阅读说明：本技术 一种芬顿反应催化剂、制备方法及基于该催化剂的芬顿反应器及垃圾渗滤液全量化处理方法 (Fenton reaction catalyst, preparation method, Fenton reactor based on catalyst and garbage leachate full-quantitative treatment method ) 是由 周甜 曹兴 黄敏 全邦宇 罗雅婧 陈金煊 蔡昕彤 朱晋荣 周伊丹 黄明辉 郭莉 于 2020-09-15 设计创作，主要内容包括：本发明涉及一种芬顿反应催化剂、制备方法以及基于该催化剂的芬顿反应器及垃圾渗滤液全量化处理方法,属于污水处理领域。所述芬顿反应催化剂的催化活性成分包括：ZnS、PbS、Co<Sub>3</Sub>S<Sub>4</Sub>。本发明还提供基于所述芬顿反应催化剂的芬顿反应器及垃圾渗滤液全量化处理方法。本发明的芬顿反应催化剂、芬顿反应器及垃圾渗滤液全量化处理方法可高效降低垃圾渗滤液中的COD值。(The invention relates to a Fenton reaction catalyst, a preparation method, a Fenton reactor based on the catalyst and a full-quantitative treatment method of landfill leachate, and belongs to the field of sewage treatment. The catalytic active components of the Fenton reaction catalyst comprise: ZnS, PbS, Co 3 S 4 . The invention also provides a Fenton reactor based on the Fenton reaction catalyst and a full-quantitative treatment method of landfill leachate. The Fenton reaction catalyst, the Fenton reactor and the garbage leachate full-quantitative treatment method can efficiently reduceLow COD value in the landfill leachate.)

1. A Fenton reaction catalyst, characterized in that its catalytically active components comprise: ZnS, PbS and Co with the mass ratio of 3-5: 1-2: 0.5₃S₄。

2. A fenton reaction catalyst according to claim 1, wherein ZnS, PbS, Co₃S₄The mass ratio of the components is 3: 1: 0.5;

preferably, the ZnS is hydrosulfuric acid-modified sphalerite particles;

preferably, the PbS is a hydrosulfuric acid modified galena particles;

preferably, the Co₃S₄Is a cobaltite particle modified by hydrosulfuric acid;

preferably, the particle size of the hydrosulfuric acid modified sphalerite particles, the hydrosulfuric acid modified galena particles and the hydrosulfuric acid modified cobaltite particles is selected from 0.1 mm-4 mm.

3. The preparation method of the Fenton reaction catalyst is characterized in that ZnS, PbS and Co are mixed₃S₄Mixing according to the mass ratio of 1-3: 1-2: 0.5-1.

4. A method for preparing a Fenton reaction catalyst according to claim 3, wherein ZnS, PbS, Co are mixed₃S₄According to the mass ratio of 3Mixing the components in a ratio of 1: 0.5;

preferably, the galena, the sphalerite and the cobaltite are respectively subjected to modification by hydrosulfuric acid, flotation and sieving to obtain ZnS, PbS and Co₃S₄Mixing the granules again;

preferably, the galena, blende and skutterudite are newly produced raw ores of the mine.

5. A method for preparing a Fenton reaction catalyst according to claim 4, wherein before the modification with hydrogen sulfuric acid, the mineral is pulverized;

preferably, the hydrosulfuric acid-modified flotation means: adding hydrogen sulfuric acid into the crushed minerals;

preferably, the minerals floated by the modification of the hydrogen sulfuric acid are respectively washed by absolute ethyl alcohol and pure water and then dried for 24 hours at the temperature of 50-80 ℃;

preferably, the dried mineral is sieved sequentially through 5 mesh, 18 mesh, 50 mesh and 140 mesh sieves to obtain the following 3 particle size ranges, respectively: 1mm to 4mm, 0.3 to 1mm and 0.1 to 0.3mm of ore particles;

preferably, the mixing refers to mixing three ore particles belonging to the same grain size range.

