CN111606449B

CN111606449B - Treatment process of ultraviolet absorbent production wastewater

Info

Publication number: CN111606449B
Application number: CN202010415862.6A
Authority: CN
Inventors: 陆舒飞; 潘行平
Original assignee: Fujian Desheng Technology Co ltd
Current assignee: Fujian Desheng Technology Co ltd
Priority date: 2020-05-16
Filing date: 2020-05-16
Publication date: 2022-11-01
Anticipated expiration: 2040-05-16
Also published as: CN111606449A

Abstract

The invention discloses a treatment process of ultraviolet absorbent production wastewater, and relates to the technical field of wastewater treatment. The process comprises the following steps: step one, neutralizing: adjusting the pH value of the wastewater mixture to 8-9, and carrying out solid-liquid separation treatment; step two, primary precision filtration: carrying out primary precision filtration after solid-liquid separation treatment; step three, first resin adsorption: carrying out deaminizing treatment by adopting macroporous adsorption resin; step four, secondary fine filtration: adjusting the pH value of the wastewater subjected to deamination treatment to 3-4, and performing secondary fine filtration; step five, carrying out resin adsorption for the second time: and (4) dephenolizing the wastewater subjected to secondary fine filtration by adopting macroporous adsorption resin to obtain treated water. Through the treatment process, impurities such as phenol organic matters, aniline organic matters, suspended matters and the like in the wastewater mixture are effectively removed, the efficiency of wastewater treatment is improved, and the content of the treated medium-macromolecule organic pollutants reaches the water inlet requirement of electrodialysis or MVR.

Description

Treatment process of ultraviolet absorbent production wastewater

Technical Field

The invention relates to the technical field of wastewater treatment, in particular to a treatment process of wastewater generated in ultraviolet absorbent production.

Background

The ultraviolet absorbent is the most widely used light stabilizer at present, and can be classified into salicylate ultraviolet absorbent, benzophenone ultraviolet absorbent, benzotriazole ultraviolet absorbent, substituted acrylonitrile ultraviolet absorbent, triazine ultraviolet absorbent and the like according to the structure. The most industrially used are benzophenone-type ultraviolet absorbers and benzotriazole-type ultraviolet absorbers. The two ultraviolet absorbers have strong absorption capacity and can effectively absorb ultraviolet light with the wavelength of 270-380nm, wherein, the benzotriazole ultraviolet absorbers have the advantages of oil resistance, discoloration resistance, low volatility, low toxicity and good compatibility with polymers, and are widely applied to synthetic materials and products, such as polyvinyl chloride, polystyrene, unsaturated resin, polycarbonate, polymethyl methacrylate, polyethylene, ABS resin, epoxy resin, cellulose resin and the like; it is also suitable for the fields of photosensitive material, such as colour film, colour photographic paper and high-molecular polymer, etc., in particular for colourless, transparent and light-coloured products.

At present, a phenol organic substance and an aniline organic substance are generally adopted as main synthetic raw materials at home and abroad, and the benzotriazole ultraviolet absorbent is prepared by processes such as diazo coupling and the like under the conditions of strong acid and strong alkali. However, the wastewater after preparing the benzotriazole ultraviolet absorbent contains phenols, aniline organic matters and a large amount of inorganic salts, the COD of the wastewater is up to tens of thousands and the total nitrogen is up to thousands. At present, the treatment methods generally adopted for the wastewater are mainly chemical methods and biochemical methods.

The chemical redox method has a plurality of means, including Fenton method, iron-carbon micro-electrolysis method, electrooxidation method, wet oxidation method and supercritical method; the biochemical principle is mainly to culture special bacteria to adapt to the high-salinity and high-toxicity wastewater environment and decompose the organic matters in the wastewater environment.

At present, there are also some processes for treating wastewater with ultraviolet absorbers. Specific examples are as follows:

the method for recovering polyaluminium chloride from aluminum trichloride wastewater by using synthetic triazine ultraviolet absorbent disclosed in Chinese patent application with application publication No. CN106673040A and application date of 2016, 12 and 19 discloses a wastewater treatment step:

(1) Adding aluminum scraps into the aluminum trichloride wastewater, stirring, heating to 85-90 ℃, and preserving heat to obtain a liquid with a pH value of 3.5-4.5;

(2) Cooling the liquid obtained in the step (1) to 20-50 ℃, adding activated carbon, stirring, filtering, and removing unreacted aluminum scraps, insoluble impurities and organic impurities adsorbed by the activated carbon to obtain a filtrate;

(3) And (3) putting the filtrate obtained in the step (2) into a container, stirring and heating the filtrate to 100-105 ℃ for refluxing, filling the reflux liquid into a water separator, continuously refluxing until chlorobenzene or o-dichlorobenzene does not sink, collecting the lower-layer solvent, discharging water in the water separator, continuously distilling the water, and detecting that the density of the residual liquid is more than or equal to 1.10g/ml at 20 ℃, thus obtaining the liquid polyaluminium chloride.

The aluminum trichloride wastewater for synthesizing the triazine ultraviolet absorbent is treated by adopting the treatment mode in the patent application, although a flocculation effect can be formed while no new waste is generated, so that the purification treatment of the wastewater is improved, the treatment mode has pertinence, and if impurities in the wastewater are generated when the synthetic ultraviolet absorbent UV-P, UV-531, the treatment effect is not ideal.

In addition, in the project example of UV-P factory wastewater treatment project with ultraviolet absorbent [ Zhou Lin, huang Junyi, 2017 (6), 112-115], after the wastewater is neutralized, the wastewater is treated by adopting the modes of iron-carbon micro-electrolysis, fenton oxidation, hydrolytic acidification, AO + biological filter and ozone strong oxidation. However, this treatment method is required to have a high treatment efficiency due to microelectrolysis of iron and carbon, and thus it is difficult to perform a wide range of treatments, or the treatment method tends to increase the treatment cost. In addition, the operation of the biological filter is added, and special bacteria are cultured to adapt to a high-salinity and high-toxicity wastewater environment, so that the culture of the special bacteria has high treatment space and treatment cost, the treatment effect fluctuates greatly along with the inflow water, and the treatment time is long.

