Three-phase separation integrated treatment system for oily sludge

Abstract

The utility model belongs to the technical field of petrochemical engineering, and particularly relates to a three-phase separation integrated treatment system for oily sludge. An oily sludge separation unit in the system is used for dewatering and deoiling conditioned sludge and performing solid-liquid separation by using a plate-and-frame filter press to respectively obtain sludge and filtered liquid; the sludge cleaning unit is used for cleaning and conveying out the separated sludge; the dirty oil treatment unit is used for separating sewage and oil through the filtered liquid receiving unit; the separated sewage reacts with a sewage treatment agent in the sewage treatment unit to form primary sedimentation sewage, and the primary sedimentation sewage is filtered and reused as return water for sludge treatment; the separated sump oil enters a sump oil disposal unit, viscosity reduction components in the sump oil are recycled to serve as an extraction agent and then put into the oily sludge separation unit, and the remaining sump oil returns to an in-station oil collection system or is sold. According to the utility model, three-phase substances of oil, mud and water in the sludge are completely separated at one time, and secondary wastes are not generated.

Description

Technical Field

[0001] The utility model belongs to the technical field of petrochemical industry, and in particular relates to a three-phase separation integrated treatment system for oily sludge. Background Art

[0002] Oily sludge is a waste generated in the production process of oil, gas fields and chemical industries. Since it contains a large amount of mineral oil, direct discharge will seriously pollute the environment. In order to deal with this problem, sludge containing mineral oil has been listed as a hazardous waste, and its discharge has strict requirements. With the continuous advancement of technology, the discharge index of oily sludge in oil and gas fields has been increased from the initial oil content of <2% to the current <0.3%.

[0003] At present, the treatment methods of oily sludge mainly include incineration, pyrolysis, biological treatment, solidification, extraction and chemical heat washing. However, the above methods have the following technical problems:

[0004] 1. Incineration is a treatment method that can completely eliminate oily sludge, but it consumes a lot of energy and cannot recover oil, resulting in a waste of resources.

[0005] 2. Although cracking treatment can consume a lot of energy, the oil content of the treated sludge does not meet the latest standards.

[0006] 3. Biological treatment is a method that takes a long time, is complex to operate, and is greatly affected by climate and environment. It has not yet been widely used.

[0007] 4. Solidification treatment may cause leakage problems, resulting in ground pollution and requiring the occupation of a large amount of land.

[0008] 5. Extraction treatment is a more expensive method.

[0009] 6. At present, the commonly used treatment method in oil fields is chemical hot washing, but it is limited to the deoiling of solid particles and cannot eradicate a large amount of non-particulate impurities and oil and water residues such as colloids, polymers, chemicals, flocs, minerals, etc. in the sludge. Therefore, it has certain limitations.

[0010] Therefore, the existing treatment methods still have problems such as high energy consumption, oil content of sludge after treatment not meeting the latest standards, long treatment time, complex operation, great environmental impact, and possible formation pollution. Summary of the invention

[0011] The utility model aims to provide an integrated three-phase separation treatment system for oily sludge, so that the three-phase substances of oil, mud and water in the sludge can be completely separated at one time without generating secondary waste.

[0012] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0013] An integrated treatment system for three-phase separation of oily sludge, the system comprises an oily sludge separation unit, a sludge cleaning unit, a filtered liquid receiving unit, an oily waste disposal unit and a sewage treatment unit; the oily sludge separation unit is used to dehydrate and deoil the conditioned sludge, and use a plate and frame filter press to perform solid-liquid separation to obtain sludge and filtered liquid respectively; the sludge cleaning unit is used to clean and transport the separated sludge; the oily waste disposal unit separates sewage and oil through the filtered liquid receiving unit; the separated sewage reacts with a sewage treatment agent in the sewage treatment unit to form primary sedimentation sewage, which is then filtered and reused as back-mixing water for sludge treatment; the separated waste oil enters the waste oil disposal unit, and the viscosity-reducing component in the waste oil is recovered and used as an extractant and then fed into the oily sludge separation unit, and the remaining waste oil is returned to the oil collection system in the station or sold.

[0014] As a preferred technical solution, the oily sludge separation unit comprises an oily sludge storage unit, a lifting pump, a sludge conditioning unit and a plate and frame filter press connected in sequence; the sludge stored in the oily sludge storage unit enters the sludge conditioning unit through the lifting pump, the extractant, the sludge conditioning agent and the oily sludge are mixed and reacted under the action of the agitator, and the oily sludge is degelled and demulsified; compressed air pushes the conditioned sludge into the plate and frame filter press of the sludge filter press unit for dehydration and deoiling, thereby realizing solid-liquid separation.

