CN111186975A - Ultrasonic oil stain treatment process - Google Patents
Ultrasonic oil stain treatment process Download PDFInfo
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- CN111186975A CN111186975A CN202010164176.6A CN202010164176A CN111186975A CN 111186975 A CN111186975 A CN 111186975A CN 202010164176 A CN202010164176 A CN 202010164176A CN 111186975 A CN111186975 A CN 111186975A
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- powder
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- sludge
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/121—Treatment of sludge; Devices therefor by de-watering, drying or thickening by mechanical de-watering
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/14—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents
- C02F11/147—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents using organic substances
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/15—Treatment of sludge; Devices therefor by de-watering, drying or thickening by treatment with electric, magnetic or electromagnetic fields; by treatment with ultrasonic waves
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Water Supply & Treatment (AREA)
- Hydrology & Water Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Treatment Of Sludge (AREA)
Abstract
The invention relates to an ultrasonic oil stain treatment process, which comprises the following steps: a first mixing step, namely uniformly stirring the oily sludge and the foamed polymer powder to obtain a first polymer sludge mixture; a squeezing separation step, namely placing the first polymer sludge mixture into a squeezer, squeezing out liquid in the first polymer sludge mixture, and separating out oil-water mixed liquid to obtain a squeezed mixture; and a three-phase separation step, namely placing the obtained mixture in a container, adding water, carrying out ultrasonic treatment, standing, layering, and sequentially forming a polymer powder layer, an oil stain layer, a water layer and a mud layer from top to bottom. The invention greatly improves the oil absorption rate after repeated use in an ultrasonic mode. The ultrasonic wave can be matched with the nano particles, so that the adsorption of oil sludge and oil residues on the surface of the polymer powder is reduced, and the separation efficiency is improved.
Description
Technical Field
The invention relates to an ultrasonic oil stain treatment process.
Background
The refining enterprises generate a large amount of oily sludge in the petroleum refining and wastewater treatment processes, and the oily sludge mainly comes from an oil separation tank, a flotation tank, residual activated sludge, a crude oil dehydration tank, an oil storage tank, a sump oil tank and the like. The components of the sludge are complex, the sludge belongs to a stable multiphase system, the mixture is sufficient, the viscosity is high, the solid phase is difficult to completely settle, and the oily sludge is difficult to treat. At present, in the petrochemical industry of China, about 80 ten thousand tons of oily sludge are generated each year on average. Along with the continuous expansion of the scale of the production devices of enterprises, the corresponding total amount and types of waste residue discharge are gradually increased, so that the total amount of pollution discharge and pollution treatment cost of the enterprises also show a rising trend. In recent years, with the increasing requirements of the national environmental protection regulation standard, the environmental protection law enforcement is increased, and the pollution control and resource utilization of the solid waste generated in the production process become difficult problems in the petroleum and petroleum processing industry. The newly revised 'environmental protection and control law of solid waste pollution' puts forward more strict requirements on the prevention and control of the solid waste. The treatment and utilization of solid wastes have been listed as important work contents for building an economical society.
With the development of national economy and the attention on environmental protection, more and more institutions develop the research on the treatment of oily sludge. However, most of the technologies have difficulty in popularization and application to form industrial production due to high treatment cost, long process flow, complex operation, non-ideal treatment effect or other reasons in many aspects. At present, most of oily sludge is treated in an open air stacking or landfill mode, the sludge generally contains hydrocarbons, benzene series, phenols, anthracenes and other substances, and is accompanied by malodor and toxicity, if the sludge is directly contacted with the natural environment, soil, water and vegetation are greatly polluted, and petroleum resources are wasted.
