PMCE are the preferred supplier of continuous particulate emission monitors to a number of the worlds leading Gypsum and Plasterboard manufacturers. Worldwide involvement with the industry over many years has led to the development of an unparalleled range of unique solutions for in-stack particulate monitoring, and familiarity with the emission monitoring challenges specific to the Gypsum industries, including:
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Humid flue gases, particularly after calciner and kettle plant and sometimes after the kiln, can result in sticky particulate which can coat the optical surfaces of Opacity instruments and ‘blind’ traditional triboelectric type instruments leading to erroneous signals and data, necessitating frequent instrument maintenance and dependence on fail-safe air purging systems.
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Bagfilter performance monitoring is of particular importance, as the high level of humidity in gypsum plant flue gases can lead to premature deterioration of bagfilter media, and filtration blinding by caking with the sticky particulate matter. The resulting requirement for process interventions and the associated costs therefore highlight the benefits of the ability to predicatively monitor bag filter performance.
PMCE offer approved (TUV & MCERTS) systems for particulate measurement, filter leak monitoring and filter performance monitoring, depending on the plant specific requirements which are specified in close consultation between plant operators and PCME. Gypsum and Plasterboard plant typically demand monitoring on multiple emission points including milling, calcining, kiln, materials transfer, scoring and chamfering plant, which can be addressed with a networked multichannel system. By offering a range of measurement technologies in reliable and rugged instruments, PCME are able to offer a full range of sensor solutions to meet and often exceed legislative compliance, and significantly improve the operation of filter plant including a reduction in filter maintenance requirements.
Quarrying
Processes such as the crushing and drying of gypsum ore to land plaster utilise both bag filters and cyclone filters to collect the product and abate fugitive emissions to air. As the gas streams at this point in the process are typically humid with sticky particulates, traditional monitoring technologies can quickly become ‘blinded’ by coating and require extensive and regular maintenance to ensure continued operation. Similarly after cyclone collectors, rotary dryers and heated roller mills traditional monitoring technologies suffer from signal interference due to the moisture content of the flue gas. By employing patented PCME technology proven to overcome concerns of sensor contamination, process operators can have confidence in more accurate emissions data and therefore greater ability to implement process efficiency improvements.
Impact Mills
Heated impact mills are an alternative to the separate drying, grinding and calcining processes in gypsum plant. The flue gases from product cyclones after the heated impact mill process are similar to those after separate drying plant, therefore the particulate monitoring concerns can be addressed with the same proven technologies.
Calciners & Kilns
Kettle calciner, rotary kiln and flash calciner emissions may be controlled by a number of different abatement plant types. Where electrostatic precipitators are in use, scattered light or transmisometry type particulate monitoring instruments must be used due to the interference experienced by probe electrification type instruments. Increasingly bagfilter plant is more common and as emissions are typically below 200°C, bagfilters are reliably applied without the associated problems of reduced bagfilter service life resulting from high thermal stress operation. However the high level humidity of emissions from the calciner can result in rapid caking of the bagfilter elements, where accurate bagfilter performance data reduces the need for process interventions and extends bagfilter element service life.
Silo Filters
Silo Filters can be remotely monitored with either single sensor units or multi-channel networked systems. These devices log data on-board to assist with accurate setting of alarm levels to facilitate warnings of silo filter leakage or rupture, and the prevention of nuisance emissions.
Processing and Bagging
Several Gypsum and Plasterboard processes such as scoring, chamfering and cutting plant, along with conveying and materials transfer operations produce significant fugitive emissions which can be controlled with process filters and often baghouse filters. Data from particulate emissions monitors can be used in these cases to provide valuable process feedback information on plant operation and filter performance.
Humid Process Application:
PCME’s ElectroDynamic™ range includes a patented insulated sensing probe option for use in high humidity (non-condensing) gas applications, for unrivalled performance in humid processes including those found in gypsum plant such as after calciners. The insulated probe has been demonstrated to operate with minimum maintenance for extended periods with ‘sticky’ particulate matter caking the sensing probe, due to the unique ElectroDynamic™ measurement technique.
Range of Technologies:
PCME recognise that differing environmental conditions and process applications require different technologies to ensure maximised system reliability, to provide the most accurate emissions measurement, and to provide operators with data that facilitates process and arrestment plant management for reduced costs and maximised efficiency. Selecting the best technology for each application can mean considerably reduced maintenance and servicing requirements.
For electrostatic precipitator abatement plant, PCME offer a range of DynamicOpacity™ Ratiometric Opacity instruments which require significantly reduced maintenance compared to typical Opacity instruments. PCME’s DynamicOpacityTM technology also operates with heavy lens contamination of up to 90%, and the instrument is not damaged in the event of air purge failure. Bagfilter arrestment plant can be monitored by a networked system of ’s ElectroDynamic™ Probe Electrification instruments, certified to TUV and MCERTS performance standards with patented features for high performance under a wide range of process conditions.
Tolerance to Contamination
PCME’s unique and patented ’s ElectroDynamic™ Probe Electrification technology allows sensors to operate normally with significant contamination build-up on the sensor rod, avoiding the signal drift issues associated with traditional probe electrification type instruments and offering greatly reduced maintenance requirements. Additionally, PCME’s patented insulated sensor rod option offers unrivalled performance in high humidity (non-condensing) applications.
Advanced Probe Contamination Check
To provide the utmost confidence in the operation of PCME’s advanced particulate monitoring systems, a unique patented secondary contamination ring is utilised which monitors any leakage currents or signals across the insulator thereby proving the measurement integrity of the sensor at all times. This automated check of the sensors functionality eliminates the need for time consuming manual inspection of the unit, which is common with other monitoring techniques.
Network Integration:
Gypsum plant typically requires instrumentation across several emissions sources. PCME sensors can be networked into one central control unit, integrated with existing plant DCS/SCADA systems, and provide Ethernet connectivity for plant-wide LAN integration.
