Introduction of main patented equipment for advanced treatment of industrial wastewater
1、 Electrochemical device
The electrocoagulation part of LEM electrochemical device uses the chemical substances produced by metal electrode electrolysis to have a series of complex electrochemical reactions with pollutants in water body, or to be removed by oxidation, or to be dissociated, or to be carried out of water body by secondary gas, or to have reduction reaction, etc., finally realizing the removal of pollutants. Its working principle is that under certain current voltage conditions, on the one hand, the metal anode dissolves Fe2 + and Al3 + plasma and hydrolyzes in water to produce flocculation, on the other hand, a large number of bubbles such as H2 and O2 are produced at the anode and cathode to produce good air flotation effect, and O2 also has oxidation effect on pollutants in water. Through the above series of electrochemical comprehensive action, and then through the subsequent immersion membrane separation method, the flocs adsorbed pollutants were removed, and the water purification was realized.
Compared with the general physical and chemical treatment methods, the advantages of LEM electrochemical device are as follows:
1) The integration of oxidation, adsorption, flocculation, air floatation, solid-liquid separation and other pretreatment means greatly shortens the traditional separation process and saves the space of the system;
2) Using power control means to achieve water pollution control, different voltage and current can be selected according to the pollution content in the water, which has flexible operation and wide application range of water quality;
3) The results show that the hydroxide produced by the electrode has strong flocculation activity and high adsorption efficiency, and the formed floc is large and dense, so it will not re dissolve;
4) It has wide adaptability and tolerance to the pH range and alkalinity of treated water;
5) The equipment has compact structure and high degree of automation;
6) The amount of sludge produced is small and the cost of solid waste treatment is low.
Compared with the traditional electrochemical treatment, the advantages of LEM electrochemical device are as follows
Combined with the characteristics of bipolar type and plug flow type, the backflow phenomenon inside the equipment is strictly eliminated, the current efficiency is increased, and the reactor volume is reduced;
2、 LEM electrochemical device air flotation tank
The air flotation part of LEM electrochemical device adopts the vertical flow inclined plate air flotation tank, which is better than the horizontal flow air flotation tank. The vertical flow inclined plate air flotation tank of our company integrates the sedimentation tank and the air flotation tank. The sludge hopper is set at the bottom to collect the precipitated sludge, and the floating sludge discharge device is set at the upper part to discharge the floating sludge brought by the dissolved air bubbles. It integrates the sedimentation and air flotation functions, and there is no need to set up a separate sedimentation tank, and the waste water is discharged from the tank The bottom diffuses upward, and the hydraulic condition is better than the advection air flotation. Compared with the traditional vertical flow air flotation, the inclined plate design has the advantages of high rising velocity, small equipment diameter, good sedimentation effect, and better effluent quality than the traditional vertical flow air flotation.
Submerged membrane filtration
The immersed PVDF membrane was used to separate the particles in the wastewater, which provided a reliable guarantee for the RO system. The PVDF membrane is placed in the wastewater, and the water is pumped out by the suction pump. The particles are trapped on the surface of the membrane to achieve solid-liquid separation. After a certain period of filtration, the membrane is backwashed and air scrubbed with the filter solution to remove the particles on the surface of the membrane. When the particles in the wastewater reach a certain concentration, part of the wastewater is discharged into the concentration tank, and the solid waste is obtained after plate and frame dehydration The clear liquid returned to the system for further treatment. IMF membrane separation device is used in the system to filter the concentrated water discharged from the circulating water to provide SDI guarantee for the subsequent RO unit.
3、 Advantages of IMF membrane filtration
1) PVDF material with high strength and excellent oxidation resistance is used to ensure its service life. The special sponge structure ensures the filtration precision and high flux. The filtration precision can reach 0.08 um and the water quality is high.
