Digester Gas Flow Meters for Municipal & Landfill

A gas digester — also called an anaerobic digester — is a sealed system used at municipal wastewater treatment plants and landfills to break down organic material in the absence of oxygen. This biological process produces biogas, primarily methane and carbon dioxide. Measuring the flow of this digester gas accurately is essential for energy recovery, flare management, emissions compliance, and operational efficiency.

Yes. OSI's OFS series sensors are designed for EPA 40 CFR Part 75 compliance, which governs continuous emissions monitoring at industrial facilities. The sensors use a NIST-certified measurement algorithm and have been deployed at power plants, refineries, and industrial stacks for regulatory emissions reporting, making them suitable for compliance-driven gas flow monitoring applications.

No. OSI optical flow sensors are factory pre-calibrated and feature drift-free measurement, meaning no field calibration is ever required. With no moving parts, maintenance is essentially limited to occasional window cleaning if needed. Built-in automatic calibration check and continuous self-test diagnostics ensure ongoing measurement integrity without scheduled servicing.

OSI's OFS-2000 covers a standard range of 0–100 m/sec, while the OFS-2000F for flare stacks extends the range to 0.03–170 m/sec, accommodating extremely low to very high flow velocities. Both models achieve ±2% accuracy, making them versatile for a wide variety of gas flow monitoring scenarios including low-flow landfill gas flare applications.

Yes. The OFS-2000W model is specifically equipped with Automatic Gain Control (AGC) to compensate for opacity variations caused by particulate matter or moisture — common conditions in wet scrubbers, bag houses, and environments with entrained liquid droplets. OSI's optical scintillation technology is inherently unaffected by pressure, temperature, gas density, or moisture changes.

OSI's OFS-2000 supports RS-232, MODBUS RTU, and optional RS-485, Ethernet, and cellular modem communication, enabling seamless integration into SCADA and data acquisition systems. Power requirements are nominal 12 VDC (max 400 mA), and the unit is solar-compatible, making it suitable for remote municipal and landfill sites with limited grid infrastructure.