Method for irradiation treatment of aromatic protein compounds in coking wastewater

Abstract

The application provides a method for irradiation treatment of aromatic protein compounds in coking wastewater, and belongs to the field of wastewater treatment, and aims to solve the problems of poor treatment effect of common flocculants on aromatic protein compounds and high cost; the method comprises the following steps: step 1, a mixture of iron sulfate and ferrous sulfate is added to biochemical effluent of coking wastewater, and the biochemical effluent is subjected to irradiation treatment to obtain pretreated liquid; wherein the mass ratio of the iron sulfate to the ferrous sulfate is 0.1-1:1; step 2, polyacrylamide is added to the pretreated liquid, and after standing and precipitation, the obtained supernatant is used as treated effluent; wherein the addition amount of the polyacrylamide is 0.1-2 mg / L.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage treatment, in particular to a method for irradiation treatment of aromatic protein compounds in coking wastewater. BACKGROUND

[0002] Coking wastewater is a typical refractory industrial wastewater with the characteristics of complex pollutant composition, high concentration of organic pollutants and high ammonia nitrogen. At present, the process of ammonia evaporation + air flotation + biochemical treatment + advanced treatment is usually used to treat coking wastewater. Among them, the biochemical treatment effluent contains refractory macromolecular organic pollutants represented by aromatic protein compounds, so that the COD of the biochemical treatment effluent is between 150-300 mg / L, which is much higher than the effluent concentration specified in the National "Coke Chemical Industry Pollutant Discharge Standard". Therefore, the removal of aromatic protein compounds by the advanced treatment unit plays an important role in ensuring that the treated effluent meets the discharge standard.

[0003] The commonly used advanced treatment technologies include high-level oxidation technology, electron beam degradation technology, membrane technology and coagulation treatment technology, etc. The high-level oxidation technology includes ozone oxidation, Fenton oxidation, etc., which mainly uses the active species such as hydroxyl radicals generated in the system to oxidize organic pollutants; but the selectivity of hydroxyl radicals for oxidation of pollutants is poor, and a large amount of inorganic substances in wastewater will compete with organic pollutants for active species, reducing the utilization efficiency of active species, resulting in large consumption of oxidizing agent and high cost. The electron beam degradation technology is to degrade organic pollutants in water through the direct action of high-energy electron beam and the indirect action of active particles generated by high-energy electron beam; compared with high-level oxidation technology, electron beam degradation technology has the characteristics of high treatment efficiency and no need to add chemicals, but at present, the removal of organic pollutants by electron beam mainly utilizes the degradation effect of active species generated by electron beam, which needs a very high irradiation dose to further oxidize the degradation intermediates of macromolecular aromatic protein compounds, so as to effectively mineralize them. Compared with the above two technologies, the membrane technology mainly removes organic pollutants by separation, which has the advantages of simple operation and good treatment effect, but a large amount of concentrated liquid is produced, and membrane pollution and membrane blockage are easy to occur during operation. The coagulation method can aggregate macromolecular organic pollutants in wastewater by using coagulant to form flocculation body, so as to separate them from wastewater, which has the advantages of good treatment effect, simple operation, mild reaction conditions, etc., and has been widely used in the advanced treatment of coking wastewater.

[0004] However, the treatment effect of the coagulation method for treating wastewater is affected by factors such as the existence form of organic pollutants and the type of coagulant; colloidal organic pollutants are easy to aggregate into flocculation bodies under the action of coagulant and settle; and dissolved organic pollutants need to increase the dosage of coagulant or use high molecular coagulant to be adsorbed on the flocculation body to be removed. Among them, the aromatic protein compounds in the biochemical effluent of coking wastewater exist in colloidal state and dissolved state, and the coexistence of colloidal and dissolved organic pollutants in such water quality leads to poor coagulation treatment effect and large coagulant dosage. Therefore, it is necessary to develop a method for removing aromatic protein compounds in coking wastewater with high efficiency and low cost in the coagulation process. SUMMARY

[0005] Therefore, the present application aims to provide a method for irradiation treatment of aromatic protein compounds in coking wastewater to solve the problem of poor coagulation effect of aromatic protein compounds, resulting in large coagulant dosage and high cost.

[0006] In a first aspect, the present application provides a method for irradiation treatment of aromatic protein compounds in coking wastewater, comprising:

[0007] Step 1: adding a mixture of ferric sulfate and ferrous sulfate to the biochemical effluent of coking wastewater, and irradiating the biochemical effluent to obtain a pretreated liquid; wherein the mass ratio of the ferric sulfate to the ferrous sulfate is 0.1-1:1;

[0008] Step 2: adding polyacrylamide to the pretreated liquid, and after standing and precipitating, taking the obtained supernatant as the treated effluent; wherein the dosage of the polyacrylamide is 0.1-2 mg / L.

