cleaning and calibration of ph and ORP sensors on every paper machine was using a substantial amount of maintenance personnel s time.

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1 Pulp & Paper Perspectives in Liquid Process Analytics 19 News INGOLD Leading Process Analytics 200 % Increase in ph Electrode Lifetime Significantly Reduces Maintenance Pulp production is highly demanding on in-line sensors because of the harsh process conditions. Short ph and ORP electrode lifetime led a US mill to look for a better solution. METTLER TOLEDO s combined ph / ORP probe has resulted in substantial savings. Bleaching of paper tissue Our customer operates a large mill in the western United States where they produce paper tissue on 11 machines. In their bleaching plant, they use chlorine dioxide in elemental chlorine-free (ECF) delignification. In order to achieve the desired color of the final product, our customer needs to maintain ph at 4.5. They also measure redox potential during the process to monitor bleach strength. Poor performance from existing ph system High process temperatures and pressures proved harsh for the ph and ORP electrodes they were using, reducing their lifetime to only four to six weeks. In addition, cleaning and calibration of ph and ORP sensors on every paper machine was using a substantial amount of maintenance personnel s time. Combined ph / ORP electrode halves measurement points METTLER TOLEDO was asked to provide a better solution. We confidently put forward our InPro 3250 SG sensor, InFit 761 e housing, and M700 transmitter. The InPro 3250 SG is a pre-pressurized liquid-electrolyte ph electrode with inbuilt temperature sensor. The internal over-pressure ensures gradual electrolyte outflow, efficiently cleaning the sensor s diaphragm and preventing influx of process medium into the reference electrode. These features ensure long sensor life and

2 make the sensor highly suitable for bleaching applications. The SG at the end of the sensor s name denotes that it includes a solution ground. This takes the form of a platinum spot on the electrode s body. The platinum improves grounding and eliminates electrostatic interference. Significantly, it also allows ORP measurement in parallel to the ph measurement, and therefore halves the number of measurement points required on our customer s paper machines. To protect the sensors from damage from abrasive solids, the InFit 761 e housing with its protective cage was selected. The housing's very smooth surface finish prevents solids adhering, making cleaning easy. M700 transmitter Flexible transmitter The M700 multi-parameter transmitter is of modular design. Three internal slots allow the connection of specific modules for the measurement of a wide range of process parameters, plus a choice of communications module, making the M700 a highly flexible unit. Substantial cost savings Mill technicians are delighted with the performance of the METTLER TOLEDO solution. The combination of ph and ORP measurement in a single sensor has cut the number of measurement points on the paper machines by 50 %, and therefore considerably reduces time spent on maintenance. In addition, the long sensor lifetime, approximately three times that of the previously used probe, has reduced maintenance still further. If you want to improve the performance of your ph measurement points, go to: c InPro 3250 SG ph electrode Publisher / Production Mettler-Toledo AG Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Illustrations Mettler-Toledo AG Ligonography, Tinka, Eric1513, Imdan, Morenosoppelsa Dreamstime.com Subject to technical changes. Mettler-Toledo AG 01/13. Printed in Switzerland. 2 METTLER TOLEDO Pulp & Paper News 19

3 InTrac Housings Greater Process Integrity with Retractable Housings If you have processes that run over extended periods or where sensor contamination is a concern, retractable housings allow easy and safe sensor access without process interruption. That gives you increased process integrity and more uptime. Concept The idea behind InTrac retractable housings is to offer enhanced reliability and operational safety and increased process uptime, plus significantly reducing measuring point operating costs. InTrac housings have been designed for use in demanding applications in the pulp and paper industry where the use of ph / ORP, DO, conductivity, and turbidity sensors is necessary to monitor and control process conditions. High safety Central to the design of InTrac housings are the patented Tri-Lock safety features: sensor detector, safety immersion tube, and positive position locks. All of which have been designed to avoid unintentional release of process fluids. The sensor detector prevents the housing from being inserted without a sensor being installed. The immersion tube seals the housing from the process at all times during operation, and the positive position locks always keep the sensor in an optimal measuring position. Always reliable The protruding part of the immersion tube is free of O-ring sealings, as these are all fitted inside the housing and therefore not exposed to aggressive chemicals or fouling substances. Complete separation of the sealing and bearing functions improves operation and reliability, even in highly contaminating applications. In combination with an EasyClean sensor cleaning and calibration system, a fully automated measuring solution is available, bringing about a substantial reduction in operating costs. Flexible in installation A wide selection of process fittings enables InTrac 777 retractable housing unrivalled flexibility for any installation purpose. If process integrity and increased uptime are important to you, go to: METTLER TOLEDO Pulp & Paper News 19 3

