Product Details

Ultrafine Calcium Carbonate

1. Product Overview

Ultrafine Calcium Carbonate is a high-performance mineral additive widely used in oil and gas drilling fluids. With carefully graded particle sizes, it serves as a weighting, bridging, and fluid-loss control agent. It works synergistically with bentonite and other additives to improve mud cake quality, stabilize wellbore walls, and protect reservoirs, making it an essential material for both conventional and complex formation drilling operations.

2. Appearance & Technical Specifications

Core Technical Parameters

3. Core Functions

3.1 Improving Drilling Fluid Rheology & Suspension

By optimizing particle distribution, it enhances the rheological properties of drilling fluids, improving cuttings-carrying capacity and reducing the risk of sag or settling, thereby increasing overall drilling efficiency.

3.2 Forming Filter Cake & Stabilizing Wellbore

It strengthens the wall-building ability of the mud, forming a robust, low-permeability filter cake that effectively prevents wellbore collapse and fluid loss, ensuring safe and stable drilling operations.

3.3 Bridging & Reservoir Protection

Its multi-grade particle sizes form a temporary sealing layer on the formation face, reducing fluid invasion into the reservoir. The seal can be easily removed during production, minimizing formation damage.

3.4 Lubrication & Filtration Control

It improves the lubricity of the filter cake, reducing friction between the drill string and the borehole wall. At the same time, it acts as a filtration agent, helping to remove contaminants and maintain fluid cleanliness.

4. Product Application

Widely used in oil and gas exploration and development as a key additive for drilling fluid systems. Its main applications include:

· Enhancing cuttings-carrying capacity and improving drilling efficiency

· Forming high-quality filter cakes to prevent wellbore collapse

· Reducing fluid loss and providing temporary reservoir protection

· Used in combination with bentonite to optimize mud properties

· Suitable for both water-based and oil-based drilling fluid systems

5. Product Advantages

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

✅ Excellent Particle GradingMulti-grade particle sizes provide effective bridging and sealing for various formation pore sizes.

✅ Strong Impermeability & Wellbore StabilityForms a low-permeability filter cake to prevent collapse and ensure drilling safety.

✅ High-Temperature ResistanceMaintains stable performance under high-temperature conditions, ensuring consistent drilling fluid properties.

✅ Good CompatibilityCompatible with most common drilling fluid additives, with no adverse effects on mud rheology.

6. Packaging Specification

· Standard: 25 kg/bag in woven bags, paper-plastic composite bags, or bulk bags.

· Customizable packaging specifications are available according to client requirements.

7. Storage & Transportation

Store in a dry, cool, and ventilated warehouse during storage and transportation. Protect the product from moisture to prevent caking and maintain its free-flowing property.

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 solutions are available upon request.

Application Cases of Ultra-fine Calcium Carbonate for Drilling Fluids

1. Micro-nano Fracture Precise Plugging & Reservoir Protection Case for Shale Gas Horizontal Wells

Case Background: Shale gas reservoirs are characterized by dense micro-nano fracture groups, low formation permeability and weak pore structure. Conventional plugging materials have large particle size, which cannot effectively block tiny pore throats and micro-fractures, easily causing filtrate invasion, reservoir hydration damage and permeability reduction. It seriously affects later fracturing reconstruction and gas production capacity.

Application Formula & Dosage: On the basis of water-based drilling fluid system for shale gas, 2.0%–3.0% ultra-fine calcium carbonate with multi-stage particle grading was added. Combined with polymer plugging agents, it forms a micro-fracture graded sealing system to realize layered plugging of nano and micron fractures.

Application Effect: The ultra-fine particle size matches shale micro-fracture sizes accurately, which can quickly fill and seal micro-nano leakage channels, effectively reduce drilling fluid filtration and fluid loss. It optimizes filter cake structure to be thin, dense and smooth, significantly improving wellbore stability. The product is acid-soluble without residual blockage, and the core permeability recovery rate exceeds 92%, realizing high-efficiency plugging and low-damage reservoir protection.

