Process for preparing powder anhydrous accelerating agent by organic waste sulfuric acid and aluminum ash collaborative resource treatment

Abstract

The present application belongs to the field of industrial environmental protection process, and proposes a process for preparing powder anhydrous quick coagulant by synergistically processing organic waste sulfuric acid and aluminum ash, which comprises the following steps: aluminum ash extraction, denitrification and desalination, waste sulfuric acid acidity adjustment, high-temperature calcination and reaction, calcined waste gas treatment, and preparation of anhydrous quick coagulant; under high-temperature conditions, sulfuric acid and metal oxides in aluminum ash generate composite sulfates, and if the waste sulfuric acid contains organic matter, the organic matter is first burned to remove the organic matter; the fluorine in the aluminum ash exists in the form of fluoride salt to obtain clinker; the clinker is added with magnesium sulfate, sodium fluorosilicate and the like, and uniformly mixed in a mixer to obtain powder anhydrous quick coagulant. The present application is rationally designed and can realize synergistic disposal, resource utilization, energy recovery, environmental friendliness, process stability and product diversification, and is suitable for large-scale promotion.

Description

Technical Field

[0001] This invention belongs to the field of industrial environmental protection technology, and in particular relates to a process for the synergistic resource treatment of organic waste sulfuric acid and aluminum ash to prepare anhydrous powdered quick-setting agent. Background Technology

[0002] Currently, waste sulfuric acid is typically classified into high-concentration and low-concentration waste sulfuric acid based on its concentration; it can also be classified into high-organic-content and low-organic-content waste sulfuric acid based on its organic matter content. Aluminum ash is a solid waste residue generated during the smelting and processing of aluminum. Depending on its source and aluminum content, it is classified into primary and secondary aluminum ash. Aluminum ash is classified as hazardous waste due to its high content of active substances and total aluminum, and its high value in terms of heat energy and aluminum element. Accelerators are classified into alkaline and acidic accelerators based on their acidity / alkalinity; and into anhydrous, liquid, and hydrated accelerators based on their water content. Generally, in industrial practice, waste sulfuric acid and aluminum ash are treated separately, but there are varying degrees of problems with the separate treatment process.

[0003] The disposal of aluminum ash presents challenges, including its hazardous waste status, resource waste, safety risks, environmental risks, insignificant volume reduction, and low aluminum recovery rates. Currently used pretreatment methods such as aluminum extraction, acid dissolution, alkali dissolution, and calcination all suffer from insignificant volume reduction. In industrial production, issues remain regarding the safe control of hydrogen and ammonia, large-scale production, and economic benefits. In industrial implementation, the main issues are: ① The safe handling of hazardous substances (hydrogen, fluorine, chlorine, nitrogen, salts, etc.), especially the risk of hydrogen deflagration and explosion, which places high demands on equipment and reaction rates. The safe and effective utilization of these elements in industrial applications hinders large-scale production. ② Low-value-added products: mainstream processes such as the preparation of aluminum sulfate, polyaluminum chloride, cement additives, and inert aluminum materials (acids) The market capacity for aluminum ash is small, resulting in low profit margins. The utilization rate of alumina in aluminum ash is only about 40%, and the aluminum ash residue after treatment accounts for 50% of the total original aluminum ash, which is far from meeting the demand for resource reduction. Moreover, the added value of the residue is low, which is also a major factor restricting large-scale production. High energy consumption: Although there are combinations of alkali sintering and Bayer process for aluminum ash in China, the energy consumption is high, the process is complex, the process is long, the investment is large, and the maintenance cost is high. The remaining residue is still about 30%. In practice, the products obtained by sintering (aluminum hydroxide and alumina) also face low economic benefits and fierce market competition.

[0004] The disposal of waste sulfuric acid presents several challenges, including high treatment costs, high equipment investment, severe equipment corrosion, difficulty in secondary treatment, significant safety hazards, and high energy consumption. Commonly used processes for treating waste sulfuric acid with high organic content include high-temperature pyrolysis, neutralization, and combined oxidation-adsorption methods. The main problems in industrial applications are: ① For waste sulfuric acid with high organic content, independent high-temperature pyrolysis at 1100℃ is required, resulting in high energy consumption, high investment in sulfuric acid recovery equipment, and severe corrosion; ② Co-pyrolysis technologies, such as those used in gypsum-based sulfuric acid production and cement co-production, require temperatures above 1350℃, yielding calcium sulfate with low added value, leading to a market supply far exceeding demand, poor economic benefits, and difficulty in sustained mass production; ③ Concentrated regeneration of waste sulfuric acid requires concentration, membrane separation, decolorization, and other desalination and purification processes, placing high demands on equipment corrosion resistance. Difficulties in sulfuric acid decolorization and organic matter removal often result in the quality of subsequently prepared sulfate products failing to meet market demands, hindering sustained mass production; ④ Carbonization reduction technology is suitable for waste sulfuric acid generated from petrochemicals, but its application is limited and cannot meet the diverse disposal needs of industrial waste sulfuric acid.

