METHOD FOR TREATING HIGHLY CONCENTRATED WASTEWATER BY REDUCED PRESSURE EVAPORATION AND APPARATUS THEREFOR

摘要

PURPOSE: Provided are a method for treating highly concentrated wastewater by reduced pressure evaporation and a device therefor, which maximizes a heat transfer efficiency of a heat exchange pipe, removes floating matters from a vibration screen under optimal conditions and preheats wastewater in a wastewater preheating and supplying device to periodically supply the preheated wastewater to an evaporation pipe. CONSTITUTION: The method comprises steps of after flowing a washing port and wastewater in an inlet part(2) of a flowing hole separator(1) for washing an outside circulatory type heat exchange pipe, moving the washing port to a washing port inlet part(8) and spraying the wastewater with high speed from a high temperature wastewater sprayer(14) to a vaporizing pipe(41); after increasing the temperature of high temperature vapor vaporized from the vaporization pipe in a vapor compression pump(46), making the temperature-increased vapor let in a vaporized warm water inlet part(60) of the heat exchange pipe to increase the temperature of a wastewater and a washing port passing pipe at a vaporized warm water passing pipe(17) and passing it through a vaporized warm water outlet part(61); mixing the wastewater in the vaporizing pipe with the washing port at a washing port inlet part(8) and moving the mixture to an inlet part(12) of the heat exchange pipe; colliding the washing port with pipe walls by an eddy formed at a cyclone device(13) and an induction pipe(15) to continuously remove scales adhered to walls of the passing pipe and discharging the scales through a wastewater washing port outlet(19); continuously circulating the wastewater in a reduced pressure vaporization pipe(41) through a heat exchange pipe(11), the flowing hole separator and the reduced pressure evaporation pipe to increase the temperature of wastewater resulting in repetitive reduced pressure evaporation and making the evaporated vapor get in the vaporized warm water inlet part; supplying flow adequate for optimum conditions of a vibrating screen from a highly concentrated wastewater raw water tank to a raw water pump by installing a flow rate control part and returning the remnant flow to the raw water tank; after continuously circulating concentrated water by a concentrated water circulation pump, discharging the concentrated water to a concentrated water storage tank(46) by opening a concentrated water valve and then caking or composting it; after removing fine floating particles contained in the vaporized vapor in a demister and compressing the vapor in a vapor condensing pump to increase the temperature thereof, putting it in a vaporized warm water inlet part(60) and then spraying it in front of a cooling fan to cool down; and circulating a portion of the cooled water as a cooling water of the pump and a rotator and outflowing or recycling the remnant.