Preparation of organic slurry using waste activated carbon and waste tires and method thereof

Abstract

The application discloses a kind of preparation organic slurry using waste activated carbon and waste tire and its preparation method, the preparation method, comprising: dry waste activated carbon powder, dry waste tire powder, dispersing agent and water are stirred uniformly, and the mixture is obtained by standing;Solid mixture and combustion improver are added into water and stirred uniformly, and organic slurry is obtained by standing.The preparation method can efficiently prepare waste activated carbon and waste tire into organic slurry, and the prepared organic slurry has higher slurry forming property and calorific value.

Description

Technical Field

[0001] This invention relates to organic slurry preparation technology, specifically to a method for preparing a total solid waste stabilized organic slurry using waste activated carbon and waste tires. Background Technology

[0002] Coal-water slurry, a new type of efficient and clean coal-based fluid fuel proposed in the United States in the 1950s and initiated in my country in the late 1970s, is used to replace oil with coal. It simultaneously produces syngas through anoxic combustion, which can be used as a raw material for chemical products. Coal-water slurry is a solid-liquid dispersion mixture consisting of no less than 50-70% pulverized coal, 30-50% water, and 0.5-1% chemical additives. Coal-water slurry has advantages such as low pollution, high efficiency, and pipeline transportability. It is also one of the key technologies prioritized for clean coal development in the coal industry. Coal-water slurry alters the form of coal, converting lumpy solid coal into liquid fuel. Atomized into fine particles through nozzles, the atomized coal-water slurry can fully contact oxygen, resulting in a higher combustion rate and efficiency than traditional direct coal combustion. Furthermore, the exhaust gases, such as flue gas, soot, and sulfur dioxide, produced by coal-water slurry boilers comply with the "Emission Standard of Air Pollutants for Boilers" (GB13271-2014), meeting my country's environmental protection requirements.

[0003] The high efficiency and cleanliness of coal-water slurry technology make it suitable for treating both solid and hazardous waste. Carbon-rich solid wastes with calorific value, such as spent activated carbon and waste tires, can partially replace coal after being crushed, screened, and dispersed in the coal-water slurry system. Simultaneously, high-concentration wastewater, waste organic solvents, waste oil, and emulsifiers dispersed in the coal-water slurry system can act as volatiles in the coal, assisting in the combustion / gasification reaction. Therefore, the co-treatment of solid and liquid waste using coal-water slurry technology not only reduces coal consumption and saves energy but also treats both solid and hazardous waste, demonstrating significant environmental and economic benefits.

[0004] Activated carbon is a porous adsorbent material with important applications in water treatment, gas purification, and many other fields. However, after reaching saturation and regeneration failure, it transforms into spent activated carbon, which is listed as hazardous waste in my country (HW49) and poses a high environmental risk. Conventional treatment methods for spent activated carbon include incineration and landfill, making it difficult to achieve resource utilization. The main element of spent activated carbon is carbon, which exhibits a porous structure and can form a good solid-phase dispersion system with water, thus serving as a fixed carbon component in coal.

[0005] Waste tires are also a type of industrial solid waste produced in large quantities. They are mainly composed of rubber, carbon black, and additives, and have high volatile matter and fixed carbon content, making them an ideal substitute for coal. By co-producing waste tires and waste activated carbon into a slurry, the waste tires replace the fixed carbon and volatile matter in the coal, while the waste activated carbon replaces the fixed carbon in the coal. The resulting mixed organic slurry meets the combustion characteristics required by traditional coal-water slurry.

[0006] Since coal-water slurry is a solid-liquid two-phase suspension, its stability directly affects its transportation and storage costs. The main causes of instability in coal-water slurry are particle aggregation and sedimentation. Coal-water slurry is a thermodynamically unstable system, and the solid and liquid phases are prone to separation, making it difficult to maintain a uniform and stable morphology.

