CN115180746A - Treatment method of high-hardness fracturing flow-back fluid - Google Patents
Treatment method of high-hardness fracturing flow-back fluid Download PDFInfo
- Publication number
- CN115180746A CN115180746A CN202210960539.6A CN202210960539A CN115180746A CN 115180746 A CN115180746 A CN 115180746A CN 202210960539 A CN202210960539 A CN 202210960539A CN 115180746 A CN115180746 A CN 115180746A
- Authority
- CN
- China
- Prior art keywords
- back fluid
- fracturing flow
- hardness
- fracturing
- fluid
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 239000012530 fluid Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 27
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 30
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 26
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 26
- 238000005273 aeration Methods 0.000 claims abstract description 19
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000011575 calcium Substances 0.000 claims abstract description 14
- 239000002518 antifoaming agent Substances 0.000 claims abstract description 13
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 13
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 13
- 239000007789 gas Substances 0.000 claims abstract description 7
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 6
- 239000011777 magnesium Substances 0.000 claims abstract description 6
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 6
- 229910001424 calcium ion Inorganic materials 0.000 abstract description 10
- JLVVSXFLKOJNIY-UHFFFAOYSA-N Magnesium ion Chemical compound [Mg+2] JLVVSXFLKOJNIY-UHFFFAOYSA-N 0.000 abstract description 9
- 229910001425 magnesium ion Inorganic materials 0.000 abstract description 9
- 239000010865 sewage Substances 0.000 abstract description 7
- 239000002244 precipitate Substances 0.000 abstract description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000002351 wastewater Substances 0.000 description 6
- 230000008569 process Effects 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 239000006260 foam Substances 0.000 description 3
- 238000005342 ion exchange Methods 0.000 description 3
- 238000001223 reverse osmosis Methods 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 2
- 238000003556 assay Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229920002521 macromolecule Polymers 0.000 description 2
- 239000012492 regenerant Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000005189 flocculation Methods 0.000 description 1
- 230000016615 flocculation Effects 0.000 description 1
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 description 1
- 239000000347 magnesium hydroxide Substances 0.000 description 1
- 229910001862 magnesium hydroxide Inorganic materials 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000008234 soft water Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/722—Oxidation by peroxides
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F2001/007—Processes including a sedimentation step
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/10—Nature of the water, waste water, sewage or sludge to be treated from quarries or from mining activities
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The invention relates to a method for treating high-hardness fracturing flowback fluid. The invention comprises the following steps: 1) Testing the fracturing flow-back fluid, measuring the calcium and magnesium content of the fracturing flow-back fluid to obtain the hardness of the fracturing flow-back fluid, and giving the adding amount of sodium hydroxide; 2) Putting the fracturing flow-back fluid into an aeration tank, adding sodium hydroxide, and adjusting the pH value to 12; 3) And opening the aeration tank to introduce carbon dioxide gas into the aeration tank, simultaneously adding hydrogen peroxide and a defoaming agent, and ending the aeration when the PH of the fracturing flow-back fluid is 7. The method has the advantages of reducing the content of calcium and magnesium ions in the sewage and reducing the generation of calcium and magnesium ion precipitates after reinjection.
Description
Technical Field
The invention relates to the field of environmental protection, in particular to a method for treating high-hardness fracturing flowback fluid.
Background
The oilfield reinjection of sewage and high-hardness sewage generate a large amount of calcium and magnesium ions to scale and block the stratum, and the reinjection of high-hardness fracturing flowback fluid influences the compatibility.
At present, the softening method of high-concentration salt-containing wastewater mainly comprises a chemical method and an ion exchange method, and the main mechanism of the softening method is to add some chemical agents into various compounds such as calcium, magnesium, calcium, magnesium and the like in the high-concentration salt-containing wastewater to enable calcium and magnesium ions to form insoluble salt to be removed through precipitation or flocculation. The high-salinity wastewater has high hardness and large water amount, and the chemical quantity required by the chemical treatment is relatively large, so the cost is high. Meanwhile, a chemical method often generates a large amount of sludge, so that secondary pollution to the environment is caused. The ion exchange method is widely applied to the hardness-removing wastewater for producing soft water. The ion exchange method can effectively remove calcium and magnesium ions, but the regeneration problem of the resin and the carrier can occur during the use process. The regenerant generally needs the regenerant, has high cost and secondary pollution to the environment, and is not suitable for the requirement of softening high-hardness wastewater
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides a method for treating high-hardness fracturing flow-back fluid, which has the advantages of reducing the content of calcium and magnesium ions in sewage and reducing the generation of calcium and magnesium ion precipitates after reinjection.
