The South African pet care industry has expanded steadily over the past decade, driven by increasing urbanisation and the humanisation of pets. Among the many litter formulations on the market, gypsum-based cat litter is gaining ground because of its excellent moisture absorption, natural odour control, and clumping performance. Gypsum, or calcium sulphate dihydrate, is abundant in South Africa, with deposits in the Western Cape, Northern Cape and Limpopo, as well as synthetic gypsum from flue-gas desulphurisation plants. To convert this raw material into a competitive cat litter product, a reliable and efficient grinding system is essential, particularly when the target fineness is 150 mesh.
Shanghai Zenith Machinery Co., Ltd. has established itself as a leading manufacturer of ore grinding equipment in China. With decades of experience in powder engineering, Zenith offers a complete range of mills that can process gypsum into precisely controlled particle sizes. For cat litter producers in South Africa, Zenith’s MTW Trapezium Grinding Mill and YGM Raymond Mill represent two robust solutions for achieving 150 mesh gypsum powder at commercial scales.
In the cat litter industry, particle size is a critical quality parameter. A 150 mesh gypsum powder corresponds to a nominal particle diameter of approximately 100 microns. This fineness offers a perfect balance between surface area and bulk density. When gypsum is ground to 150 mesh, it absorbs urine quickly, forms compact clumps around waste, and releases ammonia less aggressively than coarser powders. The increased surface area also helps trap odours and maintain a dry, comfortable environment for the animal.
Moreover, 150 mesh gypsum is an ideal intermediate for producing litter granules. After grinding, the powder can be mixed with binders, water and additives, then granulated and dried into hard, low-dust pellets. Alternatively, a fine powder can be agglomerated with proprietary clumping agents. In every case, the mill must deliver a consistent particle size distribution without excessive ultrafine dust or oversized grains. A well-calibrated grinding mill, such as Zenith’s MTW series, ensures that the bulk of the product remains within the desired 150 mesh range, reducing rejects and increasing yield.
From an economic perspective, grinding to 150 mesh does not require the energy-intensive ultra-fine milling needed for 800 mesh powder. This means higher throughput, lower power consumption and longer equipment service life. For a South African plant with moderate electricity prices and unreliable power supply, the ability to produce high-value cat litter with low specific energy is a major competitive advantage.
The gypsum beneficiation route begins with crushing. Run-of-mine gypsum often contains lumps as large as 300 mm or more. A jaw crusher or hammer crusher in the front line reduces the material to below 30–50 mm, the maximum feed size accepted by a medium grinding mill. Following primary crushing, a vibrating feeder conveys the material to the mill. Magnetic separation and screening can remove tramp metal and impurities, protecting the grinding chamber.
Within the grinding mill, gypsum is subject to repeated impact, extrusion and abrasion. The powder is swept upward by air flow and transported to a cyclone and bag filter. The classifier adjusts the rotational speed and airflow to retain particles above 150 mesh for regrinding, while the finished powder is collected for storage or direct utilisation. If the gypsum is too moist, an air-swept dryer or mill with integrated hot-air inlet is necessary. With moisture levels lower than 6%, most conventional mills can operate smoothly.
However, gypsum has a unique thermal characteristic. If the temperature inside the mill exceeds 150°C, gypsum begins to lose its water of crystallisation and converts into hemihydrate (plaster of Paris). This can alter the hydration behaviour and clumping properties of the final litter. Therefore, the grinding system must control temperature through adequate ventilation and avoid excessive recirculation of hot air. Zenith’s mills are designed with high-volume air flow and efficient classification, which helps dissipate heat and keep the gypsum stable.
Zenith offers a comprehensive array of grinding equipment. For gypsum cat litter powder at 150 mesh, the two most appropriate choices are the MTW Trapezium Grinding Mill and the YGM Raymond Mill. Both can be equipped with classifiers and auxiliary equipment to produce a tightly controlled 150 mesh product.