[0009] Further, the ratio of the dosage of the ferric sulfate to the COD of the coking wastewater is 1-3:1.

[0010] Further, the irradiation dose of the irradiation treatment is 1-5 kGy.

[0011] Further, the polyacrylamide is an anionic polyacrylamide, and the dosage of the polyacrylamide is 0.1-0.5 mg / L.

[0012] Further, the standing and precipitating time is 1-5 min.

[0013] Further, the irradiation treatment is electron beam irradiation, and the electron beam irradiation is performed by an electron accelerator.

[0014] Further, the ratio of the dosage of the ferric sulfate to the COD of the coking wastewater is 1:1.

[0015] Further, the irradiation dose of the irradiation treatment is 1 kGy.

[0016] Further, the adding amount of the polyacrylamide is 0.1 mg / L.

[0017] Further, the mass ratio of the ferrous sulfate and the ferric sulfate is 1:1.

[0018] The method for removing aromatic protein compounds in coking wastewater by irradiation treatment provided by the application has the following advantages over the prior art:

[0019] The method for removing aromatic protein compounds in coking wastewater by irradiation treatment provided by the application comprises the following steps: in step 1, a mixture of ferric sulfate and ferrous sulfate is added to the biochemical effluent of coking wastewater, and the biochemical effluent is subjected to irradiation treatment to obtain a pretreated liquid; wherein the mass ratio of the ferric sulfate and the ferrous sulfate is 0.1-1:1; in step 2, polyacrylamide is added to the pretreated liquid, and after standing and precipitation, the obtained supernatant is used as treated effluent; wherein the adding amount of the polyacrylamide is 0.1-2 mg / L.

[0020] Thus, in the method for removing aromatic protein compounds in coking wastewater by irradiation treatment provided by the application, the mixture of ferric sulfate and ferrous sulfate is added to the biochemical effluent of coking wastewater, and subjected to irradiation treatment, so that, under the action of the oxidizing active species generated by iron ions and ferrous ions during irradiation, Fe Then, it further reacts with ferrous ions in the solution to form Fe 2+ x Fe 3+ y (OH) 2x+3y The substance can promote the aggregation of colloidal organic matter through surface electric neutralization, adhesion bridging, net trapping and other mechanisms, and can also promote the adsorption of aromatic protein compounds on the coagulant by complexing with the amino groups in the aromatic protein compounds through the empty orbit of iron atoms, thereby improving the adsorption removal effect. In addition, under a relatively low irradiation dose, the active species generated by electron beam irradiation can initiate a chain reaction of free radicals in water, so that the aromatic protein compounds are converted into free radicals containing aromatic rings, which are easy to polymerize into colloidal macromolecular organic matter, thereby promoting the mutual aggregation of the colloidal macromolecular organic matter and the coagulant into flocculating bodies. At the same time, the addition of polyacrylamide to the wastewater after irradiation treatment can further promote the flocculating bodies to become large alum flowers and rapidly settle, so that the aromatic protein compounds have a good removal effect. Moreover, the use of ferrous sulfate and ferric sulfate in combination with electron beam irradiation achieves the effect of coagulation, and the dosage of the coagulant is less than that of the single addition of the coagulant, and the generated Fe 2+ x Fe 3+ y (OH) 2x+3yThe aromatic protein compound can be removed by adsorption, the required amount of polyacrylamide is less, and the cost is lower. BRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the application and are incorporated herein in conjunction with the description of the application. The drawings are as follows:

[0022] Figure 1 A flow chart showing the steps of the method for irradiation treatment of aromatic protein compounds in coking wastewater according to the embodiment of the application is shown in Fig. 1.

[0023] Figure 2 Three-dimensional fluorescence spectra of the biochemical effluent of coking wastewater before and after treatment according to Example 1 are shown in Figs. 2A and 2B, respectively. Figure 2 Fig. 2A shows the three-dimensional fluorescence spectrum of the biochemical effluent of coking wastewater before treatment according to Example 1. Figure 2 Fig. 2B shows the three-dimensional fluorescence spectrum of the biochemical effluent of coking wastewater after treatment according to Example 1.

[0024] Figure 3 Fig. 3 shows the three-dimensional fluorescence spectrum of the biochemical effluent of coking wastewater after treatment according to Example 2.

