A design for a special flash tank.

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There is water with a salt content of 25% in the project, and it contains trace amounts of toluene; the manager wants to remove the toluene from it through flashing. My design is like this. With a feed of 2 kilograms at around 125°C, it is feasible to use the proII simulation definition of a flash tank for pressure-normalized simulations. The special feature is that 1. normal flashing involves throttling in the pipes (is throttling necessary? (It’s been confusing me), while in my case I set the flash tank at atmospheric pressure, with the gas entering the heat exchanger to condense. 2. Normal flashing is single-component gas-liquid separation. As for me, it involves multiple components; it can actually be considered as one theoretical plate. The reason it wasn’t designed as a distillation process is mainly that distilling solutions with high salt concentrations is quite difficult. Additionally, I don’t have very high requirements regarding the flow rate and composition of the gas phase. I would like to ask my senior colleagues: 1) Is this separation method feasible for me? Are there any similar cases among peers? Operating procedures for starting and stopping. 2) For the design of the flash tank, I referred to HG/T20570 on the design of gas-liquid separators; in general, the gas flow velocity must be lower than the floating velocity of the suspended droplets. The dimensions of the pipe connections inside are not specified clearly. The fluid flow velocity at the liquid outlet connection should be less than or equal to 1 m/s, and the diameter of the gas outlet connection must be at least as large as the diameter of the pipe it is connected to? (1) Why is there a requirement that the flow velocity at the liquid outlet connection be less than 1 m/s? I just need to ensure the liquid level in the flash tank is maintained; the flow rate actually doesn’t matter. (2) How exactly should the diameter of the gas outlet pipe be calculated, and what value should be used for the gas flow velocity? I saw some people on the forum say 2 m/s, which seems a bit inappropriate; normal gas flow speeds are around 10 m/s, which is an order of magnitude higher. This directly affects the size of the subsequent device takeover. 3) Are there any special requirements regarding the internal design of a flash tank like mine, such as foam removal? Moreover, it is used for high-salinity flashing; are such components usually designed by the manufacturer or specified based on calculations done by engineering firms?