阅读说明：本技术 煤气化中低温粗酚连续脱色脱臭方法 (Continuous decolorizing and deodorizing method for low-temperature crude phenol in coal gasification ) 是由 张谦 于 2020-05-27 设计创作，主要内容包括：本发明涉及粗酚处理技术领域,尤其涉及煤气化中低温粗酚连续脱色脱臭方法。包括采用碱洗、酸洗、氧化等工艺,去除油中氮化物、硫化物、酸性物质及部分盐类。碱洗、酸洗、氧化等过程在低温﹑低压的条件下进行,利用化学抽提的方式使粗酚与酸液、碱液、氧化剂充分接触,酚中的氮化物、硫化物和酸通过酚/碱、酸、氧化剂界面变成盐存在于酸液和碱液中,增加粗酚精制过程中及产品的稳定性、抗氧化能力,从而使得粗酚分离后的产品苯酚、邻甲酚、间对甲酚、二甲酚成品质量大幅度的提高,保证了产品质量。满足了用户要求及市场需求,可以完全替代进口。(The invention relates to the technical field of crude phenol treatment, in particular to a continuous decoloring and deodorizing method for low-temperature crude phenol in coal gasification. The method comprises the steps of removing nitride, sulfide, acidic substances and partial salts in oil by adopting the processes of alkali washing, acid washing, oxidation and the like. The processes of alkali washing, acid washing, oxidation and the like are carried out under the conditions of low temperature and low pressure, the crude phenol is fully contacted with the acid liquor, the alkali liquor and the oxidant by using a chemical extraction mode, and the nitride, the sulfide and the acid in the phenol are converted into salts through the interfaces of the phenol/alkali, the acid and the oxidant to be present in the acid liquor and the alkali liquor, so that the stability and the oxidation resistance of the crude phenol refining process and products are improved, the quality of finished products of phenol, o-cresol, m-p-cresol and xylenol after the crude phenol is separated is greatly improved, and the quality of the products is ensured. Meets the requirements of users and the market demand, and can completely replace the import.)

1. The continuous decolorizing and deodorizing method of low-temperature crude phenol in coal gasification is characterized in that: comprises the following steps

(1) Carrying out chromatographic inspection on crude phenol to detect whether organic acid is contained in the crude phenol, then introducing untreated crude phenol into an alkali liquid mixer (1), simultaneously mixing a solid alkali solution in an alkali liquid storage tank (2), introducing the solid alkali solution in the alkali liquid storage tank (2) into the alkali liquid mixer (1), introducing the solid alkali solution which is 0.5-1.5% of the amount of the crude phenol when the crude phenol does not contain the organic acid, introducing the solid alkali solution which is 0.5-2.5% of the amount of the crude phenol when the crude phenol contains the organic acid, mixing the solid alkali solution with the crude phenol, introducing the mixture into an alkali liquid settling tank (3), introducing the mixture into the alkali liquid settling tank (3), controlling the temperature of the alkali liquid settling tank (3) to be 40-60 ℃, controlling the pressure of the alkali liquid settling tank (3) to be 0.1-0.3 kPa, and discharging waste liquid from the bottom of the alkali liquid settling tank;

(2) introducing the crude phenol treated in the first step into an oxidant mixer (4), configuring hydrogen peroxide with the concentration of 20-30% in a hydrogen peroxide storage tank (5), introducing the hydrogen peroxide into the oxidant mixer (4) to be 1% -3% of the amount of the crude phenol, introducing the crude phenol mixed in the oxidant mixer (4) into an oxidant settling tank (6), controlling the temperature of the oxidant settling tank (6) to be 50-60 ℃, controlling the pressure of the oxidant settling tank (6) to be 0.5-1 kPa, and discharging waste liquid at the bottom of the oxidant settling tank (6);

(3) introducing the crude phenol treated in the second step into an acid washing mixer (7), introducing an acid washing solution in an acid washing storage tank (8) into the acid washing mixer (7) according to the same dosage of the solid alkali solution introduced in the first step, introducing the crude phenol and the acid washing solution into an acid washing settling tank (9), wherein the temperature of the acid washing settling tank (9) is 60-70 ℃, the pressure of an oxidant settling tank (6) is 0.1-0.5 kPa, and discharging waste liquid at the bottom of the acid washing settling tank (9);