For the treatment of wastewater generated by preparing the ultraviolet absorbent UV-531, the conventional treatment method of a common enterprise is to perform evaporation treatment and then burn the evaporated residue. However, this treatment method is likely to result in high treatment cost and secondary pollution. There are also processes for treating the wastewater by using microwave radiation in enterprises, however, the operation requirement of microwave treatment is high and the operation difficulty is high, and the process is difficult to be widely popularized.

In addition, a mode of adopting complexation extraction pretreatment to prepare wastewater generated by ultraviolet absorbent UV-531 [ Yang Zhilin, wang Kaichun, zhang Binbin and the like, industrial water and wastewater, 2012,43 (2), 17-21] is adopted, in the mode, HLE complexation extraction technology is adopted to treat the wastewater generated by preparing ultraviolet absorbent UV-531, the extracting agents are trioctyl phosphine oxide and N, N-bis- (1-methylheptyl) acetamide as complexing agents, kerosene is adopted as a diluting agent, and chemical treatment is adopted, so that other substances are added, other impurities are easily generated in the wastewater, secondary pollution is easily generated, the difficulty in wastewater treatment is improved, and secondary pollution is easily generated.

Chinese patent applications with application publication numbers of CN108117217A and application publication date of 2018, 06 and 05 disclose an optimized treatment process for BTA/TTA high-salt wastewater, which comprises the following steps:

(1) Delivering BTA/TTA high-salinity wastewater into a preceding-stage raw wastewater tank through a filter, and sequentially and continuously feeding wastewater into a resin adsorption tower through an adsorption circulating pump by wastewater entering the preceding-stage raw wastewater tank, wherein the flow is controlled to be 200-300 mL/h; the waste water entering the resin adsorption tower is continuously adsorbed by two stages through a resin column in the adsorption tower, and aniline in the waste water is adsorbed on the waste water;

(2) After resin adsorption, the pretreated wastewater passes through a wastewater pump at a flow rate of 1-3 m³The flow rate of the solution per hour is sent into an evaporator, evaporation crystallization is carried out at the temperature of 75-85 ℃, and finally solid-liquid separation is carried out on evaporation crystallization concentrated solution to obtain treated clear solution;

(3) After each 100L of wastewater is treated, the resin column in the resin adsorption tower needs to be subjected to regeneration treatment, and the regeneration treatment comprises the following specific steps:

step 1: after the resin adsorption tower is emptied, the prepared 3-5% sodium hydroxide solution is continuously sent to the resin column to be activated by an alkaline liquor pump, and the flow is required to be controlled to be 1-3 m³H, cleaning the resin column, wherein the cleaning amount is controlled to be 1-1.5m³；

Step 2: conveying desorption liquid obtained after the cleaning solution passes through the resin column to a layering tank, conveying waste water containing phenol obtained after layering to the resin adsorption tower in the step (2) for continuous treatment, recovering phenol obtained after layering, and completely blowing out alkaline water in the resin column by using compressed air after the alkaline water cleaning is finished;

and step 3: and (3) conveying the dilute sulfuric acid solution in the dilute acid tank to the resin column through a circulating pump, repeatedly circulating, acidifying residual alkali liquor, stopping running, simultaneously activating the resin, returning the sulfuric acid solution to the acid tank for reuse, and blowing the activated resin with air for later use.

And after the BTA/TTA high-salinity wastewater is filtered by a filter, resin adsorption is carried out, and aniline in the wastewater is adsorbed onto the resin. However, in this process, the aniline organic substance is easily oxidized, and once oxidized, the aniline organic substance easily blocks the resin, resulting in a decrease in resin adsorption efficiency. And if the organic matter in the wastewater is of a large variety, the difficulty of wastewater treatment is increased.

Therefore, the treatment method for treating the wastewater which is obtained by preparing the ultraviolet absorbent and contains a large amount of phenols, aniline organic matters and inorganic salts, has COD (chemical oxygen demand) of more than tens of thousands and total nitrogen of thousands, has short treatment time and high treatment efficiency, and has great significance and wide market application prospect.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a process for treating wastewater generated in ultraviolet absorber production, which mainly adopts a physical method for treatment and has higher treatment efficiency on wastewater containing phenolic organic matters and amine organic matters.

In order to achieve the purpose, the invention provides the following technical scheme:

a treatment process of ultraviolet absorbent production wastewater comprises the following steps:

step one, neutralizing: adjusting the pH value of the wastewater mixture to 8-9, and performing solid-liquid separation treatment to obtain wastewater;

step two, primary precision filtration: carrying out primary precision filtration on the wastewater subjected to solid-liquid separation treatment;

step three, first resin adsorption: performing deamination treatment on the wastewater subjected to the primary precision filtration by using macroporous adsorption resin;

step four, secondary fine filtration: adjusting the pH value of the wastewater subjected to deamination treatment to 3-4, and performing secondary fine filtration;

step five, carrying out resin adsorption for the second time: carrying out dephenolization treatment on the wastewater subjected to secondary precision filtration by adopting macroporous adsorption resin to obtain treated water;

the waste water mixture is formed by mixing acidic waste water and alkaline waste water, the waste water mixture contains waste acid and waste alkali, the waste acid is one of hydrochloric acid and sulfuric acid, and the waste alkali is liquid alkali.