[0007] However, solid wastes such as waste tires and waste activated carbon differ greatly from coal in terms of density and hydrophilicity / hydrophobicity, making it difficult to directly utilize traditional pulping experience. Research on the pulping stability and flowability of organic pulps made from all solid wastes is almost nonexistent. Therefore, developing a method for preparing stable organic pulps based on waste activated carbon and waste tires is of great significance for the further development and application of waste activated carbon disposal, waste tire recycling, and organic pulping technology. Summary of the Invention

[0008] This invention provides a method for preparing organic slurry using waste activated carbon and waste tires. This method can efficiently prepare organic slurry from waste activated carbon and waste tires, and the prepared organic slurry has high stability and calorific value.

[0009] This invention provides a method for preparing organic slurry using waste activated carbon and waste tires, comprising:

[0010] (1) Mix dry waste activated carbon powder, dry waste tire powder, dispersant and water evenly and let stand to obtain a mixture;

[0011] (2) Add the combustion accelerator and water to the mixture obtained in step (1), stir evenly, and let stand to obtain an organic slurry. By adding the appropriate dispersant and combustion accelerator in a suitable order, the agglomeration of the powder is prevented, which is beneficial to the dispersion of waste activated carbon powder and waste tire powder.

[0012] Preferably, the weight ratio of the dried waste activated carbon powder, dried waste tire powder, dispersant, combustion accelerator, and water is:

[0013] 0-40 wt% of dried waste activated carbon powder;

[0014] 10-50 wt% of dry waste tire powder;

[0015] Water 48~49wt%;

[0016] Dispersant 0.5–2 wt%;

[0017] Combustion accelerator 0.5–2 wt%;

[0018] The sum of the weight ratios of the dry waste activated carbon powder, dry waste tire powder, dispersant, combustion accelerator, water, and unavoidable impurities is 100 wt%.

[0019] This invention provides an organic slurry with suitable stability by providing an appropriate amount of dried waste activated carbon powder, and an organic slurry with suitable calorific value by providing an appropriate amount of dried waste tire powder. Excessive dried waste activated carbon powder will result in excessively high volatile matter content in the prepared slurry, while excessive dried waste tire powder will reduce slurry stability and increase sulfur content, both of which are detrimental to the storage and combustion of the prepared organic slurry.

[0020] More preferably, the weight ratio of the dried waste activated carbon powder, dried waste tire powder, dispersant, combustion accelerator, and water is:

[0021] 20wt% of dried waste activated carbon powder;

[0022] 30wt% dry waste tire powder;

[0023] Water 48w%;

[0024] Dispersant 1.7 wt%;

[0025] Combustion accelerator 0.3 wt%.

[0026] Within this range, its stability is 4.6, its calorific value is 28.87 MJ / kg, and its viscosity is 735 mPa·s.

[0027] Meanwhile, through examples, it was found that the optimal ratio is 20-30% dry waste tire powder and 30-20% dry waste activated carbon powder.

[0028] Preferably, the dry waste activated carbon powder is any one of coal-based activated carbon, wood-based activated carbon, and coconut shell activated carbon.

[0029] Preferably, the dispersant is at least one of sodium methylene bisnaphthalene sulfonate, sodium lignosulfonate, and dodecyltrimethylammonium chloride.

[0030] Preferably, the combustion promoter is at least one of sodium petroleum sulfonate or sodium naphthenate.

[0031] Preferably, in step (1), the stirring time is 10 to 30 minutes and the stirring rate is 1500 r / min.

[0032] Preferably, in step (1), the settling time is 20-30 minutes. This allows the waste activated carbon powder and waste tire powder to disperse evenly, reducing the static fluidity of the slurry and preventing it from affecting the dispersion of the subsequent combustion accelerator.

[0033] Preferably, in step (2), the stirring time is 10 to 30 minutes and the stirring rate is 1000 r / min.

[0034] Preferably, in step (2), the settling time is 20 to 30 minutes, waiting for all components in the slurry to be evenly dispersed, thereby reducing the static fluidity of the slurry.

