“Simplicity and Savings” Intelligent pH Sensors at a French Refinery In beet refining, reliable pH measurements are central to producing a high yield of good quality sugar. A combination of high-performance pH electrodes and Intelligent Sensor Management technology provides the perfect solution for Lesaffre. A family-run refinery Founded in 1873, the Lesaffre Sugar Re- finery in Nangis, France is an independent company that has been in the Lesaffre family since 1882. Each year, between September and December, 8,500 tons of sugar beets arrive daily at the refinery to be converted into sugar, syrup, molasses, pulp and pellets. After arriving on site, the beets are washed and cut into thin slices (cossettes) in order to facilitate juice extraction. This is fol- lowed by a diffusion step during which the sugar content in the cossettes transfers to hot water. Milk of lime and calcium hydroxide is then added to the diffusion juice to form calcium carbonate and to isolate certain impurities. Two carbonata- tions, each followed by filtration, comple- ment the liming. After the second filtra- tion, the obtained clear juice is then decalcified and evaporated to form crys- tallized sugar. A process prone to clogging pH probes For high yield production of good sugar, various parameters must be monitored and controlled during the processes. Ac- cording to the refineryʼs production manager, Mr. Laurent Dezusinge, “pH measurement is a key parameter, in par- ticular during the diffusion and carbon- atations.” In the diffusion water, tight control of pH is important to maintain the acidity re- quired for maximizing cossette permea- bility, and to prevent bacterial contamina- 26 News Sugar Starch & Yeast Perspectives in Liquid Process Analytics INGOLD Leading Process Analytics
Transcript
“Simplicity and Savings”Intelligent pH Sensors at a French RefineryIn beet refining, reliable pH measurements are central to producing a
high yield of good quality sugar. A combination of high-performance pH
electrodes and Intelligent Sensor Management technology provides the
perfect solution for Lesaffre.
A family-run refineryFounded in 1873, the Lesaffre Sugar Re-finery in Nangis, France is an independent company that has been in the Lesaffre family since 1882. Each year, between September and December, 8,500 tons of sugar beets arrive daily at the refinery to be converted into sugar, syrup, molasses, pulp and pellets.
After arriving on site, the beets are washed and cut into thin slices (cossettes) in order to facilitate juice extraction. This is fol-lowed by a diffusion step during which the sugar content in the cossettes transfers to hot water. Milk of lime and calcium hydroxide is then added to the diffusion juice to form calcium carbonate and to isolate certain impurities. Two carbonata-tions, each followed by filtration, comple-
ment the liming. After the second filtra-tion, the obtained clear juice is then decalcified and evaporated to form crys-tallized sugar.
A process prone to clogging pH probesFor high yield production of good sugar, various parameters must be monitored and controlled during the processes. Ac-cording to the refineryʼs production manager, Mr. Laurent Dezusinge, “pH measurement is a key parameter, in par-ticular during the diffusion and carbon-atations.”
In the diffusion water, tight control of pH is important to maintain the acidity re-quired for maximizing cossette permea-bility, and to prevent bacterial contamina-
26News
Sugar Starch & YeastPerspectives in Liquid Process Analytics
tion. This stage happens at high temperature with a strong presence of sulfur and many deposits that can make pH measurement problematic.
Liming and carbonatation are the two most critical stages of beet refining, but generate a great deal of calcium carbonate that can clog equipment. “Sugar produc-tion from beet is a highly fouling process that occurs at high temperatures. There is the difficulty of measuring pH,” says Mr. Dezusinge. pH control is so critical for effective juice purification that the mea-surements are often doubled to secure the process, as is the case at Lesaffre.
High maintenance costs of antimony probesFor the pH measurement itself, Lesaffre was using antimony pH sensors with a motorized scraper ring that would peri-odically remove fouling from the probes. Mr. Dezusinge was unhappy with the costs of maintaining the motorized parts and was concerned that antimony electrodes could become obsolete. He required a bet-ter solution and drew up a list of require-ments:• Repeatable and reliable results with
an accuracy of 0.25 pH units• Simple installation and configuration• Easy maintenance with less sensor
cleaning• Long sensor life to reduce costs
A sensor designed to tolerate sugar processesMETTLER TOLEDO proposed to Mr. De-zusinge a complete measurement system based around our InPro 4800 i pH sensor. This electrode is equipped with a very long diffusion path in a double electrolyte chamber and a PTFE-coated junction. Thanks to these characteristics the InPro 4800 i exhibits very good resistance to sulfur contamination, temperature toler-ance up to 130 °C, and due to the PTFE coating of the junction, measurements are ensured even in the most sticky environments.
