CN214990901U

CN214990901U - Process system for treating precipitated white carbon black wastewater

Info

Publication number: CN214990901U
Application number: CN202021827757.5U
Authority: CN
Inventors: 申志忠; 韩怀见; 陈志勋; 周海; 梁智彪
Original assignee: Jiangxi Blackcat Carbon Black Co ltd
Current assignee: Jiangxi Blackcat Carbon Black Co ltd
Priority date: 2020-08-27
Filing date: 2020-08-27
Publication date: 2021-12-03
Anticipated expiration: 2030-08-27

Abstract

The utility model discloses a process system for treating precipitated white carbon black wastewater, which comprises an electric desiliconization device, an immersed ultrafiltration membrane component, an SRO reverse osmosis system and an evaporation system; the electric desiliconization device is connected with the immersed ultrafiltration membrane component, the immersed ultrafiltration membrane component is connected with the SRO reverse osmosis system, and the SRO reverse osmosis system is connected with the evaporation system. Through experimental verification, the utility model discloses a process systems compares in prior art, can effectively detach the soluble silicon that deposits in the white carbon black waste water, has solved the scale deposit of milipore filter and reverse osmosis membrane better and has blockked up the problem, has prolonged the live time of membrane greatly, has reduced treatment cost, has realized "zero" of depositing the white carbon black waste water and has discharged.

Description

Process system for treating precipitated white carbon black wastewater

Technical Field

The application relates to the technical field of chemical wastewater treatment, and more particularly relates to a process system for treating precipitated white carbon black wastewater.

Background

White carbon black is the common name of synthetic hydrated silica powder, and the name of white carbon black is derived from the fact that white carbon black has the performance similar to that of carbon black for reinforcing rubber. Carbon black has a long history as a reinforcing agent for rubber, and since carbon black has been limited to some applications requiring color as a black reinforcing agent, studies have been made to replace carbon black with chemically synthesized active amorphous silica. Amorphous silica is another excellent reinforcing filler, following carbon black, and is customarily referred to as white carbon, because of its white color.

The white carbon black is mainly divided into precipitated white carbon black and gas-phase white carbon black according to the production method, wherein the precipitated white carbon black is commonly called white smoke, the chemical name of the precipitated white carbon black is precipitated hydrated silicon dioxide, and the molecular formula of the precipitated white carbon black is SiO₂·nH₂O, n, is not constant, and therefore, white carbon black does not have a constant molecular weight. The synthesis process of precipitated silica is essentially the process of converting dense crystalline silica (quartz sand) into loose amorphous hydrated silica, i.e. SiO₂→SiO₂·nH₂And O. The specific process can be mainly divided into the traditional precipitation method and the gel method, wherein the traditional precipitation method is to obtain loose and finely dispersed SiO precipitated in a flocculent structure by acidifying the silicate₂The method has the advantages of easily available raw materials, simple production flow, low energy consumption and low investment. The main raw materials for producing the white carbon black by the traditional precipitation method are liquid water glass and sulfuric acid, and the specific process route is as follows: after the liquid water glass is prepared into a certain concentration, the liquid water glass and sulfuric acid with a certain concentration are respectively sent to a high-level tank, added into a reaction kettle at a certain speed and reacted at a certain temperature. And (3) delivering the reaction finished solution to a curing tank for curing for a certain time, pressurizing by a feeding pump, delivering the solution to a plate-and-frame filter press for separation, cleaning the separated filter cake with clear water, pulping, and delivering the filter cake to a drying tower for drying to obtain the powdery white carbon black product.