6. A fenton reactor comprising a catalyst packing unit located inside the reactor; the catalyst filler unit comprises an upper layer, a middle layer and a lower layer of 3 catalyst particle layers, and the particle size of each layer of catalyst particle is increased from top to bottom in sequence;

the catalyst comprises ZnS, PbS and Co with the mass ratio of 3-5: 1-2: 0.5₃S₄。

7. A Fenton reactor according to claim 6, wherein the particle size of the catalyst particles in the upper catalyst particle layer is 0.1 to 0.3mm, the particle size of the catalyst particles in the middle catalyst particle layer is 0.3 to 1mm, and the particle size of the catalyst particles in the lower catalyst particle layer is 1 to 4 mm;

preferably ZnS, PbS, Co₃S₄The mass ratio of the components is 3: 1: 0.5;

preferably, the catalyst particles may be placed in a filter bag;

preferably, the filter bag is in a circular ring structure after being filled with catalyst particles;

preferably, the Fenton reactor is of a reaction tank structure with a hollow interior; a fixing component capable of fixing the catalyst particle layer is arranged in the reaction tank;

preferably, the fixing part is a fixing column arranged on the inner wall of the bottom of the reaction tank; the annular filter bag filled with the catalyst particles can be sleeved on the fixed column; the size and the shape of the circular filter bag filled with the catalyst particles are matched with the inner part of the reaction tank;

preferably, a clamping groove is formed in the center of the inner wall of the bottom of the reaction tank; the fixing column can be clamped in the clamping groove;

preferably, 3 circular filter bags filled with catalyst particles are arranged, and correspond to the upper, middle and lower 3 catalyst particle layers respectively;

preferably, the number of the catalyst packing units is 1, 2 or more;

preferably, a feed inlet and a discharge outlet are formed in the wall of the reaction tank, and the top of the reaction tank can be opened and is provided with a top cover capable of being opened and closed;

preferably, the height of the catalyst packing elements is from 5 to 20 cm.

8. A fenton reaction catalyst according to claim 1 or 2, and/or a fenton reaction catalyst obtained by the method according to any one of claims 3 to 5, and/or a fenton reactor according to claim 7 or 8 for use in treating organic contamination.

9. A method for fully treating landfill leachate, which is characterized in that the fenton reaction catalyst according to claim 1 or 2, and/or the fenton reaction catalyst obtained by the preparation method according to any one of claims 3 to 5, and/or the fenton reactor according to claim 7 or 8 is used for treating the landfill leachate.

10. The method of claim 9, wherein the Fenton reaction reagent is FeSO₄·7H₂O and H₂O₂；

Preferably, the FeSO₄·7H₂O is 2-12mmol/L, H₂O₂Is 100-600 mmol/L;

more preferably, the reaction system has a pH of 3 to 5;

preferably, the addition amount of the catalyst particles in the catalyst packing unit is 6-10 g/L.

Technical Field

The invention belongs to the field of sewage treatment, and particularly relates to a Fenton reaction catalyst, a preparation method of the Fenton reaction catalyst, a Fenton reactor based on the Fenton reaction catalyst, and a full-quantitative treatment method of landfill leachate.

Background

The full-quantitative treatment technology of the landfill leachate is a trend of future leachate treatment, and can effectively solve a series of problems caused by recharging membrane concentrated solution after the treatment of biochemical and membrane technologies and full-membrane technologies in the conventional technologies for a long time. Compared with the existing 'evaporation and solidification' process, the 'biochemical and Fenton' operation cost is lower.

