Paper manufacturing is a demanding process that relies on consistency, precision and control at every stage. From the preparation of raw pulp to the continuous operation of bleaching towers and storage systems, each phase presents unique measurement challenges. In South Africa, where local mills must remain competitive in a global industry, reliable instrumentation is vital to ensuring operational efficiency and maintaining product quality.
Where the pressure is on
During stock preparation, pressure screens are tasked with removing contaminants and filtering out usable fibres. Operating under conditions of constant pressure changes, abrasive materials, and flow variability, these units require accurate pressure monitoring. The VEGABAR 82 pressure transmitter is well-suited to these harsh environments. With a robust ceramic measuring cell, it delivers stable readings even in the presence of pressure surges and solid-laden media. Maintaining the correct pressure differential across the screen is critical, and continuous monitoring helps ensure that only clean, well-prepared stock moves forward in the process.
From brown to brilliant
The bleaching stage involves the use of strong oxidising agents such as oxygen, ozone or hydrogen peroxide to remove lignin and whiten the pulp. These chemicals are introduced into 25 meter-high towers that operate continuously at temperatures close to 95°C. Given their size and operational demands, these towers are never emptied and require ongoing level monitoring.
Here, a combination of VEGAPULS 6X, VEGABAR 82 and VEGACAP 64 instruments provides reliable measurement data. VEGAPULS 6X, with its radar-based, non-contact level sensing, handles high temperatures and steam-laden environments without loss of accuracy. The VEGACAP 64, a capacitive level switch, adds redundancy and ensures safe, reliable operation under variable conditions. Together, these instruments allow process engineers to maintain chemical dosing and pulp consistency at optimal levels, avoiding overflows, dry runs or chemical waste.
No blockages allowed
At the start of the process, waste paper or pulp bales are introduced into the pulper via conveyor belts. Here, they’re combined with process water and broken down by mechanical stirrers. The aggressive motion of the stirrers, coupled with possible foreign objects like wires or metal debris, creates a demanding measuring environment.
Bales, belts and breakdowns? Not with VEGAMIP 61 and VEGABAR 82 on duty. For these conditions, VEGAMIP 61, a microwave-based sensor, provides non-intrusive level detection, even through thick vessel walls or turbulent product surfaces. Used alongside the VEGABAR 82, this setup allows for accurate detection of water-to-fibre ratios, essential for maintaining fibre consistency. Additionally, conveyor monitoring with VEGAMIP ensures that blockages or jams from bale congestion are quickly identified and addressed before they cause downtime.
Stocked and steady
Once prepared, the stock is stored in large vertical towers with high throughput. Constant agitation within these towers ensures homogeneity but also creates turbulent surfaces, foam and steam, all of which can interfere with less capable sensors.
With agitators churning and steam rising, storage towers are chaos without the calm of good level measurement. VEGAPULS 6X proves its value here. Designed for difficult conditions, it provides accurate, continuous level readings regardless of condensation or agitation. Paired with VEGABAR 82, which can handle temperature fluctuations and mechanical stress, this setup helps avoid dry running of agitators, ensures consistent material availability and prevents unplanned stoppages in the production line.
Zero drift, maximum uptime
IO-Link, myVEGA and non-contact radar keep calibration and diagnostics friction-free. VEGA’s instruments are designed to integrate easily with industrial control systems, offering IO-Link capabilities, wireless adjustment via Bluetooth and compatibility with myVEGA for streamlined configuration and monitoring. This connectivity supports more agile operations, where maintenance teams and operators can make adjustments in real time or access diagnostics without stopping the process.
The hidden heroes of paper
Reliable measurement and monitoring at every stage of the paper manufacturing process are essential, not just for maintaining output, but also for achieving long-term sustainability and competitiveness. With instrumentation like VEGAPULS 6X, VEGABAR 82, VEGACAP 64, VEGAMIP 61 and others, South African mills are better equipped to meet the demands of both local and global markets. These tools support better decision making, reduce production risks and enable smarter, more resilient operations from pulp to finished product.
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