integration techniques have been well established in various areas, which include energy recovery, in-plant material recovery, industrial symbiosis, energy planning, financial management, etc. Such techniques are widely applied in the research community and industrial applications. Synthesising and designing an eco-industrial park via process integration techniques is recognised as one of the most effective strategies to promote sustainable industrial systems. Feasible operating range analysis has been introduced to evaluate and determine the true operating potential of an eco-industrial park coalition without experiencing design and performance limitations. Such tool also acts as a comprehensive decision-making tool for designers to evaluate the performance of an integrated process at different operational states. In this perspective, a novel mixed-integer linear programming model is presented in this work for simultaneous design and integration of multiple processes to form an eco-industrial park. The true potential and performance of the eco-industrial park developed can be assessed at different operational states. To illustrate the proposed approach, an industrial case study on design of eco-industrial park in oil palm industry, which consists of palm oil mill, integrated biogas and wastewater treatment system, palm-based biorefinery, and combined heat and power system, is solved and presented. [Display omitted] • A systematic approach to design and integrate multiple processes simultaneously. • Improves resource efficiency and reduce carbon footprint. • Determine the true potential and performance at different operational states. • A palm-based eco-industrial park case study was presented. [ABSTRACT FROM AUTHOR]

A sustainable agro-industrial value chain is essential for sustained food security. This requires optimised planning of operations and new expansions along the value chain. In this work, a fuzzy-based multi-objective approach is developed for planning sustainable new expansions of agriculture lands. Also, the expansion and capacity of post-harvest and production facilities and operations of logistics in the agro-industrial value chain are optimised. The model is a mixed-integer linear program (MILP) which takes profit, carbon footprint, and water footprint into account during optimisation. The expansion plan is optimised based on the expected increase in the demand for a particular agro-industrial product. To illustrate the proposed model, a palm value chain case study is solved. A scenario with a projected increase in palm oil demand is considered to demonstrate the model. The results for the case study showed a distinctive difference in the expansion strategy compared to single-objective optimisation, exhibiting trade-off between profit and carbon, water footprints. • Optimisation of land use change for agricultural expansions towards reducing environmental impact. • Optimisation of expansion in the downstream units and the logistics in agro-industrial value chain. • Fuzzy optimisation considering profit, carbon emissions and water footprint. • A palm value chain is solved as case study and the results discussed. • 0.0013 tCO 2 will be emitted and 1.84 m3 of water will be consumed per unit of profit. [ABSTRACT FROM AUTHOR]

In any new chemical process development and design, process safety is a critical aspect to be considered besides economic and technical feasibility of the manufacture of the product. A lack of proper hazard assessment during the design phase may later result in accidents with disastrous consequences to workers, the public as well as the environment. Many methods have been introduced to qualitatively and quantitatively assess the safety level of processes. Despite the availability of a large amount of methods, a systematic framework that details guidelines for hazard identification, risk assessment, safety measure design, and safe critical decision-making is still missing. To address this issue, the main objective of this study was to propose a systematic framework that outlines comprehensive guidelines for assessing the safety performance of processes based on information from the piping and instrumentation diagram (P&ID). Apart from proposing the framework, appropriate strategies for minimizing safety hazards and risks are also recommended. In addition, the user is assisted in selecting the most appropriate assessment method according to his or her needs and the scope and constraints of the assessment. A case study is presented to illustrate the application of the proposed framework. [ABSTRACT FROM AUTHOR]

