System and method for rapid pyrolysis of coal

Abstract

The present invention provides a system and a method for rapid pyrolysis of coal. The system comprises: a rapid pyrolysis reactor, which comprises: a reactor body defining a reaction space that forms a dispersion region, a pyrolysis region, and a discharge region from top to bottom; said dispersion region comprises: a material distributor; a coal inlet arranged above the material distributor; a material distribution gas inlet connected to the material distributor; said pyrolysis region comprises: multilayer regenerative radiant tubes, which are distributed at an interval in the height direction of the reactor body in the pyrolysis region, and each layer of regenerative radiant tubes consists of a plurality of regenerative radiant tubes distributed at an interval in the horizontal direction; said discharge region comprises: a semi-coke outlet; a plurality of pyrolysis gas outlets, which are arranged in the dispersion region and/or the pyrolysis region respectively; a slag cooler connected to the semi-coke outlet, and a cooling device connected to the pyrolysis gas outlet.

1 . A system for fast pyrolysis of coal, comprising:
 a fast pyrolysis reactor,   said fast pyrolysis reactor comprises:   a reactor body defining a reaction space that forms a dispersion region, a pyrolysis region, and a discharge region from top to bottom;   said dispersion region comprises:   a material distributor;   a coal inlet arranged above the material distributor;   a material distribution gas inlet, which communicates with the material distributor so as to utilize a material distribution gas to blow out the coal in the material distributor into the dispersion region, so that the coal falls into the pyrolysis region uniformly;   said pyrolysis region comprises:   multilayer regenerative radiant tubes, which are distributed at an interval in the height direction of the reactor body in the pyrolysis region, and each layer of regenerative radiant tubes consists of a plurality of regenerative radiant tubes distributed at an interval in the horizontal direction;   said discharge region comprises: a semi-coke outlet;   a plurality of pyrolysis gas outlets, which are arranged in the dispersion region and/or the pyrolysis region respectively;   the fast pyrolysis reactor is adapted to treat the coal by fast pyrolysis with the regenerative radiant tubes, so as to obtain semi-coke and pyrolysis gas;   a slag cooler connected to the semi-coke outlet and adapted to cool the semi-coke; and   a cooling device connected to the pyrolysis gas outlet and adapted to cool the pyrolysis gas, so as to obtain tar and fuel gas.   
     
     
         2 . The system according to  claim 1 , wherein further comprising:
 a coal bunker adapted to store coal;   a drying and upgrading tube connected to the coal bunker and the fast pyrolysis reactor respectively and adapted to dry and upgrade the coal with hot flue gas before the coal is controlled to have a fast pyrolysis reaction; and   a first blower fan connected to the regenerative radiant tubes and the drying and upgrading tube respectively and adapted to supply high-temperature flue gas generated in the regenerative radiant tubes as hot flue gas to the drying and upgrading tube.   
     
     
         3 . The system according to  claim 1 , wherein the cooling device is a spraying tower, in which the pyrolysis gas is sprayed with a cooling liquid so as to cool the pyrolysis gas. 
     
     
         4 . The system according to  claim 3 , wherein further comprising:
 a tar trough connected to the spraying tower and adapted to treat the tar by settlement so as to obtain tar in an upper layer and tar in a lower layer;   an oil pump connected to the tar trough and the spraying tower respectively and adapted to supply the tar in the upper layer as the cooling liquid to the spraying tower;   a tar storage tank connected to the tar trough and adapted to store the tar in the lower layer.   
     
     
         5 . The system according to  claim 3 , wherein further comprising:
 a water seal device connected to the spraying tower.   
     
     
         6 . The system according to  claim 3 , wherein further comprising:
 a fuel gas storage tank connected to the spraying tower and adapted to store the fuel gas;   a second blower fan connected to the fuel gas storage tank and the regenerative radiant tubes respectively and adapted to supply one part of the fuel gas to the regenerative radiant tubes; and   a third blower fan connected to the fuel gas storage tank and the material distribution gas inlet respectively and adapted to supply the other part of the fuel gas as material distribution gas to the material distribution gas inlet.   
     
     
         7 . The system according to  claim 1 , wherein each layer of regenerative radiant tubes consists of a plurality of regenerative radiant tubes that are parallel to each other and evenly distributed, and each regenerative radiant tube is parallel to each regenerative radiant tube in adjacent upper and lower layers of regenerative radiant tubes and is staggered from each regenerative radiant tube in adjacent upper and lower layers of regenerative radiant tubes in the height direction of the reactor body. 
     
     
         8 . The system according to  claim 1 , wherein the reactor body is in 2-20 m height. 
     
     
         9 . The system according to  claim 1 , wherein the regenerative radiant tubes are in 100-500 mm diameter. 
     
     
         10 . The system according to  claim 1 , wherein, the horizontal spacing and vertical spacing between the outer walls of adjacent regenerative radiant tubes are 100-500 mm respectively and independently. 
     
     
         11 . The system according to  claim 1 , wherein a fuel gas regulating valve is provided on the regenerative radiant tubes. 
     
     
         12 . A method for fast pyrolysis of coal with the system for fast pyrolysis of coal according to  claim 1 , comprising:
 supplying a material distribution gas via the material distribution gas inlet to the material distributor, supplying coal via the coal inlet to the reaction space, supplying a combustible gas and air into the regenerative radiant tubes, so that the combustible gas is combusted in the regenerative radiant tubes and generate heat to carry out fast pyrolysis of the coal, so as to obtain pyrolysis gas and semi-coke;   supplying the semi-coke via the semi-coke outlet to the slag cooler, so as to cool the semi-coke; and   cooling the pyrolysis gas discharged via the pyrolysis gas outlets in a cooling device, so as to obtain tar and fuel gas.   
     
     
         13 . The method according to  claim 12 , wherein the temperature difference in a single regenerative radiant tube is no more than 30° C. 
     
     
         14 . The method according to  claim 13 , wherein the pyrolysis region forms a preheating section, a fast pyrolysis section, and a complete pyrolysis section from top to bottom. 
     
     
         15 . The method according to  claim 14 , wherein the temperature in the regenerative radiant tubes in the preheating section is 550-900° C., the temperature in the regenerative radiant tubes in the fast pyrolysis section is 500-800° C., and the temperature in the regenerative radiant tubes in the complete pyrolysis section is 500-800° C. 
     
     
         16 . The method according to  claim 12 , wherein further comprising:
 drying and upgrading the coal with a hot flue gas in the drying and upgrading tube before the coal is supplied to the reaction space; and   supplying the high-temperature flue gas produced in the regenerative radiant tubes to the drying and upgrading tube by means of the first blower fan.   
     
     
         17 . The method according to  claim 12 , wherein the cooling device is a spraying tower, in which the pyrolysis gas is sprayed with a cooling liquid so as to cool the pyrolysis gas. 
     
     
         18 . The method according to  claim 12 , wherein further comprising:
 storing the fuel gas in the fuel gas storage tank;   supplying one part of the fuel gas as fuel to the regenerative radiant tubes by means of the second blower fan; and   supplying the other part of the fuel gas as material distribution gas to the material distribution gas inlet by means of the third blower fan.   
     
     
         19 . The method according to  claim 12 , wherein the fast pyrolysis time is 2-30 s. 
     
     
         20 . The method according to  claim 12 , wherein the particle size of the coal is smaller than 3 mm.