Glass & ceramics
A source of CaO and MgO; chemistry and iron are often more important than extreme fineness.
DOLOMITE POWDER ENGINEERING GUIDE
Turning dolomite rock into a controlled industrial powder.
A process-led reference to geology, crushing, metered conveying, dry grinding, air classification and application-specific particle design, with CRGM80, CRGM100 and CRGM125 as the equipment platform.
- CaMg(CO3)2
- Double carbonate mineral
- 5-74 um
- CRGM catalogue product range
- 50+ years
- Manufacturing history
01Characterize feed
02Prepare a stable feed
03Control the PSD
04Verify the application
01 / Mineral fundamentals
Dolomite is a double carbonate with two process identities
Mineral dolomite has the ideal composition CaMg(CO3)2. In practice, ore may contain calcite, quartz, clay, iron-bearing minerals and organic matter. These variations affect whiteness, abrasion, acid reactivity, calcination behavior and final application value.
As a ground mineral, dolomite is used as a filler, extender, soil amendment and source of calcium and magnesium. As a thermally treated feed, it can be calcined or sintered for metallurgical fluxes, refractories and magnesium-bearing products. Powder specifications must therefore connect particle size with chemistry and the next unit operation.
Dolomite is common in sedimentary carbonate platforms and in some hydrothermal or metamorphic settings. It occurs in extensive belts in China, India, Southeast Asia, Europe, North America, Brazil, Mexico, Turkey, the Middle East and southern Africa.
02 / Global occurrence
Resources are widespread; comparable production data are not
Public statistics frequently combine dolomite with limestone, lime, dimension stone or crushed stone. This chart is a geological and industrial intensity guide, not a claimed world production-share table.
Method: qualitative synthesis of carbonate geology and industrial lime/dolomite reporting. Exact tonnage should be sourced by year, country and statistical category.
Resource is not specification
Two deposits with similar MgO may grind differently because crystal size, silica, micro-fractures and moisture change breakage and wear. Representative sampling and PSD testing are more useful than a country label.
Data note: A precise “global dolomite production” pie chart would imply a consistency that public datasets do not provide. For investment work, reconcile geological-survey, mining-license and lime-industry data under one stated definition and year.
03 / Powder design
Fineness follows function
Mesh is a convenient trade reference, but D10/D50/D90 or D97, oversize residue, brightness, oil absorption and chemistry are more reproducible.
| Planning band | Approx. opening | Typical uses | Why the size matters | What else to verify |
|---|---|---|---|---|
| 80-200 mesh coarse powder | 180-75 um | Soil conditioning, glass batch, basic construction blends, some flux feeds | High throughput and adequate mixing where ultrafine surface area is unnecessary. | CaO/MgO ratio, silica, iron, moisture, reaction or calcination behavior. |
| 200-325 mesh general industrial | 75-45 um | Mortar, wall putty, ceramics, agriculture, asphalt and rubber compounding | Better dispersion and packing while retaining economical grinding energy. | Coarse residue, whiteness, pH, grit and application-specific strength. |
| 400-800 mesh fine filler | 38-18 um | Paint, coatings, PVC, cable compounds, sealants and engineered stone | Higher surface area and lower top size improve film smoothness, packing and dispersion. | PSD span, oil absorption, brightness, moisture and surface-treatment compatibility. |
| 1000-1250 mesh ultrafine | 13-10 um | Higher-grade plastics, coatings, masterbatch, adhesives and specialty mineral blends | A controlled coarse tail helps surface finish and stabilizes rheology at higher filler loading. | D97, agglomerates, Fe contamination, particle morphology and dispersibility. |
| 1500-2500 mesh micronized | 8-5 um | Specialty fillers where validated surface area and top cut justify the added energy | Very fine particles influence opacity, interfacial area and formulation response. | Laser PSD, BET area, deagglomeration, economics and product performance. |
Construction
Particle packing, workability and cost control in putty, mortar and related blends.