Additionally, the probe design has a flat glass membrane that is less susceptible to abrasion damage in process media with a high solids concentration. An annular cap made of PEEK protects the mem-brane against direct impact with- out inhibiting measurement performance.c www.mt.com/pro-solid- solution
Designed to tolerate industrial environmentsDespite the best efforts, accidents happen. If a glass pH sensor breaks it can risk staff and production safety. METTLER TOLEDO has now introduced rugged sen-sors designed to withstand the common everyday knocks that happen in industrial operations. The InPro 4281 i and 4881 i are the first 12 mm pH sensors featuring a titanium shaft. The sensors are not only physically robust but also chemical and abrasion resistant. The InPro 4281 i and 4881 i probes are fastened with a 316 stainless steel threaded nut, replacing the plastic one on conven-tional probes.
Titanium Shaft pH Sensors A Solid Solution
NEW
ISM® is the icing on the cakeAnother feature of the sensor, Intelligent Sensor Management (ISM), provides ad-ditional valuable benefits:• High signal stability due to digital
communication between sensor and transmitter.
• Dynamic Lifetime Indicator continu-ously monitors sensor condition and predicts when replacement will be required.
• Adaptive Calibration Timer estimates the time remaining before the next calibration should be performed.
• iSense PC software enables sensor cal-ibration away from the process in any convenient location and provides cali-bration reports in PDF format.
Greater process reliability and less maintenanceFollowing a very successful test period, the METTLER TOLEDO solution was installed in place of the old equipment. Now, compared with the previous systems, maintenance is much lower, calibration is simplified and pH-critical processes are running with greater reliability.
Mr. Dezusinge appreciates not only the performance of the InPro 4800 i sensor, but also the ease of use of the ISM platform and the reduced operating costs it real-izes. He said, “I can summarize the ISM approach in two words: simplicity and savings.” He has since decided to install the METTLER TOLEDO solution to replace all pH measurements at the plant.
in Sugar Cane and Alcohol MillsThe importance of controlling pH in sugar and alcohol mills is well accepted, but it is not
the only process parameter that should be regulated. Using conductivity measurement to
control the quality of pure water fed to boilers and produced during purification will lead
to less maintenance and more efficient boiler operation.
Measuring water puritypH control is perhaps the most critical analytical factor in sugar cane refining. Nonetheless, other analytical parameters play a significant role in efficient mill operations. Conductivity measurement is a very common parameter monitored in sugar as well as alcohol mills. Two ap-plications that are most prevalent are, analyzing water quality during reverse osmosis purification for power cogenera-tion, and monitoring the return of con-densed water to the boilers. Both applica-tions involve low conductivity values, which is best measured with 2-electrode conductivity sensors.
Ensuring quality of boiler feedwaterIt is common to find power cogeneration technology employed in the sugar and alcohol industry. This is largely due to the cheap and readily available cane bagasse that can serve as fuel for the steam-gener-ating boilers. The water used in the boiler must be very pure, i.e. free from ions ca-pable of forming insoluble salts that can build up in the boilersʼ pipes. Salt deposits in the piping lowers thermal efficiency and can potentially cause accidents.
Consequently, before feeding the boilers the water must undergo treatment (re-
verse osmosis and deionization with ion exchange resins). Measuring conductivity after treatment will verify purity and allows water that does not meet the re-quired standard to be diverted for further processing. The water should have a conductivity ranging between 0.5 and 10 μS / cm after reverse osmosis or demin-eralizing treatment.
Monitoring of condensed waterThe condensate of the steam generated by the boilers is continuously reused. This requires carefully controlled conditions for maximum efficiency and longevity of the equipment. Using conductivity to evaluate water quality is cost-effective and very reliable. The ideal conductivity value for this application is 20 – 50 μs / cm at approximately 100 °C.
A conductivity measurement system highly suited to both applications comprises:
InPro 7001 sensorTwo-electrode sensor designed for high accuracy measurements in very low to medium conductivity waters. The factory-determined cell constant for maximum accuracy allows the most efficient control of water quality.
