Multiple-effect horizontal pipe falling film evaporation sea water desalting plant with middle vapor-liquid separation

Abstract

The invention relates to a multiple-effect horizontal pipe falling film evaporation sea water desalting plant with middle vapor-liquid separation, belonging to the technical field of sea water desalting and heat-exchange equipment. The multiple-effect horizontal pipe falling film evaporation sea water desalting plant with middle vapor-liquid separation is characterized in that a middle vapor-liquid separation pipe box is arranged in each first-effect evaporator / condenser, and a heat exchange pipe bundle is divided into a front pipe bundle section and a rear pipe bundle section by the middle vapor-liquid separation pipe box; in each first-effect evaporator / condenser, the vapor channel is divided into three pipe passes: a first pipe pass in the front pipe bundle section, a second pipe pass in the heat exchange pipes on the lower part of the rear pipe bundle section, and a third pipe pass in the heat exchange pipes on the upper part of the rear pipe bundle section; the number of heat exchange pipes in each side pass is smaller than that in the previous pipe pass; the vapor flow directions in the first pipe pass and the second pipe pass are identical, and the vapor flow direction in the third pipe pass is opposite those in the first pipe pass and the second pipe pass. The invention overcomes the defect that the effective heat transfer area is reduced since condensate is aggregatedat the middle rear part of the traditional long horizontal pipe and the defect that the coefficient of heat transfer is reduced due to over-low vapor flow velocity, enhances the condensing coefficient of heat transfer in the rear part of the pipe and reduces the heat transfer pipe consumption.

Description

technical field [0001] The invention belongs to the technical field of seawater desalination and heat exchange equipment. It relates to a multi-effect horizontal tube falling film evaporation seawater desalination device, in particular to a multi-effect horizontal tube falling film evaporation seawater desalination device with intermediate vapor-liquid separation. Background technique [0002] At present, the current large-scale multi-effect evaporation seawater desalination device in the world is a device that uses steam as the main energy source for seawater desalination. Its main body is composed of a series of evaporators / condensers. The long horizontal tube bundle is composed of falling film evaporation of seawater outside the horizontal tube and condensation of steam inside the tube. The structural diagram of the first-effect evaporator / condenser is shown in figure 1 . [0003] The multi-effect evaporator horizontal tube falling film evaporation seawater desalination...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a multi-effect horizontal tube falling film evaporation seawater desalination device with intermediate vapor-liquid separation, which can increase the effective heat exchange area between the steam in the horizontal heat exchange tube and the tube wall, and maintain a relatively high temperature in the tube. The steam flow rate solves the problem of poor heat transfer effect at the rear of the conventional horizontal tube falling film evaporation / condenser long tube

Images