How is flare stack height calculated?
All Answers (2)
- Flare stack height.
- D =(τE Q/4ᴨK)0.5
- τ = 0.79(100/r)1/16 (100/R)1/16
- Vs =(1720kTZ/S)1/2
- V =(60 Qg T Z)/di2 PCL
- PCL = (2.02)Qg/di2 X {(TS/k(k+1)}1/2
- Milton Beychok fitted the data points from API STD 521 in his book “fundamentals of stack gas dispersion”.
- hfv = 0.0042*Q^0.478.
What are the components of a flare?
The elements of an elevated steam-assisted flare generally consist of gas transport piping (also referred to as flare header or gas collection header), utilities (fuel, steam, and air), piping from the base up, knock-out drum, liquid seal, flare stack, gas seal, burner tip, pilot burners, steam jets, ignition system.
How do steam assisted flares work?
Steam is used at the flare to aspirate air into the combustion zone, shape the flame of the flare, cool the tip of the flare and reduce noise. While steam can be fed to three parts of the flare (center steam, upper rim and inside tubes), they are typically regulated through a single control valve.
How do you calculate stack diameter?
The stack diameter is 2.06 ft (63 m) based on a 3000 fpm (15.3 m/s) exit velocity and a 10,000 cfm (4.7 m 3/s) flow rate. Using a 15 mph (24 k/h), 1320 fpm (6.7 m/s) 1%-wind speed, the added stack height = 3 * 2.06 * 3000/1320 = 14 ft (4.3 m).
How do you calculate the length of a flame?
As the fuel concentration at the top of the flame measured was analysed as some figure like 0.1Ci, the flame length L can be calculated by putting C/Ci=0.1 and x=L in equation 2.
What is velocity seal in flare?
Velocity seals work bases on the premise that when air infiltrates the flare tip, it tends to hug the inner walls of the flare tip. As indicated in the figure-2, a velocity seal is a cone-shaped obstruction placed inside the flare tip so as to obstruct the infiltrating air from ‘hugging the inner wall’.
What is an assisted flare?
Gas-assisted flares are comprised of two risers (waste gas and assist gas) and an assist gas distribution ring at the tip that provides turbulence with combustion air and waste gas at the flare tip. Upon mixing, the increased turbulence in the waste gas stream, improves combustion efficiency and smokeless performance.
What is stack calculation?
So what is a “stack-up”? Tolerance stack-up calculations represent the cumulative effect of part tolerance with respect to an assembly requirement. The idea of tolerances “stacking up” would refer to adding tolerances to find total part tolerance, then comparing that to the available gap or performance limits in order.
What determines the height of a flame?
The flame height depends on the amount of air entrained which, in turn, is proportional to the fuel heat release rate. On occasions, it may also be necessary to calculate the flame projections against a wall from the spill of flammable liquid in a trench or flames emerging from a burning electrical cabinet.
What is the flame height?
Flame height is the average height of flames as measured vertically, up and down. It may be less than flame length if the flames are angled in the horizontal direction, backward or forward.
What is purge rate?
1 tr to rid (something) of (impure or undesirable elements) 2 tr to rid (a state, political party, etc.) of (dissident or troublesome people)
What is molecular seal in flare?
The Molecular Seal is located just below the flare tip and has been designed to prevent air ingress to the flare riser thus preventing the formation of an explosive mixture in the system.
Is the steam supplied to a flare properly designed?
Just as the process piping and controls for a flare need to be properly designed to handle the full range of product flow rates to the flare, the steam supplied to the flare needs equal consideration. Flares are a common site in petrochemical plants.
What are steam-assisted flare solutions?
Our steam-assisted flare solutions use advanced, simplified steam delivery and special noise control technologies to maximize smokeless performance efficiencies and reduce the impact of flaring. Our state-of-the-art Steamizer® XP™ minimizes smoke and reduces steam consumption compared to traditional steam flare solutions.
What is the turndown ratio of a steam-assisted flare?
For the steam-assisted flares that were tested, the turndown ratio ranged from 504.1 to 13.8 (or 0.20 to 7.24 percent utilization); and tip velocities were less than 10 feet per second with center steam excluded.
How do you calculate the flammability of a flare?
The calculation uses the weighted average of the LFLs of the individual compounds (combustible and inert) weighted by their volume percent of the flare vent gas plus center steam. All inerts, including nitrogen, are assumed to have an infinite lower flammability limit (e.g., LFLN2 = ∞).