(4) and (2) introducing the crude phenol treated in the third step into a decoloring and deodorizing mixer (10), introducing a diluted acid solution in a diluted acid storage tank (11) into the decoloring and deodorizing mixer (10) according to 0.5-2% of the amount of the crude phenol, introducing the mixed crude phenol and the diluted acid solution into a decoloring and deodorizing settling tank (12), wherein the temperature of the decoloring and deodorizing settling tank (12) is 60-70 ℃, the pressure of the decoloring and deodorizing settling tank (12) is 0.1-0.5 kPa, discharging waste liquid at the bottom of the decoloring and deodorizing settling tank (12), and introducing the treated crude phenol into other equipment for subsequent operation.

2. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: the alkali liquor mixer (1), the oxidant mixer (4), the acid washing mixer (7) and the decoloring and deodorizing mixer (10) adopt a Venturi pipeline mixer, and the pressure in the Venturi pipeline mixer is 0.5kPa-1 kPa.

3. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: in the step one, the organic acid is at least one of butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid and pelargonic acid.

4. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: in the first step, the solid alkali solution is a solution which is dissolved into 30% by water with at least one of sodium carbonate, sodium hydroxide and sodium bicarbonate.

5. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: the acid washing solution in the third step is one of concentrated phosphoric acid solution, concentrated sulfuric acid solution and concentrated hydrochloric acid solution.

6. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: the dilute acid solution in the fourth step is one of dilute phosphoric acid, dilute sulfuric acid and dilute hydrochloric acid.

7. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: the alkali liquor settling tank (3), the oxidant settling tank (6), the acid washing settling tank (9) and the decoloration and deodorization settling tank (12) are made of SUS304 stainless steel.

8. The coal gasification medium-low temperature crude phenol continuous decoloration and deodorization method according to claim 1, which is characterized in that: step one, step two, step three, step four, for the uninterrupted operation, need uninterrupted make-up to add solid-state alkali solution, hydrogen peroxide, pickling solution, dilute acid solution in the uninterrupted operation process.

Technical Field

The invention relates to the technical field of crude phenol treatment, in particular to a continuous decoloring and deodorizing method for low-temperature crude phenol in coal gasification.

Background

Phenol, o-cresol, m-cresol and xylenol are basic products, are widely applied to the fields of pesticides, medicines, spices, dyes, antioxidants, polymerization inhibitors, ultraviolet absorbers, fuel additives, rubber auxiliaries, coatings, feed additives and synthetic materials, are domestic and more delicate fine chemical products, stimulate and promote the consumption and the demand of phenol products in China along with the continuous development of downstream fine chemical products, and meanwhile, the phenol quality is gradually required to be improved, the types of fine products, especially the o-cresol and the m-cresol are seriously insufficient in supply, and a considerable amount of phenol is required to be imported every year to meet the domestic market demand.

Phenol, also known as carbolic acid, is an important basic organic chemical raw material. Can be used for preparing organic chemical products such as bisphenol A, salicylic acid, picric acid, pentachlorophenol, adipic acid, caprolactam, alkylphenol, acetacetoxyethylaniline and the like; in the plastics industry for the manufacture of epoxy resins, phenolic resins, polycarbonates, and the like; in the dye industry for the manufacture of direct dark green, sulphur blue, basic blue lotus, oil-soluble blue lotus, scarlet acid, p-aminophenol, etc.; in the pharmaceutical industry, it is used for the production of aspirin, chloroquine, phenolphthalein, phenolacetic acid, etc., and is also a raw material for detergents, perfumes, agricultural chemicals, etc. In addition, it can be used as solvent, experimental reagent and disinfectant.

The o-cresol is used for producing pesticide herbicide 2-methyl-4-chloro, plasticizer for plastic processing, plasticizer and preservative for viscose fiber and the like, and can also be used for producing o-hydroxybenzaldehyde and o-hydroxybenzoic acid, the o-hydroxybenzaldehyde can be used for synthesizing spice vanillin, and the o-hydroxybenzoic acid is mainly used for producing acid medium bleaching blue B; phenolic resins prepared from o-cresol and formaldehyde are useful as curing agents for epoxy mold compounds in electronic components, particularly computer components; the o-cresol can also be used for producing an antioxidant, a polymerization inhibitor and the like.