Computer aided molecular design (CAMD) techniques have been implemented to design molecules or mixtures that satisfy a set of desirable target properties as specified by the customers. Molecular physical and thermodynamic properties are often selected as the target properties during the design stage. However, the incorporation of safety and health aspects into CAMD is not strongly emphasised in many design problems. Because of this, many chemical substances available in the market may lead to adverse health impacts following prolonged and repeated exposure. Therefore, the integration of safety and health aspects as design criteria in the existing CAMD methods is of paramount importance. This is to ensure that the synthesised product does not bring harm and health-related hazards to the consumers. In this work, a novel chemical product design methodology has been developed to integrate both safety and health aspects, as well as the target physicochemical properties into a single-stage CAMD framework. The assessment of safety and health parameters are based on the molecular properties that have significant impact on both aspects. Each property is introduced with an index value depending on the degree of potential hazards. Disjunctive programming algorithm is employed to assist in allocating index scores to the molecules depending on their property values. Fuzzy optimisation is applied to optimise two principal design criteria in this work: product target properties and its safety and health performance. A case study on solvent design for gas sweetening process has been carried out to determine the optimal molecule with reasonably low safety and health hazards level, and at the same time, achieves the target properties. [ABSTRACT FROM AUTHOR]

Assessment on sustainability of production pathway is an important step to promote the sustainability features during early process design. The early process design can be divided into three stages, which are research and development (R&D), preliminary engineering and basic engineering. Note that, the assessment frameworks for R&D and preliminary engineering stages have been presented in our previous works. As continuation, a systematic framework for the assessment of chemical production pathway in basic engineering design stage is presented in this work (0105 and 0110). This framework emphasises on the inherent safety, health and environment (SHE) and economic performance (EP) assessment of chemical production pathway, with the integration of fuzzy optimisation approach as the multi-objective analysis tool. Following the proposed assessment framework, selection of pipe size and types of fittings is considered in this framework for improvement of inherent SHE and EP, as those selection criteria are the key design parameters at this design stage. To illustrate the application of the proposed framework, a case study on biodiesel production pathway assessment is presented. [ABSTRACT FROM AUTHOR]

This work presents an optimization-based negotiation framework for plants in an eco-industrial park (EIP). The framework combines the principles of rational allocation of benefits with the consideration of stability and robustness of the coalition to changes in cost assumptions by analyzing its stability threshold. The stability threshold allows stakeholders to make informed managerial decisions concerning the current or future plant interactions in an EIP. The proposed framework is presented via a palm oil eco-industrial park (PEIP) case study consisting of a biomass tri-generation system (BTS), palm-based biorefinery (PBB) and palm oil mill (POM). The results of the case study indicate that the deserving annual cost savings allocation for BTS, PBB and POM are 38% (USD 2,100,000), 14% (USD 800,000) and 48% (USD 2,600,000) of the total annual cost savings respectively. Based on these allocations, the stability analysis determined that the PEIP coalition will stable as long as the symbiosis costs of BTS, PBB and POM fall within 37–46%, 10–30% and 20–25% of their respective raw material costs. Otherwise, the stability of the PEIP coalition is compromised and further action can be taken as stipulated in the proposed framework. [ABSTRACT FROM AUTHOR]

Sago starch is one of the main carbohydrate sources in many South East Asian countries and Papua New Guinea. To produce sago starch, several activities such as plantation, harvesting, starch processing and road transportation are involved in the sago value chain. During the extraction of sago starch from sago palm, a large amount of water is required. The resulting wastewater is often discharged to the environment without proper treatment. In addition, carbon dioxide (CO 2 ) is emitted over the entire value chain. Hence, water footprint (WFP) and carbon footprint (CFP) should be considered in the optimal synthesis of a sustainable sago value chain. In addition, workplace footprint (WPFP), which measures work-related casualties, also needs to be taken into consideration. To balance the economic performance of the value chain with these footprints, a fuzzy multi-footprint optimisation (FMFO) approach is developed in this work. An industrial case study is then solved to illustrate the application of the proposed model. [ABSTRACT FROM AUTHOR]

