Drilling PAC

Applications of PAC in Oil Drilling Fluids (Completion Fluids)

① Cement slurries prepared with PAC can improve the fluidity of cementing fluids, giving them suitable initial viscosity and low filtration loss, while protecting the wellbore and preventing fluid from entering pores and fractures.
② Packing fluids prepared with PAC adjust the fluid's fluidity, thixotropy, and ability to suspend solids. Due to the product's good salt resistance (especially monovalent metal ions), it is particularly effective as a clean brine-type packing fluid.
③ Workover fluids prepared with polyanionic cellulose powder are low in solids, preventing blockage of the production zone's permeability and damage to the production zone. They also have low fluid loss, reducing the amount of water entering the production zone, which would otherwise cause water stagnation due to emulsion blockage.
④ Workover fluids prepared with PAC powder offer advantages not found in other workover fluids. It protects the production layer from permanent damage; it has the ability to clean the wellbore and reduces the workload of wellbore maintenance; it is resistant to water and sediment infiltration and produces very little foaming; it can be stored or transferred between wells and is less expensive than general mud workover fluids.
 

Applications of Chemically Polyanionic Cellulose in Fracturing Fluids

① Fracturing fluids prepared with Drilling Chemical Raw Materials PAC can rapidly increase viscosity, efficiently carrying proppant into well fractures, establishing permeability channels, quickly reducing filtrate loss, and rapidly increasing formation pressure, achieving efficient pressure transmission. The product leaves no residue, does not damage the formation, has high pumpability, low friction, and a certain proppant carrying capacity.
② Fracturing fluids prepared with High-purity PAC are resistant to 2% KCI solution (must be added during fracturing fluid preparation) and have good solubility. Small addition amounts are required, leaving no residue. This effectively reduces filtrate loss and exhibits good salt and temperature resistance. It is easy to use, can be prepared on-site, and has a fast gelation rate and strong proppant carrying capacity. Its fracturing effect is even more outstanding when used in low-permeability formations.
 

Product Features

· No shearing required; readily disperses into nano-sized particles upon addition to fresh and saltwater-based drilling fluids;
· Significantly reduces high-temperature, high-pressure water loss: water loss decreases with increasing pressure;
· Forms ultra-low permeability mud cake, effectively reducing the risk of differential pressure stuck pipe;
 

In practical applications, the rheological properties of drilling fluid are related to:

(1) the ability of drilling fluid to carry drill cuttings and clean the wellbore;
(2) suspending force;
(3) stabilizing effect on the wellbore;
(4) optimization design of drilling parameters.
 

Analysis

The rheological properties of high-purity polyanionic cellulose vary across different drilling fluid systems. For specific drilling fluid systems, assessing its impact solely based on viscosity may lead to significant biases. For instance, in seawater drilling fluid systems, the high salt content results in high viscosity, but the low degree of substitution leads to low salt resistance, resulting in poor thickening effects during use. This leads to low apparent viscosity, low plastic viscosity, and low dynamic shear force, consequently reducing the fluid's ability to carry drill cuttings, and in severe cases, potentially causing stuck pipe.