Leveraging Modern Flow Technologies to Improve Safety in Refineries | AIChE

Leveraging Modern Flow Technologies to Improve Safety in Refineries

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Flares Are the End of the Line; Selecting and Permitting

INTRODUCTION

Flare is one of the key equipment in any refinery or LNG facility. Many relief valves relieve to flare, and if the flare is not permitted corrected – and functional - the plant is down. You cannot operate the plant without an active flare or flare field. The permitting of a flare is one of the prime activities in the permitting process. But the permit is dependent on the type of flare. This presentation covers various Federal Regulations involved in the permitting process, whether general or specific to each type of flare.

FLARE TYPES AND THEIR DESIGN FUCTURES

There are mainly three types of flares. The most common and most economical one is an elevated flare. There are elevated flares as high as 660 ft. The can be classified many ways; self-supported, guy wire supported, derrick supported, demountable type etc. One of the most important is the type of burner, whether a pipe tip or “furnace” burners. The second type is a ground flare with rows of furnace burners arranged in arrays at grade and surrounded with a wind fence. The last type is an enclosed flare with furnace burner enclosed with a tall stack. This type can be large as 70 ft in diameter and 150 ft tall. The flare type on a given project is selected based on the plot availability, location of the plant, sparing philosophy etc.

PERMITTING REGULATIONS

This presentation will discuss cover various Federal regulations that are applicable to all types of flares and the various parameter that the regulators are needing when apply for the permit. The presentation will cover the required destruction efficiency of the flaring gases, exit velocity for an elevated flare, alternate means of emission limitation for ground flares. In particular, the tip velocity, burner type, backpressure, emission testing and smokeless capacity are specific to each type of flare.

WHAT YOU WILL LEARN

  • This paper will provide sufficient information to ensure the correct type of flare is selected and permitted
  • This paper will cover various flares types employed in refinery and in LNG plants
  • The limitations of these flare
  • Importance of flare in any facility
  • Application Federal Regulations
  • Parameter required in the permitting applications
  • Ground flare testing to establish minimum destruction efficiency
  • Alternate means of emission limitation requirements in lieu of testing