In the traditional precipitation method white carbon black production process, two kinds of waste water can appear, the first kind is white carbon black mother liquor (waste water), the mother liquor amount is about 8m³White carbon black, wherein the sodium sulfate containsThe amount was about 5.79%; the second is white carbon black washing water (waste water), the amount of the washing water is about 17m³The white carbon black has a sodium sulfate content of about 0.656%. The total amount of the waste water after mixing the mother liquor and the washing water is 25m³The average content of sodium sulfate in the white carbon black is about 2.559 percent. Meanwhile, the white carbon black mother liquor and the washing wastewater also contain colloidal silica, soluble silicon and other element substances through detection, and the table 1 shows the detection content of part of the element substances in the precipitated white carbon black wastewater.

TABLE 1

Item	Unit of	White carbon black washing water	White carbon black mother liquor
				Cl	mg/L	≥66	≥120
F	mg/L	≥50	≥50
				Ca²⁺	mg/L	≥14	≥17
Mg²⁺	mg/L	≥1.6	≥2.2
				Al³⁺	mg/L	≥0.05	≥0.11
Fe²⁺	mg/L	≥0.05	≥0.09
				Mn	mg/L	≥0.1	≥0.15
Soluble silicon	mg/L	≥200	≥380

The prior art mainly comprises two methods for treating the precipitated white carbon black wastewater. The first method employs direct evaporation, and has the disadvantages of large investment and high operation cost. No matter the production system of 30000 tons of precipitated white carbon black produced in one year adopts multi-effect direct evaporation or MVR direct evaporation, the one-time investment is more than 6000 ten thousand yuan, the cost of each ton of white carbon black is increased by more than 800 yuan, which accounts for about 30% of the production cost, and the production system is unacceptable for production enterprises. The second method adopts membrane separation concentration and evaporation, and because the precipitated white carbon black wastewater contains a certain amount of silicon dioxide, mainly colloidal silicon and soluble silicon, especially because of the existence of the soluble silicon, silica scale can be formed on the membrane after the membrane separation equipment operates for several hours, so that silicon blockage is caused. No matter the ultrafiltration membrane or the reverse osmosis membrane is used, once the silicon plug is formed, the prior art means cannot be cleaned, and only a new membrane can be discarded and replaced, so that a pure membrane separation and concentration mode is fundamentally infeasible. Even if the flocculation precipitation is carried out by adding the chemical silicon removal agent before the membrane separation, the soluble silicon in the wastewater cannot be fully removed, and in addition, the chemical silicon removal agent has high cost, and enterprises cannot bear high operating cost, so far, no production enterprise at home and abroad really realizes the zero discharge of the white carbon black wastewater treatment.

From the above, how to provide a low-cost treatment system for precipitated silica wastewater, so as to achieve zero discharge of precipitated silica wastewater treatment, is a technical problem to be solved urgently at present.

SUMMERY OF THE UTILITY MODEL

Because current sediment white carbon black waste water treatment technique, there is the processing apparatus to require highly, the investment is big, the problem that treatment cost is expensive, can't satisfy manufacturing enterprise's demand to realize sediment white carbon black waste water treatment "zero" and discharge. Therefore, the utility model provides a process system for treating precipitated white carbon black wastewater, which comprises an electric desiliconization device, an immersed ultrafiltration membrane component, an SRO reverse osmosis system and an evaporation system;

the electric desiliconization device is connected with the immersed ultrafiltration membrane component, the immersed ultrafiltration membrane component is connected with the SRO reverse osmosis system, and the SRO reverse osmosis system is connected with the evaporation system.

Preferably, the electric desiliconization device is composed of an electrolytic container and a bracket, wherein the bracket is positioned below the electrolytic container, and two metal electrode plates are arranged in the electrolytic container; the surfaces of the metal electrode plates are mutually parallel and are arranged on two sides in the electrolytic container, and the middle part of the electrolytic container is provided with an electrode plate anode interface and an electrode plate cathode interface which correspond to the metal electrode plates; the electrolytic vessel is characterized in that a water inlet is formed in the middle of the electrolytic vessel, the water inlet is not higher than the lower end of the metal electrode plate, a water outlet is formed in the top end of the electrolytic vessel, and a sewage outlet is formed in the bottom end of the electrolytic vessel.

