CN-121990700-A - Co-production method of hydrogen lithium thermoelectric oil in gas field produced water

Abstract

The invention discloses a method for coproducing hydrogen, lithium and thermooil in gas field produced water, which realizes comprehensive utilization of gas field produced water, uses photovoltaic or wind power as power, and recycles condensate in water through a sedimentation microfiltration unit, the obtained pretreated water is sent into a deep treatment unit to be treated to obtain desalted water and strong brine, the strong brine is used for extracting lithium by a brine lithium extraction device, the desalted water is used for hydrogen production by an alkaline water electrolysis device, waste heat generated in the hydrogen production process is used for evaporating and zero discharging the concentrated water after extracting lithium, thereby recycling condensate, lithium and waste heat in the produced water treatment and hydrogen production process, and finally realizing zero emission of waste water and closed loop of new energy.

Inventors

• FENG QITAO
• WANG LINA
• ZENG RUI
• YANG GUANG
• WANG GUOZHU
• LIU JIAMING
• ZHA GUANGPING
• DU YINAN
• BAI HONGSHENG
• LI HUASHAN
• LIN LIANG

Assignees

• 长庆工程设计有限公司
• 中国石油天然气集团有限公司

Dates

Publication Date

20260508

Application Date

20241104

Claims (7)

1. 1. The method for coproducing the lithium hydrogen and the thermoelectricity oil from the gas field is characterized by comprising the following steps of: Step 1, delivering gas field produced water into a sedimentation microfiltration unit for separation and filtration to obtain condensate oil and pretreated water, and delivering a condensate oil product; step 2, sending the pretreated water obtained in the step 1 into a deep treatment unit for filtering and desalting to obtain desalted water and strong brine; Step 3, sending the desalted water obtained in the step 2 into an alkaline water electrolysis device to produce hydrogen to obtain hydrogen, and sending out a hydrogen product; Step 4, sending the strong brine obtained in the step 2 into a brine lithium extraction device for extracting lithium to obtain lithium salt and strong water, and sending out a lithium salt product; step 5, waste heat generated by alkali liquor of the alkaline water electrolysis device in the step3 is sent to an MVR evaporation device to heat and evaporate and crystallize the concentrated water obtained in the step 4; in the steps 1-5, the sedimentation microfiltration unit, the advanced treatment unit, the alkaline water electrolysis device, the brine lithium extraction device and the MVR evaporation device all provide power through photovoltaic or wind power.
2. 2. The method for co-production of hydrogen lithium thermoelectricity oil from gas field produced water according to claim 1, wherein the sedimentation micro-filtration unit in the step 1 comprises a sedimentation tank and a micro-filtration filter, wherein the gas field produced water is firstly sent into the sedimentation tank for gravity sedimentation separation to obtain condensate and deoiled water, and then the deoiled water is sent into the micro-filtration filter for membrane separation to remove impurities to obtain pretreated water.
3. 3. The method for co-production of hydrogen, lithium and thermoelectricity from gas field produced water as claimed in claim 1, wherein the advanced treatment unit in step 2 comprises an ultrafiltration filter, a nanofiltration filter, a reverse osmosis filter and an electrodialyzer, wherein the pretreated water is firstly sequentially sent to the ultrafiltration filter, the nanofiltration filter and the reverse osmosis filter for membrane separation and impurity removal to obtain filtered water, and the filtered water is then sent to the electrodialyzer for continuous electric desalting to obtain desalted water and strong brine.
4. 4. The method for producing hydrogen, lithium and heat-power oil from gas field produced water according to claim 1, wherein the alkaline water electrolysis device in the step 3 is an alkaline electrolysis tank, and desalted water is sent into the alkaline electrolysis tank for electrolysis to obtain hydrogen and oxygen.
5. 5. The method for producing hydrogen, lithium and heat and power oil from gas field as claimed in claim 4, wherein the alkaline solution temperature in the alkaline electrolytic tank is controlled to be 80-90 ℃ in the step 3.
6. 6. The method for producing hydrogen-lithium-ion-fuel co-production of gas field produced water according to claim 1, wherein the brine lithium extraction device in the step 4 is a continuous ion exchange device.
7. 7. The method for producing hydrogen-lithium-ion fuel oil from gas field as defined in claim 1, wherein the brine lithium extraction device in the step 4 is a centrifugal extractor.

