6,000th Site Cleaned
Up By OERB

Started in 1993, part of the Oklahoma Energy Resources Board's (OERB) mission is to cleanup abandoned oilfield sites. Mike Terry, executive director, recently reported that OERB has completed cleaning it's 6,000th site—a site in Oklahoma City that involved removal of concrete remnants of the old Oklahoma City Oil Field. In 2005 alone OERB plans to cleanup 1,200 sites which are selected by the Oklahoma Corporation Commission. OERB's cleanup costs are extremely low, averaging just $4,000 per site. This is a testament to OERB's efficiency and cost control efforts.

Excerpted from Tulsa World, June 3, 2005.

10 Steps to Explosives Safety in The Oilpatch

Field activity is up and experience level is down - a combination that can be dangerous. Whether its old hat or new to you, reviewing explosives safety doesn't take long and it makes sense. The 10 points highlighted in this article are:

1. Have a tailgate safety meeting
2. Check for stray voltage
3. Ground everything
4. Check firing circuit
5. "Safe" and secure the firing circuit/area
6. Arming safety
7. Power-up below 200 ft minimum
8. Secure power at 200 ft minimum
9. Assume a misfire
10. Clean up and inventory

Excerpted from "Ten Steps to Explosive Safety in the Oil Patch," Well Servicing, March/April 2005, pp. 53-54.

Vapor Recovery, Capturing High Value Gas

Gas escaping from storage tanks is high value, usually averaging 2,500

BTU content. The volume of escaping gas depends on the oil volume cycling through the tanks, crude oil composition, separator operating pressure dumping to the tank, the tank configuration and seasonal daily temperatures. Sustained higher natural gas prices (with a 2.5 BTU multiplier) and technological advancements in vapor recovery units (VRUs) justify a producer taking a relook at VRUs. Two field examples described in the article confirm the economic potential of doing so.

• New Mexico: Two VRUs installed on two stock tank batteries, each emitting 90 Mcfd of 2,500 BTU gas into 45-psi sales line. Capital cost (excludes installation and operating costs) was recovered in 21 days (@ $5/million BTU for 2,500 BTU gas).
• North Texas: One VRU installed on stock tank battery emitting 190 Mcfd of 2,400 BTU gas into 50-psi sales line. Capital cost was recovered in 14 days.

A calculator/ economics tool on EPA's Natural Gas STAR program’s website (www.ergweb.com/gasstar/
analytical_tool/vaporrecovery.asp) can be an effective screening tool. For attractive opportunities, further interaction with VRU vendors is recommended.

VRUs are not a commodity item. While straightforward in concept, vapor recovery is challenging—pressures are minute and one is compressing a very wet gas stream. Compressor selection is critical. With wet gas, either rotary screw or rotary vane compressors are appropriate—reciprocating compressors do not do well. Unit packaging/integrated design helps avoid common installation errors.

With vapor recovery one or more tanks are manifolded to a common suction line and piped to the suction scrubber. An "independent" sensing line should be run from the most active or

farthest tank to the sensing unit on the VRU. VRUs are configured to stop and start automatically, depending on tank pressure. Proper design includes a bypass system that will automatically divert discharge volume back to the suction scrubber.

Properly designed units shut down before any vacuum (pulls air/oxygen in, can implode tanks) is reached. If oxygen is entering the system, it is typically caused by an improperly designed package (no bypass system or improper pressure settings), improperly sealed tank hatches or leaking relief valves. Gas blanketing systems help alleviate other issues related to oxygen ingress. In the past, pilot valves were used as pressure sensors but they had operational problems. Newer electronic transmitters operate much more reliably at extremely low pressures.

Other technological advances contributing to improved reliability include variable speed drives on electric-driven compressors, more sophisticated control systems, enhanced lubrication systems, and remote monitoring.

Excerpted from "Producers Tap Vapor Recovery For High-Btu Gas, Additional Revenue Streams," American Oil and Gas Reporter, March 2005, pp. 81-87. Note: A June workshop in Texas by PTTC, EPA STAR, Hy-Bon Engineering and TCEQ had a vapor recovery focus. Contact Sigrid Clift with the PTTC Texas Region about getting a copy of the workshop notebook at a nominal cost (sigrid.clift@
beg.utexas.edu).

International Petroleum Environmental Conference

November 8-11, 2005
Houston, TX

http://ipec.utulsa.edu/
conferences.htm

Work Experience on Rig When Injured

Job Position Experience When Injured