The Monitor

Production Process Insights

Avoid Pipeline Freeze with a Methanol Injection Plan

Posted by Bryan Stockburger on 10/19/21 8:00 AM

Avoid Pipeline Freeze - Methanol Injection

With winter quickly approaching, frozen pipelines can have a lasting impact on your oil and gas production operations.

As temperatures drop, water and condensation can freeze in pipes, which creates flow blockages and causes system component damage.

The competitive business landscape of the oil and gas industry, along with strict federal and local regulations, requires companies to maintain secure operations and prevent pipeline freeze. That’s why most companies have implemented a methanol injection plan to help ensure maximum uptime while reducing equipment damage.

Methanol works as an antifreeze by lowering the freezing point of water and water-based liquids that can make their way into pipelines. Operators often inject methanol thru standard check valves into gas pipelines because it’s economical and efficient in preventing hydrate formations and reducing the risk of pipeline freeze.

However, optimally injecting methanol thru atomization will increase the dispersion efficiency, reduce usage and decrease corrosion rates caused by the oxygen-laden methanol.

Create an Effective Methanol Injection Plan 

Review these questions. Ask these questions before injecting methanol into your pipelines this winter:

  • Did we have freezing issues last year that we need to address this year?
  • How are we currently injecting methanol?
  • Do we frequently have to increase the methanol rate to battle freezing?
  • Do we over-inject methanol to be on the “safe side”?

Answers to these questions can help determine if you need to reassess your methanol injection plan for this winter.

Chemical pump selection. Overdosing lines with methanol increases the risk of internal corrosion, as well as waste valuable chemicals. But under-injecting methanol can leave pipes at risk of freezing.

Whether you choose electric, solar or pneumatic, it is critical to select a correctly sized pump. It must fit your needs for pressure, volume, and injection method and ensure the seals are compatible with methanol.

Implement a controller. Most chemical pump companies now provide controllers which deliver automated chemical injections to help ensure accurate chemical dispersal at the right time. For example, most have ambient temperature settings, which can be set to activate injection when temperatures drop to a set temperature and stop injection when temperatures rise above that setting.

In other applications, timers can be used to atomize into the process on set cycles instead of the standard continuous method. This can allow extremely low rates to be used with optimal dispersion.

Optimizing the injection. The correct atomizer for the target helps you significantly reduce methanol feed rates by optimizing the dispersal of your methanol. These atomizers also utilize the gas velocity to aid in coverage. Depending on the rate of injection, the cost of adding an atomizer can be saved in methanol costs in an average of 60 days or less.

Identify the injection location. The location of the injection point will determine the effectiveness of any chemical injection, including atomization of methanol. Choosing the optimal injection point and the optimal injection method is just as critical as selecting the correct chemical.

The Sentry Team offers more than 35 years of expertise in preventing internal corrosion and implementing chemical injection systems. Our experts can help you select the optimal product for all the needs you may have.

Contact us at +1-262-567-7256, or complete our online contact form for more information. 

Beginner's Guide to Pipeline Corrosion Mitigation

Topics: Downstream, Upstream & Midstream, Liquid & Slurry, Steam & Water

Written by Bryan Stockburger

Picture of Bryan Stockburger
From chemical application to pipeline corrosion, Bryan Stockburger brings over 14 years of experience to midstream/downstream companies as a regional sales manager for Sentry Equipment. Bryan works extensively with field operations throughout the US and has obtained multiple safety certifications from producers, chemical providers and vendors. He also continues to remain up to date with the industry as an active NACE member.