By adopting the technical scheme, in the first step, the wastewater mixture is the mixture of acidic wastewater and alkaline wastewater, the wastewater and the wastewater with different acid-base degrees are mixed with each other, the wastewater mixture contains waste acid and waste alkali, the waste acid is one of hydrochloric acid and sulfuric acid, the waste alkali is liquid alkali, and the waste alkali and the liquid alkali are mixed, so that the required pH value range can be reached, and the two types of wastewater can be treated simultaneously. The wastewater mixture obtained in the application contains a large amount of phenol organic matters, aniline organic matters, metal ions and the like. The pH value of the wastewater mixture is adjusted to precipitate zinc ions in the wastewater mixture, and then solid-liquid separation is carried out (generally, filter pressing operation can be carried out by adopting equipment such as a filter press) to fully remove solid impurities in the wastewater mixture.

Through test detection, the COD of the wastewater obtained through the treatment of the first step is about 20000-30000mg/L, the content of phenol organic matters is about 3000-4000mg/L, and the content of aniline organic matters is about 2000-3000mg/L.

In the present application, the pH adjuster used for adjusting the pH is usually sulfuric acid, hydrochloric acid, sodium hydroxide, or the like. In the first step and the fourth step, the pH value of the wastewater is respectively adjusted, so that the operation is adopted, aniline organic matters and phenol organic matters in the wastewater can be respectively adsorbed and removed by the macroporous adsorption resin in the second step and the fourth step in the process of performing amine removal treatment and phenol removal treatment on the wastewater through the change of the pH value (in the second step, the macroporous adsorption resin can adsorb a small amount of phenol organic matters while adsorbing the aniline organic matters), so that the aniline organic matters and the phenol organic matters in the wastewater are effectively removed, and the purpose of purifying the wastewater is achieved. Meanwhile, the efficiency of wastewater treatment can be improved by adopting the operation method.

In addition, in the application, the pH value is adjusted to be 8-9 in the first step, the first fine filtration is carried out in the pH value range in the second step, and the first resin adsorption is carried out in the third step, so that aniline substances can be removed; then the pH value is adjusted and reduced to be within the range of 3-4, and then secondary fine filtration and secondary resin adsorption are carried out, thereby being beneficial to removing the phenols in the solution.

The present invention in a preferred example may be further configured to: and extracting with water after the treatment in the step five to obtain sodium chloride or sodium sulfate.

By adopting the technical scheme, the operation mode is hazardous waste recovery treatment, and the sodium chloride or sodium sulfate meeting the industrial standard after recovery can be used in the electrolysis industry, so that the pollution to the environment is reduced, and the full utilization of chemicals can be improved.

The present invention in a preferred example may be further configured to: the macroporous adsorption resin subjected to the first resin adsorption in the third step and the second resin adsorption in the fifth step needs to be subjected to the following recovery operations:

s1, washing macroporous adsorption resin with water;

s2, cleaning the macroporous adsorption resin with a regeneration solution to obtain a desorption solution and regenerated macroporous adsorption resin;

s3, washing the regenerated macroporous adsorption resin with water;

the regeneration liquid in the step S2 is any one of toluene, petroleum ether, n-octane, chloroform or methanol water solution and ethanol water solution with the mass percentage concentration of 50-99%.

By adopting the technical scheme, the high-salinity wastewater can be replaced by adopting water washing in the step S1. In step S2, after the macroporous adsorbent resin is washed with any one of toluene, petroleum ether, n-octane, chloroform, and a 50-99% methanol aqueous solution or ethanol aqueous solution, the regenerated solution is a mixed solution containing methanol, water, phenol, or aniline, which is also called a desorption solution (regenerated solution after treatment). The desorption liquid can be converted into regeneration liquid again after rectification treatment, and the macroporous adsorption resin can be cleaned. Therefore, the regeneration liquid can be recycled, and the cost is saved.

The regenerated liquid is also good for organic solvents such as toluene, petroleum ether, n-octane and chloroform which do not corrode or dissolve the macroporous adsorption resin, and is also good for alcohol substances such as methanol aqueous solution and ethanol aqueous solution, so that the phenol organic substances and aniline organic substances in the macroporous adsorption resin can be dissolved sufficiently, but the performance of the macroporous adsorption resin is not easily influenced.

The regenerated solution may be an acidic aqueous solution or an alkaline aqueous solution instead of the above solvent, however, when an acidic aqueous solution or an alkaline aqueous solution is used, the amount of acidic or alkaline waste water is easily increased, and the difficulty and cost of waste water treatment are increased. Therefore, compared with the prior art, the methanol aqueous solution is more favorable for saving cost, has higher efficiency of wastewater treatment, and is not easy to cause additional wastewater amount.

The macroporous adsorption resin cleaned by the regeneration liquid is cleaned by water, which is beneficial to absorbing methanol out.

And (4) rectifying the residual methanol in the macroporous adsorption resin treated in the step (S3) to fully remove the residual methanol, so that the adsorption capacity of the macroporous adsorption resin is recovered.

The present invention in a preferred example may be further configured to: and rectifying and extracting the desorption solution obtained in the step S2 to obtain phenol substances and aniline substances.

Through adopting above-mentioned technical scheme, can carry out recycle to desorption liquid, extract and recycle phenol type material and aniline type material wherein, be favorable to reducing the pollution to the environment and reduce the degree of difficulty of water treatment, can also improve the make full use of degree of chemicals, in addition, still be favorable to bringing extra profit for the mill. And the comprehensive consideration is favorable for reducing the final cost of treatment.

1. When the regeneration liquid is a methanol aqueous solution:

1. and (4) collecting the regenerated liquid, and separating by a heating mode of a rectifying tower according to the difference of the boiling point of the regenerated liquid and water.

2. Adding the regenerated liquid from the middle part of the rectifying tower, adopting corrugated packing and controlling the temperature, and recovering and obtaining a high-purity volatile organic solvent at the tower top; the tower bottom can recover and obtain components with high purity and difficult volatilization, which comprise phenol, aniline and water.