Preferably, the process system further comprises a sedimentation wastewater tank and a sludge tank;

the sedimentation wastewater tank is connected with the water inlet, the water outlet is connected with the immersed ultrafiltration membrane component, and the sewage discharge outlet is connected with the sludge tank;

the immersed ultrafiltration membrane component is provided with an ultrafiltration treatment water outlet and a sludge outlet, the ultrafiltration treatment water outlet is connected with the SRO reverse osmosis system, and the sludge outlet is connected with the sludge tank.

Preferably, the process system further comprises a clean water tank, the SRO reverse osmosis system is provided with a clean water outlet and a concentrated water outlet, the clean water outlet is connected with the clean water tank, the concentrated water outlet is connected with the evaporation system, the evaporation system is connected with the clean water tank, and the clean water tank is connected with the white carbon black production system and is used for providing water for the white carbon black production system.

Preferably, the sludge tank is connected with a screw stacking machine through a sludge pump, and the screw stacking machine is used for separating dewatered sludge.

Correspondingly, the specific process method of the process system for treating the precipitated white carbon black wastewater comprises the following steps:

carrying out electrolytic desiliconization treatment on the pretreated precipitated white carbon black wastewater by using an electric desiliconization device;

carrying out ultrafiltration treatment on the wastewater subjected to electrolytic desiliconization through an immersed ultrafiltration membrane component to obtain ultrafiltration treated water;

carrying out reverse osmosis treatment on the ultrafiltration treated water through an SRO reverse osmosis system to obtain clear water and concentrated water;

and sending the concentrated water to an evaporation system for evaporation treatment to obtain anhydrous sodium sulfate.

Preferably, the method further comprises:

adding a silicon removing agent, a coagulant aid and a reducing agent into the wastewater after electrolytic silicon removal before the ultrafiltration treatment.

Further, the silicon removing agent is FeCl₃The dosage is 0.01-0.1kg/t water; the coagulant aid is PAM, and the dosage is 0.001-0.005kg/t water; the reducing agent is ammonium bisulfite and is used in amount0.001-0.005kg/t water.

Preferably, the method further comprises:

adding a high silica scale inhibitor to the ultrafiltration treatment water prior to the reverse osmosis treatment.

Further, the high-silicon scale inhibitor is organic phosphate, and the using amount of the high-silicon scale inhibitor is 0.001-0.003kg/t of water.

Preferably, the pretreatment specifically comprises:

cooling precipitated white carbon black wastewater from a workshop wastewater tank by a wastewater cooling tower;

sending the cooled wastewater to a wastewater sedimentation tank for natural sedimentation;

and adding a small amount of alkali into the naturally settled wastewater to neutralize the wastewater to be neutral.

Preferably, the method further comprises:

and (4) conveying flocculate obtained after the ultrafiltration treatment to a sludge tank, and separating dewatered sludge by using a screw stacking machine.

Preferably, the method further comprises:

and sending the evaporation condensed water of the evaporation system and the clean water to a clean water tank for a white carbon black production system to use.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic structural diagram illustrating a process system for treating precipitated silica wastewater in an embodiment of the present invention;

FIG. 2 is a flow chart illustrating a process for treating precipitated silica wastewater according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram illustrating an electrical desiliconization apparatus according to an embodiment of the present invention.