[0005] Regarding accelerators, the following pain points exist in their actual use: ① The competitiveness of accelerators currently lies in their water content, which restricts transportation distance; ② Alkaline accelerators suffer from severe strength reduction, alkali-aggregate reaction risks, and corrosion of spraying equipment pipelines; ③ The accelerator market currently favors alkali-free accelerators, which generally use aluminum sulfate as the main component. The aluminum sulfate solid obtained by evaporation contains 48% water of crystallization, still resulting in high water content; ④ Difficulty in obtaining anhydrous aluminum sulfate: The conventional process for preparing anhydrous aluminum sulfate involves first obtaining an aluminum sulfate solution, then evaporating and crystallizing it. Due to the strong water-shrinking property of aluminum sulfate, solid aluminum sulfate needs a temperature above 300 degrees Celsius to become a fluid above 120 degrees Celsius, and complete dehydration is difficult, making it difficult to achieve with equipment and resulting in high industrial energy consumption; ⑤ Energy waste: Anhydrous accelerators consume a lot of energy during production, but an aqueous solution still needs to be added during use. Although this saves on transportation costs, the overall cost is still relatively high, and from the perspective of the entire production chain, energy is wasted.

[0006] Existing patent CN113441510A discloses a waste-to-waste landfill method for treating aluminum ash with industrial waste acid. This method proposes to treat industrial solid and liquid waste by disposing of waste sulfuric acid and aluminum ash through a waste-to-waste approach, directly producing ammonium sulfate and aluminum ash slag. This patent fixes the harmful nitrogen with sulfuric acid, but it does not address the treatment of harmful elements (fluorine, chlorine, hydrogen, salts, etc.) in aluminum ash and harmful substances (organic matter, salts, fluorine, etc.) in waste sulfuric acid. In particular, it raises safety concerns regarding hydrogen generation and environmental issues related to odors. Furthermore, this process does not utilize the useful components in aluminum ash, relies on landfilling, and fails to address the utilization of aluminum ash resource value. This results in poor economic benefits, unsustainable industrial operation, and difficulty in achieving reduction, resource recovery, sustainability, and feasibility in industrial implementation.

[0007] Existing patent CN118005061A discloses a method for preparing highly active polyaluminum sulfate flocculant using secondary aluminum ash. The method involves mixing phosphoric acid and sulfuric acid solutions, adding them to the secondary aluminum ash, stirring, drying, and calcining at 300-600°C. The resulting calcined activated material is then mixed with water, stirred, and subjected to solid-liquid separation. Sodium hydroxide solution is added to the liquid to adjust the pH to 3-6, followed by low-temperature plasma irradiation and drying to obtain the highly active polyaluminum sulfate flocculant. However, this process does not mention methods for treating harmful substances such as nitrogen, salts, and fluorine in the aluminum ash, nor does it address the safety risks associated with hydrogen generation during mixing. The product is polyaluminum sulfate, and the patent does not explain the role or fate of phosphoric acid. The slurry has a high water content, resulting in high energy consumption. The subsequent dissolution process uses sodium hydroxide to adjust the pH to 3-6, but the impact of pH on product quality is not explained. This process does not consider the conversion of nitrogen in aluminum nitride, a harmful substance in the aluminum ash, into ammonium ions. The ammonia nitrogen content directly affects the product quality of the aluminum sulfate flocculant, and ammonia nitrogen content is a key control indicator. Furthermore, the aluminum ash contains approximately 10% salt, which also affects product quality.

