Method for pulp quality control and regulation

Claim 1

A method for control of the consistency of a slurry or pulp fluid material proceeding from a sedimentation zone or thickener tank, comprising establishing a reference displacement time for a known volume of said fluid moving under a constant force or head load through a known distance, the displacement time being representative of a desired average state of consistency of said fluid volume, thereafter passing a known volume of said fluid under a constant head through said known distance, measuring the an actual displacement time of said volume of fluid consumed in moving through said known distance, calculating the difference between said reference displacement time and the measured actual displacement time, and adjusting the volume of moving fluid or the prior physical conditioning or elaboration of said fluid material to maintain or restore the desired average state of consistency.

Claim 2

A method for control of the consistency of a slurry or pulp fluid material proceeding from a sedimentation zone or thickener tank, comprising establishing a reference displacement time for a known volume of said fluid moving under a constant force or head load through a known distance, the displacement time being representative of a desired average state of consistency of said fluid volume, thereafter passing a known volume of said fluid under a constant head through said known distance, measuring the an actual displacement time of said volume of fluid consumed in moving through said known distance, calculating the difference between said reference displacement time and the measured actual displacement time, and adjusting the volume of moving fluid or the prior physical conditioning or elaboration of said fluid material to maintain or restore the desired average state of consistency.

Claim 6

A method for control of the consistency of a slurry or pulp fluid material proceeding from a sedimentation zone or thickener through a pipe line to a place of utilization or further treatment in an intermittently pulsed flow imparted by a reciprocating positive displacement volumetric pump in the pipe line having constant intake and discharge strokes and operating under a constant delivery head load, comprising operating the pump with a preset pumping cycle frequency to provide a predetermined output flow rate, determining a reference discharge time for the pump representative of a desired average state of fluid consistency, measuring an actual discharge time for the pump on each discharge stroke, comparing the measured actual discharge time with the reference discharge time to determine the corresponding time difference and adjusting the pumping cycle frequency governing the flow rate in the pipe line, or selectively varying the physical state in the sedimentation zone or thickener to alter the consistency of said fluid, until said time difference has been reduced sufficiently to restore the actual discharge time to correspondence with the reference discharge time and thereby reestablish the average state of fluid consistency in the pipe line.

Claim 7

A method for control of the consistency of a slurry or pulp fluid material proceeding from a sedimentation zone or thickener through a pipe line to a place of utilization or further treatment in an intermittently pulsed flow imparted by a reciprocating positive displacement volumetric pump in the pipe line having constant intake and discharge strokes and operating under a constant delivery head load, comprising operating the pump with a preset pumping cycle frequency to provide a predetermined output flow rate, determining a reference discharge time for the pump representative of a desired average state of fluid consistency, measuring an actual discharge time for the pump on each discharge stroke, comparing the measured actual discharge time with the reference discharge time to determine the corresponding time difference and adjusting the pumping cycle frequency governing the flow rate in the pipe line, or selectively varying the physical state in the sedimentation zone or thickener to alter the consistency of said fluid, until said time difference has been reduced sufficiently to restore the actual discharge time to correspondence with the reference discharge time and thereby reestablish the average state of fluid consistency in the pipe line.