1. Project Overview

1.1 Introduction to Pyrophyllite

Pyrophyllite is a hydrous layered aluminium silicate mineral with the chemical formula Al₂Si₄O₁₀(OH)₂, belonging to the clay mineral group. Its crystal structure is a 2:1 layered type, consisting of alternating aluminium‑oxygen octahedral and silicon‑oxygen tetrahedral sheets, offering high chemical and thermal stability. Pyrophyllite has a fine texture, low hardness (Mohs 1–2), a density of approximately 2.65–2.90 g/cm³, a smooth, soapy feel, and a waxy lustre. It exhibits high oil absorption, strong hiding power, excellent electrical and thermal insulation, and good volume stability at high temperatures, with a refractoriness exceeding 1700°C, making it an excellent industrial mineral raw material.

1.2 Project Background

As a multi‑functional non‑metallic mineral, pyrophyllite plays an important role in building materials, ceramics, chemicals, arts and many other fields owing to its outstanding physical and chemical properties. In recent years, with the rapid development of downstream industries such as fibreglass, refractories and ceramics, the demand for pyrophyllite powder has continued to grow. In 2024, China’s pyrophyllite production reached 8.353 million tons, with a demand of 8.073 million tons, showing a steady upward trend. With technological progress and industrial upgrading, the application fields of pyrophyllite are constantly expanding, and market demand continues to increase.

Pyrophyllite grinding is an important means of achieving high‑value utilisation of this resource. Through grinding, pyrophyllite can be converted into powders of various finenesses, meeting the application requirements of high‑value sectors such as ceramics, fibreglass, refractories, coatings, rubber and plastics.

1.3 Project Objectives

This plan aims to demonstrate the feasibility of building a pyrophyllite grinding production line. Through rational process design, equipment selection and market positioning, it will achieve efficient development and utilisation of pyrophyllite resources, meeting downstream market demand for pyrophyllite powders of different finenesses.

2. Product Plan

2.1 Product Positioning

Based on the different requirements of downstream applications, pyrophyllite grinding products can be divided into the following three grades:

Product Grade	Fineness Range	Target Market	Main Uses
Coarse powder	80‑200 mesh (74‑180 μm)	Refractories, ceramics	Refractory bricks, kiln furniture, ceramic bodies
Medium‑fine powder	200‑400 mesh (38‑74 μm)	Fibreglass, papermaking	Fibreglass raw material, paper filler
Ultra‑fine powder	325‑2500 mesh (5‑44 μm)	Coatings, plastics, rubber, chemicals	Functional fillers, catalyst carriers

2.2 Product Quality Standards

• Whiteness: ≥80% for general products; up to 96% after calcination
• Moisture content: Finished product moisture <1%
• Particle size distribution: Controlled D50 and D97 values according to different applications
• Purity: Depending on application, Al₂O₃ content of 18%–22% is preferred (for fibreglass)

3. Pyrophyllite Grinding Process

3.1 Process Flow Chart

Raw ore → Sorting / magnetic separation (impurity removal) → Jaw crusher (coarse crushing) →
Hammer/roller crusher (fine crushing) → Bucket elevator → Storage silo →
Electromagnetic vibrating feeder → Main grinding mill (Raymond mill / vertical mill / ultra‑fine mill) →
Classifier (air separator) → Cyclone collector → Pulse dust collector →
Finished product conveying → Finished product silo → Automatic packaging → Warehouse

3.2 Detailed Description of Each Stage

(1) Raw Ore Pre‑treatment

The mined pyrophyllite ore may contain harder impurities such as quartz and corundum. Sorting or magnetic separation before grinding is recommended to protect equipment and improve product purity. For products requiring high whiteness, flotation or chemical bleaching can also be combined for purification.

(2) Crushing Stage

Large pyrophyllite blocks are first coarsely crushed by a jaw crusher, then further crushed by a hammer or roller crusher to a particle size of 15–30 mm to meet the feed requirements of the grinding mill. Care must be taken during crushing to prevent hard impurities from entering and causing excessive wear.

(3) Elevating and Storage

The crushed qualified material is conveyed by a bucket elevator to a vibrating feeder or intermediate storage silo, ensuring continuous and uniform feeding. A belt weigher with speed control is usually installed below the silo to accurately control the feed rate and ensure stable system operation.

(4) Grinding Operation

Material is uniformly fed into the grinding chamber of the main mill, where it is crushed by compression and attrition between the grinding rollers and the ring (or between the table and rollers). A classifier is built into the main unit to achieve preliminary separation of coarse and fine particles. Oversized particles that do not meet fineness requirements fall back onto the grinding table for re‑grinding, forming an internal circulating system.

