The report summarizes a research project  to identify the condensible components and their representative concentrations in the exhaust from pulp and paper processes (thermal mechanical pulping and drying), industrial metal painting (application and drying) operations and commercial kitchens (restaurants). A major component of the study addressed the corrosion and fouling effects of these exhaust environments on selected air-toair heat exchanger materials through the field installation of coupons in each effluent. Chemical analyses of exhaust samples and the residual material removed from the exposed coupons comprised one phase of laboratory investigation while the metallurgical examination of each corrosion coupon paralleled the chemical program.

The metallurgical examination determined the extent of corrosion and fouling of samples by visual inspection and by suitable solvents to remove condensate. Metallorgraphic examinations were carried out to determine the type of corrosion process involved - pitting, and inter granular corrosion. Corrosion products were identified by X-ray diffraction. Exhaust samples of some environments were collected and analysed to determine the cause of corrosion and fouling and supplement the identification of condensibles in each effluent.

The relative heat transfer characteristics of fouled coupons were determined which usually indicated a greater thermal conductance than the clear material.