[0025] Figure 4 Fig. 4 shows the three-dimensional fluorescence spectrum of the biochemical effluent of coking wastewater after treatment according to Example 3. DETAILED DESCRIPTION

[0026] In order to make the above objectives, features and advantages of the present application more apparent, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments of the present application will be described in detail below, and the embodiments are implemented on the premise of the technical solutions of the present application, and detailed implementation methods and specific operation processes are given, but the protection scope of the present application is not limited to the following embodiments. If the specific experimental steps or conditions are not indicated in the embodiments, the operation or conditions can be performed according to the conventional experimental steps described in the prior art. If the reagents and other instruments used are not indicated by the manufacturers, they are all conventional reagent products that can be obtained from the market.

[0027] Coking wastewater has the characteristics of complex pollutant composition, high concentration of organic pollutants and high ammonia nitrogen, and is a typical refractory industrial wastewater. At present, the process of ammonia evaporation + air flotation + biochemical treatment + advanced treatment is usually used to treat coking wastewater in the market. The biochemical treatment effluent contains a large amount of refractory macromolecular organic pollutants represented by aromatic protein compounds, and the COD is usually between 150-300 mg / L, which is much higher than the industrial discharge standard. Therefore, the removal of aromatic protein compounds by the advanced treatment unit plays an important role in ensuring that the treated effluent meets the discharge standard.

[0028] The commonly used advanced treatment technologies include advanced oxidation technology, electron beam degradation technology, membrane technology and coagulation treatment technology. Among them, the advanced oxidation technology includes ozone oxidation, Fenton oxidation, etc., which mainly oxidizes organic pollutants through active species such as hydroxyl radicals generated in the system, but the selectivity of hydroxyl radical treatment of organic pollutants is poor, the utilization rate of active species is low, and a large amount of oxidizing agent needs to be consumed; the electron beam degradation technology mainly uses high-energy electron beam to irradiate wastewater to generate active species, although it does not need to add oxidizing agent, but a high irradiation dose is needed to degrade macromolecular aromatic protein compounds, and the energy consumption is high; the membrane technology mainly separates organic pollutants in wastewater through membrane filtration, which is simple to operate and also does not need to add a large amount of oxidizing agent, but after the membrane technology separates the organic pollutants, a large amount of concentrated liquid is produced, and the operation process is easily contaminated and blocked, and the actual treatment effect and theory have a large gap. The coagulation technology uses coagulants to aggregate macromolecular organic pollutants in wastewater to form flocculation bodies, so that they are separated from the wastewater, which has the advantages of good treatment effect, simple operation, mild reaction conditions, etc., and has been widely used in the advanced treatment of coking wastewater.

[0029] However, when the coagulation method is used to treat wastewater, the removal effect of organic pollutants is affected by the existence form of organic pollutants. Specifically, colloidal organic pollutants can easily aggregate into flocculation bodies and settle under the action of coagulants; and dissolved organic pollutants need to increase the coagulant dosage or use high molecular coagulant to be adsorbed on the flocculation body and then removed. Since the aromatic protein compounds in the biochemical effluent of coking wastewater exist in colloidal and dissolved states, the traditional coagulation treatment has limited treatment effect on coking wastewater, and a larger coagulant dosage is needed, which makes the cost of advanced treatment of coking wastewater higher and the treatment effect not ideal.

[0030] Therefore, the present application provides a method for treating aromatic protein compounds by irradiation, which adds ferric sulfate and ferrous sulfate in wastewater and performs electron beam irradiation treatment, and utilizes the synergistic effect of iron ions, ferrous ions and electron beam irradiation to generate and further form Fe 2+ x Fe3+ y (OH) 2x+3y ; on the one hand, the substance can promote the aggregation of colloidal organic pollutants through surface electrical neutralization, adhesion bridging, net trapping and other mechanisms; on the other hand, the empty orbital of the iron atom in the substance can also complex with the amino group in the aromatic protein compound, promoting the adsorption of dissolved aromatic protein compounds on the coagulant, thereby improving the removal effect of dissolved aromatic protein compounds; at the same time, under low irradiation dosage, the active substances generated by electron beam irradiation undergo free radical chain reactions in water, which can convert dissolved aromatic protein compounds into free radicals containing aromatic rings, which are easy to polymerize into colloidal macromolecular organic matter and easy to aggregate with coagulants; thus, through the synergistic effect of the three, the dissolved aromatic protein compounds in the coking wastewater are converted into colloidal state and removed, which requires less dosage than the coagulant such as polymeric ferric sulfate alone, and because part of the dissolved aromatic protein compounds are converted into colloidal state by the Fe 2+ x Fe 3+ y (OH) 2x+3y adsorption removal, so that the amount of polyacrylamide added is less, thus the required cost is lower, and good economic benefits are obtained.

