CN102745852B

CN102745852B - Brine-desalination method

Info

Publication number: CN102745852B
Application number: CN201210248085.6A
Authority: CN
Inventors: 文彬; 杨丹红; 任英杰
Original assignee: Xinjiang Technical Institute of Physics and Chemistry of CAS
Current assignee: Xinjiang Technical Institute of Physics and Chemistry of CAS
Priority date: 2012-07-18
Filing date: 2012-07-18
Publication date: 2014-05-07
Anticipated expiration: 2032-07-18
Also published as: CN102745852A

Abstract

The invention aims to provide a brine-desalination method, which organically combines a distillation method and a membrane method for brine desalination, the high pressure of the strong brine of the membrane method is utilized to drive the negative pressure of a Venturi injection pump for lowering the subsequent evaporating pressure, so the evaporating process is carried out under the atmospheric pressure, the evaporating temperature can be effectively reduced, the evaporating energy consumption is saved, the concentration of the evaporating raffinate is high, and moreover, the heat of the evaporating raffinate is utilized for the subsequent crystallization; and the latent heat of the evaporated steam is effectively utilized to heat the brine to be evaporated, the heat energy is further recovered, and the energy consumption is lowered.

Description

A kind of method of water desalination

Technical field

The present invention relates to a kind of brackish water desalting method.

Background technology

Pollution to used water resource in a large amount of exploitations of the water resources that increases, can directly utilize for the mankind along with world population and process of industrialization, tellurian Freshwater resources day by day reduce and worsen, drinkable water distribution of resource is also very uneven, in order to tackle the situation of Freshwater resources scarcity, various places all attempt utilizing local used water resource to adopt various treatment technologies to produce fresh water, and applying maximum is the processing of sea water desaltination, brackish water desalination and high density salt solution.

At present, saline-water reclamation method mainly contains distillation method, cold method, ion exchange method and embrane method, the development of desalination techniques is mainly object round reducing energy consumption and cost, distillation method has multiple-effect evaporation, multistage flash evaporation etc., cold method is because energy consumption is large, mainly utilize the natural cooling source in winter to realize, ion exchange method has electro-adsorption, electrodialysis etc., and embrane method mainly contains nanofiltration membrane, ultra-filtration membrane, reverse osmosis membrane, electrodialysis (ion-exchange membrane).Distillation method principle is simple, but energy consumption is large, uses low-temperature evaporation can effectively reduce energy consumption, and along with the development of film production technology, the cost of embrane method desalination salt solution has become the most competitive saline-water reclamation process.

The present invention organically combines distillation method and embrane method, utilize the negative pressure that the high drive Venturi squirt pump of the strong brine side of embrane method produces to reduce follow-up evaporating pressure, make evaporative process lower than carrying out under normal atmosphere, can effectively reduce vaporization temperature, increase additional issue amount, save evaporation energy consumption, the concentration that makes to evaporate raffinate is higher, utilizes the heat of evaporation residue dope to carry out the crystallisation process of postorder simultaneously; Effectively utilize the latent heat of evaporated vapor to heat salt solution to be evaporated, further reclaimed heat energy, reduced energy consumption.

Summary of the invention

The object of the invention is to provide a kind of method of water desalination, the method organically combines the distillation method for brine desalination and embrane method, utilize the negative pressure of high drive Venturi squirt pump of the strong brine side of embrane method to reduce follow-up evaporating pressure, make evaporative process lower than carrying out under normal atmosphere, can effectively reduce vaporization temperature, save evaporation energy consumption, the concentration that makes to evaporate raffinate is higher, utilizes the heat of evaporation residue dope to carry out the crystallisation process of postorder simultaneously; Effectively utilize the latent heat of evaporated vapor to heat salt solution to be evaporated, further reclaimed heat energy, reduced energy consumption.

