CN102745852A

CN102745852A - Brine-desalination method

Info

Publication number: CN102745852A
Application number: CN2012102480856A
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: 2012-10-24
Anticipated expiration: 2032-07-18
Also published as: CN102745852B

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

Increase, can supply in mass development and the process of industrialization of the human water resources of directly utilizing pollution to the used water resource along with world population; Tellurian Freshwater resources reduce day by day and worsen; The drinkable water distribution of resource is also very uneven; In order to tackle the deficient situation of Freshwater resources, various places all attempt utilizing local used water resource to adopt various treatment technologies to produce fresh water, and using maximum is the processing of sea water desaltination, brackish water desalination and high density salt solution.

At present; The saline-water reclamation method mainly contains distillation method, cold method, ion exchange method and embrane method, the development of desalination techniques mainly round cut down the consumption of energy with cost be purpose, distillation method has multiple-effect evaporation, MSF etc.; Cold method is because energy consumption is big; Mainly utilize the natural cooling source in winter to realize, ion exchange method has electro-adsorption, electrodialysis etc., and embrane method mainly contains nf membrane, ultra-filtration membrane, reverse osmosis membrane, electrodialysis (ion-exchange membrane).The distillation method principle is simple, but energy consumption is big, uses low-temperature evaporation effectively to cut down the consumption of energy, and along with the development of film production technology, embrane method desalination brinish cost has become the most competitive saline-water reclamation process.

The present invention organically combines distillation method and embrane method; The negative pressure of utilizing the high drive Venturi squirt pump of the strong brine side of embrane method to produce reduces follow-up evaporating pressure, and evaporative process is carried out being lower than under the normal atmosphere, can effectively reduce vaporization temperature; Increase the additional issue amount; Practice thrift the evaporation energy consumption, make the concentration of evaporation raffinate higher, utilize 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; Distillation method and embrane method that this method will be used for brine desalination organically combine, and utilize the negative pressure of high drive Venturi squirt pump of the strong brine side of embrane method to reduce follow-up evaporating pressure, and evaporative process is carried out being lower than under the normal atmosphere; Can effectively reduce vaporization temperature; Practice thrift the evaporation energy consumption, make the concentration of evaporation raffinate higher, utilize 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) get into after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, security personnel's strainer pre-treatment (2) then through topping-up pump 4, gets into membrane treatment appts (5) and carries out membrane filtration, obtains film and handles water purification (14);

B, the water purification (14) after film is handled come into operation, and remain dense water and go out the moisture two-way, and one the tunnel gets into the Venturi squirt pump penetrates at a high speed; Tank (3) circular treatment in the middle of getting into; Another road behind interchanger (15) and well heater (8) heat temperature raising, gets into cryogenic vaporizer (10) through throttling valve (9) through non-return valve (7); Steam is condensed after interchanger (15) is with the heat transferred strong brine, gets into distillation water pot (11);

The strong brine that comes out in c, cryogenic vaporizer (10) bottom gets into crystallization apparatus (12) and isolates salt (17) and water, evaporates a part of water vapor recovery entering distillation water pot (11) that and can obtain zero(ppm) water (16).

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

Membrane treatment appts among the said step a (5) is nf membrane or reverse osmosis membrane processing device, and the use of these two kinds of films all needs bigger force.

The Venturi squirt pump is that high pressure fluid produces means for applying negative at a high speed when the undergauge pipe section in the chamber, rear flank among the said step b.

The method of a kind of water desalination of the present invention; The characteristics of this method are: utilize the pressure ability of the strong brine side of membrane treatment appts, drive the Venturi water jet pump and produce negative pressure, the evaporative process of strong brine is carried out under negative pressure; Reduced the vaporization temperature of water; Reduced heating brinish energy consumption, the latent heat of vaporization of utilizing water vapor condensation to emit simultaneously heats strong brine to be evaporated, effectively reduces the cost of salt solution concentrating and separating.Different according to raw water quality in former water pretreatment, preprocessing process can adjust accordingly, and purpose is to satisfy the water quality requirement that gets into membrane treatment appts.

Description of drawings

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

Embodiment

Embodiment 1

A, salt solution 1 got into after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, security personnel's strainer pre-treatment 2 in the middle of tank 3, then through topping-up pump 4, get into reverse osmosis membrane processing device 5 and carry out membrane filtration, obtain film and handle water purification 14;

