CN101734834A - Method for recovering sandy oil-containing sludge - Google Patents

Method for recovering sandy oil-containing sludge Download PDF

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Publication number
CN101734834A
CN101734834A CN200910113612A CN200910113612A CN101734834A CN 101734834 A CN101734834 A CN 101734834A CN 200910113612 A CN200910113612 A CN 200910113612A CN 200910113612 A CN200910113612 A CN 200910113612A CN 101734834 A CN101734834 A CN 101734834A
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China
Prior art keywords
oil
containing sludge
sandy
extraction solvent
recovering
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Pending
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CN200910113612A
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Chinese (zh)
Inventor
张学鲁
杜文军
杜庆华
刘国良
骆伟
王爱军
赵瑞玉
曾玉群
杨宴宾
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BEIJING GREENFIELD TECHNOLOGY DEVELOPMENT Co Ltd
Xinjiang Oilfield Survey & Design Institute
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BEIJING GREENFIELD TECHNOLOGY DEVELOPMENT Co Ltd
Xinjiang Oilfield Survey & Design Institute
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Application filed by BEIJING GREENFIELD TECHNOLOGY DEVELOPMENT Co Ltd, Xinjiang Oilfield Survey & Design Institute filed Critical BEIJING GREENFIELD TECHNOLOGY DEVELOPMENT Co Ltd
Priority to CN200910113612A priority Critical patent/CN101734834A/en
Publication of CN101734834A publication Critical patent/CN101734834A/en
Pending legal-status Critical Current

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Abstract

The invention belongs to the technical field of sludge treatment of oil fields and relates to a method for recovering sandy oil-containing sludge, which comprises the following steps: fully mixing extracting solvent with the sandy oil-containing sludge of the oil fields in a volume ratio of 0.5:1 at a temperature of between 10 and 80 DEG C to allow oil to dissolve in the extracting solvent to form a structure of three separated layers; then separating an extracting solvent layer, a water layer and a silt layer from one another; and performing distillation of the separated extracting solvent layer at an atmospheric pressure or reduced pressure to acquire oil and the extracting solvent respectively. The method can effectively extract and recover crude oil in the oil-containing sludge, and silt separated out reaches national stacking standards; the solvent can be recycled, and washing water can be sewage of the oil fields and can be recycled by electroflotation without causing secondary pollution, so that the oil and the water in the sandy oil-containing sludge of the oil fields can be recovered, and thus the original discarded resources are fully utilized, and the problem of discharging the sandy oil-containing sludge of the oil fields is solved effectively.

