PAC
POLYANIONIC CELLULOSE PAC – LV & PAC-HV
Polyanionic Cellulose (PAC) is a water-soluble polymer derived from cellulose, representing a chemically modified form of natural cellulose. This white to light-yellow powder or particle exhibits water resistance, preventing fluid loss in mud, and offers both low and high viscosity properties, enhancing its quality, especially in drilling applications.
PAC’s molecular structure is akin to carboxymethyl cellulose (CMC), but it surpasses CMC in filtration reduction, anti-salt, anti-collapse, and high-temperature resistance. Its excellent thermal stability, salt resistance, and potent antibacterial activity contribute to its effectiveness. PAC is easily soluble in both cold and hot water, with a usability range extending up to 150°C.
Widely utilized in oil drilling, especially in salt wells and offshore operations, PAC is a crucial component of drilling fluids. Its slurry showcases superior capabilities in reducing fluid loss, rejecting impurities, and withstanding higher temperatures, making it indispensable in various applications within the oil drilling industry.
Polyanionic cellulose (PAC), referred to as PAC, is a water-soluble cellulose ether derivative made from chemical modification of natural cellulose. Its appearance is white powder, odorless and tasteless. It has no pharmacological effects, is non-toxic and is harmless to living things. Its chemical structure contains a large number of negatively charged carboxyl groups, sulfonic acid groups, etc., so it has good water solubility and hydrolyzability, and can form a colloidal solution in water.
APPLICATION OF OF PAC
Polyanionic Cellulose (PAC) is a highly versatile organic chemical with diverse industrial applications.
Its primary uses and notable strengths encompass:
- Fluid-Loss Reduction: PAC serves as a crucial fluid-loss reducer in water-based drilling fluids.
- Drilling Fluid Additive: Widely employed as an additive in drilling fluids, PAC enhances their performance.
- Mud-Bit Cooling and Lubrication: It contributes to the cooling and lubrication of the mud-bit during drilling operations.
- Formation Cuttings Suspension: PAC aids in the effective suspension of formation cuttings.
- Mud Viscosity Adjustment: Utilized for adjusting mud viscosity levels to optimal specifications.
- pH Level Modification: Forms a component of mixtures aimed at modifying pH levels.
- Surface Transportation Facilitation: Assists in the efficient transportation of the surface and manages formation pressure in oil wells.
- Well Collapse Prevention: Its application helps prevent well collapse during drilling activities.
- Turbulence Scale Management: Used to control turbulence scale, minimizing pressure loss in reverse-flow systems.
Polyanionic cellulose (PAC) has important applications in oil drilling. There are some differences in the use of high viscosity and low viscosity polyanionic cellulose
Polyanionic cellulose with high viscosity has the following uses in oil drilling:
(1) Increased mud viscosity: helps stabilize the well wall, prevents wall collapse, and provides good wall protection for the drilling process.
(2) Improved mud carrying capacity: Mud can carry cuttings more efficiently, keeping the bottom of the well clean.
(3) Enhance the suspension stability of mud: prevent solid particles from settling and ensure the stability of drilling fluid properties.
Low-viscosity polyanionic cellulose also plays an important role in oil drilling:
(1) Improved mud rheology: Makes mud easier to pump and circulate, increasing drilling efficiency.
(2) Acts as a fluid loss reducer: reduces mud filtrate loss and maintains wellbore stability.
(3) Synergies with other treatment agents: Better regulate mud performance to meet the needs of different drilling conditions.
USES OF POLYANIONIC CELLULOSE (PAC)
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PAC-HV: Specifically designed for water-based drilling fluids, PAC-HV plays a pivotal role in reducing the filtration rate in various water-based oil and gas drilling fluids. Moreover, it proves valuable in enhancing and stabilizing viscosity, thereby contributing to improved hole cleaning and suspension properties across a diverse range of fluid environments.
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PAC-LV: Tailored for use in solids-laden, water-based drilling fluids, PAC-LV effectively mitigates the filtration rate in numerous water-based drilling fluids. Notably, it achieves this without inducing significant increases in viscosity or gel strength, making it a versatile solution for drilling operations.
In the realm of oil drilling, Polyanionic Cellulose (PAC) emerges as a cost-effective and versatile additive. It proves highly effective in mitigating the API filtration rate in a diverse array of water-based drilling fluids, encompassing fresh water, seawater, saturated saltwater, solids-free brines, native mud, flocculated mud, inhibited mud, and contaminated systems.
Moreover, PAC serves a dual purpose by enhancing and stabilizing viscosity. This improvement, in turn, positively impacts rheology, wellhole cleaning, and suspension properties. PAC achieves this by forming a protective coating and encapsulating cuttings and solids present in drilling fluids.
One of PAC’s notable attributes is its efficacy across a broad range of pH environments. It not only lubricates solids within the system but also enhances wall cake characteristics. Importantly, it plays a pivotal role in reducing the potential for pipe sticking, contributing to the overall efficiency and success of oil drilling operations.
