5 Reasons Why Oil & Gas Operators Might Hesitate To Deploy Technology That Reduces Flaring and Venting

Our Industry is under serious pressure to extinguish well site flares and reduce emissions from both flaring and venting.  Importantly, we’re also busy repairing our balance sheets after several years of low oil and natural gas prices.

If the cost to eliminate routine flaring (allowing occasional flaring for safety if something goes awry at the well site) would make the overall operation unprofitable or require an onerous capital investment, one might understand why it hasn’t been done sooner.

However, systems that eliminate almost all routine flaring and venting by capturing, treating, and selling the gas are both technically proven and commercially beneficial^[1].

The up-front cost is modest, they are straightforward to integrate into existing well site infrastructure, and sale of the recovered gas – which is often rich in natural gas liquids – results in a short pay-back time and significant positive cash flow in the long term.

So, why are operators so hesitant to deploy these solutions?

Here are five of the most common reasons and why they’re misguided.

1. Vapor Recovery Towers Already Capture Most of the Gas 

Vapor is generated at a well site from both the oil stream and the water stream, as the respective storage tanks are loaded and unloaded and as the ambient temperature changes.

On average, Vapor Recovery Towers (VRTs) only capture about 60-80% of the oil stream vapor (unfortunately, most operators don’t measure flared gas volumes, so the actual effectiveness of VRTs is not reported).

That’s not really “most of the gas” in our book.

VRTs are challenging to operate efficiently due to fluctuations in well performance and changes in ambient temperature.

Capturing, treating, and selling that additional 20-40% of the oil stream vapor, as well as any gas coming out of solution from the water stream, is both environmentally responsible and financially lucrative.

2. The Technology is New and Unproven

New is another vague word, frequently used to obfuscate other reasons for avoiding deploying a technology.

Here at EcoVapor, we have been successfully recovering the entire vapor stream at oil and gas sites for over a decade and have completed over 200 installations.

Companies of all sizes – from supermajors to small independents – have deployed the technology in nearly every operating basin across the United States.

When is a new thing not new anymore?  And what does it take to say it’s proven?

Every company will define the burden of proof a little differently, but we think it’s safe to say that time has expired on calling these systems new or unproven.

3. We Don’t Have Oxygen in Our Tank Batteries

The laws of physics make it almost impossible to keep oxygen out of a storage tank operating at or close to atmospheric pressure.

There’s so much oxygen in the atmosphere (around 200,000 ppm) that keeping the concentration of oxygen in the head space gas of a storage tank below the pipeline limit (typically 10 ppm) is a tall task indeed.

It gets even harder when the tank ‘breathes’ due to the ambient temperature variation between a sunny midday and a starry midnight.

That oxygen ingress isn’t an issue when the gas from the tank battery is routed to a low-pressure flare or combustor.  In that case, it helps the gas to burn cleanly.

But when the gas is captured and compressed for export, even a low level of oxygen contamination can breach the pipeline contamination limit and result in either unplanned flaring or production curtailment.

Finally, unless tank vapor is being routinely monitored and analyzed – which is certainly not the case at most well sites we’ve visited – it’s impossible to know how much oxygen is present at any given time and whether the gas would meet pipeline specifications.

The solution is to capture and treat all the gas, regardless of how much oxygen is present.  This is readily accomplished, with oxygen removal systems able to handle up to 50,000 ppm of oxygen (or about 25% air in the total gas stream).

4. Gas Blanketing Ensures that I Can Sell the Tank Vapor

Gas blanketing is the process of routing produced gas into the head space of oil and water storage tanks to slightly increase their operating pressure and keep out any oxygen.

Unfortunately, there are many avenues by which oxygen can enter a low-pressure system, including thief hatches, faulty seals, worn gaskets, vapor shrinkage at night (opening the vacuum relief valve), suction inlets of compressors, and more.

And, importantly, holding a higher pressure in the tanks increases the probability of venting produced gas if the pressure rises faster than the gas blanketing control system can react – for example, due to a surge of liquid into the tank when a separator dump valve opens or a significant variation in well performance.

Gas blanketing might be a low-cost way of keeping most of the oxygen out, but it doesn’t ensure an oxygen-free environment – or even that the oxygen contamination level will meet pipeline specs – and the risk of increased venting makes it an undesirable approach.

Once again, capturing and treating all the gas, regardless of how much oxygen sneaks in, is a more reliable solution that eliminates the risk of both flaring and venting.

5. Production Declines So Quickly that Treating System Capacity will be Oversized Within Months

This is a legitimate concern.  Sizing production equipment for a well site where the production rate will decline 50% or more within a year can be very challenging.

The same is true when sizing separators, vapor recovery towers, and other elements of the production infrastructure.

To mitigate this issue, EcoVapor has developed different sized units to handle common ranges of vapor flow.  Furthermore, we usually lease the equipment to the operator, which means it can be replaced with a smaller capacity unit whenever declining production approaches the turndown limit of the installed system.

Thus operators are not stuck with expensive, oversized equipment but can instead right-size their gas treating capacity – and correspondingly, the treating cost – throughout the life of the well site.

 

Can you think of any other reasons for delaying the installation of commercially viable technology that eliminates routine flaring and venting?

If you can, please give us a call so we can discuss a way to solve it!

 

[1] EcoVapor’s ZerO₂ technology provides a significant reduction in flaring and emissions by capturing the entire vapor stream from a well site and removing oxygen contamination that would otherwise prevent it from being compressed and fed into the sales gas line.  Furthermore, ZerO₂ improves operating cash flow compared to a traditional vapor recovery tower (VRT) by a factor of 2 or more.