Oil and gas reservoir protection is an important part of testing potassium formate drilling fluid system

Drilling fluid is the first foreign fluid that contacts the reservoir. In the past, the traditional solution at home and abroad was to use asphalt and ultra-fine solid particles for physical plugging, combined with chemical suppression technology. After the liquid and solid phases invaded the reservoir, they would affect the reservoir more or less. Now, from the selective physical plugging to the non-selective chemical filming plugging, the use of potassium formate drilling fluid has also upgraded the industry technology.

With so many drilling fluids, why can the potassium formate drilling fluid system be prominently used in the protection of oil and gas reservoirs and widely used?

The mechanism of action of potassium formate drilling fluid:

(1) The filtrate of potassium formate drilling fluid has relatively high minerality, small surface tension, and good compatibility with the reservoir, which reduces the water sensitivity damage and water lock damage of low permeability reservoirs, which is beneficial to reservoir protection.

(2) The HCOO ion of potassium formate and the positive charge of the clay end face form a barrier between the positively charged site and water, prevent hydration, stabilize the clay, reduce the formation damage caused by sensitive minerals, and protect the reservoir purpose.

(3) The HCOO ion of potassium formate and water molecules can form hydrogen bonds, and have a strong "binding" ability to free water, which makes the drilling fluid filtrate viscosity higher and not easy to enter the formation.

Characteristics of potassium formate drilling fluid:

(1) Potassium formate drilling fluid has good inhibition and good compatibility with the reservoir.

(2) The components of drilling fluid are easily soluble in water and more biodegradable.

(3) It is less corrosive to drilling tools.

Applications of potassium formate drilling fluid:

From 2002 to 2007, potassium formate drilling fluids have been applied on-site in Dagang and Jidong oilfields successively, and achieved good reservoir protection effects. The recovery value of the average permeability of the popularized well reservoir reached 91.58%, and the average oil production The adjacent wells have improved to varying degrees, and the application wells in Jidong Oilfield have increased several times compared with the adjacent wells. At present, potassium formate drilling fluid has become the preferred drilling fluid system for the horizontal well reservoir section of Jidong Oilfield.

In recent years, due to the increasing number of deep wells, ultra-deep wells, and offshore drilling, the instability of the borehole wall and reservoir damage are problems that must be solved during drilling. The potassium formate drilling fluid system solves the bottleneck that traditional drilling fluids cannot solve, protects oil and gas resources, and plays an important role in improving the technology of the industry.