[0008] Existing patent CN114477827A discloses a method for producing cement accelerators through the comprehensive treatment of secondary aluminum ash. This method involves mixing secondary aluminum ash, a calcium source, and alkaline additives to obtain a mixed raw material. This mixture is then calcined at 950-1200℃ and cooled to obtain the cement accelerator. The secondary aluminum ash contains 10% chloride, and the accelerator requires a chloride content of <0.1%. Chloride is highly corrosive to steel, but the patent does not address this issue. Under alkaline conditions, aluminum ash and the calcium source undergo side reactions, sintering into calcium aluminate powder and agglomerates. Sodium aluminate is responsible for the accelerator's setting effect, thus affecting the alumina extraction rate and the accelerator's effectiveness. Currently, the market demand for alkali-free accelerators is shifting from traditional alkaline accelerators to cost-effective alkali-free accelerators, but market demand is small. High alkali content easily leads to concrete expansion and damage, generating corrosive dust that threatens the health of construction workers and may pollute the environment during production. Liquid accelerators, due to their inherent properties, have higher transportation costs, limiting their market reach.

[0009] The above methods all propose recovering alumina from aluminum ash using acid and alkali methods. However, none of them consider how to comprehensively utilize the ammonia and hydrogen generated during the process, nor do they address the final safe treatment methods for chlorides and fluorides. As a result, the products obtained are of poor quality, have high costs, and are limited in market application scenarios. Summary of the Invention

[0010] To address the technical problems existing in the aforementioned ZZ, this invention proposes a reasonable, environmentally friendly, stable, and diversified process for the co-processing of organic waste sulfuric acid and aluminum ash to prepare anhydrous powdered quick-setting agent.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows: the present invention provides a process for preparing anhydrous powdered quick-setting agent through the synergistic resource treatment of organic waste sulfuric acid and aluminum ash, comprising the following specific steps:

[0012] S1. Aluminum extraction from aluminum ash: Secondary aluminum ash is screened, separated, and air-classified to obtain high-content aluminum ash; the high-content aluminum ash is ball-milled to obtain aluminum balls or aluminum flakes, and fine aluminum ash is separated out. The aluminum content of the fine aluminum ash is <1%, which can reduce the amount of hydrogen generated from the source and increase the feeding speed by 4-5 times.

[0013] S2, Denitrification and Desalination: The aluminum ash treated in step S1 is hydrolyzed in a hydrolysis tank to denitrify and desalinate, and then washed to obtain harmless aluminum ash.

[0014] S3. Acidity adjustment of waste sulfuric acid: If the concentration of organic waste sulfuric acid is less than 70%, concentrated waste sulfuric acid or industrial sulfuric acid with a concentration >98% should be used to adjust the acidity of the low-concentration waste sulfuric acid to ensure that the concentration of waste sulfuric acid participating in the reaction is greater than 70%.

[0015] S4. High-Temperature Calcination and Reaction: Harmless aluminum ash and sulfuric acid are sprayed into a rotary kiln, and the calcination temperature is 600-700℃. Under high temperature, waste sulfuric acid reacts with alumina in the harmless aluminum ash to produce aluminum sulfate. Metal oxides other than alumina in the harmless aluminum ash react with sulfuric acid to produce corresponding sulfates, including magnesium sulfate and ferric sulfate. Fluorine and aluminum in the harmless aluminum ash react at high temperature to produce fluoride salts. The calcined clinker is then cooled in a cooling cylinder.

[0016] S5. Calcination waste gas treatment: The waste gas generated in step S4 is input into the waste gas system and converted into salt products through multi-stage absorption and adsorption treatment. The salt products include sulfates and sulfites.

[0017] S6. Preparation of anhydrous quick-setting agent: The clinker obtained in step S4, which includes aluminum sulfate, magnesium sulfate, ferric sulfate and fluoride, is mixed with additive A according to the proportion of each component. Additive A includes at least sodium fluorosilicate and magnesium sulfate. The clinker and additive A are mixed in a mixer to obtain anhydrous quick-setting agent.

[0018] Preferably, before step S3, the aluminum ash is pretreated, and then the harmless aluminum ash and waste sulfuric acid can be reacted quickly to generate aluminum sulfate; the waste sulfuric acid contains organic matter, and the organic matter is fully burned in the rotary kiln. The combustion process releases a large amount of reaction heat, which can realize the energy conversion of organic matter and also ensure the anhydrous form of the accelerator.

[0019] Preferably, in step S3, the organic waste sulfuric acid is pretreated by using an adsorbent solid residue to remove some of the organic matter contained in the organic waste sulfuric acid.

[0020] Preferably, the adsorbable organic solid slag is pressed into a cake-like structure using a press to serve as an organic adsorbent component.

[0021] Preferably, the organic adsorbent assembly includes multiple adsorption cam rings arranged in a nested pattern, the inner hole of the adsorption cam ring is an eccentric hole, the bottom of the outer wall of the adsorption cam ring is provided with an annular groove, and the bottom of the inner hole of the adsorption cam ring is provided with a positioning ring platform.