Low flow resistance
High flow resistance
Poor compression tightness and strength
Good compression tightness and strength
Hydrophilic material; pliable
2) IMF membrane filtration core equipment: the membrane module adopts a patent structure specially designed for inorganic filtration system; the middle part is designed with a sludge guide tank, so that the filter cake and impurities can not be accumulated in the module even under high concentration filtration; the operation flux and membrane life are guaranteed; the membrane frame adopts standardized design, which is convenient for installation and maintenance; the membrane structure is designed to ensure the operation flux and membrane life;
IMF membrane framework
Mud guide channel at the bottom of IMF membrane
3) The submerged ultrafiltration system is an open system with wide flow passage and low requirement for pretreatment. It has strong anti pollution and blocking ability for the influent with high suspended solids and organic matter, and also has strong anti impact load ability for the influent with unstable influent quality;
4) The filtration precision of hollow fiber ultrafiltration membrane can reach 0.08 um, and the quality of produced water is high;
5) Submerged ultrafiltration is a kind of direct current total filtration, which operates in a low negative pressure state and pumps water from the outside to the inside to achieve stable operation with low transmembrane pressure difference and moderate membrane flux.
6) IMF has low requirements for pretreatment. Compared with pressure ultrafiltration pretreatment, it needs multi-media filter, self-cleaning filter and other equipment. IMF pretreatment equipment only needs simple solid-liquid separation equipment, with less investment, small land occupation and simple operation and maintenance. Compared with pressure ultrafiltration, it does not need to backwash the pretreatment equipment, replace the filter material and other cumbersome operations.
4、 RO membrane concentration unit
RO membrane has two main functions: one is desalination, the other is concentration. From the process of the whole water treatment system, in order to reduce the operation cost, it is necessary to improve the water recovery rate of RO concentration unit as much as possible to reduce the water quantity of subsequent evaporation unit, so as to achieve the goal of reducing the operation cost.
The advantages of our RO system are as follows:
1) System reflux design avoids concentration polarization and improves recovery;
2) The compound scale inhibitor can effectively prevent the system from scaling at high concentration ratio;
3) Concentrated water detection device, early warning concentrated water crystallization;
4) Special cleaning and detection device for membrane fouling can quickly determine the cleaning scheme;
5) If ro damage is caused by operation during operation, unique on-line membrane repair technology can be provided;
In this project, the RO system adopts the system internal circulation design, so that the water recovery rate reaches 80%.
After a period of operation of reverse osmosis membrane, the organic matter or slightly soluble matter in the feed liquid will cause fouling and plugging of RO membrane module. At this time, chemical cleaning is needed to restore the performance of the membrane. The type of chemical cleaning agent depends on the fouling and plugging substance. The most commonly used is a low pH cleaning solution, which is used to remove inorganic salts. High pH cleaning solution is used to remove oil, biological substances and organic pollutants.
If the pretreatment fails to achieve the expected effect due to operation error or the influent water quality deviates greatly from the design water quality, resulting in serious RO membrane pollution, the conventional cleaning method has no effect. We can provide RO membrane dissection, testing, pollutant analysis, determine the degree of pollution and pollutant composition, so as to provide targeted cleaning scheme.
Our company can provide complete reverse osmosis system, including security filter, high-pressure pump, reverse osmosis components, supporting instruments, valves, piping and body assembly, etc.
5、 ALS accelerated reactor
The working principle of ALS accelerated softener is based on the theory of removing hardness by traditional lime method, that is, adding caustic soda and soda into hard water to precipitate Ca2 + and Mg2 + in the form of CaCO3 and Mg (OH) 2 respectively, so as to soften the water.
The advantages of ALS accelerated softener are that it can contain a large range of calcium hard and total hard, remove SiO2 in water, and effectively prevent the subsequent reverse osmosis fouling.
