Control Solutions During Manual Tank Gauging. Chad Hyman SRP Environmental

Transcription

1 Control Solutions During Manual Tank Gauging Chad Hyman SRP Environmental

2 Objectives Manual Tank Gauging Quantify potential atmospheric hazards without engineering or administrative controls Quantify the risk reduction when utilizing current engineering and administrative controls Correlate data variations based on well product compositions

3 Equipment/Sampling Media MultiRae (NDIR) % Methane, % LEL, Oxygen, CO Breathing zone on chest ToxiRae (WB) % LEL Breathing zone on chest Photoionization Detector (PID) 10.6 ev lamp Midsection of individual Used primarily as a reference when collecting BTEX samples

4 Equipment/Sampling Media Flame Ionization Detector TVA 1000 Evaluate the breathing zone of the individual Grab Sample at Source (1 above hatch) VeriAir Flex (Nextteq) GC analysis for Total VOC Compare to FID BZ sample Charcoal Tube with Pump BTEX & Naphthalene 1 LPM for various range (3 8 minutes)

5 Sampling Method Appointed locations based on risk evaluation Consisted of product composition, natural air movement, & equipment setup Three locations identified by production operators and engineer Monitoring conducted over a two day period Allowed 24 hours between the sampling events to limit the variability within the data collection Time and temperature were correlated to ensure similar conditions Evaporation, headspace composition, system pressure

6 Sampling Method Day 1 No controls in place Samples were collected during initial venting and again when purging the system Day 2 Controls in place Samples were collected during initial venting while following current SOPs and during alterations to the SOP The same instrumentation and sampling media was used for each sampling event

7 Evaluation Method Day 1 Atmospheric testing during the initial opening of the hatch on the production tank Grab sample for VOCs FID PID LEL, Methane, Oxygen

8 Evaluation Method Day 1 Atmospheric testing during plunger run/separator dump (purging) Grab sample for VOCs FID PID LEL, Methane, Oxygen BTEX, Naphthalene (BZ)

9 Analytical Highlights No Controls Initial Total VOC (76,000 ppm) FID (>50,000 ppm) PID (124 ppm) BTEX (not collected) LEL (100%) Methane (~ 5.0%) Oxygen (19.0%) Purging Total VOC (600,000 ppm) FID (>50,000 ppm) PID (308 ppm) BTEX (BZ) (>55 ppm) LEL (100%) Methane (94.80%) Oxygen (9.80%

10 Analytical Highlights No Controls

11 Evaluation Method Day 2 Following SOP (current & altered) Grab sample for VOCs FID PID LEL, Methane, Oxygen BTEX, Naphthalene (BZ)

12 Evaluation Method Day 2 Example of Engineering Controls

13 Evaluation Method Day 2 Example of Engineering Controls

14 Analytical Highlights SOPs BZ 1 Minute Ventilation Opening FID 300 ppm (Opening) LEL 6.0% (Opening) 2 Minute Ventilation Opening FID 400 ppm (Opening) LEL 6.0% (Opening) Gauging Total VOC 4,000 ppm FID 40 ppm LEL 0.0% BTEX <0.1 ppm Gauging Total VOC 0 ppm FID 0.8 ppm LEL 0.0% BTEX <0.1 ppm

15 Analytical Highlights Control Comparison Purging Total VOC (600,000 ppm) FID (>50,000 ppm) PID (308 ppm) BTEX (BZ) (>55 ppm) LEL (100%) Methane (94.80%) Oxygen (9.80%) Isolation w/2 minute vent Total VOC (0 ppm) FID (0.8 ppm) PID (54.6 ppm) BTEX (<0.10 ppm) LEL(0.0%) Methane (0.00%) Oxygen (ambient)

16 Cost Benefit Analysis Control Comparison $3,000,000 $2,803,488 $2,500,000 $2,000,000 $1,500,000 $1,408,767 $1,000,000 $544,286 $1,092,268 $500,000 $300,000 $745,021 $503,969 $0 $31,000 Initial Cost 10 Yr Cost 20 Yr Cost 30 Yr Cost Equipment Implementation PPE Implementation

17 Additional Observations Staging/Utilizing equipment to minimize the hydrocarbon headspace within the production tanks Separator Tower Production Tank Vapor Recovery Unit to draw the headspace* Potential for similar exposures at equipment other than production tanks Gas Process Unit (GPU) Drip Tanks