[0035] On the other hand, the present invention also provides an organic slurry, which is prepared by the method described above for preparing organic slurry using waste activated carbon and waste tires.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0037] This invention, based on the stability principle of solid-liquid mixtures and the combustion principle of mixed slurries, prepares a high-quality solid waste-based mixed organic slurry (coal-water slurry) by mixing waste tire powder and waste activated carbon powder. Waste tire powder has a high calorific value, high volatile matter, and good combustibility, but its density is low and it has few hydrophilic functional groups such as hydroxyl and carboxyl groups on its surface, resulting in poor slurry formation when used alone. Waste activated carbon, on the other hand, contains a large number of hydrophilic functional groups, such as hydroxyl and carboxyl groups, and has good water compatibility. Its density is higher than that of waste tire powder, and the addition of waste activated carbon can improve the fluidity and stability of the mixed slurry. However, its volatile matter content is low, its calorific value is low, and it is difficult to ignite when used alone. Therefore, mixing waste tire powder and waste activated carbon powder in a certain proportion to prepare a mixed organic slurry can improve the fluidity and stability of individual slurries while ensuring combustibility and calorific value. This achieves joint disposal and resource utilization of waste without the need for coal, which is in line with the concept of a circular economy. Attached Figure Description

[0038] Figure 1 The following are the Fourier Transmission Infrared (FTIR) spectra of waste tire powder and waste activated carbon powder in this invention.

[0039] Figure 2 This is a rheological curve of the waste tire and waste activated carbon mixed slurry of the present invention;

[0040] Figure 3 This is a stability index diagram of the waste tire and waste activated carbon mixed slurry of the present invention. Detailed Implementation

[0041] This invention patent proposes a method for the formulation and preparation of organic slurry from waste activated carbon and waste tires, which can significantly improve the stability and flowability of organic slurry from all solid waste.

[0042] Because activated carbon has a low calorific value and low volatile matter content, it is difficult to meet the gasification requirements of organic slurry. Therefore, there are almost no examples of using activated carbon alone as a carbon-based material to prepare organic slurry. Waste tires, however, have a high calorific value and high volatile matter content, which can compensate for the shortcomings of activated carbon during the gasification process of organic slurry. Furthermore, the doping of activated carbon can improve the stability of the waste tire organic slurry. Therefore, a specific embodiment of this invention proposes a method for the formulation and preparation of an organic slurry using activated carbon as the carbon-based material and doped with waste tires.

[0043] A specific embodiment of the present invention provides a method for preparing organic slurry using waste activated carbon and waste tires, comprising:

[0044] In this embodiment, coal-based activated carbon is used. The dried waste activated carbon and waste tires are placed in a ball mill and ground for 5 hours. The powders are then sieved through a 200-mesh sieve to obtain dry waste activated carbon powder and dry waste tire powder, which are used to prepare organic slurry.

[0045] Using dry pulping technology, firstly, the amount of waste activated carbon, waste tires, water, and each component in the additives required for pulping is calculated according to the preset concentration.

[0046] Next, the weighed portion of water is mixed with dodecyltrimethylammonium chloride, and the dodecyltrimethylammonium chloride and water are fully dissolved using a stirrer at a speed of 1500 r / min.

[0047] Then, pour the dried waste activated carbon powder and dried waste tire powder into the container, and continue to mix thoroughly with a stirrer at a speed of 1000 rpm for 10–30 minutes. After stopping the stirring, let it stand for 20–35 minutes.

[0048] Then, add sodium petroleum sulfonate and the remaining water, set the stirring speed to 1000 r / min, and stir for 10 to 30 minutes until the mixture is uniform and flows well.

[0049] Finally, turn off the agitator and let the homogeneous slurry stand for 20 to 35 minutes to release the air introduced into the slurry during the agitation process, thus completing the preparation.

[0050] Example 1

[0051] In this embodiment, the dispersant is dodecyltrimethylammonium chloride, the combustion promoter is sodium petroleum sulfonate, and the weight percentages of waste activated carbon powder, waste tire powder, water, dispersant, and combustion promoter are 40%, 1.3%, and 0.7%, respectively. 40g of organic slurry is prepared using coal-based activated carbon powder.