[0015] As a preferred technical solution, the sludge cleaning unit includes a sludge receiving unit, a sludge cleaning machine and a sludge transporting unit; after the sludge after filter pressing enters the sludge cleaning machine, a sludge cleaning agent is added to clean the sludge to obtain clean sludge, which is then transported out through the sludge transporting unit.

[0016] As a preferred technical solution, the filtered liquid receiving unit includes a filtered liquid receiving box and an oil-water separation device; the filtered liquid after pressure filtration enters the filtered liquid receiving box and then enters the oil-water separation device to separate the dirty oil and sewage.

[0017] As a preferred technical solution, the sewage treatment unit includes a cyclone sedimentation tank, a filter and a purified water tank. The separated sewage enters the cyclone sedimentation tank, and sewage treatment agents are added to react, adsorb and purify water in the cyclone sedimentation tank to form primary sedimentation sewage, which then enters the filter to filter and produce purified water before entering the purified water tank.

[0018] The utility model also discloses a production process of the above-mentioned oily sludge three-phase separation integrated treatment system, comprising the following steps:

[0019] S1. Conditioning: The oily sludge is fully mixed and reacted with the extractant and sludge conditioning agent in the sludge conditioning tank to obtain demulsification and gel breaking;

[0020] S2, solid-liquid separation: Compressed air pushes the conditioned sludge into the plate and frame filter press for sludge dehydration, deoiling and solid-liquid separation;

[0021] S3, sludge cleaning: the sludge after filter pressing enters the sludge cleaning device, and sludge cleaning agent is added for cleaning to obtain clean sludge;

[0022] S4, oil-water separation of filtered liquid: The filtered liquid enters the oil-water separator for oil-water separation to obtain sewage and waste oil;

[0023] S5. Waste oil extraction and recovery: The separated waste oil is extracted and recovered in the extractant recovery machine, which puts the recovered extractant back into the sludge conditioning tank. The remaining waste oil is stored in the waste oil recovery tank and returned to the oil collection system in the station or sold;

[0024] S6. Sewage filtration: The separated sewage enters the cyclone sedimentation tank, and sewage treatment chemicals are added to react, adsorb and purify water in the cyclone sedimentation tank to form primary sedimentation sewage, which then enters the filter to filter the primary sedimentation sewage. After the purified water is produced, it enters the purified water tank and can be reused as reintegration water for sludge treatment.

[0025] As a preferred technical solution, the sludge conditioning agent in S1 includes one or more of caustic soda, sodium carbonate, OP-10, NP-2, polyacrylamide, and penetrant, and the addition concentration is 10ppm-1000ppm.

[0026] As a preferred technical solution, the sludge cleaning agent in S3 is a mixture of diesel and acetone.

[0027] As a preferred technical solution, the water content of the clean sludge in S3 is less than 60%, and the oil content is less than 0.3%.

[0028] As a preferred technical solution, the purified water produced in S6 has a water quality of oil content of less than 10 mg / l and suspended solids of less than 10 mg / l.

[0029] Compared with the prior art, the utility model has the following beneficial effects:

[0030] The utility model can treat the oily sludge produced by the oil, gas field and chemical industry and reduce the oil content to below 0.3%, reaching the highest standard for oil and gas field sludge treatment. The treated sludge can be directly used for filling well sites, paving roads, well site construction, etc., saving a lot of oily sludge treatment costs for oil and gas fields.

[0031] The utility model can purify the oil in the sludge and regenerate it into crude oil, with a recovery rate of 98%.

[0032] During the treatment process, the sludge does not need to be heated, which can save a lot of energy; the technology is not affected by the ambient temperature and can be produced all year round, suitable for the treatment of oily sludge in major oil and gas fields across the country;

[0033] It can treat sludge with different oil content, just need to change the concentration and type of the added agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a structural schematic diagram of the three-phase separation integrated treatment system for oily sludge provided by the utility model.

[0035] In the above figure: 1- oily sludge, 2- sludge conditioning agent, 3- conditioned sludge, 4- sludge after filter pressing, 5- liquid phase after filter pressing, 6- clean sludge, 7- filtered liquid, 8- dirty oil, 9- sewage, 10- primary sedimentation sewage, 11- purified water, 12- extraction agent, 13- sewage treatment agent, 14- compressed air, 15- sludge cleaning agent, 16- recovered oil, 101- oily sludge tank, 102- lifting pump, 103- 03-sludge conditioning tank, 104-plate and frame filter press, 201-sludge storage unit after filtration, 202-sludge cleaner, 203-clean sludge storage unit, 204-filtered liquid receiving water tank, 205-oil-water separation unit, 301-dirty oil receiving unit, 302-extractant recovery device, 303-recovered oil storage unit, 304-wastewater treatment sedimentation unit, 305-filter, 306-purified water storage unit. DETAILED DESCRIPTION

[0036] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods.

