a] Research that has been done so farThis research has been aimed at developing a systematic methodology for the cost-effective reduction of water usage and discharge in pulp and paper plants. As the industry moves towards increased system closure, the build-up of non-process elements (NPEs) leads to serious consequences on the process equipment. In response, this research has achieved the following:• A mathematical model to track water and primary NPEs throughout the pulping process.• Rigorous targeting for water usage and discharge.• A systematic framework for water reduction using mass integration strategies including no/low cost techniques as well as capital-based techniques. • An optimization model for the optimization of allocation, recyc le, and separation of aqueous streams.These mathematical models and allocation strategies have been coded into a computer-aided tool using LINGO programming platform. The program can be readily modified to address a variety of cases. In order to demonstrate the applicability of the developed tools, a case study has been addressed. Furthermore, this research provides a generic framework that can be effectively utilized by industry to develop cost-effective water management strategies and to identify critical research needs.
b] Any preliminary insights on what the study findings suggestThe research has yielded the following useful insights: § Water conception in pulp and paper mills may be reduced by more than 75% while providing value-added solutions (based on the savings in water usage, reduction in wastewater treatment, reduction in chemical usage, and debottlenecking). § As the extent of water recycle increases, small quantities of impurities begin to accumulate. If gone un-resolved, those impurities can lead to the total failure of the process. § There are multiple technologies to remove impurities but they have vastly different economics. Process integration provides a unique and systematic approach to screenings these alternatives and determining the optimal solutions. § Optimum solution strategies involve a combination of in-process modifications and recycle/reuse alternatives.
