CN-121974454-A - Oilfield produced water coagulation sedimentation device and method

CN121974454ACN 121974454 ACN121974454 ACN 121974454ACN-121974454-A

Abstract

The invention belongs to the technical field of oilfield water treatment, and particularly relates to an oilfield produced water coagulation sedimentation device and method. The coagulation sedimentation device comprises a sedimentation tank, the top of the sedimentation tank is provided with a filter tank and a dosing device, both the filter tank and the dosing device are communicated with the sedimentation tank, the top of the filter tank is provided with a cutting pump, and the outlet of the cutting pump is communicated with the filter tank. According to the invention, the cutting operation can be carried out on the oilfield produced water through the cutting pump, the blocking of subsequent equipment caused by overlarge impurities is avoided, the water flow can be preliminarily filtered through the first filter plate, and the filtering effect of the oilfield produced water is improved. The dosing device can control the capacity of the regulating box, and the using amount of the flocculant is controlled according to the water flow capacity in the settling box. The height of the oilfield produced water drain pipe can be adjusted through the arrangement of the lifting cylinder, a guarantee is provided for the sedimentation filtering effect of oilfield produced water, and sediment impurities of oilfield produced water can be discharged out of the sedimentation tank through the dirt collecting tank and the auger mechanism, so that the device is convenient to clean and saves labor.

Inventors

MAO HENGBO
Fu Bodan
LI YUAN
JIAN ZHAOQI
BIAN QINGHAO
RAN WANG
Luo Shuoshuo
BAI YANFENG
WU YING
WANG CHEN
OUYANG SHIKUN
ZHENG JIANGANG
ZHOU ZHIGUO
LI YAZHOU
LIU BAOLU
WEI HAIQIANG
XIAO XIONG
YANG QIANFENG

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260505
Application Date: 20241031

Claims (10)