[0037] like Figure 1 As shown, the utility model discloses an integrated treatment system for three-phase separation of oily sludge, which comprises an oily sludge separation unit, a sludge cleaning unit, a filtered liquid receiving unit, a dirty oil disposal unit and a sewage disposal unit; the oily sludge separation unit is used to dehydrate and deoil the conditioned sludge, perform solid-liquid separation, and obtain sludge and filtered liquid respectively; the sludge cleaning unit is used to clean and transport the separated sludge; the dirty oil disposal unit separates sewage and oil through the filtered liquid receiving unit, and disposes of them separately;

[0038] The oily sludge separation unit comprises an oily sludge storage unit 101, a lifting pump 102, a sludge conditioning unit 103 and the sludge filter press unit 104 which are connected in sequence; the sludge conditioning unit is a sludge conditioning tank, which is used as a reaction place for the oily sludge, the extractant 12 and the sludge conditioning agent 2. The sludge stored in the oily sludge storage unit enters the sludge conditioning unit 103 through the lifting pump, and the extractant 12 and the sludge conditioning agent 2 are added at the same time. Under the action of the agitator, the extractant 12, the sludge conditioning agent 2 and the oily sludge are fully mixed and reacted, and the sludge is de-gelled and de-emulsified; the sludge filter press unit is a plate and frame filter press, which is used for dehydrating and deoiling the conditioned sludge 3 and performing solid-liquid separation; the compressed air 14 pushes the conditioned sludge into the plate and frame filter press to dehydrate and deoil the sludge and perform solid-liquid separation. The sludge conditioning agent comprises one or more of caustic soda, sodium carbonate, OP-10, NP-2, polyacrylamide, and penetrant. The dosing concentration of sludge conditioner is 10ppm-1000ppm. The compressed air pressure is 0.5~12.0 MPa.

[0039] The sludge cleaning unit includes a sludge receiving unit 201, a sludge cleaning machine 202 and a sludge transporting unit 203. After the sludge 4 after the filter press enters the sludge cleaning machine 202, a sludge cleaning agent 15 is added to clean the sludge to obtain clean sludge 6, which is then transported out through the sludge transporting unit 203. The water content of the clean sludge is less than 60%, and the oil content is less than 0.3%. The sludge cleaning agent 15 is a mixture of organic solvents such as diesel and acetone.

[0040] The filtered liquid receiving unit includes a filtered liquid receiving box 204 and an oil-water separator 205; the filtered liquid 7 after pressure filtration enters the filtered liquid receiving box 204 and then enters the oil-water separator 205 to separate the dirty oil and sewage; the oil-water separator 205 is a gravity oil-water separator.

[0041] The waste oil treatment unit comprises a waste oil receiving tank 301, an extractant recovery device 302 and an extractant storage unit 303. The separated waste oil 8 enters the waste oil receiving tank 301 and then enters the extractant recovery device 302 to recover the viscosity reducing components in the waste oil. The extractant recovery device 302 re-injects the extractant 12 into the sludge conditioning unit 103. The remaining waste oil is stored in the extractant storage unit 303 and returned to the oil collection system in the station or sold.

[0042] The sewage treatment unit includes a cyclone sedimentation tank 304, a filter 305 and a purified water tank 306. The separated sewage 9 enters the cyclone sedimentation tank 304, and is added with a sewage treatment agent 13. The sewage 9 reacts, adsorbs, and purifies in the cyclone sedimentation tank 304 to form primary sedimentation sewage 14, and then enters the filter 305. The primary sedimentation sewage 14 is filtered and treated to produce purified water 11, which enters the purified water tank 306. The purified water has a water quality of less than 10 mg / l oil and suspended solids less than 10 mg / l, which meets the standard for reinjection and can be used for reinjection as reinjection water for sludge treatment. The cyclone sedimentation tank 304 is a coagulation sedimentation water treatment device, including a cyclone sedimentation device, an inclined plate sedimentation tank, a high-density sedimentation tank, etc.

