Jianghan Oilfield is tightly controlling the "niubizi" of declining control

"Polymer flooding has officially entered the field test for one month, and the progress is normal.
The injection pressure and injection viscosity of the polymer injection well meet the design requirements of the scheme
.

" May 19, the relevant person in charge of Jianghan Oilfield Exploration and Development Research Institute Say

After decades of development, Jianghan Oilfield has problems such as difficulty in well pattern adjustment in old areas, difficulty in improving water quality along the way, and difficulty in upgrading development technology
.

The most important thing in the development of stock resources is to control decline .

Grasp the plan design and make the actual control decrease

Controlling the decline rate is a systematic project involving multiple professional fields such as oil reservoirs, wellbore, and surface
.

The Jianghan Oilfield has complex reservoir types, large differences in production stages, and scattered block distribution.

"The current injection-production ratio of the fourth member of Shahejie Formation is 81%, the cumulative injection-production ratio is 1.
42, and there are 11 under-injection and non-injection wells, affecting the daily water injection volume of 269 cubic meters, which are concentrated in the Sha 4 1 and Sha 4 6 sand formations.
.
.
" In the room, scientific researchers are enthusiastically discussing the adjustment of injection and production in the 14 districts, and strive to implement the water injection investigation work in detail
.

　　The investigation found that there are 913 wells in Jianghan Oilfield affected by imperfect injection and production, contradictions in longitudinal strata, and inefficient and ineffective water injection, with a daily oil output of 805 tons, accounting for 25.
5%; and 646 wells affected by edge water and injection water advancement.
, With a daily output of 724 tons of oil, accounting for 22.
9% of the total
.

The tapping of the potential of these wells is critical to controlling decline

　　To find out the problems and potentials, the research institute and engineering institute will implement symptomatic measures, and formulate the oilfield control decline plan in a down-to-earth manner
.

In Jianghan Oilfield planning, during the "14th Five-Year Plan" period, the decline rate will be controlled within 8% by 2025 through fine injection and production adjustments, shut down wells and casing damage management, maintenance operations and water quality management

　　The target for this year is 9.
99%
.

At present, the oilfield is implementing flow field adjustments, pilot tests, and changing development methods to increase the "three rates" of water injection.

　　Grasp water quality monitoring, support and control decline

　　Oilfield water injection development is like cooking.
If the water quality is not up to standard, the food will be unhealthy, and stones will easily grow, which will seriously affect the intestines and other organs
.

In order to clarify the direction of water quality improvement, the Oilfield Research Institute took samples at 54 water injection nodes at 17 water injection stations in 4 oil production plants, and carried out testing and analysis of 7 control indicators and 4 auxiliary indicators

　　The analysis found that the comprehensive compliance rate of the outbound water quality was 85.
7%, but the injected water passed the station to the water distribution room and then to the wellhead.
The water quality gradually deteriorated along the way.
The pipeline was corroded and scaled, and a large amount of filthy oil was deposited, and the cleaning was not timely, causing bacteria to grow , Corrosion has intensified, water quality has deteriorated, and the water quality compliance rate at the wellhead has dropped by an average of 20%
.

　　Jianghan Oilfield improves water quality in accordance with the principles of demonstration creation, promotion and implementation, and overall improvement
.

They selected the 14 districts of the Bamian River to create a fine water injection demonstration area by optimizing the water injection pipeline network, optimizing the dosage of chemicals, and optimizing water injection management.

　　Grab polymer flooding test helps control decline

　　The Bamianhe Oilfield water drive general heavy oil reservoir has produced more than 71 million tons of geological reserves.
The current water cut is 93.
8%, and the recovery rate is only 19.
4%.
As a whole, it has entered the ultra-high water cut development stage
.
Water flooding has little room for enhanced oil recovery, why not explore polymer flooding?

　　After 5 years of indoor research, plan preparation, equipment modification and commissioning, and successful single-well test injection, the Bamianhe Oilfield high-calcium-magnesium reservoir polymer flooding field test reached the design operating conditions on April 8 this year
.

　　As of May 19, the pressure of the water injection well rose from 6.
2 MPa to 7.
4 MPa, and the polymer viscosity remained at 50-100 mPa·s, and the test progressed normally
.

　　In the next step, the Oilfield Research Institute will work closely with the Group's Exploration and Development Research Institute and Qinghe Oil Production Plant to closely follow the test process, obtain all data in a timely manner, and continuously optimize injection parameters to ensure that the test sees the expected results and help the old area control decline
.

　　(Shi Jianfen and Wu Hua)