The MTW trapezium mill is regarded as the flagship grind for medium and large capacity mineral powder plants. With multiple patented technologies, it has a compact structure, long service life, and an environment-friendly design. The machine uses a bevel gear transmission, an oil-lubricated internal system and a curved air duct. Its final product size can be adjusted between 1.6 and 0.045 mm, which comfortably includes 150 mesh (approximately 0.1 mm).
For a typical cat litter plant in South Africa, the MTW110 or MTW138 model is an ideal match. Even the smaller MTW110 can produce 3 to 9 tonnes per hour at the required fineness, which is enough for a medium-scale packaging line. The larger MTW138 offers 6 to 17 tonnes per hour for companies that plan to expand into regional export markets. If the operation is large, the MTW175G and MTW215G can produce up to 25 and 45 tonnes per hour respectively, while still holding the final size at 0.045–1.6 mm. The following table lists the main technical parameters of the MTW 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 cat litter producers, the MTW series also offers low energy consumption and a compact footprint. Its internal classifier can be tuned to maintain a D50 around 100 microns, ensuring that the 150 mesh standard is consistently met. The mill is also easy to operate with PLC control, reducing the need for highly skilled labour, which is valuable in remote mining and rural areas of South Africa.
If the capital budget is limited or the required output is below 10 tonnes per hour, the Zenith YGM Raymond Mill provides a proven and economic alternative. This classic mill is beneficial for energy saving and environmental protection, with high grinding efficiency and lower energy consumption. It is widely used by small and medium-sized gypsum suppliers. For 150 mesh gypsum powder, the YGM9517 model, with four grinding rollers and a maximum feed size of 25 mm, can produce 2.1 to 8 tonnes per hour.
| Model | Roller Quantity (pcs) | Max. Feed Size (mm) | Discharging Size (mm) | Capacity (t/h) |
|---|---|---|---|---|
| YGM8314 | 3 | 20 | 1.6-0.045 | 1.2-4.6 |
| YGM9517 | 4 | 25 | 1.6-0.045 | 2.1-8 |
| YGM4121 | 5 | 30 | 1.6-0.045 | 5-11 |
The YGM Raymond Mill is a well-proven machine with simple construction and relatively low maintenance. It can be installed outdoors under a simple sunshade, which suits typical South African climatic conditions. In addition, its dust-collection system meets modern environmental requirements, an important factor when operating near residential areas.
The selection of a grinding mill should be based on the raw material size, moisture, desired capacity, available power, and total cost of ownership. For a project aiming at a 150 mesh cat litter product, Zenith recommends first conducting a material test using a sample of the actual gypsum. This confirms grindability and helps determine the most energy-efficient option. In general, the MTW110 and MTW138 are the best sellers for African mineral grinding projects because they balance capacity, mechanical structure and ease of installation.
It is also important to design the complete system, not just the mill. The feeding hopper, vibrating feeder, screw conveyor, bucket elevator, dust collector, roots blower, and control cabinet must be matched to the mill’s performance. A poorly designed auxiliary circuit can reduce the mill’s actual throughput by as much as 20%. Zenith offers a complete production line solution, from crushing to packing, and can supply engineering support, installation supervision, and commissioning services across South Africa.
Furthermore, environmental compliance is essential. The South African Department of Forestry, Fisheries and the Environment enforces air quality standards for particulate matter. A baghouse filter with high collection efficiency should be installed. Zenith’s mills can be seamlessly integrated with efficient pulse dust collectors, ensuring that the emission level remains below the required limits and that the surrounding community is protected.
Gypsum-based cat litter is an emerging product in the South African pet care market, and 150 mesh is an ideal particle size for clumping and odour control. With the right grinding equipment, a producer can convert locally available natural gypsum or FGD gypsum into a premium litter product. Shanghai Zenith Machinery Co., Ltd. offers both the advanced MTW Trapezium Grinding Mill and the proven YGM Raymond Mill for this application. These machines provide high capacity, low energy consumption, long service life, and precise final-size control. By partnering with Zenith, South African manufacturers can establish a reliable, cost-effective and environmentally responsible gypsum powder production line capable of capturing the growing demand for quality cat litter.
