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GasTech Engineering is a leading global supplier of gas fired process heaters for the Oil & Gas, Petrochemical and Power Generation Industries.

Modern Environmental Concerns

Comprehensive, cost effective solutions are available to address the environmental implications imposed by the restrictions associated with the Best Available Control Technology (BACT) and Lowest Achievable Emissions Rate (LAER) requirements. BACT limitations often apply to existing sources and consider environmental, energy and economic impacts. LAER limitations reflect the most stringent limitation achievable or the most stringent limitation achieved in practice, whichever is more stringent.

A Non-Attainment Area (NAA) is a designation for a geographical area which fails to meet the standards established by either the National Ambient Air Quality Standard (NAAQS) or pre-emptive local/area standards. Installation of power generation facilities in EPA Non-Attainment Areas must meet the LAER requirements for the applicable criteria pollutants.

Nitrogen Oxides (NOx) and Carbon Monoxide (CO) are products of the combustion process that are often addressed in BACT or LAER requirements. Nitrogen Oxide formation in the combustion process occurs via three (3) mechanisms; thermal NOx, prompt NOx, and NOx attributed to fuel-bound nitrogen. CO formation results from inefficient combustion.

Power Industry Challenge

Internal View of the ultra-low NOx burner, installed in a GasTech Helux Heater

A new power plant was under construction and GasTech provided turbine fuel gas conditioning equipment, including primary separation, pressure regulation, metering, heating and final filtration. Prior to commissioning, the project requirements were modified to include certain environmental restrictions as imposed by LAER.

The original scope included a natural draft water-bath heater for heating natural gas and providing a 50oF superheat upstream of the combustion turbines. As construction of the original heater was complete, GasTech was asked to provide a solution that would minimize the incremental costs to implement the new LAER restrictions.

Comprehensive Solutions

A system was designed utilizing a GasTech Helux Heater with a heat medium circulation system. The heat exchanger section from the original system was salvaged to reduce additional cost.

Heat medium circulation system; 2(100%) pumps, gas/water heat exchanger and expansion tank above

The unique design of the Helux heater stabilizes the flame temperature, which greatly reduces the thermal NOx formation. The Helux heater also thoroughly mixes the combustion air and fuel gas prior to combustion, thus reducing the prompt NOx formation. Also specific to the Helux heater design is the ability to maintain the emission ratio across a wide range of flowing conditions.

The client was able to achieve LAER requirements for the equipment supplied by GasTech. Additionally, LAER requirements for the aggregate power plant installation were attained.

Included in the solution package for the client:

Nema 4x control panel for operation in Class 1, Div. 2, Grp D area classification

• A guaranteed noise level of less than 85 dBA at 3 feet from the equipment
• OSHA approved ladders and operating/maintenance platforms for access to all equipment and instruments
• Fuel gas pressure reduction regulation
• A glycol/water circulation system; including an ASME code expansion tank, two (2) ductile iron wetted end circulation pumps; complete with electric motor drivers and motor starters
• One (1) glycol/water to natural gas heat exchanger
• NEMA 4x, Z-purged, forced draft burner management panel for operation in a Class I, Division 2, Group D area classification. The control cabinet was supplied complete with flame relay for burner management sequencing, temperature controllers (with remote set) for heat media and process temperature control, a PLC for alarm annunciation of the heater and filter separator, and Ethernet communication for client DCS interface capability
• One (1) filter separator capable of removing 100% of liquid/solid particulate >10 microns

GasTech can provide on-site service for commissioning and start-up, as well as training for the operators, for an entire fuel gas conditioning package. Service personnel for operator assistance can be contacted 24 hours a day. GasTech also supplies all spare parts that may be required throughout the life of the equipment.

Final filter separator for turbine protection.