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⒈Deep dehydration of fine-grained flotation concentrate ⑴ Thermal pressure filtration and drying are used to reduce the moisture content of the flotation concentrate to below 13%, turning it into a completely dry, free-flowing material. This ensures that the product meets the required moisture specifications, improves its quality, and allows for maximum savings in railway and road transportation costs； ⑵For coking coal, fully reducing the moisture content of the coal means that for every 1% decrease in moisture, the lifespan of the coke oven increases by 6%, its capacity increases by 5%, and the coking time is reduced by 3% ； ⑶For injection coal and smelting coking coal, strict requirements are placed on moisture levels; reducing the moisture content of flotation coking coal to below 13% allows it to be sold directly as injection coal or smelting coking coal ； ⒉Deep dehydration of fine-grained raw coal slime or flotation tailings (1) Thermal pressure filtration and drying are used to reduce the moisture content of fine-grained raw coal slime or flotation tailings to below 13%, turning them into completely dry, granular material. This solves problems related to storage, handling, and transportation of such materials. They can be evenly mixed with washed middle coal or blended coal for sale, thereby transforming them from by-products of coal processing into marketable thermal coal, which brings significant economic and environmental benefits ； ⑵For virgin coal slime, the ash content is roughly the same as that of raw coal; the calorific value of the dried coal slime product is high, and when sold as thermal coal, it has no impact on the quality of such coal ； ⑶For flotation tailings, an excessively high flotation recovery rate results in low ash content and calorific value, leaving them with no other option but to be discarded as industrial waste. However, a high flotation recovery rate indicates a high recovery rate of clean coal in the coal processing plant as well as a high level of coal processing technology; yet it does not necessarily mean maximum economic efficiency for the entire plant. Therefore, it is appropriate to reduce the flotation recovery rate, lower the ash content in the tail coal, increase its calorific value, and use heat-pressure filtration and drying techniques to convert it into dry granular material with a moisture content of less than 13%, which can then be sold as thermal coal. In this way, industrial waste can be transformed into a commodity such as thermal coal, thereby compensating for the losses resulting from the reduced recovery rate of clean coal. A comprehensive comparison can then be made to achieve maximum economic efficiency for the entire plant. Moreover, for slurry-type coal, every 1% reduction in moisture content results in an increase in calorific value of 70–80 kcal/kg, which also helps to ensure the quality of the thermal coal product. ⒊Deep dehydration of mineral processing products Most mineral processing plants use wet grinding to thoroughly disintegrate the ore material, and then flotation is employed to recover fine-grained concentrate products; therefore, the moisture content in these fine-grained concentrate products is a crucial quality indicator. The hot-pressure filtration and drying dehydration technique can reduce the moisture content in the flotation concentrate slurry to the levels achievable by thermal drying in just one step. Examples of applications include: ⑴ Luoyang Luanchuan molybdenum concentrate, with a concentration of 35%, 60–70% content at -200 mesh, and a grade of 40%. Through this technology, filtration and drying are combined into one process, allowing the moisture content in the flotation molybdenum concentrate to be reduced to below 10% in just one step, with a 100% recovery rate. This approach eliminates the drawbacks of traditional methods such as using large-scale drying systems, which are inefficient, involve harsh operating conditions, and result in significant losses of concentrate due to the use of bag collectors to capture exhaust gases. ⑵The copper and silver ores in Xinjiang have a fine particle size and high mud content. Previously, microporous ceramic disk vacuum filters were used, but these filters would often get clogged, and the high moisture content made it impossible to use them. As a result, precipitation in sedimentation tanks followed by natural drying was the only option for processing. Due to the strong winds and sandstorms in Xinjiang, significant losses occurred on a daily basis. By applying this technology, the moisture content of the copper and silver concentrates can be reduced to below 10% in just one step, with 100% recovery rate, thereby achieving substantial economic benefits. ⒋Sludge dewatering As environmental awareness grows in China, the construction of industrial and domestic wastewater treatment plants is on the rise. Industrial and domestic wastewater is treated to become reclaimed water or clean water that meets regulatory standards before being discharged or reused. However, the resulting sludge treatment issue poses a problem of secondary pollution in reality. Since current mechanical sludge dewatering methods such as centrifuges, belt filter presses, or box filter presses can only reduce the moisture content to between 65% and 80%, applying methods such as thermal drying, incineration, or landfilling faces restrictions related to investment and environmental protection, leaving a significant gap from the goals of reducing sludge volume and utilizing it as a resource. By applying the thermal pressure filtration and drying technology for sludge, the moisture content of industrial sludge can be reduced to below 20% in one step, while that of domestic sludge can be reduced to below 35%. For example, at Ningbo Baoxin Stainless Steel Co., Ltd. under Baosteel Group, industrial sludge was previously processed using two box-type filter presses manufactured by the American company EIMCO; the moisture content in the resulting sludge product was 65%–70%. By switching to a heat-pressure filtration and drying system, the moisture content in the sludge product was reduced to 20% all at once, saving nearly 10 million yuan in waste disposal costs each year.