Kazeroon Power Plant Mixing Chamber Refurbishment and Optimization Project: A Report by Paya Materials
Introduction:
Power plants, as one of the main pillars of energy supply in modern societies, play a vital role in development and progress. Among them, gas turbines hold a special position in the power industry due to their high efficiency and fast startup capabilities. The mixing chamber and its related components act as the heart of gas turbines, responsible for the critical task of mixing air and fuel to create optimal conditions for combustion and energy generation. Given the harsh operating conditions these components endure—constantly exposed to high temperatures and mechanical stresses—wear and deterioration are inevitable.
Understanding the importance of this issue and aiming to increase service life, improve performance, and enhance the efficiency of mixing chamber components, Paya Materials successfully completed a refurbishment and optimization project on these components at Kazeroon Power Plant. This comprehensive report details the project from initial steps to final achievements.
The Key Role of Mixing Chamber Components in Gas Turbine Performance
The mixing chamber is the compartment where compressed air from the compressor is mixed with fuel (typically natural gas). This mixing must ensure a homogeneous blend with an accurate air-to-fuel ratio. Such a uniform mixture is essential for complete combustion and maximum energy output. Any defect or malfunction in the mixing chamber can lead to incomplete combustion, reduced efficiency, increased emissions, and even damage to other turbine parts.
Common Issues of Mixing Chambers in Power Plants and Operational Challenges
Mixing chamber components face multiple challenges due to their exposure to extremely harsh operating conditions:
High Temperature:
The temperature of gases entering the mixing chamber can exceed 1000°C. Such high temperatures induce severe thermal stresses in the components.
Mechanical Stresses:
In addition to thermal stresses, mixing chamber parts are subjected to mechanical stresses caused by gas pressure and vibrations.
Corrosion and Oxidation:
The hot gases entering the mixing chamber contain corrosive and oxidizing agents, which can lead to corrosion and oxidation of the components.
Erosion:
The high-velocity gas flow inside the mixing chamber (approximately 300 meters per second) can cause erosion of internal surfaces.
These challenges gradually cause damage such as cracks, corrosion, deformation, and thickness reduction in the mixing chamber parts over time.
Stages of Mixing Chamber Refurbishment and Optimization by Paya Materials
The optimization of a power plant mixing chamber is a multi-stage process that begins with identifying existing problems and ends with implementing engineering solutions. Initially, visual inspection, thickness measurement, crack detection, and metallurgical analysis are conducted. Then, an engineering redesign addresses weak points, and suitable reinforcement materials are selected. Finally, the refurbishment process includes specialized welding, precise machining, and multi-stage quality control. This optimization cycle improves turbine performance and extends the service life of components.
The refurbishment and optimization project of the mixing chamber components at Kazeroon Power Plant was carried out in several key stages utilizing the expertise and technical knowledge of Paya Materials’ engineering team:
Initial Inspection and Precise Fault Diagnosis
- Visual Testing (VT):
At this stage, the parts were thoroughly inspected for cracks, corrosion, deformation, and other visible defects. - Penetrant Testing (PT):
To detect fine surface cracks, penetrant testing was employed. This method uses colored or fluorescent penetrants to reveal surface-breaking defects. - Magnetic Particle Testing (MT):
When applicable, for parts that can be magnetized, magnetic particle testing was used to identify subsurface cracks. - Ultrasonic Testing (UT):
To measure the remaining thickness and detect internal defects, ultrasonic testing was performed. This technique uses high-frequency sound waves to provide detailed insight into the internal structure of components.
Material Analysis and Metallurgical Examinations:
- Sampling:
- Samples were taken from various sections of the components for metallurgical testing.
- Chemical Analysis:
- The chemical composition of the parts was determined using spectroscopic and quantitative analysis methods to ensure compliance with required standards.
- Metallography:
- Microscopic cross-sections of the samples were prepared and examined under a microscope to study the microstructure of the components. This examination provided valuable information about existing phases, grain size, presence of micro-cracks, and other structural defects.
- Mechanical Testing:
- To determine the mechanical properties of the components, tensile tests, hardness measurements, and impact tests were performed. These tests provide data on strength, hardness, toughness, and impact resistance of the parts.
