CN-116550146-B - Reverse osmosis membrane device and method for recycling finishing liquid

CN116550146BCN 116550146 BCN116550146 BCN 116550146BCN-116550146-B

Abstract

The invention discloses a reverse osmosis membrane device for recovering finishing liquid, which comprises a finishing liquid concentration and recovery device and a drawing liquid regeneration device, wherein the finishing liquid concentration and recovery device comprises a water inlet circulation tank, a water inlet circulation pump, a finishing liquid concentration and retraction membrane component, a drawing liquid circulation pump and a drawing liquid circulation tank, the drawing liquid regeneration device adopts two-stage reverse osmosis treatment, the invention also discloses a method for recovering the finishing liquid, the finishing liquid concentration and recovery device utilizes the osmotic pressure and the water inlet pressure of the drawing liquid to separate the finishing liquid from water, so that the finishing liquid is concentrated, the drawing liquid is recycled after being regenerated through the reverse osmosis membrane, and produced water is used as desalted water for recycling. The tubular reverse osmosis membrane component adopted by the invention has higher interception rate of finishing liquid, stronger pollution resistance and easy cleaning and replacement.

Inventors

JIANG WEN
LI DONGJIANG
LI WU
PENG WEI
GU ZHENG
YANG DEYU
WANG LEI
MIAO XIAOQING
ZHAO YANQI

Assignees

中钢集团武汉安全环保研究院有限公司

Dates

Publication Date: 20260508
Application Date: 20230531

Claims (8)