Advanced Oxidation Processes (AOPs) mainly include a Fenton method and a Fenton-like method, and the Fenton method is a common Advanced Oxidation technology for biochemical treatment units of leachate, and can effectively remove organic pollutants in the leachate. In the Fenton reaction, H₂O₂Has a low decomposition efficiency even if Fe is added²⁺The decomposition efficiency is still low, so that a large amount of H is required₂O₂And catalysts, making their use on a large scale in wastewater treatment prohibitively expensive. In a practical industrial environment, large quantities are often requiredFe (b) of^{2 +}And H₂O₂Sufficient concentration of OH can be generated. Furthermore, the Fenton reaction Fe³⁺To Fe²⁺Much lower than Fe²⁺To Fe³⁺The rate of conversion. Therefore, excessive Fe is generated³⁺Ions, leading to the formation of sludge (iron cement) and thus to catalyst poisoning. On the other hand, too much hydrogen peroxide used in AOP corrodes equipment and greatly increases operating costs.

By adding various materials as "promoters" to enhance the production of OH, although much effort has been made to optimize AOP, particularly to optimize Fe³⁺To Fe²⁺Efficiency of the conversion. However, almost all previous reports on the promoted AOP have focused on the use of organic compounds as promoters, which are prone to secondary pollution and difficult to completely mineralize organic molecules.

The Fenton method is an important part of common full-scale treatment technology of the percolate at present, but the traditional Fenton method has the problems of low efficiency, high iron mud yield and the like. In addition, the water quantity change of the percolate is large along with the change of seasons, and the traditional Fenton method is difficult to meet the treatment requirement of the percolate.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the prior art, and provide a Fenton reaction catalyst which can improve the Fenton reaction efficiency, reduce the dosage of a Fenton reagent, has few byproducts and does not produce exudation toxicity: the fixed hydrosulfuric acid modified metal mineral Fenton reaction catalyst also provides a preparation method of the fixed hydrosulfuric acid modified metal mineral Fenton reaction catalyst, which is simple in preparation process, easy in raw material obtaining and low in cost, and an application of the fixed hydrosulfuric acid modified metal mineral Fenton reaction catalyst in the aspect of strengthening the Fenton method for treating landfill leachate.

In order to solve the technical problems, the invention adopts the following technical scheme:

a Fenton reaction catalyst, characterized in that its catalytically active components comprise: ZnS, PbS, Co₃S₄。

The above-mentionedZnS, PbS, Co of₃S₄The mass ratio is 3-5: 1-2: 0.5, preferably 3: 1: 0.5;

because the Fenton treatment is arranged at the back end of the biochemical treatment, biochemical effluent can bring a small part of activated sludge, and the invention adopts minerals with different catalytic activities for proportioning, thereby not only playing a catalytic role, but also playing roles in adsorption and filtration.

From the catalytic effect of the individual substances, the catalytic effect: ZnS < PbS < Co₃S₄The content of the substances is reduced in sequence by combining the availability and the material cost of the raw materials; the catalyst has relatively poor catalytic effect, and can play a role in filling, so that the thickness of the filler layer can be ensured, and the filler layer has sufficient filtering and adsorbing effects.

From the comprehensive use effect, the technical embodiment of the invention is provided with two catalyst filler units (also equivalent to the filler layer), and a single catalyst filler unit contains 3 layers of catalysts (also equivalent to the filler) with different particle sizes, so that the effects of gradient filtration, layer-by-layer catalysis and full contact of the catalysts and wastewater are achieved, the filler blockage can be relieved, and the filler backwashing time is prolonged.

The ZnS that catalytic activity is low accounts for than big, because catalytic activity is low, can lean on increasing the quantity to reach the effect, bring certain filling effect when increasing the quantity, make the packing layer can possess ideal thickness, extension contact time and area of contact, the mineral that this catalytic activity is low is easily obtained, the source is relatively more extensive, otherwise do not add this material, full-purpose catalytic activity is good, the catalyst quantity is very low, packing layer thickness is not enough, not both reach better filter effect, can not play the effect of extension contact time again, on the contrary not so good effect.