A kind of water desalination method of the present invention, follows these steps to carry out:

Tank (3) in the middle of a, Jiang Yuanshui (1) enter after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, cartridge filter pre-treatment (2), then through topping-up pump 4, enters membrane treatment appts (5) and carries out membrane filtration, obtains film and processes water purification (14);

B, the water purification (14) after film is processed come into operation, remain dense water and go out moisture two-way, one tunnel enters Venturi squirt pump and penetrates at a high speed, tank (3) circular treatment in the middle of entering, separately lead up to non-return valve (7), after interchanger (15) and well heater (8) heat temperature raising, through throttling valve (9), enter cryogenic vaporizer (10), steam is condensed after interchanger (15) transfers heat to strong brine, enters distillation water pot (11);

C, cryogenic vaporizer (10) bottom strong brine out enter crystallization apparatus (12) and isolate salt (17) and water, and a part of water vapor recovery evaporating enters distillation water pot (11) and can obtain distilled water (16).

Described step a Central Plains water (1) is brackish water or salt solution or seawater.

Membrane treatment appts in described step a (5) is nanofiltration membrane or reverse osmosis membrane processing device, and the use of these two kinds of films all needs larger pressure to promote.

In described step b, Venturi squirt pump is that high pressure fluid produces at a high speed the device of negative pressure when the undergauge pipe section in chamber, rear flank.

The method of a kind of water desalination of the present invention, the feature of the method is: the pressure energy that utilizes the strong brine side of membrane treatment appts, drive Venturi water jet pump to produce negative pressure, the evaporative process of strong brine is carried out under negative pressure, reduced the vaporization temperature of water, reduce the energy consumption that adds hot salt brine, utilized the latent heat of vaporization that water vapor condensation is emitted to heat strong brine to be evaporated simultaneously, effectively reduced the cost of salt solution concentrating and separating.Different according to raw water quality in former water pretreatment, preprocessing process can adjust accordingly, and object is to meet the water quality requirement that enters membrane treatment appts.

Accompanying drawing explanation

Fig. 1 is process flow sheet of the present invention.

Embodiment

Embodiment 1

A, salt solution 1 is entered after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, cartridge filter pre-treatment 2 in the middle of tank 3, then through topping-up pump 4, enter reverse osmosis membrane processing device 5 and carry out membrane filtration, obtain film and process water purification 14;

B, water purification 14 after film is processed can store or come into operation, residue strong brine goes out moisture two-way, one tunnel enters Venturi squirt pump and penetrates at a high speed, tank 3 circular treatment in the middle of entering, the non-return valve 7(of separately leading up to prevents that pipeline inner fluid from flowing backwards), after interchanger 15 and well heater 8 heat temperature raisings, (evaporation that heating unit 8 is water vapor provides heat energy, can adopt various forms of process furnace, power plant with good conditionsi can be used waste hot steam as thermal source, the place of illumination abundance can be used sun power that thermal source is provided, as solar water heater), the effect of salt solution decompression in throttling valve 9(plays to pipeline, so that after salt solution decompression, obtain larger steam output) enter cryogenic vaporizer 10, operation (negative pressure is from the back pressure of Venturi water jet pump 6) under negative pressure, salt solution can carry out carburation by evaporation in the boiling point situation lower than water, steam is condensed (interchanger 15 carrys out preheating salt solution to be evaporated for reclaiming the water vapor condensation liberated heat being evaporated) after interchanger 15 transfers heat to strong brine, enter distillation water pot 11,

C, cryogenic vaporizer 10 bottoms strong brine out enter crystallization apparatus 12 strong brine are separated into salt 17 and water, the a part of water vapor recovery evaporating enters distillation water pot 11 and can obtain distilled water 16, the effect one of pressure-balanced valve 13 is the smooth derivation that guarantee strong brine, the 2nd, and the velocity of evaporation of quickening crystallisation process.

Embodiment 2

The former water that the present embodiment is processed is brackish water, can be used for long area of sunshine duration.