The technical solution of the invention is as follows: the invention relates to a method for treating high-hardness fracturing flowback fluid, which is characterized by comprising the following steps of: the method comprises the following steps:
1) Testing the fracturing flow-back fluid, measuring the calcium and magnesium content of the fracturing flow-back fluid to obtain the hardness of the fracturing flow-back fluid, and giving the adding amount of sodium hydroxide;
2) Putting the fracturing flow-back fluid into an aeration tank, adding sodium hydroxide, and adjusting the pH value to 12;
3) And opening the aeration tank to introduce carbon dioxide gas into the aeration tank, simultaneously adding hydrogen peroxide and a defoaming agent, and ending when the pH of the fracturing flow-back fluid is 7. Adding hydrogen peroxide to oxidize and decompose organic molecules and macromolecular substances in the fracturing flow-back fluid, so that the viscosity of the sewage is reduced, and suspended substances in the sewage are reduced; and the defoaming agent is added to reduce the generation of foam in the aeration process and prevent foam pollution.
Further, the dosage of the hydrogen peroxide and the defoaming agent in the step 1) is as follows: the content of the added hydrogen peroxide is 1mg/L, and the content of the defoaming agent is 0.005mg/L.
Further, after the step 3), natural sedimentation is performed after the step 4) is finished.
The method for treating the high-hardness fracturing flow-back fluid comprises the steps of firstly pretreating the fracturing flow-back fluid to adjust the pH of the fracturing flow-back fluid to 12, forming calcium carbonate precipitates by using carbon dioxide under alkaline conditions in calcium ions, effectively reducing the content of the calcium ions in water, forming magnesium hydroxide precipitates when the pH value exceeds 10, effectively reducing the content of the magnesium ions in the water, then introducing carbon dioxide gas for aeration, and ending when the pH value of the fracturing flow-back fluid is 7 by aeration. Consuming OH of the wastewater during the carbon dioxide introduction - The pH of the water is lowered, and when the pH is lower than 7, the water is added with HCO after carbon dioxide is introduced 3 2- When the reaction temperature is reduced to 7, which is the reaction end point, hydrogen peroxide is added to oxidize organic matters and macromolecular substances in water in the carbon dioxide aeration process, and a defoaming agent is added to prevent a large amount of foam generated in the aeration process from polluting the surrounding environment. The invention can effectively reduce the hardness of the fracturing flow-back fluid, reduce the operating pressure of reverse osmosis in the traditional reverse osmosis treatment process, improve the reverse osmosis water yield, reduce the scale formation of calcium and magnesium ions after reinjection and improve the compatibility of sewage.
Detailed Description
The invention provides a method for treating high-hardness fracturing flow-back fluid, which comprises the following steps:
1) Testing the fracturing flow-back fluid, measuring the calcium and magnesium content of the fracturing flow-back fluid to obtain the hardness of the fracturing flow-back fluid, and giving the adding amount of sodium hydroxide; (ii) a
2) Putting the fracturing flow-back fluid into an aeration tank, adding sodium hydroxide, and adjusting the pH value to 12;
3) Opening the aeration tank to introduce carbon dioxide gas into the aeration tank, simultaneously adding hydrogen peroxide and a defoaming agent, and ending the aeration when the PH of the fracturing flow-back fluid is 7; the content of the added hydrogen peroxide is 1mg/L, and the content of the defoaming agent is 0.005mg/L;
4) And naturally settling after finishing.
The specific application examples and experimental data of the present invention are as follows:
the first embodiment is as follows:
assay 1000m 3 Hardness of fracturing flowback fluidAnd (3) adding 7 tons of sodium hydroxide at 12000mg/L, adjusting the pH value to 12, adding 1 ton of hydrogen peroxide and 50 kg of defoaming agent, introducing carbon dioxide gas, finishing the pH reduction of the fracturing flow-back fluid to 7, consuming 5 tons of liquid carbon dioxide, naturally settling after the completion of the settlement, and measuring the hardness of the fracturing flow-back fluid to be 5000mg/L and the suspended matter to be 10mg/L after the completion of the settlement.
Example two
Assay 1000m 3 The hardness of the fracturing flow-back fluid is 20000mg/L, 12 tons of sodium hydroxide are added, the PH value is adjusted to 12, 1 ton of hydrogen peroxide and 50 kilograms of defoaming agent are added, carbon dioxide gas is introduced, the PH value of the fracturing flow-back fluid is reduced to 7, 5 tons of liquid carbon dioxide is consumed, the fracturing flow-back fluid naturally settles after the completion of the settlement, the measured hardness of the fracturing flow-back fluid is 8000mg/L, and the suspended matter is 13mg/L.
The experimental data show that the method can effectively reduce the hardness of the fracturing flow-back fluid and meet the reinjection requirement of the fracturing flow-back fluid.
It should be noted that the above-mentioned embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.
The present invention and the technical contents not specifically described in the above embodiments are the same as the prior art.
The present invention is not limited to the above-described embodiments, and the present invention can be implemented with the above-described advantageous effects.