(5) Pneumatic Conveying and Classification

During grinding, an induced‑draft fan directs airflow to carry fine powders out of the chamber through pipelines into a cyclone separator or bag filter. In the airflow, powders of different particle sizes are precisely classified by the air classifier to ensure consistent product fineness.

(6) Finished Product Collection and Packaging

Qualified pyrophyllite powder is collected by the dust collection system, discharged through a rotary valve, and conveyed by a screw conveyor or bucket elevator to a finished product silo for temporary storage. According to customer requirements, automatic bagging machines or tanker loading can be used for quantitative packaging.

(7) Auxiliary Systems

The entire process is equipped with iron removal devices to prevent metallic contamination. Depending on the raw material moisture content, a drying system with a hot‑air furnace can be installed to ensure final product moisture below 1%.

4. Equipment Selection Plan

4.1 Main Equipment Selection

Based on capacity, fineness and process requirements, the commonly used equipment includes:

Equipment Type	Capacity Range	Product Fineness	Advantages	Suitable Application
Raymond mill	1‑50 t/h	38‑180 μm (80‑400 mesh)	High efficiency, stable operation, easy maintenance, low cost	Medium‑fine powder large‑scale processing
Vertical roller mill	1‑200 t/h	22‑180 μm	High grinding efficiency, high automation, environmental protection, low noise, strong drying capability	Large‑scale industrial production
Ultra‑fine vertical mill	1‑50 t/h	3‑22 μm (325‑2500 mesh)	Low energy consumption, high classification efficiency, low operating cost	High‑value ultra‑fine powder processing

4.2 Auxiliary Equipment Configuration

Equipment	Function	Remarks
Jaw crusher	Coarse crushing	Reduces bulk ore to <30 mm
Hammer/roller crusher	Fine crushing	Further reduces to feed size
Bucket elevator	Material conveying	Vertical transport of crushed material
Electromagnetic vibrating feeder	Uniform feeding	Controls feed rate
Classifier (air separator)	Particle size control	Ensures product fineness
Pulse dust collector	Dust collection	Meets emission standards
Iron removal device	De‑ironing	Prevents metallic contamination
Drying system	Moisture control	Controls raw material moisture

4.3 Selection Recommendations

• Annual capacity 10,000‑50,000 tons: Recommend Raymond mill (4R or 5R series) – moderate investment, good cost‑performance
• Annual capacity 50,000‑200,000 tons: Recommend vertical roller mill – high automation, clear economies of scale
• Ultra‑fine powder (>1250 mesh) high‑value products: Recommend ultra‑fine vertical mill

5. Application Scenarios after Pyrophyllite Grinding (Detailed Analysis)

After grinding, fine pyrophyllite powder finds extensive applications in various industrial sectors. The following is a detailed breakdown by field.

5.1 Fibreglass Industry (Largest Downstream Market, 72% Share)

Overview: Fibreglass is the largest downstream market for pyrophyllite, accounting for 72% of the total. China’s fibreglass output grew from 4.68 million tons in 2018 to 7.56 million tons in 2024, with a compound annual growth rate of 8.3%, making it the world’s largest fibreglass producer.

Specific applications:

• Used as the main silico‑aluminous raw material for fibreglass production; medium‑alumina pyrophyllite with Al₂O₃ content of 18%–22% is preferred
• Can replace aluminium powder to reduce costs, optimise the Al/Si ratio, and improve the mechanical strength of fibreglass
• Acts as a flux to help lower melting temperature and enhance fibreglass quality
• Widely used in electronic‑grade fibre production

Typical customers: Jushi Group, Taishan Fibreglass and other large fibreglass enterprises

Fineness requirement: Typically 200‑325 mesh

5.2 Refractory Industry

Overview: With a high melting point (refractoriness ≥ 1700°C), pyrophyllite is an excellent refractory raw material.

Specific applications:

• Refractory bricks: Improves thermal shock resistance, preventing cracking during rapid temperature changes
• Castables: Enhances flowability for easier forming
• Taphole clays: The micro‑expansion from high‑temperature phase transformation enhances furnace lining integrity
• Crucibles, kiln furniture: High temperature resistance and good thermal shock resistance
• New refractories: Can be mixed with other minerals to prepare new refractories such as mullite

Unique advantage: Low coefficient of thermal expansion effectively suppresses volume expansion at high temperatures, improving thermal shock resistance and service life.

Fineness requirement: Typically 80‑200 mesh (coarse powder) to 325 mesh (fine refractories)

5.3 Ceramics Industry

Overview: Pyrophyllite is widely used in the ceramics industry due to its high Al₂O₃ content, heat resistance and low shrinkage at high temperatures.