3. The product obtained from the tower top is used as regeneration liquid to be reused in the resin desorption process; and after the product obtained at the bottom of the tower is further dried, phenol and aniline organic matters are left and can be used as process raw materials for production, so that the full recycling of the raw materials is facilitated, the economic benefit is improved, and the pollution to the environment is reduced.

2. When the regeneration liquid is toluene:

1. and (4) collecting the regenerated liquid, and separating the regenerated liquid in a layered mode through a reaction kettle according to the difference of the density of the regenerated liquid and water.

2. After the regeneration liquid is put into a reaction kettle, toluene, phenol and aniline organic matters can be obtained on the upper layer through full stirring and standing layering; the lower layer can obtain water with higher density.

3. The upper layer low-density organic phase can be used as a process raw material after rectification treatment and reused in the production process; the lower layer high-density water sample returns to the sewage pool.

The present invention in a preferred example may be further configured to: the macroporous adsorption resin adopted in the third step and the fifth step comprises at least one of polystyrene divinylbenzene macroporous adsorption resin and neutral adsorption resin containing lipid group.

By adopting the technical scheme, before the third step and the fifth step, the pH value of the wastewater is adjusted, and the polystyrene divinylbenzene macroporous adsorption resin and the neutral adsorption resin containing the lipid group can adsorb organic matters in the wastewater within the corresponding pH value range, so that a better purification treatment effect is achieved.

The macroporous adsorbent resin used in the present application may be any one of LS-100, LS-106, LS-200, and LS-206 (produced by Shaanxi blue deep Special resins Co., ltd.), or any one of XDA-1, XDA-200, XDA-300, and XDA-11 (produced by Xian blue Xiao science and technology New materials Co., ltd.), but is not limited to the macroporous adsorbent resins of the corresponding types produced by the above two companies.

The present invention in a preferred example may be further configured to: and (4) performing first resin adsorption in the third step and second resin adsorption in the fifth step, wherein the volume flow rate of the wastewater passing through the macroporous adsorption resin is 1-5 times of the volume/hour of the macroporous adsorption resin.

By adopting the technical scheme, the volume flow rate of water flow passing through the macroporous adsorption resin is not too high, otherwise, the phenomenon that the adsorption effect of the macroporous adsorption resin on organic matters in wastewater is not good enough easily occurs, and the phenomenon of low treatment efficiency is easily caused. After the macroporous adsorption resin treatment in the mode and the step three treatment, the removal rate of the aniline in the effluent reaches more than 99.5 percent; after the treatment of the fifth step, the removal rate of the phenols in the effluent is more than 99.5 percent.

The present invention in a preferred example may be further configured to: in the second fine filtration, activated carbon is added into the wastewater after the solid-liquid separation treatment, and the volume of the activated carbon accounts for 0.04-0.5% of the volume of the wastewater after the solid-liquid separation treatment; and step four, secondary fine filtration, namely adding activated carbon into the wastewater after dephenolization treatment, wherein the volume of the activated carbon accounts for 0.04-0.5% of the volume of the wastewater after dephenolization treatment.

Through adopting above-mentioned technical scheme, after the solid-liquid separation of step one handles, the great impurity of volume or organic matter are got rid of, but still have the impurity of more small volume in the remaining waste water, through adding active carbon in step two to carry out physical adsorption to the little volume impurity in the waste water, through first microfiltration, can realize tentatively getting rid of the purpose of the tiny particle impurity wherein.

After the third step, a large amount of aniline organic matters are removed, tar and suspended small-volume impurities in the wastewater are removed by adding activated carbon in a similar manner, and even part of aniline organic matters are removed, so that the wastewater is further purified on the basis of the second step, and the adsorption efficiency of the second resin in the fifth step is higher.

In addition, the volume of adding of active carbon has great floating space, mainly is relevant with the impurity of waste water and the cost of handling, if the volume of active carbon addition is too big, is difficult for causing great change to the promotion of the effect of adsorbing impurity, nevertheless can cause the improvement of treatment cost.

The invention in a preferred example may be further configured to: the first fine filtration and the second fine filtration are both carried out by adopting filter pieces with the aperture of 2-20 mu m; the filtering piece is any one of a cloth bag, a microporous filter, a sintered plate, a ceramic membrane and PP cotton.

By adopting the technical scheme, because the activated carbon adsorbs impurities with small volume, the volume is enlarged, and when the activated carbon is filtered by a filter screen with the aperture of 18-20 mu m, the activated carbon can be better cleaned and the impurities adsorbed on the surface of the activated carbon can be better removed. The cloth bag, the microporous filter, the sintered plate, the ceramic membrane and the PP cotton have better chemical stability, are not easy to react with acid and alkali substances, are corrosion-resistant, have high strength, are not easy to absorb water, can be repeatedly utilized after being cleaned, and are favorable for saving the treatment cost.

And in the process of filtering by the filter piece with the aperture of 2-20 mu m, water flow is easy to flow out of the aperture, so that the problem of too long filtering treatment time is avoided.

More preferably, in the step S1 and the step S3, the volume of water used for washing is 2 to 3 times of the volume of the macroporous adsorption resin, and the water flow rate during washing is 1 to 2 times of the volume/hour of the macroporous adsorption resin.

By adopting the technical scheme, in the step S1 and the step S3, the macroporous adsorption resin is cleaned by clear water, the water consumption and the water flow speed are moderate, the high-salinity wastewater in the macroporous adsorption resin can be fully replaced by the operation of the step S1, and the methanol in the macroporous adsorption resin can be fully replaced by the operation of the step S3.

The invention in a preferred example may be further configured to: in the step S2, when the regeneration liquid is adopted for cleaning, the use amount of the regeneration liquid is 2-3 times of the volume of the macroporous adsorption resin; the flow rate of the regeneration liquid is 1-5 times of the volume/hour of the macroporous adsorption resin.

