Do Vapor Recovery Units cost money or save money?
I had a great time at Siemens Oil " Gas Innovations Symposium last month. It was a terrific event that focused on trending topics that have been on the industry’s mind for some time. One of the topics, in particular, that I had wanted to discuss further was vapor recovery units (VRUs) and the new regulations surrounding it.
EPA regulations are becoming more stringent as the government strives to reduce volatile organic compounds (VOC). VRUs will soon be leading the initiative in the oil and gas market. Due to recently passed state and federal regulations, I anticipate that over 50,000 VRUs will be installed in this new effort to reduce VOCs by 95 percent by January 2016.
What are VRUs?
VRUs capture light hydrocarbons and other VOCs that escape and collect in the space between the liquid and fixed roof of the storage tank. The full operation of a VRU is controlled through a PLC using a smart pressure transmitter as the main control device. Though there are many variations of VRUs, the main operation components consist of: a suction scrubber, a transfer pump, rotary compressors, a control pilot, check and bypass valves, and a gas sales meter.
Why are VRUs necessary?
Take a look at the picture above. On the left, you see a tank with a pipe above to capture all of the emissions that occur. On the right, you see a thermal photograph of the same tank. Here, you see the emissions that are actually escaping. In addition to the inventory that you are losing, consider that you may have colleagues up there taking manual measurements exposing themselves to VOC emissions.
Although VRUs aren’t exactly a new commodity to the oil and gas market, they certainly aren’t well-liked. Viewed as expensive and time-consuming to install, or involved enough to impact the fast-paced environment of the oil and gas market, the installation of VRUs are believed to act as more of a hindrance than a benefit. Contrary to public belief, VRUs can actually save you money rather than the opposite. Since typical storage tank batteries vent $15,000-$50,000 per month, VRUs can save that amount in a matter of three to 37 months by recovering high volumes of natural gas.
In addition, not only can VRUs reduce VOC emissions by 95% or more, but they can also make it safer for operators and field employees to work on top of the tanks without getting exposed to H2S exposure or explosions.
How to prepare yourself for inspection:
If your oil well produces less than six tons of crude per year, you will not be affected by the newly-passed regulations. But, for wells that produce more than six tons of crude per year, safety inspectors will be visiting each site to evaluate its leakage points, determine how much gas is produced, and how much gas is emitted into the atmosphere. After determining how much vapor is escaping, the inspectors will then recommend which VRU size your operation will require.
Remember, when installing your VRUs, you want to seal the hatches and other leakage points. In doing so, this helps to store the VOC emissions in the storage tank vessel and have them go through the VRU.
To find out how your existing instrumentation can assist the installation of your VRUs, please click here.
To learn more about VRUs, check out this case study.
To learn more about readying your well for government compliance, please click here.
Also, if you’re attending next week’s DUG East Conference in Pittsburgh, PA, stop by our booth #367 to chat! We’d be happy to discuss what challenges you with VRUs and what sort of alternatives you can add into your process.