Optimal Synthesis of Heat-Integrated Water Regeneration Network

Abstract

Optimal synthesis of a heat-integrated water network (HIWN) accounts for the simultaneous conservation of energy and water resources. A significant amount of research work, ranging from complex nonlinear formulations to simplified linear models, has been carried out for the synthesis of HIWNs. The incorporation of interception units leads to additional water and energy conservation but results in nonlinear formulations for heatintegrated water regeneration network (HIWRN) synthesis. This paper proposes a linear mathematical formulation, based on the transshipment model, for the optimization of HIWRNs using distributed interception units. As a result of a reduced number of variables and the absence of nonlinearities, the convergence efficiency is enhanced. The use of distributed interception units allows the regeneration streams to maintain their temperatures, thereby saving a significant amount of energy. A three-stage sequential approach and a simultaneous strategy are proposed for HIWRN synthesis. Although the simultaneous solution strategy provides cost optimal results, the three-stage sequential strategy is preferred in areas dealing with water scarcity and intermittent supply. The solution strategy is applicable to single as well as multiple-contaminant problems for single pass interception units with a fixed outlet and fixed removal ratio (RR). The methodology is demonstrated through literature examples for both types of interception units.

Process Synthesis, Analysis, and Optimization Methodologies toward Chemical Process Sustainability

“…Applying this strategy will involve a better usage of available resources, reducing both carbon and water footprints. 233 Two recent studies confirmed the above, evidencing the effectiveness and advantages of performing these approaches based on resource conservation principles 234 and synchronized material, property, and heat integration for energy-integrated systems. 235 As shown in this review, the available literature on process integration is enormous and has focused on applying resource conservation, cost minimization, and environmental impact mitigation strategies.…”

Sustainable Design Approach for Modeling Bioprocesses from Laboratory toward Commercialization: Optimizing Chitosan Production

“…Waste water streams are taken as inputs to manage water resources from outlet wastewater flows. The water integration was performed by adapting the method proposed by Kamat et al [ 51 ], consisting of an optimization-oriented approach based on interceptor units and water regeneration. The WRN was designed considering an optimization function by minimizing freshwater and the subsequent minimization of the total treatment cost.…”

“…Cost evaluation was measured, considering the total treatment/improvement cost that counts the freshwater ( , regeneration ( , and disposal of wastewater ( costs, as the goal was to improve the sustainability performance of the system. These values were fixed at 1 USD/t, 0.5 USD/t, and 0.5 USD/t, respectively [ 51 ]. For the base case, the economic cost corresponded to the sum of the freshwater supply and wastewater disposal costs.…”