Boiler drum and regenerator
Thread Content
In our waste heat recovery system, there are three regenerators, and each regenerator is equipped with a pneumatic valve. Then it is connected to the steam drum. The question is, what determines the opening degree of these three pneumatic valves? ? For what reason? ?
When the drum pressure rises, the pneumatic valve opens to accept the excess steam, and then closes. When the air tank pressure drops to a certain level, the pneumatic valve opens to release steam.
:(See this explanation: To prevent the liquid level inside all the steam drums connected to the high-pressure collector from rising rapidly, due to high steam flow rates that could trigger the boiler protection system via the LZH alarm and cause shutdown, the steam flow rate from the steam drums must be limited to its maximum allowable value during the heating phase of the steam accumulator, until the accumulator is connected to the steam network under normal operating conditions. Do you understand what this means?)
:(See this explanation: To prevent the liquid level inside all the steam drums connected to the high-pressure collector from rising rapidly, due to high steam flow rates that could trigger the boiler protection system via the LZH alarm and cause shutdown, the steam flow rate from the steam drums must be limited to its maximum allowable value during the heating phase of the steam accumulator, until the accumulator is connected to the steam network under normal operating conditions. Do you understand what this means?)
It is possible that the pressure generated by the boiler is much higher than the pressure required by the process steam; therefore, when the demand for process steam is low, the boiler pressure can be increased to fill the regenerator. When the pressure in the regenerator is sufficient but the output of the waste heat boiler is insufficient, the outlet pressure can be adjusted to meet the process requirements. That’s probably what you mean by what you said. . Pressurizing the empty regenerator when there is a high steam flow rate in the drum causes a sudden drop in drum pressure, resulting in a false flash level and a rapid increase in the liquid level. Therefore, when filling the drum with steam, the steam flow rate also needs to be adjusted; one reason is to preheat the heat accumulator, and the other is to prevent sharp changes in the drum’s water level.