Homogeneous Gas Mixer

For many processes, very accurate compositions of gas are required, which means simply adding two or more gas streams together isn’t sufficient. Our homogeneous gas mixer enables operators to create accurate as well as precise gas compositions of two or more gases. Furthermore, our gas mixing systems allow a repeatable and reliable process that helps eliminate discrepancies. They also ensure that operators have access to the exact gas compositions their processes require at any time. Mixing your own gas increases process efficiency in addition to reducing the cost of having to purchase premixed gas cylinders.

• create homogeneous gas mixtures from percentages down to ppm-ranges
• high accuracy and repeatability in addition to a fast response time
• flow ranges from 300 mln/min up to 10,000 mln/min
• pressure rating up to 100 bar
• available with 1/4″ or 6 mm connections

Automated Gas Mixing System

Up to 12 gas cylinders can connect to an equal amount of mass flow controllers. With accurate control, the gas flows enter a gas mixing chamber where it becomes a homogeneous mixture. It can then flow directly to the processes for example, to a gas chromatograph. It can also be compressed for later use.

The ISO 6145-7:2009 standard describes a procedure to prepare calibration gas mixtures using commercially available thermal mass flow controllers. Calculation of the accuracy of the final gas composition that leaves the gas mixer occurs through special software. This software considers the uncertainties in the gas flows as well as the gas composition of the initial gas cylinders.

Compared to the purchase of gas cylinders with premixed gas mixtures, the preparation of gas mixtures on-site has some advantages. For example, the lifetime of premixed gas mixtures can be limited and expired gas can be costly. In addition, the costs for these gas cylinders can be quite high. And you can’t always be sure that the concentration of the gas is still good or that the mixture is still homogeneous.

Therefore, it can be beneficial for users to prepare gas mixtures on their own with very low concentrations of specific compounds. As an operator, you no longer need to invest in cylinders of premixed gas mixtures. It also gives the flexibility and freedom to calibrate an analyzer in your own time. Overall, our gas mixer provides great value through high accuracy and flexibility and through capabilities from its Modbus protocol.

How to Create Custom Gas Mixtures

There is more to creating gas mixtures than simply combining two gas streams into one. For instance, if you need to dilute 1 mln/min of dopant with 10 ln/min of dilution gas, you cannot expect to obtain a homogeneous mixture unless an appropriate mixing chamber is used. Luckily, our homogenous gas mixer offers precision in low flow gas mixing applications.

A user-friendly, preprogrammed touchscreen interface also allows users to easily input the desired composition of the gas mixture. Gas then automatically flows from gas cylinders and into a gas mixing chamber using gas flow meters and controllers. There, the gas mixes homogeneously, which is ready for direct use in processes or it can also undergo compression for later use. This process is both accurate as well as repeatable and users of nearly any experience level can operate our gas mixer. With our system, it’s simple to blend your own high purity, homogenous gas streams on site.

Common Uses of a In-House Homogeneous Gas Mixer

• mixing reference gas for analyzers
• calibrating gas chromatographs
• food and beverage production for example, the fermentation of beer

Homogenous Gas Mixer Flow Diagram