NIOSH Flowback Study. William G. Burket, CFPS

Transcription

1 NIOSH Flowback Study William G. Burket, CFPS

2 Objectives of Study Determine exposures of employees during flowback operations. Measure other hazards, such as noise, that are inherent to flowback operations. Study occurred first week of March Two sites were selected-flowback on a dry gas site and on a wet gas site. Study was to include production operations but time did not permit.

3 Completions: Flowback

4 Potential Worker Hazards Combustion Hazards Potential health hazards to hydrocarbons Short-Term Exposures: Dizziness, nausea, fatigue, irregular breathing, irregular heartrate, respiratory irritation, headaches, eye irritation Chronic Exposures: Damage to the nervous system and vital organs Asphyxiation

5 Flowback Workers Flowback workers may be at a greater risk of being exposed to hydrocarbons Multiple service providers have an active role on-site during flowback operations Only one company actually provides the primary flowback services Typically 4-5 employees working 12 hour shifts to provide 24 hour service Flowback workers are responsible for initially Directing and handling the liquids and gases being produced by a well Operating and maintaining all associated equipment

6 Potential Exposure Risks During Flowback Exposures to hydrocarbons may occur during specific job tasks and around specific pieces of equipment Risk factors include Job assignments Location layouts Type of equipment on-site

7 Separators Separators separate Solids, liquids, and gases are initially comingled when they are being produced Typical multi-well separators being used on locations have their controls housed in an enclosed area Protects the equipment and the workers from the elements

8 Flowback Separator Enclosure

9 Separators Hydrocarbons may be present in these enclosures if Equipment controls are operating using site gas Equipment sight glasses are being cleared Time spent inside of these enclosures vary Wells are first beginning to flow through a separator Controls are having difficulties maintaining set points Ambient temperature is cold Additional concerns with separators include Ventilation Noise

10 Flowback Tanks Open-top tanks are utilized to store flowback water during flowback operations Flowback workers are responsible for monitoring and maintaining the fluid levels in these tanks

11 Sampling NIOSH performed LEL, time weighted average (TWA), short term exposure levels (STEL) and grab samples. Samples were specifically analyzed for: Benzene Glutaraldehyde (biocide) Methanol Propargyl alcohol (corrosion inhibitor) Propane and butane Other hydrocarbons C6 to C11 Noise

12 Results

13 Flowback Workers Flowback service providers to reduce hydrocarbon exposures associated with Working inside of an enclosure on a separator Manually gauging flowback tanks Properly operating and maintaining a separator and monitoring tanks are essential tasks These tasks help ensure safe, environmentally sound, and effective flowback operations The jobs themselves cannot be eliminated Focus has been on how contractors perform them

14 Exposure Reduction Efforts: Separators Eliminate operating flowback separators with site gas Separators are required to operate using an air compressor, with having either nitrogen or a 2 nd air compressor as a back-up Work with flowback service providers to plumb vent lines outside of the enclosures when possible Educate flowback workers on hydrocarbons If they understand the hazard, they are more likely to change their behaviors Reduce frequency and duration spent inside of the enclosures Open doors and windows to improve ventilation

15 Exposure Reduction Efforts: Flowback Tanks Remote monitoring systems Worker education Minimum PPE requirements Hard hat Safety glasses Outermost layer is fire retardant (FR) Chemical resistant gloves* Appropriate respirator*

16 Exposure Reduction Efforts: Education Hydrocarbons are not a new hazard Educating workers on the short-term and longterm hazards associated with exposures to hydrocarbons makes them more likely to follow established procedures Wear appropriate PPE Limit time and frequency spent on top of a tank React appropriately when multi-gas meters alarm

17 Worker Education What should be done when CGI goes into alarm. Not turning on CGI. Hearing protection Not using hearing protection in areas clearly marked.

18 Exposure Reduction Efforts: Remote Monitoring Systems The most effective control is to eliminate the exposure Remote monitoring technology is emerging

19 Infrared Cameras

20 Ultra Sonic Level Sensor Non-contact sensors. Sensor emits high frequency acoustic waves. Can detect liquid interfaces. Affected by moisture, temperature and pressure requiring frequent calibration. Accuracy is with 2% of calibration.

21 Guided Wave Radar Intrinsically safe Easily attached, operates at wide range temps. Accuracy within 0.08 inches

22 Questions