Description

Method for recovering sandy oil-containing sludge
Technical field
The present invention relates to the technical field that oil field sludge is handled, is a kind of method for recovering sandy oil-containing sludge.
Background technology
The source of sump oil mud mainly is the sandy oil-containing sludge that produces in the Oil extraction process, the sandy oil-containing sludge that contains sandy oil-containing sludge and the generation of refinery's Sewage treatment systems of oil field gathering and transportation process generation.These sump oil Fenders contain outside the crude oil, also contain the stratum silt that carries in the extraction liquid, the flco that forms in the sewage treatment process of disposing polluted water in oil station, corrosive pipeline product, heavy metal salt and paraffin, gum asphalt etc. and certain moisture content.
The oily sludge that produces in the Oil extraction process is mainly derived from Ground Processing System, and the oily sludge that produces in the oil extraction-generated waste water treating processes is added flco that water purification agent that sewage purification adds in handling forms etc. and formed oily sludge.
The oil field gathering and transportation process produces oil tank that oily sludge is mainly derived from block station, joint station, slurry tank, sewage jar, oil trap bed mud, oil product storage tank when storing oil product, a small amount of mechanical impurity in the oil product, the grains of sand, earth, heavy metal salt and heavy components such as paraffin and bituminous matter are deposited on tank bottom, form tank bottom oil sludge.The blowdown of slurry tank, secondary settlement jar, well-flushing water withdrawing can also can produce oily sludge in addition.
By analysis these oily sludges form different, usually oil length between 10%~60%, solids 10-60% such as silt, and water 15-60%.Under the situation that petroleum resources growing tension and environmental problem are on the rise, the crude oil in the efficient recovery sump oil mud has not only been saved valuable petroleum resources, and has eliminated environmental pollution.
Relatively the method for processing oily sludge commonly used has at present: solidify and bury, burn hot washing method, solvent extration, chemical demulsification method, solid-liquid isolation method, pyrolysis method etc.But wherein many methods all exist some problems, are not suitable for very much for practical application.Power consumption greatly, easily produces secondary pollution as burning method, the crude resources waste; Biological treatment need last length, and same crude resources also can not get recycling; Chemical demulsification method need add emulsion splitter and heating in addition to the serious oily sludge of emulsification, and aftertreatment is difficult, also produces secondary pollution simultaneously; Solid-liquid isolation method is low for the crude oil recovery rate that contains innage, with serious pollution oily sludge; Pyrolysis method facility investment height.
Solvent extraction is the effective ways that reclaim crude oil, and the body refuse after the extraction more easily reaches the national standard of landfill or stacking,, but and the crude resources of efficient recovery preciousness, thereby draw its people's attention.Patent CN1526797A, the application extraction process reclaims oil fuel from oily sludge, and this patent adopts general extraction tower, when the oily sludge layering is slow, needs the diluted acid of adding 1% to 3% to carry out breakdown of emulsion, can cause the corrosion and the second environmental pollution of equipment.
Summary of the invention
The invention provides a kind of method for recovering sandy oil-containing sludge, it has overcome the deficiency of prior art, solved the emission problem of oil field sandy oil-containing sludge effectively, made the You Heshui in the sandy oil-containing sludge of oil field obtain reclaiming, made the silt particle oil-containing of separating reach national stacking standard.
Realizing of technical scheme of the present invention: a kind of method for recovering sandy oil-containing sludge by following measure, it is characterized in that being undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 0.5: 1 to 10: 1 be 10 ℃ to 80 ℃ following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil, 120 #The mixture of one or more in solvent oil, aromatic hydrocarbons, condensate oil, the sherwood oil.
Below technique scheme is done further to optimize or/and select:
With above-mentioned isolated dirty sand again water embathe.
Above-mentioned isolated dirty sand is embathed with oilfield sewage again.
After washing water after above-mentioned the embathing carry out three phase separation, the water recycling of telling.
Above-mentioned isolated water layer or embathe separation after washing water recirculation after electric floating processing use.
The per-cent of gross weight of pressing the sandy oil-containing sludge in extraction solvent and oil field in the sandy oil-containing sludge in above-mentioned extraction solvent and oil field adds 0.5% to 5% inorganic salt.
Before above-mentioned extraction, earlier fabric, bar, big block in the sandy oil-containing sludge in oil field are screened out.
Extraction plant in above-mentioned extracting operation process adopts dual horizontal axle extraction plant.
The present invention can effectively extract the crude oil that reclaims in the oily sludge, the silt particle oil-containing of separating reaches national stacking standard, solvent is recyclable, washing water can be oilfield sewage, electric floating processing back reusable edible does not cause secondary pollution, makes the You Heshui in the sandy oil-containing sludge of oil field obtain reclaiming, thereby made full use of original depleted resource, solved the emission problem of oil field sandy oil-containing sludge effectively.
Embodiment
The present invention is not subjected to the restriction of following embodiment, can determine concrete embodiment according to technical scheme of the present invention and practical situation.
Below in conjunction with embodiment the present invention is further described:
Embodiment 1, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 0.5: 1 to 10: 1 be 10 ℃ to 80 ℃ following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil, 120 #One of in solvent oil, aromatic hydrocarbons, condensate oil, the sherwood oil or the mixture more than two kinds.
Embodiment 2, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 0.5: 1 be 10 ℃ of following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil or 120 #Solvent oil.
Embodiment 3, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 1: 1 be 50 ℃ of following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil or 120 #Solvent oil.
Embodiment 4, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 2: 1 be 80 ℃ of following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil or 120 #Solvent oil.
Embodiment 5, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 5: 1 be 10 ℃ of following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil or 120 #Solvent oil.
Embodiment 6, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 8: 1 be 50 ℃ of following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil or 120 #Solvent oil.
Embodiment 7, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 10: 1 be 80 ℃ of following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil or 120 #Solvent oil.
Embodiment 8, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 0.5: 1 to 10: 1 be 10 ℃ to 80 ℃ following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts aromatic hydrocarbons or condensate oil or sherwood oil.
Embodiment 9, this method for recovering sandy oil-containing sludge is undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 0.5: 1 to 10: 1 be 10 ℃ to 80 ℃ following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil, 120 #The mixture of solvent oil, aromatic hydrocarbons, condensate oil, sherwood oil.
At the foregoing description 1 to 9, can further carry out following technical measures: can with isolated dirty sand again water embathe, institute's water preferably adopts oilfield sewage, the washing water after embathing are carried out three phase separation after, the water recycling of telling.Isolated water layer or embathe separation after washing water recirculation after electric floating processing use.
In the above-described embodiments: in extraction process, when the sandy oil-containing sludge in oil field was difficult for layering, the per-cent of gross weight of pressing the sandy oil-containing sludge in extraction solvent and oil field in the sandy oil-containing sludge in extraction solvent and oil field added 0.5% to 5% inorganic salt.When containing fabric, bar, big block in the sandy oil-containing sludge in the oil field, before extraction earlier with the sandy oil-containing sludge in oil field in fabric, bar, big block screen out.In the extracting operation process, extraction plant preferably adopts dual horizontal axle extraction plant.
Through detecting, through the silt particle oil-containing of separating behind the foregoing description reach national stacking standard (<3000mg/kg).

