Lianhua Technology LH-COD-K23 On-Site COD Quick Test Kit
| Brand | Lianhua Technology |
|---|---|
| Origin | Beijing, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | LH-COD-K23 |
| Pricing | Available Upon Request |
Overview
The Lianhua Technology LH-COD-K23 On-Site COD Quick Test Kit is a field-deployable colorimetric assay system engineered for rapid, semi-quantitative determination of Chemical Oxygen Demand (COD) in aqueous samples. It operates on the principle of dichromate digestion under acidic conditions, followed by spectrophotometric measurement of the reduced Cr(III) ion at 600 nm — a method aligned with the core chemistry of ISO 6060 and APHA Standard Methods 5220 B. Designed specifically for time-critical environmental assessments, the kit eliminates the need for benchtop spectrophotometers or reflux apparatus, enabling reliable COD estimation within 15 minutes using only a portable visual comparator or optional handheld photometer. Its robust, pre-dosed reagent format ensures consistent reaction stoichiometry and minimizes operator error in uncontrolled field environments.
Key Features
- Pre-calibrated, single-use sealed reagent vials containing standardized potassium dichromate, sulfuric acid, and silver sulfate catalyst — eliminating manual reagent preparation and associated safety hazards.
- Integrated color scale card with 8 reference bands covering a validated range of 0–150 mg/L COD (as O₂), optimized for low-to-moderate strength wastewater and surface water matrices.
- Compact, shock-resistant carrying case with desiccant-lined compartments, rated IP54 for dust and splash resistance during transport and outdoor deployment.
- No external power supply required; compatible with ambient temperature operation (10–35 °C), making it suitable for vehicle-mounted mobile labs or hand-carried emergency response kits.
- Batch-certified reagents traceable to NIM (National Institute of Metrology, China) reference materials, with lot-specific expiration dates printed on each vial.
Sample Compatibility & Compliance
The LH-COD-K23 kit is validated for use with clarified or filtered samples from municipal wastewater influent/effluent, aquaculture recirculation systems, agricultural runoff, ornamental pond water, and irrigation sources. Turbid or highly colored samples require prior centrifugation or filtration (0.45 µm membrane) to avoid interferences. While not intended for regulatory compliance reporting per ISO 6060 or EPA Method 410.4, the kit meets internal QA/QC requirements for rapid screening, trend analysis, and process troubleshooting. All reagents comply with GB/T 27417–2017 (Guidelines for Validation of Qualitative Test Kits) and are classified as non-hazardous for air and ground transport under IATA Packing Instruction 955.
Software & Data Management
As a visual/semi-quantitative field tool, the LH-COD-K23 does not incorporate embedded electronics or digital connectivity. However, Lianhua Technology provides optional companion tools: a free Android/iOS mobile application (LH-FieldLog) that supports photo-based color matching via calibrated camera algorithms, automatic result logging with GPS timestamping and geotagging, and export of CSV reports compliant with GLP documentation standards. Audit trails, user authentication, and electronic signature functionality are available in the enterprise version for laboratories operating under ISO/IEC 17025 or China’s CMA accreditation framework.
Applications
- Rapid assessment of treatment plant influent surges or effluent excursions during routine patrols or storm events.
- On-farm monitoring of pond water quality in aquaculture operations to prevent hypoxia-induced mortality.
- Pre- and post-disinfection verification in decentralized water reuse systems for agricultural irrigation.
- Field validation of portable electrochemical or optical COD sensors prior to extended deployment.
- Training and capacity-building exercises for environmental technicians in resource-limited settings where access to centralized labs is constrained.
FAQ
Can the LH-COD-K23 be used for seawater or high-salinity samples?
No — chloride interference exceeds acceptable limits above 1000 mg/L Cl⁻. For saline matrices, sample dilution with deionized water and chloride correction using mercuric sulfate pretreatment is required; consult the technical bulletin LH-TB-COD-07 for protocol details.
What is the shelf life of unopened reagent vials?
24 months from manufacturing date when stored at 4–30 °C in original packaging, away from direct sunlight.
Is this kit suitable for regulatory submission under China’s HJ 828–2017 standard?
It serves as a screening tool only. Quantitative compliance testing must be performed using the full HJ 828–2017 reflux method with certified laboratory instrumentation and accredited personnel.
Does the kit include calibration verification standards?
Yes — each kit contains one ampoule of 50 mg/L COD certified reference solution (CRM-LH-COD-50), traceable to NIM, for daily performance verification prior to sample analysis.
How should used reagent vials be disposed of?
Treated as hazardous waste per GB 5085.3–2007 due to residual hexavalent chromium content; disposal must follow local environmental authority guidelines for heavy metal-contaminated laboratory waste.