Preferably, the ZnS is hydrosulfuric acid-modified sphalerite particles;

preferably, the PbS is a hydrosulfuric acid modified galena particles;

preferably, the Co₃S₄Is a cobaltite particle modified by hydrosulfuric acid;

preferably, the particle size of the hydrosulfuric acid modified sphalerite particles, the hydrosulfuric acid modified galena particles and the hydrosulfuric acid modified cobaltite particles is selected from 0.1 mm-4 mm.

The preparation method of the Fenton reaction catalyst is characterized in that ZnS, PbS and Co are mixed₃S₄And (4) mixing.

Mixing ZnS, PbS and Co₃S₄Mixing at a mass ratio of 3-5: 1-2: 0.5, preferably 3: 1: 0.5;

preferably, the galena, the sphalerite and the cobaltite are respectively subjected to modification by hydrosulfuric acid, flotation and sieving to obtain ZnS, PbS and Co₃S₄Mixing the granules again;

preferably, the galena, blende and skutterudite are newly produced raw ores of the mine.

Theoretically commercially available ZnS, PbS, Co₃S₄But also can play a role in catalysis, but because the components have high purity and high cost and are powdery, the addition amount is small, a packing layer with proper particle size and proper thickness cannot be obtained, the components cannot be loaded by particles with different particle sizes like the invention patent, not only can play a role in catalysis, but also can play a role in adsorption filtration, and can reduce the content of iron sludge and other suspended matters in Fenton effluent.

The effect of the modification with hydrogen sulfuric acid is to remove mainly other metal oxides entrained in the sulphide ores in the ore, so that the surface of the ore has a higher amount of metal sulphides.

Before the modification of the hydrosulfuric acid, the minerals need to be crushed;

preferably, the hydrosulfuric acid-modified flotation means: adding hydrogen sulfuric acid into the crushed minerals;

preferably, the minerals floated by the modification of the hydrogen sulfuric acid are respectively washed by absolute ethyl alcohol and pure water and then dried for 24 hours at the temperature of 50-80 ℃;

preferably, the dried mineral is sieved sequentially through 5 mesh, 18 mesh, 50 mesh and 140 mesh sieves to obtain the following 3 particle size ranges, respectively: 1mm to 4mm, 0.3 to 1mm and 0.1 to 0.3mm of ore particles;

preferably, the mixing refers to mixing three ore particles belonging to the same grain size range.

A fenton reactor comprising a catalyst packing unit located inside the reactor; the catalyst filler unit comprises an upper layer, a middle layer and a lower layer of 3 catalyst particle layers, and the particle size of each layer of catalyst particle is increased from top to bottom in sequence;

the catalyst comprises ZnS, PbS and Co₃S₄。

The particle size of the catalyst particles of the upper catalyst particle layer is 0.1-0.3 mm, the particle size of the catalyst particles of the middle catalyst particle layer is 0.3-1 mm, and the particle size of the catalyst particles of the lower catalyst particle layer is 1-4 mm;

preferably ZnS, PbS, Co₃S₄The mass ratio of (A) to (B) is as follows: 3-5: 1-2: 0.5, preferably 3: 1: 0.5;

the particle layers with different particle sizes are arranged, so that on one hand, the retention time of the percolate and the Fenton reagent in the mineral layer can be increased, and the contact area of the pollutants, the Fenton reagent and the sulfide minerals is increased so as to more efficiently treat the pollutants; on the other hand down to the arrangement that the particle size reduces in proper order, with rivers direction unanimity (the rivers direction is down advances upward out), played the effect of gradient filtration, can reduce the jam of packing layer like this, can reduce the content of the suspension of fenton play water through multilayer filtration.

