Guided Design of Heating and Cooling Mains for Lower Water and Energy Consumption and Increased Efficiency

摘要

Water cooling and water heating is an important source of energy consumption,rnaccounting for more than 20% of all energy consumption in manufacturing industry. Itrnis clear that the development of heat recycling schemes and better structural design canrnallow reaching significant savings. It is also known from power generation and from thernbulk chemicals production that the cooling water systems are generally designed with arnset of heat exchangers arranged in parallel. This arrangement results in higher coolingrnwater flowrate and low cooling water return temperature thus reducing cooling towersrnefficiency. This indicates the importance of the system structure, the possibility ofrnmixing of heating or cooling water; recycling and reuse of heating and coolingrnresources and finally the importance of distribution of the driving forces to heat transfer.rnThis paper reports a technique for grassroot design of centralised cooling and heatingrnwater system for water and wastewater minimization which incorporates thernperformances of the cooling/heating providers involved. The study focuses onrncooling/heating systems consisting of multiple chillers and/or boilers that supply arncommon set of heat exchangers. The paper takes a conceptual approach to the statedrnproblems, but traces the way for exact solution using the superstructure basedrnmathematical approach (formulating the problem). It explores cooling/heating waterrnreuse opportunity and predicts thermal performance of thermal systems involved.