Plastics & coatings
Fine PSD supports smoothness and dispersion; surface treatment may be evaluated for polymer systems.
Agriculture
Calcium and magnesium source and acidity management, subject to agronomic and regulatory analysis.
04 / Process engineering
Crushing prepares the mill. Conveying stabilizes it. Classification defines the powder.
A reliable line is a controlled loop rather than one standalone machine.
Feed testing
Measure mineralogy, CaO/MgO, silica, iron, moisture, hardness and required product tests.
Primary crushing
Jaw or impact crushing reduces run-of-mine rock. Screening controls the top size and rejects tramp material.
Metered conveying
A bin, feeder and enclosed conveyor deliver steady mass flow. Magnets protect downstream equipment.
Grinding
Rollers compress and shear particles against grinding rings. Circulating material receives repeated stressing.
Air classification
Rotor speed and airflow determine the cut point. Coarse particles return; acceptable powder moves onward.
Collection & packing
Cyclone and pulse collector recover product under negative pressure before silos, blending or packing.
CRGM grinding equipment in operationLocal project footage prepared for web delivery with Cronus identification.
ROM dolomite
→
Crusher & screen
→
Feed bin
→
CRGM mill
→
Classifier
→
Collector / silo
Optional drying, magnetic separation, surface treatment or multiple silos are inserted only when the feed and product specification require them.
Wet feed can coat the circuit and reduce classification efficiency. Stabilize moisture before fine grinding.
Quartz-rich feed increases abrasion and may restrict high-value filler applications.
Pressure, temperature and airflow affect conveying, cut size and dust collection at the same time.
Use representative, timed samples and a stated PSD method. A single sieve result is not a complete product definition.
05 / Equipment selection
Raymond mill, ball mill or CRGM ring roller mill?
Select by feed behavior, target PSD, contamination tolerance, plant scale and total operating strategy.
Conventional powder
- Common strength in roughly 80-400 mesh duties.
- Simple process arrangement and familiar maintenance.
- Well suited where a conventional sieve residue is acceptable.
- Capacity and efficiency decline as the requested top cut tightens.
Choose it when: moderate fineness, robust operation and a lower-complexity line matter most.
Flexible large circuit
- Broad feed and capacity flexibility with a separate classifier.
- Can produce fine powder with suitable classification.
- Requires grinding media management and a larger installation.
- Over-grinding, iron pickup and specific energy deserve testing.
Choose it when: existing infrastructure, very large scale or a specific impact/attrition profile supports the footprint.
Compact dry ultrafine loop
- Multi-stage compression and shear without a media charge.
- Integrated high-efficiency classification controls the coarse tail.
- Catalogue product range reaches 5-74 um, model dependent.
- Compact vertical process with centralized negative-pressure collection.
Choose it when: ultrafine dry powder, grade flexibility and tighter PSD control are central.
Mainly 80-325 mesh?Compare Raymond and CRGM using tested t/h, kWh/t, wear and residue.
D97 near 10 um?Prioritize classifier performance, airflow control and representative testing.
High quartz or iron?Review wear materials, contamination limits and possible pre-separation.
Multiple saleable grades?Plan recipes, cleaning, silos and sampling before sizing only the main mill.
06 / Working principle
Compression, shear and a continuous internal return
Prepared dolomite enters the grinding chamber through a controlled feeder. Rotation produces centrifugal force that loads the roller assemblies against the grinding rings. Particles are repeatedly compressed and sheared until airflow can lift them toward the classifier.
The dynamic classifier acts as the size-control gate. Fine particles pass with the process air to collection; coarse particles lose momentum and return to the grinding zone. This closed circuit avoids relying on a single pass and lets operators tune feed rate, airflow and classifier speed as one system.
01Multi-ring, multi-roller grinding zone
02Variable-speed dynamic classifier
03Negative-pressure pneumatic transport
04Cyclone and pulse dust collection
05Central lubrication and service access
06PLC-ready electrical control
07 / CRGM technical data
CRGM80, CRGM100 and CRGM125
Catalogue values are engineering references, not a dolomite performance guarantee. Chemistry, feed size, moisture, PSD and test method materially affect output.