4 ph Measurement and Cleaning System M400 transmitter Sensor Lifetime Quadrupled in Tall Oil Process A Swedish paper company experienced severe clogging and cleaning problems with their ph electrodes during tall oil production. Installing a METTLER TOLEDO ph measurement solution and automated sensor cleaning system has significantly prolonged electrode life and greatly improved measurement reliability. Leading supplier of packaging paper Our customer is a multi-national Swedenbased producer of container boards, and kraft and sack papers for the packaging industry. It has a world-leading position within several product segments such as medicines, luxury goods, and food and beverage. ph control in tall oil production During the sulfate process, lignin is separated from cellulose. The by-product, black liquor, is concentrated by evaporation and is then burned. Its inorganic portion is used to regenerate the sodium hydroxide and sodium sulfide needed for pulping. In conifer pulping, a soap-like substance is collected from the liquor during evaporation. The soap is transferred to an acidulator where it is heated and acidified with sulfuric acid to produce tall oil. The process temperature is 90 C (194 F) at atmospheric pressure. ph measurement and control is required as the ph value has to be lowered to ph 3 to 3.5 in order to initiate tall oil production. High concentration of solids Our customer had experienced clogging problems with the ph electrodes they previously used. Due to the presence of lignin and calcium sulfate, the electrodes continuously became blocked with solid precipitates and had to be replaced after only one or two days. The mill also had problems regarding cleaning of the electrodes. For purging of the lines with sodium hydroxide solution, the process had to be halted. This provided the opportunity to clean the electrodes. However, line purging does not take place on a fixed schedule; therefore, electrode cleaning often had to be conducted after electrodes were becoming clogged and ph measurement was no longer reliable. Customer s expectations Frustrated with the situation, mill technicians asked METTLER TOLEDO to install new equipment that would provide continuous, reliable ph measurements. The key to solving the problem was a system that would prevent solid build-up forming on the electrodes. 4 METTLER TOLEDO Pulp & Paper News 19

5 METTLER TOLEDO solution After carefully considering the process conditions and discussions with mill engineers, four complete systems comprising the following equipment were installed. ph electrode: InPro 2000 j Reliable performance at high temperatures j Outflow of electrolyte helps keep diaphragm clean j Refillable electrolyte extends operational life InPro 2000 ph electrode Retractable housing: InTrac 776 e j For electrode extraction without process interruption j Built-in flushing chamber for electrode cleaning and calibration j Tri-Lock safety system prevents escape of process fluid during electrode exchange Transmitter: M400 j Single-channel unit with multi-parameter ability j Accepts analog or digital ISM sensors j Quick set up mode for fast installation InTrac 776 e retractable housing Automatic cleaning / calibration system: EasyClean 350 e j Completely unattended ph electrode maintenance j User-configurable cleaning and calibration timing j Notification of need for buffer and cleaning fluid replenishment j Independent of M400 transmitter Long electrode lifetime and less maintenance Mill technicians report that the new system performs as expected and delivers reliable, continuous ph data. Consequently, our customer now obtains a higher quality of tall oil due to the more accurate measurements. Thanks to the EasyClean system, cleaning of electrodes is now very satisfactory. An initially suggested cleaning cycle of 10 minutes every hour was found to be unnecessary: cleaning the electrodes at 8-hour intervals has proved to be sufficient. Overall, the main benefits of the systems are the reduced replacement costs due to average electrode lifetime of four times longer than those previously used, and reduced labor costs for maintenance. If you need to keep ph measurement systems running at your mill, go to: c METTLER TOLEDO Pulp & Paper News 19 5