A, brackish water 1 is entered after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, cartridge filter pre-treatment 2 in the middle of tank 3, then through topping-up pump 4, enter reverse osmosis membrane processing device 5 and carry out membrane filtration, obtain film and process water purification 14;

B, water purification 14 after film is processed stores or comes into operation, residue strong brine goes out moisture two-way, one tunnel enters Venturi squirt pump and penetrates at a high speed, tank 3 circular treatment in the middle of entering, the non-return valve 7(of separately leading up to prevents that pipeline inner fluid from flowing backwards), through interchanger 15, be solar water heater with well heater 8(herein) after heat temperature raising, the effect of salt solution decompression in throttling valve 9(plays to pipeline, so that after salt solution decompression, obtain larger steam output) enter cryogenic vaporizer 10, operation (negative pressure is from the back pressure of Venturi water jet pump 6) under negative pressure, salt solution can carry out carburation by evaporation in the boiling point situation lower than water, steam is condensed (interchanger 15 carrys out preheating salt solution to be evaporated for reclaiming the water vapor condensation liberated heat being evaporated) after interchanger 15 transfers heat to strong brine, enter distillation water pot 11,

Embodiment 3

The former water that the present embodiment is processed is seawater;

A, seawater (1) is entered after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, cartridge filter pre-treatment (2) in the middle of tank (3), then through topping-up pump 4, enter nanofiltration membrane treatment device (5) and carry out membrane filtration, obtain film and process water purification 14;

B, water purification 14 after film is processed comes into operation, residue strong brine goes out moisture two-way, one tunnel enters Venturi squirt pump and penetrates at a high speed, tank 3 circular treatment in the middle of entering, the non-return valve 7 of separately leading up to prevents that pipeline inner fluid from flowing backwards, after interchanger 15 and well heater 8 heat temperature raisings, (evaporation that heating unit 8 is water vapor provides heat energy, can adopt various forms of process furnace, power plant with good conditionsi can be used waste hot steam as thermal source, the place of illumination abundance can be used sun power that thermal source is provided, as solar water heater), the effect of salt solution decompression in throttling valve 9(plays to pipeline, so that after salt solution decompression, obtain larger steam output) enter cryogenic vaporizer 10, operation (negative pressure is from the back pressure of Venturi water jet pump 6) under negative pressure, salt solution can carry out carburation by evaporation in the boiling point situation lower than water, steam is condensed (interchanger 15 carrys out preheating salt solution to be evaporated for reclaiming the water vapor condensation liberated heat being evaporated) after interchanger 15 transfers heat to strong brine, enter distillation water pot 11,

C, cryogenic vaporizer 10 bottoms strong brine out enter crystallization apparatus 12 strong brine are separated into salt 17 and water, the a part of water vapor evaporating reclaims and enters distillation water pot 11, can obtain distilled water 16, the effect one of pressure-balanced valve 13 is the smooth derivation that guarantee strong brine, the 2nd, and the velocity of evaporation of quickening crystallisation process.

Claims

1. a water desalination method, is characterized in that following these steps to step and carries out:

Tank (3) in the middle of a, Jiang Yuanshui (1) enter after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, cartridge filter pre-treatment (2), then through topping-up pump (4), enter membrane treatment appts (5) and carry out membrane filtration, obtain film and process water purification (14), its Central Plains water (1) is brackish water or salt solution or seawater, membrane treatment appts (5) is nanofiltration membrane or reverse osmosis membrane processing, and the use of these two kinds of films all needs larger pressure to promote;

B, the water purification (14) after film is processed come into operation, residue strong brine goes out moisture two-way, one tunnel enters Venturi squirt pump and penetrates at a high speed, tank (3) circular treatment in the middle of entering, separately lead up to non-return valve (7), after interchanger (15) and well heater (8) heat temperature raising, through throttling valve (9), enter cryogenic vaporizer (10), the negative pressure of vaporizer (10) comes from the back pressure of Venturi squirt pump, steam is condensed after interchanger (15) transfers heat to strong brine, enters distillation water pot (11);

2. method according to claim 1, is characterized in that in described step b that Venturi squirt pump is that high pressure fluid produces the device of negative pressure during at a high speed by undergauge pipe section in chamber, rear flank.