Boiler Blowdown Energy Recovery

摘要

Boiler blowdown is essential for the continued operation of any boiler. Without blowdown, chemical concentrations within the boiler water can increase above acceptable limits, potentially leading to boiler damage. Typical problems associated with insufficient blowdown are tube scale, corrosion, and liquid carryover. The liquid removed as boiler blowdown has received energy from the fuel supplied to the boiler. Therefore, the blowdown stream represents an energy loss in the boiler operations. There are two primary management activities that reduce the blowdown loss. First, boiler water treatment can reduce the amount of blowdown required to maintain proper boiler operations. Second, thermal energy can be recovered from the blowdown stream. A boiler operating with the best quality boiler feedwater will require some amount of blowdown to maintain water chemistry. Therefore, it is beneficial to investigate the benefits associated with recovering the thermal energy resident in the blowdown stream. Boiler blowdown energy management through the use of thermal energy recovery is the focus of this article.