|
|
|
ChraLab BOD-12 System with 12 sensor heads the BOD Measurement System
Highlights
- User friendly
- Large, illuminated & brilliant graphic display
- Graphical representation of measured values
- USB & SD Card data transfer
- Mercury-free, environmentally-friendly
- Remote control
- User-selectable time span from 1 to 28 days
- Free individual programming of each of the six samples
- Inductive stirring system, 100 – 240 V / 50 – 60 Hz
The ChraLab BOD-12 System is the ideal system for process control or as a secondary test to the Dilution Method. Using a respirometric system solves many of the issues associated with the dilution method for BOD analysis.
- Significantly Reduced Sample Preparation
It's easy to begin collecting data - simply add sample to the bottle, add nitrification inhibitor and place the sensor head on the bottle. There is no need for sample dilutions or seeding the sample. Because this is a respirometric test, concerns regarding air in the sample are eliminated. - Operators do not have to be present at completion of test
Measurements are automatically taken and stored at regular time intervals and can be recalled at your convenience - no more weekend trips to the lab or plant! - Easy and quick interpretation of measurement values
In addition to displaying results of a sample directly in mg/l BOD, the large, integrated, display is able to display the BOD curve which makes it is easy to see and understand measurement data points and trends. In addition, each sensor head has an integrated LED. This allows operators to visually confirm which sample the data is being displayed for and reduces potential confusion or errors over which sample data is presented - Consistent Measurement Conditions
The Automatic Start Function ensures all measurements are taken at an equal sample temperature. When the measurement conditions are consistent across readings, operators do not have to work about temperature or pressure fluctuations skewing results. - Sample Identification and Tracking
The BD 600 interface, makes it easy to assign an identification code or sample name when setting up a new sample. This helps track a sample from the time it is collected and ensures traceability during sample measurement. - Use the remote control
If using an incubator with a glass door, operators can use the supplied remote control to display measurement data for a sample - without even opening the door! This further ensures that samples stay at a consistent temperature which is essential to accurate results.
Description
Respirometric BOD measurement using ChraLab BOD-12 System
The ChraLab BOD-12 System sensor system BOD-12 is a 12 sample system that allows precise measurements of BOD based on the manometric principle. Manometric respirometers relate oxygen uptake to the change in pressure caused by oxygen consumption while maintaining a constant volume. Due to the modern integral pressure sensors, it is not necessary to use mercury for the measurements.
Biochemical Oxygen Demand (BOD)
BOD – biochemical oxygen demand – is an expression for the quantity of oxygen required for biological degradation of organic matter in a waste water sample. BOD measurement is therefore used as a basis for the detection of biologically degradable organic matter in water. The difference between BOD and chemical oxygen demand (COD) is that COD additionally registers biologically non-degradable organic matter.
BOD measurement is therefore an important measurement of the effects of domestic and industrial waste water on sewage plants and outflow points.
Measuring ranges and sample volumes
The BOD level of a sample depends on the quantity of organic matter present, which can vary considerably. The BOD measuring system ChraLab BOD-12 System is therefore calibrated for the various sample volumes and the corresponding measuring ranges listed in the table below. The overall measuring range of the system is 0 – 4000 mg/l. For all measuring ranges, BOD is shown directly in mg/l.
| Range mg/l BOD | Sample Volume ml |
| 0 – 40 | 420 |
| 0 – 80 | 350 |
| 0 – 200 | 240 |
| 0 – 400 | 150 |
| 0 – 800 | 90 |
| 0 – 2000 | 55 |
| 0 – 4000 | 21 |
ChraLab BOD-12 System Principle
Respirometric methods provide direct measurements of the oxygen consumed by microorganisms from an air or oxygenenriched environment in a closed vessel under conditions of constant temperature and agitation. Carbon dioxide produced metabolically by the bacteria is chemically bound by the potassium hydroxide solution contained in the seal cup in the bottle.
The result is a pressure drop in the system, which is directly proportional to the BOD value and is measured by the BOD sensor. The BOD level is then displayed directly in mg/l.
The BOD values are stored automatically in the sensor memory in regulary intervals and can be called up on the large-format display at any time without the need for time-consuming conversion using factors. This means that test series that end on a Sunday can be evaluated during the following week without any problem. Measurement series can be stored on USB stick/ SD card or transfered via USB cable to evaluate the datas on a computer.
The measurement period is user-selectable between 1 and 28 days to suit the application. While short measurement periods are useful for scientific applications, standard BOD measurements typically extend over a period of 5 days – and manometric determination of OECD, for example, generally takes place over a period of 28 days.
Technical Data
| Display | backlit |
| Interfaces | USB SD-Card |
| Power Supply | 100 - 240 V / 50-60 Hz / 3 alkali-manganese batteries (Baby cells/ size C) |
| Auto – OFF | No |
| Measuring Principle | Manometric; mercury-free; electronic pressure sensor |
| Measuring Range | 0-40, 0-80, 0-200, 0-400, 0-800, 0-2000, 0-4000 mg/l |
| Clock | Real Time Clock and Date |
| Measurement Time | User-selectable, between 1 and 28 days |
| Portability | Benchtop |
| Autostart | Yes |
| Measuring Stations | 12 |
| Compliance | CE /EMC according to DIN EN 61326 |
| Protection Class | IP 53 |
| Dimensions | 180 x 230 x 376 mm |
| Weight | 4.1 kg (4100 g, unit with bottles & batteries 5775 g, complete with stirring unit) |
| Weight with Packaging | (4100 g, unit with bottles & batteries 5775 g, complete with stirring unit) |