281.491.2331 13839 West Bellfort Street Sugar Land, Texas
281.491.2331 13839 West Bellfort Street Sugar Land, Texas
ISO 9001:2015
U.S. Patents
90 + U.S. Patents
Since 1954
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Where to Use

  • City Gate Stations
  • Distribution Pipelines
  • Municipalities
  • Renewable Natural Gas (RNG), Biogas, and Biomethane Odorization
  • Grain Dryers
  • Industrial Plants

Work Smarter, Not Harder

Welker’s all-in-one, one-of-a-kind pumpless vapor injection odorizer for proportional to flow natural gas odorization in low, high, and variable flow conditions.

Environmentally Friendly Operation and Maintenance

Zero Emissions

Unodorized upstream gas is conditioned for use as system supply gas. This filtered and regulated gas is metered by the solenoids at controlled intervals to serve as the blanket pressure source for the odorant tank, thus no gas is emitted to the atmosphere.

No pumps, no problems. Without odorant pumps, the ECOsystem™ has few moving parts to maintain, making it the standard for reliability in the industry. All serviceable components are upstream of the odorant supply tank, meaning maintenance is odorant-free.

Automatic Odorization

Human vs. Machine

Traditional bypass odorizers are a thing of the past. Using modern technology, the ECOsystem™ eliminates the need for manual valve operation while also ensuring precise proportional to flow odorization. The incorporated Programmable Logic Controller (PLC) receives output from the flow meter on the pipeline and the system flow switch and adjusts the odorization rate accordingly. As seasonal and environmental factors impact the gas flow rate, accurate proportional to flow odorization continues—no crude valve adjustments required.

Electronic Record Keeping

Blazing Audit Trails

Monitor the ECOsystem™ on-site at the intuitive touch screen controller or remotely via Modbus from the comfort of the control room. With the PLC’s real-time tracking capabilities, current system performance data is always at your fingertips. Time- and date-stamped audit data and alarm history are logged to a microSD card and can be exported to a CSV file for accurate reporting, planning, and scheduling.

High Reliability, Low Maintenance

Pumpless is More

The system’s regulator maintains a stabilized pressure differential between the upstream and downstream lines, ensuring consistent odorization without the use of a pump. Gas flow through the system is managed by solenoid valves, which are controlled by the PLC. Any interruptions to operation are limited in systems with identical redundant solenoids. Add a third solenoid for improved system responsiveness to variations in flow rate; the PLC automatically selects the primary solenoid appropriate for the current flow rate, and the third solenoid serves as a backup. Triple solenoid systems—with a low flow, high flow, and backup solenoid—are ideal for locations with wide variations in flow rate.

Safety Is Our Concern


Each tank comes with 110% containment sloped to the drain to protect against contamination and ease clean up.

1 | Skid
2 | Solenoids
3 | Gas Inlet and Filter
4 | Electronic Level Indicator
5 | Regulator
6 | Controller
7 | Tank

The ECOsystem™ provides 110% containment to keep the ground odorant-free in the event of a tank leak.

Low-wattage primary and backup solenoids control the flow of gas through the saturation tank and into the pipeline. Each time a solenoid opens, the controller uses a flow switch to confirm positive flow. If the primary solenoid fails to close, an over-odorization alarm activates and the backup solenoid automatically takes over flow management.

Pipeline gas enters the system and immediately flows into the integrated F-5 Filter/Dryer. Liquids and unwanted particles are filtered out of the gas before it is saturated with odorant.

The electronic level indicator continuously measures the tank odorant level in inches, pounds, or gallons. Odorant level data is stored on the PLC in real-time for instantaneous remote monitoring.

The integrated regulator maintains the required pressure differential between the gas inlet and gas outlet. A stabilized pressure differential allows the ECOsystem™ to evenly distribute odorant to the pipeline system, regardless of varying downstream pressures that can be associated with peak gas usages.

The PLC continuously monitors changes in gas flow rate and automatically adapts the amount of odorized gas released into the pipeline. The PLC features Class I, Div. 2 approval with optional Class I, Div. 1 approval if required for the application. System status and alarms can be remotely monitored via Ethernet, Modbus, or modem. The system alarms conveniently makes the information about operational issues available for assessment prior to going on-site. The system history is logged to a microSD card in CSV format to track important data and settings.

Vaporized odorant saturates natural gas inside the tank proportional to pipeline flow. With the tank located downstream of moving parts, system leaks that might occur from normal wear-and-tear remain odorant-free. Multiple tank sizes are available to accommodate different capacities or flow rates for convenient long-term odorization.


ECOsystem™ Injection Odorization System
Electrical ConnectionAC 120 V
DC 24 V
Odorant Tank Volume20 US Gallons (75 L)
60 US Gallons (227 L)
120 US Gallons (454 L)
250 US Gallons (946 L)
Other Sizes Available