China's Low-Grade Coal Pyrolysis Technology Has Made A Major Breakthrough 22 Aug 2018
Li Shousheng, president of the China Petrochemical Federation, said that Shaanxi's development of coal chemical industry has obvious advantages and distinctive features, not only rich in resources, but also strong in technological innovation. This technology has opened up a new process route for China's modern coal chemical industry. On this basis, it must continue to innovate, realize the cross-border development of industrial coupling through the use of coal pyrolysis and its product quality.
The technology focuses on the hybrid coal pyrolysis with different particle sizes below 30mm. It is divided into multi-layer processing, uniform heat and mass transfer, high-efficiency separation of oil dust, self-produced hydrogen-rich gas circulation heat carrier regenerative heating, medium-low temperature grading coupling. The key technologies such as pyrolysis and dry quenching are integrated. The successfully developed segmented multi-layer vertical pyrolysis furnace has a processing capacity of 500,000 tons/year, and has a multi-layer structure inside, using drying, dry distillation and cooling. The method of segmentation treatment realizes self-dusting and uniform cloth distribution in the furnace, which effectively solves many technical problems such as industrialization of mixed coal pyrolysis, small scale of single treatment, and low efficiency of oil-dust separation.
The main innovation of this technology lies in the use of mixed coal into the multi-stage pyrolysis, the raw material cost is low; precise temperature control, product quality is adjustable; low-temperature grading coupling pyrolysis, high tar yield and light component content; Flexible control of pyrolysis temperature, reducing heat carrier circulation and reducing equipment investment; good gas quality, can be used as raw material for hydrogen production or processing of LNG.
It is understood that China's low-grade coal is rich in resources and widely distributed. It has the characteristics of high volatile matter, low ash content and good chemical reactivity. It is very suitable for comprehensive utilization of this technology, and has broad application prospects, economic benefits and significant social importance. If the local conversion of 1 billion tons of low-grade coal is carried out in the western region, it is roughly estimated that it can produce 650 million tons of semi-coke, 80 million tons of tar and 160 billion cubic meters of gas per year.
At present, the first phase of the 30 million tons/year coal quality clean and efficient conversion multi-generation project planned by Shaanxi Coal Group in Yulin has been started. Pyrolysis is the first process of the project. coal pyrolysis technology will be the main support.