1. A method for recovering a finishing liquid, which uses a reverse osmosis membrane device for recovering a finishing liquid, is characterized by comprising a treatment step for lower concentration of the finishing liquid to be recovered and a treatment step for higher concentration of the finishing liquid to be recovered, The reverse osmosis membrane device for recycling the finishing liquid comprises a water inlet circulation box (1), wherein a water outlet of the water inlet circulation box (1) is communicated with a finishing liquid water inlet (21) of a finishing liquid concentration and recovery membrane assembly (3) through a water inlet circulation pump (2), a finishing liquid water outlet (28) of the finishing liquid concentration and recovery membrane assembly (3) is communicated with a water inlet of the water inlet circulation box (1), a first water outlet of a drawing liquid circulation box (5) is communicated with a drawing liquid water inlet (23) of the finishing liquid concentration and recovery membrane assembly (3) through a drawing liquid circulation pump (4), and a drawing liquid water outlet (26) of the finishing liquid concentration and recovery membrane assembly (3) is connected with a water inlet of the drawing liquid circulation box (5); The second water outlet of the drawing liquid circulation box (5) is sequentially connected with the water inlet of the first-stage water inlet pump (6) and the booster pump (7) and the water inlet of the first-stage drawing liquid regeneration membrane assembly (9), the concentrated water inlet of the first-stage drawing liquid regeneration membrane assembly (9) is respectively connected with the water inlet of the drawing liquid circulation box (5) and the water inlet of the first-stage circulation pump (8), the water outlet of the first-stage circulation pump (8) is connected with the water inlet of the first-stage drawing liquid regeneration membrane assembly (9), and the water outlet of the first-stage drawing liquid regeneration membrane assembly (9) is connected with the water inlet of the first-stage water production box (10); The water outlet of the primary water production tank (10) is connected with the water inlet of the secondary drawing liquid regeneration membrane assembly (13) through the secondary water inlet pump (11), the concentrated water port of the secondary drawing liquid regeneration membrane assembly (13) is respectively connected with the water inlet of the drawing liquid circulation tank (5) and the water inlet of the secondary circulation pump (12), the water outlet of the secondary circulation pump (12) is connected with the water inlet of the secondary drawing liquid regeneration membrane assembly (13), and the water outlet of the secondary drawing liquid regeneration membrane assembly (13) is connected to the secondary water production tank (14); The membrane module (3) is a tubular reverse osmosis membrane module, the diameter of a single membrane tube of a membrane tube bundle (25) of the membrane module (3) is 6-8 mm, a polyamide composite membrane is adopted as a filtering material of the membrane tube, the length of the membrane tube is 1-3 m, the flow rate in the membrane tube is 1-2 m/s, and the running pressure in the membrane tube is 0.2-0.5 mpa; the treatment step for the lower concentration of the finishing liquid to be recovered comprises the following steps: The method comprises the steps of 1.1, the initial state in a drawing liquid circulation box (5) is empty, a drawing liquid circulation pump (4), a primary water inlet pump (6), a booster pump (7), a primary circulation pump (8), a secondary water inlet pump (11) and a secondary circulation pump (12) are closed, and a water inlet circulation pump (2) is opened; when the conductivity of the finishing liquid in the water inlet circulation tank (1) reaches a preset concentration, discharging the finishing liquid in the water inlet circulation tank (1) to a finishing liquid storage tank, re-entering the low-concentration finishing liquid in the water inlet circulation tank (1), monitoring the conductivity in the drawing liquid circulation tank (5), and when the water yield in the drawing liquid circulation tank (5) is greater than 10 mu S/cm, starting a primary water inlet pump (6), a booster pump (7) and a primary circulation pump (8), wherein the water inlet circulation pump (2) is kept on, and the drawing liquid circulation pump (4), a secondary water inlet pump (11) and a secondary circulation pump (12) are kept off; aiming at the treatment step of higher concentration of the finishing liquid to be recovered: And 2.1, the drawing liquid circulation tank (5) is filled with the drawing liquid, the drawing liquid circulation pump (4), the secondary water inlet pump (11), the secondary circulation pump (12), the water inlet circulation pump (2), the primary water inlet pump (6), the booster pump (7) and the primary circulation pump (8) are all started, when the conductivity of the finishing liquid in the water inlet circulation tank (1) reaches the preset concentration, the finishing liquid in the water inlet circulation tank (1) is discharged to the finishing liquid storage tank, and the finishing liquid with low concentration is reentered in the water inlet circulation tank (1).
2. The method for recycling finishing liquid according to claim 1, wherein the finishing liquid concentration recycling membrane assembly (3) comprises a cylindrical membrane shell (24), a membrane tube bundle (25) is arranged in the membrane shell (24), two ends of the membrane shell (24) are open and are respectively a water outlet open end and a water inlet open end, the water outlet open end is connected with a water outlet end cover (32), the water inlet open end is connected with a water inlet end cover (31), a finishing liquid water outlet (28) and a finishing liquid water inlet (21) are respectively arranged at the centers of the water outlet end cover (32) and the water inlet end cover (31), a water outlet packaging end (27) and a water inlet packaging end (22) are respectively arranged at two ends of the membrane tube bundle (25), wherein the water outlet packaging end (27) is close to the water outlet open end, the water inlet packaging end (22) is close to the water inlet open end, a drawing liquid water outlet (26) is arranged on the side wall of the membrane shell (24) close to the water outlet open end, and a drawing liquid water inlet (23) is arranged on the side wall of the membrane shell (24) close to the water inlet open end.
3. A method for recovering a polishing liquid according to claim 2, characterized in that the outer wall of the water inlet end cap (31) and the outer wall of the membrane shell (24) are detachably connected by a plurality of water inlet end clamps (30), and the outer wall of the water outlet end cap (32) and the outer wall of the membrane shell (24) are detachably connected by a plurality of water outlet end clamps (29).
4. A method for recovering a polishing liquid according to claim 2, wherein the membrane bundle (25) is a tubular reverse osmosis membrane.
5. A method for recovering a polishing liquid according to claim 4, wherein the in-line conductivity meter is arranged in each of the water inlet circulation tank (1), the drawing liquid circulation tank (5), the primary water production tank (10) and the secondary water production tank (14).
6. A method for recovering a finishing liquid according to claim 5, characterized in that the pipes of the finishing liquid inlet (21), the finishing liquid outlet (28), the drawing liquid inlet (23) and the drawing liquid outlet (26) are provided with pressure sensors and flow meters.
7. The method for recycling finishing liquid according to claim 6, wherein the drawing liquid adopted by the drawing liquid circulation box (5) is sodium chloride solution, and the concentration of the sodium chloride solution is 20-30 g/L.
8. The method for recycling finishing liquid according to claim 7, wherein the primary drawing liquid regeneration membrane assembly (9) and the secondary drawing liquid regeneration membrane assembly (13) adopt coiled reverse osmosis membranes, the operation pressure of the primary drawing liquid regeneration membrane assembly (9) is 3-4 mpa, the water production conductivity is lower than 300 μs/cm, the operation pressure of the secondary drawing liquid regeneration membrane assembly (13) is 0.6-1.0 mpa, and the water production conductivity is lower than 10 μs/cm.