• The biomass supply chain offers a greener energy alternative to address the global warming issue. • Relationships among operators are important to the feasibility of a biomass supply chain. • Conflict analysis provides a mathematical framework to model relationships among individuals. • Conflict analysis was utilised in supply chain optimisation to capture the effect of the relationship to the supply chain. • Opimal supply chain using conflict analysis implied higher biomass consumption. Many policies have been rolled out to help biomass supply chains reach their greatest contribution to combat climate issues. However, policies are often undermined by the failure to capture the impact of policy on interactions among players in the supply chain. When players in the supply chain have different perspectives toward a given policy, it impacts the way they interact with one another. This was not considered in the existing literature. A conflict analysis approach is applied to evaluate the impact of the supply chain player's relationship on supply chain decisions. Conflict analysis can be incorporated to mathematically model the behaviours of each supply chain player towards specific proposals or policies. To illustrate the effectiveness of the proposed conflict analysis-embedded model, a case study on a biofuel supply chain based in Malaysia is analysed. In this study, players' reactions in the supply chain toward the three proposed government policies (transport subsidy, workforce reduction and production variation) are systematically modelled and used as an input for the supply chain optimisation. A comparison study is shown to benchmark the results obtained with and without conflict analysis. Based on the optimised results, the conflict analysis model called for a higher amount of empty fruit bunch (i.e., 2.7 times higher between empty fruit brunch sources and first layer storage) than the model without conflict analysis. The total cost associated with the supply chain also increased by 77% after relationships among players were considered (USD 4.5 million to USD 8.0 million). The higher cost and material from the model suggested that conflict reduces the effectiveness of material transfer by reducing the chances of successful trade within the supply chain. By foreseeing and considering the inefficiency of a supply chain in a model, policymakers can, therefore, possible to make more sound decisions. The proposed approach with these findings is crucial in notifying the policymakers of the true potential of their policy toward the supply chain. [ABSTRACT FROM AUTHOR]

To reduce reliance on fossil fuel and environmental issues, alternative energy sources such as biomass are vital to be recovered and converted into value-added products. In sago industry, a huge amount of sago biomass (i.e., sago barks and fibres) is generated and discharged to the environment during sago starch extraction process (SSEP). In order to reduce environmental pollutants, the biomass can be utilised as feedstocks for energy, and bioethanol production. Therefore, Part 1 of these articles in series presents a techno-economic analysis to examine the feasibility of sago biomass-based combined heat and power (CHP) system ( Wan et al., 2015a ); and Part 2 is to examine the feasibility of integrated bioethanol production and energy systems. In this part, a conceptual integrated sago-based biorefinery (SBB) is envisioned and analysed based on the bioethanol plant study conducted by the National Renewable Energy Laboratory (NREL). Besides, techno-economic performance as well as environmental performance of this integrated SBB is evaluated via Aspen Plus software and a spreadsheet based yield prediction model. For the performance evaluation, various feedstocks such as sago fibres, barks and combined biomass (fibres and barks) are considered. In addition, techno-economic and environmental performance of the integrated SBB with on-site and off-site enzyme production as well as the impacts of labour cost on the economic performance of the integrated SBB is also evaluated. Based on the evaluation and analysis, the integrated SBB with combined biomass (fibres and barks) has the highest technical, economic and environmental performance amongst the sago biomass. A total of 4.75 t/d of bioethanol and 252 kW/d of electricity are expected to be produced; and reduction of 16.32 tCO 2 equivalent/d of carbon dioxide emission is expected. In addition, the payback period of the integrated SBB with on-site enzyme production and using current available labour from SSEP is estimated as 6.6 years. Based on the analysis, it is noted that enzyme and labour costs are critical cost contributors to the new development of the integrated SBB and hence, a sensitivity analysis on such parameters is performed. [ABSTRACT FROM AUTHOR]

Traditionally, the design of new chemical products for specific applications is done by using a combination of design heuristics, experimental studies and expert judgements. In addition to the conventional methods, chemical products can also be designed by using computer-aided molecular design (CAMD) techniques. Based on CAMD, optimal chemical products can be designed by identifying the molecule with the best properties that correspond with the target functionalities of the product. In general, the optimality of product property (termed as property superiority) is the only factor considered while designing optimal products by using CAMD techniques. However, it is noted that property prediction models are developed with certain accuracy and uncertainties. As the accuracy of property prediction models (termed as property robustness) can affect the effectiveness of CAMD techniques in predicting the product property, the effects of property prediction uncertainty have to be considered while applying CAMD techniques. This paper presents a systematic fuzzy optimisation based molecular design methodology. The methodology is developed for the design of optimum molecules used in chemical processes by considering and optimising both property superiority and robustness. Property superiority is quantified by property optimality. Meanwhile, property robustness is expressed by the standard deviation of the property prediction model, which is a measure of average variation between the experimental data and estimated values of product property using property prediction model. Fuzzy optimisation approach is extended in this work to address and trade off property superiority and robustness simultaneously. Molecular design technique is adapted in this work to identify the optimal molecular structure which satisfies multiple product specification. To illustrate the proposed method, a case study is presented where optimal solution is selected based on how much the solution satisfied the criteria of property superiority and robustness. [ABSTRACT FROM AUTHOR]