Reference numerals: 1. a water inlet; 2. a water outlet; 3. a sewage draining outlet; 4. an electrode plate anode interface; 5. and an electrode plate cathode interface.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the prior art, pure chemical silicon removal modes such as aluminum salt (PAC flocculant + PAM coagulant aid) and the like are generally adopted for treating white carbon black wastewater, and although the pure chemical silicon removal modes have a certain removal effect on colloidal silicon, the removal efficiency on soluble silicon is extremely low, so that a large amount of soluble silicon enters a subsequent ultrafiltration membrane and a reverse osmosis membrane, and silica scale is formed on the surface of the membrane after hours to pollute the plugging membrane. In the current technology, the best method for cleaning silicon dioxide pollution is to clean with hydrofluoric acid, but the use of hydrofluoric acid cleaning can cause irreparable damage to the film, so once the film forms a silicon plug, the film cannot be cleaned at all in actual operation, only a new film can be replaced, and the cost is too high due to the use of a large amount of chemical silicon removal agents, and enterprises cannot bear high operating cost. Therefore, no matter which treatment method is adopted for precipitated white carbon black wastewater in the prior art, the high operation cost of wastewater treatment is difficult to avoid, so that production enterprises cannot really realize zero discharge of white carbon black wastewater treatment.

In order to solve the technical problem, as shown in fig. 1, a process system for treating precipitated silica wastewater comprises an electric desiliconization device, an immersed ultrafiltration membrane module, an SRO reverse osmosis system and an evaporation system;

Correspondingly, as shown in fig. 2, the specific process method of the process system for treating precipitated silica wastewater includes the following steps:

performing reverse osmosis treatment on the ultrafiltration treated water through an SRO reverse osmosis system to obtain clear water and concentrated water;

Specifically, the utility model discloses a utilize electrolysis chemical flocculation technique to detach the colloidal silica and the soluble silicon (short for electricity desiliconization or electrolysis desiliconization) in the white carbon black waste water of sediment. The electric desiliconization device (see figure 2) is desiliconization equipment which is designed according to the electrochemical electrolysis principle and mainly comprises an electrolytic container and a bracket, wherein the bracket is arranged below the electrolytic container and plays a role in supporting and fixing. Two sides in the electrolytic container are respectively provided with a metal electrode plate which is respectively used as a cathode and an anode, and the middle part of the electrolytic container is provided with an electrode plate anode interface and an electrode plate cathode interface which correspond to the metal electrode plates and are used for supplying power to the metal electrode plates. The middle part of the electrolytic container is provided with a wastewater inlet, the precipitated white carbon black wastewater enters the electric desiliconization equipment for electrolytic desiliconization, and the optimal position of the water inlet is in the same horizontal line or lower than the horizontal line with the lower end of the metal electrode plate, so that the wastewater can be fully subjected to electrolytic desiliconization. The top end of the electrolytic container is provided with a water outlet for discharging the waste water after electrolytic treatment so as to enter the next working procedure. The bottom end of the electrolytic container is provided with a sewage outlet for discharging the flocculated and precipitated pollutants after electrolysis to a sludge tank. The working principle of the electric desiliconization device is as follows: the metal is used as an electrode, the white carbon black wastewater is electrolyzed between the electrode plates, chemical substances generated by the metal electrode during electrolysis and colloidal silicon and soluble silicon in the white carbon black wastewater generate a series of complex electrochemical reactions, or are removed by oxidation, or are separated out by dissociation, or are taken out of a water body by secondary gas, or are subjected to reduction reaction and the like, and finally the removal of the colloidal silicon and the soluble silicon is realized.

In a specific implementation scenario, the specific flow of the electrolytic silicon removal treatment is briefly described as follows: under the condition of certain current and voltage, Fe dissolved out of the metal anode²⁺、Al³⁺(the utility model preferably adopts dissolved Fe²⁺Electrochemical device) plasma is hydrolyzed in water to generate flocculation, and H is generated by the anode and the cathode₂And O₂The air bubbles in the air flow are equal to each other, so that good air floating effect is generated, and O is generated₂The oxidation effect is also realized on colloidal silica, soluble silica and other pollutants to be removed in the white carbon black wastewater. Colloidal silica and soluble silica in the white carbon black wastewater treated by the electrolytic chemical flocculation equipment are changed into flocs such as metal oxides, hydroxides and the like, so that the flocs are removed by a precipitation mode.

