Is there any value in recycling the regular and continuous blowdown from small-tonnage saturated steam boilers?
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We have a hospital project that involves a total of 4 steam boilers with a capacity of 4 t/h each. The continuous and periodic drainage is discharged into the atmosphere after going through corresponding expansion processes. I would like to know whether it is possible to recover the heat generated in this process How to enable recycling?
To determine whether there is value in recycling, a technical and economic analysis is required.
It has recycling value; a water tank with internal coils can be built, allowing the drainage water to flow through the coils and heat the tap water in the tank, thereby providing hot water for bathing. Our company has a 20-ton furnace that recycles 20 tons of wastewater per day, sufficient to provide hot water for bathing for 100 people per day.
No, the amount of steam collected is so small that it’s not even enough to provide insulation; moreover, additional equipment has to be invested, which isn’t worth it.
Most of the waste water generally flows directly into ditches, but I have seen papers on this topic in the past.
If the boiler is medium-pressure, the continuous exhaust can produce low-pressure steam at 7 kilograms of pressure. If the boiler is low-pressure, the exhaust steam pressure is even lower. In short, the quality of the steam produced in series is low, making it of little use.
I think there is value in recycling it, as the temperature of the wastewater is relatively high and its thermal value is high, making recycling profitable.
Is there any value in recycling it? It depends on how you look at it. I once visited a facility at Magang for the utilization of waste heat from sintering; there, the Japanese-owned equipment used condensed water to heat the feedwater – even just 1 degree of heating – and they didn’t spare such a small amount of heat either. Therefore, I believe that the waste steam generated should still be recovered and used to heat the feedwater.
This issue needs to be considered on a case-by-case basis. If all 1.4 boilers operate continuously. It should be considered, because releasing substances into the atmosphere is truly a waste. Secondly, it also looks unsightly from an energy-saving perspective. If one or two units operate intermittently, it seems there’s no need to make a big deal out of it. Because an investment is needed for the previous project, and the results may not necessarily be obvious. The energy available for wastewater treatment is limited, and the levels of Ca and Mg in the water exceed the permissible limits. There is also a maintenance issue with operating for long periods of time.
This project was implemented; the management didn’t use it, and emissions occurred. . .