| Title | Unit 1 Cooling Tower Fan Stack Replacement to Improve Cooling Tower Perfomance |
|---|---|
| Authors | Amri ZEIN, Djamaludin KURNIADI |
| Year | 2015 |
| Conference | World Geothermal Congress |
| Keywords | Wayang Windu, fan stack, air flow, wet bulb, recirculation, velocity recovery, cooling tower performance. |
| Abstract | Unit 1 Cooling Tower (CT) fan stack was designed with height of 6 feet and had relatively straight vertical panels which didn’t produce significant velocity recovery. In other hand, due to Wayang Windu Geothermal Plant is located in the mountain; the CT is exposed to swirling and shifting winds. These types of winds can force down the exiting plume (hot air) from the CT and drawn back into the CT which increases the entering wet bulb temperature. This phenomenon is called recirculation. The increasing of wet bulb temperature will impact to decreasing of CT performance. Star Energy Geothermal Wayang Windu Ltd. conducted an engineering study and recommended that CT performance can be improved by replacing the existing fan stack with higher fan stack (10 feet tall) which has a flared velocity recovery design. This new design fan stack will convert some of the wasted velocity pressure energy at the top of fan stack into useful work at the plane of the fan; therefore fan efficiency will be increased. By improving fan efficiency, additional motor power can be made available to further increase the air drawn through CT; thus, overall CT performance can be improved. In addition, this new design also reduces the effect of recirculation. The fan stack replacement work was completed in Dec 2011. CT performance test reveals data of decreasing of approach temperature as much as 1.44oC, an increasing of range temperature as much as 1.92oC, and increasing of CT effectiveness as much as 71.43% (from 66.26%). The impact is equivalent with generation improvement of 1.44 MW. |