The present disclosure relates to the technical field of phosphogypsum dehydration treatment, and provides a device for harmless treatment of phosphogypsum by calcination using high-temperature ceramsite, including a rotary kiln, a first feeding unit, a second feeding unit and a sorting assembly, where the rotary kiln includes a first rotary kiln drum and a second rotary kiln drum; a first interlayer channel is formed between the first rotary kiln drum and the second rotary kiln drum, and a head end of the first interlayer channel is connected to a head end of the first rotary kiln drum; the first feeding unit is used to input high-temperature ceramsite into the first rotary kiln drum; the second feeding unit is used to input phosphogypsum into the first interlayer channel; the mixture in the first rotary kiln drum and the phosphogypsum in the first interlayer channel can exchange heat to dehydrate the phosphogypsum; the sorting assembly is used to sort the mixture output from the first rotary kiln drum to obtain calcined phosphogypsum. The present disclosure enables high calcination and dehydration efficiency of phosphogypsum, and can achieve low-carbon harmless treatment of phosphogypsum to obtain phosphorus building gypsum.

An installation for thermal treatment of free-floating raw material, in particular cement raw meal and/or mineral products, may include a riser line through which hot gases can flow. The riser line has at least one fuel inlet for introducing fuel into the riser line. The riser line has at least one raw meal inlet for introducing raw meal into the riser line, which raw meal inlet is arranged upstream of the fuel inlet in a flow direction of gas inside the riser line. Further, a method for thermal treatment of free-floating raw material may involve introducing fuel via a fuel inlet into a riser line for guiding hot gases and introducing raw meal into the riser line. The raw meal is introduced into the riser line upstream of the fuel inlet in the flow direction.

A hydrogen-plasma rotary kiln furnace reactor and a method of reducing iron ore to iron using the same are disclosed. The hydrogen-plasma rotary kiln furnace includes a rotary kiln furnace and a hydrogen-plasma generator.