By adopting the technical scheme and the process parameters, the regeneration liquid is helpful for fully cleaning the macroporous adsorption resin, so that organic matters adsorbed on the macroporous adsorption resin can be fully removed, the macroporous adsorption resin is recycled, and the removal efficiency of phenol organic matters and aniline organic matters during recycling of the macroporous adsorption resin is not easily influenced.

In conclusion, the invention has the following beneficial effects:

firstly, the wastewater to be treated mainly contains phenol organic matters and aniline organic matters, the operation processes of neutralization, first fine filtration, first resin adsorption, second fine filtration and second resin adsorption are adopted, before the first resin adsorption and the second resin adsorption are carried out, the pH value of the wastewater is respectively adjusted, impurities such as phenol organic matters, aniline organic matters and suspended matters with larger sizes in a wastewater mixture are effectively removed, the wastewater treatment efficiency is improved, the content of the treated medium-macromolecule organic pollutants meets the water inlet requirement of electrodialysis or MVR, and the subsequent operation is facilitated.

Secondly, the physical method is mainly adopted to purify the phenol organic matters and the aniline organic matters, the treatment time is short, the process is mild, other reaction byproducts are not easy to appear, and the convenience of water treatment is increased.

Thirdly, after the macroporous adsorbent resin for treating wastewater is used, the phenol organic matters and the aniline organic matters adsorbed on the macroporous adsorbent resin are removed through the cleaning treatment of the regeneration liquid, so that the macroporous adsorbent resin recovers the adsorption capacity, can be recycled, does not cause secondary pollution, and is favorable for saving the treatment cost of wastewater.

Fourthly, the regeneration liquid is changed into desorption liquid containing water, methanol, concentrated phenols and aniline organic matters after cleaning the macroporous adsorption resin, the desorption liquid can be subjected to low-energy-consumption rectification separation subsequently, and materials separated subsequently are recycled, i.e. the phenols and amines are recycled, so that the cost is saved. Through tests and calculations by the applicant: the macroporous adsorbent resin can be used for 200 times (1 m) at a frequency of once a day and 150 times a year according to the service life of 3 years³The resin can be treated by 30m at a time³200 times of water for treating 6000m³The cost is obviously saved due to the waste water.

Fifthly, the adsorption process adopts a one-use one-standby process, namely two standby towers run in parallel, when the towers are saturated in adsorption, the two parallel standby towers are converted into the adsorption towers to run in parallel, and meanwhile, the adsorption saturation towers are converted into desorption regeneration. Because the first resin adsorption and the second resin adsorption adopt different pH values, the macroporous adsorption resin adopts the same type of desorbent, and the content of the aniline organic matter is less than that of the phenol organic matter, the 'integrated desorption' is adopted, namely desorption liquid firstly flows through an aniline adsorption tower and then is introduced into the phenol organic matter adsorption tower through a pump to carry out secondary desorption, the use efficiency of regeneration liquid such as methanol aqueous solution and the like is increased, and the use amount is reduced. This also explains why the macroporous adsorbent resin used in the first resin adsorption in step three and the second resin adsorption in step five is subjected to the recovery operation in this order.

Detailed Description

The present invention will be described in further detail with reference to examples.

Example 1: a treatment process of ultraviolet absorbent production wastewater comprises the following steps:

step one, neutralizing: blending acid wastewater containing sulfuric acid and alkaline wastewater containing sodium hydroxide to form a wastewater mixture, and adjusting the pH value to 8, wherein the composition of the wastewater mixture is shown in Table 1; performing filter pressing by a filter press, and performing solid-liquid separation treatment to obtain wastewater;

step two, primary precision filtration: adding activated carbon into the wastewater after the solid-liquid separation treatment, wherein the volume of the activated carbon accounts for 0.04 percent of the volume of the wastewater after the solid-liquid separation treatment; carrying out primary precision filtration on the wastewater subjected to solid-liquid separation treatment by adopting PP cotton with the aperture of 18 mu m;

step three, first resin adsorption: performing deamination treatment on the wastewater subjected to the primary precision filtration by adopting macroporous adsorption resin, wherein the volume flow rate of the wastewater passing through the macroporous adsorption resin is 1 time of the volume/hour of the macroporous adsorption resin;

step four, secondary fine filtration: adding activated carbon into the wastewater after dephenolization treatment, wherein the activated carbon accounts for 0.04% of the wastewater after dephenolization treatment; adjusting the pH value of the wastewater subjected to deamination treatment to 3, and performing secondary precision filtration by using PP cotton with the aperture of 18 mu m as a filter element;

step five, carrying out resin adsorption for the second time: and (3) dephenolizing the wastewater subjected to the secondary fine filtration by using macroporous adsorption resin, wherein the volume flow rate of the wastewater passing through the macroporous adsorption resin is 1 time of the volume/hour of the macroporous adsorption resin, and the treatment is completed.

Table 1 specific composition of the waste water mixture of example 1

Wherein the model of the macroporous adsorption resin adopted in the first resin adsorption and the second resin adsorption is LS-100. The o-phenylenediamine can be replaced by other aniline substances; the o-amino-p-cresol can be replaced by other phenols, and the structural formulas of the two types of the phenol are respectively shown as follows:

in the structural formula, the substituents R, R and R3 are respectively any one of halogen elements, hydroxyl, carboxyl and alkyl.

Example 2: a process for treating wastewater from ultraviolet absorbent production, which is different from the process of example 1, is characterized in that in the first step of preparation, the pH value of the wastewater mixture is adjusted to 9, and then filter pressing is carried out by a filter press;

in the second step, the addition of the active carbon is 0.05 percent, and the wastewater after the solid-liquid separation treatment is subjected to primary fine filtration by adopting a sintered plate with the aperture of 20 mu m;

in the third step, the volume flow rate of the wastewater passing through the macroporous adsorption resin is 5 times of the volume/hour of the macroporous adsorption resin;

in the fourth step, the adding amount of the active carbon is 0.05 percent, the pH value of the wastewater after the deamination treatment is adjusted to 4, and PP cotton with the aperture of 20 mu m is adopted for secondary fine filtration;

in the fifth step, the volume flow rate of the wastewater passing through the macroporous adsorption resin is 5 times of the volume/hour of the macroporous adsorption resin.