CN1488591A proposes a method for treating oily sludge, which comprises mechanically dewatering oily sludge, mixing with extractant, preheating, homogenizing, thermally extracting, dewatering, separating solid and liquid, introducing the liquid phase into a coking device, and using the solid phase as fuel. The technology needs to preheat materials in the extraction process, the preheating temperature is 50-100 ℃, the operation temperature in the extraction process is 100-150 ℃, and the energy consumption is large; the oily sludge contains too much water, the extraction is not thorough, and the residue after extraction is dried and then needs to be burnt to achieve the harmless effect.
CN1526797A proposes an extraction method of oily sludge, which selects light coal tar (boiling point of 45-90 ℃ at normal pressure) as an extracting agent, petroleum ether, light oil or C5, and separates water, oil and sludge in the oily sludge by utilizing the dissolving effect of a solvent on fuel oil in the oily sludge. However, the extraction process conditions of the technology are that the extraction temperature is 45-55 ℃, the energy consumption in the extraction process is high, the oily sludge is not deeply dehydrated before extraction, and the oil extraction of the oily sludge is not easy to be thorough after extraction.
CN1765781A proposes a method for treating oily sludge, which adopts the mixing of an extracting agent and the oily sludge, the extraction, evaporation, dehydration treatment and solid-liquid separation, and is characterized in that the method is a multi-effect multi-stage or single-effect multi-stage extraction and evaporation system, and the operating conditions of the multi-effect multi-stage extraction and evaporation system are as follows: the first stage of the method adopts normal pressure, the temperature is 95-115 ℃, the pressure of the last stage is 0.01-0.60 MPa, and the temperature is 125-175 ℃. The technology does not carry out deep dehydration treatment on the oily sludge before extraction, the moisture in the oily sludge is too much in the process, the extraction is not thorough, the content of organic matters in the separated solid phase is high, the materials need to be heated in the extraction process, multi-stage extraction is needed, the process flow is long, the number of equipment is large, the equipment investment is large, and the energy consumption is large.
CN101633574A and CN101362979A propose a method for treating oil-containing sludge, in which the oil-containing sludge is subjected to quenching and pressing filtration, and then mixed with coal to be used as fuel, and the oil in the oil-containing sludge cannot be recycled.
CN101343137A proposes a method for treating oil-containing sludge, which comprises subjecting oil-containing sludge to thermal refining, dewatering, drying, etc., and then incinerating. The oil-containing sludge drying process has high energy consumption, and is easy to generate foul tail gas and generate new pollution.
CN103693833A proposes a method for treating oily sludge, comprising the following steps: firstly, mechanically dehydrating the oily sludge to reduce the water content of the oily sludge to 50-90%, then mixing the mechanically dehydrated oily sludge and sand grains with the grain diameter of 20-200 mu m according to the mass ratio of 1: 0.05-0.3, uniformly stirring, then sending the mixture into a squeezing device for squeezing, mixing a mud cake generated after squeezing with an extracting agent, uniformly stirring for extraction, sending the mixed material into a solid-liquid separator after extraction is finished, directly refining separated liquid, and drying separated solid residues to be treated as solid wastes.
In order to solve the above problems, the applicant has filed a patent of a treatment process, which specifically includes: a first mixing step, namely uniformly stirring the oily sludge and the foamed polymer powder to obtain a first polymer sludge mixture; a squeezing separation step, namely placing the first polymer sludge mixture into a squeezer, squeezing out liquid in the first polymer sludge mixture, and separating out oil-water mixed liquid to obtain a squeezed mixture; and a three-phase separation step, namely placing the obtained mixture in a container, adding water, and layering, wherein the upper layer is a polymer powder oil stain layer, the middle layer is a water layer, and the lower layer is a mud layer.
However, the recycling rate of the foamed polymer powder obtained by the above process is low, and the foamed polymer powder needs to be completely discarded after 2 uses.