[0031] A method for irradiation treatment of aromatic protein compounds provided by the present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0032] Referring to Figure 1 , Figure 1 A step flowchart of the method for irradiation treatment of aromatic protein compounds provided by the embodiment of the present application is shown, as shown in Figure 1 , comprising:

[0033] S1, adding a mixture of ferric sulfate and ferrous sulfate to the biochemical effluent of coking wastewater, and irradiating the biochemical effluent to obtain a pretreated liquid.

[0034] The embodiment of the present application is mainly aimed at the biochemical treatment effluent of coking wastewater, which mainly comes from the production water and steam condensate wastewater in the process of initial cooling and coking of coke oven gas, and has the characteristics of complex pollutant composition and high concentration of organic pollutants. After the biochemical treatment of coking wastewater, the treatment effluent usually contains a high concentration of aromatic protein compounds, so that the COD of the treatment effluent is high and it is difficult to meet the discharge standard. Therefore, it is particularly necessary to remove the aromatic protein compounds in the biochemical effluent of coking wastewater.

[0035] The aromatic protein compound mainly refers to a protein, a polypeptide, an amino acid and the like with an aromatic ring, and the molecular weight thereof is usually large, and the aromatic protein compound exists in a colloid state in wastewater, and a small part of the aromatic protein compound, such as an aromatic protein with high hydrophilicity, can be dissolved in wastewater, that is, in a dissolved state.

[0036] Ferrous sulfate is a commonly used flocculant, which can form a mononuclear complex by hydrolysis, reduce the potential in wastewater, adsorb the charges on the surface of part of colloids, reduce the repulsion between colloids, and thus enable the colloids to aggregate and settle. Meanwhile, divalent iron is easily oxidized to trivalent iron in wastewater, and the trivalent iron hydrolysis can obtain iron hydroxide colloid, which can form alum flowers with suspended solids in wastewater, and thus settle. The ferric sulfate can only form iron hydroxide colloid by hydrolysis to adsorb undissolved impurities in wastewater. In the present application, the iron oxide compound formed in situ based on the interaction of electron beam irradiation and ferric sulfate and ferrous sulfate in water is used to remove the aromatic protein compound.

[0037] The irradiation treatment refers to electron beam irradiation, which can introduce a high-energy electron beam to generate hydrated electrons, free radicals and other redox active species in water. The high-energy electron beam is generated by a high-energy electron accelerator, and the energy of the high-energy electron accelerator is 1.5-2 MeV.

[0038] The mass ratio of the ferric sulfate to the ferrous sulfate is 0.1-1:1, and the irradiation treatment is electron beam irradiation, and the irradiation dose of the electron beam irradiation is 1-5 kGy. It should be noted that, in the present application, the synergistic effect of iron ions, ferrous ions and electron beam irradiation is utilized to form a mixed-valence iron-containing substance Fe 2+ x Fe 3+ y (OH) 2x+3y Specifically, during the irradiation process, the iron ions and the ferrous ions form Fe under the action of the oxidizing active species generated by the irradiation. Further reaction to form Fe 2+ x Fe 3+ y (OH) 2x+3y . The Fe 2+ x Fe 3+ y (OH) 2x+3y can promote the aggregation of the aromatic protein compound in a colloid state through surface electric neutralization, adhesion bridging, net trapping and the like, and play a role of a flocculant; meanwhile, the Fe2+ x Fe 3+ y (OH) 2x+3y The empty orbital of the iron with mixed valence can also combine with the amino group in the aryl protein compound to form a complex, so that the dissolved aryl protein compound is adsorbed on the surface thereof, and then aggregated to form a flocculation body, and then removed by sedimentation. In addition, the reducing active species generated in the irradiation process can combine with Fe 2+ x Fe 3+ y (OH) 2x+3y react, so that more ferrous ions are formed on the surface thereof, and then the adsorption performance of Fe 2+ x Fe 3+ y (OH) 2x+3y is improved, so as to improve the adsorption removal effect of Fe 2+ x Fe 3+ y (OH) 2x+3y .

