NOx, or nitrogen oxides, is a term used to describe a family of seven chemical compounds made up of various combinations of nitrogen and oxygen that contribute heavily to air pollution. Some of these compounds are air pollutants in and of themselves, while others cause pollution when they react with water, temperature, or other elements to produce atmospheric contaminants. While the Environmental Protection Agency (EPA) began regulating emissions in 1963 with the passage of The Clean Air Act (CAA), state and federal agencies continue to expand these regulations as global warming becomes an increasingly imminent concern. Recently, New York tightened its restrictions on the production of NOx by limiting the emissions of simple cycle and regenerative combustion turbines.

The Regulation of NOx Emissions in New York

In May 2019, the State of New York added Part 227-3 to the New York Codes, Rules and Regulations (NYCRR) of the New York Department of State in an effort to reduce NOx emissions. The six-part law, titled “Ozone Season Oxides of Nitrogen (NOx) Emission Limits for Simple Cycle and Regenerative Combustion Turbines,” aims to protect the health of New York residents in keeping with the state’s progressive clean energy goals.

The legislation applies specifically to simple cycle and regenerative combustion turbines larger than 15 MW installed before 1986 in peaking power plants, which run during “peak” times when the demand for energy is higher than usual. It is expected that the retiring of these units will contribute to a combined loss of 3,400 MW, which the New York State Department of Environmental Conservation (DEC) states is less energy than cleaner sources are able to produce. Many units, they say, are over 50 years old and rarely used, but when they are, they emit at least 30 times more NOx emissions than modern turbines.

By May 1, 2023, units will be limited to NOx emissions of up to 100 parts per million (ppm). Additionally, by May 1, 2025, NOx emissions will be limited to 25 ppm for units burning gaseous fuels and 42 ppm for units burning distillate and other liquid fuels.

Petrotech’s Solution to Reduce NOx Emissions

For those required to abide by NOx emissions limits in accordance with New York law, Petrotech’s water injection system provides a solution. By injecting water into the combustor of a heavy-duty gas turbine, peak combustion temperature for a given output is decreased. The advantages of this function include the following:

• NOx Reduction: When used exclusively for NOx reduction, the average ppm is 20-30
• Power Augmentation: When used for power augmentation at the same peak combustion temperature, the water injection system increases power output from 6% to 12%

Petrotech offers the following features of the water injection system as part of our turnkey service solutions:

• Water treatment unit
• Water nozzles
• Water injection pump and flow control unit
• Water to Fuel Ratio injection controller

The skid-mounted display features all measurements, analog outputs, and computed values. Controllers include functions for water/fuel ratio, liquid fuel mass flow, and gas fuel flow (mass and standard).

For over 40 years, Petrotech has been an established leader in the manufacturing and provision of innovative turbomachinery control systems. Our advanced technology and turnkey solutions allow us to provide our global clients with reliable, efficient products and services. To learn more about our water injection system or to request a quote, contact us today.