Temperature measurement with a built-in sensor is fast and precise, and provides assurance of correct conductivity readings at the transmitter.
M400 transmitterThe M400 is a single-channel, multi- parameter unit that accepts analog or digital Intelligent Sensor Management (ISM) sensors. pH / ORP, oxygen as well as conductivity are covered by the transmit-ter, allowing the M400 series to be speci-fied throughout a facility. This reduces the training requirement and risk of operator error.
InFit 761 housingA highly versatile housing available in a wide range of materials and insertion
lengths to suit a diverse array of applica-tions. Rugged design ensures durability in demanding refinery environments.
METTLER TOLEDO conductivity mea-surement systems can be assembled from a wide range of sensors, housings, transmitters and process connections, depending upon specific case-by-case re-quirements. A standard configuration has been discussed above, which usually meets the requirements for conductivity measurement in the applications men-tioned. However, METTLER TOLEDO
technical representatives can provide ad-ditional information for more specialized applications.
The InTrac 781 / 784 series of retractable sensor housings combine rugged design with installation versatility to meet the demands of the toughest conditions in sugar and starch applications.
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for the Harshest ProcessesTo give you more production uptime, sensor housings must not only be
process tolerant, they must also provide ease of use and ensure trouble-
free operation. All these elements were considered when designing our
new InTrac housings. The result is our most advanced housings yet.
High reliability combined with low main-tenance and ease of operation help keep production running. While advanced safety features protect operators and the plant environment at all times.
Sensor cleaning out of your handsReliable measurements demand that sensors are kept free from build-up from particles. The new InTrac housings contain four integrated spray nozzles and a large bore cleaning chamber to ensure particles are efficiently flushed away.
Depending on the operating system, backwash flushing of the sensor is possible as soon as the sensor is retracted from the process.
Operation with EasyClean systems enables fully automatic sensor cleaning, flushing and calibration (for pH sensors) – giving engineers more time for other tasks!
Keep processes runningThe housing design allows sensor inspection, cleaning, calibra-tion or exchange at any time without the need for stopping the process. And the advanced drive train allows insertion or retrac-tion of the sensor in process pressures of up to 16 bar!
An intelligent sensor locking system prevents deployment of the insertion rod if no sensor is present in the housing.
InTrac 781 R(pneumatic / with inductive check-back)
InTrac 781 M(manual)
InTrac 784 R(pneumatic / with inductive check-back)
InTrac 784 M(manual)
Flexible to your needsTo suit the range of conditions in sugar and starch production, wetted parts are available in different materials, i.e. stainless steel 1.4404 / SS 316 L; Alloy C-22; PP, PVDF or PEEK. Various immersion lengths (80 mm or 280 mm) and types of process connection (flanges- DIN, AISI, or NPT) are available, providing excellent installation flexibility at the measurement point.
No compromise on safetyInTrac 781 / 784 housings meet the strict requirements of major international guidelines including ATEX, so the housings can be safely operated in Ex-classified environments.
The intelligent sensor locking system and visualized sensor posi-tion rod provide additional information on sensor status, enhancing operational safety. In addition, it is not possible to remove the sensor when the housing is in the measurement position.
An inspection window allows operators to visually check the status of seals.
Prevent Fraud at Your ScaleTurning a profit is hard enough without having to contend with fraud. If you buy and sell
truckloads of material by weight, there are a surprising number of ways you can be cheated.
Vehicle-scale software with built-in security features can protect your profits by preventing
fraud at your truck scale.
The stakes can be high. In a recent case, cheaters defrauded a major international agribusiness company of $ 2 million. The scheme involved a scale operator conspir-ing with suppliers to create bogus tickets for grain shipments that were never made. In this case, the theft continued for years. Without a system capable of detecting fraud, a company can do little except hope that someone notices a discrepancy in inventory levels before too much money is lost.
While scale operators are in a good posi-tion to spot cheaters, they also have plenty of opportunities to cheat. By using Data-
Bridge™ MS software and taking a few simple precautions, you can protect your business.
Beyond passwordsMost software programs are limited to password protection. The problem with those programs is that anyone with a password is free to use or misuse the ap-plication. Although defining access levels for individual users helps, it will not stop the determined cheater from defrauding you.
