Highest Assurance of Water and Steam Purity Advanced Sodium Analyzer

Transcription

1 Power Generation Perspectives in Pure Water Analytics 18 News THORNTON Leading Pure Water Analytics Highest Assurance of Water and Steam Purity Advanced Sodium Analyzer Reliable, automatic on-line analysis of sodium in water and steam samples helps prevent damaging corrosion and deposits in power plant pure water systems and steam turbines. Thornton s new sodium analyzer provides the highest confidence in water / steam purity. Sodium level is key to water purity In the power plant, long-term efficient generation depends on minimizing corrosion and deposition within the steam / water cycle. As a leader in meeting stringent deionized water quality requirements with other measurements, METTLER TOLEDO Thornton has expanded its portfolio to include sodium measurement, the key parameter for initiating regeneration of cation exchange resin and for assuring water purity. The Thornton 2300Na sodium analyzer offers a new design for a traditional measurement for pure water treatment and power cycle chemistry monitoring. This analyzer provides assurance of water purity to minimize corrosion and maximize water production. Early detection of trace contamination is enabled with minimal operator supervision. Early detection of sodium contamination is critical Sodium is responsible for corrosion in high-value turbine blades and other parts of the cycle. Early detection of contamination allows time for planning corrective action before condenser leaks enlarge and serious damage occurs. The design of the Thornton 2300Na sodium analyzer is based on extensive instrumentation experience and is optimized to handle these measurement challenges. The new sodium analyzer uses a particularly simple automatic calibration method and also provides the ability to measure

2 grab samples easily, in addition to measuring pressurized samples from process streams. Its implementation with an operator interface common to other parameters including conductivity, dissolved oxygen, ph, TOC and ORP makes it especially convenient for installation and operator training. According to Thornton s senior product manager and power industry specialist David Gray, This analyzer s automatic sensor recognition system is a 2300Na sodium analyzer ground-breaking measurement and maintenance concept that improves accuracy, simplifies sensor handling, enhances reliability and reduces sensor life-cycle costs. Features and benefits: j Fully automatic, unattended calibration assures reliable operation while saving time j Reagent addition confirmation by ph to secure consistent measurement results j Convenient grab sample measurement for additional samples and quality control checks from other areas of the plant j Simultaneous display of sodium, adjusted ph, temperature and calibration progress provides convenient analyzer and sample status at a glance j Choice of enclosures: fully enclosed and lockable for dirty plant environments or partially-enclosed with accessible controls for clean sample rooms j Four analog outputs for sodium, adjusted ph and temperature with choice of scaling to enable full integration into data acquisition or control systems For more information, visit: c Publisher / Production Mettler-Toledo AG Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Illustrations Mettler-Toledo AG Santee Cooper American Electric Power Subject to technical changes. Mettler-Toledo AG 01/12 Printed in Switzerland. 2 METTLER TOLEDO Power News 18

3 Monitoring Total Organic Carbon TOC Measurement with Predictive Diagnostics New 5000TOC i Sensor Thornton s 5000TOC Sensor detects trace organic contamination levels accurately and swiftly. Now, with the addition of Intelligent Sensor Management (ISM) technology, analyzer performance is improved and maintenance reduced. Reliable, continuous TOC monitoring For power generation makeup water treatment - from reverse osmosis to demineralizers - the new Thornton 5000TOC i Sensor provides fast, reliable monitoring of total organic carbon contamination in the water system. Organic contamination can be detected before it enters the steam cycle where its breakdown to organic acids can accelerate corrosion and potential damage. Multi-parameter advantage Thornton 5000TOC i Total Organic Carbon Sensor with ISM delivers the power of an analyzer with the convenience of a sensor. The 5000TOC i Sensor with M800 multi-parameter transmitter provides a user-friendly and economical analytical package. It enhances operational performance with a dependable, sophisticated, intuitive TOC measurement system by combining a proven TOC analysis platform with an advanced user interface with extensive system diagnostics. Mix-and-match sensor capability The M800 transmitter is available in twoor four-channel versions. The two-channel version can accept one or two TOC sensors, or TOC plus one other parameter. The four-channel version can accept up to three parameters in addition to TOC, including conductivity, ph, ORP, dissolved ozone or dissolved oxygen, plus two pulsed flow sensors. Benefits of the new 5000TOC i Sensor: j Improves the quality and reliability of calibration with a semi-automated process which assures consistent results j Enables proactive maintenance through convenient diagnostics and sensor status data on intuitive imonitor user interface j Simplifies maintenance processes with in-depth diagnostic data, provided by detailed sensor status screens j Automated Flow Control improves the reliability of continuous, real-time TOC analysis by eliminating sensitivity to system pressure changes j 5000TOC i with M800 reduces overall cost, complexity and footprint of instrumentation j Multi-parameter capability integrates TOC measurement with a comprehensive UPW monitoring system with up to four sensors For more information visit: c METTLER TOLEDO Power News 18 3

