Waste Odor Online Monitoring System: Comprehensive Solution for Urban Odor Control

With accelerating urbanization, waste transfer stations, kitchen waste processing plants, wastewater treatment plants, landfills, and slaughterhouses have become high-complaint zones for residents due to odor issues. These odors not only reduce living quality but can trigger mass environmental complaints, affecting urban image and social stability.

Traditional manual inspections or sniffing methods are subjective and inefficient, unable to provide continuous, objective, and quantifiable data. Recent national regulations, such as the Odor Pollutant Emission Standard (GB 14554-93) and Technical Specifications for Odor Pollutant Monitoring, require online monitoring and direct data transmission for key sources. The Nexisense SGA-900 system was developed specifically to address this challenge.

Complexity of Odor Pollution and Monitoring Challenges

Odors are caused by a mixture of volatile organic compounds (VOCs), sulfur, nitrogen, and ammonia compounds rather than a single gas. Main components include:

• Sulfur compounds: H₂S, methanethiol, dimethyl sulfide

• Nitrogen compounds: NH₃, trimethylamine

• Low-weight fatty acids, indole, skatole, and other organic compounds

Concentrations are often in the ppb–ppm range, with extremely low odor thresholds (as low as 0.001 ppm). Meteorological factors like wind, temperature, and humidity significantly affect dispersion and concentration, making single-parameter monitoring insufficient. Traditional instruments suffer from cross-interference and signal drift.

SGA-900 uses a sensor array strategy to monitor nine key parameters simultaneously while integrating wind speed and direction sensors for combined pollutant-meteorological analysis, providing reliable data for accurate source tracking.

Key Features of the SGA-900

• Nine-parameter monitoring: H₂S, NH₃, methanethiol, TVOC, ozone, formaldehyde, non-methane total hydrocarbons, benzene compounds, odor concentration (OU)

• Imported sensor array: high selectivity and stability, industrial-grade encapsulation

• Meteorological integration: wind speed, direction, temperature, humidity, pressure

• Data transmission: 4G/5G, NB-IoT, Ethernet, HJ212 compatible

• Reliable power design: internal battery with optional solar, data retention during power loss

• User-friendly functions: baseline adjustment, zero calibration, data correction, time sync, historical storage, standard gas calibration

• Easy maintenance: modular sensor design, plug-and-play replacement

• Protection rating: IP65+, suitable for outdoor, humid, dusty, and corrosive environments

  
  

Typical Applications and Installation Strategy

• Waste transfer stations: monitor compression and transport, evaluate deodorization equipment effectiveness

• Kitchen waste plants: monitor sensitive boundary points, respond to nearby complaints

• Wastewater treatment plants: aeration tanks, sludge dewatering areas

• Landfills: leachate collection zones, operational surfaces

• Slaughterhouses and food processing plants: joint monitoring of production areas and plant boundaries

Recommended installation locations:

• Sensitive plant boundary directions (prevailing wind)

• 10–50 m downwind of odor sources

• Near residential areas, hospitals, schools, or other sensitive points

• Based on historical complaints and CFD dispersion simulations

Each system typically includes 1–4 monitoring nodes, forming a grid network.

Data Application and Environmental Management Loop

• Odor concentration trend analysis

• Automatic alarms with SMS notifications

• Odor event source tracking using wind speed and direction

• Deodorization process optimization

• Complaint support: objective exceedance evaluation

Implemented projects have reduced effective complaints by over 30%, improving government-enterprise relations and social stability.

Frequently Asked Questions (FAQ)

1. What are the nine parameters and why are they needed? H₂S, NH₃, methanethiol, dimethyl sulfide, TVOC, ozone, formaldehyde, non-methane total hydrocarbons, odor concentration (OU). Multi-parameter monitoring provides comprehensive assessment of complex odors.

2. How important are wind speed and direction? Essential for source tracking; without them, it is impossible to determine origin or dispersion.

3. Sensor lifespan and replacement: 2–3 years; modular plug-and-play design allows quick replacement without factory recalibration.

4. How is direct data transmission ensured? Supports HJ212, via 4G/5G or wired networks, with data retransmission to ensure completeness.

5. How to avoid false alarms from odor fluctuations? Multi-level thresholds, delay confirmation, wind filtering, and dynamic baseline reduce false triggers.

6. Coverage area: 50–300 m radius; large sites require multiple nodes (3–8) for full coverage.

7. Supports solar power? Yes, with backup battery; low power consumption, IP65 rated for all-weather outdoor use.

8. How does data optimize deodorization and reduce operating costs? Correlates odor concentration with equipment status, avoids overuse of chemicals, and reduces cost.

Conclusion

Urban odor management has evolved toward data-driven scientific governance. Nexisense SGA-900, with multi-parameter integration, meteorological coupling, reliable transmission, and easy maintenance, provides a practical and efficient tool for industries with high odor emissions.

Installing a professional odor monitoring system not only helps comply with regulations and reduce complaints but also enables process optimization and environmentally friendly, cost-effective operations. Technology transforms odor management into a scientific, sustainable process.