It takes more than password protection to stop an authorized scale operator from
cheating. DataBridge™ MS software has a tamper-proof audit log that provides a permanent record of all transactions and all changes to the database. It tracks activ-ity at your scale and identifies the user who was logged in at the time. When scale operators cheat, they risk leaving a com-plete record of their fraudulent activity.
Using bogus tickets or tare weights is a common way to steal from a company. Instead of processing an accurate transac-tion for a load, a scale operator can reprint a ticket from a previous transaction. DataBridge™ MS software allows the person who issues payment for tickets to view a complete record of every transac-tion, including a record of how many times a ticket was printed. The software also stores a history of tare weights for indi-vidual vehicles to let you know if a scale operator is changing tare weights in order to shortchange the company.
Unattended weighingUnattended scales are a tempting target for drivers who want to cheat. With no scale operator to keep them honest, drivers can use their trucks to manipulate weight readings. To decrease a weight reading, they position a truck with one or more axles off the scale. To increase a weight reading, they work with another driver who positions the front wheels of a second truck on the back of the scale.DataBridge™ MS software helps catch cheaters by using a weight curve to verify that each transaction
There are several ways to prevent this type of activity. The software can be connected to traffic loops and photo-eye sensors that control gates to regulate traffic across a scale. It also has a feature that automati-cally aborts a transaction if a second truck drives over a traffic loop while a transac-tion is in progress. By using cameras, the software can capture photographs that show exactly how a truck is positioned at various stages of a transaction. Cameras can also identify trucks by focusing on license plates or drivers.
Catching cheatersCheaters have become increasingly so-phisticated and hard to detect. Electronic devices are available to give truck drivers remote control of a scale. The driver simply pulls onto the scale and then uses the device to increase or decrease the weight reading.
To catch these cheaters, DataBridge™ MS software uses a weight curve. The software plots a graph of vehicle weight throughout each transaction. During a legitimate transaction, weight will increase gradu-ally as a truck pulls onto the scale and level off when the truck stops moving. If a driver or scale operator manipulates the
weight electronically, the weight curve will show a spike up or down to indicate the sudden weight change.
No company is immune to cheating or theft. Use DataBridge™ MS software to ensure that your truck scaleʼs weighing transactions are trustworthy.
c www.mt.com/DataBridge
c www.mt.com/veh-fraud-prevention
Stop the CheatersLearn about the top five ways that criminals cheat at truck scales. A new white paper about fraud pre-vention reveals the five most com-mon scams and shows you how to stop the cheaters cold.
Visit the METTLER TOLEDO web site and download the free fraud-pre-vention guide.
Small Footprint – Big PossibilitiesHead Mount Transmitter
With the M100 Head Mount, METTLER TOLEDO offers the world’s first
transmitter for analytical measurements based on a compact, head
mount design. It also features an explosion proof / flameproof enclosure
and intrinsically safe electronics for both hazardous and non-hazardous
area installation.
and continue to require a transmitter large enough to include keys and a display due to their frequent need for calibration. METTLER TOLEDO has defied this convention. With the M100 Head Mount, METTLER TOLEDO offers the world‘s first com-pact, head mount transmitter for analytical measurements.c www.mt.com/M100
The average production facility con-tains hundreds or even thousands of field instruments, most of which are of the “fit and forget” type. They go unnoticed due to their inconspicuous design and absence of a local human machine interface.
Analytical sensors, on the other hand, have not followed this trend
Your benefits
Simple Plug and Measure operationWith iSense, the key tool of Intelligent Sensor Management (ISM®), sensors can be pre-calibrated via a PC or porta-ble device then connected to the M100. Therefore, a user interface in the field is no longer necessary.
Predictive maintenanceEasiest handling and on-site or remote access over HART to advanced ISM pre-dictive diagnostics tools leads to reduced maintenance costs and increased pro-cess uptime.
Low installation costsRugged construction and compact design allow direct installation next to the pro-cess. M100 offers a versatile solution for both hazardous and non-hazardous area installations.
Sensors That LearnGive You the Most Reliable Diagnostics
To maximize product quality and yield, you need to know if your sensors are performing correctly. That is why we have always made diagnostics the main focus of Intelligent Sensor Management (ISM®). And with our new version of ISM we offer a world’s first – sensors that actually learn from your processes to give you unequalled diagnostics performance.