4 Digital Sensors An Intelligent Decision Santee Cooper Converts to ISM Sensors When a major electricity producer wanted to upgrade sample panel equipment at one of their generating stations, they decided to install Intelligent Sensor Management (ISM) solutions. They are now benefitting from greater sensor reliability, accuracy and convenience. Natural gas-fueled plant produces 1100 megawatts Rainey Generating Station in Iva, South Carolina, USA is one of five generating stations owned by Santee Cooper, the second largest publicly-owned electric utility in the United States, serving over 2 million customers through its electric cooperative. This clean, natural gas-fueled combined-cycle power plant can produce up to 1100 megawatts. Conversion from analog to digital sensors When the plant began operation in 2001, engineers installed a commercially available sample panel equipped with METTLER TOLEDO Thornton 200PH and 200CR analog transmitters with ph and conductivity sensors. Although these instruments provided satisfactory performance for ten years, laboratory personnel found it challenging to isolate a problem if one occurred. After reviewing competitive products, Thornton digital M300 transmitters, conductivity and ph sensors with Intelligent Sensor Management (ISM) were selected for installation. Upgrade to digital sensors reduces space requirements and complexity Rainey Generating Station s water laboratory personnel installed the new digital instruments in the existing water panel, which serves the boiler water and steam system. A convenient plate covers the existing openings to accommodate the smaller ¼-DIN M300 transmitters. According to laboratory analyst Sam Hammond, The Thornton digital instruments are attractive, easy to read and calibrate. In addition, calibration and diagnostic data is stored in the head of each sensor, so recalibration is not required if sensors are moved or replaced. By the end of 2010 the plant had upgraded the instruments. Multi-parameter transmitter and digital sensors offer Plug and Measure convenience Thornton M300 ISM transmitters measure one or two channels of conductivity, resistivity, ph, ORP, or dissolved oxygen using ISM with Plug and Measure for fast measurement point start up, and advanced integrated sensor diagnostics. This multiparameter capability reduces the number of instruments and panel space required. Versatility in installation includes the choice of ¼-DIN panel-mount or ½-DIN wall- and pipe-mount enclosures. Sensors can communicate with the transmitter up to 91 meters (300 feet) away without further amplification, providing additional mounting flexibility. Older analog model transmitters were upgraded to Thornton M300 digital ISM transmitters and sensors. Measurement and control is critical to maintaining proper water chemistry in boiler tubes and steam turbines. The Rainey Generating Station water system also measures oxidation-reduction potential (ORP) with Thornton sensors, and dissolved oxygen (DO) is measured with 4 METTLER TOLEDO Power News 18

5 existing instruments. Laboratory personnel are pleased with the digital changeover and indicated that Thornton is a leading choice when upgrade of process analytical instruments is required. If you want to benefit from increased sensor reliability, accuracy and convenience at your plant, go to: c Benefits of digital ISM sensors Intelligent Sensor Management (ISM) is a unique technology developed by METTLER TOLEDO to expand sensor performance while simplifying installation, operation and maintenance. ISM technology stores unique sensor identification and calibration information in a digital sensor for immediate recognition to provide fast error-free start up. In addition, measurement accuracy can be improved with stored calibration data to ensure the most accurate measurements available. Maintenance is also simplified with predictive service notifications which allow for proactive maintenance to save time and costs. Dynamic diagnostics tools enhance sensor performance and prevent downtime. Along with the measuring circuit, ISM integrated sensors include non-volatile digital memory to maintain all identification, calibration and diagnostic data needed for user-friendly operation and documentation. Such details as measurement parameter, part number, serial number, factory calibration data and date, user calibration data and date, and diagnostic factors are available to the readout instrument for immediate recognition as soon as the sensor is connected. A user does not need to enter conductivity and temperature calibration constants or other data into the transmitter at start up. The result is the convenient ISM Plug and Measure function and greater operator convenience. For further information visit: c METTLER TOLEDO Power News 18 5