Description

Reverse osmosis membrane device and method for recycling finishing liquid Technical Field The invention relates to the technical field of membrane separation, in particular to a reverse osmosis membrane device for recovering finishing liquid. Background With the development of membrane materials and membrane technologies, membrane separation technologies are widely used as novel water treatment technologies in the fields of sewage treatment such as biology, chemical industry, medicine, food, municipal administration and the like. The membrane separation technology has become the preferential choice for the improvement of the waste water upgrading and the reuse of reclaimed water. The separation principle of the traditional membrane technology is to select a specific membrane as a separation medium according to the size and the type of the separated matters, and the matters are selectively penetrated under the action of pushing force to achieve the purpose of separation. The membrane can be divided into a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane and a reverse osmosis membrane according to the size of the pore diameter, a symmetrical membrane, an asymmetrical membrane and a composite membrane according to the different structures, a roll-type membrane, a flat membrane, a hollow fiber membrane, a tubular membrane and the like according to the appearance. The reverse osmosis membrane component generally adopts a roll-type structure, has higher requirements on water inflow in water treatment, is easy to block and has short service life, and the characteristics limit the application of the reverse osmosis membrane component. The tubular membrane component has large adjustable range of the flow velocity of the feed liquid, easy control of concentration polarization, easy cleaning and replacement of the membrane component, and simpler pretreatment requirements on the feed liquid, but is only applicable to water treatment systems with high concentration and high solid content. The finishing liquid belongs to the technical field of material surface treatment and is generally used as a metal surface treating agent. The effective components of the finishing liquid generally comprise a composite antirust agent, a corrosion inhibitor, a surfactant, a lubricant, a composite additive, a bactericide, a solubilization auxiliary agent, a pH regulator and the like. Wherein the compound antirust agent is usually polybasic acid, organic amine, etc., such as phosphoric acid, boric acid, sebacic acid, alcohol amine, carboxylic acid amine, etc. The corrosion inhibitor is thiazole derivatives such as tolyltriazole and benzotriazol. The surfactant is generally vinyl ether. The lubricant is fatty alcohol phosphate or polyether ester. In order to improve the service efficiency of the membrane and prolong the service life of the membrane in application, the membrane assembly which has strong anti-pollution performance, is easy to clean, is difficult to generate concentration polarization in the membrane assembly and is convenient to maintain needs to be designed. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a reverse osmosis membrane device for recovering a finishing liquid, which solves the problems in the prior art. In order to achieve the above purpose, the present invention provides the following technical solutions: The reverse osmosis membrane device for recovering the finishing liquid comprises a water inlet circulation tank, wherein a water outlet of the water inlet circulation tank is communicated with a finishing liquid water inlet of a finishing liquid concentration and recovery membrane assembly through a water inlet circulation pump, a finishing liquid water outlet of the finishing liquid concentration and recovery membrane assembly is communicated with a water inlet of the water inlet circulation tank, a first water outlet of a drawing liquid circulation tank is communicated with a drawing liquid water inlet of the finishing liquid concentration and recovery membrane assembly through a drawing liquid circulation pump, and a drawing liquid water outlet of the finishing liquid concentration and recovery membrane assembly is connected with a water inlet of the drawing liquid circulation tank; The second water outlet of the drawing liquid circulation tank is sequentially connected with the water inlet of the first-stage water inlet pump, the booster pump and the water inlet of the first-stage drawing liquid regeneration membrane assembly, the concentrated water inlet of the first-stage drawing liquid regeneration membrane assembly is respectively connected with the water inlet of the drawing liquid circulation tank and the water inlet of the first-stage circulation pump, the water outlet of the first-stage circulation pump is connected with the water inlet of the first-stage drawing liquid regeneration membrane assembly, and the water