Disclosure of Invention
In order to solve the technical problem, the invention provides an ultrasonic oil stain treatment process, which comprises the following steps:
a first mixing step, namely uniformly stirring the oily sludge and the foamed polymer powder to obtain a first polymer sludge mixture;
a squeezing separation step, namely placing the first polymer sludge mixture into a squeezer, squeezing out liquid in the first polymer sludge mixture, and separating out oil-water mixed liquid to obtain a squeezed mixture;
a three-phase separation step, namely placing the obtained mixture in a container, adding water, carrying out ultrasonic treatment, standing, layering, and sequentially forming a polymer powder layer, an oil stain layer, a water layer and a mud layer from top to bottom;
the foamed polymer powder is obtained by crushing a foamed polymer into powder, the foamed polymer is formed by foaming 100 parts by weight of the polymer and 20-30 parts by weight of an inert inorganic powder, the foam diameter of the foamed polymer is 150-350 microns, and the average particle diameter of the polymer powder is 100-600 microns.
The foamed plastic is semi-rigid foamed plastic.
The foaming polymer powder is selected from one or more of foaming polyethylene powder, foaming polypropylene powder, foaming styrene powder, foaming ABS powder, foaming polyurethane powder, foaming polyacrylic acid powder and foaming rubber powder.
The inert inorganic powder is selected from one or more of metal powder, silicon dioxide powder and alumina powder.
The particle size of the inert inorganic powder is 10-200 nanometers.
The frequency of the ultrasonic wave is 20-40 kilohertz.
The water content of the oily sludge is 10-90%.
The invention greatly improves the oil absorption rate after repeated use in an ultrasonic mode. The ultrasonic wave can be matched with the nano particles, so that the adsorption of oil sludge and oil residues on the surface of the polymer powder is reduced, and the separation efficiency is improved.
The above-described and other features, aspects, and advantages of the present application will become more apparent with reference to the following detailed description.
Detailed Description
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.
The invention provides an ultrasonic oil stain treatment process, which comprises the following steps:
a first mixing step, namely uniformly stirring the oily sludge and the foamed polymer powder to obtain a first polymer sludge mixture;
a squeezing separation step, namely placing the first polymer sludge mixture into a squeezer, squeezing out liquid in the first polymer sludge mixture, and separating out oil-water mixed liquid to obtain a squeezed mixture;
a three-phase separation step, namely placing the obtained mixture in a container, adding water, carrying out ultrasonic treatment, standing, layering, and sequentially forming a polymer powder layer, an oil stain layer, a water layer and a mud layer from top to bottom;
the expanded polymer powder is obtained by pulverizing an expanded polymer, which is expanded from 100 parts by weight of a polymer and 20 to 30 parts by weight of an inert inorganic powder, to a powder, and has a cell diameter of 150-350 μm and an average particle diameter of 200-800. mu.m (measured by a laser light scattering method).
The foamed plastic is semi-rigid foamed plastic.
The foaming polymer powder is selected from one or more of foaming polyethylene powder, foaming polypropylene powder, foaming styrene powder, foaming ABS powder, foaming polyurethane powder, foaming polyacrylic acid powder and foaming rubber powder.
The inert inorganic powder is selected from one or more of metal powder, silicon dioxide powder and alumina powder.
The particle size of the inert inorganic powder is 10-200 nanometers.
The frequency of the ultrasonic wave is 20-40 kilohertz.
The water content of the oily sludge is 10-90%.
Hereinafter, the present invention will be described in more detail by way of examples, but it should be understood that these examples are merely illustrative and not restrictive. The starting materials used are all commercially available, unless otherwise stated.
The preparation process of the polymer powder comprises the following steps:
70 parts by weight of polyoxyethylene oxypropylene ether polyol with propylene glycol as initiator
30 parts by weight of polyoxyethylene oxypropylene ether polyol with glycerin as initiator
1 part by weight of diethanolamine
2.4 parts by weight of water
0.3 part by weight of tetramethylhexamethylenediamine
0.1 part by weight of triethylene diamine
49.6 parts by weight of polymeric MDI
30 parts by weight of nano silicon dioxide
The mold temperature was 40 degrees celsius. Vulcanization time 4 minutes, gel time 96 seconds, rise time 163 seconds.