In order to remove the flocculates such as metal oxides and hydroxides formed in the electrolytic desiliconization treatment more conveniently and effectively, in the preferred embodiment of the present invention, a desiliconization agent, a coagulant aid and a reducing agent are added to the wastewater after the electrolytic desiliconization treatment and before the ultrafiltration treatment.

Specifically, flocs such as metal oxides and hydroxides formed by electrolytic desiliconization are matched with a small amount of desiliconization agent, coagulant aid and reducing agent (or other auxiliary agents with the same action), so that the specific surface area of the particles of the flocs is increased, the activity is improved, the stability is good, and the precipitation effect is improvedThe fruit is better. Preferably, the silicon removing agent is FeCl₃The dosage is 0.01-0.1kg/t water; the coagulant aid is PAM (polyacrylamide), and the dosage is 0.001-0.005kg/t water; the reducing agent is ammonium bisulfite, and the dosage is 0.001-0.005kg/t water. The addition amounts of the silicon removing agent, the coagulant aid and the reducing agent are far lower than the addition amount of the traditional chemical agent for removing silicon, so that the cost is reduced, and the secondary pollution is avoided. It should be noted that the dosage unit of the chemical reagent of the present invention is calculated based on the amount of wastewater actually treated.

At present, in the white carbon black industry, pure chemical agents are adopted to remove silicon in the research process of white carbon black precipitation wastewater treatment, and the white carbon black precipitation wastewater treatment is realized by improving membrane separation equipment. And the utility model discloses broken present sediment white carbon black waste water treatment's thinking and limited, utilize electricity to remove the silicon mode or electricity to remove the method that silicon + chemical agent combined together, remove silicon and chemistry through the electricity and remove silicon, membrane separation and evaporation mutual synergism, not only reduce treatment cost by a wide margin, still realized the pioneer of sediment white carbon black waste water treatment "zero" emission.

In order to improve the effect of electrolytic desiliconization, in the preferred embodiment of the present invention, before electrolytic desiliconization, the precipitated silica wastewater needs to be pretreated, and the pretreatment specifically is:

Specifically, white carbon black wastewater containing sodium sulfate produced in the white carbon black production process by a precipitation method enters a workshop wastewater tank, the temperature of the wastewater is usually about 70 ℃, the wastewater is sent to a wastewater cooling tower for cooling treatment by a hot water pump, the wastewater enters a precipitation wastewater tank for natural precipitation after the temperature of the wastewater is reduced to below 40 ℃, and the wastewater after the impurities and part of precipitates are removed by precipitation is sent to an electric desiliconization device by the wastewater pump. Because the pH value of the wastewater is about 4.5 and is not suitable for electrolysis, a small amount of alkali needs to be added to neutralize the wastewater to be neutral before the wastewater enters the electric desiliconization device, and the electrolyzed metal hydroxide makes the wastewater tend to be alkalescent in the flocculation process, which is more beneficial to flocculation and precipitation of the wastewater.

The utility model discloses utilize submergence formula milipore filter subassembly to separate flocculation thing and salt solution, obtain ultrafiltration treatment water. After the white carbon black wastewater is subjected to electric desiliconization, flocculation and precipitation, the rest suspended matters containing silicide are remained, and then most of silicide in the water can be removed through a subsequent immersed ultrafiltration membrane component. The immersed ultrafiltration membrane component is membrane separation equipment adopting an immersed ultrafiltration membrane (preferably a patent product CN206828149U), can be directly immersed in a water tank, and can be flushed by air disturbance, so that the ultrafiltration membrane can still stably run when the concentration of suspended matters in the white carbon black wastewater reaches 1-2%. Meanwhile, the immersed ultrafiltration component adopts a unique slotted design, so that the suspended matters containing silicide which are left after the electric desiliconization flocculation precipitation can be quickly separated from the membrane component and can not be accumulated in the ultrafiltration membrane, the influence of the adhesion on the surface of the membrane on the filtration effect is avoided, and the flux of the membrane is ensured. Therefore, the immersed ultrafiltration membrane component has stronger impact resistance to the water quality fluctuation of the white carbon black wastewater, can not be blocked after long-time operation, and also overcomes the problem of incomplete flocculation reaction of the traditional ultrafiltration membrane because the retention time of suspended matters in the membrane pool is prolonged. And the immersed ultrafiltration membrane component and the electric desiliconization device are cooperatively used and applied to the treatment of the precipitated white carbon black wastewater, so that the soluble silicon in the wastewater is greatly removed, and the subsequent treatment method of reverse osmosis and evaporation is ensured to be smoothly carried out.

