Designing and manufacturing of programmable heat pump dryer and experimental examining at timber drying process

In this thesis, industrial heat pump dryer has been designed and manufactured as energy price has been increasing in recent years. Designed and manufactured dryer experimentally analyzed by timber drying which is important industrial product. Poplar and pine timbers have been dried from the moisture contents of 1.28 kg water/kg dry matter and 0.60 kg water/kg dry matter to 0.15 kg water/kg dry matter in heat pump dryer functioning on the basis of 24 h operation. The change in weight in all of the timbers was followed in the drying chamber and drying stopped when the desired weight was achieved. At 40 oC dry bulb temperature, 0.8 m/s air velocity, and initial moisture content of the poplar timbers 1.28 kg water/kg dry matter, the moisture content was reduced to 0.15 kg water/kg dry matter moisture content in 70 h, and the moisture content of the pine timbers which was 0.60 kg water/kg dry matter was reduced to the same amount in 50 h. While drying process, drying air temperature and relative humidity and weight change of timbers were collected on the computer and observed computer screen. Energy and exergy and drying time analyzed by using saved computer data afterwards drying process. As a result of analysis, coefficient performance (COP) of heating was calculated as 1.86 for whole heat pump dryer. Specific moisture extraction ratio (SMER) was calculated as 0.188 kg/ kWh for pine timbers and 0.243 kg/kWh for poplar timbers. The psychometric analyses was made of climatic variation of drying air in heat pump dryer and comparison was made between experimental data and calculated theoretical data. Key Words : Drying, timber, heat pump