The meta-paracresol is an important raw material of an oil-soluble film color former, is also a raw material of high-efficiency low-toxicity pesticides such as fenitrothion, fenthion and metolcarb, and can be used for preparing resin, a plasticizer, spice and the like.

The xylenol can be used for preparing xylenol resin, and is also a raw material for preparing dyes, pesticide, wood preservatives and spices.

The crude phenol is mainly extracted from coal tar, is a byproduct of a coking plant of a matching production plant of a steel plant, and has extremely low yield. China's natural extraction cresol production enterprises mainly comprise Shanghai Bao steel coking plants, Anjian steel coking plants, Nanjing Meishan coking plants, Benxi coking plants, Chongqing organic chemical plants, Shanghai coking plants, famous petrochemicals and the like, the annual output of a large coking plant is about 2000-3000 tons due to process limitation, along with the daily maturity of a gas technology, the processing technology of producing low-temperature coal tar by a German Luqi gasifier is introduced in China successively in recent years, the output of the coal tar is greatly improved, correspondingly, the output of crude phenol is also improved to 7% -8% from the past 0.4%, and the quality of the crude phenol is greatly reduced and the proportion of non-phenolic compounds in the crude phenol is greatly increased due to different production processes.

The high-temperature crude phenol is extracted from high-temperature coal tar, has stable property, less impurities, less phenol content and high meta-position content, and accords with the production of downstream products. The product produced by low-temperature crude phenol in gasification is easy to oxidize, has more impurities and has stronger smell.

The low-temperature crude phenol in gasification contains more substances, more sulfides, nitrides and organic acids, the processed product is easy to oxidize and smells smelly, the produced product cannot be massively used for downstream products, the quality of the downstream products is seriously influenced in the using process, and the using range is reduced.

The content of sulfide, nitride and organic acid in the product is too high, which seriously affects the product quality, but the national standard does not stipulate, so the product quality of the medium-low temperature crude phenol also meets the national standard, but can not be approved by users, and the sale channel is not smooth.

Therefore, treatments such as desulfurization, denitrification, decolorization, deodorization, and organic acid removal are required for the gasification of crude phenol on the market at present.

Disclosure of Invention

The invention aims to solve the technical problem and provides a continuous decolorizing and deodorizing method for low-temperature crude phenol in coal gasification, aiming at the technical defects, wherein the method is used for removing nitrides, sulfides, acidic substances and partial salts in oil by adopting the processes of alkali washing, acid washing, oxidation and the like. The processes of alkali washing, acid washing, oxidation and the like are carried out under the conditions of low temperature and low pressure, the crude phenol is fully contacted with the acid liquor, the alkali liquor and the oxidant by using a chemical extraction mode, and the nitride, the sulfide and the acid in the phenol are converted into salts through the interfaces of the phenol/alkali, the acid and the oxidant to be present in the acid liquor and the alkali liquor, so that the stability and the oxidation resistance of the crude phenol refining process and products are improved, the quality of finished products of phenol, o-cresol, m-p-cresol and xylenol after the crude phenol is separated is greatly improved, and the quality of the products is ensured. Meets the requirements of users and the market demand, and can completely replace the import.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows: comprises the following steps

(1) Carrying out chromatographic inspection on crude phenol to detect whether organic acid is contained in the crude phenol, then introducing untreated crude phenol into an alkali liquid mixer, simultaneously mixing a solid alkali solution in an alkali liquid storage tank, introducing the solid alkali solution in the alkali liquid storage tank into the alkali liquid mixer, introducing the solid alkali solution into the alkali liquid mixer when no organic acid exists in the crude phenol, wherein the amount of the introduced solid alkali solution is 0.5-1.5% of the amount of the crude phenol, introducing the solid alkali solution into the alkali liquid settling tank when the organic acid exists in the crude phenol, mixing the solid alkali solution with the crude phenol, introducing the mixture into the alkali liquid settling tank, controlling the temperature of the alkali liquid settling tank to be 40-60 ℃, controlling the pressure of the alkali liquid settling tank to be 0.1-0.3 kPa, and discharging waste liquid from the bottom of the alkali liquid settling tank;

(2) introducing the crude phenol treated in the first step into an oxidant mixer, configuring hydrogen peroxide with the concentration of 20-30% in a hydrogen peroxide storage tank, introducing the hydrogen peroxide into the oxidant mixer to be 1% -3% of the crude phenol, introducing the crude phenol mixed in the oxidant mixer into an oxidant settling tank, wherein the temperature of the oxidant settling tank is 50-60 ℃, the pressure of the oxidant settling tank is 0.5-1 kPa, and discharging waste liquid at the bottom of the oxidant settling tank;

