Product Details

Hydrolyzed Polyacrylonitrile Ammonium Salt (NH₄-HPAN)

1. Product Overview

Hydrolyzed Polyacrylonitrile Ammonium Salt (NH₄-HPAN) is a high-performance, multi-functional drilling fluid additive synthesized by degrading polyacrylonitrile under high temperature and pressure. With excellent fluid loss control, shale inhibition and wellbore stabilization properties, it is widely used as a fluid loss reducer and shale stabilizer in oil and gas drilling operations, especially suitable for high-salinity and easily collapsed formations.

2. Appearance & Technical Specifications

Core Technical Parameters

Drilling Fluid Performance

3. Core Functions

3.1 Fluid Loss Reduction

NH₄-HPAN significantly reduces drilling fluid filtration loss, with enhanced effectiveness under high-temperature and high-pressure conditions. It minimizes fluid loss during drilling, stabilizes wellbore walls and prevents formation collapse.

3.2 Anti-Collapse & Wellbore Stabilization

With embedding and inhibition effects on shale, NH₄-HPAN provides excellent borehole stabilization. It effectively prevents wellbore collapse in high-salinity formations, ensuring the integrity of the wellbore throughout drilling operations.

3.3 Salt Resistance

NH₄-HPAN has strong salt tolerance and remains stable in high-salinity environments without efficacy loss as salinity increases, making it particularly critical for treating high-salt formations.

3.4 Viscosity Regulation & Hydration Enhancement

Some grades of NH₄-HPAN can reduce fluid viscosity, minimizing drilling complications. The introduction of sulfonate groups enhances hydration ability and water-binding energy, further strengthening the wellbore and preventing collapse and sticking.

4. Product Application

NH₄-HPAN is widely used in drilling fluid systems as a fluid loss reducer and shale stabilizer. Typical applications include:

· Reducing high-pressure fluid loss and improving filter cake quality

· Inhibiting shale hydration and swelling to prevent borehole collapse and sticking

· Enhancing cementing quality and reducing overall drilling costs

· Compatible with various drilling additives, with typical dosages of 0.5%–1.5%

· Suitable for high-salinity and complex formation drilling operations

5. Product Advantages

✅ Strong Inhibition & Wellbore StabilizationExcellent shale inhibition and anti-collapse performance, effectively preventing borehole instability issues.

✅ Environmentally CompliantNon-toxic and pollution-free, meeting environmental protection requirements for drilling operations.

✅ Efficient Fluid Loss ControlSignificantly reduces filtration loss under high-temperature and high-pressure conditions, improving filter cake quality.

✅ Excellent Compatibility & Easy ApplicationCompatible with various drilling fluid additives and water-based mud formulations, with simple and convenient on-site use.

6. Packaging Specification

· Standard: 25 kg per bag in triple-layer composite kraft paper bags.

· Customized packaging specifications and materials are available upon request.

7. Storage & Transportation

Store in dry, cool and ventilated warehouses during storage and transportation. Keep away from fire and heat sources, and avoid direct sunlight. Moisture exposure does not affect product performance.

8. Disclaimer & Technical Support

All specifications and descriptions in this document are for reference only. The product shall be used in accordance with the customer’s actual working conditions and technical requirements. Customized formulations and professional technical solutions are available upon request.

Application Cases of Ammonium Hydrolyzed Polyacrylonitrile for Drilling Fluids

1. Strong Inhibition and Anti-sloughing Well Stabilization Case for Shale Formations

Case Background: The shallow and medium-depth shale formations in central and eastern oilfields are rich in hydrated montmorillonite, with strong water sensitivity and severe hydration expansion and spalling. Conventional drilling fluid systems have weak inhibition performance, prone to wellbore enlargement, hole collapse and cuttings balling during fast drilling, resulting in poor wellbore quality, increased tripping resistance and delayed drilling cycle.

Application Formula & Dosage: On the basis of conventional water-based drilling fluid system, 1.5%–2.5% ammonium hydrolyzed polyacrylonitrile was added as the main inhibitor and filtration reducer. It forms a high-efficiency inhibition and anti-sloughing system cooperating with potassium salt additives.