[0052] Example 2

[0053] In this embodiment, the dispersant is dodecyltrimethylammonium chloride, the combustion promoter is sodium petroleum sulfonate, and the preset weight percentages are: waste activated carbon powder 30%, waste tire powder 20%, water 48%, dispersant 1.3%, and combustion promoter 0.7%. 40g of organic slurry is prepared using coal-based activated carbon powder.

[0054] Example 3

[0055] In this embodiment, the dispersant is dodecyltrimethylammonium chloride, the combustion promoter is sodium petroleum sulfonate, and the preset weight percentages are: waste activated carbon powder 20%, waste tire powder 30%, water 48%, dispersant 1.3%, and combustion promoter 0.7%. 40g of organic slurry is prepared using coal-based activated carbon powder.

[0056] Example 4

[0057] In this embodiment, the dispersant is dodecyltrimethylammonium chloride, the combustion promoter is sodium petroleum sulfonate, and the weight percentages of waste activated carbon powder, waste tire powder, water, dispersant, and combustion promoter are 40%, 1.3%, and 0.7%, respectively. 40g of organic slurry is prepared using coal-based activated carbon powder.

[0058] Comparative Example 1

[0059] In this embodiment, the dispersant is dodecyltrimethylammonium chloride, the combustion promoter is sodium petroleum sulfonate, and the weight percentages of waste activated carbon powder, waste tire powder, water, dispersant, and combustion promoter are set at 0%, 50%, 48%, 1.3%, and 0.7%, respectively. 40g of organic slurry is prepared using coal-based activated carbon powder.

[0060] Performance Analysis:

[0061] The concentration values ​​provided in this embodiment of the invention are determined by referring to the method for measuring the concentration of organic slurry, according to the national standard GB / T18856.2-2008, using the drying oven method.

[0062] The viscosity values ​​provided in this embodiment of the invention are measured using a rotational rheometer to determine the apparent viscosity. The viscosity is measured at 100 s. -1 Within, the rotor's shear rate decreased from 0.01 s⁻¹. -1 Logarithm increased to 100s -1 The logarithm then decreases to 0.01s. -1 The shear rate is 100 s. -1 The viscosity value corresponding to this time is defined as the apparent viscosity of the slurry.

[0063] like Figure 1As shown, in the existing technology, waste tire powder has a high calorific value, high volatile content, and good combustibility, but its density is low and it has few hydrophilic functional groups such as hydroxyl and carboxyl groups on its surface. Figure 1 ), when prepared alone, it produces poor slurry properties; while the surface of waste activated carbon contains a large number of hydrophilic functional groups, such as hydroxyl and carboxyl groups ( Figure 1 It has good compatibility with water and a higher density than waste tire powder. The addition of waste activated carbon can improve the fluidity and stability of the mixed slurry, but its volatile content is low, its calorific value is low, and it is difficult to ignite when mixed alone.

[0064] like Figure 2 and Figure 3 As shown in Examples 2-4 of the present invention, waste tire powder and waste activated carbon powder are mixed in a certain proportion to prepare a mixed organic slurry, which can improve the fluidity of the slurry prepared individually. Figure 2 ) and stability ( Figure 3 This ensures both flammability and calorific value.

[0065] The stability values ​​provided in this embodiment of the invention were measured using a Turbiscan Lab stability analyzer.

[0066] The calorific value provided in this embodiment of the invention is measured by a calorimeter.

[0067] The properties of the organic slurries prepared in Examples 1-4 and Comparative Example 1 are shown in Table 1.

[0068] Table 1. Properties of the organic slurries prepared in Examples 1-4 and Comparative Example 1

[0069]

[0070]

[0071] As shown in Table 1, the calorific value of the organic slurry prepared in Examples 1-4 and Comparative Example 1 gradually increased with the increase of the amount of dry waste tire powder added. By adding waste tires and waste activated carbon, the upper limit of the concentration of the prepared organic slurry was increased to 48.9%, which made the prepared organic slurry beneficial to improving the productivity and conversion rate of the gasifier.

