Iron-carbon micro-electrolysis filler taking sludge and micro-plastic as raw materials, preparation method and application thereof

Abstract

The application provides an iron-carbon micro-electrolysis filler taking sludge and micro-plastic as raw materials, a preparation method and application thereof, and belongs to the technical field of solid waste resource utilization. The filler is prepared from sludge powder, micro-plastic, reduced iron powder and bentonite, and a water solution containing glucose is used in granulation. After successful molding, calcination is performed, and the sludge and micro-plastic provide the filler with rich porous structure in the carbonization process, so that the filler has higher specific surface area and good performance. The preparation method of the filler is low in cost, simple and easy to operate, the prepared product is stable in performance, and has wide application range. Meanwhile, the method realizes resource utilization of sludge and low-cost purification of wastewater, achieves the purpose of waste control by waste, and provides a cheap and efficient filler for treatment of antimony-containing wastewater.

Description

Technical Field

[0001] This invention relates to an iron-carbon micro-electrolysis filler made from sludge and microplastics, its preparation method and application, belonging to the field of solid waste resource utilization technology. Background Technology

[0002] With the rapid urbanization and industrialization in my country, the production of sludge from wastewater treatment plants has also increased. Sludge is complex in composition, rich in heavy metals, recalcitrant organic matter, and pathogenic microorganisms. In recent years, microplastics, as an emerging pollutant, have become ubiquitous, and their accumulation and long-term presence in the environment can harm ecosystems. Traditional sludge and plastic disposal methods cannot perfectly address the harm they cause and may even lead to secondary pollution. Therefore, we urgently need to develop a low-cost and green method for the treatment and reuse of sludge.

[0003] Studies have found that sludge and microplastics can both serve as carbon sources for synthetic carbon materials. If the carbon from sludge and microplastics can be combined with iron to replace activated carbon, and then processed through a one-step high-temperature calcination method, sludge-based iron-carbon microelectrolysis materials can be prepared. This not only transforms sludge and microplastics into functional carbon but also successfully replaces expensive activated carbon as the carbon framework material for iron-carbon microelectrolysis. The interaction between the two can remove recalcitrant organic matter and heavy metals from wastewater, improving wastewater treatment efficiency.

[0004] The textile and dyeing industries, as pillars of my country's industrial economy, generate large volumes of wastewater with complex compositions. This wastewater often contains significant amounts of the recalcitrant heavy metal antimony, which is known for its mutagenic, carcinogenic, and teratogenic properties, posing a considerable threat to human health. Furthermore, my country's discharge standards for antimony-containing wastewater have been continuously tightening in recent years. This presents a substantial challenge for these developing industries. Therefore, developing a green and efficient method for treating antimony-containing wastewater is of paramount importance. Summary of the Invention

[0005] The purpose of this invention is to solve the problem of high Sb content in industrial wastewater and its difficulty in removal in the prior art.

[0006] To address the aforementioned problems, the present invention provides an iron-carbon microelectrolysis filler made from sludge and microplastics, its preparation method, and its application.

[0007] In a first aspect, the present invention provides a method for preparing an iron-carbon microelectrolysis filler using sludge and microplastics as raw materials, comprising the following steps:

[0008] Step 1: Grind the dried sludge into powder, sieve it, weigh the sludge powder, microplastics recovered from the wastewater, reduced iron powder and bentonite, add an aqueous solution containing glucose to obtain the molded water-containing filler.

[0009] Step 2: After drying the shaped water-containing filler obtained in Step 1, transfer it to a tube furnace with a vent valve. Under an argon atmosphere, heat the tube furnace to 500℃~700℃ and maintain it at this temperature for 3 hours. Then cool it to room temperature to obtain the prepared iron-carbon micro-electrolysis filler.

[0010] Preferably, in step 1, the mass of bentonite accounts for 20% to 30% of the total mass; the mass ratio of reduced iron powder, sludge powder and microplastics is (5 to 10): (1 to 5): 1.

[0011] Preferably, in step 1, the concentration of the glucose-containing aqueous solution is 5–10 g / L.

[0012] Preferably, in step 2, the heating rate of the tubular furnace is 10°C / min.

