Coal slime dryer has always have the disadvantages of big noise, uneven feeding, large volume, heavy and so on, and even the smallest coal slime dryer has 7.5 t. In facing so large and clumsy coal slime dryer, we should find method to save time, labor and reduce operation failures, then the intelligent of coal slime dryer is one of the best methods to reduce failure. On the one hand, intelligent can reduce labor cost, remote monitor the operation situation at any time, and at maximun reduce failure rate. And on the other hand, the intelligent of coal slime dryer can immediately check the failures, and reduce wastes and accidents.Three return the dryer actually is a kind of the three-cylinder dryer, and it is the upgrade product of three cylinders dryer. From the point of appearance, three return type dryer at one side is conical, and the other side is round, while three-cylinder dryer both the two ends are round. From the working principle to analyze, the cylinder is divided into internal cylinder, middle tube and outer cylinder, the working principle of three return dryer is same with the three-cylinder dryer. From the working efficiency of dryers, three return dryer is suitable for drying small amount of materials, and drying effect is better. While three-cylinder dryer is suitable for drying large amount of materials, and the drying effect is lower than three return dryer. From the covering area, three return dryer is smaller than three-cylinder dryer. Henan Hongxing is the domestic famous dryer manufacturer, has been actively preparing for the better development of dryer. Hongxing sand dryer has the advantages of easy and convenient parameter-setting, simple transmission system, reliable operation, convenient maintenance, which provides broad market space for sand dryer. The control of sand dryer is completed by software, which is convenient for function adjustment and technology upgrade. Great support of science and technology, and adds the constant…