2. Pressure-bearing Improvement Case for Fractured Formations in Tarim High-temperature Deep Wells

Case Background: Deep and ultra-deep wells in Tarim Basin have high formation temperature, developed multi-scale fractures and low formation bearing capacity. Conventional plugging materials are prone to thermal failure and poor filling compactness at high temperature, resulting in insufficient formation pressure-bearing capacity, which cannot meet the pressure test requirements before cementing and easily induces cementing leakage risks.

Application Method & Dosage: Multi-mesh compound ultra-fine calcium carbonate (800/1500/3000 mesh graded proportioning) was applied at 2.5%–3.5% in high-temperature resistant drilling fluid systems. It cooperates with high-temperature anti-sloughing agents to build a high-temperature stable graded plugging system.

Application Effect: The product features high temperature resistance, stable particle activity and excellent deformation filling performance. It forms a high-compactness plugging layer in multi-scale fractures, effectively improving the overall formation pressure-bearing capacity by 3–5 MPa. It eliminates hidden dangers of high-pressure leakage during cementing, ensures smooth cementing operation, and significantly improves the one-time qualification rate of deep well cementing quality.

3. Micro-leakage Control Case for Overseas Carbonate Reservoirs

Case Background: Carbonate reservoirs in overseas oilfields such as Iraq are developed with abundant dissolved pores and micro-fractures, with frequent low-speed percolation and micro-leakage during drilling. Traditional bridge plugging materials have large particle gaps, poor fine sealing effect, long-term minor leakage, high drilling fluid consumption and increased drilling costs.

Application Dosage: 2.0%–3.0% ultra-fine calcium carbonate was added to the field water-based drilling fluid system, used in combination with fibrous plugging materials to form rigid-flexible composite graded plugging structure.

Application Effect: Ultra-fine calcium carbonate fills the tiny gaps of conventional bridging skeleton, realizing full-scale sealing of macro-pores, micro-pores and micro-fractures. It thoroughly solves the persistent micro-leakage problem of carbonate formations, reduces drilling fluid consumption by more than 40%, and stabilizes wellbore quality. It has no adverse effect on logging interpretation and reservoir evaluation, fully meeting overseas high-standard drilling requirements.

4. Filter Cake Optimization & Anti-sticking Case for Changqing Tight Oil Horizontal Wells

Case Background: Tight oil horizontal wells in Changqing Oilfield have long horizontal sections, long-term open-hole soaking time and high drilling friction torque. Conventional drilling fluids form thick and rough filter cakes, which easily cause differential pressure stuck pipe, high drag and difficult tripping, restricting efficient drilling of long horizontal sections.

Application Method & Effect: The product is applied at a dosage of 2.0%–2.5%. The ultra-fine spherical particles can optimize the micro-morphology of filter cake, make the mud cake thin, dense and smooth, and effectively reduce downhole friction and torque. It significantly reduces the risk of differential pressure stuck pipe, improves the lubricity of the wellbore, ensures smooth tripping and casing running, and greatly improves the construction efficiency of horizontal wells.

5. Acid-soluble Low-damage Drilling Case for Low-permeability Gas Reservoirs

Case Background: Low-permeability gas reservoirs have fine pore throats and low formation bearing capacity. Insoluble plugging materials are easy to deposit and block pore throats, causing permanent reservoir damage, reducing gas reservoir permeability and seriously affecting single-well gas production.

Application Method & Effect: Conventional dosage is 2.0%–3.0%. Ultra-fine calcium carbonate has excellent acid-soluble characteristics, which can effectively plug micro-pores and micro-fractures during drilling to prevent leakage and stabilize wellbore. After well completion, it can be completely dissolved by acidizing treatment without residual blockage. It features low reservoir damage and high permeability recovery rate, which is the ideal low-damage plugging material for fine pore throat gas reservoirs.