In order to fully recover and treat the white carbon black wastewater, in the preferred embodiment of the utility model, flocculate obtained after the ultrafiltration treatment is sent to a sludge tank, and dewatered sludge is separated by a screw stacking machine. Specifically, after silicon in the wastewater passing through the electric desiliconization device is flocculated by adding agents such as a desiliconization agent, a coagulant aid and the like, the wastewater enters an immersed ultrafiltration membrane assembly to separate flocculate from saline water, the separated flocculate (sludge) is discharged into a sludge tank, the sludge is pumped to a screw stacking machine by a sludge pump to be dewatered, and dewatered sludge with low water content is separated out and is pulled by a truck for subsequent treatment. It should be noted that the sludge tank contains not only flocs obtained after the ultrafiltration treatment but also contaminants discharged from the electric desiliconization apparatus and precipitated contaminants generated in other processes.

And the salt water that is the ultrafiltration processing water after the ultrafiltration processing is pressurized by the high pressure pump and then enters the SRO reverse osmosis system for salt concentration, in order to make the SRO reverse osmosis membrane operate stably, in the preferred embodiment of the utility model, before the reverse osmosis processing, the high-silicon scale inhibitor is added into the ultrafiltration processing water. The high-silica scale inhibitor is optimized according to the characteristics of silica scale, preferably, the high-silica scale inhibitor is organic phosphate, the using amount of the high-silica scale inhibitor is 0.001-0.003kg/t of water, the high-silica scale inhibitor has high dispersibility, enhances the dispersion effect on soluble silicon, and is used for controlling scale formation and deposits in a reverse osmosis membrane separation system and reducing particle blockage.

The salt content of the concentrated water concentrated by the reverse osmosis system is about 12 percent, and the concentrated water is pumped to an evaporation system for evaporation treatment to obtain the industrial I class anhydrous sodium sulfate with more than first-class quality. The evaporation system can adopt multi-effect evaporation or MVR evaporation system. And sending the evaporation condensed water of the evaporation system and the 'clear water' concentrated by the reverse osmosis system to a clear water tank for a white carbon black production system to use. It should be noted that, in the present invention, "concentrated water" refers to wastewater with high salt content generated in the reverse osmosis desalination process, and "clear water" refers to desalted water generated in the reverse osmosis desalination process.

For further describing the scheme of this application, it is verified that the process system for treating precipitated silica wastewater provided by the present invention is tested in combination with the specific embodiments.

Example 1

Cooling precipitated white carbon black wastewater from a workshop wastewater tank through a wastewater cooling tower, sending the cooled wastewater to a precipitated wastewater tank for natural sedimentation, and neutralizing a small amount of alkali in the naturally sedimentated wastewater to be neutral and then carrying out electrolytic desiliconization through an electric desiliconization device. After electrolytic desiliconization, a small amount of desiliconization agent, coagulant aid and reducing agent are added, ultrafiltration treatment is carried out by an immersed ultrafiltration membrane component, and after a high-silicon scale inhibitor is added into ultrafiltration treatment water, reverse osmosis treatment is carried out by an SRO reverse osmosis system, so that clear water and concentrated water are obtained. Sending the concentrated water to an evaporation system for evaporation treatment to obtain anhydrous sodium sulfate. And sending the evaporation condensed water of the evaporation system and the clean water to a clean water tank for the white carbon black production system to use. Wherein the amounts of the respective chemicals are shown in table 2.

