Pall Filters Help Recover Lost Megawatts and Lost Revenue
Product: Ultipleat® High Flow Filters
Challenges
A major Midwestern power plant was experiencing significant losses in power generation capacity. The deposition of copper onto the turbine blades was causing an average loss of 27,000 MWh per year. The copper deposition and imbalance of the turbine blades forced the station to decrease the turbine rotation speed. Near the end of a twelve-month fuel cycle, the station derated by 30 MW, resulting in an average of $30,000 per day of lost generation revenue.
As the MW output decreased, the plant had to elevate heat rate (fuel consumption) to maintain a consistent energy output at a lower efficiency. Unable to prevent the copper deposition, the plant started to losing revenue as costs per MW generated increased.
Copper plating on turbines are often removed by mechanical or chemical cleaning. Mechanical cleaning requires complete turbine disassembly, rotor removal, grit blasting the parts, and re-assembly. The process can take up to six weeks and cost more than $350,000 for a 400 MW steam turbine. Chemical cleaning could contaminate the intermediate and low-pressure turbines, heaters and the condenser. Neither method minimizes or eliminates the deposition process from the start.
Industry standards require specific hold points for copper, iron and Silica. Meeting these guidelines is usually the determining factor for start-up duration in plants that adhere to EPRI or similar criteria. In order to prevent a huge financial loss, the station needed to upgrade their existing condensate polisher to reduce copper carry-over.
Solution
Pall Corporation’s proven filtration technology made them an instant fit for the job. With over 40 years of experience helping companies meet their filtration goals, Pall was confident that they could provide an economical solution. After conducting several pilot tests, Pall proposed an assembly of diameter filter housing, which contained nineteen Ultipleat® High Flow filter cartridges. Pall’s Ultipleat High Flow filters have been installed to solve some of the most challenging hydrocarbon contamination issues in the oil industry. The unique structure and flow path of the element makes for the perfect combination of high flux capability and high removal efficiency. The addition of the filter cartages would help to prevent any additional loss of power.
The Ultipleat High Flow filter is the premier alternative to traditional bag and cartridge filter systems that fail to meet critical filtration requirements. Sitting 6-inches in diameter, the Ultipleat High Flow filter element can handle flow rates up to 1,900 lpm (500 gpm). The power is in the filter’s unique crescent-shaped pleated geometry. The crescent filter reduced the required number of elements and housings for high flow applications.
The savings continued for the plant by achieving significantly lower waste disposal costs. The addition of the Ultipleat High Flow filter meant the plant would experience better performance from a system that is two to four times smaller than the former pleated filter that was in place. By reducing the filter size, Pall was able to help slash installation costs.
Minimizing downtime was another a crucial component of maximizing savings for the plant. Solid contaminants were trapped neatly inside the filter for easy removal. The Ultipleat High Flow filter’s patent crescent design would also require up to 30 fewer filter changes. By reducing the filter change frequency, the plant would be able to save up over 40% in filter costs. The savings were a welcome benefit … especially when the plant was initially only looking to prevent the loss in power generation capacity.
Results
Pall was more than up to the challenge when it came to helping the Midwest power plant recover their loss in megawatts. As an innovator in separation science, and an expert in engineering and manufacturing, Pall knew exactly what they were up against. The Ultipleat High Flow technology would prove to be the perfect solution.
Since the installation, the condensate system has undergone five start-ups. The unit has consistently achieved the EPRI start-up guidelines for copper, iron and silica in 15-20 hours. Prior to installation, it took over 35 hours to meet these standards. Furthermore, there have been no power derates due to copper deposition on the turbine blades. The filter installation also reduced risk of boiler tube water wall failures due to under deposit corrosion. By minimizing the copper deposits on turbine blades, and reducing the boiler blow down, the plant could experience economical control of copper, iron and other solids during start-ups.
But the plant has benefitted from far more than protection from corrosion alone. Minimizing downtime meant increased revenue generation from the plant. The Ultipleat High Flow elements combined superior removal efficiency with a lower flow resistance and extended service life. All of which was achieved with a smaller footprint and lower capital costs. Ultimately, installing Pall’s Ultipleat High Flow system provided the plant with a cost-effective solution that reduced start-up time and increase boiler reliability.