Evaluation of energy conservation by second-stage drying

Second-stage drying is a process in which latent heat from a dry kiln is ca ptured and used to heat a smaller secondary kiln. Three second-stage chambe rs were constructed and three different heat exchanger profiles were tested . Twenty tests were run with primary kiln conditions of 121 degreesC dry bu lb and 100 degreesC wet bulb. Equations were developed that predicted the a mount of attainable heat based on the heat exchanger design and the tempera ture of the second-stage chamber. Results indicate that this technology is effective at capturing the latent heat given up by the condensation of wate r.