Continuous fuel supply for a coal gasification reactor

Abstract

A facility for the continuous supply of a coal gasification plant with finely ground fuel material is disclosed. The fuel is first stored in a storage tank and then fed to a lock hopper system, where it is supplied with gas for the coal gasification reaction. The lock hopper system consists of at least two lock hoppers to achieve that the gas is injected quasi-continuously, and the fuel is then passed to a feed tank in which a constant filling level prevails over a given period of time, so that the fuel is conveyed in a constant, smooth and pressurised flow from this feed tank to the burners. The transfer from at least two lock hoppers to a least one feed tank is carried out by pneumatic dense-flow conveying at solid material densities of at least 100 kg/m 3 and a differential pressure of at least 0.5 bar so that it is possible to arrange the facility components at the same geodetic height or different geodetic heights so as to achieve a space saving and flexible plant construction. The invention also relates to a process for the continuous and uniform supply of finely ground fuel to a coal gasification reactor.

1 - 36 . (canceled) 
     
     
         37 . A facility for supplying solid fuel materials to a reactor for the gasification of solid fuel materials, comprising
 a grinding device;   a dust separator;   a storage tank;   at least two lock hoppers;   a connection device for dense-flow conveying;   a feed tank;   a gasification reactor; and   a device for pressure increase which returns conveying gas from the feed tank to the lock hoppers; wherein
 the grinding device is connected to the storage tank by means of connection devices; 
 the dust separator is installed between the grinding device and the storage tank; 
 the storage tank is connected to the lock hoppers via the connection devices which are suited for gravity flow or dense-flow conveying, and 
 the lock hoppers are connected to a feed tank by means of jointly used connection devices which are suited as continuous supply line for dense-flow conveying, and this feed tank is connected to the gasification reactor via further fuel lines. 
   
     
     
         38 . The facility according to  claim 37 , wherein the transfer of the fuel material from lock hoppers to feed tank or tanks is implemented via at least one connection device and at least one unifying element, and the transfer from the unifying element to the feed tank via individual continuous supply lines for dense-flow conveying or via other unifying elements with transferring connection devices. 
     
     
         39 . The facility according to  claim 38 , wherein the facility includes three lock hoppers and a unifying element, wherein each lock hopper is connected to unifying element via a connection device, and the unifying element is connected to feed tank via a further connection device. 
     
     
         40 . The facility according to  claim 38 , wherein the facility includes three lock hoppers and two unifying elements, wherein two lock hoppers are connected to the first unifying element via connection devices, and the first unifying element is connected to the second unifying element via another connection device, and the third lock hopper is directly connected to the second unifying element via a connection device, and the second unifying element is connected to feed tank via a further connection device. 
     
     
         41 . The facility according to  claim 38 , wherein the facility includes four lock hoppers and three unifying elements, wherein two lock hoppers each are connected to one unifying element each via connection devices, these unifying elements being connected to the third unifying element via further connection elements, and the third unifying element being connected to feed tank via a further connection device. 
     
     
         42 . The facility according to  claim 38 , wherein the facility includes six lock hoppers and two unifying elements, wherein three lock hoppers each are connected to one unifying element each via connection devices, these unifying elements being connected to feed tank via separate connection devices. 
     
     
         43 . The facility according to  claim 38 , wherein the facility includes eight lock hoppers and two unifying elements, wherein four lock hoppers each are connected to one unifying element each via connection devices, these unifying elements being connected to feed tank via separate connection devices. 
     
     
         44 . The facility according to  claim 38 , wherein the facility includes eight lock hoppers and three unifying elements, wherein four lock hoppers each are connected to one unifying element each via connection devices, these unifying elements being connected to the third unifying element via further connection devices, and the third unifying element being connected to feed tank via a further connection device. 
     
     
         45 . The facility according to  claim 37 , wherein the lock hoppers are spatially integrated into grinding unit and are loaded from at least one storage tank for finely ground dried fuel material. 
     
     
         46 . The facility according to  claim 37 , wherein the lock hopper system consists of two or more lock hoppers which may be pressurised from outside. 
     
     
         47 . The facility according to  claim 37 , wherein the lock hopper system is connected to a downstream storage tank which supplies the lock hopper system by gravity conveyance with finely ground fuel material. 
     