6 Vehicle Scale Service Make Time-Consuming Service a Thing of the Past Every minute spent repairing your vehicle scale is lost production time. POWERCELL PDX load cells protect your profits by keeping service to a minimum. In addition to providing unmatched reliability, they dramatically reduce the time it takes to do troubleshooting and replacement work. The first thing you can do to reduce unnecessary service is to select a load cell network with proven reliability. When it comes to preventing problems, your best bet is the POWERCELL PDX load cell network. It eliminates troublesome junction boxes and uses a built-in predictive diagnostics system to monitor network health. If a problem does occur, POWERCELL PDX load cells make solving it quicker and easier than ever. Load cell replacement Vehicle scales are often used in harsh environments, where there are many ways to damage a load cell. Every minute your scale is shut down to replace a damaged load cell can mean lost business. POWERCELL PDX load cells help you avoid those losses by speeding up the replacement process every step of the way. First, the predictive diagnostics system identifies the problem load cell quickly. In fact, it can alert you the instant a load cell is damaged. Other load cell systems often continue producing costly weighing errors for months before you notice something is wrong. Even then, time-consuming tests might be needed to locate the problem load cell. With POWERCELL PDX load cells, the predictive diagnostics system tells the service technician exactly which load cell needs to be replaced. Second, replacing a POWERCELL PDX load cell is a quick and easy job. Just disconnect the cables, jack up the scale, and remove the load cell. Then connect the cables to the new load cell, position it in the receiver, and lower the scale. Replacing other types of load cells can take much longer. Even the simplest analog Quick-locking connectors make it possible to replace a POWERCELL PDX load cell cable in minutes. system requires extra work, such as opening the junction box, routing the load cell cable, and wiring the cable to the terminals inside the junction box. Third, a POWERCELL PDX network requires very little setup. Just use the scale terminal s simple addressing procedure. In most cases, no adjustments are needed, so the scale is ready to weigh. If local weights and measures regulations require calibration, the job can be done in about an hour. Compare that with conventional load cells, which require numerous re-adjustments and can easily take a full day to calibrate. The POWERCELL PDX load cell network combines unequalled reliability with easy troubleshooting and replacement. Cable replacement POWERCELL PDX load cells use cables with quick-locking connectors that make replacement a snap. Just turn the connector slightly and remove it from the load cell. Plug the new cable s connector into the load cell and turn it until it 6 METTLER TOLEDO Pulp & Paper News 19

7 Best Practice Stop Downtime in its Tracks clicks into place. The watertight connection seals the network to IP 68 standards. As soon as the new cable is connected, the scale is ready to weigh. No recalibration is needed. Most other load cells have permanently attached cables. If a cable is damaged, you need to replace both the cable and the load cell. Instead of a simple cable replacement, you are faced with timeconsuming recalibration and the extra downtime it requires. Junction box replacement Since a POWERCELL PDX load cell network has no junction boxes, there s nothing to replace. That is not the case with conventional load cell systems. They all use some type of junction box, totalizer, or sectional controller to combine the load cell signals. Not only are these components the most frequent cause of vehi- cle scale failures, they are also difficult to troubleshoot. Once you have found the problem junction box, replacing it means disconnecting the wires for each load cell and for adjacent junction boxes. After the junction box has been replaced, recalibration is required. The biggest problem is moisture, and there are plenty of ways for it to enter a junction box. Most junction boxes have five or more openings for cables, with connectors that are tightened by hand. The lids are fastened with screws, so again you rely on hand tightening to seal out moisture. Stop wasting valuable time on repairs and recalibration. The POWERCELL PDX load cell network combines unequalled reliability with quick and easy service to keep your vehicle scale up and running. c Spend your time weighing vehicles, not servicing your scale. With its unequalled reliability and simplified service, the POWERCELL PDX load cell network is your most potent weapon in the fight against downtime. Visit our website to watch a video that shows how easy it is to replace a POWERCELL PDX load cell. c Replacing a conventional load cell, cable, or junction box requires time-consuming recalibration with heavy test weights. METTLER TOLEDO Pulp & Paper News 19 7