[0013] In a second aspect, the present invention provides an iron-carbon microelectrolysis filler prepared by the above method, using sludge and microplastics as raw materials;

[0014] A third aspect of the present invention provides a method for applying the above-mentioned iron-carbon micro-electrolysis filler made from sludge and microplastics, comprising the following steps:

[0015] Step 1: Pre-treat industrial wastewater containing heavy metal Sb from dyeing and printing wastewater through microfiltration.

[0016] Step 2: Add the prepared iron-carbon micro-electrolysis filler into the simulated wastewater;

[0017] Step 3: Aerate the simulated wastewater in the beaker to further improve the treatment efficiency of the packing material.

[0018] Preferably, in step 1, the concentration of heavy metal Sb is 500–4000 μg / L; the pH range of the simulated wastewater is 3–11; and the treatment time is 1.5 h.

[0019] Preferably, in step 2, the dosage of the iron-carbon micro-electrolysis filler is 1-5 g / L.

[0020] Preferably, in step 3, the device for performing low-concentration aeration treatment of 0-2 mg / L is an adjustable oxygenation pump.

[0021] Preferably, after the application is completed, the iron-carbon micro-electrolysis filler is rinsed with tap water for recycling.

[0022] Preferably, the number of cyclic simulations is 10.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. An iron-carbon micro-electrolysis packing material was obtained using iron-containing sludge and microplastics as raw materials and bentonite as a binder. During high-temperature calcination, the sludge and microplastics can be carbonized, serving as a carbon source. This carbonization process also imparts a rich porous structure to the packing material, increasing its specific surface area. Simultaneously, the light hydrocarbons produced by the pyrolysis of microplastics can reduce the metal elements present in the sludge. These metal elements, along with reduced iron powder, act as templates to catalyze the carbonization of the microplastics, further improving the packing material's electrical conductivity.

[0025] 2. This packing material preparation method is low-cost, simple, and easy to operate. The prepared product has stable performance and a wide range of applications. Simultaneously, this method achieves resource utilization of sludge and low-cost wastewater purification, realizing the goal of treating waste with waste, and providing a low-cost and efficient packing material for the treatment of dyeing and printing wastewater. Attached Figure Description

[0026] Figure 1 This is a SEM image of the porous structure of the iron-carbon microelectrolysis filler prepared in Example 1;

[0027] Figure 2 This demonstrates the effect of the iron-carbon micro-electrolysis filler prepared in Example 2 on Sb removal at different pH values.

[0028] Figure 3 This demonstrates the effect of the iron-carbon micro-electrolysis filler prepared in Example 2 on Sb removal under different Sb concentrations;

[0029] Figure 4 This is a graph showing the recycling performance of the iron-carbon micro-electrolysis filler prepared in Example 3;

[0030] Figure 5 This is a comparison chart of the performance of the iron-carbon micro-electrolysis filler prepared in Example 4 and commercially available iron-carbon materials;

[0031] Figure 6 This is a flowchart illustrating the preparation of an iron-carbon microelectrolysis filler made from sludge and microplastics, and its application. Detailed Implementation

[0032] To make the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings:

[0033] like Figure 1-6 As shown, the present invention provides a method for preparing an iron-carbon microelectrolysis filler using sludge and microplastics as raw materials.

[0034] Example 1:

[0035] The prepared iron-carbon micro-electrolysis filler was formulated according to the following ratio: bentonite accounted for 30% of the total mass; the mass ratio of reduced iron powder, sludge powder, and microplastics was 10:5:1. A 10 g / L glucose solution was used for molding. After molding, the filler was calcined in a tube furnace at a heating rate of 10 °C / min to 700 °C for 3 hours to solidify.

[0036] Example 2:

[0037] The removal efficiency of the prepared iron-carbon micro-electrolysis packing material for Sb was simulated under different pH and Sb concentration conditions. The simulated wastewater pH ranges were set to 3, 5, 7, 9, and 11; the Sb concentrations were set to 500 μg / L, 1000 μg / L, 2000 μg / L, and 4000 μg / L. After 1.5 h of treatment, under different pH conditions, the removal efficiency of 5 g / L iron-carbon micro-electrolysis packing material for Sb-containing wastewater with a concentration of 500 μg / L remained above 95%; and under different Sb concentration ranges, the iron-carbon micro-electrolysis packing material also maintained a removal rate of at least 94%.