Wherein the model of the macroporous adsorption resin adopted in the first resin adsorption and the second resin adsorption is LS-106.

Example 3: a process for treating wastewater from ultraviolet absorber production, which is different from example 1, is that the composition of wastewater mixture is shown in Table 2. And blending the two kinds of wastewater, and neutralizing until the pH value is 8 to form a wastewater mixture.

Table 2 specific composition of the waste water mixture of example 3

Wherein the model of macroporous adsorption resin adopted in the first resin adsorption and the second resin adsorption is XDA-1; the o-phenylenediamine can be replaced by other aniline substances; the o-amino-p-cresol can be replaced by other phenols, and the structural formulas of the two types of the phenol are respectively shown as follows:

Example 4: the difference between the process for treating the wastewater generated in the production of the ultraviolet absorbent and the example 1 is that after the treatment in the second step and the treatment in the fifth step, two kinds of macroporous adsorption resins are respectively subjected to recovery treatment:

s1, washing the macroporous adsorption resin with water, wherein the water consumption is 2 times of the volume of the macroporous adsorption resin, the water flow speed is 1 time of the volume/hour of the macroporous adsorption resin, and the washing time is 2 hours.

S2, cleaning the macroporous adsorption resin by adopting an ethanol water solution with the mass percentage concentration of 99%, wherein the using amount of steam is 2 times of the volume of the macroporous adsorption resin; the flow rate of the steam is 1 time of the volume/hour of the macroporous absorption resin, and the time of the steam cleaning is 2 hours.

And S3, washing the macroporous adsorption resin with water, wherein the water consumption is 2 times of the volume of the macroporous adsorption resin, the water flow speed is 1 time of the volume/hour of the macroporous adsorption resin, and the washing time is 2 hours.

And S4, rectifying the treated regenerated liquid.

Wherein the model of macroporous adsorption resin adopted by the first resin adsorption is LS-206; the model of macroporous adsorption resin adopted in the second resin adsorption is XDA-200.

Example 5: a process for treating wastewater from ultraviolet absorbent production, which is different from that in example 2, comprises the step S1 of washing macroporous adsorbent resin with water in an amount of 2 times the volume of the macroporous adsorbent resin and at a water flow rate of 1.2 times the volume/hour of the macroporous adsorbent resin when the macroporous adsorbent resin is recycled.

S2, cleaning the macroporous adsorption resin by adopting a methanol aqueous solution with the mass percentage concentration of 50%, wherein the using amount of the methanol aqueous solution is 3 times of the volume of the macroporous adsorption resin; the flow rate of the methanol aqueous solution is 3 times of the volume/hour of the macroporous adsorption resin, and the cleaning time of the methanol aqueous solution is 1h.

And S3, washing the macroporous adsorption resin with water, wherein the using amount of the water is 2 times of the volume of the macroporous adsorption resin, and the water flow speed is 1.2 times of the volume/hour of the macroporous adsorption resin.

Wherein the model of macroporous adsorption resin adopted by the first resin adsorption is XDA-11; the model of the macroporous adsorption resin adopted in the second resin adsorption is LS-200.

Example 6: a treatment process of ultraviolet absorber production wastewater is different from that in example 3 in that when macroporous adsorption resin is subjected to recovery treatment, S1, the macroporous adsorption resin is washed with water, the water consumption is 3 times of the volume of the macroporous adsorption resin, the water flow speed is 2 times of the volume of the macroporous adsorption resin per hour, and the washing time is 1.5 hours.

S2, cleaning the macroporous adsorption resin by adopting a methanol aqueous solution with the mass percentage concentration of 99%, wherein the using amount of the methanol aqueous solution is 2 times of the volume of the macroporous adsorption resin; the flow rate of the methanol aqueous solution is 5 times of the volume/hour of the macroporous adsorption resin, and the cleaning time of the methanol aqueous solution is 0.4h.

And S3, washing the macroporous adsorption resin with water, wherein the water consumption is 3 times of the volume of the macroporous adsorption resin, the water flow speed is 2 times of the volume/hour of the macroporous adsorption resin, and the washing time is 1.5h.

Wherein the type of macroporous adsorption resin adopted for the first resin adsorption is XDA-300; the model of macroporous adsorption resin adopted in the second resin adsorption is XDA-200.

Comparative example

Comparative example 1: a process for treating wastewater from ultraviolet absorber production, which is different from example 1 in that the operations of step two and step four are not used.

Comparative example 2: a process for treating wastewater from ultraviolet absorber production, which is different from that of example 1 in that the operation of step two is not used.

Comparative example 3: a process for treating wastewater from ultraviolet absorber production, which is different from example 1 in that the operation of step four is not used.

Comparative example 4: the difference between the process for treating the wastewater generated in the production of the ultraviolet absorbent and the example 1 is that the treatment steps are as follows:

step one, blending acid wastewater containing sulfuric acid and alkaline wastewater containing sodium hydroxide to form a wastewater mixture, and adjusting the pH value to 8, wherein the composition of the wastewater mixture is shown in table 1; then filter pressing is carried out by a filter press, solid-liquid separation treatment is carried out, and wastewater is obtained;

adding active carbon into the wastewater, wherein the active carbon accounts for 0.04% of the wastewater, adjusting the pH value of the wastewater to 3, and performing precision filtration I by using PP cotton with the pore diameter of 18 mu m as a filter element;

step three, dephenolizing the wastewater subjected to the precision filtration I by adopting macroporous adsorption resin, wherein the volume flow rate of the wastewater passing through the macroporous adsorption resin is 1 time of the volume/hour of the macroporous adsorption resin;

step four, adding activated carbon into the wastewater again, wherein the activated carbon accounts for 0.04 percent of the wastewater; adjusting the pH value of the wastewater subjected to solid-liquid separation to 8, and performing precision filtration II by using PP cotton with the aperture of 18 mu m;

and step five, performing deamination treatment on the wastewater subjected to the precision filtration II by using macroporous adsorption resin, wherein the volume flow rate of the wastewater passing through the macroporous adsorption resin is 1 time of the volume/hour of the macroporous adsorption resin, and finishing the treatment.

