Air Dispersion Study for LP Flare Upgrade in Northern Oman

Overview of the Far West New Flare Project

Located in Northern Oman, the Far West New Flare Project aims to upgrade operational efficiency by replacing an existing low-pressure flare with a state-of-the-art system. The new flare is designed to handle a significantly increased gas capacity of 41 million standard cubic feet per day (MMSCFD), compared to the previous system’s capacity of 36 MMSCFD. This upgrade addresses key operational challenges, including instrument air failures and emergency shutdowns, while ensuring improved management of combustion emissions.

To comply with Oman’s environmental regulations, the project included a comprehensive Air Dispersion Study utilizing advanced dispersion modeling software. This study assessed the impact of the upgraded flare system on ambient air quality and ensured adherence to Oman Ministerial Decision MD 41/2017.

Objectives of the Air Dispersion Study

The primary goal of the Air Dispersion Study was to:

• Evaluate Ground-Level Concentrations (GLCs) of pollutants emitted by the LP flare.
• Ensure compliance with Oman’s Ambient Air Quality Standards as outlined in MD 41/2017.
• Analyze the dispersion and potential environmental impact of key pollutants, including Non-Methane Hydrocarbons (NMHC), Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), Carbon Monoxide (CO), and particulate matter (PM2.5).

Methodology

The Air Dispersion Study employed a systematic approach using advanced modeling techniques:

1. Meteorological Data Collection: Meteorological data were sourced from Ibri, Oman’s nearest weather station, to incorporate local atmospheric conditions such as wind patterns, temperature, and humidity.
2. Dispersion Modeling: State-of-the-art simulation software was utilized to predict pollutant dispersion based on emission rates, meteorological inputs, and local topography. The model accounted for atmospheric turbulence, mixing height, and other critical factors influencing dispersion.
3. Scenario Assessment: Various operational scenarios were analyzed, with timeframes including 1-hour, 3-hour, 8-hour, and 24-hour averages, to ensure a comprehensive evaluation of emissions under different conditions.
4. Compliance Evaluation: Predicted GLCs were compared with the threshold limits defined by MD 41/2017 to assess regulatory compliance.

Key Findings

The Air Dispersion Study revealed that the maximum predicted GLCs for all assessed pollutants were well within the permissible limits set by Oman’s MD 41/2017 regulations. Key findings include:

• Non-Methane Hydrocarbons (NMHC): Levels remained below the specified threshold.
• Sulfur Dioxide (SO2): Dispersion was minimal, with concentrations within safe limits.
• Nitrogen Dioxide (NO2): Predicted values did not exceed regulatory standards.
• Carbon Monoxide (CO): Emissions were effectively managed, ensuring compliance.
• Particulate Matter (PM2.5): GLCs adhered to prescribed limits, safeguarding public health.

Conclusion

The Air Dispersion Study for the Far West New Flare Project underscores the importance of predictive modeling in environmental assessments. By leveraging advanced simulation tools, the study ensured that the upgraded flare system met Oman’s stringent air quality standards. Key outcomes include:

• Enhanced operational efficiency with a modernized flare system.
• Compliance with environmental regulations, fostering sustainable industrial practices.
• A framework for proactive air quality management, contributing to long-term environmental sustainability in Oman.

This project highlights the role of innovative engineering solutions in balancing productivity and environmental stewardship. With effective environmental management practices in place, the Far West New Flare Project sets a benchmark for sustainable industrial development in Oman.