Special cleaning method for reverse osmosis seawater desalination equipment
Reverse flow cleaning
Reverse cleaning is particularly effective for membrane assemblies contaminated by corrosive products and sludge, which are mostly deposited on the feed inlet side.
The specific method is to connect the cleaning liquid infusion pipe to the RO section of concentrated water outlet, and connect the cleaning liquid discharge pipe to the RO section of the inlet. Alternate positive and negative flushing is also effective for sludge - contaminated membrane assemblies.
Each running time is about 30s~3min.
Manifolds and valves should be provided to reduce refining if reversing frequently
Reverse cleaning can also be used for RO production water washing membrane components, cleaning fluid prepreg, etc., to improve the cleaning effect.
For hollow fiber RO modules, as the fiber is pushed to the distribution pipe during the backwashing process, the velocity of cleaning fluid is less than the velocity of washing, the velocity should be recorded, and the pressure of cleaning fluid should be limited below 0.35mpa.
Reverse osmosis equipment cleaning management measures
The composition of the reverse osmosis equipment:
1. The pretreatment is usually composed of a quartz sand filter device, an activated carbon filter device and a precision filter device. The main purpose is to remove sediment, rust, colloidal substances, suspended solids, pigments, odors, biochemical organic matter, and reduce moisture in raw water.
Residual ammonia and pesticides and other harmful substances.
If the calcium and magnesium ions in the raw water are high, a soft water device is required. The main purpose is to protect the reverse osmosis membrane of the latter stage from the destruction of large particulate matter, thereby extending the service life of the reverse osmosis membrane.
2. The reverse osmosis main engine is mainly composed of a booster pump, a membrane shell, a reverse osmosis membrane, a control loop, etc., and is a core part of the entire water treatment system. The quality of the produced water depends mainly on this part.
As long as the model of the membrane and the model of the booster pump are selected, the reverse osmosis unit can achieve a salt filtration capacity of more than 99 in the water and ensure that the conductivity of the effluent is within 10 us / cm 25 degrees.
3. The post-treatment part is mainly to further treat the pure water taken by the main mechanism of reverse osmosis. If the subsequent process is connected to an ion exchange or electrodeionization EDI unit, it can produce ultrapure water for industrial use.
In the drinking water process, the rear sterilization device is often connected, for example, an external germicidal lamp or an ozone generator can be connected so that the water can be directly consumed.
4. In order to ensure the normal operation of the reverse osmosis system and prolong the service life of the reverse osmosis membrane element, it is necessary to remove the calcium carbonate scale and the metal oxide scale after the reverse osmosis system is operated for a period of time. Water, biological growth bacteria, fungi, molds, etc.
The system must be cleaned.
Reverse osmosis equipment cleaning management method:
1, low pressure flushing
Routine Low Pressure Flushing the reverse osmosis unit in accordance with maintenance regulations helps remove stains attached to the reverse osmosis membrane and maintains membrane stability.
2, stop using protection
For reasons of production, reverse osmosis equipment often needs to be shut down, which will affect the performance of the reverse osmosis membrane. In severe cases, performance will be lost and cannot be recovered.
Low pressure flushing can be used to reduce the effects of short-term power outages.
It is worth noting that the temperature of the water used for rinsing should not be too low, otherwise it will affect the reverse osmosis membrane and cause deterioration and spoilage of the membrane.
Long-term power outages must be cleaned and protected with a biocide.
3. Chemical cleaning reverse osmosis membrane
Under normal conditions, substances attached to the reverse osmosis membrane, such as inorganic substances, microorganisms and metal oxides, may reduce the processing capacity of the reverse osmosis membrane and cause fatal failure.
In order to maintain the water permeability and desalination effect of the reverse osmosis membrane, the reverse osmosis membrane should be chemically cleaned. Application range of reverse osmosis equipment
Common techniques and applications of reverse osmosis equipment:
The reverse osmosis device is manufactured according to the principle opposite to the permeation phenomenon. Essentially, the pressure of the solution is made greater than the osmotic pressure so that the water in the solution separates through the semipermeable membrane.
It removes harmful substances such as bacteria from the water.
Common techniques for reverse osmosis equipment:
1, quartz sand + activated carbon + softening + safety filter + reverse osmosis equipment host
2, quartz sand + activated carbon + scale inhibition system + safety filter + reverse osmosis equipment host
3, flocculation sedimentation + quartz sand + activated carbon + scale inhibition system + safety filter + reverse osmosis equipment host
4, quartz sand + activated carbon + softening + safety filter + reverse osmosis device + ozone sterilization / UV sterilization
5, quartz sand + activated carbon + softening + safety filter + first-grade reverse osmosis + two-stage reverse osmosis + ozone sterilization / ultraviolet sterilization
6, ceramic membrane filter + softening + safety filter + reverse osmosis device + ozone sterilization / UV sterilization