Reconstruction and Optimization Process Design:
Based on the results of inspections and analyses, the engineering team at Paya Materials designed the reconstruction and optimization process for the components. This process included the following steps:
- Selection of Suitable Welding Method:
Considering the material of the components, types of defects, and operating conditions, an appropriate welding method (such as GTAW or TIG) was selected. - Selection of Consumables:
Welding consumables (electrodes or filler materials) were chosen based on the component materials and relevant standards. - Determination of Welding Parameters:
Welding parameters (including current, voltage, speed, shielding gas type, etc.) were adjusted to achieve high-quality welding with minimal residual stresses. - Heat Treatment:
To reduce residual stresses from welding and improve the mechanical properties of the parts, an appropriate heat treatment process (such as annealing or stress relieving) was designed and implemented. - Coating:
If required, protective coatings (such as ceramic or metallic coatings) were applied to enhance the components’ resistance against corrosion, wear, and oxidation.
Implementation of Reconstruction and Optimization:
- Component Preparation:
Before welding, component surfaces were thoroughly cleaned and prepared to remove any contaminants, grease, oxides, or paint. - Welding:
Welding was carried out using the selected method and consumables, strictly adhering to the specified parameters. Skilled and experienced welders at Paya Materials performed this step with high precision. - Heat Treatment:
After welding, components underwent the designed heat treatment to reduce residual stresses and improve mechanical properties. - Coating:
Protective coatings were applied on component surfaces where necessary. - Machining:
After reconstruction, components were machined as needed to achieve the required dimensions and tolerances.
Final Quality Control:
After completing the reconstruction and optimization, components underwent comprehensive inspection and quality control:
- Visual Inspection (VT):
To ensure no visible defects were present. - Penetrant Testing (PT):
To confirm the absence of surface cracks. - Ultrasonic Testing (UT):
To measure remaining thickness and detect internal defects. - Mechanical Testing:
To verify that mechanical properties met the specified requirements.
Increasing Turbine Efficiency and Reducing Operational Costs through Mixing Chamber Reconstruction
The reconstruction and optimization project of the mixing chamber components at Kazeroon Power Plant achieved significant results:
- Increased Component Lifespan:
Reconstruction and optimization substantially extended the components’ service life, reducing maintenance costs and enhancing the plant’s reliability. The designed life of the reconstructed parts increased from 25,000 to 40,000 operating hours. - Improved Turbine Performance and Efficiency:
By correcting defects and optimizing the structure of the components, the thermal efficiency of the power plant increased by approximately 2.8%. This improvement reduced fuel consumption and environmental pollutants. - Reduced Maintenance Costs:
With longer component life and lower failure probability, the plant’s maintenance expenses significantly decreased. Natural gas consumption dropped by about 1.5%, saving approximately 500,000 cubic meters annually. Emergency repair costs and plant downtime were reduced by over 35%. - Prevention of Unplanned Plant Shutdowns:
Reconstruction lowered the likelihood of unexpected shutdowns caused by component failure, thereby improving grid stability and preventing losses due to power outages. - Localization of Technical Knowledge:
This project provided an opportunity to localize technical expertise in power plant component reconstruction and optimization, reducing dependency on foreign companies and saving foreign exchange.
Cost Reduction in Maintenance through Professional Mixing Chamber Reconstruction
Ignoring timely repair of damaged mixing chamber components can lead to very high maintenance costs for power plants. Specialized and preventive reconstruction not only saves costs but also prevents unexpected downtimes and efficiency drops. The Paya Materials team offers economical and technical solutions helping power plants achieve maximum operational stability with minimum expenses.
Paya Materials Services in Gas Turbine Power Plant Mixing Chamber Reconstruction
Paya Materials, as a pioneer in the power plant parts reconstruction industry, offers specialized services in the reconstruction and optimization of mixing chambers. These services include precise defect diagnosis, material analysis, reconstruction process design, selection of heat- and corrosion-resistant alloys, heat treatment, professional welding, machining, and final quality control. Leveraging an experienced engineering team and specialized equipment, Paya Materials has played an effective role in reducing costs and extending component lifetimes.
Conclusion: Impact of Mixing Chamber Reconstruction on Kazeroon Power Plant Performance
The reconstruction and optimization project of the mixing chamber components at Kazeroon Power Plant is a successful example of Paya Materials’ engineering and specialized service capabilities in the power plant sector. Relying on the technical expertise of its specialists and advanced equipment, the company completed the project with the highest quality standards and international compliance. Paya Materials is ready to provide similar services to other power plants and industries across the country.
