Degassing Chemicals for Refineries: How to Get LEL Down Faster

Every refinery turnaround has the same bottleneck: waiting for vessels to degas. You can plan every other task down to the hour, but if your LEL readings aren’t coming down, nobody’s going inside. Crews are standing around. The clock is running. And your turnaround schedule is already slipping.

Degassing is not optional. But it doesn’t have to take as long as it does.

What Degassing Actually Means

Degassing is the process of removing flammable and toxic vapors from a vessel, tank, or piece of equipment so it’s safe for human entry and hot work. In a refinery environment, that means getting the LEL (lower explosive limit) below acceptable thresholds — typically below 10% LEL for entry and below 1% for hot work — and getting toxic gas concentrations like BTEX below their permissible exposure limits.

Traditional degassing involves steaming, ventilation, and sometimes chemical application. It works. But it’s slow, especially on vessels that held heavy crudes, slop oil, or anything with a high aromatic content. BTEX gases — benzene, toluene, ethylbenzene, xylene — are stubborn. They hang around in sludge, scale, and residual films on vessel walls.

The longer your degassing takes, the more your turnaround costs.

The Problem with Conventional Degassing Chemicals

Most degassing chemicals on the market are petroleum-based solvents. They dissolve residual hydrocarbons, which helps release trapped gases. But here’s the catch — they also contribute their own vapor to the space. You’re adding VOCs to remove VOCs.

That’s why you’ll see LEL readings bounce around during conventional degassing. The readings drop, then spike, then drop again. Every spike resets the clock on your entry permit.

On top of that, these products are flammable. You’re spraying a flammable chemical inside a vessel that already has a flammable atmosphere. The safety implications should be obvious.

How Hasten Cleanse Handles Degassing

Hasten Cleanse attacks the degassing problem from a different angle. Instead of dissolving hydrocarbons with more hydrocarbons, it uses fatty acids and surfactants to bond to hydrocarbon particles and physically suppress their vaporization.

Here’s what that looks like in practice:

1. Apply Hasten Cleanse to the vessel interior — spray, fog, or circulate depending on the application.

2. The product bonds to residual hydrocarbons on walls, floors, internals, and in sludge.

3. Flash point rises immediately. The vapor being released from those hydrocarbons drops off because the chemistry is preventing vaporization.

4. LEL readings drop and stay down. No bouncing. No spikes. A steady decline to safe entry levels.

Because the product is water-based and non-flammable, it adds zero vapor load to the space. You’re only removing gases, not adding them.

Time Savings That Actually Show Up on the Schedule

We’ve seen refineries cut their degassing time by up to 80% using Hasten Cleanse compared to conventional methods. On a turnaround where every hour of downtime costs tens of thousands of dollars, that’s not a marginal improvement — it’s a game changer.

Here’s why it’s faster:

No vapor contribution from the chemical itself. LEL drops are clean and consistent.
Works on BTEX gases specifically. The surfactant chemistry is effective against the aromatic compounds that are hardest to degas.
Less residual hydrocarbon left behind. Because the product is also cleaning while it’s degassing, you get a cleaner vessel with fewer passes.
50% less wastewater generated. Less rinse water means less time managing waste and less disposal cost.

Safe for Your Crews and Your Equipment

Hasten Cleanse is non-hazardous, non-flammable, non-corrosive, and biodegradable. It’s TSCA compliant. It won’t damage vessel internals, coatings, or metallurgy. It works in both freshwater and saltwater rinse applications.

No bacteria, no microbes — just chemistry. Fatty acids and surfactants doing what they’re designed to do.

Your gas testing crew will notice the difference on the first vessel. LEL comes down faster, benzene readings come down faster, and the vessel is ready for entry and hot work sooner than anyone expected.

Prove It on Your Next Turnaround

We’re not asking you to rip and replace your entire degassing program on faith. We’re asking you to let us run a side-by-side comparison on one vessel during your next turnaround. Our product against whatever you’re currently using.

If Hasten Cleanse doesn’t outperform it, you haven’t lost anything. If it does — and it will — you’ll know exactly how much time and money you can save across the rest of the turnaround.

Call 832-655-7763 or email info@hastenchemical.com to set up a demo before your next turnaround.