Vietnam has become one of the most active cement production countries in Southeast Asia. Modern infrastructure projects and the continuous housing market have pushed cement output to high levels. Yet high output by itself is not sufficient in a competitive market. Cement producers are paying more and more attention to the quality of every additive. Gypsum is a crucial additive because it controls the setting time of concrete. A state of the art gypsum grinding mill for cement production in Vietnam is now expected to run reliably, consume less energy, and produce powder that meets strict fineness specifications. A growing number of projects specify 600 mesh for ultra-fine gypsum powder, especially when gypsum is ground in a separate preparation line before being blended into cement.
Gypsum is a hydrated calcium sulfate mineral used in cement plants around the world. In ordinary Portland cement manufacturing, clinker is interground with roughly 4 to 6 percent gypsum. Gypsum controls the reaction between tricalcium aluminate and water. Without gypsum, cement can flash set, which makes concrete impossible to place. Gypsum also affects early strength, drying shrinkage, and long-term durability. The particle size distribution of gypsum powder has a direct impact on its dissolution rate. A 600-mesh powder corresponds to extremely fine particles, about 20 to 25 micrometers in diameter, depending on the sieve standard. Cement producers often express the same specification as D97 at a value close to 23 micrometers, meaning that 97 percent of the particles are finer than that size. Such a fine powder dissolves more rapidly than standard 100-mesh or 200-mesh material, releasing sulfate ions evenly through the cement paste. This improves rheology, prevents abnormal setting, and reduces dosage fluctuations when gypsum is introduced as a separately prepared additive.
In Vietnam’s hot climate, strict setting control becomes even more difficult. A fine gypsum powder is a simple and effective tool for stable cement behavior. It is especially useful in blended cements containing fly ash, natural pozzolan, and limestone. Those supplementary materials change the ionic environment of cement hydration. Ultra-fine gypsum balances the system by providing a steady source of sulfate ions, which helps concrete admixtures perform predictably and reduces risks of slump loss and delayed hardening.
Grinding gypsum to 600 mesh is not as simple as grinding it to pass a coarse screen. The surface energy of the powder becomes very high, and fine particles tend to stick to mill internals. Gypsum also releases water of crystallization during over-grinding or when the mill temperature is too high. High humidity in the feedstock, especially in synthetic gypsum, causes caking and agglomeration. Ball mills can grind gypsum to cement fineness, but their efficiency drops sharply for products as fine as 600 mesh. Ordinary Raymond mills are not equipped with the high-speed dynamic classifier necessary to keep throughput high and avoid oversize particles. Without precise classification, a 600-mesh powder can contain a large proportion of oversize material. This problem cannot be solved by installing a finer screen because fine powders block screen openings. For continuous and economical production of 600-mesh gypsum, a vertical roller mill with hot gas drying and dynamic separation is the most suitable technology.
Shanghai Zenith Machinery Co., Ltd. is an excellent manufacturer of ore grinding equipment in China and has made major achievements in the field of ultra-fine powder grinding. The company is specialized in the research, development, and production of industrial powder grinding equipment and related devices. Zenith’s catalog includes MTW trapezium grinding mills, ball mills, MTM medium-speed grinding mills, Raymond mills, LM vertical grinding mills, LUM ultrafine vertical mills, XZM ultrafine grinding mills, and hammer mills. For a specialized gypsum grinding mill for cement production in Vietnam with a 600-mesh target, the LM series vertical fine-powder mill gives cement manufacturers a clear technical advantage.
The LM vertical fine-powder mill combines five process functions in one machine: crushing, grinding, powder selection, drying, and conveyance. Feed material enters the mill and falls on the center of the grinding table. The grinding rollers press the material from above. By the time the gypsum passes along the table edge, it is ground and partially dried by hot air. The gas sweeps the fine particles upward to the classifier. The classifier speed is adjusted so that particles finer than the selected limit can leave the mill, while coarse particles fall back to the table for regrinding. Because this is a closed-loop classification, the final product can be held steadily at 600 mesh. There is no need for a stand-alone dryer or screening machine, which considerably simplifies plant layout. LM vertical mills also have low energy consumption and a small footprint. For cement plants in Vietnam, where industrial land is often limited, this compactness can reduce foundation and erection costs.
The LM mill is particularly effective for gypsum because it grinds and dries the material in one air stream. This suits natural gypsum as well as desulfurization gypsum and phosphogypsum. Good sealing and negative-pressure operation prevent dust emission. Furthermore, the centrifugal force in the dynamic classifier gives a sharper particle distribution. A narrow distribution at 600 mesh means less risk of coarse gypsum islands in cement or building materials.
Based on the technical parameters published by Zenith, the two best suited models for 600-mesh gypsum powder are the LM130X-GX and LM220X-GX. The LM130X-GX has a grinding table diameter of 1300 mm, an output range of 4-12 t/h, and uses a 220 kW main motor. The LM220X-GX has a larger 2200 mm table, can reach 15-30 t/h, and is driven by a 560 kW main motor. Both models produce D97 fineness in the 325-600 mesh range. With proper adjustment of the classifier and grinding pressure, they can consistently deliver a final gypsum powder accepted as 600 mesh. For an existing cement plant or a compact new gypsum line, the LM130X-GX provides enough capacity and flexibility. For a high-capacity Vietnamese cement producer with several kiln lines, the LM220X-GX offers the lower specific energy and high throughput required in central grinding centers.
| Model | Plate diameter mm | Capacity t/h | Output fineness D97 | Main motor kW |
|---|---|---|---|---|
| LM130X-GX | 1300 | 4-12 | 325-600 mesh | 220 |
| LM220X-GX | 2200 | 15-30 | 325-600 mesh | 560 |
Actual productivity depends on the moisture and hardness of gypsum, as well as the target particle size. At the fine endpoint of 600 mesh, throughput is usually lower than at a coarse endpoint of 325 mesh. The figures in Table 1 should be used as a basis for preliminary selection. Zenith engineers can confirm the correct mill capacity for the exact feed material through ore tests and simulation.
The Vietnamese cement market is becoming more competitive, and gypsum grinding is one of the easiest ways to improve product quality. A dedicated gypsum grinding mill for cement production in Vietnam must be reliable, energy-efficient, and capable of maintaining a continuous 600-mesh output. Zenith’s LM130X-GX and LM220X-GX vertical fine-powder mills meet those requirements. They combine drying, grinding, classifying, and conveying in one piece of equipment. Their adjustable classifier allows precise product size control, and their robust vertical construction saves space and reduces civil works. By selecting a Zenith LM vertical mill, cement producers in Vietnam can secure a dependable and economical solution for high-quality 600-mesh gypsum powder, supporting better cement consistency for many years.
