CN101224391A - Water curing reverse osmosis membrane chemical cleaning method - Google Patents

Abstract

The invention relates to a chemical cleaning method used for a water disposal reverse osmosis membrane, relating to a chemical cleaning method used for cleaning water disposal reverse osmosis membranes in the industrial water disposal process. The invention is characterized in that NaOH solution which contains EDTA is adopted to clean microorganism, organism and silicon dioxide, etc. pollutants on the reverse osmosis membrane; HCI solution is adopted to clean calcium bicarbonate and magnesium bicarbonate filth on the reverse osmosis membrane. By adopting the method of the invention, the reverse osmosis membrane used by captive power plant water disposal can be effectively cleaned in the alumina preparation process. The invention has better cleaning effect, reliable and practiced technique and convenient operation process.

Description

A kind of water curing reverse osmosis membrane chemical cleaning method

Technical field

A kind of water curing reverse osmosis membrane chemical cleaning method relates to the chemical cleaning method of the water treatment reverse osmosis membrane in a kind of treatment of industrial water.

Background technology

In treatment of industrial water, the reverse osmosis membrane surface is in operation owing to the pollution of bringing material into of feeding water produces dirt, for example: contained microorganism in the former water; Unboiled water water quality silt pollution; The hydrate of metal oxide, the sediment of calcium, organic matter etc., when the reverse osmosis membrane dirt is stifled, its aquifer yield, salt rejection rate, the rate of recovery obviously descend, when serious, counter-infiltration can't put into operation, cause to produce and be forced to stop, even preliminary treatment is reasonable in design, the operation normal, general year counter-infiltration half a year to one need be cleaned once.Cleaning relies on the professional of producer usually and finishes, but is subjected to many effects limit such as time, space, equipment, condition, and the clear Xian Changchang of specialty has very big hysteresis quality, production is caused seriously influence, and clear Xian's expense height.

Summary of the invention

Purpose of the present invention is exactly the deficiency that exists at above-mentioned prior art, provides a kind of and is not produced, technology, equipment, time, spatial constraints, can effectively solve the water curing reverse osmosis membrane chemical cleaning method of processing procedure hysteresis quality problem.

The objective of the invention is to be achieved through the following technical solutions.

A kind of water curing reverse osmosis membrane chemical cleaning method is characterized in that adopting the NaOH solution that contains EDTA that the pollutant of the microorganism on the reverse osmosis membrane, organic matter and silica is cleaned; Adopt HCL solution that the calcium bicarbonate on the reverse osmosis membrane, bicarbonate magne-scale are cleaned.

A kind of water curing reverse osmosis membrane chemical cleaning method of the present invention is characterized in that the pH value of described NaOH solution is 11-12, contains the EDTA that weight ratio is 0.5%-1% in the solution.

A kind of water curing reverse osmosis membrane chemical cleaning method of the present invention is characterized in that the pH value of described HCL solution is 2-3.

A kind of water curing reverse osmosis membrane chemical cleaning method of the present invention is characterized in that cleaning process is followed successively by:

(1) cleaning fluid injects: in temperature is that 25-30 ℃, pressure are under the 0.1-0.15MPa condition, the control flow be normal discharge half inject cleaning fluid;

(2) wash cycles: in temperature is 25-30, and pressure is to carry out repeatedly wash cycles under the 0.1-0.15MPa condition 60 minutes; Pressure is controlled to be product water side does not have penetrating fluid;

(3) soak: soaked 1-15 hour;

(4) clean: at normal temperature, pressure is that 0.35MPa, flow are under the normal discharge 1-1.5 times condition, cleans 30-60 minute;

(5) wash out cleaning fluid: at normal temperature, pressure is under 0.35MPa, the condition, and reverse osmosis produced water or ultrafiltration are produced water and washed out cleaning fluid.

A kind of water curing reverse osmosis membrane chemical cleaning method of the present invention, when cleaning microbial film, organic matter and silica to the pollution of reverse osmosis membrane, adopt NaOH+EDTA solution, wherein is furnished with the part chelating agent, dirt ions such as calcium, magnesium, iron all there is the effect of complexing, under pH value 11-12 condition, can remove part calcium bicarbonate, bicarbonate magne-scale and peel off microorganism mucous membrane, organic matter etc., play the effect of associated treatment.Employing HCL cleans carbonate deposit under pH value 2-3 condition, most metal oxide causes dirty stifled.Its cleaning process is identical with step.

