Swan Analytical USA
225 Larkin Dr
Wheeling, IL 60090
Contact: Dominic O'Donnell
The station chemist and operator strive to minimize corrosion, boiler chemical cleaning frequency, and eliminate boiler and HRSG tube failures due to internal corrosion mechanisms such as under deposit corrosion, hydrogen damage, corrosion fatigue, acid phosphate corrosion, and caustic gouging. This requires choosing the appropriate chemical treatment regimen and optimizing the chemical treatment.
Maintaining generator temperature is critical to efficient power plant operation. Utility generators typically employ hydrogen to cool the generator, however many also use high purity water in addition to hydrogen. The Swan AMI Hydrogen analyzer provides a reliable monitor for measuring dissolved hydrogen in stator cooling water. The monitor comes complete with transmitter, flow cell, and sensor all pre-mounted on a durable stainless-steel panel for quick installation and startup.
Monitoring corrosion product transport in steam and water cycles is essential to minimize corrosion. Iron corrosion products exist predominately as undissolved suspended particles therefore to measure the total iron a digestion must be performed. Currently there are no total iron analyzers available to continuously monitor total iron therefore surrogate methods such as nephelometry as well as particle monitors have been employed. This paper describes the results of research employing nephelometry to monitor corrosion product transport.
The conductivity measurement after a cation exchanger in power plants with steam turbines was introduced soon after 1950 by Larson and Lane . As a result of the simple measuring principle, the sensitivity and its high reliability, the conductivity measurement after cation exchanger has become the most commonly used analytical method in power plants with steam generators.
Continuous analyzers are an integral part of the process to maintain quality, ensure compliance, and protect public health. Therefore it is imperative to ensure the analyzers are functioning properly and provide accurate and reliable data. This requires validation of the data provided by the analyzer on a routine basis. In addition some continuous analyzers incorporate internal data validation capabilities to inform the end user the reliability of the data provided by the analyzer. This paper discusses integrated data validation and how they may be integrated into SCADA systems.
Today’s demands require generating units to rapidly respond to changing generation requirements and supply fluctuations from renewables such as solar and wind power. OEM’s have designed combined cycle units that can reach full load in less than 30 minutes without sacrificing efficiency or parts life. To achieve this, the OEM’s have incorporated degassed conductivity as their steam purity conductivity requirement.
This report gives a brief outline of the general measuring methods. Further, it illustrates the possibilities and limitations of the direct UV oxidation, as well as which technical modifications were made to the monitoring instrument, AMI Line TOC, to improve the performance of the UV reactor and, therefore, the precision of the instrument.
When you’re running a steam-generation power plant, the more information you can get about the conductivity process, the better. Details about the startup, condensate, and feedwater systems can help with efficiency and to avoid costly mistakes. In this field, those statistics aren’t just a luxury, they are required reading.
FAC is a corrosion mechanism that increases operating and maintenance costs, impacts unit reliability, and most importantly can be a safety concern. Cycle chemistry must be customized for each unit to address its unique design and operating issues. This requires representative sampling, accurate and reliable continuous monitoring, and meticulous control of the chemistry to minimize and hopefully mitigate FAC. Many factors in today’s environment impact unit operations and chemistry control.
Solution pH is the most important and most difficult parameter measured in the steam/water cycle. There two methods of monitoring pH in this environment, direct measure and calculated pH by differential conductivity.
When I began my career as a power plant chemist most continuous analyzers were trending devices at best. Conductivity was the most reliable analyzer and the temperature compensation algorithms were marginal. Sample conditioning with respect to sample temperature control was not very good as well. By Randy C. Turner, Technical Director, Swan Analytical USA