Table of Contents
Why does my boiler blow down?
Boiler blow down is done to remove carbon deposits and other impurities from the boiler. Blow down of the boiler is done to remove two types of impurities – scum and bottom deposits. To remove the precipitates formed as a result of chemical addition to the boiler water.
What is bottom blowdown?
Bottom blowdown, the removal of boiler water and sludge from the lower portions of a boiler, is a common practice used to prevent deposition on heat transfer surfaces.
How do you blow the bottom of a boiler?
The following steps should be taken to blow down a boiler.
- Open the quick-opening valves (ones closest to the boiler).
- Open the slow-opening valve.
- Blow down the boiler for the amount of time specified by your water management consultant by opening and then closing the slow-opening valve.
- Close the slow-opening valve.
What is bottom blow down and why it is done?
Bottom blowdown is the removal of the sludge which accumulates in the bottom of a firetube boiler, or in the mud drum of a watertube boiler. The sludge is removed regularly to prevent buildup which could foul the heat transfer surfaces and lead to vessel or tube failure.
How often blow down steam boiler?
once every 8 hour shift
How often should a boiler have a bottom blowdown? The most common recommendation for the frequency of bottom blowdown of a steam boiler is at least once every 8 hour shift.
How do you treat a blowdown on a boiler?
Boiler blowdown is a difficult stream to treat. A combination of technologies is required to get a stable operation. One of the most efficient used techniques is reverse osmosis. Reverse Osmosis membranes are used to separate dissolved ions and produce a high quality permeate.
What action should be taken before carrying out a bottom blowdown on a steam boiler?
Open the valves:The bottom drain line on your boiler usually has two valves — a slow-opening gate valve and a quick-opening knife valve. The proper way to bottom blow down a boiler is to start with both valves fully closed. Next, open the knife valve first before completely opening the gate valve.
How does a boiler blowdown separator work?
A boiler blowdown separator is designed to take water from the boiler during blowdown and reduce it to atmospheric pressure for disposal. As the blowdown enters the vessel, it is forced into a centrifugal pattern by means of a striking plate. The steam is vented to the atmosphere through a top connection.
What are the factors affecting the frequency of a boiler blow down?
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 blow down process?
Blowdown is the removal of water from a boiler with the help of a blowdown valve. This valve removes the dissolved solids in the boiler water through the boiler exit port. Blowdown is also associated with heat exchangers or cooling towers in the industrial processes which use water.
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.