The resulting semi-rigid foamed plastic had a foam density of 151kg/m3, a final Shore C hardness of 39, a foam diameter of 200 and 320. mu.m.
Wherein the polymeric MDI is MR-200 of NPU company of Japan, the hydroxyl value of polyoxyethylene propylene oxide ether polyol taking propylene glycol as initiator is 28, the molecular weight is 4000, and the content of ethylene oxide is 20%. The polyoxyethylene oxypropylene ether polyol with glycerin as initiator has hydroxyl value of 34, molecular weight of 5000 and ethylene oxide content of 18%.
The nano-silica is AEROSIL R974, purchased from Degussa, and is hydrophobic nano-fumed silica, and the parameters are as follows:
the rest are all commercial products.
300g of oil sludge (water content 69.4%, oil content 27.2%, solid content 3.4%) was added to 130g of foamed polyurethane powder (polymer powder obtained by the above preparation, average particle size is shown later) and stirred uniformly (10 min), the mixture was placed in a press, oil and water were squeezed out, and the remaining part was placed in a special separator for ultrasonic separation. Separating to obtain the uppermost layer of powder, filtering the water phase with modified adsorption powder (COD less than 30 mg/L), and making sludge harmless. Standing the recovered oil water for 30min to separate the oil water layer and recover the oil product.
And (3) repeatedly utilizing after centrifugal drying: the uppermost layer of the separated powder was dried, and the polymer powder was replaced with 130g of the polymer powder (loss, the amount of sludge used was reduced at the same ratio), and the sludge was treated repeatedly (water content: 69.4%, oil content: 27.2%, solid content: 3.4%). The particle size of the polymer powder, the recovery of the recovered oil obtained in 1 and 4 and 8 treatments are shown in the following table:
it can be seen that the invention adopts the mode of ultrasonic treatment by controlling the particle size of the polymer powder and adding the nano silicon dioxide. Through comparison, the recovery rate is reduced to 45.1 percent and 35.4 percent respectively after 8 times of use by using the ordinary micron-grade silicon dioxide instead of the nano silicon dioxide or not using the nano silicon dioxide. And the recovery rate is reduced to 25.1 percent after 8 times of use without adopting ultrasonic treatment. It can be seen that the invention greatly improves the oil absorption rate after being used for many times by means of ultrasonic waves. The ultrasonic wave can be matched with the nano particles, so that the adsorption of oil sludge and oil residues on the surface of the polymer powder is reduced, and the separation efficiency is improved.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. All equivalent changes and modifications made according to the disclosure of the present invention are covered by the scope of the claims of the present invention.
Claims (7)
1. An ultrasonic oil stain treatment process is characterized by comprising the following steps:
a first mixing step, namely uniformly stirring the oily sludge and the foamed polymer powder to obtain a first polymer sludge mixture;
a squeezing separation step, namely placing the first polymer sludge mixture into a squeezer, squeezing out liquid in the first polymer sludge mixture, and separating out oil-water mixed liquid to obtain a squeezed mixture;
a three-phase separation step, namely placing the obtained mixture in a container, adding water, carrying out ultrasonic treatment, standing, layering, and sequentially forming a polymer powder layer, an oil stain layer, a water layer and a mud layer from top to bottom;
the foamed polymer powder is obtained by crushing a foamed polymer into powder, the foamed polymer is formed by foaming 100 parts by weight of the polymer and 20-30 parts by weight of an inert inorganic powder, the foam diameter of the foamed polymer is 150-350 microns, and the average particle diameter of the polymer powder is 100-600 microns.
2. The ultrasonic oil stain treatment process according to claim 1, wherein the foamed plastic is semi-rigid foamed plastic.
