Regarding the calculation of the steam output from waste boilers?
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Have you still not been able to find any relevant information or references for calculating the steam generated as a by-product of waste boilers? If the water inflow rate into the waste boiler remains constant, the amount of steam generated should be equal to that water inflow rate in order to maintain material balance! However, the author has observed that in practice this is not the case; the amount of steam is often less than the amount of water Is it difficult to achieve balanced cascade control for waste boilers? Why? Is it a problem with the design of the boiler? Is it simply impossible for this junk of a stove to achieve good results?
I also want to know the answers to the questions posted by the original poster; I’m following it. . . . . . . .
Is it related to design? It’s the same here as well.
People at 3# Yaozhiqing Design Institute are aware of it, but they keep this calculation confidential!
Boilers have blowdown systems, either intermittent or continuous, so generally the amount of steam produced is less than the amount of water fed in.
The issue you mentioned is quite simple. The principle involves considering the water supply, steam, and the heat released by the waste heat exchanger as one system; the heat absorbed by the boiler water equals the heat released by the waste heat exchanger. When there is slag discharge, the amount of steam produced plus the amount of slag discharged equals the amount of water supplied. If there is no slag discharge, then the amount of steam produced equals the amount of water supplied. In actual operation, the amounts of steam produced and water supplied do not always match for two reasons: first, flow measurement – while orifice plates are accurate for measuring liquids, they tend to give lower readings for gases, which is exactly the situation you described. Second, the separation efficiency of the drum is poor, resulting in steam containing water, and thus the measured value of steam is much lower than that of the water supply. I have encountered this second issue before, and it was only resolved after modifying the internal components of the drum.
6# A Pine Tree: How long does it take for your air strips to become wet? Did it happen frequently before the technical upgrade? If it happens frequently, can your steam coil handle it?
Can it be understood this way: by maintaining a stable water level in the boiler, if no water is drained, then the heat calculation simply involves the balance between the water entering the boiler and the steam produced? The water in the boiler can be ignored! What considerations does the design institute take into account when conducting design calculations?
What the original poster mentioned – that the steam generated by the waste boiler is less than the amount of water flowing in – is also a normal phenomenon, as the waste boiler has a system for discharging wastewater
As for the design reason for the waste boiler, in our factory, the ratio of water to steam fed into the waste boiler is 1:0.75
There seems to be nothing to keep secret about this design – it’s just the law of conservation of energy! It should be noted that when designing fire-tube waste heat boilers, a sewage loss of 3% due to water inlet and a heat loss of 5% due to heat exchange with the environment must be taken into account.