[0022] Preferably, each of the adsorption cam rings includes two symmetrically arranged semi-rings, and each semi-ring has two lifting blind holes near its distal end, which are symmetrically arranged on the upper and lower surfaces of the semi-rings.

[0023] Preferably, the upper and lower surfaces of the outermost adsorption cam ring are provided with a plurality of conical holes arranged in a circular array, and the conical holes are used to install positioning rollers, the positioning rollers being a double conical structure.

[0024] Preferably, the bottom of the organic adsorbent assembly is provided with a support member, which is a groove-shaped structure with the opening facing downwards. The surface of the support member is provided with a plurality of filter holes, and the interior of the support member is provided with a plurality of radially distributed reinforcing ribs.

[0025] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0026] This invention provides a process for the co-processing of organic waste sulfuric acid and aluminum ash to prepare anhydrous powdered quick-setting agent. This process solves the problems associated with the separate disposal of waste sulfuric acid and aluminum ash. Through the co-processing of waste sulfuric acid and aluminum ash, the waste is transformed into a marketable concrete admixture product. Simultaneously, it significantly improves the recovery of organic matter from waste sulfuric acid, achieving more efficient volume reduction and maximizing zero emissions, resulting in significant economic and environmental benefits. This invention is rationally designed and enables co-processing, resource utilization, energy recovery, environmental friendliness, process stability, high economic efficiency, and product diversification, making it suitable for large-scale promotion. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 The process diagrams for the co-processing of organic waste sulfuric acid and aluminum ash to prepare powdered anhydrous rapid-setting agent provided in Examples 1-5 are shown.

[0029] Figure 2 A perspective view of the organic adsorbent assembly provided by the present invention;

[0030] Figure 3 A perspective view of the organic adsorbent assembly provided by the present invention from another direction;

[0031] Figure 4 A perspective view of the organic adsorbent assembly and support provided by the present invention;

[0032] Figure 5 A top view of the organic adsorbent assembly and support provided by the present invention;

[0033] Figure 6 A bottom view of the organic adsorbent assembly and support provided by the present invention;

[0034] In the above figures: 1. Organic adsorbent assembly; 2. Adsorption cam ring; 21. Eccentric hole; 22. Annular settling tank; 23. Positioning ring platform; 24. Semi-ring; 25. Lifting blind hole; 26. Conical hole; 3. Positioning roller; 4. Support component; 41. Filter hole; 42. Reinforcing rib plate. Detailed Implementation

[0035] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. For ease of description, the terms "upper," "lower," "left," and "right" appearing below only indicate that they correspond to the upper, lower, left, and right directions in the accompanying drawings and do not limit the structure.

[0036] Numerous specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways than those described herein, and therefore the invention is not limited to the specific embodiments disclosed in the following specification.

[0037] The aluminum ash used in the following examples is secondary aluminum ash, which comes from the secondary aluminum ash produced by the alloy aluminum casting process. Its elemental composition is 70% Al2O3 (elemental aluminum, aluminum nitride, aluminum carbide and other aluminum compounds, converted to alumina), 3.5% SiO2, 0.5% FeOx, 4.8% Mg, 0.5% Ca, 6% salt; 5.28% nitrogen; 1.6% F; 0.6% carbon powder, etc. The waste sulfuric acid comes from hazardous solid waste sulfuric acid generated by chemical processes such as alkylated sulfuric acid, sulfonated sulfuric acid, dehydrated sulfuric acid, and catalyst sulfuric acid. Example 1

[0038] like Figure 1 As shown, the present invention provides a process for preparing anhydrous powdered rapid-setting agent through the co-processing of organic waste sulfuric acid and aluminum ash, comprising the following specific steps:

[0039] S1. Aluminum extraction from aluminum ash: 71% alumina is screened, separated and air-classified to obtain high-content aluminum ash; the high-content aluminum ash is ball-milled to obtain aluminum balls or aluminum flakes, and fine aluminum ash is separated out. The aluminum content of the fine aluminum ash is <1%, which can reduce the amount of hydrogen generated from the source and increase the feeding speed by 4-5 times.