During cleaning, the water treatment reverse osmosis equipment is opened one section dense water side cleaning valve and penetrating fluid return valve fully, open one section cleaning fluid inlet valve, close other valve of corresponding unit.

Low discharge advances medicine: start the counter-infiltration chemical cleaning pump, slowly regulate security personnel's filter outlet door and control flow with outlet valve, inject cleaning fluid with low discharge, and, clean with only enough compensating the pressure that concentrates the pressure drop of water outlet from intaking to the surplus water in the low pressure eliminating pressure vessel.This pressure should be lower than and not produce penetrating fluid substantially and be advisable, low pressure can make concentrate on film again deposition reduce to minimum, be absolutely necessary for preventing that cleaning fluid is diluted.

Wash cycles repeatedly: cleaning fluid will exist with the fluidised form of concentrate and the two kinds of forms of form that see through liquid, and these two kinds of liquid that circulate repeatedly are to the cleaning fluid water tank.Behind the circulation certain hour, the concentration and the pH value of cleaning fluid surveyed in sampling, if pH value changes about 0.5, then should add reagent and regulate, if cleaning fluid is too muddy, then should prepare cleaning fluid again.

Soak: close scavenging pump, cleaning unit is soaked.Generally speaking, soak time be 1 hour enough, decide with regard to pollution condition, if reverse osmosis membrane is seriously polluted, then should be immersed in about 10-15 hour, between the soak period of long period, if the counter-infiltration rinse liquid temperature descends, need with the slower higher cleaning fluid of circular flow implantation temperature, keeping constant soaking temperature that counter-infiltration is cleaned is of great benefit to.When soaking, also can adopt the oscillatory type douche.

Big flow cleaning: advance medicine and cleaning 30-60 minute under the prerequisite of big flow, 8 inches film flows are the membrane component number that 9.1m3/h multiply by cleaning section.

Wash out cleaning fluid: after one section, two sections cleanings finish, close the cleaning fluid terminal valve, open the flush discharge door, adopt water tank with strainer water to carry out rinsing 15-30 minute, the length of time is foundation with the pH value of flushing water water sample, electrical conductivity etc. mainly.This process can be cleaned the dirt that peels off effectively.

Two kinds and two or more liquid formulas are taked in cleaning, after original liquid must being rinsed well, begin to clean with another kind of soup again.

Dynamically clean and under certain flow velocity, rely on its kinetic energy can help dirt to wash away and peel off, when static for peel off with the dissolving of having an opportunity again of place, unpeeled dead angle, the effect that sound replaces is indubitable.

Reverse osmosis unit after the cleaning should be earlier emits the product water of initial operating stage when bringing into operation, and drain time was at least 10 minutes.

Adopt method of the present invention, can carry out effectively clear Xian to the private station Water Treatment counter-infiltration in the aluminum oxide production process, clear Xian is respond well, and technology maturation is reliable, and is easy to operate.Employing exports the check flip chip technology with high-pressure pump, successfully the stifled security personnel's filter element of dirt is cleaned, and has prolonged the service life of security personnel's filter elements, has reduced production cost.

The specific embodiment

A kind of water curing reverse osmosis membrane chemical cleaning method adopts the NaOH solution that contains EDTA that the pollutant that causes because of microorganism, organic matter and silica etc. on the reverse osmosis membrane is cleaned; Adopt HCL solution to cleaning because of dirty things such as calcium bicarbonate, magnesium bicarbonates on the reverse osmosis membrane.The pH value of described NaOH solution is 11-12, contains the EDTA that weight ratio is 0.5%-1% in the solution.The pH value of described HCL solution is 2-3.Cleaning process is followed successively by:

(1) cleaning fluid injects: in temperature is that 25-30 ℃, pressure are under the 0.1-1MPa condition, the control flow be normal discharge half inject cleaning fluid;

(2) wash cycles: in temperature is 25-30, and pressure is to carry out repeatedly wash cycles under the 5MPa condition 60 minutes; Pressure is controlled to be product water side does not have penetrating fluid;

(3) soak: soaked 1-15 hour;

(4) clean: at normal temperature, pressure is that 0.35MPa, flow are under the normal discharge 1-1.5 times condition, cleans 30-60 minute;

(5) wash out cleaning fluid: at normal temperature, pressure is under 0.35MPa, the condition, produces water with reverse osmosis produced water or ultrafiltration and washes out cleaning fluid.

