Have you ever wondered why natural gas smells differently from one place to another? While the mercaptan family compounds are the most used to odorize natural gas, other chemicals, and blends of compounds are developed to satisfy specific applications.
In earlier posts, we share that the government requires natural gas be odorized as a safety measure since it is combustible and odorless. We also discuss that odorant is introduced by either chemical vaporization or chemical injection. We further share the advantages and disadvantages of various odorization systems, whether wick-type, bypass, pulse bypass, drip injection or pump injection systems.
An important aspect of any odorization system is the selection of odorant. Selecting the proper odorant for a system involves an in-depth understanding of the gas that requires odorization, the layout of the gas system including the odorization system and odorant storage tank, and ambient conditions. It is also important to understand what chemical is used to odorize any nearby gas systems. Odorant manufacturers often recommend staying with an odorant utilized in neighboring regimes. Odorants can smell differently, so it is important to use a familiar scent so that people will not be confused by another odor. This is why the natural gas smell is at times described differently, like:
- natural gas smells like rotten eggs
- natural gas smells like kerosene
- natural gas smells like lighter fluid
- natural gas smells like skunk
We also suggest that you consult your odorant manufacturer when selecting the odorant for a system or consider changing the odorant.
Natural Gas Odorants
While some compounds are used by themselves (such as tetrahydrothiophene), most odorants today consist of a mixture of various compounds, such as:
- Dimethyl Sulfide
- Isopropyl Mercaptan
- Methyl Ethyl Sulfide
- Normal Propyl Mercaptan
- Secondary Butyl Mercaptan
- Tertiary Butyl Mercaptan
Odorant manufacturers create custom blends of the noted compounds so that they are more suitable for specific applications. When selecting an odorant or odorant mixture, it is important to understand the odorant’s vapor pressure, odor, soil penetrability, and oxidation resistance.
Another important aspect when dealing with the odorant is that great care should be taken to eliminate or minimize the fugitive odorant emissions during the filling process. Odorant manufacturers can deliver the chemical via truck or transportable containers for smaller applications.
Natural Gas Mercaptan
At GPL Odorizers, we request that our clients buy their selection of odorant from their preferred odorant supplier.