B, the water purification 14 after film is handled can store or come into operation, and the residue strong brine goes out the moisture two-way, and one the tunnel gets into the Venturi squirt pump penetrates at a high speed; Tank 3 circular treatment in the middle of getting into; Another road is through non-return valve 7 (preventing that the pipeline inner fluid from flowing backwards), and (heating unit 8 can adopt various forms of process furnace for the evaporation of water vapor provides heat energy behind interchanger 15 and well heater 8 heat temperature raisings; Power plant with good conditionsi can use waste hot steam as thermal source; The competent place of illumination can use sun power that thermal source is provided, like solar water heater), through the throttling valve 9 (effect of salt solution decompression in playing to pipeline; So that after the salt solution decompression; Obtain bigger steam output) get into 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 being lower than under the boiling point situation of water; Steam is condensed (interchanger 15 is used to reclaim the water vapor condensation liberated heat that is evaporated and comes preheating salt solution to be evaporated) after interchanger 15 is with the heat transferred strong brine, get into distillation water pot 11;

The strong brine that comes out in c, cryogenic vaporizer 10 bottoms gets into crystallization apparatus 12 strong brine is separated into salt 17 and water; Evaporate a part of water vapor recovery entering distillation water pot 11 that and to obtain zero(ppm) 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 present embodiment is handled is brackish water, can be used for long area of sunshine duration.

A, brackish water 1 got into after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, security personnel's strainer pre-treatment 2 in the middle of tank 3, then through topping-up pump 4, get into reverse osmosis membrane processing device 5 and carry out membrane filtration, obtain film and handle water purification 14;

B, the water purification after film is handled 14 store or come into operation; The residue strong brine goes out the moisture two-way; One the tunnel gets into the Venturi squirt pump penetrates at a high speed, tank 3 circular treatment in the middle of getting into, and another road is through non-return valve 7 (preventing that the pipeline inner fluid from flowing backwards); Behind interchanger 15 and well heater 8 (here being solar water heater) heat temperature raising; Get into cryogenic vaporizer 10 through throttling valve 9 (effect of salt solution decompression in playing to pipeline is so that after the salt solution decompression, obtain bigger steam output); 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 being lower than under the boiling point situation of water, and steam is condensed (interchanger 15 is used to reclaim the water vapor condensation liberated heat that is evaporated and comes preheating salt solution to be evaporated) after interchanger 15 is with the heat transferred strong brine, gets into distillation water pot 11;

Embodiment 3

The former water that present embodiment is handled is seawater;

A, seawater (1) got into after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, security personnel's strainer pre-treatment (2) in the middle of tank (3), then through topping-up pump 4, get into nanofiltration membrane treatment device (5) and carry out membrane filtration, obtain film and handle water purification 14;

B, the water purification 14 after film is handled come into operation, and the residue strong brine goes out the moisture two-way, and one the tunnel gets into the Venturi squirt pump penetrates at a high speed; Tank 3 circular treatment in the middle of getting into; Another road prevents that through non-return valve 7 the pipeline inner fluid from flowing backwards, and (heating unit 8 can adopt various forms of process furnace for the evaporation of water vapor provides heat energy behind interchanger 15 and well heater 8 heat temperature raisings; Power plant with good conditionsi can use waste hot steam as thermal source; The competent place of illumination can use sun power that thermal source is provided, like solar water heater), through the throttling valve 9 (effect of salt solution decompression in playing to pipeline; So that after the salt solution decompression; Obtain bigger steam output) get into 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 being lower than under the boiling point situation of water; Steam is condensed (interchanger 15 is used to reclaim the water vapor condensation liberated heat that is evaporated and comes preheating salt solution to be evaporated) after interchanger 15 is with the heat transferred strong brine, get into distillation water pot 11;

The strong brine that comes out in c, cryogenic vaporizer 10 bottoms gets into crystallization apparatus 12 strong brine is separated into salt 17 and water; Evaporate a part of water vapor that and reclaim entering distillation water pot 11; Can obtain zero(ppm) 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. 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) get into after mechanical removal of impurities filtration, micro-filtration, ultrafiltration, security personnel's strainer pre-treatment (2) then through topping-up pump (4), gets into membrane treatment appts (5) and carries out membrane filtration, obtains film and handles water purification (14);

B, the water purification (14) after film is handled come into operation, and the residue strong brine goes out the moisture two-way, and one the tunnel gets into the Venturi squirt pump penetrates at a high speed; Tank (3) circular treatment in the middle of getting into; Another road behind interchanger (15) and well heater (8) heat temperature raising, gets into cryogenic vaporizer (10) through throttling valve (9) through non-return valve (7); Steam is condensed after interchanger (15) is with the heat transferred strong brine, gets into distillation water pot (11);

2. method according to claim 1 is characterized in that said step a Central Plains water (1) is brackish water or salt solution or seawater.

3. method according to claim 1 is characterized in that membrane treatment appts among the said step a (5) is nf membrane or reverse osmosis membrane processing, and the use of these two kinds of films all needs bigger force.

4. method according to claim 1 is characterized in that among the said step b that the Venturi squirt pump is that high pressure fluid produces means for applying negative during at a high speed through the undergauge pipe section in the chamber, rear flank.