Claims (3)
1. A method for treating high-hardness fracturing flowback fluid is characterized by comprising the following steps: the method comprises the following steps:
1) Testing the fracturing flow-back fluid, measuring the calcium and magnesium content of the fracturing flow-back fluid to obtain the hardness of the fracturing flow-back fluid, and giving the adding amount of sodium hydroxide;
2) Putting the fracturing flow-back fluid into an aeration tank, adding sodium hydroxide, and adjusting the pH value to 12;
3) And opening the aeration tank to introduce carbon dioxide gas into the aeration tank, simultaneously adding hydrogen peroxide and a defoaming agent, and ending when the pH of the fracturing flow-back fluid is 7.
2. The method of treating high hardness frac flowback fluid of claim 1, wherein: the adding amount of the hydrogen peroxide and the defoaming agent in the step 1) is as follows: the content of the added hydrogen peroxide is 1mg/L, and the content of the defoaming agent is 0.005mg/L.
3. The method for treating a high-hardness fracturing flow-back fluid according to claim 1 or 2, wherein: and 3) after the step 4), naturally settling.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210960539.6A CN115180746A (en) | 2022-08-18 | 2022-08-18 | Treatment method of high-hardness fracturing flow-back fluid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210960539.6A CN115180746A (en) | 2022-08-18 | 2022-08-18 | Treatment method of high-hardness fracturing flow-back fluid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115180746A true CN115180746A (en) | 2022-10-14 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210960539.6A Pending CN115180746A (en) | 2022-08-18 | 2022-08-18 | Treatment method of high-hardness fracturing flow-back fluid |
Country Status (1)
| Country | Link |
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| CN (1) | CN115180746A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117682731A (en) * | 2024-02-02 | 2024-03-12 | 广州市迈源科技有限公司 | Full quantification treatment process and treatment system for calcium sulfate type high-hardness fracturing flowback fluid |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2017096569A1 (en) * | 2015-12-07 | 2017-06-15 | 江苏久吾高科技股份有限公司 | Method and apparatus for treating fracturing flowback of oil-gas field by using ceramic membrane |
| CN109574394A (en) * | 2018-12-21 | 2019-04-05 | 陕西延长油田压裂材料有限公司 | A kind of fracturing outlet liquid processing method |
| CN110482738A (en) * | 2019-08-08 | 2019-11-22 | 麦王环境技术股份有限公司 | A kind of Integral waste water hardness removing device and processing method |
| CN111072213A (en) * | 2019-12-31 | 2020-04-28 | 上海同济建设科技股份有限公司 | Zero-discharge treatment process and device for fractured rock wastewater |
| CN211056858U (en) * | 2019-11-04 | 2020-07-21 | 内蒙古恒盛环保科技工程有限公司 | Foam processing unit in flowing back processing procedure is returned in oil gas field fracturing |
| CN112794501A (en) * | 2020-12-29 | 2021-05-14 | 西北大学 | Method for removing boron ions in fracturing flow-back fluid |
| CN114031205A (en) * | 2021-08-31 | 2022-02-11 | 鄂尔多斯市昊鑫瑞源科净工程有限公司 | High-hardness wastewater treatment method for fracturing flow-back fluid of oil and gas field |
-
2022
- 2022-08-18 CN CN202210960539.6A patent/CN115180746A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2017096569A1 (en) * | 2015-12-07 | 2017-06-15 | 江苏久吾高科技股份有限公司 | Method and apparatus for treating fracturing flowback of oil-gas field by using ceramic membrane |
| CN109574394A (en) * | 2018-12-21 | 2019-04-05 | 陕西延长油田压裂材料有限公司 | A kind of fracturing outlet liquid processing method |
| CN110482738A (en) * | 2019-08-08 | 2019-11-22 | 麦王环境技术股份有限公司 | A kind of Integral waste water hardness removing device and processing method |
| CN211056858U (en) * | 2019-11-04 | 2020-07-21 | 内蒙古恒盛环保科技工程有限公司 | Foam processing unit in flowing back processing procedure is returned in oil gas field fracturing |
| CN111072213A (en) * | 2019-12-31 | 2020-04-28 | 上海同济建设科技股份有限公司 | Zero-discharge treatment process and device for fractured rock wastewater |
| CN112794501A (en) * | 2020-12-29 | 2021-05-14 | 西北大学 | Method for removing boron ions in fracturing flow-back fluid |
| CN114031205A (en) * | 2021-08-31 | 2022-02-11 | 鄂尔多斯市昊鑫瑞源科净工程有限公司 | High-hardness wastewater treatment method for fracturing flow-back fluid of oil and gas field |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117682731A (en) * | 2024-02-02 | 2024-03-12 | 广州市迈源科技有限公司 | Full quantification treatment process and treatment system for calcium sulfate type high-hardness fracturing flowback fluid |
| CN117682731B (en) * | 2024-02-02 | 2024-04-16 | 广州市迈源科技有限公司 | Full quantification treatment process and treatment system for calcium sulfate type high-hardness fracturing flowback fluid |
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