Polyanionic cellulose (PAC for short) is a water-soluble cellulose ether with a wide range of uses. At present, it is widely used in the oil drilling industry to reduce the fluid loss of drilling fluid as much as possible.
(1) The non-dispersed drilling fluid configured with polyanionic cellulose (PAC) has a strong ability to carry drill cuttings, which can effectively inhibit the dispersion of clay and reduce the rate of clay slurry making, which is conducive to the stability of the borehole wall and effectively increases the drilling rate.
(2) The dispersion system drilling fluid configured with polyanionic cellulose has good suspending capacity, can hold more solid phases, can greatly improve particle stability, is most suitable for configuring high-density drilling fluids, and can efficiently regulate drilling fluid rheology; it can form dense and high-quality mud cakes in drilling fluid, has excellent fluid loss reduction effect, and reduces free water.
(3) The calcium-treated drilling fluid configured by polyanionic cellulose (PAC) has good calcium resistance and can prevent excessive flocculation of clay particles in the system caused by calcium ions, so that the drilling fluid can maintain a good flocculation state and keep the drilling fluid stable. The solid content and rheological properties ensure that the drilling fluid has good and stable performance.
(4) The brine drilling fluid, sea water drilling fluid, and saturated brine drilling fluid configured by PAC have low salt sensitivity, strong salt tolerance and calcium and magnesium resistance. They can be used as rheology modifiers and can achieve quickly adjust of the rheology of the drilling fluid under low dosage conditions, and at the same time, it can quickly carry out the drill cuttings and maintain a low solid content, which is beneficial to increase the drilling speed. Used as a filtrate reducer, it can form a dense mud cake. Since the filtrate filtered through the filter cake is close to the connate water of the formation, the filtrate does less damage to the oil and gas reservoir.
(5) Potassium-based drilling fluid with petroleum-grade (PAC) configuration has low sensitivity to potassium salt, calcium salt, and magnesium salt. It can quickly and efficiently adjust the rheology of this type of drilling fluid. It has a good fluid loss reduction effect and also It has excellent ability to clean drill cuttings and drill bits, and the effect is obvious when used in formations that are easy to stick.
The environmentally friendly drilling fluid configured with polyanionic cellulose is environmentally friendly, non-toxic, harmless, odorless, biodegradable, not easy to decay during use, and the maintenance cost of the drilling fluid is low. The health and safety of the construction personnel are guaranteed. It is suitable for drilling needs of various complex geological conditions, harmless to agricultural production.