摘要 |
Steam is generated using high total dissolved solids (TDS) boiler feedwater while still maintaining relatively low boiler blowdown rates. In one embodiment, a boiler is adapted to generate low quality steam from the high TDS feedwater to maintain wet conditions in the boiler tubes to mitigate against fouling/scaling problems. The low quality steam is then separated into a vapor fraction and a liquid blowdown stream. The vapor fraction is superheated to superheated steam. The liquid blowdown stream is allowed to exchange heat with the thus-created superheated steam to vaporize a portion of the blowdown to form a finished steam and a waste stream. This reduces the blowdown to waste and creates more end user steam. The finished steam is routed to its end use, e.g., a hydrocarbon thermal recovery process. Advantages include lower cost, higher efficiency, and less equipment complexity. |