Combined Cycle Power Plant Dirty Fuel Combustor Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of gas turbine engines with dirty fuels like coal in combined cycle power plants leads to contamination and thermal damage due to particulates blocking film cooling holes and causing corrosion, reducing efficiency.
Innovation Solution
A second combustor is introduced to burn dirty fuels, with turbine exhaust from the gas turbine engine being mixed with the hot gas stream from this combustor, then passed through a heat recovery steam generator to produce steam for a steam turbine, enhancing efficiency and preventing combustion gases from entering the gas turbine engine.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If dirty fuel is burned in the gas turbine engine combustor, then fuel versatility is improved, but turbine reliability deteriorates due to particulate contamination and thermal damage
Solution Approach 1:
The combustor system is divided into two separate combustors: a first combustor that burns clean fuel and a second combustor that burns dirty fuel. This segmentation allows each combustor to be optimized for its specific fuel type, enabling the use of versatile fuels while protecting the turbine from contamination by confining dirty fuel combustion to a dedicated chamber.
Solution Approach 2:
A mixing manifold acts as an intermediary between the two combustors and the turbine. It combines the clean exhaust from the first combustor with the dirty fuel exhaust from the second combustor before delivering the mixed stream to the turbine, thereby diluting contaminants and reducing thermal damage while maintaining the ability to burn dirty fuel.
2Adaptability or versatility
If dirty fuel is burned in the gas turbine engine combustor, then fuel versatility is improved, but manufacturing cost increases due to additional corrosion protection measures
Solution Approach 1:
By segmenting the combustor system into clean and dirty fuel combustors, the design isolates corrosion-prone areas to only the second combustor and its associated exhaust path. This localized approach reduces the overall manufacturing cost compared to protecting the entire turbine system, as corrosion-resistant materials and protective measures are only required where dirty fuel combustion occurs.
3Use of energy by moving object
If turbine exhaust is used to pre-heat inlet air in a heat exchanger, then energy efficiency is improved, but system complexity increases when integrating with steam generation
Solution Approach 1:
The heat recovery system merges two functions into a single integrated heat exchanger: pre-heating the compressor inlet air and generating steam for the steam turbine. This combination improves energy efficiency by maximizing heat recovery from the exhaust stream while avoiding the complexity of separate air pre-heater and steam generator systems.
Solution Approach 2:
The heat exchanger is designed with multi-functionality, serving both as an air pre-heater for the gas turbine cycle and as a steam generator for the steam turbine cycle. This universal component handles multiple thermal recovery tasks simultaneously, improving overall energy utilization without proportionally increasing system complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration allows for the utilization of dirty fuels while maintaining gas turbine engine efficiency, reducing contamination risks and increasing overall power plant efficiency by using the dirty fuel combustor to enhance steam production.
Implementation Method 1
a heat recovery steam generator (HRSG) 20 that converts water into steam using the heat from the turbine exhaust 15
Implementation Method 2
The steam generated is supplied to a steam turbine 21 that is connected to a second generator 22 to produce electrical power
Implementation Method 3
a second combustor 17 that can burn a dirty fuel which is considered a fuel that is not good for burning within the gas turbine engine
Data Source
AI summary
A combined cycle power plant with a gas turbine engine integrated with a dirty fuel combustor in the turbine exhaust and the hot gas stream from the dirty combustor is mixed together and then passed through a heat recovery steam generator to produce steam, the steam being passed through a steam turbine to drive a second electric generator. Some of the turbine exhaust is passed directly into the HRSG while the remaining turbine exhaust is passed into the combustor and burned with the dirty fuel.