[0040] S2. Denitrification and Desalination: The fine aluminum ash obtained from S1 is hydrolyzed with water at a liquid-to-solid ratio of 3:1 in a hydrolysis tank. The temperature is controlled at 95℃-100℃, and aeration is added simultaneously. The liquid level is monitored during the process to prevent overflow. The reaction time is 8 hours. The ammonia gas released during the process is absorbed by a three-stage sulfuric acid process to prepare ammonium sulfate. The hydrogen gas released during the process is burned in a high-temperature rotary kiln. The slurry after the reaction is separated into solid and liquid components by a filter press. The filter cake is then filtered, washed, and air-dried to obtain a nitrogen content of <0.15%, a chlorine content of <0.1%, and an aluminum content of <0.1%, thus obtaining denitrified and desalinated harmless aluminum ash.

[0041] S3. Acidity adjustment of waste sulfuric acid: If the organic waste sulfuric acid concentration is below 70%, concentrated waste sulfuric acid (≥85%) or industrial sulfuric acid (concentration >98%) is used to adjust the acidity of the low-concentration waste sulfuric acid to ensure that the concentration of waste sulfuric acid participating in the reaction is greater than 70%.

[0042] S4. High-Temperature Calcination and Reaction: Prepared waste sulfuric acid and harmless aluminum ash are sprayed into a rotary kiln at a mass ratio of 2.2:1 (sulfuric acid equivalent to 98%). The calcination temperature is 600-700℃ for 30 minutes. During the process of reaching the high temperature, the metal oxides in the sulfuric acid and harmless aluminum ash react rapidly to generate sulfates such as aluminum sulfate, magnesium sulfate, ferric sulfate, and calcium sulfate, as well as fluorides. In the rotary kiln, the organic matter in the waste sulfuric acid can be fully combusted, achieving the removal of organic matter. The combustion process releases a large amount of heat of reaction, enabling the energy conversion of organic matter and also helping to ensure the anhydrous form of the accelerator. The calcined clinker is cooled in a cooling cylinder using air cooling.

[0043] The clinker obtained from step S4 has the following composition: 72.7% aluminum sulfate, 8.3% magnesium sulfate, 0.35% ferric sulfate, 3.88% sodium fluoride, and 1.5% other sulfates; chloride content is 0.01%; and 12.4% insoluble slag is used as filler, with corundum-grade alumina as its main component.

[0044] S5. Calcination exhaust gas treatment: The exhaust gas generated in step S4 is input into the exhaust gas system. The residual aluminum nitride is converted into nitrogen at high temperature. The exhaust gas is converted into salt products through multi-stage absorption and adsorption treatment. The salt products include sulfate and sulfite. The multi-stage absorption and adsorption treatment includes cyclone dust removal + pulse dust removal + water spray + adsorption treatment. The exhaust gas meets the emission standards.

[0045] Accelerator effect test on clinker: initial setting time 5′20s, final setting time 15′31s, compressive strength at 1 day 5.0, compressive strength at 28 days 61. Example 2

[0046] The modified condition in Example 2 is that the solid-liquid ratio of waste acid and harmless aluminum ash in step S4 is 2.3:1. Apart from this, the rest of the process is the same as in Example 1.

[0047] The clinker composition obtained from step S4 in this embodiment is as follows: 78.2% aluminum sulfate, 8.2% magnesium sulfate, 0.37% ferric sulfate, 3.9% sodium fluoride, and 2% other sulfates; chloride content is 0.01%; 7% insoluble slag is used as a filler, and its main component is corundum-grade alumina.

[0048] The effect of the accelerator on clinker was tested: initial setting time 4′34s, final setting time 12′28s, compressive strength at 1 day 7.5, and compressive strength at 28 days 83; the obtained powdered anhydrous accelerator was qualified. Example 3

[0049] The modified condition in Example 3 is that the solid-liquid ratio of waste acid and harmless aluminum ash in step S4 is 2.35:1. Apart from this, the rest of the process is the same as in Example 1.

[0050] The clinker composition obtained in this embodiment is as follows: 82.4% aluminum sulfate, 7.6% magnesium sulfate, 0.4% ferric sulfate, 3.6% sodium fluoride, and 2% other sulfates; chloride content is 0.01%; 5% insoluble slag is used as a filler, the main component of which is corundum-grade alumina.

[0051] The effect of the accelerator on clinker was tested: initial setting time 3′04s, final setting time 7′28s, compressive strength at 1 day 9.2, and compressive strength at 28 days 88; the obtained powdered anhydrous accelerator was qualified. Example 4

[0052] The modified condition in Example 4 is that the solid-liquid ratio of waste acid and harmless aluminum ash in step S4 is 2.4:1. Apart from this, the rest of the process is the same as in Example 1.

