Method and system for producing pellets from biomass in a pellet press for use as fuel in fireplaces

Abstract

A system and a method for producing pellets from biomass in a pellet press for use as fuel in fireplaces. To produce pellets in an energy-saving and more energetically cost-effective manner as compared to prior art. In the method according to one embodiment, the biomass, which comprises cellulosic and/or lignocellulosic fibers, chips or shreds and is heated and dried in the course of the production process in a dryer, separated from the dryer air, and the biomass is supplied to a pellet press, wherein the temperature of the biomass is heated or substantially maintained by hot air in a treatment region between the dryer and the pellet press, and the treatment region comprises at least parts of the transport path and/or at least one additional device for carrying out at least one additional method stop, and wherein the temperature of the hot air exceeds at least 65° Celsius.

1 . A method for producing pellets from biomass in a pelletizing press for use as a fuel in fireplaces, the biomass comprising fibers, chips, or shreds, which contain cellulose and/or lignocellulose, the biomass being heated and dried in the course of the production in a dryer, the dried and heated biomass being separated from the dryer air, and the biomass being supplied to a pelletizing press,
 wherein the temperature of the biomass is heated or essentially maintained using hot air in a treatment area between the dryer and the pelletizing press, and the treatment area comprises at least parts of the transport path and/or at least one further device for performing at least one additional method step, and the temperature of the hot air exceeds at least 65° C.   
     
     
         2 . The method according to  claim 1 , wherein the temperature of the hot air is set using a heating device, the heating device using fresh air as the supply air and/or preheated air from at least one hot-air return line and/or preheated air from a heat exchanger of the waste heat of a pellet cooler after the pelletizing press. 
     
     
         3 . The method according to  claim 1 , wherein, in the treatment area, the at least one device for performing at least one further method step comprises a heavy material separator for separating heavy material and/or a grinding device for chopping the biomass and/or a cyclone for separating the hot air from the biomass. 
     
     
         4 . The method according to  claim 1 , wherein at least one device for performing at least one further method step and the heating device guide the hot air in the treatment area in an essentially closed loop. 
     
     
         5 . The method according to  claim 4 , wherein the hot air in the circuit of the treatment area is regularly replaced and/or filtered at least in parts. 
     
     
         6 . The method according to  claim 1 , wherein the temperature of the hot air is set in such a manner that the biomass reaches the pelletizing press at a temperature of greater than 65° C. 
     
     
         7 . The method according to  claim 1 , wherein the dryer is a drum dryer, and the biomass leaves the drum dryer at a temperature of substantially greater than 65° C. 
     
     
         8 . The method according to  claim 1 , wherein the biomass, in a further method step, is transported by means of hot air through at least one heavy material separator and/or guided through a grinding device and chopped. 
     
     
         9 . The method according to  claim 1 , wherein the biomass, in a further method step, is transported and heated by means of hot air, in particular hot air of a temperature of 70° to 80° C., through at least one heavy material separator and/or guided through a grinding device, chopped, and heated. 
     
     
         10 . The method according to  claim 8 , wherein the biomass, in a further method step, has hot air applied thereto, in particular hot air at a temperature greater than 65° C., in at least one silo and/or in a discharge device associated with the silo. 
     
     
         11 . The method according to  claim 8 , wherein the biomass, in a further method step after the grinding device and/or a heavy material separator, is separated from the hot air in a cyclone, insufficiently chopped parts of the biomass being returned to the grinding device and/or the separated hot air being supplied via a hot-air return line to the heating device. 
     
     
         12 . The method according to  claim 1 , wherein the biomass is at least partially approximately held at the same temperature level or heated, by means of hot air and/or sufficient insulation in relation to the ambient temperature, during the transport and/or the storage between the individual processing steps. 
     
     
         13 . The method according to  claim 11 , wherein the hot air for the transport means, the heavy material separator, the grinding device, a silo, and/or the cyclone is heated at least to the temperature of the biomass. 
     
     
         14 . The method according to  claim 1 , wherein water is supplied to the biomass, in particular sprayed on, essentially shortly before the pelletizing press. 
     
     
         15 . The method according to  claim 14 , wherein the water is heated to a temperature of greater than 65° C., preferably greater than 80° C., particularly preferably 90° C. before or during the supply to the biomass. 
     
     
         16 . The method according to  claim 14 , wherein the water is heated with the biomass after the application to the biomass by means of radiant energy. 
     
     
         17 . A facility for producing pallets from biomass in a pelletizing press for use as a fuel in fireplaces, the biomass comprising fibers, chips, or shreds, which contain cellulose and/or lignocellulose, a dryer having an airlock for separating the drier air being arranged before the pelletizing press in the production direction for drying and heating the biomass, wherein, in the facility, at least one treatment area is arranged between the airlock and the pelletizing press and at least one transport means for transporting the biomass between the dryer and the pelletizing press and/or at least one device for performing at least one further method step is arranged in this treatment area, at least one heating device for heating and/or providing hot air of substantially greater than 65° C. is arranged associated with the treatment area, the heating device being operationally linked at least once with the transport means and/or with a device for performing further method steps to supply the hot air. 
     
     
         18 . The facility according to  claim 17 , wherein, in the facility, insulation elements in relation to the ambient temperature are arranged at least in parts on the transport devices and/or on at least one silo and/or on at least one of the devices for the method steps. 
     
     
         19 . The facility according to  claim 17 , wherein a heavy material separator for separating heavy material and/or a grinding device for chopping the biomass and/or a silo and/or a screen and/or a cyclone for separating the hot-air from the biomass are arranged in the treatment area as the devices for performing at least one further method step. 
     
     
         20 . The facility according to  claim 17 , wherein a silo having an associated discharge device is arranged for storing the biomass. 
     
     
         21 . The facility according to  claim 17 , wherein a hot-air return line is arranged to establish a closed circuit of the hot air in the treatment area. 
     
     
         22 . The facility according to  claim 17 , wherein a pellet cooler, which is arranged with the heating device and/or a heat exchanger for reuse of waste heat, is arranged to store and cool the produced pallets. 
     
     
         23 . The facility according to  claim 17 , used to perform the method according to  claim 1 .