Waste recovery has become one of the most important strategies to reduce environmental issues and improve economic performance in industry. Thus, different systematic approaches have been developed for waste recovery. However, most of the developed waste recovery approaches do not account for the hidden cost incurred from various processing steps as a criterion for prioritisation of waste recovery. This aspect can be determined by the concept of material flow cost accounting (MFCA). Hence, in this work, a novel MFCA-based approach is developed for prioritisation of waste recovery with consideration of hidden costs embedded in process streams. Two case studies are solved to illustrate the developed approach. It can be seen that hidden unit cost (HUC), carry-forward cost (CFC), amount and quality of discharged waste are important factors that significantly affect the prioritisation results. The developed approach then balances the trade-off among these factors to determine the minimum total hidden cost (THC) of discharged waste, and thus improve the economic and environmental performances of an industrial process. [ABSTRACT FROM AUTHOR]

The emerging effects of climate change caused by the rise of carbon dioxide (CO 2) and equivalent greenhouse gas (GHG) emissions to the atmosphere have prompted policymakers to revise current emission reduction schemes. One of the schemes is a carbon permit scheme which places a restriction on the CO 2 or equivalent GHG emissions to the atmosphere. However, limited literature explores the effectiveness of sharing carbon permits in an IS system to optimise and reduce waste emissions in a system. Therefore, this research presents an optimisation-based framework for plants in an industrial symbiosis (IS) system with a carbon permit scheme. The critical success factor for an IS system is the collaboration and synergistic possibilities between participating plants within geographical proximity. This paper takes a different approach from the typical physical resource sharing in IS. This research considers carbon permits as a shared resource between the plant operators. The sharing of carbon permits creates a cooperative environment between the plant operators in the IS system. Through this system, cooperative game theory (CGT) was used to determine the fair allocation of profit to each participating plant operator based on their marginal contribution in the IS system. A case study has been implemented for three process plants: palm oil mill (POM), palm oil-based biorefinery (POB) and combine heat power (CHP) plant that are operated under a carbon permit scheme. Results from the base case study illustrates that each plant operator receives an average of 12% higher profit when sharing their carbon permits relative to working individually under the carbon permit scheme. A further analysis has been conducted to investigate the framework′s economic feasibility at different emission cuts. With differing emission cuts, the results indicated plant operators obtained an increase in their profit margin by 25% when working in a coalition relative to working independently. • Sharing of carbon permits in industrial symbiosis system (IS) with cooperative game theory. • Reducing carbon emission in a system through cooperative games. • Sharing of resources for plants that are not within geographical proximity. • Linear mathematical optimisation to reduce emissions and maximise pooled profits. • Plants receive an average of 12% higher profits when sharing their carbon permits. [ABSTRACT FROM AUTHOR]

This paper presents a heuristic framework that can be used for the debottlenecking of a palm oil-based integrated biorefinery with multiple processes and products. In current industrial practice, any individual unit within these systems is generally designed for a required size. Besides, it also takes into account of an additional margin for safety to meet the requirement of the baseline state of the process. In case there is a variation in the quality of the supplied feedstock or an increase for product demand, it becomes necessary to identify the bottleneck process unit in order to handle the new variation and meet all requirements. In response, the system has to be debottlenecked by altering important operating parameters from the baseline state that limits the change. This stage entails formulating and solving a detailed model for this particular process. In this paper, frameworks are presented to aid decision makers to first identify a bottleneck and subsequently debottleneck the process. The frameworks are essentially a guide for design and safety engineers for decision making at conceptual design stage. A design stage palm oil-based integrated biorefinery case study is solved to demonstrate the proposed approach. [ABSTRACT FROM AUTHOR]

