Low-pressure drop ethylbenzene evaporator and energy-saving process for ethylbenzene vaporization in styrene dehydrogenation reaction system

Abstract

Disclosed herein is a low-pressure drop ethylbenzene evaporator, comprising a double-layer structure consisting of a heat exchange unit and a gas-liquid separation unit, the upper layer and the lower layer thereof being connected via an intermediate pipe. The top of the gas-liquid separation unit is provided with an exhaust pipe, and the bottom is provided with a separated liquid return pipe. The heat exchange unit comprises a housing side and a heat exchange pipe, the bottom of the housing side being provided with a liquid flow inlet, and a low-pressure vapor feed pipe being disposed on a side wall of the housing side, located below the heat exchange pipe and close to the position of the heat exchange pipe. In an energy saving process for ethylbenzene vaporization of the present application, a large amount of heat is recovered by means of a main cooler to generate a vapor at 6-32 kpaA, which is used for primary vapor distribution of the ethylbenzene vaporizer design of the present application after being pressurized by a compressor, and is used to replace supplemental 0.21 MPaG low-pressure vapor for a vapor pipe network of a related device, greatly reducing consumption of low-pressure steam in the reaction system, as well as decreasing the amount of circulating water used in the device. The process only consumes the power consumption of a compressor, and saves a large amount of low-pressure vapor and circulating water.