Compact production
- Ring diameter
- 800 mm
- Rings / rollers
- 3 / 21
- Main shaft
- 230-240 rpm
- Product range
- 5-74 um
- Catalogue capacity
- 0.5-4.5 t/h
- Total power
- 143 kW
Balanced multi-grade line
- Ring diameter
- 1000 mm
- Rings / rollers
- 4 / 28
- Main shaft
- 180-200 rpm
- Product range
- 5-74 um
- Catalogue capacity
- 1.8-5 t/h
- Total power
- 244 kW
Higher-throughput platform
- Ring diameter
- 1250 mm
- Rings / rollers
- 4 / 32
- Main shaft
- 135-155 rpm
- Product range
- 7-74 um
- Catalogue capacity
- 1.5-12 t/h
- Total power
- 401 kW
| Parameter | CRGM80 | CRGM100 | CRGM125 |
|---|---|---|---|
| Maximum feed size | 20 mm | ||
| Overall dimensions (L x W x H) | 15.9 x 4.2 x 6.1 m | 19.7 x 4.7 x 7.7 m | 23.2 x 4.7 x 7.7 m |
| Main unit power | 75 kW | 132 kW | 185 kW |
| Classifier power | 18.5 kW | 30 kW | 75 kW |
| Blower power | 45 kW | 75 kW | 132 kW |
| Discharge valve | 0.75 x 2 kW | 1.1 kW | 1.5 kW |
| Screw conveyor | 3 kW | 4 kW | 4 kW |
Source: Cronus Grinding Mill Catalog, CRGM technical parameter tables. Confirm capacity with representative dolomite and an agreed product PSD and residue method.
08 / Practical advantages
Designed around stable powder, serviceable wear and a complete air circuit
Benefits become meaningful only when measured against the same feed, fineness and product test.
Controlled coarse tail
Dynamic classification returns oversize material rather than accepting a broad uncontrolled product.
No media charge
Rollers and rings form the primary wear system, avoiding continuous ball-media management.
Compact dry circuit
Grinding, lifting and classification are arranged vertically with enclosed pneumatic transport.
Multi-grade recipes
Classifier speed, airflow and feed rate can be recorded for repeatable grade changeovers.
Central dust control
Negative-pressure operation and pulse filtration support cleaner transfer and product recovery.
Project integration
Cronus can coordinate crusher, feeder, mill, collector, silo, packing and electrical scope.
09 / Project evidence
The line is proven in details that brochures rarely show
The local project photographs demonstrate manufacturing and installed mineral-grinding equipment. Final dolomite output must still be confirmed by a site-specific test.
What Cronus checks before a dolomite proposal
Feedchemistry, moisture, silica, top size
ProductPSD, residue, brightness, application
Plantpower, altitude, climate, layout
Economicshours, grades, packing, wear strategy
10 / Wear parts & spares
Matched parts protect both uptime and powder quality
Common service items include grinding rollers, rings, roller pins, shafts, classifier blades or impellers, liners, scrapers, seals, bearings, filter bags and pulse valves. Inspection frequency should follow vibration, power, pressure-drop and PSD trends rather than a calendar alone.
Cronus supplies OEM-matched dimensions and materials, with manufacturing support from the group's own casting and machining resources. The practical advantage is traceability: hardness, profile and fit are controlled against the machine instead of guessed from a photograph.
Roller & ringWear profile and hardness selection
Classifier partsCut-point and balance-critical components
Shafts & pinsMachined load-bearing parts
Filter & sealsAirflow, housekeeping and product recovery
11 / Company & manufacturing
Cronus brings Guilin Mining Machinery's manufacturing base to international projects
Cronus is a subsidiary of Guilin Mining Machinery, whose equipment manufacturing history began in 1973. More than five decades of casting, machining, assembly and field feedback support the grinding systems supplied today.