[0043] The production process of the above-mentioned integrated treatment system for three-phase separation of oily sludge specifically includes: the oily sludge 1 enters the sludge conditioning tank 103, and the extractant 12 and the sludge conditioning agent 3 are added at the same time. Under the action of the agitator, the extractant 12, the sludge conditioning agent 3 and the oily sludge are fully mixed and reacted in the sludge conditioning tank 103, and the sludge is degelled and demulsified; the compressed air 14 pushes the conditioned sludge 4 into the plate and frame filter press 104 to dehydrate and deoil the sludge and perform solid-liquid separation; after the sludge 6 after filtration enters the sludge cleaner, the sludge cleaning agent 15 is added, and the sludge is cleaned in the sludge cleaner 202 to obtain clean sludge 6, which is transported out through the sludge transport unit 203. The filtered liquid 7 enters the oil-water separator 205 for oil-water separation; the separated dirty oil 8 enters the dirty oil receiving tank 301 and the extractant recovery machine 302, the extractant recovery machine 302 re-adds the extractant 12 to the sludge conditioning tank 103, and the remaining dirty oil is stored in the dirty oil recovery tank 303, returned to the oil collection system in the station or sold; the separated sewage 9 enters the cyclone sedimentation tank 304, and is added with sewage treatment reagents 13, reacts, adsorbs and purifies water in the cyclone sedimentation tank 304 to form primary sedimentation sewage 10, and then enters the filter 305, the primary sedimentation sewage 10 is filtered and treated, and purified water 11 is produced and enters the purified water tank 306. The water quality of the purified water reaches oil content <10mg / l and suspended solids <10mg / l, which meets the reinjection standard and can be reused as reincorporated water for sludge treatment.

[0044] The utility model uses the above three-phase separation integrated treatment system for oily sludge, chemical and mechanical treatment methods to completely separate the oily sludge into qualified clean water, crude oil and mud cake. Both the clean water and crude oil can be reused, and the mud cake can be used for paving roads in well sites, etc. The oily sludge is conditioned and treated, and a plate-and-frame filter press is used for solid-liquid separation. The liquid phase is filtered to become qualified clean water, and the solid phase sludge is then washed to reduce the oil content of the sludge from 2% to below 0.3%, reaching the new standard. Since the sludge does not need to be heated at room temperature, the energy consumption is greatly reduced compared with other treatment technologies, and the conditioning agent can be adjusted according to the properties of the sludge to adapt to the treatment of sludge of different properties.

[0045] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

Claims

1. An integrated three-phase separation treatment system for oily sludge, characterized by: The system includes an oily sludge separation unit, a sludge cleaning unit, a filtered liquid receiving unit, a dirty oil disposal unit and a sewage disposal unit; the oily sludge separation unit is used to dehydrate and deoil the conditioned sludge, and use a plate and frame filter press to perform solid-liquid separation to obtain sludge and filtered liquid respectively; the sludge cleaning unit is used to clean and transport the separated sludge; The waste oil treatment unit separates sewage and oil through the post-filtration liquid receiving unit; the separated sewage reacts with sewage treatment agents in the sewage treatment unit to form primary sedimentation sewage, which is then filtered and reused as remixing water for sludge treatment; the separated waste oil enters the waste oil treatment unit, the viscosity-reducing components in the waste oil are recovered as an extractant and then put into the oil-containing sludge separation unit, and the remaining waste oil is returned to the oil collection system in the station or sold.

2. The three-phase separation integrated treatment system for oily sludge according to claim 1, characterized in that: The oily sludge separation unit comprises an oily sludge storage unit, a lifting pump, a sludge conditioning unit and a plate and frame filter press which are connected in sequence; the sludge stored in the oily sludge storage unit enters the sludge conditioning unit through the lifting pump, the extractant, the sludge conditioning agent and the oily sludge are mixed and reacted under the action of the agitator, and the oily sludge is degelled and demulsified; compressed air pushes the conditioned sludge into the plate and frame filter press of the sludge filter press unit for dehydration and deoiling, thereby realizing solid-liquid separation.

3. The three-phase separation integrated treatment system for oily sludge according to claim 2, characterized in that: The sludge cleaning unit comprises a sludge receiving unit, a sludge cleaning machine and a sludge transporting unit; after the sludge after the filter pressing enters the sludge cleaning machine, a sludge cleaning agent is added to clean the sludge to obtain clean sludge, which is then transported out through the sludge transporting unit.

4. The three-phase separation integrated treatment system for oily sludge according to claim 2, characterized in that: The filtered liquid receiving unit comprises a filtered liquid receiving box and an oil-water separation device; the filtered liquid after pressure filtration enters the filtered liquid receiving box and then enters the oil-water separation device to separate the dirty oil and sewage.

5. The three-phase separation integrated treatment system for oily sludge according to claim 4, characterized in that: The sewage treatment unit includes a cyclone sedimentation tank, a filter and a purified water tank. The separated sewage enters the cyclone sedimentation tank, and sewage treatment agents are added to react, adsorb and purify water in the cyclone sedimentation tank to form primary sedimentation sewage, which then enters the filter to filter and treat the primary sedimentation sewage to produce purified water, which enters the purified water tank.

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