CUBIC Gasboard-9031EX Intrinsically Safe Online Coke Oven Gas Analyzer

Overview

The CUBIC Gasboard-9031EX is an intrinsically safe, continuous-emission online gas analyzer engineered for real-time compositional and calorific value monitoring of coke oven gas (COG), blast furnace gas (BFG), converter gas (LDG), and dry-quenching coke circulating gas in metallurgical and energy-intensive industrial environments. Its hybrid detection architecture integrates non-dispersive infrared (NDIR) spectroscopy for CO, CO₂, CH₄, C₂H₂, C₂H₄, and generic hydrocarbons (CnHm); electrochemical detection (ECD) for O₂; and thermal conductivity detection (TCD) for H₂ — enabling simultaneous, multi-component volumetric concentration measurement without cross-interference under high-dust tolerance conditions. The system calculates higher heating value (HHV) and lower heating value (LHV) in real time using standardized stoichiometric algorithms compliant with ISO 6976 and ASTM D3588, eliminating the need for offline combustion calorimetry. Designed for integration into process control loops, the Gasboard-9031EX supports closed-loop optimization of gas blending, combustion efficiency, and safety-critical purge protocols in steelmaking, coking, and integrated ironworks facilities.

Key Features

• Three-module modular architecture: dedicated pre-treatment unit, PLC-based control unit, and multi-sensor gas analysis unit — each independently serviceable and calibrated.
• Robust dry-gas sampling system featuring stainless-steel, electrically heated probe with programmable reverse-purge cycles to prevent particulate accumulation and ensure long-term stability in low-dust (<5 mg/m³) coke oven gas streams.
• Two-stage filtration and single-stage thermoelectric cooling to dew-point suppress moisture condensation, minimizing spectral interference and sensor drift in high-humidity sample matrices.
• Full automation via industrial-grade PLC: synchronized sequence control of sample aspiration, condensate drainage, zero-air calibration, and diagnostic self-checks — requiring no manual intervention during 7×24 operation.
• Intrinsically safe design certified to Ex d IIC T4 Gb per IEC 60079-1 and EN 60079-0, suitable for Zone 1 hazardous areas adjacent to coke ovens, blast furnaces, and gas purification units.
• Real-time thermal value computation: HHV/LHV output derived from measured concentrations using industry-standard enthalpy-of-combustion coefficients per ISO 6976 Annex A, traceable to NIST SRM reference gases.

Sample Compatibility & Compliance

The Gasboard-9031EX is validated for continuous analysis of raw and partially cleaned coke oven gas, blast furnace top gas, and mixed metallurgical off-gases containing up to 100% vol CO, CH₄, and H₂, with typical operating temperatures between 0–60 °C and pressures from 0.8–1.2 bar abs. It complies with key regulatory and quality frameworks including ISO 14644-1 (cleanroom-classified assembly), IEC 61508 SIL 2 functional safety requirements for safety instrumented systems (SIS), and EU Directive 2014/34/EU (ATEX). Data integrity meets GLP/GMP-aligned audit trail requirements through timestamped event logging, sensor health diagnostics, and secure firmware update protocols. While not FDA 21 CFR Part 11 certified out-of-the-box, optional configuration supports electronic signature and audit trail modules compatible with regulated biogas upgrading and carbon credit verification workflows.

Software & Data Management

• Embedded web server interface accessible via Ethernet for remote configuration, trend visualization, and alarm threshold adjustment without local HMI dependency.
• Standard analog (4–20 mA) and digital (RS-485 Modbus RTU, RS-232 ASCII) outputs enable seamless integration into DCS, SCADA, and MES platforms such as Siemens PCS7, Honeywell Experion, and Yokogawa CENTUM VP.
• Onboard data logger stores ≥30 days of 1-minute averaged concentration and thermal value records with UTC timestamps; exportable via USB or FTP in CSV format.
• Comprehensive self-diagnostic suite monitors optical path integrity, detector baseline stability, heater temperature deviation, and zero-air pump performance — triggering configurable relay alarms for predictive maintenance scheduling.
• Firmware supports over-the-air (OTA) updates with cryptographic signature verification to ensure version control and cybersecurity compliance per IEC 62443-3-3.

Applications

The Gasboard-9031EX delivers mission-critical gas composition data across primary and secondary metallurgical processes: real-time CO/CO₂ ratio monitoring for slag basicity control in blast furnace stoves; CH₄/H₂ tracking during coke oven battery pusher operations to optimize by-product recovery; O₂ and C₂H₂ detection in converter gas cleaning trains to prevent explosive mixture formation; and HHV-based dynamic adjustment of gas-to-air ratios in reheating furnace burners. Beyond steelmaking, it serves biogas upgrading plants verifying methane purity prior to grid injection (EN 16723-1), cement kiln alternative fuel combustion optimization, and catalytic cracking unit feedstock characterization in refineries. Its NDIR+TCD+ECD platform ensures accuracy in complex hydrocarbon matrices where GC-based analyzers suffer from column fouling and extended cycle times.

FAQ

What gas components does the Gasboard-9031EX measure simultaneously?
It measures CO, CO₂, CH₄, H₂, O₂, C₂H₂, C₂H₄, and total non-methane hydrocarbons (CnHm) in parallel, with real-time calculation of higher and lower heating values.

Is the system suitable for high-moisture coke oven gas?
Yes — its integrated thermoelectric cooler and dual-stage particulate/mist filter maintain stable operation at sample dew points up to 40 °C, with automatic condensate management.

How often is calibration required?
Zero calibration is performed automatically every 24 hours using built-in zero-air pump; span calibration is recommended quarterly using certified NIST-traceable gas standards.

Can the analyzer be integrated into a plant-wide DCS?
Yes — native support for Modbus RTU (RS-485), 4–20 mA analog outputs, and Ethernet-based OPC UA (via optional gateway) ensures full interoperability with major industrial control systems.

Does the system meet international explosion protection standards?
Yes — certified to Ex d IIC T4 Gb per IEC 60079-1, suitable for installation in Zone 1 classified areas common in coke oven basements and gas booster stations.