TABLE 2

Example 2

Cooling precipitated white carbon black wastewater from a workshop wastewater tank through a wastewater cooling tower, sending the cooled wastewater to a precipitated wastewater tank for natural sedimentation, adding a large amount of desiliconization agent, coagulant aid and reducing agent for chemical desiliconization, carrying out ultrafiltration treatment through an immersed ultrafiltration membrane component after chemical desiliconization, adding a high-silicon scale inhibitor into ultrafiltration treatment water, and then carrying out reverse osmosis treatment through an SRO reverse osmosis system to obtain 'clear water' and 'concentrated water'. Sending the concentrated water to an evaporation system for evaporation treatment to obtain anhydrous sodium sulfate. And sending the evaporation condensed water of the evaporation system and the clean water to a clean water tank for the white carbon black production system to use. Wherein the amounts of the respective chemicals are shown in Table 3

TABLE 3

Embodiment 1 is the utility model provides a adopt electrolysis to remove silicon technology and handle the process method of precipitation white carbon black waste water, embodiment 2 is the difference with embodiment 1 adopts the traditional chemistry among the prior art to remove silicon technology before carrying out ultrafiltration treatment. Table 4 compares the silicon content data of the water before entering the reverse osmosis system for example 1 and example 2; table 5 shows the operating data for the reverse osmosis system of example 2; table 6 shows the operating data of the reverse osmosis system of example 1.

TABLE 4

TABLE 5

TABLE 6

As can be seen from Table 4, the conventional chemical silicon removal technology can only remove the silicon content in the silica white wastewater from 330mg/L to about 80mg/L, and although the service life of the membrane can be prolonged, the silicon blockage of the membrane can still be caused after the membrane is operated for a long time. As shown in Table 5, the flow rates of the clear water and the concentrated water in the operation process of the reverse osmosis membrane are reduced along with the time after the silicon is removed by adopting the traditional chemical agent, and the pressure difference between the inlet and the outlet of the reverse osmosis membrane is increased. This indicates that the reverse osmosis membrane becomes more clogged over time, and in fact after 97 hours of operation of the system, the reverse osmosis system is forced to shut down because of the clogging.

This is because the conventional chemical silicon removal technology has the following disadvantages:

1. the traditional chemical flocculation forms a flocculating agent with small specific surface area, low activity and more bound water, so the stability is poor and the separation is not facilitated; 2. in the traditional chemical flocculation, flocculates are suspended in liquid in the flocculation process, so that the removal of suspended matters is not facilitated; 3. traditional chemical flocculation cannot effectively remove tiny colloidal substances.

And the traditional chemical desiliconization treatment of precipitated silica wastewater has high cost and complex process. In the prior art, the oxidation, adsorption, flocculation, solid-liquid separation and other measures are generally carried out step by step, and the treatment process and the device are complicated and easily generate some uncontrollable adverse factors; a large amount of chemical agents are added in the chemical flocculation, secondary pollution is caused, and meanwhile, a process of neutralizing or removing anions is needed in the subsequent process, so that the process is complex; the total soluble solid content in the effluent of the chemical flocculation is higher, so that the water recovery cost is increased; the cost of the specific chemical agent is about 4.01 yuan/ton of wastewater, and the service life of the membrane is short and the membrane needs to be replaced frequently.