[0039] At the same time, under low irradiation dose, the active species generated by irradiation can initiate a free radical chain reaction, and then the dissolved aryl protein compound is converted into a free radical containing an aromatic ring, and these free radicals containing an aromatic ring are easy to aggregate to form a macromolecule, thereby converting the dissolved aryl protein compound into a colloidal state, so that the dissolved aryl protein compound is easy to be removed by flocculation.

[0040] It should be noted that any change in the dosage of iron ions, ferrous ions and irradiation dose will affect the formation of the substance containing iron with mixed valence, that is, the dosage of iron ions, the dosage of ferrous ions and the irradiation dose of irradiation treatment interact with each other, therefore, the dosage of iron ions, the dosage of ferrous ions and the irradiation dose of irradiation treatment need to be in the above proportions, so as to form Fe 2+ x Fe 3+ y (OH) 2x+3y , so as to achieve better coagulation effect of aryl protein compound.

[0041] For example, the mass ratio of the ferric sulfate and the ferrous sulfate is 0.1:1, and the irradiation dose is 1 kGy;

[0042] The mass ratio of the ferric sulfate and the ferrous sulfate is 0.3:1, and the irradiation dose is 2 kGy;

[0043] The mass ratio of the ferric sulfate and the ferrous sulfate is 0.5:1, and the irradiation dose is 3kGy.

[0044] The mass ratio of the ferric sulfate and the ferrous sulfate is 0.7:1, and the irradiation dose is 4kGy.

[0045] The mass ratio of the ferric sulfate and the ferrous sulfate is 1:1, and the irradiation dose is 5kGy.

[0046] Preferably, a mixture of the ferrous sulfate and the ferric sulfate with a mass ratio of 1:1 is used, and the irradiation dose is 1kGy, at this time, more Fe 2+ x Fe 3+ y (OH) 2x+3y The substance has a good treatment effect on aromatic protein compounds.

[0047] The ratio of the addition amount of the ferric sulfate to the COD of the coking wastewater is 1-3:1.

[0048] For example, the ratio of the addition amount of the ferric sulfate to the COD of the coking wastewater is 1:1.

[0049] The ratio of the addition amount of the ferric sulfate to the COD of the coking wastewater is 2:1.

[0050] The ratio of the addition amount of the ferric sulfate to the COD of the coking wastewater is 3:1.

[0051] S2, polyacrylamide is added to the pretreatment liquid, and after standing and precipitation, the obtained supernatant is used as the treatment effluent.

[0052] The polyacrylamide is a high-molecular coagulant and can also be used as a coagulant aid; the polyacrylamide is divided into anionic and cationic types, wherein the anionic polyacrylamide mainly adsorbs suspended solid particles in water, bridges the particles or neutralizes the charges to make the particles coagulate to form large flocs, and accelerates the sedimentation of the particles in the suspension; the cationic polyacrylamide is mainly used for flocculating colloids with negative charges; and the embodiment mainly uses the polyacrylamide to settle the colloidal aromatic protein compounds and partially aggregated aromatic protein compounds, and therefore, the anionic polyacrylamide is used as the coagulant aid and added into the wastewater.

[0053] For example, the polyacrylamide is added in an amount of 0.1 mg / L.

[0054] The polyacrylamide is added in an amount of 0.5 mg / L.

[0055] The polyacrylamide is added in an amount of 0.9 mg / L.

[0056] The polyacrylamide is added in an amount of 1.3 mg / L.

[0057] The polyacrylamide is added in an amount of 1.7 mg / L.

[0058] The polyacrylamide is added in an amount of 2 mg / L.

[0059] In the embodiment of the present application, the added polyacrylamide mainly plays a role of coagulant aid, and by adding a small amount of polyacrylamide into the coking wastewater, the colloidal aromatic protein compounds gathered with the coagulant are further gathered to form larger alum flowers and quickly settle, thereby improving the treatment effect on the aromatic protein compounds. 2+ x Fe 3+ y (OH) 2x+3y It can remove part of the aromatic protein compounds by adsorption, therefore, the polyacrylamide can be added in a relatively small amount, and the suspended flocculation body can be settled, preferably, the polyacrylamide is added in an amount of 0.1-0.5 mg / L. Within this range, the degradation of the already formed colloidal aromatic protein compounds can be ensured, and the amount of added reagent is also small, and the treatment cost is low. More preferably, 0.1 mg / L of anionic polyacrylamide is used to remove the aromatic protein compounds.

