The boiler drum is connected with downcomer and water wall to form a natural circulation loop. At the same time, the boiler drum receives the feed water from the economizer and delivers saturated steam to the superheater. Therefore, the boiler drum is the connecting hub of the three processes of heating, evaporation and overheating in the boiler.
Water treatment outside the boiler
Before entering the boiler, raw water is treated with water treatment equipment to remove impurities such as hardness, salinity, dissolved oxygen, etc., so that the feed water can meet the water quality requirements specified by steam boiler. Common water treatment equipment includes sodium ion exchange water softening equipment, ion exchange desalination equipment, reverse osmosis water purification equipment and thermal oxygen removal equipment.
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A cornertube boiler is a type of natural circulation water-tube boiler which differentiates itself from other water tube boilers by its characteristic water-steam cycle and a pre-separation of heated steam from the steam-water mixture occurs outside the drum and the unheated downcomers.
The steam boiler in the packaging plant is mainly used in the heating process before the raw paper is made into cardboard. In brief, it is using steam which contains no water in the drying process to improve the production efficiency and product quality of packaging cartons. As a result, it has high requirements for the steam and steam boiler, such as temperature, water content, rated evaporation capacity per unit time, etc., which are important parameters in the boiler selection.
There are many opinions on the best way to clean a steam boiler. One of the oldest ways is to dissolve a pound of tri-sodium phosphate (TSP) and a pound of caustic soda (lye) in water and pour it into the boiler. Let it cook for a few hours and then drain the boiler. If you can't buy TSP in your town, try a commercial soap called MEX. It works well and will not damage the rubber gaskets found in some boilers. However, before you clean any boiler, check the manufacturer's instructions for their recommendations.
The coal-fired steam boiler is a forced circulation high-pressure single-tube DC boiler. Its operation process includes three processes: the combustion process of the fuel, the heat transfer process of flue gas to water and the vaporization process after water absorbs heat. In order to better control these different processes, the control system should make
the heat of pulverized coal combustion adapt to the requirements of steam load changes and dryness.
If the final temperature of feed water doesn’t reach the saturated temperature after being heated by an economizer, (that is, the feed water has not reached the boiling state), we call the economizer as a nonsteaming economizer. Generally, the final temperature is 30-50℃ lower than the saturated temperature.
Loads vary, and a power plant must be capable of handling the minimum load, the maximum load, and any load variations. Boiler selection is often dictated by the variation in load demand, rather than by the total quantity of steam or hot water required. There are three basic types of load variations: seasonal, daily, and instantaneous.