Company Profile

CO2 Mass Flow Meter: Measuring Carbon Dioxide Gas and Liquid Density

Quick Answer

A CO2 mass flow meter from Silver Instruments measures the true mass flow and density of carbon dioxide, both as a gas and as a liquid. One Coriolis sensor replaces separate flow and density devices, and it needs no external pressure or temperature compensation for CO2. Send us your pressure, temperature, pipe size and flow range to get a model recommendation and a price from Silver Automation Instruments.

Why a Coriolis Meter for CO2

Here is the thing: CO2 density moves a lot with small changes in pressure and temperature. A volumetric meter reads volume, not mass. You then need a separate density meter, a pressure transmitter and a flow computer to get an inferred mass flow. A Coriolis meter skips all that. It grabs mass flow straight from the vibrating tubes, and it outputs density as a second live signal.

We have seen this on customer sites many times. A gas blending skid in a chemical plant replaces three instruments with one Silver Instruments Coriolis meter. The panel is cleaner, the maintenance drops and the mass balance errors disappear.

Liquid CO2 Density and Flow

Liquid CO2 is common in food and beverage dosing, brewery carbonation, dry ice production and supercritical extraction. At 20 bar and -20 °C, liquid CO2 density sits around 1030 kg/m³. Move the temperature to 0 °C and the density can drop to 930 kg/m³. A Coriolis meter tracks this shift continuously with an accuracy of ±0.2 to ±0.5 kg/m³.

Silver Instruments offers the SILVER-CMF series for liquid CO2. Sizes start at DN15. The sensor comes with a built‑in PT100 and delivers density, mass flow and temperature over a single 4-20 mA HART loop. For food‑grade CO2 injection, we provide 316L stainless steel wetted parts and 3‑A approved surface finishes.

Gas CO2 Measurement

In flue gas monitoring, carbon capture pilots or process gas feeds, the CO2 arrives as a gas. Because a Coriolis meter measures mass directly, it does not need the gas composition or compressibility factors that thermal mass meters and differential pressure devices rely on. You get true kg/h readings even when moisture, pressure or gas blend ratios change.

Most engineers skip this part, but CO2 gas density near its critical point behaves in a highly non‑linear way. A Coriolis meter copes with this without any re‑calibration. We typically recommend a minimum flow of 0.5 kg/h for gas and a meter body sized to keep the pressure drop below 200 mbar on the CO2 line.

Key Specifications You Will Need

When you send us your data, we check a few numbers to propose a meter:

Meter size: DN15, DN25, DN50 (other sizes up to DN150 on request)
Process connection: flange, Tri‑Clamp or threaded
Wetted material: 316L stainless steel, Hastelloy C‑22 optional
Output: 4‑20 mA HART, Modbus RTU, pulse
Hazardous area: ATEX Zone 1, IECEx, Ex d or Ex ia
Accuracy: ±0.1 % of rate for mass flow, ±0.2 kg/m³ for density (liquid)
Fluid temperature: -40 °C to +150 °C

Real Field Example

Last year a beverage plant in Thailand asked us for a meter to dose liquid CO2 into beer during packaging. They ran 350 kg/h at 12 bar and -15 °C inside a DN15 pipe. They needed density repeatability under ±0.4 kg/m³ to hit the right carbonation level. Their previous setup used a turbine meter and a separate density analyzer. The system drifted a lot after CIP cycles.

We supplied a SILVER-CMF015 Coriolis meter with a Tri‑Clamp connection and a local display. The plant wired the 4‑20 mA HART signal straight into their PLC. Six months later they ordered three more for other lines. That is the pattern we see across Southeast Asia, the Middle East and Latin America: once a plant tries a Coriolis meter for CO2, they standardise on it.