An automated composite table algorithm considering zero liquid discharge possibility in water regeneration–recycle network

In this study, a novel Automated Composite Table Algorithm (ACTA) is developed for targeting the water regeneration–recycle network of single contaminant problem. The ACTA is based on Pinch Analysis, but is automated by taking into consideration the possibility of zero liquid discharge (ZLD) for the water network. In the existing literature, the targeting procedure for ZLD network is based on the graphical tool of Limiting Composite Curve (LCC). However, identification of key parameters (i.e. freshwater, wastewater, regenerated water flowrates, along with pre-regeneration concentrations) is very tedious for highly integrated water network system. The magnification around the turning point of LCC is required to identify the correct pinch points and targeting procedure is done iteratively until the reliable network targets can be determined. These limitations are now overcome by the ACTA, which is an improved version of Composite Table Algorithm that is capable of identifying key parameters algebraically for a given post-regeneration concentration. The newly developed ACTA is capable of handling a wide range of problems including ZLD and non-ZLD network, for both fixed load and fixed flowrate problems

Unified pinch approach for targeting of carbon capture and storage (CCS) systems with multiple time periods and regions

Carbon capture and storage (CCS) is a key technology for the mitigation of industrial carbon dioxide (CO2) emissions. It involves the reduction of emissions from large industrial facilities (i.e., sources) by capturing the CO2 from the exhaust gases and subsequently storing it in appropriate geological storage sites (i.e., sinks) such as depleted oil and/or gas reservoirs, saline aquifers, coal seams and other similar formations. In practice, these sites may not be readily available for storage at the same time or before the sources are operating, which gives rise to a temporal aspect in the planning problem. At the same time, sources and sinks may need to be clustered geographically to minimize the need to transport CO2 over long distances. This work presents an improved pinch analysis based methodology by simultaneously considering injectivity constraint of every sink as well as time of availability of various sources and sinks. Three illustrative case studies are used to demonstrate the applicability of the proposed methodology. The first two case studies illustrate graphical and algebraic variants, while the third case studies shows an extension that involves two distinct geographical regions. (C) 2013 Elsevier Ltd. All rights reserved

A Graphical Approach for Pinch-Based Source-Sink Matching and Sensitivity Analysis in Carbon Capture and Storage Systems

Carbon capture and storage (CCS) is regarded as an important interim technology for the reduction of carbon dioxide (CO2) emissions from large industrial facilities such as power plants and refineries. CCS involves capture of concentrated CO2 streams from point sources (industrial flue gases), followed by subsequent secure storage in an appropriate natural reservoir. Such reservoirs include various geological formations such as depleted oil or gas wells, inaccessible coal seams, and saline aquifers. In practice, such storage sites will have limitations on both CO2 storage capacity and injection rate, subject to geological characteristics. In this work, a graphical approach is proposed for matching multiple CO2 soruces and storage sites (sinks) optimally within a predefined geographical region. The technique is developed on the basis of analogies withe existing graphical pinch analysis approaches for the synthesis of industrial resource conservation networks (RCNs). Generalized principles for optimal CO2 source-sink matching based on pinch analysis insights are discussed in this work. In addition, sensitivity of the system to the uncertainties that occur in CCS planning (e.g., variation of actual injectivity and capacity as well as options for increase or decrease of source lifetime) is considered. Realistic case studies are shown to illustrate these various aspects of methodology

An integrated approach for water minimisation in a PVC manufacturing process

This paper presents a water minimisation study carried out for a polyvinyl chloride (PVC) resins manufacturing plant. Due to the complexity of the mixed batch and continuous polymerisation process, an integrated process integration approach, which consists of process synthesis, analysis and optimisation was used for this work. A simulation model was first developed in a batch process simulation software, SuperPro Designer V6.0, based on the operating condition of a PVC manufacturing process. The batch simulation model captured the essential information needed for a water minimisation study, e.g. process duration, water mass flow, etc. Data extracted from the simulation model was later used in the water minimisation study, utilising the widely established process synthesis technique of water pinch analysis. Two water saving scenarios were presented. Scenario 1 reports a fresh water and wastewater reduction of 28.5 and 90.1% respectively, for the maximum water recovery scheme without water storage system. In Scenario 2, higher fresh water and wastewater reduction are reported at 31.7 and 100% respectively, when water storage tank is installed in the water network