     
         48 . The facility according to  37 , wherein the gas side of lock hoppers and feed tank is connected by at least one connection line. 
     
     
         49 . The facility according to  claim 37 , wherein one or more gas introduction devices may be installed in any place of the lock hopper system, the dense-flow conveying lines, the gas-sided connection lines or the feed tank, by which it is possible to influence the conveyance or transport of solid material. 
     
     
         50 . The facility according to  claim 49 , wherein at least one of the devices for the introduction of gas is an injector. 
     
     
         51 . The facility according to  claim 37 , wherein devices may be installed in any place of the lock hopper system, the expansion lines, the recycle lines or the excess gas lines by which the gas flow can be separated from solid material or dust. 
     
     
         52 . A process for supplying finely ground fuel materials to a cooled reactor for gasification with oxygen-containing gasifying agents under pressure, wherein:
 the gasifier outlet temperatures are above the slag melting point in the range between 1200 and 2000° C. and the pressure is between 0.3 and 8 MPa; and   the finely ground fuel material is pressurised via a lock hopper system to a pressure level above the gasifier pressure, transferred to at least one feed tank and from there dosed in dense flow via at least one fuel line to one or more gasification burners of one or several gasifiers; wherein
 the conveying gas volume supplied at the discharge of lock hopper is recovered in feed tank and returned to lock hopper by means of a device for pressure increase; and 
 the transfer from at least two lock hoppers to at least one feed tank is carried out by using a pneumatic continuous supply line jointly, simultaneously or successively at solid material densities of at least 100 kg/m 3  and a differential pressure of at least 0.5 bar. 
   
     
     
         53 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the expansion gases from lock hoppers are at least partially used for blanketing the grinding circuit with inert gas. 
     
     
         54 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the dust separator of the grinding unit is also used for dedusting expansion gases from lock hoppers. 
     
     
         55 . The process for supplying finely ground fuel materials according to  claim 52 , wherein pressurising by supplied gas is preceded by a mutual partial pressurisation of lock hoppers. 
     
     
         56 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the fuel material is conveyed from lock hoppers to feed tanks via a number of continuous supply lines which is smaller than the number of lock hoppers. 
     
     
         57 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the solid material from the outlet of each lock hopper is passed to unifying elements via a connection device and then into the continuous supply line, the number of unifying elements being smaller than the number of lock hoppers and at least identical with the number of continuous supply lines. 
     
     
         58 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the unifying elements are provided as closely to and preferably symmetrically to the outlet nozzles of lock hoppers. 
     
     
         59 . The process for supplying finely ground fuel materials according to  claim 52 , wherein temporarily at least two lock hoppers discharge solid material simultaneously into continuous supply line. 
     
     
         60 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the feed tank is spatially integrated into the building of the grinding unit. 
     
     
         61 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the geodetic installation height of lock hoppers is smaller than the installation height of feed tank. 
     
     
         62 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the continuous supply line enters feed tank below the solid material level. 
     
     
         63 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the particle size of the solid fine-grain fuel materials is smaller than 0.5 mm. 
     
     
         64 . The process for supplying finely ground fuel materials according to  claim 52 , wherein continuous supply from lock hoppers is controlled by adjusting the pressure difference between lock hopper and feed tank such that the filling level of feed tank is kept constant. 
     
     
         65 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the gas inlet or outlet into the free space of the lock hoppers influences the pressure difference between lock hopper and feed tank and is used as control parameter for the transport of solid material. 
     
     
         66 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the discharge of solid material is facilitated by the addition of gas into the lock hopper in immediate vicinity to the discharge nozzle. 
     
     
         67 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the density in continuous supply line is adjusted by adding gas into continuous supply line and/or unifying element. 
     
     
         68 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the continuous supply line can be purged by adding gas into continuous supply line itself and/or into unifying element. 
     
     
         69 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the connection elements between lock hopper and unifying element are supplied with gas. 
     
     
         70 . The process for supplying finely ground fuel materials according to  claim 52 , wherein the conveying gas volume supplied at the discharge of lock hopper is recovered in feed tank and returned to lock hopper by means of an injector. 
     
     
         71 . The process for supplying finely ground fuel materials according to  claim 69 , wherein the propellant gas which serves to control the pressure of lock hopper is used to operate injector.