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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]

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]

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]

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]

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]

Carbon capture and storage (CCS) techniques are considered as one of the promising approaches to reduce carbon dioxide (CO2) emissions from fossil fuel based power generation, which still accounts for a significant portion of greenhouse gas emissions in the world. CCS technology can be used to mitigate greenhouse gas emissions, with the additional advantage that it allows continuing use reliable and inexpensive fossil fuels. However, CCS retrofit entails major capital costs as well as a reduction of overall thermal efficiency and power output. Thus, it is essential for planning purposes to implement the minimal extent of CCS retrofit while meeting the specified carbon emission limits for the power sector. At the same time, it is necessary to plan for compensatory power generation capacity to offset energy losses resulting from CCS retrofit. In this paper, an algebraic targeting technique is presented for planning of grid-wide CCS retrofits in the power generation sector with compensatory power. The targeting technique is developed based on pinch analysis. In addition, the proposed methodologies are illustrated through case studies based on grid data in India and the Philippines. Sensitivity analysis is carried out to determine the suitable CCS technology and compensatory power source which satisfy emission limits. [ABSTRACT FROM AUTHOR]

Synthesis of distributed waste treatment systems has been extensively researched on in the past decades. Although the use of centralised treatment systems is widespread in the process industries, distributed treatment systems are proven to be superior to the former, particularly in terms of cost effectiveness. In this work, a recent-developed graphical targeting technique is extended to determine the minimum treatment flowrate for a single-contaminant system with multiple distributed effluent treatment units. Treatment units of fixed outlet concentration and removal ratio types are considered. Apart from locating the minimum treatment flowrate, additional constraints on maximum inlet concentration and specified regulatory limit are also considered in this work. In addition, the targeting technique is extended for cases with multiple treatment units and two-contaminant system. Case studies were solved to illustrate the proposed approach. [ABSTRACT FROM AUTHOR]