What is a common continuous blowdown rate on many boilers, expressed as a percentage of steaming rate?

The continuous blowdown rate of a boiler is crucial for maintaining water quality and overall boiler efficiency. A common blowdown rate is around 1% of the steaming rate. This rate balances the need to remove impurities from the boiler water while minimizing heat and water loss.

When water is heated in a boiler, it can accumulate dissolved solids over time. If left unchecked, these solids can concentrate and lead to scaling and corrosion, which negatively affect performance and longevity. To manage this, a small percentage of water is continuously removed from the system—this is known as blowdown.

By setting the blowdown rate at about 1%, operators can effectively control water chemistry without incurring excessive losses in water and energy. A higher blowdown rate may be necessary in certain situations with poor water quality or high rates of dissolved solids, but for most scenarios, 1% is a practical standard that helps maintain efficient operation while safeguarding boiler integrity.