Specific applications:

• Domestic and architectural ceramics: Used as an auxiliary raw material to adjust body sintering properties
• Electrical porcelain and corrosion‑resistant ceramics: Reduces product deformation and cracking
• Ceramic bodies: Used as filler to reduce firing shrinkage, improve whiteness and smoothness
• Ceramic glazes: Improves thermal stability, reduces pinholes and deformation
• Sanitaryware, wall/floor tiles, glazed tiles: Effectively adjusts body shrinkage

Fineness requirement: Typically 200‑400 mesh

5.4 Coatings Industry

Overview: Pyrophyllite powder is an important functional filler in the coatings industry.

Specific applications:

• Architectural coatings: Partially replaces titanium dioxide as a whitening agent and functional filler
• Improves smoothness, hiding power, strength and insulation of coatings
• Emerging application as a coating raw material

Fineness requirement: Typically ≥325 mesh ultra‑fine powder

5.5 Plastics and Rubber Industry

Overview: Ultra‑fine pyrophyllite powder can serve as a functional filler in plastics and rubber.

Specific applications:

• Enhances heat resistance, insulation and mechanical strength of products
• Improves overall composite performance
• Used as filler and carrier in rubber products

Fineness requirement: Typically ≥800 mesh ultra‑fine powder

5.6 Papermaking Industry

Overview: Utilises pyrophyllite’s low hardness, easy pulverisation and chemical stability.

Specific applications:

• As paper filler and coating to improve density, whiteness, smoothness and printability
• Reduces production costs
• Enhances smoothness and hiding power of paper

Fineness requirement: Typically 325‑600 mesh

5.7 Synthetic Diamond and Superhard Material Synthesis

Overview: Pyrophyllite’s layered structure, low hardness and good electrical/thermal insulation make it an ideal pressure‑transmitting medium and sealing material for high‑pressure diamond synthesis.

Specific applications:

• In synthetic diamond manufacturing, it offers excellent hydrostatic pressure transmission and high‑temperature stability
• It is a key material in the static pressure synthesis process
• Also used as a pressure‑transmitting sealing medium in high‑pressure synthesis of cubic boron nitride and other superhard materials

Fineness requirement: High‑purity, specific particle‑size‑distribution fine powder

5.8 Chemical and Catalyst Fields

Overview: Pyrophyllite has broad application prospects in the chemical industry.

Specific applications:

• Catalyst carriers: Used in petroleum cracking and environmental catalysis
• Chemical adsorbents, additives, bleaching agents
• In metallurgy, used as foundry coating to prevent metal adhesion and improve casting surface finish
• In steelmaking, used as continuous casting mould flux as a lubricant and thermal insulation layer

5.9 Other Emerging Application Fields

Cosmetics and pharmaceuticals:

• High‑purity pyrophyllite used in talc powders and tablet excipients (requires strict purification)
• Used as a lubricant in confectionery and pharmaceuticals

Pesticide carriers: Used as carrier for insecticides

Waterproofing materials: Mixed with bitumen to make waterproofing membranes, improving weatherability

Carving and sculpture: High‑purity, aesthetically coloured pyrophyllite (such as Fujian Shoushan stone and Zhejiang Qingtian stone) is an ideal material for traditional seal carving and sculpture

6. Market Analysis and Outlook

6.1 Global Market Size

According to market research reports:

• The global pyrophyllite market reached US$619 million** in 2024 and is projected to reach **US$809 million by 2031, with a compound annual growth rate (CAGR) of 4.0%
• The global pyrophyllite market is expected to grow from US$79.21 million** in 2025 to **US$108.04 million by 2031, at a CAGR of 5.31%

6.2 China’s Market Position

• China is the world’s largest pyrophyllite market, accounting for approximately 89% of global share, followed by South Korea (4%) and Japan (2%)
• In 2024, China’s pyrophyllite industry market size reached RMB 3.657 billion, with an average market price of approximately RMB 453/ton
• China’s pyrophyllite output is expected to reach approximately 10.885 million tons by 2028

6.3 Segmental Market Structure

• By product type: Pyrophyllite micro‑powder is the largest segment, accounting for about 70%
• By downstream application: Fibreglass is the largest, accounting for 72%
• Other applications in order: refractories, ceramics, cement, etc.

6.4 Development Trends

1. Expanding application fields: With technological progress and industrial upgrading, pyrophyllite has broad prospects in environmental protection and new energy applications.
2. Clear trend towards high‑end products: Pyrophyllite applications are increasingly diversified in fibreglass, refractories, ceramics, rubber fillers and emerging functional materials.
3. Policy support: The state has classified “fibreglass and its products manufacturing” as a strategic emerging industry, indirectly supporting the pyrophyllite industry.