Pulp and paper production consumesa large amount of water andsteam. In particular, water is used in brown stock washing system(BSWS) to separate spent white liquor from the pulp stream. The wastewaterstream generated from BSWS, known as black liquor, is a potentialbiomass. In the current practice, black liquor is concentrated andburned in a recovery boiler to produce steam and electricity. However,recent development in an integrated biorefinery offers increased marketabilityin pulp and paper mills through the generation of both bioproductsand bioenergy. It is common practice for steam generated from thecombustion of black liquor to be integrated with pulp and paper millto satisfy its heating demands. Note that the water consumption inBSWS directly affects the quantity and quality of black liquor. Thiswill later affect the potential for steam generation and integrationin pulp and paper mill. Thus, in this work, water and heat integrationis performed for a pulp and paper mill with biorefinery. An integratedpulp and paper biorefinery (IPPB) is proposed which accounts for differentconversion pathways of pulp and paper mill biomass. Apart from combustion,several gasification pathways are considered. A nonlinear program(NLP) is formulated to synthesize an optimum IPPB with maximum resourcesconservation. Sensitivity analysis is then carried out based on themost significant parameters to analyze the robustness of the proposedIPPB. [ABSTRACT FROM AUTHOR]

Abstract: Biofuel is recognised as an important renewable and sustainable energy source to substitute fossil fuel. To date, biofuel has been evolved from first to fourth generation and they are mainly differed in feedstock and production technologies. Along with the evolution, various studies on different sustainability criteria have been conducted. In this review paper, the state of the art of technologies and assessment methods on economic performance, safety, health and environment (SHE) as well as social impact for biofuel production are reviewed. In addition, this review paper also evaluates the typical methodological framework used for systematic assessment during early process design phase. As conclusion, to establish the highest sustainability in biofuel production, continuous research and development on all sustainability-related aspects are very much needed. [Copyright &y& Elsevier]

Generally,synthesis and design of an optimal process is a challengingtask. The procedure includes specifying and optimizing system configurationsin order to achieve a certain aspect, such as maximizing economicperformance, minimizing environmental impact, etc. However, uncertaintiesof the design parameters (e.g., volatility of raw materials and productsprice, variability of feedstock supply and product demand, etc.) mayundermine the effectiveness of such systematic design approaches.In response to this issue, various optimization works have been presentedto address such problems. In this paper, a robust mixed integer linearprogramming (MILP) with input–output model is presented toaid decision-makers in addressing process synthesis problems due touncertainties that arise from variation in feedstock supply and productdemand. This work primarily encompasses multifunctional energy systemsthat can be described by a system of linear equations, which entails“black box” modeling. The robust model helps to determinethe design capacity of each process unit in a flexible network whichinvolves sizing of equipment. This network is assumed to be able tooperate in all uncertain scenarios considered, with a minimum costof the plant. In addition, the intended model also helps to determinethe requirement to operate additional equipment in a plant in thepresence of uncertainties. This is especially true with designs ofplants that are incapable of meeting any increase in demand. Theseaspects of the work are novel and an important contribution as suchanalysis is not available in the literature, to date. Three case studiesthat include a polygeneration plant and palm oil based integratedbiorefinery are presented to demonstrate the proposed novel approachin a more descriptive manner. [ABSTRACT FROM AUTHOR]

Carbon capture and storage (CCS) is a means for reducing carbon dioxide (CO2) emissions from fossil fuel combustion in power generation and industrial processes. It involves the capture of CO2 for subsequent storage in various geological formations. The selection and matching of the power plants and storage sites are often an issue of optimisation due to various constraints, i.e., time of availability, injection rate, and storage capacity limits. In this work, a novel graphical targeting tool based on pinch analysis is proposed to address the planning problem of the storage of captured CO2 from power generating plants into corresponding reservoirs. The main consideration for the problem is the time of availability of the latter, since reservoirs need to be developed prior to CO2 storage. The time limitation is addressed by the graphical technique where time is taken as the governing element in solving the problem. Hypothetical examples are used to elucidate the proposed approach. [ABSTRACT FROM AUTHOR]

