How does a boiler blowdown vessel work?
Boiler blowdown is water intentionally wasted from a boiler to avoid concentration of impurities during continuing evaporation of steam. The water is blown out of the boiler with some force by steam pressure within the boiler.
What is the minimum size piping for bottom blowdown lines?
7.5 m
In practice, a reasonable minimum length of blowdown line is 7.5 m, and most blowdown vessels are sized on this basis.
What is blowdown ratio?
Rate of blowdown is a rate normally expressed as a percentage of the water feed. In the case of boilers, rate of blowdown is the removal rate of water from a boiler. Its purpose is to control boiler water parameters within prescribed limits to minimize: Scale. Corrosion.
What is a boiler blowdown vessel?
Blowdown vessels are designed to reduce the pressure of the blowdown discharge from the boiler to atmospheric pressure, and also reduces the blowdown discharge to drain to acceptable temperatures for compliance to water bylaws.
How many level indicators are there in the water level indicator of a boiler?
Two water level indicators
How many level indicators are there in the water level indicator of a boiler? Explanation: The function of the water level indicator is to indicate the level of water inside the boiler drum at any given instant. Two water level indicators (one as a standby) are fitted at the front of the boiler drum.
How do you calculate boiler cycles?
A boiler cycle is the number of times TDS present in feedwater can concentrate. For example, 100 TDS feedwater, cycled five times, would result in 500 TDS. Example: If boiler conductivity = 1,000 and feedwater conductivity = 100, the boiler is achieving 10 cycles.
How do you measure a boiler blowdown?
The optimum blowdown rate is determined by various factors including the boiler type, operating pressure, water treatment, and quality of makeup water. Blowdown rates typically range from 4% to 8% of boiler feedwater flow rate, but can be as high as 10% when makeup water has a high solids content.
What is intermittent blowdown?
Intermittent blowdown involves hot, high pressure water, flowing for short periods of time. When this water is reduced to atmospheric pressure it will partially vaporize.
How is boiler efficiency calculated?
In order to calculate boiler efficiency by this method, we divide the total energy output of a boiler by total energy input given to the boiler, multiplied by hundred. GCV= Gross calorific value of the fuel.
What is the function of blowdown valve of a boiler?
The primary purpose of blowdown is to maintain the solids content of boiler water within certain limits. This may be required for specific reasons, such as contamination of the boiler water. In this case, a high blowdown rate is required to eliminate the contaminants as rapidly as possible.