Nigeria possesses large reserves of granite and other hard-rock aggregates, and the foundry industry is increasingly exploring the use of finely ground granite as a raw material for casting sand. A granite grinding mill, designed for continuous operation under demanding conditions, can convert granite rock, gravel, and quarry dust into a uniform 200 mesh powder that meets the particle-size requirements of many casting processes. This article offers a professional overview of granite grinding for casting sand in Nigeria, with a special focus on the 200 mesh specification, and recommends advanced grinding equipment from Shanghai Zenith Machinery Co., Ltd.
Shanghai Zenith Machinery Co., Ltd. is an excellent manufacturer of ore grinding equipment in China. The company has made great achievements in the field of ultra-fine powder grinding and is specialized in the research, development, and production of industrial powder grinding equipment. Its integrated solutions are being used in many countries and regions, including Nigeria, where stone processors and mining operators rely on Zenith mills for consistent powder production.
Casting sand, also known as foundry sand, is a critical material for making molds and cores. Its grain size directly affects the surface finish, gas permeability, and dimensional accuracy of the final casting. In many foundries, a 200 mesh product refers to powder that passes through a screen with 200 openings per linear inch, which means the particles are smaller than about 74 microns. This fine fraction is useful for facing sand, core sand, and additive applications that require a smooth mold surface and high refractoriness.
Granite powder contains quartz and feldspar, which give the material good thermal stability and resistance to high-temperature metal pouring. When granite is ground to 200 mesh, it creates angular particles that interlock well, helping to form stable molds. In Nigeria, there is a special interest in using granite grinding mill systems because granite is available in virtually every state and quarry waste is abundant. Instead of discarding crusher dust and screenings, processors can grind them into a valuable product for local casting factories.
Granite is one of the hardest and most abrasive materials in common use. Nigerian granite, often composed of quartz, feldspar, and mica, can cause rapid wear on conventional milling equipment. A grinding mill intended for granite must use abrasion-resistant parts and an efficient grinding mechanism to minimize maintenance interruptions.
There are also practical constraints that are common in Nigeria’s industrial environment. Electricity supply can be unstable, and operating costs are sensitive to power consumption. Therefore, the grinding solution should offer high energy efficiency and the ability to adjust output fineness without stopping the machine. Moisture can also be an issue, especially when quarry fines are exposed to rain. An ideal mill can handle small variations in moisture, or be combined with a drier in the grinding circuit.
When selecting a granite grinding mill for 200 mesh casting sand production in Nigeria, operators should evaluate the following criteria:
For processing granite into 200 mesh casting sand, Shanghai Zenith strongly recommends the MTW Trapezium Grinding Mill. This mill has multiple patents, a compact structure, a long service life, and an environmentally friendly design. It is particularly suited to hard materials such as granite because the grinding roller and ring are made of high-alloy wear-resistant materials. The trapezium-shaped grinding rings and rollers increase the contact area and improve the grinding efficiency.
The MTW mill can accept a maximum feed size of up to 50 mm and produce a final product between 1.6 mm and 0.038 mm. The 200 mesh target of 0.074 mm lies well within the mill’s operating range. The built-in high-efficiency classifier can be adjusted to make the finished powder finer or coarser without changing the basic mill configuration. This flexibility makes the MTW mill ideal for producers who want to serve both the casting sand market and other powder markets, such as ceramics and paint.
Table 1 provides the technical parameters of the MTW Trapezium Grinding Mill series.
| Model | Max. Feed Size (mm) | Final Size (mm) | Capacity (t/h) | Main Motor (kW) | Fan Motor (kW) |
|---|---|---|---|---|---|
| MTW110 | <30 | 1.6-0.045 | 3-9 | 55 | 55 |
| MTW110Z | <30 | 1.6-0.045 | 3-10 | 55 | 55 |
| MTW138Z | <35 | 1.6-0.045 | 6-17 | 90 | 110 |
| MTW175G | <40 | 1.6-0.045 | 9.5-25 | 160 | 200 |
| MTW215G | <50 | 1.6-0.045 | 15-45 | 280 | 315 |
For a Nigerian granite powder plant with a capacity target of 6 to 17 tonnes per hour, the MTW138Z is a balanced choice. If the project is expected to grow, the MTW175G offers a wider capacity range and a larger feed opening, making it easier to integrate with upstream jaw crushers and feeders.
For high-capacity plants in Nigeria that need to combine crushing, grinding, powder selection, drying, and material conveying in one machine, the LM Vertical Grinding Mill is an excellent alternative. The LM vertical mill integrates five functions into one compact unit, which reduces the floor area and simplifies the process flow. It is an eco-friendly production solution with high removal efficiency and low noise.
The Vertical Mineral Mill series produces powders with a fineness of 170-40 μm, which includes the 200 mesh range. The mill’s hydraulic system and grinding table provide strong grinding force suitable for hard granite. Table 2 shows the main technical parameters for the LM Vertical Mineral Mill series.
| Model | Plate Diameter (mm) | Capacity (t/h) | Output Fineness (μm) | Max Feed Size (mm) | Main Motor (kW) |
|---|---|---|---|---|---|
| LM130K | 1300 | 10-28 | 170-40 | <38 | 200 |
| LM190K | 1900 | 23-68 | 170-40 | <45 | 500 |
| LM280K | 2800 | 50-170 | 170-45 | <50 | 1250 |
The choice between the MTW and LM mills depends on the specific capacity and site layout. MTW mills are ideal for medium-capacity plants and have a simpler foundation. LM mills are preferred when the project needs to move large volumes of granite powder and has the electrical infrastructure to support high power motors.
To produce 200 mesh casting sand from granite in Nigeria, the complete process should include a jaw crusher or cone crusher to reduce rock to the mill feed size, a vibrating feeder, a bucket elevator, the grinding mill, a classifier, a dust collector, and a silo or packing line. Zenith can supply the complete line and support the design of the civil work.
Operators should also monitor the moisture content of the granite feed. If the moisture is above 6 percent, a hot-air drying system may be added before or during grinding. Metal detectors are recommended to remove steel fragments from crusher wear parts, which can damage grinding rollers. Regular inspection of the classifier blades and grinding rings will help maintain the 200 mesh fineness and ensure a long service life.
The demand for 200 mesh granite powder in Nigeria’s casting sand sector is expected to rise as foundries seek locally available raw materials and lower production costs. With a granite grinding mill from Shanghai Zenith, operators can transform granite waste into a high-value product with controlled fineness and stable quality.
Shanghai Zenith Machinery Co., Ltd. offers a complete range of grinding equipment, including MTW Trapezium Grinding Mill, LM Vertical Grinding Mill, Raymond Mill, Ball Mill, XZM Ultrafine Grinding Mill, and more. For granite-to-casting-sand projects in Nigeria, the MTW Trapezium Grinding Mill provides the best combination of capacity, precision, and energy efficiency. For larger operations, the LM Vertical Grinding Mill can be integrated as the core grinding equipment. Contact Zenith today for a custom solution tailored to your Nigerian granite project.