(3) introducing the crude phenol treated in the step two into an acid washing mixer, introducing an acid washing solution in an acid washing storage tank into the acid washing mixer according to the same dosage of the solid alkali solution introduction amount in the step one, then introducing the crude phenol and the acid washing solution into an acid washing settling tank together, wherein the temperature of the acid washing settling tank is 60-70 ℃, the pressure of an oxidant settling tank is 0.1-0.5 kPa, and discharging waste liquid at the bottom of the acid washing settling tank;

(4) and (3) introducing the crude phenol treated in the third step into a decoloring and deodorizing mixer, introducing a diluted acid solution in a diluted acid storage tank into the decoloring and deodorizing mixer according to 0.5-2% of the amount of the crude phenol, introducing the mixed crude phenol and the diluted acid solution into a decoloring and deodorizing settling tank, wherein the temperature of the decoloring and deodorizing settling tank is 60-70 ℃, the pressure of the decoloring and deodorizing settling tank is 0.1-0.5 kPa, discharging waste liquid at the bottom of the decoloring and deodorizing settling tank, and introducing the treated crude phenol into other equipment for subsequent operation.

Further optimizing the technical scheme, the alkali liquor mixer, the oxidant mixer, the acid washing mixer, the decoloring mixer and the deodorizing mixer all adopt a Venturi pipeline mixer, and the pressure in the Venturi pipeline mixer is 0.5kPa-1 kPa.

Further optimizing the technical scheme, in the step one, the organic acid is at least one of butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid and nonanoic acid.

The technical scheme is further optimized, and in the step one, the solid alkali solution is a solution which is dissolved into 30% by water and at least one of sodium carbonate, sodium hydroxide and sodium bicarbonate.

Further optimizing the technical scheme, the acid washing solution in the third step is one of concentrated phosphoric acid solution, concentrated sulfuric acid solution and concentrated hydrochloric acid solution.

Further optimizing the technical scheme, the dilute acid solution in the step four is one of dilute phosphoric acid, dilute sulfuric acid and dilute hydrochloric acid.

Further optimizes the technical proposal that the alkali liquor settling tank, the oxidant settling tank, the acid washing settling tank, the decoloration and deodorization settling tank are made of SUS304 stainless steel.

The technical scheme is further optimized, wherein the steps I, II, III and IV are continuous uninterrupted operation, and solid-state alkali solution, hydrogen peroxide, pickling solution and dilute acid solution are required to be continuously supplemented and added in the uninterrupted operation process.

Compared with the prior art, the invention has the following advantages:

1. the dosage of the solid alkali can be adjusted according to the result of the chromatography for detecting that the crude phenol contains the organic acid, thereby ensuring the full reaction;

2. in the deoxidation and deodorization processes, under the action of a strong oxidant, organic matters, mercaptan and the like in the crude phenol are promoted to react with oxygen to be converted into disulfide, so that the odor in the crude phenol is removed, and the generated disulfide is still remained in the phenol;

3. a small amount of sodium salt is generated in the processes of alkali washing, oxidation and deodorization of the crude phenol, and in order to ensure the yield in the processing process of the crude phenol and effectively reduce the loss, the sodium salt generated in the pretreatment is converted into the crude phenol by acid washing;

4. the crude phenol and the dilute acid solution are introduced into a decoloring and deodorizing settling tank to react, so that nitrogen oxides in the crude phenol are removed, the antioxidant capacity of the crude phenol product is ensured, and the odor is eliminated.

Drawings

FIG. 1 is a schematic flow diagram of a continuous decolorizing and deodorizing method of low-temperature crude phenol in coal gasification.

In the figure: 1. an alkali liquor mixer; 2. an alkali liquor storage tank; 3. an alkali liquor settling tank; 4. an oxidant mixer; 5. a hydrogen peroxide storage tank; 6. an oxidant settling tank; 7. an acid washing mixer; 8. pickling a storage tank; 9. an acid washing settling tank; 10. a decoloring and deodorizing mixer; 11. a dilute acid storage tank; 12. and (5) decoloring and deodorizing a settling tank.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.