Biogas Flow Meter Selection Guide

Accurate biogas flow measurement is essential for the stable operation, energy efficiency, and economic performance of biogas projects. Whether used in agricultural digesters, landfill gas recovery, or industrial wastewater treatment, selecting the right biogas flow meter directly impacts data reliability and system safety.

With the rapid growth of renewable energy projects worldwide, biogas flow meters are evolving toward higher accuracy, intelligence, and durability. This guide provides a clear overview of biogas flow meter selection points, compares mainstream technologies, and recommends trusted international and domestic brands to help engineers and project owners make informed decisions.

1. Core Selection Criteria for Biogas Flow Meters

1.1 Choosing the Right Flow Meter Technology

Different biogas flow meter types are suitable for different operating conditions. Selecting the correct principle is the foundation of reliable measurement.

Thermal Mass Flow Meters

Thermal mass flow meters are the most commonly used solution for biogas measurement.

Key advantages:

• Direct mass flow measurement without temperature or pressure compensation

• Excellent low-flow sensitivity (as low as 0.1 m/s)

• No moving parts, resulting in high reliability and low maintenance

Important note:
They are best suited for dry biogas. Excessive moisture or condensation can affect accuracy.

Vortex (Vortex Shedding) Flow Meters

Vortex flow meters are widely used in stable gas flow applications.

Advantages:

• High accuracy (typically ±1.0%)

• Wide turndown ratio (often ≥10:1)

• Minimal influence from gas density, pressure, and temperature

Limitations:

• Requires sufficient straight pipe lengths (upstream ≥10D, downstream ≥5D)

• Less suitable for very low flow rates

Coriolis Mass Flow Meters

Coriolis flow meters offer the highest measurement accuracy available.

Key features:

• Accuracy up to ±0.2%

• Simultaneous measurement of mass flow, density, and temperature

• No straight pipe requirement

Typical applications:
Trade custody transfer, high-precision energy accounting, and critical measurement points.
Consideration: Higher initial investment cost.

Gas Turbine Flow Meters

Gas turbine meters measure flow based on turbine rotational speed.

Advantages:

• High accuracy (up to ±0.5%)

• Excellent repeatability

Limitations:

• Sensitive to gas cleanliness

• Not recommended for biogas with high impurity or particulate content

1.2 Matching Key Technical Parameters

Accurate biogas flow meter selection requires careful parameter matching.

Flow range:

• Determine Qmin, Qnormal, and Qmax based on actual biogas production

• Recommended operating range: 30%–80% of full scale

• Due to production fluctuations, a turndown ratio ≥10:1 is preferred

Operating conditions:

• Typical biogas temperature: 20–40°C

• Typical pressure: 0–50 kPa

• Maintain at least 20% safety margin for temperature and pressure ratings

• For H₂S-containing biogas, 316L stainless steel or equivalent corrosion-resistant materials are recommended

Accuracy requirements:

• Process monitoring: ±1.5%

• Energy management: ±1.0%

• Custody transfer: ±0.5% or better

• Repeatability (≤0.2%) is critical for stable process control

Explosion-proof certification:

• Biogas contains methane and is highly flammable

• Minimum requirement: Ex d IIC T4 Gb

• International projects should comply with ATEX or IECEx standards

1.3 Installation and System Integration

Installation conditions:

• Vortex meters: strict straight pipe requirements

• Thermal meters: relatively low straight pipe requirements (upstream ≥3D, downstream ≥1D)

• Coriolis meters: almost no straight pipe requirement

• Avoid excessive vibration and improper mounting orientation

Output signals and communication:

• Standard: 4–20 mA and pulse output

• Digital protocols: Modbus RTU, HART, Profibus DP/PA

• Advanced options: LoRaWAN, NB-IoT for remote and distributed monitoring

Environmental protection:

• Minimum enclosure rating: IP65

• Outdoor installations may require insulation or heat tracing to prevent condensation

2. Leading Biogas Flow Meter Brands Overview

2.1 International Premium Brands

Endress+Hauser
A global leader in flow measurement. Its Proline thermal mass flow meters feature Heartbeat Technology for online self-verification, ensuring long-term accuracy. Widely used in large-scale biogas and landfill gas projects.

Emerson (Micro Motion & Rosemount)
Known for Coriolis and vortex flow meters with exceptional reliability. Emerson’s Plantweb digital ecosystem supports predictive maintenance and advanced diagnostics, ideal for high-standard industrial biogas systems.

KROHNE
Renowned for German engineering quality. OPTIMASS Coriolis and OPTISWIRL vortex flow meters perform reliably even under fluctuating moisture and impurity conditions, with strong market presence in European biogas projects.

2.2 Leading Domestic Brands (Cost-Effective Solutions)

Chongqing Chuanyi
A major Chinese instrumentation manufacturer. Its thermal gas mass flow meters are widely deployed in domestic biogas projects, offering stable performance and 30–50% cost savings compared with imported brands.

SAIC
A state-owned enterprise with mature vortex and gas turbine flow meter technologies. Particularly strong in municipal biogas recovery and wastewater treatment applications.

2.3 Emerging and Innovative Brands

Aister
A fast-growing brand focusing on smart vortex flow meters and IoT integration. Its cloud-based monitoring platform is suitable for unattended and distributed biogas stations.

SURE
Specialized in small and medium flow measurement. Known for flexible customization and fast delivery, especially suitable for laboratory-scale and specialty biogas applications.

3. Recommended Configurations by Application Scenario

Large-Scale Biogas Plants (Daily Output > 5,000 m³)

• Recommended solution:
  Coriolis flow meters for custody transfer + thermal mass flow meters for process monitoring

• Preferred brands: Endress+Hauser, Emerson, Chongqing Chuanyi

• Key focus: Accuracy ≤ ±0.5%, redundancy, online diagnostics

Medium-Sized Biogas Projects (1,000–5,000 m³/day)

• Recommended solution:
  Thermal mass flow meters as the primary option

• Preferred brands: Chongqing Chuanyi, SAIC, Aister

• Key focus: Cost-effectiveness, ±1.0% accuracy, remote data transmission

Small and Distributed Biogas Stations (<1,000 m³/day)

• Recommended solution:
  Intelligent vortex or compact thermal flow meters

• Preferred brands: Aister, MICROSENSOR

• Key focus: Easy installation, low maintenance, IoT connectivity

Conclusion

Selecting the right biogas flow meter requires a systematic evaluation of measurement principle, operating conditions, accuracy requirements, safety certification, and long-term maintenance cost. There is no universal solution—only the most suitable configuration for each application scenario.

By combining appropriate technology with reliable brands, biogas operators can significantly improve measurement accuracy, operational efficiency, and overall project profitability. A well-chosen biogas flow meter is not just a measuring device, but a critical component of sustainable energy management.

If you need professional advice or product recommendations, feel free to contact us anytime.