[0038] Example 3:

[0039] The removal efficiency of the prepared iron-carbon micro-electrolysis packing material for Sb was simulated after 10 cycles of use. 5 g / L of the iron-carbon micro-electrolysis packing material was aerated at an Sb concentration of 500 μg / L for 3 hours, followed by washing with water, and then the next round of experiments was conducted. After ten simulated cycles, the prepared sludge-based iron-carbon micro-electrolysis packing material still maintained an 87% removal efficiency for Sb.

[0040] Example 4:

[0041] The performance of the prepared iron-carbon micro-electrolysis packing material was compared with that of commercially available materials. The iron-carbon micro-electrolysis packing material, two commercially available iron-carbon materials, and reduced iron powder were respectively subjected to aeration treatment at a Sb concentration of 500 μg / L. After 1 hour of treatment, it was found that the prepared sludge-based iron-carbon micro-electrolysis packing material had the best treatment performance at a lower cost. The cost ranking was: commercial iron-carbon packing material II < iron-carbon micro-electrolysis packing material prepared in this patent < commercial iron-carbon packing material I < reduced iron powder. The specific prices were 5.8 yuan / kg, 6.8 yuan / kg, 10 yuan / kg, and 19 yuan / kg, respectively. In terms of treatment efficiency, after treatment, the iron-carbon micro-electrolysis packing material prepared in this patent achieved a Sb removal rate of 99.2%; the commercial iron-carbon packing material achieved a removal rate of 38.1%; the commercial iron-carbon packing material II achieved a removal rate of 22.2%; and the reduced iron powder achieved a removal rate of 11.2%.

[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention. Any modifications, alterations, and equivalent changes made by those skilled in the art based on the above-disclosed technical content without departing from the spirit and scope of the present invention are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing an iron-carbon microelectrolysis filler using sludge and microplastics as raw materials, characterized in that, Includes the following steps: Step 1: Grind the dried sludge into powder, sieve it, weigh the sludge powder, microplastics recovered from the wastewater, reduced iron powder and bentonite, add an aqueous solution containing glucose to obtain the molded water-containing filler. Step 2: After drying the shaped water-containing filler obtained in Step 1, transfer it to a tube furnace with a vent valve. Under an argon atmosphere, heat the tube furnace to 500℃~700℃ and maintain it at this temperature for 3 hours. Then cool it to room temperature to obtain the prepared iron-carbon micro-electrolysis filler. In step 1, the mass of bentonite accounts for 20% to 30% of the total mass; the mass ratio of reduced iron powder, sludge powder and microplastics is (5 to 10):(1 to 5):1; and the concentration of the glucose-containing aqueous solution is 5 to 10 g / L.

2. An iron-carbon microelectrolysis filler prepared by the method of claim 1, using sludge and microplastics as raw materials.

3. A method for applying the iron-carbon micro-electrolysis filler material using sludge and microplastics as raw materials as described in claim 2, characterized in that, Includes the following steps: Step 1: Pre-treat industrial wastewater containing heavy metal Sb from dyeing and printing wastewater through microfiltration. Step 2: Add the prepared iron-carbon micro-electrolysis filler into the simulated wastewater; Step 3: Aerate the simulated wastewater in the beaker to further improve the treatment efficiency of the packing material.

4. The application method of the iron-carbon micro-electrolysis filler material using sludge and microplastics as raw materials as described in claim 3, characterized in that, In step 1, the concentration of heavy metal Sb is 500~4000 μg / L; the pH range of the simulated wastewater is 3~11; and the treatment time is 1.5h.

5. The application method of the iron-carbon micro-electrolysis filler material using sludge and microplastics as raw materials as described in claim 3, characterized in that, In step 2, the dosage of iron-carbon micro-electrolysis filler is 1~5 g / L.

6. The application method of the iron-carbon micro-electrolysis filler material using sludge and microplastics as raw materials as described in claim 3, characterized in that, In step 3, the device for aeration treatment at a low concentration of 0-2 mg / L is an adjustable oxygenation pump.

7. The application method of the iron-carbon micro-electrolysis filler material using sludge and microplastics as raw materials as described in claim 3, characterized in that, After the application is completed, the iron-carbon micro-electrolysis filler is rinsed with tap water and then recycled.

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