Can a scraper film evaporator be used with an MVR system?
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I want to build a small falling film evaporator, replacing the tube heat exchanger with a centrifugal scraper. Could anyone tell me if a scraper film evaporator can be used in combination with an MVR system? Because it seems to allow combining the advantages of both, especially as it is less prone to scaling when evaporating wastewater. If possible, what is the optimal temperature for evaporation control?
Of course, MVR refers to a compressor that is used for the secondary compression of steam. A small amount of steam is not cost-effective.
For evaporators with a low water volume, customers are willing to accept slightly higher energy consumption. After all, the cost of electricity is much lower than the cost of outsourcing the task.
Firstly, scraper evaporators are suitable for evaporating materials with high viscosity; due to their limited heating area, the amount of material that can be evaporated is not large. The MVR system is not economical when the steam volume is low. Another point is that wastewater evaporation usually involves large-scale shell-and-tube heat exchangers combined with MVR.
Thank you for your reply. I believe that, given the current environmental conditions, the price for outsourcing the treatment of wastewater concentrate is 4,500 yuan per ton. Therefore, controlling the amount of the concentrated solution is of utmost importance. Doubling the concentration reduces the processing cost by half. Even if it costs more in electricity bills, it’s still worth it. Furthermore, the scraper has a higher heat exchange efficiency, so less area is required to achieve the same output. Moreover, for environmental protection purposes, machines with a capacity of dozens of kilograms per hour, or one to two hundred kilograms per hour, are used; therefore, I think the feasibility is quite high.
I had this idea quite early on and consulted our process engineers; they said it wasn’t possible. But what you’re describing seems like something that can’t be vaporized – we could try conducting an experiment to see
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