Application of Lean Premixed Combustion for Emission Control in Different Combustors

Recently, power plants extensively use heavy-duty gas turbines in a very extreme way. There are two problems related to the operation of these gas turbines of heavy-duty for extended time. These two problems are connected to the overabundance of fossil fuels (such coal and natural gas) used in the production of power, in addition to the expansion of environmental protocols and restrictions on flue gas emissions, which include carbon monoxide, carbon dioxide, as well as nitrogen oxides (CO2, CO, and NOx). Researchers have created many combustion approaches, including oxy-fuel combustion with carbon detention and hydrogen-rich fuel burning, in order to meet these limits. Due to its realistic combustor presentation and better flame steadiness features, non-premixed flame type is typically used in gas turbine combustors for power production. Currently, non-premixed flames are the highest cause of NOx releases, making this type of combustors obsolete. The creation of innovative combustors that can adhere to such stringent requirements was necessitated by the advent of more tightly controlled environmental rules. New technologies have recently been created to produce clean energy in gas turbines. These include lean premixed combustion (MPC) and catalytic combustion (CC) (LPM). The safety and durability of catalytic burning are known to be poor, and it is also known to be quite expensive. Although LPM combustion reduces NOx emissions by moderating the combustion temperature, it also causes flame instability and narrower combustor operability ranges. This chapter’s goal is to describe the findings of extensive research on the flow-field, combustion, and stability properties of premixed flames in various burner configurations for a widespread array of industrial applications. Following a discussion of the features of lean premixed combustion for various industrial applications, this topic is the subject of several in-depth investigations. In the first inquiry, a model combustor of a gas-turbine is used to examine the structure and steadiness of swirl-stabilized premixed flame CH4/O2/CO2 both experimentally and numerically. Validated of the LES computational model was conducted using different assessments with experimental data for radial and axial temperature profiles as well as projected OH* concentration maps vs graphical flame presence. In the second study, jet spacing, and diameter are experimentally tested in a burner that resembles a micromixer in order to potentially use them to zero-emission gas turbines. Comparisons are made between different burner geometries with the three different headends known as HE1, HE2, and HE3. The flame-base velocity is held unbroken value of 5.2 m/s. In the O2/CO2 oxidizer, the comparison was done at various equivalence ratio values over a range of oxygen portion (O2 vol.%). The third investigation examines the operation of an H2-enriched compressed natural gas (CNG) burner that is punched over by a flexible fuel/oxidizer combustion chamber housing partially premixed oxy-flame. A variety of parameters for the hydrogen fraction (HF), oxygen fraction (OF), and equivalence ratio (φ) were used in the experiments. In the most recent study, the stable auto-ignition ranges in micro catalytic honeycomb reactor that is platinum-coated for the micro-burning of CH4 and CH4–H2 blends are quantified. Transient and steady models under fictitious auto-thermal circumstances were run to examine the relationship between heat transmission and burning in such a micro burner.