8 Cableless Solution Tricky Sensor Installation Point? Go Cableless! Proper wiring between sensor and transmitter can be very costly, especially in locations with limited access or where moving parts can be a hazard. The cableless solution W100 gives you the option to solve expensive and challenging installation conditions at a very reasonable cost. No more cables With the W100, METTLER TOLEDO offers an innovative solution for cost-intensive measurement point installations. Based on reliable and industry-proven wireless technology (according to IEEE ), the W100 replaces the cable between METTLER TOLEDO Intelligent Sensor Management (ISM) sensors and the transmitter, and provides bi-directional digital data transfer with full calibration and diagnostics functionality. Real-time monitoring of the measurement value as well as auto-recognition of the sensor is ensured. Additionally, the W100 convinces with its very simple one button operation, which is also the basis for the easy pairing between transmitter and sensor. Thanks to the LED display, the state of the W100 can be recognized at a glance. Installation at existing ISM measuring points is simple as there is no need to change any transmitter settings. tion. It is also the perfect answer for remote monitoring tasks. The W100 supports ISM sensors for ph, DO as well as 4-E conductivity, which are compatible with the advanced transmitter line M400 or the value transmitter line M300. Additional benefits of the cableless solution include the long battery lifetime of up to 6 months, and the communication range of up to 150 meters. Discover more at: Best Practice Stay one step ahead of maintenance with ISM A METTLER TOLEDO ISM measuring system with the W100 will not just save on installation costs; ISM also reduces the maintenance and calibration effort to a mimimum. This considerably improves process reliability, productivity and system availability. Find out how ISM can help you, at: For many applications Since there is no cable to be laid, the system offers great advantages in applications where high installation costs due to physical barriers or contamination risks, exist. Also, in applications where the measuring point is needed only temporarily, where the installation of the sensor has to be changed several times, or where the sensor is mounted on a moving part, the W100 is a highly cost-efficient solu- 8 METTLER TOLEDO Pulp & Paper News 19

9 Comprehensive Website The Information You Want is at The METTLER TOLEDO Process Analytics website contains a vast amount of up-to-date information on all our products and services. Content is localized for your country and tailored to suit your selections. Simple layout allows you to quickly find the information and features you are looking for. j Learn about our most recent product developments j Request further information on products and services j Obtain a quote quickly and easily j Read case studies relevant to your industry j Access buffer and electrolyte solution certificates j and more... j Read the latest product news j Access our newsletter archive j Find out when our next trade show or exhibition is in your area j Register for free webinars presented by our industry experts j Download our white papers METTLER TOLEDO Pulp & Paper News 19 9

10 InPro 7250 Conductivity Sensors No Clogging, no Maintenance Just Accurate Conductivity Measurement METTLER TOLEDO s inductive conductivity sensors combine high performance with low maintenance. The electrodeless design provides very accurate measurement in medium to highly conducting process fluids no matter how harsh the conditions. Conductivity sensors are invaluable in chemical dosing applications for pulp and paper production, and wastewater monitoring. However, standard designs can easily become clogged, necessitating regular cleaning. METTLER TOLEDO s InPro 7250 inductive conductivity sensors never clog and are highly resistant to coating. Their robust design ensures maintenance- and trouble-free operation. Find out more at: c Your benefits Choice of body materials for flexibility Available in PEEK for very aggressive chemical environments or in PFA where strong acids are present. Easy installation A variety of available process adapters allows simple installation into almost every type of process. Wide range of applications High linearity from 0 to 2000 ms/cm allows process control across a large variety of applications. 10 METTLER TOLEDO Pulp & Paper News 19

11 EN_07 InPro 7250 inductive conductivity sensors METTLER TOLEDO Pulp & Paper News 19 11

12 Get in-line with METTLER TOLEDO Easy Sensor Calibration with Free Maintenance Software Intelligent Sensor Management (ISM) is helping to improve productivity in process industry companies the world over. isense Asset Suite, the partnering software for ISM sensors, allows easy sensor calibration in a convenient location away from the process, sensor diagnostics for increased process uptime, traceability over a sensor's lifetime, and much more. A free version of isense, isenselight, has all the main features of the full software. No license is required and there is no need for registration. With isenselight, ISM sensors and transmitter, and an ilink USB cable you immediately get all these benefits: j Fast and easy sensor calibration in a convenient location j Predictive maintenance diagnostics j Configuration of optical oxygen sensors j Printable calibration reports c Mettler-Toledo AG Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Visit for more information