1. Deionized water production line Technical processes:
Tap water→Original pump→Quartzite filter→Active carbon filter→Security filter→First class high-pressure pump→First calss RO→RO water producing tank
2. Deionized water production line Pre-treatment system:
2.1 The purpose of treatment raw water is to solve following problems:
Prevent membrane surface fouling (CaCO3, CaSO4, SrSO4, SiO2, Fe-Al-oxide);
Prevent colloidal substances and suspended solid particles fouling;
Prevent fouling of organic matter;
Prevent microbial fouling;
Prevent oxidizing substances cause oxidation damage to membrane;
Maintain water production capacity remain stable of reverse osmosis device;
In order to ensure the stable operation and service life-span of reverse osmosis device.
The reverse osmosis system water after pre-treatment should meet following requirements:
|Silt density index||SDI≤5
|Water temperature suitable range||5～45℃
|Concentrate water saturation index LSI||<0
2.2 Raw water pressure device
In order to ensure this system water flow and pressure stability, there set up a raw water pressure pump.
2.3 Multi-media filter
Multi-media filter is used to remove particulate impurities, swim suspended matter and organic matter, to make sure subsequent processes normal operation. This system set up a diameter: 1200mm vertical multi-media filter, while inside the filter fill in with purified quartz sand which has well graded, the filter layer height as height of the filter is 1200mm-1600mm, the after treating water greatly reducing SDI and turbidity values, and usually can make the outlet water SDI <3, turbidity <1NTU. Filter backwash to control backwash cycle based on flow rate or time parameters, when the pressure difference reach the set value on inlet and outlet water mother tube then need to backwash.
2.4 Activated carbon adsorber
Activated carbon adsorber which used for adsorbing residual chlorine, odor andorganic substances and other harmful substances in raw water, reduce COD content, and to prevent the residual chlorine into RO device, to ensure safety using of membrane element in RO device. This system provided with a diameter of 1200mm vertical active carbon filter, while inside filter filled with activated carbon filter material, and the filter layer height occupy about 600-1200mm of tank. The active carbon adsorber backwashing time based on the blocking degree, which should backwash regularly, to wash away the blockage and broken parts or already reacted particles.
If there are only a certain amount of residual chlorine, but organic matter, smell or color content is minimal; then no need to replace active carbon on adsorber, only supplement wearing or carbon particles in residual chlorine action. If the organic matter content, smell or color is high content in water, generally in 2-3 years the active carbon need to be replaced, and the specific time depends on organic matter and color content, and smell degree in the water.
Because the raw water as tap water, then there will be lots of Ca, Mg plasma, which extremely easy to cause clogging to reverse osmosis membrane, then reduce membrane service life. Our designed anti sludging agent chemical dosing system can react with Ca, Mg plasma in raw water, to prevent such ions into the reverse osmosis device, then to ensure the safe use of RO membrane element.
3. DI water machine Reverse osmosis system
Reverse osmosis system is the key system in manufacturing pure water, while the pre-treatment system is designed to make the reverse osmosis system safe, stable operation. Therefore, the pre-treatment system quality, directly influence the reverse osmosis system quality. So, each system designation whether reasonable or not directly related to investment cost of project, and the economic efficiency of system operation, and service life.
3.1 Security filter (5um)
Before the raw water enter into RO system, in order to prevent the granular impurities in the water into high-pressure pump, and to ensure that the film not damaged, to make sure excellent desalination performance, set the security filter before RO device specially.
This kind of filter can remove particulate which diameter less than 5um. In normal operation, when the filter pressure difference between the inlet and outlet in the value of 0.7kg/cm2, need to replace the filter element, and our filter structure meet the rapid replacement requirements.
3.2 High pressure pump
The purpose of setting up high pressure pump is to make sure reverse osmosis inlet water reaches a certain pressure, then make the reverse osmosis move on, which avoid osmosis pressure making the water molecule through the reverse osmosis membrane to pure water side.
3.3 RO device
Water after security filter through high-pressure pump, then into the RO desalination device. The water into reverse osmosis membrane element in pressure vessel, the inlet water molecules or trace amounts of ions and small molecules will through the membrane into thin barrier to liquid, after via collecting pipe into the middle pure water tank; conversely, can not through film thick water will exhaust out of system by pipe.
The RO device is the core part of project and the desalination. The water by means of reverse osmosis treatment, can eliminate most of inorganic salts,organic matter, microbes.
3.3.1 The selection system device
Membrane components adopt good quality and brand composite membrane, which it’s surface layer as polyamides material, thickness of 2000 angstroms, and supported by a microporous polysulfone layer, which can bear high pressure, and with good resistance to mechanical tension and chemical corrosion. This kind of membrane with features of generate large quantity of water, high desalination rate, with 99% desalination rate to NaCl, CaCl2, and MgCl2.
3.3.2 RO device
Reverse osmosis device arranged on a frame, and with configuration of control system. Water yield standard as under the water temperature 250℃, single membrane element water output can be up to 10500GPD, with desalting rate more than 99%.
Regulating valve is arranged between high pressure pump and reverse osmosis unit, in order to reduce impact high-pressure water flow to the reverse osmosis unit when power-on.
Under low pressure flush, the equipped automatic control solenoid valve discharge unqualified production water when start running. High pressure pipeline system uses stainless steel pipe fitting, low pressure pipeline system using UPVC pipe valve. Reverse osmosis device equipped with spot instrument which display important parameters of pressure drop, operation of equipment, and water desalination rate. The system installed with high, low voltage protection switch, to ensure the safe and reliable operation of RO system.
Each reverse osmosis pressure pipe line membrane water producing side provided with a sample opening, and connected with the sample valve control panel by soft pipe, that is convenient for taking sample.
3.4 Pure water tank
Reverse osmosis water out of outlet, then into pure water tank, equipped with float valve, liquid level meter, liquid level detection is arranged inside the water tank to which can detect liquid level and control pump interlock.