There are very specific federal guidelines for UST's (40 CFR 280) for installation and monitoring, etc. However, underground odorant tanks are generally not classified as UST's. As standard practice, underground odorant tanks should be classified as a part of your pipeline. They would then be treated the same as any underground pipeline, so the specific regulations and programs you have in place for monitoring your pipeline would apply also to your odorant tank.

The Department of Transportation regulates the odorization of gas. The details can be found in code 40 CFR 192.625 (Pipeline Safety).

Standard practice in this case is to mix the odorant with hexane to dilute it. Generally the mix is 4 to 1 hexane to odorant. We can mix this diluted odorant for you and ship in various small packages. Unfortunately, diluted odorant won't work in a by-pass system. The vapor pressure is very different between odorant and hexane, so you won't get a good consistent odorization. This may result in the over or under odorization of your gas. Diluted odorant will only work in an injection system. A possible solution we recommend is to consider switching your odorant to THT (Thiophene). It works very well for bypass systems where the gas flow is inconsistent and/or low. It is difficult to over-odorize with THT as the odorant intensity is not as strong.

Any odorant blend can used since it is being injected directly into the gas flow. Differences in component vapor pressures do not affect performance.

Single-component odorants (i.e. THT, or blends where components have similar vapor pressures, e.g., all mercaptan blends or blends with TBM and MES) can be used in evaporative systems. Do not use mercaptan/DMS or mercaptan/THT blends. The components in these blends have widely differing vapor pressures, which results in inconsistent odorization of your gas.

Odor-Tech can supply your bulk needs using our diverse fleet of trailers, from a remote 100-gallon storage tank to a high-volume, 10,000-gallon tank. Our partner, Bayou Engineering offers various cylinders, pails, and drums to meet your needs.

No, all blend components are soluble in each other. Not only will there be no reaction, but mixing will not diminish odorant effectiveness.

Yes. The same materials of construction are recommended for all odorant blends.

Yes! During an odorant delivery to a number of your stations, we can transfer the odorant from the old tank to the new tank on-site or to another tank off-site if the old tank is not being replaced.

In a flared delivery, a liquid hose is connected to a liquid line on the tank, which is preferably fitted with a dip-tube. The vapor line on the tank which is connected to the flare is opened to vent off any pressure. Pressure is applied to the odorant trailer, and the liquid valves are opened to allow flow to the storage tank. The displaced vapors from the tank are vented to the flare until the delivery is complete. These vapors burn in the flare and are emitted as sulfur dioxide, which raises environmental issues. Additionally, if the tank has a faulty level gauge, it is possible to overfill the tank with odorant, which will cause overflow through the flare, resulting in odorant spillage. This is an environmental problem and also results in false leak complaints. In a "closed-loop" delivery, a vapor hose is connected to a vapor line on the tank in addition to the liquid hose. This is done through the truck manifold, which is connected to a compressor, which pulls pressure off the tank and supplies it to the trailer to allow flow by differential pressure. This allows the delivery to take place without venting to the flare. Also, when performed correctly, a closed-loop delivery removes the chance of tank overfill, and the overall result is a safer, “odor-free” delivery.

The first thing to do is to ensure that the tank and fittings have been properly installed according to the design blue-print, ensuring safe storage of your odorant.

Ensure that the tank is clean and dry. Water in the tank can find its way into your injection lines and in winter conditions can freeze, stopping odorant flow to your gas. Pressure test the tank and check for any leaks at flange connections, valves etc.

Finally, purge the tank with nitrogen or gas to remove any oxygen. Odorant vapors and oxygen can form explosive mixtures.

Depending on the blend density, 5,500-6,000 gallons can be delivered by one truck. Of course, multiple truck deliveries are available.

We recommend placing any materials used to handle odorant, such as towels, etc. in a DOT approved drum and disposing of them as a hazardous waste. These materials are hazardous; you would need to find a facility that could properly dispose of hazardous material.

The actual definition of the term "oil" in the USEPA's Oil Pollution Prevention Act (112.2) is extremely broad. Oil means oil of any kind or in any form, including, but not limited to: fats, oils, or greases of animal, fish, or marine mammal origin; vegetable oils, including oils from seeds, nuts, fruits, or kernels; and other oils and greases, including petroleum, fuel oil, sludge, synthetic oils, mineral oils, oil refuse, or oil mixed with wastes other than dredged spoil. If a site is involved with handling/storing of such materials above certain thresholds (listed in this same rule), then a special plan must be developed and documented at the site which discusses the procedures/protocols followed if a release to the environment were to occur. This plan is called a "Spill Control and Countermeasure Plan" (or SPCC plan) and is extremely common at industrial manufacturing sites (usually due to the presence of diesel fuel for boilers/incinerators, etc). The Arkema sites involved with odorants/mercaptan all have site-specific SPCC plans that have been signed/stamped by a professional engineer (as required) due to the presence of petroleum-related products/raw materials for production. We interpret this to mean that yes, our plants have this SPCC plan in place because we are using petroleum derivatives to produce odorants. But that odorant is not defined as an oil. So simply storing odorant does not mean you would need an SPCC plan. We are not aware of any of our customers that just store odorant having a specific SPCC plan in place in accordance with this Act. But it's important to note to that Arkema is not responsible for any regulatory determination concerning this issue, and the information above can only be used as guidance, as we are not completely knowledgeable of this Act.

Ethyl mercaptan decomposes to hydrogen disulfide + ethylene. To get ethyl mercaptan to break down you need to crack it with high heat or utilizing a catalyst. Without a catalyst present, it is very difficult to get ethyl mercaptan to decompose. It has been published in literature that the formation of ethylene will occur around 500°C, but the yield is very poor, and not much happens until you are in the range of 600° - 700°C. However, the auto-ignition point for ethyl mercaptan is 300°C, flash point is -54°C, and the boiling point is only 35°C . So it will most likely ignite or dissipate, prior to decomposition.

Thank you for your interest in Arkema's odorant product line. Unfortunately, we do not support the use of our product for this application. We will not sell our gas odorant for this type of application to anyone.

Always inject liquid, either as a lump injection before loading, or inject proportional to flow as loading. The larger loading facilities inject proportional to flow.

There should not be any ash content created from ethyl mercaptan. It is 100% organic and burns cleanly.

Water is virtually insoluble in gas odorant and will fall to the bottom of your tank. The number one cause of this is from wet pad gas. To resolve, carefully add heat to your injection lines to thaw the ice buildup. A second option is to add methanol (up to .05%) to dissolve the water layer. Do not add any additional percentage to your tank contents or it could adversely affect your odorant performance.

Pipeline conditions, gas quality, and soil composition.

Please see the chart on the Product Lines page to see which blends are recommended for specific applications.