Waste Paper and Pulpers
The waste paper bales or pulp bales are fed in via a conveyor to the pulper and repulped by adding process water. The pulper rotator (agitator) ensures the disintegration of waste paper fibers. Some systems process only one batch at a time, while others operate continuously, such as repulping drums used for waste paper.
Conveyor Detection with the VEGASON 62
The VEGASON 62 ultrasonic sensor detects if the paper loading height on the conveyor belt is exceeded, as well as any possible blockages thus ensuring reliable automation of the process.
Level Measurement with the VEGABAR 64
Accurate level measurement inside a pulper ensures the correct proportion of waste paper, or pulp, to process water. The VEGABAR 64 pressure transmitter with rugged CERTEC® measuring cell is used for this measurement. The instrument is always mounted on a socket inclined in rotation direction and equipped with a rinsing facility.
Level Measurement with the VEGABAR 65
The VEGABAR 65 with metallic METEC® measuring cell is implemented for level measurement in pulpers for filter and teabag paper with low pH value.
Efficient Fiber Separation in the Pressurized Screen
Any impurities bigger than the fibers must be separated out. For this purpose, the fiber suspension is pumped through a pressurized screen at a pressure of approximately 29 psig (2 bar) at approximately 122°F (50°C). The material flows in tangentially along the surface of rotating screen cylinders with holes or slots. The screening machines have an inlet, an outlet for good material (accept) and an overflow for sorted out material (reject). The separating efficiency is defined by the hydraulic pressure of the screen, the dimensions of the holes or slots and the quantity of reject.
Pressure Measurement with the VEGABAR 54 and VEGABAR 64
For effective screening, the machine must be run with the correct operating parameters. For this purpose, the pressure is measured at the inlet and discharge areas. For this measurement the VEGABAR 64 pressure transmitter with ceramic CERTEC® measuring cell and process connection M44x1.25 is used. As an alternative, the VEGABAR 54 with the small ceramic CERTEC® measuring cell and process connection M30x1.5 is also available.
Further typical applications for the VEGABAR 54 or VEGABAR 64 are level and pressure measurement on the cleaners, in the flotation tank and on the disc filters.
Storage Towers and Chests
For continuous operation, large quantities of the prepared stock are necessary. The material is held in storage towers with capacities up to 2000 m3 volume and up to 98 ft (30 m) height. Also product from the pulper is stored in similar towers and chests. Large throughput and internal stirrers ensure a homogeneous substance.
Level Measurement with the VEGAPULS 66
The level measurement must deliver reliable information on the contents of the towers. A VEGAPULS 66 radar sensor with a DN 250 flange and large horn antenna is best suited for the measurement in the upper part of the towers. Unaffected by the difficult measuring conditions in the towers, the sensor delivers absolutely reliable measurement data. Compact bridges inside the tower prevent measurement all the way to the bottom of the vessel. For that reason, a separate sensor is implemented for the required level measurement in the lower area of the tower.
Level Measurement with the VEGABAR 54
The material is made pumpable by mixing in process water with an agitator. The additional level measurement in the lower range detects the substance suspension and prevents the stirrer from running dry. For this application the pressure transmitter VEGABAR 54 with the ceramic CERTEC® measuring cell in combination with a ball valve fitting is used.
