Patent GB-855086-A (GB)
Title: Process and apparatus for pelleting carbon black
IPC: C09C1/60
Filed: 1958-07-10
Abstract: <PICT:0855086/III/1> Carbon black recovered from carbon black furnaces by recovery equipment comprising cyclone separators and bag filters is suspended in a gaseous stream and transported thereby to a common feed line and thence to a plurality of individual, parallel connected, feeder cyclones, each of which is connected via an individual feeder conveyer to a separate pelleting mill, the feeder conveyer being also connected to a common pick-up line for recycle of unpelleted black to the common feed line when the mill associated therewith is shut down, the carbon black recovered from each feeder cyclone being passed to the mill associated therewith and the resultant pelleted black removed from each mill.  The gaseous suspension is formed preferably in a gaseous stream derived from the carbon black furnaces or recovery equipment and the recycle of unpelleted black from the feeder conveyer to the common feed line is preferably effected by transporting the black in gaseous suspension in the effluent gases from the feeder cyclones through the common pick-up line to the recovery equipment which completes the cycle by delivering such recycled black together with fresh black to the common feed line.  Gaseous effluent containing suspended carbon black from furnace 10 is quenched in line 18 by water injected at 20 and, after passing through secondary water quench 22, is passed through a series of cycles 29 and 30 and thence to bag filter 34, clean effluent gases being vented through 36.  Hot carbon black from cyclones 29 and 30 is passed by conveyer 40 to micro-pulveriser 42 and thence to feed line 46, where it is augmented with carbon black from bag filter 34 entering through lines 45.  Carbon black is conveyed in line 46 as a gaseous suspension in the effluent gas from cyclone 30, entering 46 through line 33, to line 54 and thence to common feed line 56 which is connected to individual cyclone separators 61, 62, 63 and 64.  The cyclones are connected to pelleting mills 66, 67, 68 and 69 by conveyers 71, 72, 73 and 74 respectively. Effluent gases from the cyclones are passed to pick-up line 80 which connects to recycle line 81 which in turn connects to line 46 either directly through 82 and/or through line 28, primary cyclones 29 and 30 and line 47 and are used for maintaining a gaseous suspension of black in these lines.  In order to permit continuous operation of the cyclone separator when the corresponding pellet mill is shut down recycle of black directly into pick-up line 80 is afforded by means of lines 85, 86, 87 and 88 each containing a star valve 90 operated in conjunction with motor 92 whereby the valve is opened when the motor is shut down. Pelleted black produced in the mills is removed by lines 96 to a product conveyer 98 which delivers to storage or transport. Concentration of carbon in the recycle line 81 is determined by means of BETA or g  radiation directed from source 100 through the suspension in 81 on to absorption gauze 102 which records on meter 104, the overall rate of pelleting being regulated in response to this concentration.