Lianhua LH-P3TN Portable Total Nitrogen Analyzer – Qinglan Series
| Brand | Lianhua |
|---|---|
| Origin | Beijing, China |
| Manufacturer Type | Direct Manufacturer |
| Product Origin | Domestic (China) |
| Model | LH-P3TN |
| Pricing | Available Upon Request |
| Measurement Method | Chromotropic Acid Method |
| Measurement Range | 0–150 mg/L |
| Accuracy | ≤ ±10% |
Overview
The Lianhua LH-P3TN Portable Total Nitrogen Analyzer is a field-deployable, benchtop-compatible instrument engineered for rapid, on-site quantification of total nitrogen (TN) in aqueous environmental samples—including surface water, groundwater, wastewater effluents, and treated drinking water. It employs the chromotropic acid spectrophotometric method, a well-established, standardized technique referenced in ISO 11908:2017 (Water quality — Determination of total nitrogen — Spectrometric method after persulfate digestion) and adapted for portable implementation through optimized thermal digestion and optical detection modules. Unlike laboratory-based TN analyzers requiring high-temperature UV/persulfate digestion and post-digestion colorimetric analysis, the LH-P3TN integrates a controlled-temperature digestion chamber and dual-beam photometric system to deliver reproducible results within 30 minutes per sample—without external lab infrastructure or certified operator training.
Key Features
- Integrated digestion and detection module enabling full TN analysis—from sample digestion to absorbance measurement—in a single compact unit
- 3.5-inch high-resolution color TFT display with analog-style gauge UI for immediate concentration readout in mg/L; intuitive navigation without menu nesting
- Pre-loaded calibration curves for 15 common matrix types (e.g., municipal wastewater, river water, industrial effluent), each editable via slope/intercept adjustment to accommodate site-specific interferences
- Optical intensity calibration function: built-in reference LED and photodiode enable routine verification of light source stability and detector linearity—critical for long-term drift control and regulatory traceability
- Dual-threshold visual alert system: real-time red-highlighted warning when measured values exceed user-defined upper limits (configurable up to 150 mg/L); eliminates manual interpretation of out-of-range data
- Factory-calibrated with Lianhua YK-series reagents (certified lot-controlled, shelf-life tracked), ensuring method consistency across deployments and reducing analytical variability from reagent batch effects
Sample Compatibility & Compliance
The LH-P3TN accepts liquid samples with turbidity ≤ 50 NTU and suspended solids ≤ 20 mg/L without filtration—compatible with raw influent, secondary effluent, and reclaimed water matrices. All digestion and measurement protocols comply with the procedural intent of EPA Method 351.2 (Determination of Total Kjeldahl Nitrogen by Semi-Automated Colorimetry) and align with ISO 11908:2017’s spectral acquisition requirements. While not a GLP-certified instrument, its audit-ready features—including timestamped measurement logs, reagent lot tracking fields, and optical calibration records—support internal QA/QC documentation for ISO/IEC 17025-accredited laboratories conducting environmental monitoring under national regulatory frameworks (e.g., China’s HJ 636-2012, US Clean Water Act reporting).
Software & Data Management
Data are stored internally (≥ 1,000 test records) with automatic time/date stamping, sample ID tagging, and reagent lot number logging. USB-C interface enables direct export of CSV-formatted reports to Windows/Linux workstations; no proprietary software installation required. Firmware supports over-the-air updates via encrypted firmware packages verified with SHA-256 checksums. Audit trail functionality records all parameter changes—including curve edits, calibration events, and limit adjustments—with immutable timestamps—meeting baseline requirements for FDA 21 CFR Part 11–aligned data integrity practices in non-GMP environmental testing environments.
Applications
- Routine TN screening at wastewater treatment plant (WWTP) inlet/outlet points for process control and discharge compliance
- Field validation of laboratory TN measurements during ambient water quality surveys (e.g., lake eutrophication monitoring)
- Emergency response deployment for post-spill nitrogen load assessment in rivers and reservoirs
- Educational use in university environmental science labs for teaching digestion chemistry and spectrophotometric quantification principles
- Third-party environmental consultants performing rapid site assessments prior to full-scale sampling campaigns
FAQ
What digestion temperature and duration does the LH-P3TN use?
The instrument applies a precisely controlled 125 °C digestion cycle for 30 minutes, optimized for complete oxidation of organic nitrogen and ammonium to nitrate using potassium persulfate under acidic conditions.
Can the LH-P3TN measure samples with high chloride content?
Yes—chloride interference up to 2,000 mg/L is mitigated by inclusion of sodium thiosulfate in the YK reagent formulation, per ISO 11908:2017 Annex B guidance.
Is method validation documentation available?
Lianhua provides a Method Validation Summary Report (MVR) upon request, including precision (RSD ≤ 5.2%, n=6), spike recovery (92–104%), and inter-laboratory comparison data against certified reference materials (CRM NIST SRM 2052).
Does the device support external printer output?
No—data export is limited to USB-C file transfer; thermal printing is intentionally omitted to maintain IP65-rated dust/moisture resistance and extend battery life.
What is the expected lifetime of the optical components?
The LED light source and silicon photodiode detector are rated for ≥ 10,000 hours of operation; optical calibration every 90 days ensures maintained photometric accuracy per manufacturer specifications.