3. The ultrasonic oil stain treatment process according to claim 1, wherein the foamed polymer powder is selected from one or more of foamed polyethylene powder, foamed polypropylene powder, foamed styrene powder, foamed ABS powder, foamed polyurethane powder, foamed polyacrylic acid powder and foamed rubber powder.
4. The ultrasonic oil stain treatment process according to claim 1, wherein the inert inorganic powder is one or more selected from metal powder, silicon dioxide powder and aluminum oxide powder.
5. The ultrasonic oil stain treatment process according to claim 1, wherein the particle size of the inert inorganic powder is 10-200 nm.
6. The ultrasonic oil stain treatment process according to claim 1, wherein the frequency of the ultrasonic wave is 20-40 kilohertz.
7. The ultrasonic oil stain treatment process according to claim 1, wherein the water content of the oil-containing sludge is 10-90%.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010164176.6A CN111186975A (en) | 2020-03-11 | 2020-03-11 | Ultrasonic oil stain treatment process |
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| CN202010164176.6A CN111186975A (en) | 2020-03-11 | 2020-03-11 | Ultrasonic oil stain treatment process |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006289180A (en) * | 2005-04-06 | 2006-10-26 | Matsushita Electric Ind Co Ltd | Sludge treatment apparatus |
| US20150360986A1 (en) * | 2014-06-17 | 2015-12-17 | Nippon Zoki Pharmaceutical Co., Ltd. | Method and system for sludge treatment |
| CN108203218A (en) * | 2018-01-05 | 2018-06-26 | 金碳环境科技（天津）有限公司 | A kind of harmless treatment process of oily sludge |
| CN108516755A (en) * | 2018-07-06 | 2018-09-11 | 四川建筑职业技术学院 | A kind of inorganic polymer expanded material and preparation method thereof prepared using sludge |
| CN208136059U (en) * | 2018-02-15 | 2018-11-23 | 金碳环境科技（天津）有限公司 | A kind of oily sludge dregs of fat separation harmless treatment drain oil recovery equipment |
| CN110054393A (en) * | 2019-04-12 | 2019-07-26 | 天津大学 | A kind of processing method of oily sludge |
| CN110436682A (en) * | 2019-07-06 | 2019-11-12 | 中海石油（中国）有限公司天津分公司 | A kind of offshore oilfield returns drain advanced treatment process |
| CN110451749A (en) * | 2019-09-17 | 2019-11-15 | 山东大学 | A kind of intensifying method of oily sludge ultrasonic dehydration and system and technique |
-
2020
- 2020-03-11 CN CN202010164176.6A patent/CN111186975A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006289180A (en) * | 2005-04-06 | 2006-10-26 | Matsushita Electric Ind Co Ltd | Sludge treatment apparatus |
| US20150360986A1 (en) * | 2014-06-17 | 2015-12-17 | Nippon Zoki Pharmaceutical Co., Ltd. | Method and system for sludge treatment |
| CN108203218A (en) * | 2018-01-05 | 2018-06-26 | 金碳环境科技（天津）有限公司 | A kind of harmless treatment process of oily sludge |
| CN208136059U (en) * | 2018-02-15 | 2018-11-23 | 金碳环境科技（天津）有限公司 | A kind of oily sludge dregs of fat separation harmless treatment drain oil recovery equipment |
| CN108516755A (en) * | 2018-07-06 | 2018-09-11 | 四川建筑职业技术学院 | A kind of inorganic polymer expanded material and preparation method thereof prepared using sludge |
| CN110054393A (en) * | 2019-04-12 | 2019-07-26 | 天津大学 | A kind of processing method of oily sludge |
| CN110436682A (en) * | 2019-07-06 | 2019-11-12 | 中海石油（中国）有限公司天津分公司 | A kind of offshore oilfield returns drain advanced treatment process |
| CN110451749A (en) * | 2019-09-17 | 2019-11-15 | 山东大学 | A kind of intensifying method of oily sludge ultrasonic dehydration and system and technique |
Non-Patent Citations (2)
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