Method for integrating low-grade industrial waste heat into district heating network

Low-grade industrial waste heat could be a considerable potential energy source for district heating, on the condition that the heat from different industrial waste heat sources is integrated properly. This study considers a method for integrating low-grade industrial waste heat into a district heating system and focuses on how to improve the outlet temperature of heat-collecting water by optimizing the heat exchange flow for process integration. The pinch analysis concept is considered, and a newly developed thermal theory called entransy analysis is introduced. By using entransy dissipation to describe the energy quality loss during the heat integration, this study analyzes how heat exchange flows influence the final outlet water temperature and attempts to provide an efficient method to optimize the heat exchange flow. Finally, the effectiveness of the proposed methodology is demonstrated by testing it in a project involving the recovery of waste heat from a copper plant for district heating.

[1]  Johan Grievink,et al.  Integrated conceptual design of a robust and reliable waste-heat district heating system , 2007 .

[2]  Chengyun Xin,et al.  VARIATIONAL PRINCIPLES IN HEAT CONDUCTION , 2004 .

[3]  Chengyun Xin,et al.  POTENTIAL CAPACITY DISSIPATION MINIMIZATION AND ENTROPY GENERATION MINIMIZATION IN HEAT CONDUCTION OPTIMIZATION , 2005 .

[4]  Yi Jiang,et al.  A new type of district heating method with co-generation based on absorption heat exchange (co-ah cycle) , 2011 .

[5]  K. L. Heitner,et al.  Industrial waste heat for district heating , 1982 .

[6]  Yi Jiang,et al.  An operation strategy for using a ground heat exchanger system for industrial waste heat storage and extraction , 2014 .

[7]  Paulien M. Herder,et al.  Recycling industrial waste heat for sustainable district heating: a multi-actor perspective , 2009 .

[8]  Mubarak Ebrahim,et al.  Pinch technology: an efficient tool for chemical-plant energy and capital-cost saving , 2000 .

[9]  Lin Sun,et al.  Synthesis of multipass heat exchanger networks based on pinch technology , 2011, Comput. Chem. Eng..

[10]  Yan Li,et al.  A new type of district heating system based on distributed absorption heat pumps , 2011 .

[11]  XinGang Liang,et al.  Entransy—A physical quantity describing heat transfer ability , 2007 .

[12]  Ljubica Matijašević,et al.  Energy recovery by pinch technology , 2002 .

[13]  Yi Jiang,et al.  Industrial waste heat utilization for low temperature district heating , 2013 .

[14]  Predrag Rašković,et al.  Pinch design method in the case of a limited number of process streams , 2009 .