Claims (10)

1. method for recovering sandy oil-containing sludge, it is characterized in that being undertaken by following step: with the sandy oil-containing sludge in extraction solvent and oil field be by volume 0.5: 1 to 10: 1 be 10 ℃ to 80 ℃ following thorough mixing in temperature, oil dissolves in the extraction solvent and forms three layers of separate stage, then extraction solvent layer, water layer and dirty sand are separated from each other, the extraction solvent layer after will separating again obtains oil and extraction solvent respectively by the distillation of normal pressure or decompression; Wherein, extraction solvent adopts 6 #Solvent oil, 120 #The mixture of one or more in solvent oil, aromatic hydrocarbons, condensate oil, the sherwood oil.
2. method for recovering sandy oil-containing sludge according to claim 1, it is characterized in that with isolated dirty sand again water embathe.
3. method for recovering sandy oil-containing sludge according to claim 2 is characterized in that isolated dirty sand is embathed with oilfield sewage again.
4. according to claim 2 or 3 described method for recovering sandy oil-containing sludge, after the washing water after it is characterized in that embathing carry out three phase separation, the water recycling of telling.
5. the recirculation after electric floating processing of method for recovering sandy oil-containing sludge according to claim 4, the washing water after it is characterized in that isolated water layer or embathing separation is used.
6. according to claim 1 or 2 or 3 described method for recovering sandy oil-containing sludge, it is characterized in that in the sandy oil-containing sludge in extraction solvent and oil field per-cent by the gross weight of the sandy oil-containing sludge in extraction solvent and oil field adds 0.5% to 5% inorganic salt.
7. method for recovering sandy oil-containing sludge according to claim 5 is characterized in that in the sandy oil-containing sludge in extraction solvent and oil field per-cent by the gross weight of the sandy oil-containing sludge in extraction solvent and oil field adds 0.5% to 5% inorganic salt.
8. according to claim 1 or 2 or 3 described method for recovering sandy oil-containing sludge, it is characterized in that before extraction earlier with the sandy oil-containing sludge in oil field in fabric, bar, big block screen out.
9. method for recovering sandy oil-containing sludge according to claim 7, it is characterized in that before extraction earlier with the sandy oil-containing sludge in oil field in fabric, bar, big block screen out.
10. method for recovering sandy oil-containing sludge according to claim 9 is characterized in that the extraction plant in the extracting operation process adopts dual horizontal axle extraction plant.
CN200910113612A 2009-12-29 2009-12-29 Method for recovering sandy oil-containing sludge Pending CN101734834A (en)

