US 12,331,459 B2
Ragger systems and methods for removing solid debris from pulping processes
Christopher Demler, Lebanon, OH (US); Daniel Parenteau, Montreal (CA); Patrick McEnroe, Cincinnati, OH (US); Michael Lopane, West Chester, OH (US); and Gary Scott Williamson, Middletown, OH (US)
Assigned to KADANT BLACK CLAWSON, LLC, Lebanon, OH (US)
Filed by Kadant Black Clawson LLC, Lebanon, OH (US)
Filed on Feb. 11, 2022, as Appl. No. 17/669,882.
Claims priority of provisional application 63/148,666, filed on Feb. 12, 2021.
Prior Publication US 2022/0259802 A1, Aug. 18, 2022
Int. Cl. D21B 1/32 (2006.01); D21B 1/34 (2006.01); D21C 7/12 (2006.01)
CPC D21B 1/32 (2013.01) [D21B 1/34 (2013.01); D21C 7/12 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A ragger system for removing solid debris from a pulper vessel of a pulping system, the ragger system comprising:
a ragger operable to pull a tail of solid debris from the pulper vessel, the ragger comprising:
a puller mechanism comprising a puller drive operatively coupled to the puller mechanism, the puller mechanism operable to engage the tail and pull the tail from the pulper vessel;
a rider roll spaced apart from the puller mechanism; and
a pressure device configured to adjust a pressure of the rider roll on the tail disposed between the puller mechanism and the rider roll;
at least one measurement device operable to measure one or more input variables indicative of one or more attributes of the tail, one or more operating conditions of the ragger, one or more operating conditions of the pulping system, or combinations thereof, wherein the at least one measurement device comprises a position sensor operable to determine a position of the rider roll relative to the puller mechanism; and
a control system comprising a processor, a memory module communicatively coupled to the processor, and machine readable and executable instructions stored on the memory module, wherein:
the control system is communicatively coupled to the at least one measurement device and to the puller drive, the pressure device, or combinations thereof; and
the machine readable and executable instructions, when executed by the processor, cause the ragger system to automatically:
measure a positon of the rider roll relative to the puller mechanism with the position sensor;
determine a thickness of the tail from the position of the rider roll relative to the puller mechanism as measured by the position sensor; and
adjust the rate of withdrawal of the tail, the direction of the puller drive, the pressure of the pressure device, the torque on the rider roll, the speed of the rider roll, or combinations thereof based on the determination of the thickness of the tail.
 
11. A ragger system for removing solid debris from a pulper vessel of a pulping system, the ragger system comprising:
a ragger operable to pull a tail of solid debris from the pulper vessel, the ragger comprising:
a puller mechanism comprising a puller drive operatively coupled to the puller mechanism, the puller mechanism operable to engage the tail and pull the tail from the pulper vessel;
a rider roll spaced apart from the puller mechanism; and
a pressure device configured to adjust a pressure of the rider roll on the tail disposed between the puller mechanism and the rider roll;
at least one measurement device operable to measure one or more input variables indicative of one or more attributes of the tail, one or more operating conditions of the ragger, one or more operating conditions of the pulping system, or combinations thereof, wherein:
the at least one measurement device comprises one or more cameras positioned within the pulper vessel or positioned above the pulper vessel, the ragger, or both; and
the one or more cameras are positioned to capture images that include at least 50% of the exposed length of the tail, wherein the exposed length of the tail is the length of the tail from the puller mechanism to a point where the tail enters the pulp slurry in the pulping vessel; and
a control system comprising a processor, a memory module communicatively coupled to the processor, and machine readable and executable instructions stored on the memory module, wherein:
the control system is communicatively coupled to the at least one measurement device and to the puller drive, the pressure device, or combinations thereof; and
the machine readable and executable instructions, when executed by the processor, cause the ragger system to automatically:
measure the one or more input variables with the at least one measurement device, wherein the one or more input variables is indicative of one or more attributes of the tail, one or more operating conditions of the ragger, one or more operating conditions of the pulping system, or combinations thereof;
adjust a rate of withdrawal of the tail, a direction of the puller drive, a pressure of the pressure device, or combinations thereof based on the measured one or more input variables;
capture one or more images of the tail with the one or more cameras, wherein the captured images show at least 50% of the exposed length of the tail; and
process the captured images to produce a thickness profile as a function of position along the length of the tail, where the thickness profile comprises the thickness of the tail at each position along the length of the tail.