Automatic Total Oxygen Demand Analyzer TOD-810C
The TOD-810 is an automatic TOD analyzer which quickly and accurately measures the total oxygen demand of water from rivers, lakes, marshes, sea areas, factory wastewater and other sources, in either online or offline mode.
This system achieves high-accuracy, stable measurement, which was difficult to achieve with previous BOD and COD analyzers, and reduces use of expensive reagents and other upkeep costs.
The TOD-810 employs Toray Engineering's unique low-temperature sealed combustion system to ensure long-term, stable measurement. It is designed, based on the track record of the previous TOD-800 model, assuming use of the dilution function and stream switching function.
Features
- Enables high-accuracy measurement with stability over the long-term.
- Enables measurement of seawater samples.
- Low-temperature sealed combustion and an automatic washing function enable stable long-term measurement of seawater samples.
- Dilution function (optional) enables dilution by 2-20 times.
- Up to a maximum of 6 streams can be measured by adding a stream switching unit (optional).
- Can handle all types of sample water using various pre-treatment units available as options.
- An offline measurement function is standard.
Principle of Measurement
When organic pollutants are subjected to a combustion reaction under high temperatures in the presence of a catalyst, their various components are converted to stable oxides: C becomes CO2, H becomes H2O, N becomes nitrogen oxides, and S becomes sulfur oxides. If the oxygen necessary for the combustion reaction is supplied as gaseous oxygen in the carrier gas stream, then the oxygen concentration in the carrier gas stream will temporarily drop due to the combustion reaction. Therefore, the TOD value can be determined by measuring the change in oxygen concentration of the carrier gas stream.
Specifications
| Measurement range | 0-50 / 100 / 200 / 500 mg/l 0-500 / 1000 / 2000 /5000 mg/l*1 |
|---|---|
| Dilution function | 2-20 times *2 |
| Stream switching function | 2-6 streams *3 |
| Measurement cycle | 5 min-10 min |
| Measurement method | Automatic intermittent sealed combustion - oxygen concentration difference detection method |
| Calibration method | Span calibration: Manual Zero calibration: Manual (With auto zero function) |
| Conversion function | — |
| Washing | Automatic washing of injection tube and combustion section; Alternate injection of sample and washing liquid (Washing liquid contained in the unit) |
| Range setting | Manual switching, automatic switching driven by external signal |
| Construction | Standalone console, with casters |
| Dimensions | 720W × 560D × 1500H mm |
| Weight | Approx. 180 kg |
| Standard liquid | Potassium hydrogen phthalate aqueous solution |
| Repeatability | Within ±2.5% of full scale |
| Zero stability | Within ±2.5% of full scale/day |
| Span stability | Within ±2.5% of full scale/day |
| Ambient temperature variation | Within ±2.5% of full scale/5 °C |
| Measurement value output | External output: DC4-20mA (Option) Range ID signal no-voltage contact: AC125V, 0.05A |
| Error alarm indication | LED display, Closed contact output in case of error (AC125V, 1A) |
| Alarms | Heater temperature control Detector error Gas mixer error Out of carrier gas Carrier gas pressure drop No sample Out of washing water (Option) |
| Sample conditions | Online measurement: 0.02-0.15 MPa, 500 ml/min or higher Offline measurement: Normal pressure, 100 ml/3 times |
| Reagents/Utilities | Washing liquid: Distilled water Carrier gas: Nitrogen gas, Pressure 0.3 MPa Consumption: 8 Nm3/month |
| Power | AC100V±10V 50/60Hz Approx. 600VA |
| Set up conditions | Indoors 3-40 °C during operation (Temperature gradient 10 °C /hour or less) 45%-85%RH (No condensation) |
Specifications are subject to change due to product improvements.
*1 Only one of these can be selected.
*2 A separate dilution unit (ADU-600) is necessary to add the dilution function.
*3 A separate stream switching unit (VSS-206) is necessary to add the stream switching function. Please designate the necessary streams before determining specifications.