[0053] The clinker composition is as follows: 83.1% aluminum sulfate, 7.5% magnesium sulfate, 0.4% ferric sulfate, 2.9% sodium fluoride, and 2% other sulfates; chloride content is 0.01%; 4% insoluble slag is used as filler, and its main component is corundum-grade alumina.

[0054] Add step S6 to prepare an anhydrous quick-setting agent: condition the clinker, add additive A according to the proportion of each component, such as adding 2% sodium fluorosilicate, adjusting the magnesium sulfate content to 13%, adding 1.5% fine fumed silica powder, and mix evenly to obtain an anhydrous quick-setting agent.

[0055] Tests on the effect of the accelerator: initial setting time 2′11s, final setting time 5′58s, compressive strength at 1 day 11.7, compressive strength at 28 days 92; the obtained powdered anhydrous accelerator is of first grade. Example 5

[0056] Example 5 changes the conditions so that the solid-liquid ratio of waste acid and harmless aluminum ash in step S4 is 2.45:1. Otherwise, the process is the same as in Example 1.

[0057] The clinker composition obtained in this embodiment is as follows: 83.5% aluminum sulfate, 7.0% magnesium sulfate, 0.35% ferric sulfate, 2.5% sodium fluoride, and 2% other sulfates; chloride content is 0.01%; and 4.1% insoluble slag is used as a filler, the main component of which is corundum-grade alumina.

[0058] Add step S6 to prepare an anhydrous quick-setting agent: condition the clinker, add additive A according to the proportion of each component, such as adding 2% sodium fluorosilicate, adjusting the magnesium sulfate content to 15%, adding 1.5% fine fumed silica powder, and mix evenly to obtain an anhydrous quick-setting agent.

[0059] Tests on the effect of the accelerator: initial setting time 2′04s, final setting time 4′28s, compressive strength at 1 day 12, compressive strength at 28 days 93; the obtained powdered anhydrous accelerator is of first grade.

[0060] Comparative tests were conducted on the alkali-free powdered rapid-setting agents prepared in Examples 1 to 5. A benchmark was selected. Silicate cement, mountains and rivers of Dongyue Testing of ordinary Portland cement for engineering applications. The alkali-free powdered accelerator was tested for its setting time and mortar strength according to GB / T35159-2017 "Accelerators for Shotcrete". The dosage of the accelerator was calculated as a percentage of the cement weight. The test results are shown in the table below:

[0061] Furthermore, in step S3, the organic waste sulfuric acid is pretreated by using an adsorbent solid residue to remove some of the organic matter contained in the organic waste sulfuric acid.

[0062] Regarding the adsorbable organic solid slag, this invention preferentially utilizes solid slag generated from the treatment of alkylated waste sulfuric acid. Since alkylated waste sulfuric acid contains 20% olefin polymers, it can be transformed into carbonized polymers through a polymerization addition reaction in related processes. The adsorbable organic solid slag is a carbonized polymer, whose main components include high-molecular-weight hydrocarbons. Its structural basis gives it adsorption properties different from general adsorbents, exhibiting a synergistic effect of physical and chemical adsorption. Physical adsorption provides initial binding, while chemical adsorption enhances stability. More specifically, in terms of physical adsorption, the polymer decomposition during the carbonization process generates numerous pores with a high specific surface area, providing ample adsorption sites. Furthermore, the hierarchical pore distribution and the mesoporous structure of the carbonized polymer nanofibers accelerate the diffusion of organic matter in water to the adsorption sites. In terms of chemical adsorption, oxygen-containing and nitrogen-containing functional groups can be introduced during carbonization, enhancing the affinity for polar molecules through chemical adsorption. Therefore, the organic-adsorbing solid slag, which is a byproduct of other processes, can be effectively utilized in this process, demonstrating good usability. Moreover, it can not only be used in this process but also as an adsorption product for use in other process lines in the chemical industry.

[0063] In order to improve the adsorption performance of the organic adsorbent component 1 in this invention, the solid slag provided by this invention is pressed into a cake-like structure by a press.