Abstract: Multi-functional energy systems such as biorefineries and polygeneration plants are able to efficiently produce product portfolios by taking advantage of inherent opportunities for optimal integration among process units. Thus, such systems provide valuable solutions towards efficient, sustainable and economically viable production of energy, fuels, utilities and commodity chemicals. On the other hand, the high level of interdependency among process units within such industrial plants is also a potential disadvantage, since the inoperability of one process unit propagates upstream and downstream through the process network to affect other operations. This paper presents a simple mixed-integer linear programming (MILP) model for determining optimal process adjustments in multi-functional energy systems as a result of partial inoperability. The methodology assumes that partial or complete inoperability of some of the process units within the plant forces it to operate away from the baseline state that it was originally designed for. For example, such emergency conditions may result from damaged process equipment. The MILP model determines the optimal reallocation of process streams and operating levels of the process units in order to maximise operating profits from the product portfolio. [Copyright &y& Elsevier]

Depletion of fossil fuels and increasing public awareness of environmental issues has stimulated the search for alternative energy sources. Biofuels are recognised as one of the most promising alternatives to fossil fuels, as they can be produced from various types of feedstock. The efficiency and sustainability of biomass-based production can be maximised by producing biofuels along with other valuable coproducts in a "biorefinery". This concept was proposed to make the production of biofuels and biochemicals more economically viable by taking advantage of opportunities for process integration and waste recovery. In this work, a novel hybrid optimisation model that combines superstructure-based optimisation approach and insight-based automated targeting for the synthesis of a sustainable integrated biorefinery is presented. In addition, fuzzy optimisation is also adapted to synthesize such integrated facility with the simultaneous consideration of both economic and environmental performance. Note that the proposed approach is a generic synthesis strategy that can be applied even without detailed modelling of individual processes. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a mathematical model for resource conservation in a palm oil milling process via property integration. The focus is given to the clay bath system for kernel/shell separation based on flotation principle. In the present work, the clay bath separator is considered as a semi-continuous unit with a specific operating period. This is different from previous works where it is simplified as a continuous unit. The design problem can be formulated as a nonlinear program based on a superstructure approach, with the optimization objective that is set to minimize the fresh resource consumption or the operating cost. An illustrative example is solved to demonstrate the proposed model. The results indicate that more than 40% reduction in fresh resource consumption and more than 50% reduction in operating cost can be achieved through material recovery. [Copyright &y& Elsevier]

Abstract: This work presents algebraic targeting techniques for energy sector planning with carbon (CO2) emission and land availability constraints. In general, it is desirable to maximize the use of low- or zero-carbon energy sources to reduce CO2 emission. However, such technologies are either more expensive (as with renewable energy) or more controversial (as in the case of nuclear energy or carbon capture and storage) than conventional fossil fuels. Thus, in many energy planning scenarios, there is some interest in identifying the minimum amount of low- or zero-carbon energy sources needed to meet the national or regional energy demand while maintaining the CO2 emission limits. Via the targeting step of pinch analysis, that quantity can be identified. Besides, another related problem involves the energy planning of biofuel systems in view of land availability constraints, which arises when agricultural resources need to be used for both food and energy production. Algebraic targeting approach of cascade analysis technique that was originally developed for resource conservation network is extended to determine targets or benchmarks for both of these problems. [Copyright &y& Elsevier]