1. The oilfield produced water coagulation sedimentation device is characterized by comprising a sedimentation tank, wherein the top of the sedimentation tank is provided with a filter tank and a dosing device, the filter tank and the dosing device are both communicated with the sedimentation tank, the top of the filter tank is provided with a cutting pump, the outlet of the cutting pump is communicated with the filter tank, and the sedimentation tank is internally provided with a stirring mechanism; the filter box is internally provided with a first filter plate and an L-shaped partition plate, the L-shaped partition plate is fixedly arranged at the bottom of the filter box, one end of the first filter plate is obliquely arranged and connected with the inner wall of the filter box, the other end of the first filter plate is connected with the L-shaped partition plate, a discharging frame is communicated with the outside of the filter box, and the L-shaped partition plate is communicated with the discharging frame; The sedimentation tank is internally provided with an inclined plane, a drain pipe, an auger mechanism and a backwater groove, the drain pipe is communicated with a water delivery pump, the backwater groove is connected with the higher side of the inclined plane, the auger mechanism is parallel to the inclined plane and extends to the outside of the sedimentation tank across the backwater groove, a sewage collecting tank is arranged on the inclined plane, the auger mechanism is arranged in the sewage collecting tank and is mutually matched with the sewage collecting tank, a second filter plate is arranged in the backwater groove, a discharge opening is arranged on the sedimentation tank, the lower end of the discharge opening is connected with the second filter plate, a collecting frame is arranged outside the sedimentation tank, the collecting tank is arranged below the inclined discharge opening, and a backwater pipe is arranged on the side wall of the sedimentation tank and is communicated with the backwater groove.
2. The oilfield produced water coagulation sedimentation device of claim 1, wherein one side of the L-shaped partition plate, which is close to the discharge frame, is an inclined surface, the discharge frame is obliquely arranged, a plugging plate is arranged at an outlet of the discharge frame, the plugging plate is arranged in a T shape, one side of the plugging plate extends into the discharge frame, a rubber sealing frame is fixedly arranged on the outer wall of the plugging plate, and a frame type sealing groove matched with the rubber sealing frame is formed in the discharge frame.
3. The oilfield produced water coagulation sedimentation device of claim 1, wherein the sedimentation tank top wall is provided with a lifting cylinder, the drain pipe is a telescopic pipe, the movable end of the lifting cylinder is connected with the water inlet end of the drain pipe through a connecting plate, and the water inlet end of the drain pipe is provided with a filter sleeve.
4. The oilfield produced water coagulation sedimentation device according to claim 1, wherein the dosing device comprises an adjusting box, a discharging pipe, an adjusting plate, an adjusting screw barrel, an adjusting screw rod, an adjusting motor and a conveying pipe, wherein scales are arranged on the adjusting box, the conveying pipe is arranged at the top of the adjusting box, the discharging pipe is arranged at the bottom of the adjusting box and is communicated with the sedimentation box, an electromagnetic valve is arranged on the discharging pipe, the adjusting plate is slidably arranged in the adjusting box, the adjusting screw barrel is fixedly arranged on the outer wall of one side of the adjusting plate, the adjusting screw barrel is slidably connected with the adjusting box, and one end of the adjusting screw rod is fixedly connected with the adjusting motor; Two first sliding grooves are formed in the inner wall of the adjusting box, a sliding plate is arranged in the adjusting box and fixedly connected with the outer wall of the adjusting screw cylinder, first sliding blocks are fixedly mounted on the outer walls of the two sides of the sliding plate, and first sliding blocks are in sliding connection with the first sliding grooves.
5. The oilfield produced water coagulation sedimentation device of claim 1, wherein the stirring mechanism comprises a stirring motor and a stirring rod, the stirring rod is horizontally arranged, a supporting plate is fixedly arranged on the inner wall of the sedimentation tank, and one end of the stirring rod is rotatably connected with the supporting plate.
6. The coagulation sedimentation device of oilfield produced water, as set forth in claim 1, wherein the feed opening of the filter box is in a shape of a frame-shaped through groove and is arranged right below the first filter plate, and the length of the feed opening is equal to the projection length of the first filter plate.
7. The oilfield produced water coagulation sedimentation device of claim 1, wherein the blanking opening of the filter box is a round hole, the bottom of the filter box is a funnel-shaped structure with a large top and a small bottom, and the filter plate is provided with a cleaning device.
8. The oilfield produced water coagulation sedimentation device as set forth in claim 7, wherein the cleaning device comprises a spiral plate and a power impeller, the spiral plate is arranged on the inner wall of the feed opening, the top of the spiral plate is an arc-shaped inclined surface, a transmission rod is arranged on the first filter plate, a rotating rod is rotatably arranged on the spiral plate, the transmission rod is meshed with the rotating rod through a gear, the power impeller is arranged at the lower end of the rotating rod, a cleaning plate is fixedly arranged at the top end of the rotating rod, a hairbrush is arranged on one side of the cleaning plate, and the hairbrush is in contact with the surface of the first filter plate.
9. An oilfield produced water coagulation sedimentation method adopting the oilfield produced water coagulation sedimentation method as defined in claim 3, which is characterized by comprising the following steps: step 1), oilfield produced water enters a cutting pump through a water inlet pipe, the cutting pump cuts impurities in the water, and then the oilfield produced water is discharged into a first filter plate of a filter box through a first water conveying pipe for primary filtration; The filtered impurities fall into the L-shaped partition plate along the first filter plate under the action of gravity and are discharged through the discharge frame; the water after the primary filtration in the step 2) enters a sedimentation tank through a feed opening to be sedimentated; step 3) opening a dosing device to add a flocculating agent, starting a stirring mechanism to enable the flocculating agent to be fully mixed with impurities in water for flocculating settling, starting a water conveying pump after a certain time, and conveying the upper water to the next working procedure through a water discharging pipe; In the flocculation sedimentation process, flocculate is settled into a sewage collecting tank under the action of gravity, an auger mechanism is started to enable the flocculate to fall into a water return tank, and the flocculate is concentrated into a discharge port and discharged into a collecting frame after being filtered by a filter plate II.
10. The method of coagulating sedimentation for oilfield produced water according to claim 9, wherein the lifting cylinder is started according to the water quality requirement of the drainage pipe in the process of conveying water flow by the water conveying pump, and the drainage pipe is driven to move up and down, so that the height of the lower end of the drainage pipe in the sedimentation tank is adjusted.