PROCEDURES AND PREPARATION OF PAC
For optimal handling, store PAC in a dry environment. When introducing it to the mud system, use a hopper, adding less than two sacks per hour to prevent lumping.
During the handling of PAC, individuals should adhere to safety guidelines by wearing appropriate Personal Protective Equipment, including dust masks and eye protection, especially when dealing with powdered products.
Exercise caution to avoid skin contact, and take measures to prevent inhalation of dust or any contact with the eyes. Prioritize safety protocols to ensure a secure working environment.
APPLICATION OF PAC ( POLYANIONIC CELLULOSE ) IN OIL DRILLING FLUID
Due to excellent thickening, stabilizing, suspending properties and resistance to high temperature, PAC is widely used in the oil drilling fluid. Polyanionic Cellulose is more suitable for offshore drilling and the functions of Polyanionic Cellulose in drilling fluid are listed as below.
1). The drilling mud is the suspended matter of solids in the aqueous solution, and the same as other colloidal suspension dispersions, so has a certain life period. Polyanionic Cellulose can keep it stable and then prolong its life period. It has more obvious effects especially in mud suspension dispersions with dissolving salt.
2). The drilling mud with Polyanionic Cellulose can form thin and solid shaft wall as well as filter cake with low permeability, and thus can reduce the hole shrinkage and collapse phenomena resulting from water loss of mud.
3). The mud with the addition of Polyanionic Cellulose is seldom affected by mycete, so it doesn’t need to maintain high pH value or use preservatives. It can still keep stable with corresponding decrease of the usage amount of other chemical agents, or even within a certain range of temperature variation during the drilling process.
4). The mud with Polyanionic Cellulose enables the drilling machine to obtain low initial gel strength, so the mud can discharge air in it easily and discard debris in a mud pit quickly. PAC-HV applies to the mud with smaller proportion and a small usage amount can increase viscosity and reduce fluid loss. A small amount of Polyanionic Cellulose can replace a lot of clay and this kind of mud can reduce the difficulties resulting from encountering CaSO42H20 or CaSO4 salt belt during drilling process. However, PAC-LV applies to the mud with larger proportion, can reduce the fluid loss but have little effect on the viscosity. In use, Polyanionic Cellulose should be dissolved in water to prepare the solution (usually 1/40-1/20) and then add into the mud. Polyanionic Cellulose can also be compounded with other chemical agents to add into the mud.
PACKING OF POLYANIONIC CELLULOSE
PAC Polyanionic cellulose can supply with 25 kg bag. It can also depend on the customer request. For 20 Ft container 15 MT with 10 pallets and 40ft container can load with 25 MT with 20 pallets.
(1) Ensuring Safety:
The packaging materials we choose that can withstand various physical and chemical challenges encountered during long-distance transportation, including drops, pressure, and changes in temperature and humidity. For hazardous chemicals that are flammable, explosive, toxic, or corrosive, special safety packaging will be used to ensure compliance with the United Nations “Recommendations on the Transport of Dangerous Goods: Model Regulations” (also known as the UN regulations).
(2) Leakage Protection:
Our packaging will include enhanced measures to prevent leakage, especially for liquids or chemicals that can produce harmful vapors. This will be achieved through the use of double-layer packaging or special sealing techniques to provide additional safety assurance.
(3) Clear Label Information:
We will ensure that correct labeling information is clearly marked on the packaging, including product name, hazardous material identification, batch number, manufacturer information, etc. Hazardous materials will be labeled with the appropriate hazard labels and UN numbers in accordance with international regulations such as the IMDG Code (International Maritime Dangerous Goods Code) or ICAO TI (International Civil Aviation Organization Technical Instructions).
(4)Environmental Protection Factors:
Our packaging will take environmental impact into consideration. We will use recyclable or biodegradable materials as much as possible, avoid excessive packaging, reduce waste and costs, and adhere to the principles of sustainable development.
TECHNICAL DATA SHEET OF PAC
| TEST ITEM | STANDARD | STANDARD | |
|---|---|---|---|
| PAC-LV | PAC-HV | ||
| Appearance | Freely flowable powder | Freely flowable powder | |
| pH value | 6.0-8.0 | 6.0-8.0 | |
| Purity, % | 95 Min | 95 Min | |
| Moisture, % | 10 Max | 10 Max | |
| D.S. | 0.90 Min | 0.90 Min | |
| Viscosity Brookfield 1% | 50 Max | 1500 Min | |
| API Fluid Lose | Increase 0.57% | 25.0ml Max | 20.0ml Max |
| API Fluid Lose | Increase 0.86% | 15.0ml Max | 15.0ml Max |
| API Fluid Lose | Increase 1.14% | 10.0ml Max | 10.0ml Max |
| YP Value | Increase 0.57% | 0.5 Max | 2.4 Min |
| YP Value | Increase 0.86% | 1.0 Max | 9.6 Min |
| YP Value | Increase 1.14% | 1.5 Max | 19.2 Min |