7. Investment Estimation and Economic Benefit Analysis

7.1 Reference Investment Scale

Based on industry reference data, investment scales for pyrophyllite processing projects vary significantly with capacity and process:

Project Scale	Total Investment Reference	Capacity Reference	Remarks
Small project	RMB 2 million	Annual 15,000 tons	Environmental investment approx. RMB 200,000
Medium project	RMB 12.67 million	Process‑dependent	Investment profit margin –4.11%
Medium project	RMB 18.53 million	Process‑dependent	Investment profit margin 37.15%
Large project	RMB 42.50 million	Process‑dependent	Payback period 3.91 years
Extra‑large project	RMB 78.57 million	Annual 600,000 tons	Investment profit margin 35.58%
Mega project	RMB 316.34 million	Annual 600,000 tons	Supporting project for Taishan Fibreglass

7.2 Cost Structure Analysis

Cost Item	Approx. Share	Description
Equipment purchase	40‑50%	Crushers, mills, classifiers, dust collectors, etc.
Civil engineering	20‑30%	Workshops, silos, foundations, etc.
Installation	10‑15%	Equipment erection, piping, etc.
Other expenses	10‑15%	Design, supervision, contingency, etc.

7.3 Benefit Analysis

Revenue sources:

• Pyrophyllite powder sales (main revenue)
• Differentiated pricing for products of varying fineness (ultra‑fine powders have higher added value)

Cost factors:

• Raw ore procurement
• Electricity consumption (grinding is the main power‑consuming step)
• Equipment maintenance and consumables (replacement of grinding rollers, rings, etc.)
• Labour costs
• Environmental facility operating costs

Breakeven point: Industry reference data show BEP typically between 30% and 42%

8. Risk Analysis and Mitigation Measures

8.1 Main Risks

Risk Type	Description	Impact Level
Market risk	Cyclical fluctuations in downstream fibreglass industry	High
Raw material risk	Pyrophyllite resources concentrated in Fujian and Zhejiang; supply stability	Medium
Environmental risk	Dust emissions, noise pollution and compliance requirements	Medium
Technical risk	Improper equipment selection affecting product quality and efficiency	Medium
Competitive risk	Established large enterprises already present (Jushi, Taishan, etc.)	High

8.2 Mitigation Measures

1. Market diversification: Do not rely solely on the fibreglass market; actively develop customers in refractories, ceramics, coatings, plastics and other sectors.
2. Raw material security: Establish long‑term relationships with mines, or consider acquiring mining rights.
3. Environment first: Select high‑efficiency pulse dust collectors to ensure dust emissions meet standards; optimise plant layout to reduce noise impact.
4. Careful equipment selection: Choose equipment precisely based on product positioning; request trial grinding with actual material from the supplier.
5. Differentiated competition: Target high‑value segments such as ultra‑fine powders to avoid low‑end homogeneous competition.

9. Conclusion and Recommendations

9.1 Feasibility Conclusion

The pyrophyllite grinding project is generally feasible, based on the following:

1. Solid resource base: China is the world’s largest producer and consumer of pyrophyllite, with abundant resources.
2. Strong market demand: Continuous growth in downstream industries such as fibreglass, refractories and ceramics drives demand for pyrophyllite powder.
3. Wide application fields: From traditional refractories and ceramics to emerging coatings, plastics and superhard materials, applications are constantly expanding.
4. Mature processing technology: Raymond mills, vertical roller mills and ultra‑fine mills are technically mature and can meet various fineness requirements.
5. Favourable policy environment: The state has designated fibreglass and related fields as strategic emerging industries.

9.2 Implementation Recommendations

Choose the appropriate plan based on target market:

• For fibreglass‑grade pyrophyllite powder (200‑325 mesh): Recommend vertical roller mill – high capacity, high automation, suitable for large‑scale industrial production. Focus on Al₂O₃ content (18%–22% preferred) and particle size uniformity.
• For refractory/ceramic powder (80‑200 mesh): Recommend Raymond mill – moderate investment, good cost‑performance, mature and reliable technology.
• For ultra‑fine high‑value products (>1250 mesh): Recommend ultra‑fine vertical mill – high product added value, but correspondingly higher investment.

General recommendations:

1. Market first: Before investing, consider signing agreements with downstream customers (especially fibreglass enterprises) to secure sales channels.
2. Phased construction: Consider starting with one medium‑sized production line and expanding after market stabilisation.
3. Focus on quality: Strictly control product whiteness, particle size distribution and purity to win market share through quality.
4. Green development: Equip with dust collection throughout the process to achieve clean production.
5. Technical cooperation: Maintain technical cooperation with equipment suppliers to continuously optimise process parameters.