[0064] Furthermore, the provided organic adsorbent assembly 1 includes multiple adsorption cam rings 2 arranged in a nested configuration. The inner hole of each adsorption cam ring 2 is an eccentric hole 21, and the bottom of the outer wall of each adsorption cam ring 2 is provided with an annular groove 22. The bottom of the inner hole of each adsorption cam ring 2 is provided with a positioning ring platform 23. The outer ring of each adsorption cam ring 2 is perfectly circular, and its inner ring is an eccentric hole 21. A smaller adsorption cam ring 2 is installed in the eccentric hole 21. The interlocking annular groove 22 and positioning ring platform 23 provide mutual support. Simultaneously, the bottom of the largest adsorption cam ring 2 may not have an annular groove 22, while the bottom of the smallest adsorption cam ring 2 may not have a positioning ring platform 23, and the inner side of the smallest adsorption cam ring 2 remains hollow. This invention compresses solid slag into a porous, cake-like structure. This facilitates installation into adsorption treatment equipment and, compared to bulk solid slag, improves the uniformity of waste sulfuric acid treatment per unit cross-section by the organic adsorbent assembly. Furthermore, the use of detachable adsorption cam rings 2 allows for targeted replacement, enhancing the overall utilization rate of the organic adsorbent assembly 1. The sequentially assembled organic adsorbent assemblies 1, besides increasing the adsorption working surface to improve the treatment efficiency of organic matter carried by waste sulfuric acid, also utilize eccentric holes 21 as mounting holes in each layer. By changing the relative angle of adjacent organic adsorbent assemblies 1, structural support can be provided for the layer above without affecting the rotation adjustment of other adsorption cam rings 2 in the same layer. This effectively ensures the structural strength and stability of the entire organic adsorbent assembly 1 within the adsorption equipment, thereby facilitating better adsorption of organic matter from other high-organic-content waste sulfuric acid.

[0065] To facilitate the assembly of the adsorption cam ring 2, the adsorption cam ring 2 provided by this invention includes two symmetrically arranged semi-rings 24. Each semi-ring 24 has two lifting blind holes 25 near its distal end, symmetrically arranged on the upper and lower surfaces of the semi-ring 24. This allows a pair of semi-rings 24 to be assembled into the adsorption equipment sequentially. Furthermore, the arc-shaped inner wall of the eccentric hole 21 allows the semi-rings 24 to pass through a pipe opening smaller than its actual diameter, satisfying the assembly requirements of adsorption cam rings 2 of different diameters without causing severe impact that could affect their use. The lifting blind holes 25 on the semi-rings 24 can serve as lifting nodes, allowing lifting equipment in the workshop or factory area to clamp the lifting fixtures onto the two blind holes 25, facilitating efficient installation of the adsorption cam ring 2 into the adsorption tank / adsorption tower. Moreover, designing the blind holes 25 at the distal end of the eccentric hole 21, i.e., at a position with a larger solid surface, helps ensure the quality of the adsorption cam ring 2 before and after lifting.

[0066] To improve the overall stability of the organic adsorbent assembly 1, this invention provides multiple conical holes 26 arranged in a circular array on the upper and lower surfaces of the outermost adsorption cam ring 2. Positioning rollers 27, which have a double-conical structure, are installed in these conical holes 26 to facilitate quick insertion and positioning with the upper and lower adsorption cam rings 2. By using the positioning rollers 27 and the conical holes 26 in conjunction, the adjacent adsorption cam rings 2 can be positioned. This allows for controlled adjustment of the positions of the eccentric holes 21 in the upper and lower layers during manual assembly of the adsorption cam rings 2, ensuring mutual support between adjacent layers. Furthermore, the smallest eccentric hole 21 can accommodate a portion of the treated liquid, and appropriately adjusting the resistance of waste sulfuric acid passing through the surfaces of different layers of adsorption cam rings 2 helps improve adsorption efficiency.

