Within the framework of this thesis waste heat recovery for industrial ventilation systems is examined with respect to technical and economical aspects. The goal of this paper is to be able to distinguish between waste heat recovery technologies which are applicable for the considered process air technology systems and which are not. These considered systems are industrial ventilation systems with exhaust air temperature between 25 °C and 50 °C. They do not only transport fresh air into a production hall but also filter the emissions of the exhaust gas and are therefore classified as process air technology systems. Before one can make a point whether a waste heat recovery system is applicable or not, every technology has to be investigated in detail and has to undergo an assessment scheme in a first step. Only those waste heat recovery systems which score well in the assessment scheme will be further considered. In the following steps they are being examined regarding their technological and economical criteria based on three reference facilities. So from a large number of heat recovery systems only few are classified as suitable for the requested application considering both technical and economical factors. One of the results is that it is not advisable to make a wholesale judgment for all industrial ventilation systems. There are rather some waste heat recovery systems which are more applicable than others and there are those that match under certain circumstances. However there are some waste heat recovery systems that can be quite definitely defined as not applicable for the requested industrial ventilation systems. Some examples for suitable technologies are the thermal wheel, the plate heat exchanger and for some condition also the technology of indirect evaporative cooling.