Tianhong TH-890 Continuous Emission Monitoring System (CEMS)

Overview

The Tianhong TH-890 Continuous Emission Monitoring System (CEMS) is a fully integrated, stack-mounted environmental monitoring platform engineered for long-term, unattended operation in industrial flue gas applications. It operates on the principle of optical scattering (for particulate matter), non-dispersive infrared (NDIR) absorption (for CO, CO₂, SO₂, NO), and electrochemical or paramagnetic detection (for O₂), complemented by certified thermocouple-based temperature sensing, capacitive humidity measurement, and differential pressure-based flow calculation. Designed in strict conformance with China’s Ministry of Ecology and Environment (MEE) standards—including HJ/T 75–2007 (Technical Specifications for CEMS), HJ/T 76–2007 (Performance Requirements and Test Methods), and HJ/T 352–2007 (Data Transmission and Exchange Protocol)—the system delivers regulatory-grade data suitable for compliance reporting, emission inventory compilation, and real-time operational feedback. Its architecture supports both extractive and in-situ configurations, with primary deployment in coal-fired power plants, cement kilns, glass melting furnaces, and industrial boiler stacks where continuous, trace-level quantification of regulated pollutants is mandated.

Key Features

• Multi-parameter simultaneous monitoring: PM (via laser backscatter), SO₂, NOₓ, CO, CO₂, O₂, flue gas temperature, relative humidity, static/dynamic pressure, and volumetric flow velocity
• Modular hardware design enabling field-upgradable sensor modules and redundant data acquisition units (DAUs) for high system availability
• Automated zero/span calibration sequence compliant with HJ/T 76–2007 verification intervals, supporting both manual and remote-triggered calibration events
• Integrated anti-condensation and heated sampling line (180 °C nominal) with particle filtration and moisture removal to preserve sample integrity
• Embedded Linux-based data acquisition and processing unit with dual SD card logging, local display, and RS-485/RS-232/Ethernet communication interfaces
• Real-time data validation per MEE-defined criteria: range check, rate-of-change limit, spike detection, and cross-check consistency between related parameters (e.g., O₂ vs. CO₂)

Sample Compatibility & Compliance

The TH-890 CEMS is validated for use with flue gases exhibiting temperatures up to 200 °C, dust loadings ≤ 10 g/Nm³, and moisture content ≤ 20 vol%. It accommodates acidic gas matrices (e.g., SO₂-rich coal combustion effluent) through corrosion-resistant 316L stainless steel probe housings and PTFE-lined sample lines. All analytical modules undergo factory calibration traceable to national metrological standards (CNAS-accredited reference gases). The system meets HJ/T 75–2007 requirements for installation, operation, and quality assurance—including mandatory 7-day stability testing, 24-hour zero drift ≤ ±2.5% F.S., span drift ≤ ±2.5% F.S., and response time < 200 seconds. Data output formats comply with HJ/T 352–2007 XML schema for secure transmission to provincial and national Environmental Monitoring Information Platforms (EMIP).

Software & Data Management

The TH-890 employs embedded firmware with embedded database (SQLite) supporting ≥ 180 days of second-level raw data storage. The optional Tianhong CEMS Manager desktop software provides audit-trail-enabled configuration, historical trend analysis, report generation (daily/weekly/monthly emission summaries, exceedance logs, calibration records), and automated export to CSV, PDF, and EMIP-compliant XML. All user actions—including parameter changes, calibration initiation, and data export—are timestamped and logged with operator ID, satisfying GLP-aligned record-keeping requirements. Remote access via HTTPS-secured web interface enables authorized personnel to monitor system health, view live trends, and download certified reports without physical site access—facilitating routine QA/QC and regulatory inspections.

Applications

• Regulatory compliance monitoring at Class I & II emission sources under China’s “Total Pollutant Discharge Control” policy
• Real-time optimization of desulfurization (FGD) and denitrification (SCR/SNCR) systems via feedback on SO₂/NOₓ removal efficiency
• Supporting environmental impact assessments (EIA) and post-construction environmental acceptance testing
• Integration with plant DCS/SCADA systems for emission-aware process control
• Long-term emissions inventory development for carbon accounting and green credit reporting

FAQ

Does the TH-890 CEMS support integration with national-level environmental monitoring platforms?
Yes—it implements HJ/T 352–2007 protocol for secure, authenticated data transmission to provincial EMIP nodes and the national MEE Unified Monitoring Platform.
What maintenance intervals are recommended for certified operation?
Per HJ/T 75–2007: daily visual inspection, weekly zero/span verification, quarterly full calibration, and annual sensor replacement or re-certification.
Is the system compatible with ISO 14064 or GHG Protocol reporting frameworks?
While designed primarily for Chinese regulatory compliance, its traceable calibration, auditable data logs, and mass-flow-corrected concentration outputs provide foundational data suitable for scope 1 emissions quantification under ISO 14064-1.
Can the TH-890 operate in high-dust environments such as cement kiln exhaust?
Yes—equipped with automatic reverse-pulse soot-blowing for the particulate monitor and high-efficiency ceramic filter cartridges rated for continuous operation at dust loadings up to 10 g/Nm³.
Does the system meet requirements for legal enforceability of emission data?
When installed, commissioned, and maintained per HJ/T 75–2007 and verified annually by MEE-accredited third-party agencies, TH-890 output qualifies as legally admissible evidence under China’s Environmental Protection Law (Article 25).