NEW DEVELOPMENTS IN FLARING PRESENTED BY

EAST HARRIS COUNTY AIR PARTNERS

Flare Discussion 2

y Types y Regulation y Operation y TCEQ Flare Study y Next Steps y Anticipated Results

What do you know about flares? 3

?

Types of Flares 4

Staged Flare

Single Point Flare

Types of Flares 5

Air-assisted Flares

Types of Flares 6

Multi-point Ground Flare

Types of Flares 7

Enclosed Ground Flare and Tips

Types of Flares 8

Enclosed Ground Flare and Flare Tips (from inside)

Types of Flares 9

Steam-assisted Flares

Types of Flares 10

Elevated Flare

Ground Flares

Flare Operation 11

y Primary function is as a safety device Protect equipment from catastrophic failure (pressure relief) Protect employees/community from exposure to pollutants Designed with safety in mind: big enough to handle the largest release y Over the years, flare operations have evolved Initially designed only for emergencies (safety devices) Then became “dump” for waste gases, off-spec materials, etc. Later used as alternative to venting directly to atmosphere Today used as emissions control devices for most process vents

Flare Operation 12

y In addition to process gases, purge gas and assist gas

are often routed to flares Purge gas (usually natural gas) sweeps the flare header of oxygen, corrosives, reactives, and inerts Assist gases (usually steam or air) improve mixing for better combustion, help protect the flare tip from heat damage, and help minimize visible emissions

Flare Operation 13

y Flare operators have been trained to add sufficient steam

(or air) to prevent visible emissions Over the years this has translated into “more is better”

y Many facilities have reduced continuous flaring, resulting

in flares that operate well below their design capacities Operating at 99% DRE Visible Steam Results in Rapidly Falling DRE

Test Point S4.3

Why is High DRE Important? 23

Test Point S4.2

At 99.2% DRE, 20,000 pounds of flare gas results in (0.008 x 20000) = 160 pounds of unburned flare gas

Test Point S4.7

At 90.6% DRE, 20,000 pounds of flare gas results in (0.094 x 20000) = 1880 pounds of unburned flare gas

Test Point S4.3

At 27.3% DRE, 20,000 pounds of flare gas results in (0.727 x 20000) = 14,540 pounds of unburned flare gas

Third photo has almost 100 times higher emissions compared to first photo

TCEQ Flare Test Results Summary 24

y The flares tested were able to achieve greater than 99% DRE for

vent gas streams at low flow rates (high turndown) under certain conditions

y For the conditions tested, the highest DRE was achieved at or near

the point when smoke first appeared (incipient smoke point)

y Low DRE occurred with invisible flames y Operating the flare within legal requirements of 60.18 and no visible

emissions may or may not minimize emissions

y Proper assist rates appear to be key to good DRE under high

turndown conditions

Flares in your Area 25

y Plant Managers have provided a brief summary of

the number & types of flares they have Emergency-only flares Process-only flares Combination emergency & process flares

Flares in your Area 26

y Summary of DPCAC Flare Survey 7 of 14 DPCAC plants have flares 50 flares among the 7 plants 3 of the 50 flares are emergency only flares 24 of the 50 flares are process only flares, with continuous flow 10 of the 50 flares are process only flares, with intermittent flow 13 of the 50 flares are combination flares 13 of the 50 flares are steam-assisted 5 of the 50 flares are air-assisted 12 of the 50 flares have no assist 1 plant of 7 (Shell) has flare gas recovery

Next Steps 27

y TCEQ, EPA, and Industry are working to better understand flare

performance

y Industry is examining its current flare operating practices to find

improvements

Looking at manual assist rates Exploring better controls, monitoring equipment, and alternative emissions control technology that might be implemented in some cases

y TCEQ is developing flare operator guidance y EPA is developing new flare rules y Flare vendors are reassessing their designs and operating

recommendations

Over-Steamed? 28

Too Little Assist?

“Perfect” Assist? 29

Proper Assist = High DRE 30

Results 31

y Changes to flare operations will potentially result in: New visual landscape of small “candles” Likelihood of seeing some short-duration visible emissions from flares y But also… Reduced emissions ☺ Improved air quality ☺ Better public health ☺