Application Effect: The product has excellent clay hydration inhibition performance. Its ammonium ions and polymer molecular chains can effectively embed and adsorb on clay lattice layers, inhibit water molecule penetration and clay hydration dispersion. It significantly reduces shale spalling and wellbore enlargement rate, keeps cuttings loose and clean without balling. The drilling fluid filtration performance is optimized, downhole complex risks are greatly reduced, and continuous and efficient fast drilling of water-sensitive shale formations is realized.

2.  Filtration Reduction and System Stabilization Case for Medium-low Temperature Sandstone Blocks

Case Background: Medium and shallow sandstone formations in Ordos and peripheral blocks have low formation temperature, developed pore permeability and poor original mud cake quality. Conventional single filtration reducers have limited control effect, large API filtration loss, serious filtrate invasion, and unstable drilling fluid rheology, which easily cause formation water swelling and wellbore instability, restricting safe and rapid drilling.

Application Method & Dosage: Ammonium hydrolyzed polyacrylonitrile was applied at 1.2%–2.0% in low-temperature water-based drilling fluid systems. It is compounded with bentonite and fluid loss additives to optimize mud cake forming performance and stabilize system rheological parameters.

Application Effect: The product has good low-temperature activity and excellent filtration control performance. It can form a dense and thin filter cake on the wellbore surface, effectively reduce API and medium-pressure filtration loss, and weaken filtrate invasion damage. It maintains stable viscosity and shear force of the drilling fluid system, improves wellbore self-stabilization ability, ensures smooth drilling of sandstone reservoirs, and effectively shortens single-well construction cycle.

3. Integrated Anti-salt and Anti-sloughing Case for Medium and Low Salinity Formations

Case Background: Partially saline and brackish water-bearing formations have certain ion interference and water-sensitive alternating layers. Conventional non-ionic treating agents are prone to performance attenuation under salt pollution, resulting in increased filtration loss, weakened inhibition, frequent local wellbore spalling and micro-leakage, and poor long-term system stability.

Application Dosage: 1.5%–2.2% ammonium hydrolyzed polyacrylonitrile was added to the brackish water drilling fluid system. Relying on its moderate salt resistance, it realizes integrated functions of anti-salt pollution, filtration reduction and wellbore stabilization.

Application Effect: The product has good medium salt resistance and ion interference resistance, no obvious performance degradation under low and medium salinity pollution. It can continuously maintain strong clay inhibition and excellent filtration control ability, effectively solve the problems of wellbore spalling and micro-leakage in salt-bearing alternating formations. The drilling fluid system has stable performance and strong adaptability, which ensures long-cycle safe drilling of complex saline interbedded formations.

4. System Optimization Case for Large-hole Fast Drilling in Shallow Formations

Case Background: Shallow large-open-hole drilling features fast footage speed, large cuttings discharge and severe formation hydration. Conventional drilling fluid systems have insufficient inhibition and poor filtration control, which easily cause cuttings deposition, wellbore shrinkage and collapse, low hole cleaning efficiency and restricted rapid drilling efficiency.

Application Method & Effect: Ammonium hydrolyzed polyacrylonitrile was applied at 1.3%–2.0% in large-hole shallow drilling fluid systems. It can quickly optimize the colloidal structure of the drilling fluid, improve suspension and cutting carrying capacity, reduce filtration loss, and inhibit formation hydration. It matches the high-efficiency drilling rhythm of shallow large holes, ensures clean wellbore and stable well wall, and significantly improves mechanical drilling speed.

5. Low-damage Reservoir Protection Drilling Case for Low-permeability Reservoirs

Case Background: Low-permeability oil and gas reservoirs have fine pore throats and fragile reservoir structures. Excessive filtration loss and unoptimized mud cake are easy to cause solid phase retention and pore throat blockage, resulting in reduced reservoir permeability and affecting later oil and gas development benefits.

Application Method & Effect: The conventional dosage is 1.2%–1.8%. Ammonium hydrolyzed polyacrylonitrile has good film-forming and plugging properties, which can optimize mud cake quality and reduce filtrate invasion during drilling. It effectively protects low-permeability reservoir pore throats, reduces reservoir hydration damage and solid phase blockage, and improves core permeability recovery rate. It features low comprehensive reservoir damage and excellent low-damage drilling effect, which is suitable for protective drilling of medium and low temperature low-permeability reservoirs.