Capabilities cover mineral testing, process design, equipment manufacturing, installation guidance, commissioning and parts support. Company credentials include high-tech enterprise recognition, invention and utility patents, CE documentation and ISO management-system certification.
Established heritage: 1973High-tech enterpriseInvention patentsCE & ISO systems
International project and engineering team.
12 / Service lifecycle
From representative sample to repeatable production
Commissioning is complete when operators understand the process window, not merely when the motor starts.
Material review
Feed analysis, target PSD, product tests and representative sample planning.
Process definition
Flowsheet, model, utilities, dust control, layout and commercial scope.
Manufacturing QA
Fabrication, machining checks, assembly records and pre-shipment review.
Installation support
Foundation, alignment, piping, electrical and lubrication-system guidance.
Commissioning
No-load checks, controlled feed ramp-up, airflow balance and PSD recipes.
Training
Operation, sampling, maintenance, safety and troubleshooting documentation.
Parts planning
Recommended start-up spares and wear monitoring for the actual feed.
Remote follow-up
Trend review and process adjustment as ore or product requirements change.
Customers visit the factory to inspect the line, parts and test basis.Visits and video reviews can be arranged around the project stage.
13 / Engineering FAQ
Questions worth answering before selecting a mill
The short answer is often “test the representative feed.” These notes explain what the test should resolve.
What feed size should enter a CRGM dolomite line?
The catalogue states a maximum feed size of 20 mm. A narrower, stable top size is often preferable. Crusher selection depends on run-of-mine size, silica, moisture and desired capacity.
Does dolomite need drying before grinding?
Only when free moisture is high enough to cause coating, bridging or poor classification. Measure seasonal moisture and confirm the allowable value during testing.
What is the practical difference between mesh and microns?
Mesh relates to sieve opening; microns express particle size directly. Ultrafine powder should be specified by a full laser PSD and a stated D-value, not by mesh alone.
Can a Raymond mill produce 800-mesh dolomite?
Some systems may report fine fractions at that level, but stable capacity and coarse-tail control must be demonstrated. Ring roller or classified ball-mill circuits are normally compared for sustained ultrafine duty.
When is a ball mill the better option?
It can be sensible for very large plants, existing ball-mill infrastructure, wet processing or a product that benefits from its particular breakage mechanism.
How do I choose CRGM80, CRGM100 or CRGM125?
Use required capacity at the agreed PSD, feed properties, annual hours, grade mix, local power and layout. Nominal model size alone is not enough.
Can one line make several dolomite grades?
Yes, within the tested operating window. Each grade should have a recorded recipe for feeder rate, classifier speed, airflow and sampling, plus suitable silo and cleaning arrangements.
What most affects wear cost?
Quartz and other hard impurities, feed top size, target fineness, operating stability, material selection and inspection practice all matter. Test mineralogy before estimating wear life.
How is final fineness controlled?
The cut point results from classifier rotor speed, airflow, circulating load, feed rate and the grinding state. Operators tune the full loop rather than one control in isolation.
Can the line include crushing, conveying and packing?
Yes. Scope can cover crusher, screen, feeder, conveyor, mill, classifier, cyclone, dust collector, silos, packing and electrical control.
What data should be sent for a proposal?
Material name and assay, moisture, feed size, target PSD or residue, application, capacity, hours, voltage, altitude, climate, packing and site layout.
What after-sales support is available?
Documentation, installation guidance, remote or arranged site commissioning, operator training, process follow-up and original spare-part support can be included by project scope.
14 / Start with the material
Describe the powder your customer needs
Send the feed analysis and the downstream performance target. An engineering reply can then focus on the right test, circuit and model instead of a generic quotation.
Phone / WhatsApp+86 199 2122 1418Emailsales@shcronus.com
Shanghai officeRoom 801, Building 2, Shanghai Zhicheng, No. 8666 Hunan Highway, Pudong New Area, Shanghai, China