• Extended Douglas's hierarchical approach for biorefinery process synthesis • Various limitations for the synthesis of biorefinery processes are overcome • Additional tasks to assist reaction pathways screening at early design stage • Solid recovery system and material integration are added to the model Synthesis of biorefinery processes have been of great interest in the research community and industrial practitioners for the past two decades. However, there is a lack of systematic insight-based approach for the synthesis of biorefinery processes, especially at the conceptual design level. This paper presents an extension on the systematic hierarchical decomposition approach (commonly known as the "Douglas's hierarchical approach") for the synthesis of biorefinery processes. Note that the Douglas's hierarchical approach was originally developed for the synthesis of conventional chemical processes, and hence has various limitations when it is applied directly for the synthesis of biorefinery processes. These include unknown reaction stoichiometry, wide varieties of biomass feedstock, alternative conversion platforms, uncertain characteristic of biomass feedstock, etc. These challenges are now being addressed in the extensions proposed in this work for biorefinery process synthesis. Besides, additional tasks are included to assist reaction pathways screening at the early stage of design, while solid recovery system and material integration are being considered within the extended approach to maximise resource conservation and to minimise waste generation. The extended Douglas's approach is demonstrated with a case study on the synthesis of palm-based biorefinery processes. [ABSTRACT FROM AUTHOR]

This paper presents an integrated mathematical optimisation approach to synthesise a bioelectricity supply chain network with minimal costs. Detailed economic evaluation was performed to determine the optimum location of centralised or decentralised biomass pre-treatment and power plants. Once the optimum bioelectricity supply chain network is established, input-output modelling of the network is formed. Next, feasible operating range analysis is performed. A palm-based bioelectricity supply chain case study in Malaysia is used to illustrate the proposed approach. Based on the optimised results, a total of 80.90 MW of bioelectricity are generated with an estimated net present value of USD 123.94 million and a payback period of 5 years. Meanwhile, the feasible operating range analysis indicated that the synthesised bioelectricity supply chain network possessed multiple feasible operating ranges; 5.06–10.04 MW, 11.88–36.08 MW and 44.26–101.16 MW. Based on the result, the decision makers can determine the potential of the future bioelectricity projects according to different seasons of supply and demand variations. Image 1 • Integrated approach for bioelectricity supply chain network is presented. • Optimum location of centralised/decentralised technologies is determined. • Feasible operating range analysis is performed for the synthesised network. • Potential for future bioelectricity projects can be determined. [ABSTRACT FROM AUTHOR]

Highlights • Systematic design analysis framework to design combined heat and power systems is proposed. • This framework considers optimistic, pessimistic and cautious risk decision-making. • This framework combines Maximax, Maximin and Minimax Regret Criterion. Abstract Designing a biomass combined heat and power (CHP) system that fulfils uncertain energy demands is a challenging task. This task becomes increasingly complex when historical data and probability distributions are not well defined. This work presents a newly developed decision analysis design framework for biomass CHP system which considers three types of decision-makers, namely optimistic, pessimistic and cautious decision-makers. To illustrate the proposed framework, a palm-based biomass CHP case study is solved. In addition, sensitivity analysis is performed to evaluate the effect of Feed-in Tariff (FiT) rates towards the design of CHP system. The optimum biomass CHP design is then further analysed to determine the “must-have”, “optional” and “must-avoid” equipment within a given range of power demand. The proposed decision analysis design framework enables decision makers to make informed decisions. [ABSTRACT FROM AUTHOR]

A palm oil mill (POM) requires large amounts of steam and electricity to convert fresh fruit bunches (FFBs) into multiple products. During the extraction of crude palm oil (CPO) from FFBs, byproducts such as empty fruit bunch (EFB), palm kernel shell (PKS), etc., and palm oil mill effluent (POME) are generated. In the past decades, palm oil millers have attempted various improvements in milling technologies individually and collectively to enhance extraction efficiency to meet the process and product requirements. However, oil lost in the milling process remains the major issue in POM and leads to huge loss of profit. In order to address such issue, oil recovery technologies were introduced and implemented in the current POM. Nevertheless, such technologies come with additional capital investment and operating costs that may outweigh the profit generated. Therefore, in this work, a systematic approach is presented to synthesize the palm oil milling processes with oil recovery technologies which is technically feasible and economically viable. Multiperiod consideration is also incorporated in the optimization model to address the variation in feedstock availability. [ABSTRACT FROM AUTHOR]