And the utilization of the electrolytic desiliconization technology of the utility model can economically remove the soluble silicon content which is difficult to remove in the white carbon black wastewater from 330mg/L to below 30 mg/L. Practice proves that the silicon content of the ultrafiltration membrane and the reverse osmosis membrane is below 30mg/L and silicon blockage is not generated. And the water after silicon removal enters a relatively mature membrane separation concentration and evaporation system, so that the zero discharge of the purification treatment of the white carbon black wastewater can be realized. As shown in the table 6, adopt the utility model discloses the flow of reverse osmosis membrane operation in-process "clear water" and "dense water" all has not obvious change along with going on of time after the electrolysis desiliconization, and reverse osmosis membrane's exit differential pressure also does not have the change moreover, and reverse osmosis system still can normally go on after 384 hours of continuous operation in fact, and can not produce stifled membrane phenomenon. The utility model discloses the electricity that adopts removes the silicon method can reach the purpose that precipitation method white carbon black waste water removed silicon (mainly refer to soluble silicon) through power consumption and a small amount of electrode, and the running cost is lower relatively, and electricity that electricity removed silicon and electrode expense be 1.4 yuan/ton waste water, and the cost of increase is within the acceptable within range of enterprise. Meanwhile, the service life of the membrane is longer, so that the treatment cost of the precipitated white carbon black wastewater is greatly reduced.

And compared with the prior art, the utility model, still have following advantage:

1. the flocculating constituent formed in the flocculation process of the utility model has large specific surface area, high activity and less bound water, thus having higher stability and easy separation and greatly shortening the settling time; 2. the total soluble solid content in the effluent after the flocculation by the technology of the utility model is lower, which can greatly reduce the water recovery cost; 3. the utility model has strong destabilization effect on the polluted colloid due to the electrolyzed metal hydroxide, so the utility model is very effective in removing the tiny colloid substances, which can greatly reduce the danger of the blockage of the subsequent reverse osmosis system membrane; 4. the utility model has the advantages that a large amount of chemical agents are not needed to be added, so that the secondary pollution is avoided, and the electrolyzed metal hydroxide can lead the waste water to tend to be alkalescent in the flocculation process, which is more beneficial to flocculation and sedimentation, so that a small amount of alkali is only needed to be added in the earlier stage to neutralize to be neutral, and the alkali consumption is reduced; 5. the utility model can generate tiny bubbles in the flocculation process, and can carry flocculate to float to the surface of the liquid, so that the flocculate can be removed more easily; 6. the utility model discloses multiple means such as oxidation, absorption, flocculation, air supporting, solid-liquid separation are integrated to the technique for process flow shortens greatly, and processing apparatus is simple easy to operate, has also significantly reduced the device space simultaneously.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not necessarily depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.

Claims

1. A process system for treating precipitated white carbon black wastewater is characterized by comprising an electric desiliconization device, an immersed ultrafiltration membrane component, an SRO reverse osmosis system and an evaporation system;

2. The process system of claim 1, wherein:

the electric desiliconization device is composed of an electrolytic container and a bracket, wherein the bracket is positioned below the electrolytic container, and two metal electrode plates are arranged in the electrolytic container; the surfaces of the metal electrode plates are mutually parallel and are arranged on two sides in the electrolytic container, and the middle part of the electrolytic container is provided with an electrode plate anode interface and an electrode plate cathode interface which correspond to the metal electrode plates; the electrolytic vessel is characterized in that a water inlet is formed in the middle of the electrolytic vessel, the water inlet is not higher than the lower end of the metal electrode plate, a water outlet is formed in the top end of the electrolytic vessel, and a sewage outlet is formed in the bottom end of the electrolytic vessel.

3. The process system of claim 2, further comprising a sedimentation lagoon and a sludge lagoon;

4. The process system of claim 2, further comprising a clean water tank, wherein the SRO reverse osmosis system is provided with a clean water outlet and a concentrated water outlet, the clean water outlet is connected to the clean water tank, the concentrated water outlet is connected to the evaporation system, the evaporation system is connected to the clean water tank, and the clean water tank is connected to the white carbon black production system for providing water for the white carbon black production system.

5. The process system of claim 3, wherein the sludge tank is connected to a screw stack machine for separating dewatered sludge by a sludge pump.