Pergamon Applied Thermal Engineering Vol. 17, Nos. 8-10, pp. 1015-1034, 1997 c European Communities 1997. Published by Elsevier Science Ltd Printed in Great Britain PII: s13594311(97)oools-5 1359-431 l/97 $17.00 + 0.00 PROCESS INTEGRATION WITH COMBINED HEAT AND POWER (CHP) L. Puigjaner Universitat Politicnica de Catalunya, Chemical Engineering Department, ETSEIB, Diagonal 647, E-08028, Barcelona, Spain Abstract-In this article a process integration methodology is presented which maintains the pinch analysis tradition of targeting followed by design. What is a substantially new approach, is the development and testing of tools for targeting based on the combination of pinch and exergy analysis for combined heat and power systems (CHPS). Both continuous and batch processes are contemplated. The proposed methodology also comprehends appropriate design tools for the simulation, fine-tuning and design optimization of the CHP systems including novel process separation schemes. Industrial applications are presented to substantiate the potential of the emerging technology. 0 European Communities 1997. Published by Elsevier Science Ltd. Keywords-Energy integration, Energy analysis, Process integration, Process design and optimization, INTRODUCTION The two methodologies, Pinch Technology [l] and Exergy Analysis [2], are now available and used widely, but both have limitations if used individually. For example in analysing systems involving heat and power (steam and gas turbines, etc.) pure heat load analysis is insufficient. In contrast, exergy analysis provides a tool for heat and power analysis, though at times, it does not provide clear practical guidelines. Therefore a new approach combining advantages of both is needed. In this work the comprehensive research will be run to maintain the Pinch Analysis tradition of targeting followed by design. What is a substantially new approach, is the development of tools for targeting based on the combination of pinch and exergy analysis for combined heat and power systems. To complete the design, the most promising options identified during targeting should be then further developed into detailed design/optimization. This will make necessary an extended modeling framework, which should cover the continuous, semicontinuous and batch processing stages present in the most general manufacturing systems. An adequate analysis of the detailed plant operations should lead to recipe enhancement resulting in a more rational use of energy. In this sense a detailed subtask modeling platform will cover the analysis and simulation of every utility demand contribution profiles which will make possible hot and cold stream pairs identification and the duration of heat exchange evaluation under multiproduct batch and semicontinuous conditions. There are other options for energy saving and making the industrial processes more efficient in combined heat and power systems: e.g. the application of heat pump for separation, especially for distillation. In contrast to conventional distillation, in heat pump assisted distillation systems the energy passed through the columns does not depreciate entirely but becomes reusable by using; (i) external power, (ii) a part of generated power or (iii) industrial waste heat. The work presented in this article, for the first time, explicitly focuses on economic and environmental benefits of a systematic procedure that contemplates process integration with combined heat and power (CHP). The proposed methodology also comprehends appropriate modeling and design tools for the simulation, fine-tuning and optimization of the CHP systems in both continuous and batch/semicontinuous production schemes. Moreover, systematic separation process selection involving conventional and novel absorption heat pumping considering the combined heat and power systems are also contemplated. 1015