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Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102408176A (en) * 2010-09-25 2012-04-11 中国石油化工股份有限公司 System and method for treating oil-containing sludge
CN103058471A (en) * 2011-10-21 2013-04-24 中国石油化工股份有限公司 Method for treatment of oil sludge by thermal treatment-supercritical extraction
CN103113912A (en) * 2013-03-13 2013-05-22 天津市朗敦环保科技有限公司 Method for separating and extracting crude oil from oil sand
CN103241913A (en) * 2012-02-07 2013-08-14 中国石油天然气股份有限公司 Combined treatment method for oil-containing sludge
CN103420548A (en) * 2012-05-15 2013-12-04 中国石油天然气股份有限公司 Composite extraction solvent of oil-containing sludge
CN103570199A (en) * 2012-07-19 2014-02-12 中国石油天然气股份有限公司 Efficient extraction method for oil-containing sludge
CN103833105A (en) * 2014-02-24 2014-06-04 中国海洋石油总公司 Method for treating oil-accumulated sludge and recycling crude oil
CN104609682A (en) * 2013-11-04 2015-05-13 浙江海洋学院 Tank body oil sludge treatment method
CN104891756A (en) * 2015-06-03 2015-09-09 温州大学 Oil sludge recovery device and method based on sufficient stirring
CN106966561A (en) * 2017-04-19 2017-07-21 大连建华污泥处理有限公司 Oil-bearing sludge treatment equipment and technique
CN107129824A (en) * 2017-05-23 2017-09-05 重庆理工大学 A kind of method for reclaiming greasy filth petrochina
CN108704673A (en) * 2018-05-31 2018-10-26 上海华畅环保设备发展有限公司 Ebullated bed wood tar adds the de-oiling method and device of the outer waste discharge catalyst of hydrogen
CN108704672A (en) * 2018-05-31 2018-10-26 上海华畅环保设备发展有限公司 Ebullated bed wood tar adds the on-line regeneration method and apparatus of hydrogen decaying catalyst
CN110759614A (en) * 2019-10-29 2020-02-07 中国石油化工股份有限公司 Oil removing method for tank cleaning oil sludge before drying
CN110903008A (en) * 2019-12-16 2020-03-24 湖北中油科昊机械制造有限公司 Treatment method of oil-based mud

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102408176A (en) * 2010-09-25 2012-04-11 中国石油化工股份有限公司 System and method for treating oil-containing sludge
CN102408176B (en) * 2010-09-25 2013-07-31 中国石油化工股份有限公司 System and method for treating oil-containing sludge
CN103058471A (en) * 2011-10-21 2013-04-24 中国石油化工股份有限公司 Method for treatment of oil sludge by thermal treatment-supercritical extraction
CN103241913A (en) * 2012-02-07 2013-08-14 中国石油天然气股份有限公司 Combined treatment method for oil-containing sludge
CN103241913B (en) * 2012-02-07 2015-04-29 中国石油天然气股份有限公司 Combined treatment method for oil-containing sludge
CN103420548A (en) * 2012-05-15 2013-12-04 中国石油天然气股份有限公司 Composite extraction solvent of oil-containing sludge
CN103420548B (en) * 2012-05-15 2016-01-20 中国石油天然气股份有限公司 A kind of compound extracting solvent of oily sludge
CN103570199A (en) * 2012-07-19 2014-02-12 中国石油天然气股份有限公司 Efficient extraction method for oil-containing sludge
CN103570199B (en) * 2012-07-19 2015-02-25 中国石油天然气股份有限公司 Efficient extraction method for oil-containing sludge
CN103113912A (en) * 2013-03-13 2013-05-22 天津市朗敦环保科技有限公司 Method for separating and extracting crude oil from oil sand
CN104609682A (en) * 2013-11-04 2015-05-13 浙江海洋学院 Tank body oil sludge treatment method
CN103833105A (en) * 2014-02-24 2014-06-04 中国海洋石油总公司 Method for treating oil-accumulated sludge and recycling crude oil
CN103833105B (en) * 2014-02-24 2016-03-23 中国海洋石油总公司 A kind of method containing gathering oil-sludge treatment and crude oil recovery
CN104891756A (en) * 2015-06-03 2015-09-09 温州大学 Oil sludge recovery device and method based on sufficient stirring
CN106966561A (en) * 2017-04-19 2017-07-21 大连建华污泥处理有限公司 Oil-bearing sludge treatment equipment and technique
CN107129824A (en) * 2017-05-23 2017-09-05 重庆理工大学 A kind of method for reclaiming greasy filth petrochina
CN108704673A (en) * 2018-05-31 2018-10-26 上海华畅环保设备发展有限公司 Ebullated bed wood tar adds the de-oiling method and device of the outer waste discharge catalyst of hydrogen
CN108704672A (en) * 2018-05-31 2018-10-26 上海华畅环保设备发展有限公司 Ebullated bed wood tar adds the on-line regeneration method and apparatus of hydrogen decaying catalyst
CN110759614A (en) * 2019-10-29 2020-02-07 中国石油化工股份有限公司 Oil removing method for tank cleaning oil sludge before drying
CN110903008A (en) * 2019-12-16 2020-03-24 湖北中油科昊机械制造有限公司 Treatment method of oil-based mud

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