Compared with the traditional lime softener, the ALS accelerated softener achieves a higher rising velocity through ingenious structural design, which can maintain a higher seed concentration in the reactor, thus accelerating the reaction more effectively and fully, and reducing the equipment volume and floor space. The ALS accelerated softener can remove the hardness and effectively make the crystal grow up on the small concrete surface, which is not only conducive to sedimentation and pressure filtration, but also can completely eliminate the precipitated small particles. The irreversible membrane fouling is caused by blocking the membrane pores, which is the main reason for the failure of other membrane processes. That is to say, as the pretreatment of reverse osmosis, ALS accelerated softener can effectively eliminate some disadvantages of membrane process.
In ALS accelerated softener, the axial-flow circulating pump can fully mix the water body under the unique design of water circulation, and can well control a stream of slag discharge fluid into the sludge tank, so as to effectively control the crystal concentration in the reactor. The supernatant of sludge tank flows back to ALS reactor.
In addition, the ALS system is also equipped with automatic dosing equipment and sludge discharge control equipment. There is an optimal balance value between the water body after crystallization reaction, sludge discharge pump and sludge collection tank, which can keep the particle concentration in the reactor in an optimal reaction state.
Characteristics of ALS accelerated softener:
Destruction of scale inhibitor: in the accelerated softening method, softening agents such as lime are used to absorb and remove the scale inhibitor in the water, which can destroy the effect of the scale inhibitor and lower the calcium concentration in the effluent.
Accelerated reaction: in the design of accelerated softener, maintaining a higher rising flow rate and a higher seed concentration can more effectively accelerate the reaction and particle growth, and reduce the size and occupation of equipment.
Reduce the amount of sludge: the reaction products of accelerated softening are formed on the surface of the original crystal seeds, the final sludge particles are larger and more dense, which is easier to filter, and the amount of sludge is less than that of the traditional lime method.
Improve the system recovery rate: the residual calcium and magnesium in the accelerated softening effluent can reach the theoretical value, such as the subsequent series reverse osmosis system, which can greatly improve the water recovery rate of the whole process.
Application example of ALS accelerated softener:
Shanxi Sunshine Group Huatai Energy Co., Ltd. has two sets of 50m3 / h ALS system.
Ningxia Tianyuan manganese Group Co., Ltd. has two sets of 80 m3 / h and two sets of 100 m3 / h ALS systems.
6、 Aer electro adsorption regeneration device
In this project, aer adsorption regeneration device is used to remove the residual organic matter in wastewater. The filter material adsorption system automatically transfers the filter material to the regeneration tank for electro oxidation regeneration. After regeneration, the filter material is automatically transferred to the adsorption tank for normal operation without manual loading and unloading of filter material. The operation is simple and convenient (see the figure below).
Advantages of aer adsorption regeneration device:
The device is simple, occupies a small area, and has short process;
Low operation cost;
The regeneration cycle can be adjusted according to the change of incoming water quality;
The life of adsorbent is long;
There is no secondary polluted wastewater in regeneration;
Aer is an efficient treatment system for the removal and degradation of organic matter in wastewater; the special conductive adsorption materials in this system enable it to have the functions of adsorption and electrochemical regeneration, so as to remove the organic matter in water economically and effectively, reuse the adsorbent, reduce the operation cost and no secondary pollution discharge.
This system combines adsorption and electro oxidation technology, using conductive particles with high adsorption performance and loading catalyst on them to make them play the role of electro oxidation. Conductive adsorbent can effectively adsorb organic matter in water, and then electro oxidize and regenerate the organic matter adsorbed on the conductive particles by electrochemical method to achieve the function of repeated adsorption The oxidation current completely acts on the organic matter adsorbed on the surface of conductive particles. At this time, the current efficiency is the highest, the reaction is complete and the time is very short. Generally, it can be completely recovered in 30 minutes, and the organic matter in water can be removed economically and effectively
Special regeneration process of organic adsorbent can reduce consumption;
The unique design can utilize waste heat and reduce energy consumption;
Simplify the process and equipment and reduce the total investment;
Optimized equipment design and layout, small footprint;
It is easy to operate and manage;
Multiple devices are connected in parallel to improve the flexibility of operation;