[0060] Since the polycoagulant formed after the treatment of the aromatic protein compounds by the cooperation of the ferric sulfate, ferrous sulfate and electron beam irradiation is further added with the coagulant aid polyacrylamide, the polycoagulant can be further gathered to form larger alum flowers, and then quickly settled, therefore, the settling time is not too long, and the standing and precipitation can be performed for 1-5 min.

[0061] In the present application, the mixture of ferric sulfate and ferrous sulfate is added into the biochemical effluent of the coking wastewater, and irradiation treatment is performed, so that the iron ions and ferrous ions are formed into Then, Further form Fe 2+ x Fe 3+ y (OH) 2x+3yThe substance can promote the aggregation of colloidal organic matters through surface electric neutralization, adhesion bridging, net trapping and other mechanisms, and can also promote the adsorption of aromatic protein compounds on the coagulant by complexing the amino groups in the aromatic protein compounds with the empty orbitals of iron atoms, thereby improving the adsorption removal effect. In addition, under a relatively low irradiation dose, the active species generated by electron beam irradiation can undergo a chain reaction of free radicals in water, converting the aromatic protein compounds into aromatic ring-containing free radicals, which are easy to polymerize into colloidal macromolecular organic matters, thereby promoting the mutual aggregation of the colloidal macromolecular organic matters and the coagulant into flocculating bodies. At the same time, the addition of polyacrylamide to the wastewater treated by irradiation can further promote the flocculating bodies to become large alunite flowers and rapidly settle, thus achieving a good removal effect on the aromatic protein compounds. Moreover, compared with the single addition of the coagulant, the use of ferrous sulfate, ferric sulfate and electron beam irradiation to achieve the coagulation effect requires a smaller dosage of the coagulant and a lower cost. In addition, in the process of removing the aromatic protein compounds by the synergistic effect of iron ions, ferrous ions and irradiation, the mixed valence iron-containing substances Fe 2+ x Fe 3+ y (OH) 2x+3y .

[0062] In order to enable those skilled in the art to better understand the present application, the method for irradiating and treating aromatic protein compounds in coking wastewater according to the present application is described below through a plurality of specific examples.

[0063] Example 1

[0064] A certain coking wastewater biochemical effluent was taken, and the content of the aromatic protein compounds in the wastewater was represented by the three-dimensional fluorescence intensity, as shown in FIG. A of Figure 2 The initial COD was 170±7 mg / L, the pH was 6.7, and the conductivity was 7231 μs / cm.

[0065] 1L of the above wastewater was collected in a 1.5L acid and alkali resistant container, and a mixture of 164 mg of ferric sulfate and 165 mg of ferrous sulfate was added to the coking wastewater biochemical effluent, which was stirred uniformly. Then, the biochemical effluent was irradiated and treated by an electron accelerator at an irradiation dose of 1 kGy to obtain a pretreated liquid.

[0066] 0.1 mg / L of anionic polyacrylamide was added to the pretreated liquid, and after precipitation for 5 min, the supernatant obtained was the treated effluent.

[0067] The content of the aromatic protein compounds in the treated effluent was determined, and the results are shown in FIG. B of Figure 2 According to FIG. B in the Figure 2 , the fluorescence intensity of the aromatic protein compounds in the treated effluent decreased significantly.

[0068] Example 2

[0069] A coking wastewater biochemical effluent was taken, and the content of aromatic protein compounds in the water was expressed by three-dimensional fluorescence intensity, as shown in Table A. Figure 2 The initial COD was 170±7 mg / L, the pH was 6.7, and the conductivity was 7231 μs / cm.

[0070] 1 L of the above wastewater was collected in a 1.5 L acid and alkali resistant container, and a mixture of 350 mg of ferric sulfate and 350 mg of ferrous sulfate was added to the coking wastewater biochemical effluent, which was stirred uniformly, and then the biochemical effluent was subjected to irradiation treatment by an electron accelerator at an irradiation dose of 2 kGy, to obtain a pretreated liquid.

[0071] 0.3 mg / L of anionic polyacrylamide was added to the pretreated liquid, and after 5 min of precipitation, the supernatant obtained was the treated effluent.

[0072] The content of aromatic protein compounds in the treated effluent was determined, and the results are shown in Table B. Figure 3 As can be known from Table B, the fluorescence intensity of the aromatic protein compounds in the treated effluent was significantly reduced. Figure 3

[0073] Example 3

[0074] A coking wastewater biochemical effluent was taken, and the content of aromatic protein compounds in the water was expressed by three-dimensional fluorescence intensity, as shown in Table A. Figure 2 The initial COD was 170±7 mg / L, the pH was 6.7, and the conductivity was 7231 μs / cm.

