1 DESIGN OF HEAT EXCHANGER FOR WASTE HEAT RECOVERY FROM PRODUCER GAS DR. MADHUKAR S. TANDALE Dr. Babasaheb Ambedkar Technological University, Lonere, Raigad, INDIA tandale1@yahoo.com SANDEEP M. JOSHI * MES PIITEMSR, New Panvel, Mumbai, INDIA smjoshi16@yahoo.co.in Abstract: - An innovative Pancake type heat exchanger is designed for a particular process industry. A new arrangement for flow of hot and cold fluids is employed for design—hot fluid flows in axial path while the cold fluid flows in a spiral path. To assess the performance of the prototype, its model is suitably designed and fabricated so as to perform experimental tests. Also, the design is conveniently programmed to conduct simulation tests on computer. Overall Heat Transfer Coefficient is taken as the measure of performance for comparing experimental results with theoretical values. Percentage accuracy is also estimated. Keywords: - Waste heat recovery, pancake heat exchanger, overall heat transfer coefficient 1 Introduction Heat exchanger is an indispensable component in an industrial system especially in process industry. Lot many commercial designs and types of heat exchangers are available in market for exchange of heat as well as for recovery of waste heat for the process plants. Since it has been a desperate need of the industry to spend less energy and extract maximum work possible out of it, it is this prejudice thought which has accelerated the use of waste heat recovery systems in the industries. Waste heat recovery deals with the extraction of heat from flue gases or other sources, which are otherwise termed as waste, and utilize it for worth production or process. Fig.1 Schematic of possible single process heat recovery energy flow [1] Waste heat recovery benefits can be broadly ________________________ *corresponding author categorized into ‘Direct Benefits’ and ‘Indirect Benefits’. Direct Benefits include—increase in process efficiency arising from reduction in utility consumption & costs and process costs; and Indirect Benefits include—reduction in pollution, equipment size, auxiliary energy consumption etc.[2] Today, various heat exchange systems are available for recovery of waste heat. Selection of the system for a particular use depends on various factors such as heat potential available for recovery, possible use of recovered heat, space available for installing the unit, and of course, cost! The relative increase in heat transfer in spiral tube over a straight tube was noted 40 % higher at Re 2000. This shows that spiral tubes offer better performance as heat exchangers than straight tubes [3]. Also, there are numerous benefits of using spiral tube heat exchanger for process industries, which are listed by Minton [4]. These include— specially suited for flow of small heat loads, particularly effective for laminar flow because laminar flow heat transfer is much higher with spiral tubes, flows can be counter current, no problems associated with differential thermal expansion, compact and easy installation. The smaller length of entire unit is an added advantage of this system as compared to tube-in-tube or coil type heat exchangers. There are few limitations, which are easily overridden by the benefits. 5th WSEAS Int. Conf. on Heat and Mass transfer (HMT'08) , Acapulco, Mexico, January 25-27, 2008 ISSN: 1790-2769 Page 83 of 243 ISBN: 978-960-6766-31-2