[0067] To improve the structural stability of the organic adsorbent assembly in the adsorption tank / adsorption tower, the organic adsorbent assembly provided by the present invention has a support member 4 at its bottom. The support member 4 has a downward-facing groove-shaped structure, and its surface is provided with a plurality of filter holes 41. The interior of the support member 4 is provided with a plurality of radially distributed reinforcing ribs 42. The support member 4 with the reinforcing ribs 42 structure can obtain high structural strength, its surface filter holes 41 can accommodate the filtrate, and its groove edge can be used to clamp onto the inner shoulder of the adsorption tank / adsorption tower. The support member 4 constitutes the support for the organic adsorbent assembly 1, which helps to ensure the working performance of the organic adsorbent assembly 1.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A process for preparing powder anhydrous accelerating agent by synergistically processing organic waste sulfuric acid and aluminum ash, characterized in that, The method comprises the following specific steps: S1, aluminum extraction from aluminum ash: secondary aluminum ash is screened, separated and air separated to obtain high-content aluminum ash; the high-content aluminum ash is ball milled to obtain aluminum balls or aluminum sheets, and fine aluminum ash with an aluminum content of less than 1% is separated out, which can reduce the amount of hydrogen generated at the source and increase the feeding speed by 4-5 times; S2, denitrification and desalination: the aluminum ash treated in step S1 is hydrolyzed in a hydrolysis tank to remove nitrogen and salt, and harmless aluminum ash is obtained after washing; S3, acidity adjustment of waste sulfuric acid: if the concentration of organic waste sulfuric acid is less than 70%, concentrated waste sulfuric acid or industrial sulfuric acid with a concentration of more than 98% is used to adjust the acidity of the low-concentration waste sulfuric acid, so as to ensure that the concentration of the waste sulfuric acid participating in the reaction is greater than 70%; S4, high-temperature calcination and reaction: the harmless aluminum ash and waste sulfuric acid are sprayed into a rotary kiln, and the calcination temperature is 600-700°C; under high temperature, the waste sulfuric acid reacts with aluminum oxide in the harmless aluminum ash to generate aluminum sulfate, and the metal oxides other than aluminum oxide in the harmless aluminum ash react with sulfuric acid to generate corresponding sulfates, including magnesium sulfate and iron sulfate; fluorine and aluminum in the harmless aluminum ash react at high temperature to generate fluoride; the calcined clinker is cooled in a cooling cylinder; S5, treatment of calcination waste gas: the waste gas generated in step S4 is input into a waste gas system and converted into salt products including sulfates and sulfites through multi-stage absorption and adsorption treatment; S6, preparation of anhydrous accelerator: the clinker obtained in step S4, including aluminum sulfate, magnesium sulfate, iron sulfate and fluoride, is supplemented with an additive A according to the proportion of each component, the additive A at least including sodium fluorosilicate and magnesium sulfate, and the clinker and the additive A are mixed in a mixer to obtain an anhydrous accelerator.

2. The process for preparing powder anhydrous accelerating agent by synergistic resource treatment of organic waste sulfuric acid and aluminum ash according to claim 1, characterized in that, Before step S3, the aluminum ash is pretreated, and then the harmless aluminum ash and the waste sulfuric acid can quickly react to generate aluminum sulfate; if the waste sulfuric acid contains organic matter, the organic matter is fully combusted in the rotary kiln, a large amount of reaction heat is released in the combustion process, the energy of the organic matter can be realized, and the anhydrous of the accelerator is ensured.

3. The process for preparing powder anhydrous accelerating agent from organic waste sulfuric acid and aluminum ash according to claim 1, characterized in that, In step S3, the organic waste sulfuric acid is pretreated, and the pretreatment method is to use an organic matter adsorbable solid residue to remove part of the organic matter contained in the organic waste sulfuric acid.

4. The process for preparing powder anhydrous accelerating agent from organic waste sulfuric acid and aluminum ash according to claim 3, characterized in that, The organic matter adsorbable solid residue is pressed into a cake structure by a press as an organic matter adsorbent assembly.

5. The process for preparing powder anhydrous accelerating agent from organic waste sulfuric acid and aluminum ash synergistic resource treatment according to claim 4, characterized in that, The organic matter adsorbent assembly comprises a plurality of adsorption cam rings arranged in an inner-outer nested manner, the inner hole of the adsorption cam ring is an eccentric hole, the outer wall bottom of the adsorption cam ring is provided with an annular sink, and the inner hole bottom of the adsorption cam ring is provided with a positioning ring table.

6. The process for preparing powder anhydrous accelerating agent from organic waste sulfuric acid and aluminum ash synergistic resource treatment according to claim 5, characterized in that, Each adsorption cam ring comprises two symmetrically arranged half rings, two lifting blind holes are arranged on the upper surface and the lower surface of the half ring near the far end thereof, and the lifting blind holes are symmetrically arranged on the upper surface and the lower surface of the half ring.

7. The process for preparing powder anhydrous accelerating agent from organic waste sulfuric acid and aluminum ash synergistic resource treatment according to claim 6, characterized in that, The upper surface and the lower surface of the outermost adsorption cam ring are provided with a plurality of circular array distributed conical holes, the conical holes are used to install positioning rollers, and the positioning rollers are double-cone structures.

8. The process for preparing powder anhydrous accelerating agent from organic waste sulfuric acid and aluminum ash synergistic resource treatment according to claim 7, characterized in that, The bottom of the organic adsorbent assembly is provided with a support member, which is a groove-shaped structure with the opening facing downward. The surface of the support member is provided with a number of filter holes, and the interior of the support member is provided with a number of radially distributed reinforcing ribs.

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