[0075] 1 L of the above wastewater was collected in a 1.5 L acid and alkali resistant container, and a mixture of 350 mg of ferric sulfate and 350 mg of ferrous sulfate was added to the coking wastewater biochemical effluent, which was stirred uniformly, and then the biochemical effluent was subjected to irradiation treatment by an electron accelerator at an irradiation dose of 2 kGy, to obtain a pretreated liquid.

[0076] 0.3 mg / L of anionic polyacrylamide was added to the pretreated liquid, and after 5 min of precipitation, the supernatant obtained was the treated effluent.

[0077] The content of aromatic protein compounds in the treated effluent was determined, and the results are shown in Table B. Figure 4 As can be known from Table B, the fluorescence intensity of the aromatic protein compounds in the treated effluent was significantly reduced. Figure 4

[0078] Example 4

[0079] Tryptophan was used as a target aromatic protein compound to prepare a simulated wastewater, and the addition amount of tryptophan was controlled so that the initial COD of the simulated wastewater was 100 mg / L.​​

[0080] Take 1L of the above simulated wastewater, add 100 mg of ferric sulfate and 100 mg of ferrous sulfate to the simulated wastewater, stir evenly, then use an electron accelerator to irradiate the biochemical effluent with an irradiation dose of 1 kGy to obtain a pretreated liquid.

[0081] Add 0.1 mg / L of anionic polyacrylamide to the pretreated liquid, and after 5 minutes of precipitation, the supernatant obtained is the treated effluent.

[0082] By detecting the COD content in the treated effluent, the content of aromatic protein compounds in the treated effluent is determined, and the detection results show that the COD of the simulated wastewater is reduced to 20 mg / L, and the removal rate of aromatic protein compounds can reach 80%.

[0083] Example 5

[0084] Take 1L of the above simulated wastewater, add 100 mg of ferric sulfate and 100 mg of ferrous sulfate to the simulated wastewater, stir evenly, then use an electron accelerator to irradiate the biochemical effluent with an irradiation dose of 1 kGy to obtain a pretreated liquid.

[0085] Add 0.1 mg / L of anionic polyacrylamide to the pretreated liquid, and after 5 minutes of precipitation, the supernatant obtained is the treated effluent.

[0086] Add 0.1 mg / L of anionic polyacrylamide to the pretreated liquid, and after 5 minutes of precipitation, the supernatant obtained is the treated effluent.

[0087] By detecting the COD content in the treated effluent, the content of aromatic protein compounds in the treated effluent is determined, and the detection results show that the COD of the simulated wastewater is reduced to 20 mg / L, and the removal rate of aromatic protein compounds can reach 80%.

[0088] Example 6

[0089] Take 1L of the above simulated wastewater, add 100 mg of ferric sulfate and 100 mg of ferrous sulfate to the simulated wastewater, stir evenly, then use an electron accelerator to irradiate the biochemical effluent with an irradiation dose of 1 kGy to obtain a pretreated liquid.

[0090] Take 1L of the above simulated wastewater, add 100 mg of ferric sulfate and 100 mg of ferrous sulfate to the simulated wastewater, stir evenly, then use an electron accelerator to irradiate the biochemical effluent with an irradiation dose of 1 kGy to obtain a pretreated liquid.

[0091] Add 0.1 mg / L of anionic polyacrylamide to the pretreated liquid, and after 5 minutes of precipitation, the supernatant obtained is the treated effluent.

[0092] By detecting the COD content in the treated effluent, the content of aromatic protein compounds in the treated effluent is determined, and the detection result shows that the COD of the simulated wastewater is reduced to 10 mg / L, and the removal rate of aromatic protein compounds can reach 90%.

[0093] Comparative Example 1

[0094] Tryptophan is used as a target aromatic protein compound to prepare simulated wastewater, and the amount of tryptophan added is controlled so that the initial COD of the simulated wastewater is 100 mg / L.

[0095] 1L of the above simulated wastewater is taken, and 150 mg of ferric sulfate and 300 mg of ferrous sulfate are added to the simulated wastewater to obtain a pretreated liquid.

[0096] 0.5 mg / L of anionic polyacrylamide is added to the pretreated liquid, and after 5 min of precipitation, the supernatant obtained is the treated effluent.

[0097] By detecting the COD content in the treated effluent, the content of aromatic protein compounds in the treated effluent is determined, and the detection result shows that the COD of the simulated wastewater is reduced to 54 mg / L, and the removal rate of aromatic protein compounds is 54%.

