The invention pertains to a process for modifying gypsum, wherein a continuous feed of raw gypsum is provided; the water content of the raw gypsum is determined in the continuous feed by near infrared spectroscopy (NIR) measurement; the raw gypsum is calcined in a calcination unit at a fire rate to remove water from the raw gypsum and to obtain a continuous feed of calcined gypsum having a water content within a selected range; a water content of the calcined gypsum is determined by near infrared spectroscopy, and the fire rate is adjusted based on the water content of the raw gypsum and of the calcined gypsum. Further, the invention pertains to an apparatus for performing said process.

The invention pertains to a process for modifying gypsum, wherein a continuous feed of raw gypsum is provided; the water content of the raw gypsum is determined in the continuous feed by near infrared spectroscopy (NIR) measurement; the raw gypsum is calcined in a calcination unit at a fire rate to remove water from the raw gypsum and to obtain a continuous feed of calcined gypsum having a water content within a selected range; a water content of the calcined gypsum is determined by near infrared spectroscopy, and the fire rate is adjusted based on the water content of the raw gypsum and of the calcined gypsum.

Further, the invention pertains to an apparatus for performing said process.

The present invention provides a device for smelting and regenerating phosphogypsum using high-temperature ceramsite and method for using same, where a rotary kiln is used to accept high-temperature ceramic granules that have been calcined and formed. The residual heat of the high-temperature ceramic granules allows them to be fully mixed with the phosphogypsum. On one hand, the high temperature of the ceramic granules achieves high-temperature dehydration of the phosphogypsum. On the other hand, the porous adsorption property of the ceramic granules can facilitate full absorption of some harmful substances in the phosphogypsum, thereby realizing the purification of the phosphogypsum. In addition, because the dehydrated phosphogypsum is generally in a suspended state, the rotary kiln of the present invention is equipped with a discharge outlet at the end. The discharge outlet uses a combination of a cyclone dust aspirator and a baghouse dust collector, which can draw out the phosphogypsum that has been fully dehydrated and is suspended in the rotary kiln, thereby realizing its complete collection without any leakage and achieving zero pollution.