Description

Co-production method of hydrogen lithium thermoelectric oil in gas field produced water Technical Field The invention belongs to the technical field of gas field produced water co-production methods, and particularly relates to a gas field produced water lithium hydrogen heat and power oil co-production method. Background The annual production produced water of the Changqing gas field is about 247 square, part of produced water contains 500-150000 mg/l of condensate oil and 6-80 mg/l of lithium, 6.6 ten thousand tons of hydrogen can be produced in the expected year after treatment, but the stratum is not filled again at present, and the waste heat generated in the hydrogen production process of the electrolytic water is dissipated by a cooling tower matched with the present, so that the heat energy is not effectively utilized, the resource utilization is urgently needed, if the waste can be changed into the valuable, the resource is generated while the environmental protection problem is solved, the method has important significance for optimizing the structure of the domestic oil and gas upstream business energy, and the deep decarburization and the green low-carbon transformation of the oil and gas field development can be further realized. Disclosure of Invention The invention aims to provide a gas field produced water lithium hydrogen heat and power oil co-production method, which solves the problem that the produced water of the existing gas field is ineffective to reinject into a stratum. The technical scheme adopted by the invention is that the method for coproducing the lithium hydrogen and the thermoelectricity oil from the gas field comprises the following steps: Step 1, delivering gas field produced water into a sedimentation microfiltration unit for separation and filtration to obtain condensate oil and pretreated water, and delivering a condensate oil product; step 2, sending the pretreated water obtained in the step 1 into a deep treatment unit for filtering and desalting to obtain desalted water and strong brine; step 3, sending the desalted water obtained in the step 2 into an alkaline water electrolysis device to perform alkaline water electrolysis to prepare hydrogen AWE to obtain hydrogen, and sending out a hydrogen product; Step 4, sending the strong brine obtained in the step 2 into a brine lithium extraction device for extracting lithium to obtain lithium salt and strong water, and sending out a lithium salt product; step 5, waste heat generated by alkali liquor of the alkaline water electrolysis device in the step3 is sent to an MVR evaporation device to heat and evaporate and crystallize the concentrated water obtained in the step 4; in the steps 1-5, the sedimentation microfiltration unit, the advanced treatment unit, the alkaline water electrolysis device, the brine lithium extraction device and the MVR evaporation device all provide power through photovoltaic or wind power. The present invention is also characterized in that, The sedimentation microfiltration unit in the step 1 comprises a sedimentation tank and a microfiltration MF filter, wherein gas field produced water is firstly sent into the sedimentation tank for gravity sedimentation separation to obtain condensate oil and deoiling water, and then the deoiling water is sent into the microfiltration filter for membrane separation to remove impurities to obtain pretreated water. The advanced treatment unit in the step 2 comprises an ultrafiltration UF filter, a nanofiltration NF filter, a reverse osmosis RO filter and an electrodialysis device EDI, wherein pretreated water is firstly sequentially sent into the ultrafiltration filter, the nanofiltration filter and the reverse osmosis filter to carry out membrane separation and impurity filtering to obtain filtered water, and then the filtered water is sent into the electrodialysis device to carry out continuous electric desalting to obtain desalted water and strong brine. The alkaline water electrolysis device in the step 3 is an alkaline electrolysis tank, the temperature of alkaline liquor in the alkaline electrolysis tank is controlled to be 80-90 ℃, and desalted water is sent into the alkaline electrolysis tank for electrolysis to obtain hydrogen and oxygen. The brine lithium extraction device in the step 4 is continuous ion exchange equipment or a centrifugal extractor. The invention has the beneficial effects that the hydrogen-lithium-heat-power oil co-production method for the produced water of the gas field realizes the comprehensive utilization of the produced water of the gas field, takes green electricity as power, and realizes the zero discharge of wastewater and closed loop of new energy by recycling condensate oil, lithium and waste heat in the produced water in the process of advanced treatment of the produced water, wherein concentrated brine in the process of advanced treatment is used for extracting lithium, desalted water after advanced treatment is used fo