[0098] From the results of the examples and the comparative example, it can be seen that the irradiation cooperates with ferric sulfate and ferrous sulfate to flocculate aromatic protein compounds, and the effect is better than that of ferric sulfate and ferrous sulfate alone, and thus the irradiation significantly improves the treatment effect of the mixture of ferric sulfate and ferrous sulfate on aromatic protein compounds.

[0099] The method for treating aromatic protein compounds by irradiation provided in the examples of the present application first adds a mixture of ferric sulfate and ferrous sulfate, and then performs electron beam irradiation treatment, and based on the synergistic effect of ferric sulfate, ferrous sulfate and electron beam irradiation, a substance Fe 2+ x Fe 3+ y (OH) 2x+3y , which has a mixed valence, adsorbs and removes dissolved aromatic protein compounds, and also promotes the aggregation of colloidal aromatic protein compounds into flocculation bodies, which are then settled under the action of polyacrylamide, and thus the method for coagulating and removing aromatic protein compounds by the synergistic effect of ferric sulfate, ferrous sulfate and electron beam irradiation provided in the examples of the present application has a good overall treatment effect on aromatic protein compounds in the biochemical effluent of coking wastewater; at the same time, the amount of ferric sulfate, ferrous sulfate and polyacrylamide added is lower than the amount of reagent required for coagulation with a single reagent, the cost is lower, and the treatment time is short, so that the aromatic protein compounds in the coking wastewater can be efficiently coagulated.

[0100] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application, any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application should be included in the protection scope of the present application.

[0101] For the method embodiments, in order to simply describe, they are all expressed as a series of action combinations, but the skilled in the art should know that the present application is not limited by the action sequence described, because according to the present application, some steps can be in other sequence or simultaneously. Secondly, the skilled in the art should know that the embodiments described in the specification all belong to the preferred embodiments, and the actions and components involved are not necessarily the necessary of the present application.

[0102] The above describes in detail the method for irradiating aromatic protein compounds in coking wastewater provided by the present application, the principle and implementation mode of the present application are described by applying specific examples, the above embodiment description is only for helping to understand the method of the present application and its core idea; at the same time, for the general skilled in the art, according to the idea of the present application, the specific implementation mode and application scope will have changes, and the above description should not be understood as limiting the present application.

Claims

1. A method for irradiating aromatic protein compounds in coking wastewater, characterized in that, The method includes: Step 1: A mixture of ferric sulfate and ferrous sulfate is added to the biochemical effluent of coking wastewater, and the biochemical effluent is subjected to irradiation treatment to obtain a pretreated solution, wherein the pretreated solution includes Fe. 2+ x Fe 3+ y (OH) 2x+3y The mass ratio of ferric sulfate to ferrous sulfate is 0.1-1:

1. Step 2: Add polyacrylamide to the pretreatment solution, allow it to settle, and use the resulting supernatant as the treated effluent; wherein the dosage of polyacrylamide is 0.1-2 mg / L. The polyacrylamide is anionic polyacrylamide.

2. The method for irradiating aromatic protein compounds in coking wastewater according to claim 1, characterized in that, The ratio of the amount of ferric sulfate added to the COD of the coking wastewater is 1-3:

1.

3. The method for irradiating aromatic protein compounds in coking wastewater according to claim 1, characterized in that, The irradiation dose for the irradiation treatment is 1-5 kGy.

4. The method for irradiating aromatic protein compounds in coking wastewater according to claim 1, characterized in that, The dosage of the polyacrylamide is 0.1-0.5 mg / L.

5. The method for irradiating aromatic protein compounds in coking wastewater according to claim 1, characterized in that, The settling time is 1-5 minutes.

6. The method for irradiating aromatic protein compounds in coking wastewater according to claim 1, characterized in that, The irradiation treatment is electron beam irradiation, which is performed using an electron accelerator.

7. The method for irradiating aromatic protein compounds in coking wastewater according to claim 2, characterized in that, The ratio of the amount of ferric sulfate added to the COD of the coking wastewater is 1:

1.

8. The method for irradiating aromatic protein compounds in coking wastewater according to claim 3, characterized in that, The irradiation dose for the irradiation treatment is 1 kGy.

9. The method for irradiating aromatic protein compounds in coking wastewater according to claim 4, characterized in that, The dosage of the polyacrylamide is 0.1 mg / L.

10. The method for irradiating aromatic protein compounds in coking wastewater according to claim 1, characterized in that, The mass ratio of ferrous sulfate to ferric sulfate is 1:1.

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