Gas water

The term \"primary tar separator\" is not a standard term after vacuum flash evaporation; in coal tar processing, it actually refers to the \"tar-ammonia water separator\" or the gas-liquid separation device located after the initial distillation tower/evaporator. Its main function is to rapidly separate the tar phase, light fractions (such as water, ammonia, and light oils), and non-condensable gases following vacuum flash evaporation (which reduces the boiling point and prevents thermal decomposition). Structurally, they are mostly vertical or horizontal gravity settling tanks, equipped with baffles and foam breakers (demisters); some also have heating jackets or mixing devices ； The inlet is usually located in the middle or upper part, the outlet (gas phase) is at the top, while the tar liquid phase is discharged from the bottom; free water/light oil can be separated via side lines or stratified overflow. Working principle: The mixture resulting from vacuum flashing (containing tar, water vapor, light oil vapor, ammonia, and non-condensable gases) enters the separator, where a sudden drop in pressure and temperature causes some high-boiling-point components (such as phenol oil and naphthalene oil) to condense. In the area with low flow velocity, the gas and liquid phases separate due to gravity ； The liquid droplets entrained in the vapor are captured and returned through baffle deflection or wire mesh mist eliminators ； The density difference causes the tar (the heaviest) to settle at the bottom, while the aqueous phase (intermediate in density) or the light oil phase (lightest) forms separate layers, which are then discharged at regular intervals or continuously through different outlets ； Non-condensable gases (such as H₂S, NH₃, CH₄) are recovered by condensation at the top and then vented or fed into the gas system.