Method for upgrading coal tar pitch and oil sludge by co-pyrolysis and carbon black raw material

Abstract

The present application belongs to the technical field of energy products, and particularly relates to a method for upgrading coal pitch and oil sludge by co-pyrolysis and a carbon black raw material, comprising the following steps: S1, pre-degradation: degrading organic alkali, thick oil ester, inorganic heavy metal ions and fillers in the oil sludge by actinomycetes and bacillus; the classification name of the bacillus is Bacillus aryabhattai, the preservation address is China Center for Type Culture Collection, and the preservation number is CCTCC NO: M20232038; S2, co-pyrolysis: co-pyrolyzing the oil sludge after pre-degradation in step S1 under oxygen-rich fuel gas and carbon black tail gas CO2 and coal pitch, and obtaining a derivative. Through pre-degradation, co-pyrolysis, fractional distillation or reaction rectification, the utilization rate of oil product resources of the waste oil sludge is 85-90%, and the remaining 10-15% is used as filler carbon black.

Description

Technical Field

[0001] This invention belongs to the field of energy product technology, specifically relating to a method for upgrading coal tar pitch and oil sludge through co-pyrolysis and carbon black raw materials. Background Technology

[0002] Oil drilling operations utilize lignite and humic acid as oilfield additives. Therefore, the waste oil sludge from the extraction sites contains heavy oil, polycyclic aromatic hydrocarbons, and other organic pollutants, as well as soluble inorganic salts, such as Cl. - , SO4, Na+ and Ca 2+ Using oilfield immobilized microorganisms technology to treat contaminated oil sludge in situ using chemical or physical means is one way to alleviate waste oil sludge pollution.

[0003] Ren Lijun et al. from Tianjin University of Science and Technology isolated three petroleum hydrocarbon-degrading bacteria from oily sludge in the Bohai Oilfield. The 16S rRNA gene sequences identified them as Corynebacterium, Short Bacillus, and Pseudomonas. Single-factor experiments determined that the degradation rates of total petroleum hydrocarbons in oily sludge at 37℃, salinity 1-3%, pH 6-8, 32℃, and 30 days were 39.69% and 53.29%, respectively. The degradation effect of mixed bacteria was significantly higher than that of single strains, with a degradation rate of 58.08%. GC-MS analysis showed that mixed bacteria significantly degraded n-C12 to n-C34 n-alkanes and had a strong ability to degrade polycyclic aromatic hydrocarbons such as naphthalene, acenaphthene, chrysene, and benzo[a]fluoranthene (Ren Lijun, Liu Xianbin, Tian Shengyan, Isolation and degradation characteristics of petroleum-degrading bacteria in oily sludge. Journal of Environmental Engineering, 2015, 9(7): 3538-3544). However, the limitations of oily sludge raw materials and the fact that the degradation mainly consisted of organic matter such as petroleum polycyclic aromatic hydrocarbons did not address the degradation of inorganic heavy metal compounds in drilling mud oily sludge.

[0004] The utility model patent with patent application number CN207552228 discloses a device for producing carbon black from oil sludge, which can utilize oil and combustibles and eliminate the pollution of the environment by oil sludge, but does not include any process or parameters.

[0005] Yu Yinguo of Jiangsu Guoruit Environmental Protection Engineering Technology Co., Ltd. believes that the conventional waste pyrolysis process for treating oil sludge not only incurs extremely high costs in terms of kerosene and fuel, but also generates harmful fly ash and particulate pollutants containing dioxins during the pyrolysis process. The treatment of oil sludge can be improved in terms of both environmental protection and economy by replacing the pyrolysis furnace equipment or improving the process (Research and Application of Low-Temperature Pyrolysis Treatment Technology for Oil Sludge Solid Waste [J]. Engineering Technology, 2022(2):248-251). Currently, this research is in the process of proposal and exploration, and does not involve high-pour-point oil sludge. Summary of the Invention

[0006] To address the aforementioned technical problems, one objective of this invention is to provide a method for upgrading coal tar pitch and oil sludge through co-pyrolysis. This method utilizes the properties of actinomycetes to reduce salt and alkali and thus inorganic heavy metal compounds, and utilizes the property of Bacillus aureus to convert inorganic silicon into organic silicon, thereby treating drilling mud and oil sludge and upgrading coal tar pitch and oil sludge through co-pyrolysis. Another objective of this invention is to provide a carbon black raw material.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0008] A method for upgrading coal tar pitch and oil sludge through co-pyrolysis includes the following steps:

[0009] S1. Pre-degradation: Organic alkalis, heavy oil esters, inorganic heavy metal ions and fillers in oil sludge are degraded by actinomycetes and Bacillus.

[0010] The Bacillus species is classified as Bacillus argentis, and its deposit address is China Center for Type Culture Collection, with accession number CCTCC NO: M20232038 and deposit date of October 25, 2023.

[0011] S2, Co-pyrolysis: The oil sludge pre-degraded in step S1 is co-pyrolyzed with coal tar pitch under oxygen-enriched fuel gas and carbon black tail gas CO2 to obtain derivatives.

[0012] Preferably, in step S1, the actinomycetes underwent 16S rDNA fragment amplification optimization.

[0013] Preferably, in step S1, under the action of actinomycetes and Bacillus halophilus, at a CFU / kg oil sludge temperature of 10-40℃, pH 7.0-10.0, and a time of 40-60 min, the hydrophilic hydroxyl groups (-OH) of the oil sludge transform the -SiO2 coated with the filler into Si(OR)4+H2O.

[0014] In step S2, organic base and heavy oil ester are intercalated and modified by reaction of oxygen-enriched fuel gas and carbon black tail gas CO2.

[0015] Preferably, in step S1, the trace amounts of miscellaneous salts in the oil sludge can be used as a culture medium for actinomycetes and Bacillus aureus, wherein the mass percentages are as follows: chloride ions 0.02%, sulfate ions, sodium ions 0.10%, calcium ions 0.05%, and the phase is transferred to the non-oil phase of the actinomycete recycling phase during culture.

[0016] Preferably, in step S2, the derivatives obtained by pyrolysis include "linear alkyl acid" derivatives, "linear oleamide" derivatives, and "benzonaphthalene derivatives".

[0017] Preferably, in step S2, the mass ratio of sludge to coal tar pitch is 2:1, and the ratio of straight-chain hydrocarbons to aromatic hydrocarbons in the product is 1.5:1, making it a high-quality carbon black raw material for inks, with a DBP absorption value of 125-130 cm / 100g.

[0018] An ink carbon black raw material can be prepared by co-pyrolyzing coal tar pitch and oil sludge according to the above-mentioned method, and then purifying it through a fractionation tower.

[0019] A conductive carbon black raw material is obtained by co-pyrolyzing coal tar pitch and oil sludge according to the above-mentioned method, and then further purifying it in a reactive distillation column to obtain a conductive carbon black raw material for high-voltage submarine cable shielding.

[0020] Compared with the prior art, the beneficial effects of this invention are:

[0021] It is first degraded by actinomycetes and Bacillus argentis; then it is co-pyrolyzed with coal tar pitch under the CO2 of oxygen-enriched carbon black tail gas, resulting in the formation of "straight-chain alkyl acids", "straight-chain oleamide" derivatives, and "benzo[a]naphthalene" derivatives.

[0022] The production system of coal tar pitch carbon black was improved and utilized. The co-pyrolysis upgrading technology was used to improve the quality of ink carbon black, meet the quality requirements of conductive carbon black for semi-conductive shielding materials of high-voltage cables, and effectively regulate the CO2 in oxygen-enriched fuel and carbon black tail gas to improve the quality of oil sludge, save energy and reduce emissions, and increase the economic benefits of by-product filler carbon black.

[0023] The mass ratio of oil sludge to coal tar pitch is 2:1, and the ratio of straight-chain hydrocarbons to aromatic hydrocarbons in the product is 1.5:1, making it a high-quality carbon black raw material for inks. The DBP absorption value is 125-130 cm / 100g.

[0024] The conductive carbon black raw material for high-voltage submarine cable shielding is further purified in a reactive distillation column. It has the following properties: pH (according to GB / T 3780.7 standard) 7.0-8.0, oil absorption value-DBP absorption value (according to GB / T 3780 standard) 138-148 cm / 100g, ash content (according to GB / T3780.10 standard) <0.1%, volume resistivity (according to JB / T 10738, GB / T3048.3 standard) 2.6-3.0 Ω·cm, particle size 30-40nm, and residue content on a 325-mesh sieve <6ppm, meeting the quality standards for conductive carbon black raw materials used in high-voltage submarine cable shielding.

[0025] Through pre-degradation, co-pyrolysis, fractionation or reactive distillation, the utilization rate of oil resources in waste oil sludge is 85-90%, and the remaining 10-15% is used as filler carbon black. Attached Figure Description

[0026] Figure 1This is a schematic diagram of the process equipment operation flow of the present invention;

[0027] Figure 2 This is a GC-MS representation of the "straight-chain alkyl acid" derivative, a product of the co-pyrolysis of this invention.

[0028] Figure 3 This is a GC-MS representation of the "linear oleamide" derivative, a co-pyrolysis product of this invention.

[0029] Figure 4 This is a GC-MS representation of the "benzonaphthalene" derivative, a co-pyrolysis product of this invention.

[0030] Among them: 1 is carbon black tail gas, 2 is nitrogen, 3 is waste oil sludge, 4 is fractionation or reactive distillation tower, 5 is pyrolysis furnace, 6 is dust collector, 7 is oxygen-enriched gas control, 8 is condenser, 9 is compressor, and 10 is recyclable CO2. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0032] A method for upgrading coal tar pitch and oil sludge through co-pyrolysis includes the following steps:

[0033] S1. Organic alkalis, heavy oil esters, heavy metal ions, etc. in oil sludge are first degraded by actinomycetes and Bacillus.

[0034] S2, when co-pyrolyzed with coal tar pitch under CO2 in the tail gas of oxygen-enriched carbon black, derivatives such as "straight-chain alkyl acids" and "straight-chain oleamides" are formed, as well as derivatives such as "benzo[a]naphthalenes" (e.g.) Figure 2-4 (As shown).

[0035] Specifically, the 16S rDNA fragment of the actinomycetes that degrade organic alkalis, heavy oil esters, inorganic heavy metal ions in oil sludge was amplified and optimized. The Bacillus species is classified as Bacillus argentis, and its deposit address is China Center for Type Culture Collection, with accession number CCTCC NO: M20232038 and deposit date of October 25, 2023.

[0036] This method enables the utilization rate of oil resources in waste oil sludge to reach 85-90% (the remaining 10-15% is used as filler carbon black). After purification in a fractionation tower, it can be made into high-quality ink carbon black raw material. Furthermore, by further purification in a reactive distillation tower for conductive carbon black raw materials, it can reach the quality of conductive carbon black raw material used for high-voltage submarine cable shielding.

[0037] like Figure 1As shown, the main process equipment used includes a fractionation or reactive distillation column 4, a pyrolysis furnace 5 (which periodically removes usable carbon black particles), a dust collector 6, a condenser 8, and a compressor 9. Among them, 1 and 2 are for carbon black tail gas and nitrogen inlet and outlet; 3 is for waste oil sludge inlet (which has been treated by actinomycetes and Bacillus); and 10 is for conveying recyclable CO2.

[0038] To further illustrate this point, the following examples are provided.

[0039] Example 1:

[0040] This embodiment uses 100 parts of waste oily sludge from used lignite humic acid drilling mud and coal tar pitch, including 65 parts of water-containing heavy oil, 2 parts of kaolin and heavy metal compounds, and 1 part of actinomycetes 2 with a water content of 95% and Bacillus oryzae (accession number: 20232038) at a concentration of U 1.0 / kg oily sludge. The mixture is reacted at 30℃ and pH 7.0 for 35 minutes. -1 Ca 2+ SO4 2+ After being transferred to a non-oil phase actinomycete and Bacillus argentis layer, it is then co-pyrolyzed with 30 parts of coal tar pitch containing polycyclic aromatic hydrocarbons (PAHs) at 500°C under the regulation of oxygen-enriched fuel gas and CO2 tail gas to form "straight-chain alkanoic acid", "straight-chain oleamide" derivatives, and "benzo[a]naphthalene" derivatives, etc. After purification by a fractionation tower, the utilization rate of oil resources in waste oil sludge is 87%. As a raw material for ink carbon black, with a DBP absorption value of 125 cm / 100g, it can be added to coatings to improve the hiding power, weather resistance and corrosion resistance of the coating, and produce 15% filler carbon black as a by-product.

[0041] Example 2:

[0042] This embodiment uses 100 parts of waste oily sludge from used lignite humic acid drilling mud and coal tar pitch, including 65 parts of water-containing heavy oil, 2 parts of kaolin and heavy metal compounds, and 1 part of actinomycetes 2 with a water content of 95% and Bacillus oryzae (accession number: 20232038) at a concentration of U 1.0 / kg oily sludge. The mixture is reacted at 35℃ and pH 7.5 for 50 min. Cl... -1 Ca 2+ SO4 2+ After being transferred to the non-oil phase actinomycete and Bacillus argentis layer, it is then co-pyrolyzed with 30 parts of coal tar pitch containing polycyclic aromatic hydrocarbons (PAHs) at 550°C by regulating with oxygen-enriched fuel gas and CO2 tail gas to form "straight-chain alkanoic acid", "straight-chain oleamide" derivatives, and "benzo[a]naphthalene" derivatives, etc. After purification by a fractionation tower, the utilization rate of oil resources of waste oil sludge is 90%. As a raw material for ink carbon black, the DBP absorption value is 130 cm / 100g, and 10% filler carbon black is also produced as a by-product.

[0043] Example 3:

[0044] This embodiment uses 100 parts of waste oily sludge from used lignite humic acid drilling mud and coal tar pitch, including 65 parts of water-containing heavy oil, 2 parts of kaolin and heavy metal compounds, and 1 part of actinomycetes 2 with a water content of 95% and Bacillus argentis (accession number: 20232038). The concentration is 1.0 U / kg oily sludge. The mixture is reacted at 40℃ and pH 8.0 for 40 min. Cl -1 Ca 2+ SO4 2+ After being transferred to the non-oil phase actinomycete and Bacillus argentis layer, it is then co-pyrolyzed with 30 parts of coal tar pitch containing polycyclic aromatic hydrocarbons (PAHs) at 550°C under the regulation of oxygen-enriched fuel gas and CO2 tail gas to form "straight-chain alkyl acids", "straight-chain oleamide" derivatives, and "benzo[a]naphthalene" derivatives, etc. This co-pyrolyzed oil is further purified in a reactive distillation column to achieve a pH of 8.0, an oil absorption value-DBP absorption value of 146 cm / 100g, a particle size of 38nm, an ash content of <0.1%, a resistivity of 3.0Ω·cm, and a residue content of <6ppm on a 325-mesh sieve, reaching the quality of conductive carbon black raw material for high-voltage submarine cable shielding; the oil utilization rate is 85%, and the remaining 15% is used as filler carbon black.

[0045] The above description only illustrates preferred embodiments of the present invention, but the present invention is not limited to the above embodiments.

Claims

1. A method for upgrading coal tar pitch and oil sludge by co-pyrolysis, characterized in that, Includes the following steps: S1. Pre-degradation: Organic alkalis, heavy oil esters, inorganic heavy metal ions and fillers in oil sludge are degraded by actinomycetes and Bacillus. The Bacillus species is classified as Bacillus argentis, and its deposit address is China Center for Type Culture Collection, with accession number CCTCC NO: M20232038 and deposit date of October 25, 2023. S2, Co-pyrolysis: The oil sludge pre-degraded in step S1 is co-pyrolyzed with coal tar pitch under oxygen-enriched fuel gas and carbon black tail gas CO2 to obtain derivatives.

2. The method for upgrading coal tar pitch and oil sludge by co-pyrolysis according to claim 1, characterized in that: In step S1, the actinomycetes underwent 16S rDNA fragment amplification optimization.

3. The method for upgrading coal tar pitch and oil sludge through co-pyrolysis according to claim 1, characterized in that: In step S1, under the action of actinomycetes and Bacillus argentis, oil sludge is treated at a rate of 1.0 CFU / kg at a temperature of 10-40℃, a pH of 7.0-10.0, and a time of 40-60 min, so that the hydrophilic hydroxyl groups of the oil sludge can transform the -SiO2 coated with the filler into Si(OR)4+H2O. In step S2, organic base and heavy oil ester are intercalated and modified by reaction of oxygen-enriched fuel gas and carbon black tail gas CO2.

4. The method for upgrading coal tar pitch and oil sludge through co-pyrolysis according to claim 1, characterized in that: In step S1, trace amounts of miscellaneous salts in the oil sludge serve as a culture medium for actinomycetes and Bacillus aureus, with the following mass percentages: chloride ions 0.02%, sulfate ions, sodium ions 0.10%, and calcium ions 0.05%, and are transferred to the non-oil phase of the actinomycete recycling phase during culture.

5. The method for upgrading coal tar pitch and oil sludge through co-pyrolysis according to claim 1, characterized in that: In step S2, the derivatives obtained by pyrolysis include "straight-chain alkyl acid" derivatives, "straight-chain oleamide" derivatives, and "benzonaphthalene derivatives".

6. The method for upgrading coal tar pitch and oil sludge through co-pyrolysis according to claim 1, characterized in that: In step S2, the mass ratio of oil sludge to coal tar pitch is 2:1, and the ratio of straight-chain hydrocarbons to aromatic hydrocarbons in the product is 1.5:1, making it a high-quality carbon black raw material for inks, with a DBP absorption value of 125-130 cm / 100g.

7. A carbon black raw material for inks, characterized in that: According to any one of claims 1 to 6, a method for upgrading coal tar pitch and sludge by co-pyrolysis is used. After co-pyrolysis, the raw material for ink carbon black is purified by a fractionation tower.

8. A conductive carbon black raw material, characterized in that: After co-pyrolysis of coal tar pitch and sludge according to any one of claims 1 to 6, the mixture is further purified in a reactive distillation column to obtain conductive carbon black raw material for high-voltage submarine cable shielding.

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