Are you tired of wasting time sending an operator to manually open or close the gas line? Our Pulse Bypass Odorization System is an automatic option.

Manual Bypass System

A “Standard” manual bypass odorization system takes advantage of a pressure drop across an orifice plate to channel gas through an external odorant tank and back into the pipeline. It is a low-tech solution that requires an operator to manually open or close the gas line, to allow more or less gas to pass through the odorant tank. The faster the flow of gas the more odorant is required to saturate the gas to the same degree. The flow of gas frequently changes depending on both pressure and temperature from the external environment, normally as a result of seasonal fluctuations.

Manual Bypass new best.png

*The above diagram displays a simplified version of a manual bypass system. As you can see at the top portion, the gas line can be manually adjusted to increase or decrease the amount of odorant that is required to saturate gas depending on flow.


3 Steps to Turn a Manual Odorization System to an Automatic

1. Add a PLC controller to take the signal from a flow meter.

2. Add the valve panel with solenoids.

3. Add a power supply (can be utility, solar, etc).1. The role of a PLC (Programmable Logic Controller) is to continuously monitor gas flows and automatically adapt the amount of odorized gas released into the pipeline. The status of the system can be remotely monitored and alarms can be installed to notify of a potential issue. System history can also be tracked for future usage.

2. Solenoids work as a “switch” to control the flow of gas through the saturation tank and into the pipeline. When the solenoid opens, the controller uses a flow switch to confirm positive flow. There is a backup solenoid in the case that the primary solenoid fails.

3. Unlike the old-fashioned manual by-pass system, the Automated “Pulse” By-Pass Odorization system requires electrical power for the PLC and solenoids. Since many of the sites that utilize manual by-pass systems are remote and a utility power connection is unavailable, a solar array can be used in these cases.

*As a side note, for these three steps to function properly, a regulator must be present to drop the pressure.

Pulse Bypass Odorization System- from OdorEyes

A pulse bypass (automatic) system is an innovative version that allows users to remotely monitor and adjust the gas line depending on the flow of gas. One component that makes this process possible is the controller (PLC), that receives a signal from a flow meter and monitors the current gas flow rate. The controller then sends a signal to the solenoids telling them to “pulse” open and closed at a frequency that will allow odorized gas to flow into the pipeline to match the flow rate of the gas.



– Less maintenance due to fewer moving parts (compared to injection odorizers).
– All moving parts are UPSTREAM of odorization tank, and thus not exposed to the odorant
– The odorant is automatically adjusted to match the gas flow rate.
– Remote monitoring and communication.- Audit data trail.

Pulse bypass new.png* The following diagram outlines the path of unodorized gas that flows through the system to add odorant and then is pushed back to the pipeline.


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