Results vacuum distillation unit

The connection between pump and distillation unit also requires consideration. As large gas volumes are present under vacuum, pipe connections have to be short and wide. If the pipe diameter is too small, a pressure loss results and the pump s suction efficiency decreases. The pressure loss due to the flow conductance is the reciprocal sum of all connecting parts from the pump to the distillation unit. With short pipes at least the diameter of the pump s intake port has to be selected longer pipes require correspondingly larger pipe diameters. Pump manufacturers (see 2.1.3.5) usually provide the necessary information. 

Regardless, I tried culling ihe steam back to 5,000 Ib/hr to see how much the vacuum distillate rate would increase. Surprisingly, the flow of vacuum distillate remained constant. The only notable result on the crude unit was a drop in flow of wet gas from the reflux drum. The 3,000 Ib/hr cut in the bottom s stripping steam had unloaded the overhead condenser. This caused the reflux drum temperature to drop and hence reduced the flow of wet gas to the off-gas compressor. 

The devolatilizer (7) is held under a very high vacuum to remove unreacted monomer and solvent from the polymer melt. The monomer is distilled in the styrene recovery unit (8) and recycled back to the prepolymizer. The polymer melt is then pumped through a die head (9) to form strands, a waterbath (10) to cool the strands, a pelletizer (11) to form pellets and is screened to remove large pellets and fines. The resultant product is air-conveyed to bulk storage and packaging facilities. 

The processing of Russian crude in the above mentioned unit results in a vacuum residue with boiling point of over 585°C. Progressive distillation yields the following fractions ... 

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