Zming Environmental HQ-3600(NO₃) Online Nitrate Analyzer
| Brand | Zming Environmental Technology Co., Ltd. |
|---|---|
| Origin | Jiangsu, China |
| Manufacturer Type | Authorized Distributor |
| Country of Origin | China |
| Model | HQ-3600(NO₃) |
| Measurement Parameter | Nitrate-N (NO₃⁻-N) |
| Instrument Type | Online Continuous Analyzer |
| Measurement Principle | Spectrophotometry (UV-Vis, at 220 nm & 275 nm for nitrate correction) |
| Measurement Range | 0–2 mg/L and 0–10 mg/L (standard), extendable up to 500 mg/L via range switching |
| Resolution | 0.001 mg/L |
Overview
The Zming Environmental HQ-3600(NO₃) Online Nitrate Analyzer is a dedicated, fully automated water quality monitoring system engineered for continuous, unattended measurement of nitrate-nitrogen (NO₃⁻-N) in natural and anthropogenic aquatic environments. It operates on the standardized spectrophotometric method specified in China’s national standard HJ 636–2012 (Determination of Total Nitrogen in Water by Alkaline Potassium Persulfate Digestion–Ultraviolet Spectrophotometry) and aligns with the analytical logic of ISO 11905-1 and EPA Method 353.2 for nitrate quantification. The instrument employs dual-wavelength UV-Vis absorbance detection—measuring at 220 nm for combined nitrate + organic interference and at 275 nm for correction of dissolved organic carbon (DOC) contribution—ensuring robust speciation and minimizing matrix-induced bias. Designed for deployment in fixed-site environmental monitoring networks, the HQ-3600(NO₃) integrates digestion, reagent addition, mixing, reaction incubation, optical detection, and waste handling within a single compact chassis, enabling reliable operation under variable ambient conditions and extended periods without manual intervention.
Key Features
- Capacitive fluid metering technology for precise, low-drift dispensing of sample and reagents—achieving <±1.5% volumetric repeatability across operational temperature ranges (5–40 °C).
- Integrated hardware self-diagnostic suite including real-time leak detection, power-fail recovery with data retention, pressure-sensor-based flow path integrity monitoring, and heater/temperature sensor fault logging.
- Multi-level quality control support: automated blank calibration, standard addition checks, spike recovery verification, and scheduled drift validation—all programmable and traceable via internal audit log.
- Modular optical cell design with quartz cuvette and stabilized deuterium-tungsten light source, delivering long-term photometric stability (<0.5% absorbance drift over 30 days).
- IP65-rated enclosure with corrosion-resistant housing, suitable for outdoor cabinet or sheltered field installation; supports ambient operating temperatures from 5 to 40 °C and relative humidity up to 90% non-condensing.
Sample Compatibility & Compliance
The HQ-3600(NO₃) is validated for direct analysis of raw surface water, treated effluent, riverine influents, estuarine brackish samples (up to 5 g/L TDS), and drinking water distribution system points. Sample turbidity up to 100 NTU is accommodated via integrated filtration and air-bubble removal. The analyzer complies with technical requirements outlined in HJ 353–2019 (Technical Specifications for Online Monitoring Systems of Pollutant Sources) and HJ 354–2019 (Acceptance and Operational Management of Online Monitoring Systems). Its data acquisition architecture supports GLP-compliant record keeping—including timestamped events, user-defined metadata tagging, and immutable storage of raw absorbance spectra—and meets foundational requirements for regulatory reporting under China’s MEP Order No. 39 and local ecological environment bureaus’ QA/QC protocols.
Software & Data Management
The embedded firmware (v3.2+) provides web-based configuration via HTTPS-secured interface, supporting remote parameter adjustment, method scheduling, and diagnostic review without physical access. All measurements are stored locally on industrial-grade microSD with 12-month buffer capacity (1-min interval), and optionally synchronized to SCADA or cloud platforms (MQTT/Modbus TCP) using configurable data push intervals. Audit trails capture operator actions, calibration events, alarm triggers, and firmware updates with digital signature timestamps. Export formats include CSV (with ISO 8601 timestamps), XML (for integration with national EIA platforms), and PDF summary reports compliant with HJ 355–2019 reporting templates. Optional 21 CFR Part 11 readiness package available upon request (electronic signatures, role-based access control, and operation history encryption).
Applications
- Real-time surveillance of nitrate-N in upstream–downstream transects of rivers and lakes for eutrophication trend analysis.
- Compliance monitoring at municipal wastewater treatment plant (WWTP) discharge outfalls per GB 18918–2002 Class I A limits.
- Nutrient loading assessment at river–sea interfaces and tidal estuaries to support coastal zone management plans.
- Performance evaluation of denitrification units in advanced water reclamation facilities.
- Long-term tracking of agricultural runoff impacts in irrigation return channels and reservoir tributaries.
- Baseline characterization and post-intervention verification in constructed wetland restoration projects.
FAQ
What is the required sample pretreatment before analysis?
No filtration or centrifugation is needed for most freshwater matrices; however, samples with suspended solids >150 mg/L should pass through a 63-µm inline sieve. High-chloride or high-organic samples may require optional UV digestion pre-treatment module (sold separately).
Can the instrument measure total nitrogen (TN) as well as nitrate?
The HQ-3600(NO₃) is optimized for nitrate-N only. For total nitrogen, Zming offers the HQ-3600(TN) variant, which incorporates high-temperature alkaline persulfate digestion prior to UV detection.
How frequently does the system require maintenance or reagent replacement?
With daily automatic cleaning and weekly standard verification, typical reagent consumption is ~1.2 L/month (per 10-minute cycle); pump tubing and optical cell cleaning are recommended every 3 months under continuous operation.
Is remote firmware update supported?
Yes—secure OTA (over-the-air) updates are supported via authenticated HTTPS connection; all updates undergo SHA-256 signature verification prior to installation.
Does the analyzer meet international export compliance standards (e.g., CE, RoHS)?
The device conforms to IEC 61326-1 (EMC) and IEC 61010-1 (safety); CE marking is available for EU-bound units upon request with additional EMC testing documentation. RoHS 3 compliance is standard across all PCB assemblies.