6 Conductivity Measurement Thornton boiler water conductivity sensor Protecting Condensate Quality High-Temperature Conductivity Sensor A selective catalytic reduction system requiring steam to generate ammonia risks contamination of the steam condensate. A Thornton high-temperature conductivity sensor guards against this threat and contributes to plant safety at American Electric Power. Environmentally friendly coal-fired power plant The American Electric Power Mountaineer Plant in New Haven, West Virginia, is a large coal-fired plant equipped with selective catalytic reduction (SCR) to minimize nitrogen oxide (NOx) emissions. SCR requires that large amounts of ammonia be added to the flue gas to achieve this air pollution control. However, the transport and storage of large volumes of ammonia pose a significant safety hazard. The Mountaineer Plant therefore chose to use an ammonia-ondemand system that reduces these hazards. Potential organic contamination averted with Thornton sensor The ammonia-on-demand system uses the more benign urea which is heated in order to break it down and release ammonia. The condensate of the steam used to heat the urea is vulnerable to contamination if there are any leaks in the heat exchanger. Such leaks would result in urea entering the condenser and conta m inating the entire feedwater stream, resulting in organic fouling, acid formation and corrosion. AEP determined they needed to measure conductivity to detect any urea leakage into the condensate. However, the condensate at this point was still at 14 bar (200 psi) and 170 C (340 F), well above the operating conditions of conventional conductivity sensors and there was no cooling water available for sample cooling at the measurement location. Successful sensor evaluation AEP personnel selected the Thornton boiler water conductivity sensor to meet this measurement challenge. To evaluate it under high temperature / pressure conditions, they first installed the sensor in their deaerator discharge line along with a Thornton M300 transmitter. After successful evaluation there, they moved it to the SCR ammonia-on-demand condensate line where it has operated reliably ever since. The M300 output signal is sent to the control room for visibility and alarm, and if the conductivity is too high, to close a valve that diverts the condensate to prevent contamination. Additional boiler conductivity applications The Thornton boiler water conductivity sensor is highly suited to this application; wetted materials of 316 stainless steel and PEEK polymer with robust seals provide a significant safety margin beyond its ratings of 17 bar (250 psi) at 200 C (392 F) and 35 bar (500 psi) at 25 C (77 F). The sensor and transmitter provide temperature compensation across the full range. In boiler operation, the evaporation of steam leaves behind increasing concentrations of minerals in the water that become corrosive or scale producing. Corrosion leads to boiler tube failures, downtime and expensive repairs. Scaling of heat transfer surfaces decreases thermal efficiency. The boiler water conductivity sensor is suitable for measuring hot condensate from other auxiliary steam uses, auxiliary boiler blowdown, or similar high temperature samples, especially where sample cooling water or a drain is not available. The boiler sensor combined with a Thornton transmitter with its selection of internal control options, provides a continuous, accurate conductivity measurement with readout in μs / cm, ms / cm or ppm TDS. The transmitter can be located up to 61 m (200 ft) away from the sensor (alarm, control and / or analog signals can be located even further). Automatic blowdown control with a Thornton system allows close management of boiler water quality and can reduce total blowdown, saving a significant amount of energy and waste. Find out more at: c 6 METTLER TOLEDO Power News 18