Preferably, the catalyst particles may be placed in a filter bag;

preferably, the filter bag is in a circular ring structure after being filled with catalyst particles;

preferably, the Fenton reactor is of a reaction tank structure with a hollow interior; a fixing component capable of fixing the catalyst particle layer is arranged in the reaction tank;

preferably, the fixing part is a fixing column arranged on the inner wall of the bottom of the reaction tank; the annular filter bag filled with the catalyst particles can be sleeved on the fixed column; the size and the shape of the circular filter bag filled with the catalyst particles are matched with the inner part of the reaction tank;

preferably, a clamping groove is formed in the center of the inner wall of the bottom of the reaction tank; the fixing column can be clamped in the clamping groove;

preferably, 3 circular filter bags filled with catalyst particles are arranged, and correspond to the upper, middle and lower 3 catalyst particle layers respectively;

preferably, the number of the catalyst packing units is 1, 2 or more;

preferably, a feed inlet and a discharge outlet are formed in the wall of the reaction tank, and the top of the reaction tank can be opened and is provided with a top cover capable of being opened and closed;

preferably, the height of the catalyst packing elements is from 5 to 20 cm.

The Fenton reaction catalyst and/or the Fenton reaction catalyst obtained by the preparation method and/or the application of the Fenton reactor in treating organic pollution.

The full-quantitative treatment method of the landfill leachate is characterized in that the Fenton reaction catalyst is adopted, and/or the Fenton reaction catalyst obtained by the preparation method is adopted, and/or the Fenton reactor is used for treating the landfill leachate.

The Fenton reaction reagent is FeSO₄·7H₂O and H₂O₂；

Preferably, the FeSO₄·7H₂O is 2-12mmol/L, H₂O₂Is 100-600 mmol/L;

more preferably, the reaction system has a pH of 3 to 5;

preferably, the addition amount of the catalyst particles in the catalyst packing unit is 6-10 g/L.

Comparative example 4 of the present invention shows that too few catalyst particles reduce the efficiency of Fenton degradation of COD. Too much is uneconomical and occupies space, and the catalyst can reach the standard when the concentration is 6-10g/L, namely the total amount of the catalyst particles of each liter of reaction reagent in each reaction system is 6-10 g.

Aiming at the defects or improvement requirements of the existing Fenton technology, the invention provides a Fenton technology enhancement method for full-quantitative treatment of landfill leachate, wherein the organic pollutants in the leachate can be efficiently degraded by the oxidation of the catalytic Fenton reaction through the preparation and layered immobilization of key hydrosulfuric acid modified metal particles. The method can effectively overcome the defects of slow reaction rate, large usage amount of Fenton reagent and large generation amount of iron mud in the prior art, not only can remarkably improve the Fenton reaction rate, but also can reduce the treatment cost of the percolate. In addition, the raw materials of the hydrogen sulfuric acid modified metal particles are easy to obtain, the cost is low, and the particle preparation process is very simple. Moreover, the catalyst is wrapped by a filter bag and fixed in a Fenton tank reaction area in a layered mode, so that the catalysis assisting effect can be effectively controlled to be exerted stably, and leaching toxicity is not generated. In addition, the prepared hydrosulfuric acid modified mineral particles have longer service life and do not need to be replaced frequently. In the invention, the organic pollutants in the leachate are degraded by using the hydrogen sulfuric acid modified metal particles to assist in catalysis, and an effective improvement way is provided for treating the leachate by a Fenton method.

Drawings

Fig. 1 is a schematic diagram of a reaction apparatus for catalytic fenton treatment of leachate according to one embodiment of the present invention. The labels in the figure are listed below: 1-a feed inlet (a water inlet pipe), 2-a lower catalyst particle layer, 3-a middle catalyst particle layer, 4-an upper catalyst particle layer, 5-the inside of a reaction tank, 6-a fixed column, 7-the top of the reaction tank, 8-a discharge outlet (a water outlet pipe), 9-a vent pipe and 10-a clamping groove.

FIG. 2 is a schematic diagram of the Fenton reaction catalyst of the present invention for catalyzing the Fenton reaction to treat leachate.

FIG. 3 is a diagram showing the effect of removing COD from leachate of different experimental examples and comparative examples of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the embodiments of the present invention and the accompanying drawings. The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention.