CN111334324A - Production method of high-quality wash oil and coal tar processing method - Google Patents
Production method of high-quality wash oil and coal tar processing method Download PDFInfo
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- CN111334324A CN111334324A CN202010223495.XA CN202010223495A CN111334324A CN 111334324 A CN111334324 A CN 111334324A CN 202010223495 A CN202010223495 A CN 202010223495A CN 111334324 A CN111334324 A CN 111334324A
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G7/00—Distillation of hydrocarbon oils
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10C—WORKING-UP PITCH, ASPHALT, BITUMEN, TAR; PYROLIGNEOUS ACID
- C10C1/00—Working-up tar
- C10C1/04—Working-up tar by distillation
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- General Chemical & Material Sciences (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
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Abstract
The invention belongs to the field of coal tar processing, and particularly relates to a production method of high-quality wash oil and a coal tar processing method. The production method of the high-quality wash oil comprises the following steps: carrying out primary distillation on the wash oil at a first distillation temperature to separate out naphthalene-rich fraction and mixed oil of naphthalene removal; carrying out secondary distillation on the mixed oil at a second distillation temperature to separate high-quality wash oil and heavy oil, wherein the specification of the high-quality wash oil is as follows: distillate quantity before 230 ℃: none, the distillate yield before 270 ℃ is more than or equal to 90 percent, and the distillate yield before 300 ℃ is more than or equal to 96 percent; the naphthalene content is less than or equal to 5 percent. According to the production method of the high-quality wash oil, the light components such as naphthalene and the heavy components such as anthracene are separated out through secondary distillation of the wash oil, so that the produced wash oil meets the set technical index requirements, the application effect of the wash oil in benzene washing is optimized, and the quality of the wash oil is improved.
Description
Technical Field
The invention belongs to the field of coal tar processing, and particularly relates to a production method of high-quality wash oil and a coal tar processing method.
Background
Coal tar is black brown and viscous oily liquid obtained in the processes of dry distillation and gasification of coal, and can be divided into low-temperature coal tar (the dry distillation temperature is 450-600 ℃), medium-temperature coal tar (the dry distillation temperature is 700-900 ℃) and high-temperature coal tar (the dry distillation temperature is about 1000 ℃) according to different dry distillation temperatures and process methods. High temperature coal tar is mainly a complex mixture composed of aromatic hydrocarbons, and many of the compounds are industrial raw materials such as plastics, synthetic fibers, fuels, synthetic rubbers, pesticides, medicines, high temperature resistant materials and the like.
The coal tar processing is to separate light oil, phenol oil, naphthalene oil, wash oil, anthracene oil, asphalt and other components through a distillation process, wherein the wash oil is one of important fractions in the coal tar rectification process, the boiling range is 230-300 ℃, and accounts for about 4.5-10% of the coal tar, and 149 components analyzed in the wash oil currently contain a plurality of valuable aromatic compounds, such as naphthalene, α -methylnaphthalene, β -methylnaphthalene, dimethylnaphthalene, indole, biphenyl, acenaphthene, fluorene, dibenzofuran and the like.
For a long time, the washing oil is mainly used for washing and absorbing benzene hydrocarbon and various organic gases in the coke oven gas, and a small part of the washing oil is sold as raw oil and raw materials for preparing carbon black. Because of different processes for cutting and taking the washing oil fractions by different manufacturers, the fluctuation range of the component content in the washing oil is large. In the practical application of the washing oil and benzene, the washing oil prepared by processing the coal tar at present has larger consumption, and the efficiency of washing and absorbing benzene and benzene hydrocarbon needs to be improved.
Disclosure of Invention
The invention aims to provide a production method of high-quality wash oil, which aims to solve the problems that the conventional wash oil is large in dosage and the washing efficiency needs to be improved when being applied to benzene washing.
The second purpose of the invention is to provide a coal tar processing method.
In order to realize the purpose, the technical scheme of the production method of the high-quality wash oil is as follows:
a production method of high-quality wash oil comprises the following steps: carrying out primary distillation on the wash oil at a first distillation temperature to separate out naphthalene-rich fraction and mixed oil of naphthalene removal; carrying out secondary distillation on the mixed oil at a second distillation temperature to separate high-quality wash oil and heavy oil, wherein the specification of the high-quality wash oil is as follows: distillate quantity before 230 ℃: none, the distillate yield before 270 ℃ is more than or equal to 90 percent, and the distillate yield before 300 ℃ is more than or equal to 96 percent; the naphthalene content is less than or equal to 5 percent.
According to the production method of the high-quality wash oil, the light components such as naphthalene and the heavy components such as anthracene are separated out through secondary distillation of the wash oil, so that the produced wash oil meets the technical index requirements, the application effect of the wash oil in benzene washing is optimized, and the quality of the wash oil is improved.
The primary distillation is mainly for separating the naphthalene component, and generally, the naphthalene content in the naphthalene-rich fraction is 80% by volume or more. Further, the optimal primary distillation temperature can be determined by distillation experiments according to the naphthalene content, and preferably, the primary distillation temperature is 300-308 ℃.
The secondary distillation satisfies the specification that the light components reach high-quality wash oil, the lower the naphthalene content is, the better the fraction index of the corresponding distillation range (270 ℃, 300 ℃) is than the index value, the better the quality of the wash oil is, and the preferred temperature of the secondary distillation is 310-.
The high-quality wash oil obtained by the method is rich in components such as methylnaphthalene (with a boiling range of 235-250 ℃), dimethylnaphthalene (with a boiling range of 250-270 ℃) and the like, and can be used as a high-quality raw material for washing benzene oil or preparing gasoline and diesel oil by hydrogenation.
The produced high-quality wash oil can reach the following technical indexes: density (20 ℃): 1.03-1.05g/cm3(ii) a Distillation range (101.3 kPa): the distillate quantity (volume fraction) before 230 ℃ is not less than 90 percent, the distillate quantity (volume fraction) before 270 ℃ is more than or equal to 96 percent, and the distillate quantity (volume fraction) before 300 ℃; the naphthalene content (volume fraction) is less than or equal to 5 percent; the water content (mass fraction) is less than or equal to 0.5 percent.
The technical scheme adopted by the coal tar processing method is as follows:
a coal tar processing method comprises the following steps: distilling and separating coal tar to separate washing oil, and carrying out primary distillation on the washing oil at a first distillation temperature to separate naphthalene-rich fraction and naphthalene-removed mixed oil; carrying out secondary distillation on the mixed oil at a second distillation temperature to separate high-quality wash oil fraction and heavy oil, wherein the specification of the high-quality wash oil is as follows: distillate quantity before 230 ℃: none, the distillate yield before 270 ℃ is more than or equal to 90 percent, and the distillate yield before 300 ℃ is more than or equal to 96 percent; the naphthalene content is less than or equal to 5 percent.
The washing oil separated from the coal tar can refer to the related prior art, and various process routes can be adopted, for example, the washing oil fraction can be directly obtained by cutting the side line of a coal tar fraction tower, and the washing oil can also be obtained by distilling and separating three mixed oil or two mixed oil. The high-quality wash oil can be prepared by adopting the method provided by the invention.
According to the processing method of the coal tar, the washing oil obtained by the existing method is finely processed to prepare the high-quality washing oil, so that the application effect of the washing oil as benzene washing oil or hydrogenation gasoline and diesel oil is improved, and the industrial added value of the coal tar processing is improved.
Preferably, the coal tar distillation separation comprises the steps of separating out three-mixed oil from coal tar by distillation, washing the three-mixed oil, removing phenol, and then carrying out industrial naphthalene distillation to separate out the wash oil and the industrial naphthalene;
producing industrial naphthalene by utilizing the naphthalene-rich fraction separated by the primary distillation of the wash oil; and combining the industrial naphthalene separated by the industrial naphthalene distillation and the industrial naphthalene produced by the naphthalene-rich fraction. In the actual industrial production, the naphthalene content in the naphthalene-rich fraction is not constant, and at the initial extraction stage, the naphthalene content is about 80 percent, and the naphthalene can be mixed into three-mixed oil for distillation and separation to obtain industrial naphthalene; in the middle stage of production, the naphthalene content reaches 95%, and the industrial naphthalene can be collected by directly utilizing the existing industrial naphthalene production device. In the process of collecting the naphthalene-rich fraction, the naphthalene-rich fraction can be flexibly treated according to the naphthalene content, or mixed with three mixed oil and subjected to distillation separation to produce industrial naphthalene; or the naphthalene-rich fraction meeting the industrial naphthalene requirement is combined with industrial naphthalene produced in other sections.
In order to further improve the quality of the anthracene oil, preferably, the coal tar distillation separation comprises the step of distilling and separating the anthracene oil from the coal tar, and the anthracene oil and the heavy oil separated by the secondary distillation are combined to produce the high-quality anthracene oil. The anthracene oil separated from the heavy oil and the coal tar is mixed, and the mixing is not limited in proportion. After mixing, the density and carbon residue of the anthracene oil can be correspondingly reduced, and the distillate quantity at 300-360 ℃ can be improved, so that the quality of the anthracene oil is improved.
In order to further increase the naphthalene content of the naphthalene-rich fraction obtained in the first distillation, it is preferred that the temperature of the first distillation is 300-308 ℃. In order to further improve the quality of the high-quality wash oil, the temperature of the secondary distillation is preferably 310-320 ℃.
Detailed Description
The following examples are provided to further illustrate the practice of the invention.
The following example specifically illustrates the production process of high-quality wash oil by using the wash oil produced by the tar processing device of henan kaihuan carbon new material limited company as a raw material. The specifications of the original wash oil are shown in table 1.
TABLE 1 technical indices of the original wash oils
First, the specific embodiment of the method for producing high-quality wash oil of the present invention
Example 1
The production method of the high-quality wash oil adopts the following steps:
1) transferring 600mL of original wash oil into a 1000mL distillation flask, connecting a distillation device with a fractionating column, and carrying out primary distillation at 304 ℃ to obtain naphthalene-rich fraction and mixed oil with naphthalene removed. The naphthalene content of the naphthalene-rich fraction was 90% by volume.
2) Performing secondary distillation on the mixed oil at 315 ℃ to obtain high-quality wash oil fraction and heavy oil, wherein the specification of the high-quality wash oil fraction is as follows:
density (20 ℃): 1.05g/cm3；
Distillation range (atmospheric pressure 101.3 kPa): distillate quantity before 230 ℃: none; distillate quantity before 270 ℃ (volume fraction): 90%, distillate amount (volume fraction) before 300 ℃: 96 percent;
naphthalene content (volume fraction): 5 percent;
water content (mass fraction): 0.5 percent.
Example 2
The production method of the high-quality wash oil of the embodiment is different from the production method of the embodiment 1 in that:
in the step 1), the temperature of the primary distillation is 303 ℃, and the volume content of naphthalene in the naphthalene-rich fraction is 92%.
In the step 2), the temperature of the secondary distillation is 313 ℃, and the specification of the high-quality wash oil fraction is as follows:
density (20 ℃): 1.05g/cm3；
Distillation range (atmospheric pressure 101.3 kPa): distillate quantity before 230 ℃: none; distillate quantity before 270 ℃ (volume fraction): 91%, distillate amount (volume fraction) before 300 ℃: 96.5 percent;
naphthalene content (volume fraction): 4.5 percent;
water content (mass fraction): 0.5 percent.
Example 3
The production method of the high-quality wash oil of the embodiment is different from the production method of the embodiment 1 in that:
in the step 1), the temperature of the primary distillation is 302 ℃, and the volume content of naphthalene in the naphthalene-rich fraction is 95%.
In the step 2), the temperature of the secondary distillation is 317 ℃, and the specification of the high-quality wash oil fraction is as follows:
density (20 ℃): 1.04g/cm3；
Distillation range (atmospheric pressure 101.3 kPa): distillate quantity before 230 ℃: none; distillate quantity before 270 ℃ (volume fraction): 92%, distillate amount before 300 ℃ (volume fraction): 97 percent;
naphthalene content (volume fraction): 4 percent;
water content (mass fraction): 0.4 percent.
Example 4
In the production method of the high-quality wash oil of the embodiment, the technical indexes of the original wash oil are shown in table 1, the distillation tower is adopted for industrial production, the temperature of the bottom of the distillation tower is controlled to be 304 ℃, the temperature of the top of the distillation tower is controlled to be 210-235 ℃ during primary distillation, naphthalene-rich fraction is extracted from the top of the distillation tower, and the mixed oil of naphthalene removal is obtained from the bottom of the distillation tower. The naphthalene content of the naphthalene-rich fraction changes along with the distillation process, naphthalene oil with the naphthalene content of about 80% is produced in the initial stage of production, and industrial naphthalene with the naphthalene content of more than 95% is produced in the middle stage of production. The naphthalene oil obtained in the initial stage of extraction can be added into the three-mixed oil to continue the production of industrial naphthalene, and the industrial naphthalene obtained in the middle stage of extraction is sold as a finished product.
And (3) carrying out secondary distillation on the mixed oil after naphthalene removal, controlling the temperature of the bottom of the distillation tower to be 315 ℃, the temperature of the top of the distillation tower to be 230-260 ℃, obtaining high-quality wash oil at the top of the distillation tower, and obtaining heavy oil at the bottom of the distillation tower.
Second, the concrete embodiment of the coal tar processing method of the present invention
Example 5
The coal tar processing method comprises the following steps: distilling and separating coal tar to obtain light oil, three-mixed oil, anthracene oil and pitch, washing the three-mixed oil, dephenolizing, and then carrying out industrial naphthalene distillation to obtain phenol oil, industrial naphthalene and wash oil. The wash oil was used to produce high quality wash oil as in example 4, wherein the naphthalene rich fraction was used to produce industrial naphthalene and the heavy oil component was mixed with the anthracene oil.
In the whole production process, the quality of the washing oil is further improved, the washing oil can be used as high-quality washing benzene oil, compared with the traditional washing oil, the washing efficiency is further improved, and the using amount is further reduced.
Compared with the prior art, the yield of the industrial naphthalene is improved from 8-9% to 10-11%, and the yield of the industrial naphthalene is further improved.
Mixing heavy oil and anthracene oil, and further optimizing density, carbon residue and distillation range index of anthracene oil, wherein the density is 1.16g/cm3Reduced to 1.14g/cm3(ii) a The carbon residue is reduced from 1.2 percent to 0.5 percent; distillation range: the distillate yield is improved from 50% to 60-65% before 360 ℃. The above indexes further optimize the quality of anthracene oil.
In conclusion, the coal tar processing method improves the yield of industrial naphthalene, optimizes the quality of wash oil and anthracene oil, and realizes the fine processing of coal tar.
Third, Experimental example
Experimental example 1
The high-quality wash oil obtained in example 1 is applied to the benzene washing of coke oven gas, and due to the enrichment of effective components, substances which have adverse effects on the benzene washing are separated, and the monthly usage amount of the wash oil is reduced by 30% under the same benzene washing workload. The method reduces the dosage of the washing oil for coke oven gas benzene washing enterprises, correspondingly reduces the regeneration workload after washing oil and benzene, and improves the production efficiency of the enterprises.
Claims (8)
1. The production method of the high-quality wash oil is characterized by comprising the following steps: carrying out primary distillation on the wash oil at a first distillation temperature to separate out naphthalene-rich fraction and mixed oil of naphthalene removal; carrying out secondary distillation on the mixed oil at a second distillation temperature to separate high-quality wash oil fraction and heavy oil, wherein the specification of the high-quality wash oil is as follows: distillate quantity before 230 ℃: none, the distillate yield before 270 ℃ is more than or equal to 90 percent, and the distillate yield before 300 ℃ is more than or equal to 96 percent; the naphthalene content is less than or equal to 5 percent.
2. The method for producing high-quality wash oil as claimed in claim 1, wherein the temperature of the primary distillation is 300-308 ℃.
3. The method for producing high-quality wash oil as claimed in claim 1 or 2, wherein the temperature of the secondary distillation is 310-320 ℃.
4. The coal tar processing method is characterized by comprising the following steps: distilling and separating coal tar to separate washing oil, and carrying out primary distillation on the washing oil at a first distillation temperature to separate naphthalene-rich fraction and naphthalene-removed mixed oil; carrying out secondary distillation on the mixed oil at a second distillation temperature to separate high-quality wash oil fraction and heavy oil, wherein the specification of the high-quality wash oil is as follows: distillate quantity before 230 ℃: none, the distillate yield before 270 ℃ is more than or equal to 90 percent, and the distillate yield before 300 ℃ is more than or equal to 96 percent; the naphthalene content is less than or equal to 5 percent.
5. The coal tar processing method according to claim 4, wherein the coal tar distillation separation comprises the steps of separating a tertiary mixed oil from the coal tar by distillation, washing the tertiary mixed oil, removing phenol, and then carrying out industrial naphthalene distillation to separate the washing oil and the industrial naphthalene;
producing industrial naphthalene by utilizing the naphthalene-rich fraction separated by the primary distillation of the wash oil; and combining the industrial naphthalene separated by the industrial naphthalene distillation and the industrial naphthalene produced by the naphthalene-rich fraction.
6. The coal tar processing method according to claim 4, wherein the coal tar distillation separation comprises distillation separation of anthracene oil from coal tar, and the anthracene oil and the heavy oil separated by the secondary distillation are combined to produce high-quality anthracene oil.
7. The coal tar processing method as set forth in any one of claims 4 to 6, characterized in that the temperature of the primary distillation is 300-308 ℃.
8. The coal tar processing method as set forth in any one of claims 4 to 6, characterized in that the temperature of the secondary distillation is 310-320 ℃.
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| CN202010223495.XA CN111334324A (en) | 2020-03-26 | 2020-03-26 | Production method of high-quality wash oil and coal tar processing method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114133947A (en) * | 2021-11-08 | 2022-03-04 | 中国平煤神马集团平顶山京宝焦化有限公司 | Coal tar distillation device |
Citations (3)
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|---|---|---|---|---|
| CN1078991A (en) * | 1992-10-31 | 1993-12-01 | 鞍山钢铁公司 | From coal tar wash oil, extract the technology of naphthalene cut, methylnaphthalene and industrial acenaphthylene |
| CN101899313A (en) * | 2010-07-29 | 2010-12-01 | 河南宝硕焦油化工有限公司 | Oil-washing deep processing technology of coal tar |
| CN103992199A (en) * | 2014-05-04 | 2014-08-20 | 黄骅市信诺立兴精细化工股份有限公司 | Method for extracting highly pure beta-methylnaphthalene from coal tar wash oil |
-
2020
- 2020-03-26 CN CN202010223495.XA patent/CN111334324A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1078991A (en) * | 1992-10-31 | 1993-12-01 | 鞍山钢铁公司 | From coal tar wash oil, extract the technology of naphthalene cut, methylnaphthalene and industrial acenaphthylene |
| CN101899313A (en) * | 2010-07-29 | 2010-12-01 | 河南宝硕焦油化工有限公司 | Oil-washing deep processing technology of coal tar |
| CN103992199A (en) * | 2014-05-04 | 2014-08-20 | 黄骅市信诺立兴精细化工股份有限公司 | Method for extracting highly pure beta-methylnaphthalene from coal tar wash oil |
Non-Patent Citations (1)
| Title |
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| 何庆香等: "浅析洗油深加工工艺", 《包钢科技》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114133947A (en) * | 2021-11-08 | 2022-03-04 | 中国平煤神马集团平顶山京宝焦化有限公司 | Coal tar distillation device |
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Application publication date: 20200626 |