7 Water Cycle Chemistry Combatting Corrosion in Power Plants With Analytical Sensors In the US alone corrosion is a 10 billion dollar problem. Water cycle chemistry control via analytical measurements is vital for minimizing the effects of dissolved oxygen, sodium and other contaminants. METTLER TOLEDO Thornton s portfolio of sensors and analyzers with Intelligent Sensor Management technology help ensure ideal water conditions are being maintained. Corrosion is a huge drain on profitability Corrosion problems at power plants cost billions of dollars annually. Materials expenditure and loss of integrity and reliability are only part of the cost. The gradual loss of efficiency as corrosion products build up on heat-transfer surfaces gradually cause deterioration of heat rate and competitive generation capability. Contamination, corrosion and deposition of corrosion products are common problems in boilers and feed water piping and they are the cause of many forced outages and plant shutdowns. Analytical measurements for water cycle chemistry control Corrosion and deposits can be avoided through appropriate water cycle chemistry control which, in turn, depends on analytical measurements such as specific and cation conductivity, sodium, ph and dissolved oxygen. METTLER TOLEDO Thornton s product portfolio covers all these measurement requirements. Our sensors and analyzers for power plant water systems combine high operational performance with Intelligent Sensor Management (ISM) technology for ease of handling and simplified maintenance. Benefits of Thornton instrumentation include: High measurement accuracy j Factory-certified and traceable conductivity cell constant and temperature calibrations j Calculated ph from specific and cation conductivity, which eliminates electrode errors j Industry-proven temperature compensation, especially for cation conductivity and ph Measurement stability and reliability j ISM sensors with built-in measuring circuit and digital output that eliminate electrical interference j Conductivity sensors with wide electrode spacing with a relatively high 0.1 cell constant that resists fouling Low maintenance j Automatic, unattended calibration of sodium analyzer j Predictive diagnostics give a dynamic indication of sensor time to maintenance or replacement j Low maintenance ph sensors with self-pressurized reference electrode, with no electrolyte to refill j DO sensor with simple drop-in replacement membrane Discover more at: c METTLER TOLEDO Power News 18 7

8 Intelligent Sensor Management New Instrumentation Trends for Water Analysis Integration of the measuring circuit, calibration and diagnostics into a single compact sensor is a rapidly growing trend. The advantages of such intelligent sensors are discussed in this extract from Power magazine. Integrated sensors with Intelligent Sensor Management (ISM) The integration of the measuring circuit, calibration and diagnostics memory plus analog-to-digital conversion into compact electrochemical sensors is a rapidly growing trend. ISM sensors for conductivity, ph, ORP, temperature and dissolved oxygen have been in use for a few years. They offer a number of practical advantages. These sensors can be calibrated conveniently and reliably in the laboratory and retain their calibration data in memory when they are installed out in the process. ISM sensors with built-in diagnostics that are subjected to harsh conditions can provide automatic real-time indication of their condition and enable predictive maintenance. For example, this type of ph sensor exposed to hot alkaline boiler blowdown sample can integrate the time, temperature and ph level of its exposure to predict how much of its life remains. Locating the measuring circuit within the sensor has proven especially beneficial for conductivity measurement where the problems of transmitting AC signals long distances are eliminated. The significant capacitance and resistance of long lead wires limit the conductivity sensor / transmitter separation distance and the accuracy of measurement with traditional sensors. One type of ISM sensor, Thornton s UniCond conductivity sensor, takes full advantage of the closely coupled and improved measuring circuit to achieve unprecedented range capability. It can measure conductivity from ultrapure water to sea water with a single sensor while providing the highest available accuracy in pure water ranges. This kind of performance has obvious advantages in makeup water treatment that is not possible with traditional sensors. Other ISM sensors such as ph and dissolved oxygen gain the benefit of encapsulating their very low level signals right at the source. This encapsulation eliminates measurement errors caused by insulation leakage, lead wire flexing and static charges imposed on the signal. In addition, transmitting a robust digital signal a long distance back to the instrumentation panel prevents electrical noise interference from more remote sources. Automatic calibration With power plant chemists and technicians being required to do more with less, automated on-line process instrumentation is a welcome tool. Automatic calibration is especially worthwhile where the calibration process requires an extended period for equilibration to low concentrations such as with sodium and silica measurements. Unattended automatic calibration based on an internal timer in the METTLER TOLEDO Thornton 2300Na sodium analyzer relieves the technician of significant weekly or monthly tasks while providing perfect repeatability of calibration conditions. Service consists mainly of replenishing calibration standard solutions and reagents. It is anticipated that unattended automatic calibration will become more widely used as a valuable time-saver. Excerpt published with permission from Power magazine September 2011, pp by David G. Daniels, M&M Engineering Associates, with contribution by David Gray of Mettler-Toledo Thornton Inc. For more information, visit: c 8 METTLER TOLEDO Power News 18