Embodiment 1

The NaOH solution that employing contains EDTA cleans the pollutant of the microorganism on the reverse osmosis membrane, organic matter and silica; Adopt HCL solution that the calcium bicarbonate on the reverse osmosis membrane, bicarbonate magne-scale are cleaned.The pH value of NaOH solution is 11 in the clear clear process, contains weight ratio in the solution and be 0.5% EDTA.The pH value of described HCL solution is 2.Its cleaning process is followed successively by:

(1) cleaning fluid injects: in temperature is that 25 ℃, pressure are under the 0.1MPa condition, the control flow be normal discharge half inject cleaning fluid;

(2) wash cycles: in temperature is 25 ℃, and pressure is to carry out repeatedly wash cycles under the 0.1-0.15MPa condition 60 minutes; Pressure is controlled to be product water side does not have penetrating fluid;

(3) soak: soaked 1-15 hour;

(4) clean: at normal temperature, pressure is that 0.35MPa, flow are under the normal discharge 1-1.5 times condition, cleans 60 minutes;

(5) wash out cleaning fluid: at normal temperature, pressure is under 0.35MPa, the condition, washes out cleaning fluid with ultrafiltration product water or counter-infiltration.

Embodiment 2

A kind of water curing reverse osmosis membrane chemical cleaning method, the pH value of NaOH solution is 12, contains weight ratio in the solution and be 1% EDTA.The pH value of described HCL solution is 3.Its cleaning process is followed successively by:

(1) cleaning fluid injects: in temperature is that 30 ℃, pressure are under the 0.15MPa condition, the control flow be normal discharge half inject cleaning fluid;

(2) wash cycles: in temperature is 30 ℃, and pressure is to carry out repeatedly wash cycles under the 0.1-0.15MPa condition 60 minutes; Pressure is controlled to be product water side does not have penetrating fluid;

(3) soak: soaked 1-15 hour;

(4) clean: at normal temperature, pressure is that 0.35MPa, flow are under the normal discharge 1-1.5 times condition, cleans 30 minutes;

(5) wash out cleaning fluid: at normal temperature, pressure is under 0.35MPa, the condition, washes out cleaning fluid with ultrafiltration product water or counter-infiltration.

Claims (4)

1. water curing reverse osmosis membrane chemical cleaning method is characterized in that adopting the NaOH solution that contains EDTA that the pollutant of the microorganism on the reverse osmosis membrane, organic matter and silica is cleaned; Adopt HCL solution that the calcium bicarbonate on the reverse osmosis membrane, bicarbonate magne-scale are cleaned.

2. a kind of water curing reverse osmosis membrane chemical cleaning method according to claim 1 is characterized in that the pH value of described NaOH solution is 11-12, contains the EDTA that weight ratio is 0.5%-1% in the solution.

3. a kind of water curing reverse osmosis membrane chemical cleaning method according to claim 1 is characterized in that the pH value of described HCL solution is 2-3.

4. a kind of water curing reverse osmosis membrane chemical cleaning method according to claim 1 is characterized in that cleaning process is followed successively by:

(1) cleaning fluid injects: in temperature is that 25-30 ℃, pressure are under the 0.1-0.15MPa condition, the control flow be normal discharge half inject cleaning fluid;

(2) wash cycles: in temperature is 25-30, and pressure is to carry out repeatedly wash cycles under the 5MPa condition 60 minutes; Pressure is controlled to be product water side does not have penetrating fluid;

(3) soak: soaked 1-15 hour;

(4) clean: at normal temperature, pressure is that 0.35MPa, flow are under the normal discharge 1-1.5 times condition, cleans 30-60 minute;

(5) wash out cleaning fluid: at normal temperature, pressure is under 0.35MPa, the condition, produces water with reverse osmosis produced water or ultrafiltration and washes out cleaning fluid.