Comparative example 5: a process for treating wastewater from ultraviolet absorber production, which is different from the process of example 1 in that the pH value in the first step is adjusted to 7.5; the pH in step four was adjusted to 2.5.

Test one: purification detection test

The test method comprises the following steps: the wastewater obtained after each step in example 1 was subjected to index analysis, which included: color, COD, pH value, content of phenols and aniline. The wastewater after each step in examples 2 to 3 and comparative examples 1 to 3 was examined and analyzed in the same manner.

And (3) test results: the indexes of wastewater after the respective steps in example 1 are shown in table 3; the indexes of wastewater after the steps in example 2 are shown in table 4; the wastewater indexes after the respective steps in example 3 are shown in table 5. Indexes of wastewater after each step in comparative example 1 are shown in table 6; indexes of wastewater after each step in comparative example 2 are shown in table 7; indexes of wastewater after each step in comparative example 3 are shown in table 8; indexes of wastewater after each step in comparative example 4 are shown in table 9; indexes of wastewater after each step in comparative example 5 are shown in table 10.

TABLE 3 index of wastewater after each step in example 1

TABLE 4 wastewater index after each step in example 2

TABLE 5 wastewater index after each step in example 3

TABLE 6 index of wastewater after each step in comparative example 1

TABLE 7 index of wastewater after each step in comparative example 2

TABLE 8 index of wastewater after each step in comparative example 3

TABLE 9 index of wastewater after each step in comparative example 4

TABLE 10 index of wastewater after each step in comparative example 5

As shown in tables 3-10, examples 1-3 have a relatively high treatment effect on wastewater mixtures, no matter the color, COD, pH value, or the content of phenol organic matters and aniline organic matters, and can meet the water inlet requirement of electrodialysis or MVR after the second resin adsorption.

In comparative examples 1 to 3, however, the indexes of the finally obtained wastewater were not satisfactory because the treatments in step two and step four were omitted to various degrees. In comparative example 4, the phenol type organic matter was removed first, and then the aniline type organic matter was removed, and after the first resin adsorption, the wastewater was still pale red and turbid. At this time, the phenol organic matter is oxidized under acidic conditions, and even after the first resin adsorption treatment, the phenol organic matter cannot be sufficiently removed, and the residual amount is large, which indicates that the resin is easily clogged in the first resin adsorption process, and the removal efficiency of the phenol organic matter by the resin is greatly affected. Although the oxidized phenol organic matters can be removed to a certain extent through the fine filtration II and the treatment of the macroporous adsorption resin again, the phenol organic matters are still more remained in the water treated in all the steps compared with the content in the examples 1 to 3, so that the phenol organic matters are difficult to adsorb by the adsorption resin in the last time, and the efficiency of wastewater treatment is finally reduced. In comparative example 5, the content of phenol organic matters and the content of aniline organic matters in the treated wastewater are respectively higher than those in the wastewater treated in examples 1 to 4, and the results show that in the operation process, whether the pH value is adjusted reasonably or not is easy to influence the treatment effectiveness of the wastewater.

And (2) test II: regeneration test of macroporous adsorbent resin

1. The macroporous adsorbent resins (first used) obtained after the recovery treatments in examples 4 to 6 were used as test samples 4 to 6. The test samples 4 to 6 were applied to the wastewater treatment in examples 1 to 3, respectively, and the indexes of the wastewater obtained after each step in examples 1 to 3 were tested and recorded.

2. After the above-mentioned mode is adopted to repeatedly recover and reuse for 200 times, the treated macroporous adsorption resin is respectively applied to the above-mentioned examples 1-3 to treat waste water, and the indexes of the waste water obtained after each step of the above-mentioned examples 1-3 are tested and recorded.

And (3) test results: the wastewater treatment capacities of the test samples 4 to 6 after 200 times of washing are shown in tables 11 to 13.

TABLE 11 ability of test sample 4 to treat wastewater after 200 washes

TABLE 12 ability of test sample 5 to treat wastewater after 200 washes

TABLE 13 ability to treat wastewater of test sample 6 after 200 washes

As can be seen from tables 11 to 13 and tables 2 to 4, the test samples 4 to 6 can maintain good purification effect on wastewater after being used for the first time and being cleaned for 200 times and recycled, can effectively remove phenol organic matters and aniline organic matters in the wastewater, and also has significant effect of reducing COD in the wastewater. The method for cleaning the macroporous adsorption resin can remove phenol organic matters and aniline organic matters adsorbed in the macroporous adsorption resin, so that the macroporous adsorption resin can keep good impurity adsorption and wastewater purification capabilities. And the macroporous adsorption resin still has excellent purification capacity after 200 times of cleaning, which shows that the treatment mode in the embodiments 4-6 in the application is not easy to damage the macroporous adsorption resin and is beneficial to prolonging the service life of the macroporous adsorption resin.

And (3) test III: test of extraction ratio of corresponding substances in water and desorption solution after treatment

Test samples: selecting the treated water obtained by the process in the embodiment 1-3 as a test sample 1-3; selecting desorption liquid obtained by processing the macroporous adsorption resin subjected to the first resin adsorption in the third step of the embodiment 1-3 in the step S2 as a test sample 1'-3'; the desorption solution obtained by subjecting the macroporous adsorbent resin subjected to the second resin adsorption in the fifth step of examples 1 to 3 to the treatment in the step S2 was selected as a test sample 1"-3".