Description

Oilfield produced water coagulation sedimentation device and method Technical Field The invention belongs to the technical field of oilfield water treatment, and particularly relates to an oilfield produced water coagulation sedimentation device and method. Background With the rapid development of society, people are increasingly exploiting the earth resources, wherein petroleum resources are an important resource, basic guarantee is provided for the industrial development of human beings, in the process of exploiting resources, some underground water is exploited along with the resources, and then oilfield produced water products are formed, the oilfield produced water is waste water which can be discharged after being treated, pollution is caused to the surrounding ecological environment, and the oilfield produced water is firstly subjected to filtering and precipitation treatment on particulate matters in the oilfield produced water. In the current process of coagulation sedimentation of oilfield produced water, self-treatment equipment is generally lacking, most of oilfield produced water is discharged into a reservoir, then additives are added, particles in water flow are sedimented, and the water flow is conveyed after sedimentation is completed. Patent CN2019207680235 relates to a compact oil development fracturing flow-back fluid reinjection continuous treatment device, which comprises a tank body, the left side fixedly connected with pipeline of the tank body, the pipeline is kept away from the left end fixedly connected with pipeline blender of the tank body, the left side fixedly connected with solenoid valve of pipeline blender, the left side fixedly connected with pipeline of solenoid valve, the pipeline is kept away from the left end fixedly connected with elevator pump of solenoid valve, the right side fixedly connected with pipeline of the tank body, the pipeline is kept away from the right side fixedly connected with centrifugal pump of the tank body. The continuous treatment device for the fracturing flowback fluid is combined with the characteristics of high viscosity, serious emulsification and high pollution of the fracturing flowback fluid containing guanidine gum organic matters which are difficult to degrade, and the water quality is stable to reach the water quality standard of the water injection of the low-permeability oil reservoir after adopting the composite technology of viscosity reduction, coagulation, sedimentation separation, solid-liquid dehydration and filtration for fine treatment. But this kind of mode is in the use, and the particulate matter sediment in the oil field produced water is in the pond bottom, takes place to pile up after long time, needs personnel to descend the pond bottom to use cleaning equipment to clear up when the clearance, and complex operation is with high costs, and cleaning efficiency is low. Disclosure of Invention The invention aims to provide an oilfield produced water coagulation sedimentation device which solves the technical problems in the prior art. The invention aims to provide the coagulation sedimentation method for the oilfield produced water, which is convenient to clean, saves labor and provides guarantee for the cleaning efficiency of a sedimentation tank. Therefore, the technical scheme provided by the invention is as follows: The coagulation sedimentation device for the oilfield produced water comprises a sedimentation tank, wherein a filter tank and a dosing device are arranged at the top of the sedimentation tank, the filter tank and the dosing device are both communicated with the sedimentation tank, a cutting pump is arranged at the top of the filter tank, an outlet of the cutting pump is communicated with the filter tank, and a stirring mechanism is arranged in the sedimentation tank; the filter box is internally provided with a first filter plate and an L-shaped partition plate, the L-shaped partition plate is fixedly arranged at the bottom of the filter box, one end of the first filter plate is obliquely arranged and connected with the inner wall of the filter box, the other end of the first filter plate is connected with the L-shaped partition plate, a discharging frame is communicated with the outside of the filter box, and the L-shaped partition plate is communicated with the discharging frame; The sedimentation tank is internally provided with an inclined plane, a drain pipe, an auger mechanism and a backwater groove, the drain pipe is communicated with a water delivery pump, the backwater groove is connected with the higher side of the inclined plane, the auger mechanism is parallel to the inclined plane and extends to the outside of the sedimentation tank across the backwater groove, a sewage collecting tank is arranged on the inclined plane, the auger mechanism is arranged in the sewage collecting tank and is mutually matched with the sewage collecting tank, a second filter plate is arranged in the backwater groov