[0072] The stability of the organic slurry prepared in Examples 1 to 4 of this invention is significantly higher than that of the organic slurry prepared in Comparative Example 1. Therefore, the stability of the prepared organic slurry can be significantly enhanced by adding waste activated carbon. The hydrophilicity of activated carbon can, to a certain extent, enable the hydrophobic waste tire powder to be slurried better.

[0073] By adding appropriate amounts of dry waste activated carbon powder and dry waste tire powder, the stability, calorific value and slurry concentration of the prepared organic slurry were significantly improved through synergistic effect.

[0074] The activated carbon organic slurry of the present invention has a concentration of about 48% and a viscosity of 700-900 mPa·s, which meets the actual requirements of industrial production (45-60%). The viscosity and calorific value also meet the actual production requirements. It has good slurry-forming performance and excellent stability.

[0075] Table 2 Industrial and elemental analysis of activated carbon and tire powder

[0076]

[0077] In the table: M, A, V, and FC represent moisture, ash, volatile matter, and fixed carbon content, respectively; Q b,ad The value is indicated by: calorific value; C, H, O, and N represent the content of carbon, hydrogen, oxygen, and nitrogen elements, respectively; St represents the total sulfur content; ad, d, and daf represent air-dried basis, dry basis, and dry ash-free basis, respectively.

[0078] As shown in Table 2, activated carbon and tire powder both have calorific values ​​no lower than those of coal, and their related properties, such as sulfur content and ash content, are also low. They can effectively replace coal in the preparation of high-quality organic slurry.

Claims

1. A method for preparing organic slurry using waste activated carbon and waste tires, characterized in that, include: (1) Mix dry waste activated carbon powder, dry waste tire powder, dispersant and water evenly and let stand to obtain a mixture; (2) Add the combustion accelerator and water to the mixture obtained in step (1), stir evenly, and let stand to obtain an organic slurry; The dried waste activated carbon powder is any one of coal-based activated carbon, wood-based activated carbon, and coconut shell activated carbon. The weight ratio of the dried waste activated carbon powder, dried waste tire powder, dispersant, combustion accelerator, and water is: 20-40 wt% of dried waste activated carbon powder 10-50 wt% dry waste tire powder Water 48-49wt%; Dispersant 0.5~2 wt%; Combustion accelerator 0.5~2 wt%; The sum of the weight ratios of the dry waste activated carbon powder, dry waste tire powder, dispersant, combustion accelerator, water, and unavoidable impurities is 100 wt.

2. The method for preparing organic slurry using waste activated carbon and waste tires according to claim 1, characterized in that, The weight ratio of the dried waste activated carbon powder, dried waste tire powder, dispersant, combustion accelerator, and water is: 20 wt% of dried waste activated carbon powder 30 wt% of dry waste tire powder Water 48 wt% Dispersant 1.7 wt%; Combustion accelerator 0.3 wt%; Within this range, the stability value is 4.6, measured using a Turbiscan Lab stability analyzer. The calorific value is 28.87 MJ / kg, and the viscosity is 735 mPa·s.

3. The method for preparing organic slurry using waste activated carbon and waste tires according to claim 1, characterized in that, The dispersant is at least one of sodium methylene bisnaphthalene sulfonate, sodium lignin sulfonate, and dodecyltrimethylammonium chloride.

4. The method for preparing organic slurry using waste activated carbon and waste tires according to claim 1, characterized in that, The combustion promoter is at least one of sodium petroleum sulfonate and sodium naphthenate.

5. The method for preparing organic slurry using waste activated carbon and waste tires according to claim 1, characterized in that, In step (1), the stirring time is 10-30 min, the stirring rate is 1500 r / min, and the settling time is 20-30 min.

6. The method for preparing organic slurry using waste activated carbon and waste tires according to claim 1, characterized in that, In step (2), the stirring time is 10-30 min, the stirring rate is 1000 r / min, and the settling time is 20-30 min.

7. An organic slurry, characterized in that, The organic slurry is prepared according to any one of claims 1-6 using waste activated carbon and waste tires.

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