The test method comprises the following steps: the test samples 1 to 3 were heated, and the solid substance finally obtained was sodium chloride or sodium sulfate. Rectifying the test sample 1'-3', and recording the extraction rate of phenol and aniline organic matters in the test sample; rectifying the test sample 1'-3', recording the extraction rate of phenol and aniline organic matters in the test sample, and analyzing the recorded extraction rate.

And (3) test results: the solids obtained by extraction from test samples 1 to 3 and the extraction rates thereof are shown in Table 14; the extraction rates of the phenol and aniline organic compounds obtained in test samples 1'-3' and 1'-3' are shown in Table 15.

TABLE 14 solids extracted from test samples 1-3 and their extraction rates

Test specimen	The obtained solid	Extraction ratio of solids/%)
			Test sample 1	Sodium sulfate	4.62
Test sample 2	Sodium sulfate	4.62
			Test sample 3	Sodium chloride	5.56

TABLE 15 extraction rates of phenol type organic substance and aniline type organic substance obtained in test samples 1' -3' and 1' -3

As can be seen from table 14, after the water obtained after the wastewater treatment process in the present application is treated, the water is removed, so that the sodium sulfate or sodium chloride can be fully extracted, and then the sodium sulfate or sodium chloride is recycled, which is beneficial to bringing extra income to enterprises.

As can be seen from table 15, the adsorbent resin obtained by the first resin adsorption (deamidation) and the adsorbent resin obtained by the second resin adsorption (dephenolation) were washed with the respective regeneration liquids, and the contents of the residual phenol organic substances and aniline organic substances in the desorption liquids obtained were 5%. After rectification treatment is carried out on desorption liquid obtained by cleaning the adsorption resin after the first resin adsorption, aniline organic matters and phenol organic matters which can be recovered respectively account for about 80 percent and about 20 percent, which shows that the proportion of the aniline organic matters attached to the macroporous adsorption resin after the deamination treatment is far higher than the content of the phenol organic matters, and the aniline organic matters and the phenol organic matters can be fully rectified and obtained; after the desorption solution obtained by cleaning the adsorption resin adsorbed by the second resin is rectified, aniline organic matters and phenol organic matters which can be recovered respectively account for about 20 percent and about 80 percent, which shows that the ratio of the phenol organic matters attached to the macroporous adsorption resin after the dephenolization treatment is far higher than the content of the aniline organic matters, and the aniline organic matters and the phenol organic matters can be fully rectified and obtained. The phenol organic matter and the aniline organic matter obtained by rectification can be recycled.

The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.

Claims

1. A treatment process of benzotriazole ultraviolet absorbent production wastewater is characterized by comprising the following steps:

step one, neutralizing: mixing acidic wastewater obtained by producing benzotriazole ultraviolet absorbent with alkaline wastewater, adjusting the pH value to 8-9, and carrying out solid-liquid separation treatment to obtain wastewater;

in the first step, each ton of the acidic wastewater contains 1.6kg of o-phenylenediamine sulfate, 1.8kg of o-amino-p-cresol sulfate, 57.7kg of zinc sulfate, 182.0kg of sodium bisulfate and 8978 kg of water zxft 8978 kg; 38.9kg of sulfuric acid; each ton of the alkaline wastewater contains 8.1kg of o-phenylenediamine and 3.3kg of o-amino-p-cresol, wherein the weight percentages of the o-phenylenediamine, the o-amino-p-cresol, the sodium metaaluminate, the water and the sodium hydroxide are respectively 122.4kg, 814.2kg and 52kg;

or

Each ton of the acidic wastewater contains 2.2kg of zinc chloride, 30.2kg of hydrochloric acid, 0.4kg of toluene, 2.2kg of UV328 and 965kg of water; each ton of the alkaline waste water contains 7.7kg of o-phenylenediamine, 3.3kg of o-aminodipentylphenol, 122.3kg of sodium metaaluminate and 866.7kg of water;

in the second fine filtration, activated carbon is added into the wastewater after the solid-liquid separation treatment, and the volume of the activated carbon accounts for 0.04-0.5% of the volume of the wastewater after the solid-liquid separation treatment;

the macroporous adsorption resin adopted in the third step and the fifth step comprises at least one of polystyrene divinylbenzene macroporous adsorption resin and neutral adsorption resin containing lipid group;

the first resin adsorption in the third step and the second resin adsorption in the fifth step, wherein the volume flow rate of the wastewater passing through the macroporous adsorption resin is 1-5 times of the volume/hour of the macroporous adsorption resin;

the second fine filtration in the fourth step is to add activated carbon into the dephenolized wastewater, wherein the volume of the activated carbon accounts for 0.04-0.5% of the volume of the dephenolized wastewater;

and extracting with water after the treatment in the step five to obtain sodium chloride or sodium sulfate.

2. The process for treating benzotriazole UV absorbent production wastewater according to claim 1, wherein the macroporous adsorbent resin subjected to the first resin adsorption of step three and the second resin adsorption of step five is subjected to the following recovery operations:

s1, washing macroporous adsorption resin with water;

s3, washing the regenerated macroporous adsorption resin with water;

3. The process for treating benzotriazole ultraviolet absorber production wastewater according to claim 2, wherein the desorption solution obtained in step S2 is rectified and extracted to obtain phenols and anilines.

4. The process for treating benzotriazole ultraviolet absorber production wastewater according to claim 2, wherein in step S2, when cleaning is performed by using a regeneration liquid, the usage amount of the regeneration liquid is 2-3 times of the volume of the macroporous adsorption resin; the flow rate of the regeneration liquid is 1-5 times of the volume/hour of the macroporous adsorption resin.