Multi-Tip Staged Enclosed Ground Flare for Gas Gathering Station Relief Gas

Oil & Gas Client

Assam, India

Multi-tip staged burner and PLC-based staging control engineered for smokeless combustion of gas gathering station relief gas.

7,000

Nm³/hr

100 mbar(g)

Inlet Pressure

API 521/537

Design Std

Multi-tip staged enclosed ground flare being engineered by CRA for Gas Gathering Station, Assam.

The Overview

Oil & Gas Operator

Client

Oil & Gas

Sector

Combustion of gas gathering station relief gas

Application

Under Engineering

Status

7,000 Nm³/hr at 100 mbar(g)

Capacity

Assam, India

Location

CRA is engineering an enclosed ground flare system for Gas Gathering Station in Assam, for the safe, smokeless combustion of associated gas under normal, upset, and emergency conditions. The system centres on a multi-tip staged burner with a stainless steel water seal drum and PLC-based staging control, sized for 7,000 Nm³/hr at 100 mbar(g) inlet pressure. Design and manufacture follow API 521 and API 537, with Zone 2 flameproof instrumentation throughout, the same in-house engineering-to-delivery approach CRA applies across its enclosed flare installations.

The Challenge

Engineering Reliable Relief Gas Combustion Across Normal, Upset, and Emergency Conditions

The Nagajan Gas Gathering Station required an enclosed flare capable of handling associated gas across a wide range of operating states within a single system. Key constraints included:

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Reliable, smokeless combustion across normal, upset, and emergency flow conditions
A wide turndown range from a single flare system rather than separate units per condition
Zone 2 flameproof area classification across all instrumentation
Design and manufacture compliant with API 521 and API 537
Dependable ignition and reignition under field conditions at the gas gathering station

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Our Solution

Multi-Tip Staged Burner with PLC-Based Staging Control

CRA is engineering a fully in-house enclosed ground flare system sized to the station’s full range of relief gas conditions.

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Core Scope Includes:

Multi-tip staged burner sized for 7,000 Nm³/hr at 100 mbar(g) inlet pressure
Stainless steel water seal drum
PLC-based staging control matching burner output to gas flow across all operating states
Dual ignition via a Flame Front Generator and a High Energy Ignition system
Zone 2 flameproof instrumentation throughout

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Engineering Basis

Designed to API 521 and API 537 for Gas Gathering Station Service

The system design follows the same in-house engineering-to-delivery approach CRA applies across its enclosed flare installations:

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Design and manufacture to API 521 and API 537
Staged burner sizing to hold stable, smokeless combustion across normal, upset, and emergency flows
Redundant ignition (FFG and HEI) for dependable relight in the field
Zone 2 flameproof instrumentation specification across the full scope

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Stack height will be finalised once detailed design is complete.

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Conclusion

Applying CRA's In-House Enclosed Flare Approach to Upstream Gas Gathering

This project reflects CRA’s consistent approach to enclosed ground flare design across its upstream oil and gas installations, applying staged burner engineering, redundant ignition, and full API 521/537 compliance to Gas Gathering Station in Assam.

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