There certainly are many challenges associated with maintaining an aging power plant’s water chemistry program and ensuring the safety and reliability of plant assets and operators through timely, accurate analysis of water and steam. The program will need to manage and conquer corrosion and scaling issues, standardize methods of sampling water and steam for analysis, and ensure compliance with EPA regulations for waste water disposal.
Older power plants have seen many changes since they were built. New regulations and requirements have been implemented that must be met. Plus, along with an aging building and the continual pressures to increase efficiency and profitability, many traditional plants are losing valuable technical resources as key staff retire. As this happens, they take with them all the knowledge of the water chemistry program that they’ve developed over the years, leaving the plant with limited experience and a lack of dedicated resources to meet its water chemistry needs.
Corrosion & scaling issues
An example of the damage that can occur with improper chemistry is corrosion and scaling. System components can experience corrosion and scaling due to constant contact of water and steam with their metal surfaces. Corrosion, often influenced by pH and temperature, is most prevalent at directional changes and flow disturbances, such as feedwater and economizer elbows, valve perturbations and feedwater heater drains. Pipe walls gradually thin, and catastrophic failures can occur when the corroded area no longer can withstand the pressures. Another area ripe for corrosion is anywhere that water and steam exist simultaneously, such as distribution headers and cooling circuits of air-cooled condensers. Two-phase condensate can be quite damaging in these susceptible locations, and this type of corrosion is not easy to control, so regular inspections are important. Boilers and steam generators are two other areas to watch. Carryover products that can cause issues in steam systems include sodium phosphates, chlorides, sulfates, silica and copper. The allowable concentration of impurities varies from unit to unit and is dependent upon operating pressure, system configuration and other factors, so proper monitoring of and corrective action for each unit is necessary.
An efficient water chemistry program can help prevent and manage corrosion and scaling issues while keeping the system in balance to ensure its integrity, maintaining operational safety and efficiency, and minimizing plant downtime.
Sampling methods
As part of a water chemistry program, a solution for taking standardized and repeatable samples and analyzing them – a Steam and Water Analysis System (SWAS) – needs to be in place. With an appropriate sampling system, samples are extracted from the water and steam circuit and conditioned through cooling, pressure and flow reduction so they can be analyzed for various parameters such as pH, dissolved oxygen, silicate, sodium and cationic or differential conductivity. Reliable sampling and analysis are key in supporting a plant’s compliance with EPA and other regulations while protecting both plant assets and personnel.
Water chemistry services
Plants struggling to keep up with the daily demands of operation may find it difficult to ensure their systems are as safe, efficient and reliable as they need to be. However, you now have options – outsourcing. A partner that can help you accomplish your water and steam chemistry goals is AquatiPro™ Water Chemistry Services. The AquatiPro team brings industry-focused expertise to provide the service, maintenance and training required to meet day-to-day and long-term water chemistry program needs. The continually expanding, factory authorized AquatiPro program provides complete service from conditioning through analytics, regardless of system configuration, condition or manufacturer. By partnering with leading brands of water and steam sampling, conditioning and chemical analysis systems, AquatiPro technicians can provide expertise in the entire water chemistry workflow – from water intake and steam cycling to final waste water disposal. In fact, AquatiPro Water Chemistry Services is the only provider offering certified water chemistry services using a multi-vendor approach.
From a single source, you would be able to obtain steam and water sample conditioning and chemical analysis instrumentation to:
- Guarantee the accuracy of your analyzers and ensure your instrumentation performs on a consistent basis
- Minimize plant downtime and eliminate the possibility of undetected issues
- Increase plant-wide safety
- Improve accuracy and performance
- Increase productivity
- Simplify ordering
The efficiencies of the AquatiPro multi-vendor approach can strengthen your water chemistry program and change how a plant ensures the successful monitoring, alarming and deployment of its water chemistry program. Learn more about AquatiPro Water Chemistry Services here.
This article was originally published on our website.