9 Online Resource Keep Up-to-Date New Power Generation Competence Center Thornton is dedicated to continuous improvement in producing instruments for the detection of impurities in power plant water systems. A new online resource keeps you informed as to our latest developments in monitoring and measuring pure water and steam in power generating facilities. Essential monitoring of high purity water The life-blood of the power plant requires careful surveillance to guard against corrosive and depositing conditions, especially in turbine blades and boiler tubes. Long-term efficient power generation depends on minimizing corrosion and deposition within the steam / water cycle. Controlling high purity water treatment is only possible using sensitive and accurate analytical instrumentation. METTLER TOLEDO Thornton is recognized as the industry leader for on-line measurements for makeup water treatment and is growing rapidly for cycle chemistry monitoring. The latest information Thornton has extensive expertise in power applications, with proven capabilities for measurements of specific and cation (acid) conductivity, ph, oxidation reduction potential (ORP), dissolved oxygen and total organic carbon (TOC), for make-up water, cycle chemistry and stator cooling. Sodium and silica measurements will be available in 2012 for these applications. Learn more about in-line measurement solutions, featuring the unique Intelligent Sensor Management (ISM) concept for plug-and-measure convenience in analytical measurement. Featured on this new website are resources to help you choose instrumentation for: j Makeup water treatment including pre-treatment, reverse osmosis and deionization j Cycle chemistry Thornton expertise for these measurements includes intuitive multi-parameter transmitters and sensors, ease of calibration and lowvolume sensor housings that help prevent accumulation of corrosion products j Other water uses Auxiliary water uses present challenges in maintenance of sensors while obtaining results that satisfy regulatory requirements and corrosion constraints. Thornton sensors excel in difficult measuring conditions. Also highlighted are: j Products and solutions Find out how Thornton provides accuracy, flexibility and low cost of operation for water chemistry measurements j Documentation and know-how Download documents related to power generation and pure water measurement j Watch the informative video entitled Sodium Measurement Enhances Power Plant Water Chemistry, highlighting the new 2300Na sodium analyzer (available in 2012) Visit the new resource site Process Analytics for Efficient Power Generation at: c METTLER TOLEDO Power News 18 9

10 M800 Transmitter Predictive Maintenance Intelligent Sensor Diagnostics The multi-parameter, multi-channel M800 transmitter platform covers all major measurement parameters in one instrument. Intelligent Sensor Management (ISM) technology offers predictive diagnostics for proactive maintenance. The M800 transmitter for ISM digital sensors incorporates a highly intuitive user interface, expanded measurement parameters and, most significantly, diagnostic maintenance capabilities. imonitor is an advanced sensor diagnostics utility. It anticipates maintenance intervals based on real-time sensor performance information rather than sensor failure alarms or imprecise estimates. imonitor evaluates each sensor s condition and calculates remaining sensor (or integrated consumable) lifetime to predict when service or replacement will be necessary. The number of days until maintenance should be performed is displayed on the M800 with a red, yellow or green indicator bar, providing at-a-glance information based on traffic light color coding. c Your benefits Intelligent diagnostics With its unique imonitor predictive diagnostics functionality, based on METTLER TOLEDO s ISM technology, the M800 tells you not only what is wrong with a sensor but how to fix it before an issue arises. Multi-parameter and multi-channel The M800 s multi-parameter abilities give you greater flexibility, less complexity, and less training and inventory. Two- and four-channel models provide multiple measurements from a single unit. Color touchscreen The color touchscreen provides simple, convenient operation. Just touch and follow the intuitive user interface. 10 METTLER TOLEDO Power News 18

11 M800 multi-parameter, multi-channel transmitter METTLER TOLEDO Power News 18 11

12 Get in-line with METTLER TOLEDO New Water Calculator App for Mobile Devices A new water calculator application for smart phones and mobile devices enables water specialists to perform water calculations and unit conversions using an iphone, ipod touch, ipad, or Android -compatible smart phone or mobile device. This FREE application calculates: j Conductivity, resistivity and total dissolved solids (TDS) conversions j Flow and flow velocities for various pipe sizes j Temperature versus resistivity and conductivity of ultrapure water j Sample and process flow rate unit conversions j Temperature conversion between C and F For more information, visit: c c Mettler-Toledo Thornton, Inc. 36 Middlesex Turnpike Bedford, MA 01730, USA Tel: Fax: Toll Free: PURE mtprous@mt.com Mettler-Toledo AG Process Analytics Im Hackacker 15 CH-8902 Urdorf Switzerland Visit for more information