Even with the best pretreatment programs, boiler feedwater will contain some degree of impurities, such as suspended and dissolved solids. These impurities can accumulate inside the boiler over time. The increasing concentration of dissolved solids may lead to carryover of boiler water into the steam, causing damage to piping, steam traps, and even process equipment. The increasing concentration of suspended solids can form sludge, which impairs boiler efficiency and heat-transfer capability.
To avoid boiler problems, water must be periodically discharged or “blown down” from the boiler to control the concentrations of suspended and total dissolved solids in the boiler.
Sterling’s Blowdown Tank receives blowdown from the steam drum and steam generator. Sterling’s Blowdown Tank can also function as a gravity feed drain for the steam generator when the generator is drained for maintenance.
In Sterling’s design, flashing water enters the tank tangentially where centrifugal action separates the liquid from vapor. Flashed steam exits through a nozzle in the top of the tank, while the liquid is drawn from the bottom of the vessel.