I. Overview
Polyanionic cellulose (Poly anioniccellulose) referred to as PAC, is from natural cellulose by chemical modification and the obtained water-soluble derivatives of cellulose ethers, is an important water-soluble cellulose ether, white or slightly yellow powder, non-toxic, tasteless, it can be dissolved in water, have good heat stability, and salt-tolerance, anti-bacterial and strong. The product slurry prepared with a good drop of fluid loss, and suppression, of a higher temperature. Widely used in oil drilling, especially in salt water wells and offshore oil drilling.

Second, PAC features
Ionic cellulose ether is a high purity, high degree of substitution, substituent distribution and so on. Can be used as thickener, rheology modifier, water, etc. down.
Suitable for use in salt water from fresh water to the saturation of any mud. 
PAC low viscosity-type filtration can effectively reduce the volume of the system without a significant increase in mucus, especially in systems with high solid content. 
Blood plasma-based PAC-made high, the role of obvious fluid loss. In particular, for low solid-phase slurry and solid-phase saline mud. PAC fluid mud can be prepared in high salt medium clay and shale inhibition dispersion and expansion of the shaft so that the pollution under control. 
Excellent drilling mud and workover fluids, fracturing fluid is also efficient.

Third, PAC Application
1, PAC application in the drilling fluid. PAC for fluid loss inhibitors and water is ideal, PAC fluid mud can be prepared in high salt medium clay and shale inhibition dispersion and expansion of the shaft so that the pollution under control.

2, PAC workover fluid in the application.
PAC prepared using workover fluid is a low-solid-phase, and not because of the solid layer and the blocking of the infiltration capacity of the production would not be harmful to the production floor; and the loss of low water, so that production level to reduce the amount of water, and access to water emulsion will be formed by blocking phenomenon Township.
PAC prepared using workover fluid to provide hydraulic workover other advantages not available.
Production level to protect against permanent damage;
Clean the hole with a carrying capacity, and the maintenance of boreholes to reduce the workload;
Resistance to water and sediment have the ability to infiltrate and few foaming; 
Can be stored or transferred between the wells and wells, and workover fluid mud than the average and low cost.

3, PAC in the fracturing fluid applications.
PAC prepared by fracturing fluid capability 2% KCI solution (the preparation of the fracturing fluid must be added) and dissolution performance, ease of use, you can Site preparation, and gel fast, strong ability to carry sand. Osmotic pressure in the formation of low use, and its fracturing effect of the more remarkable.