Reliable and continuous measurements of dissolved oxygen have become of vital importance in many areas of the water/wastewater treatment facilities. The availability of accurate and timely measured concentration values is an absolute need for process monitoring and dynamic process control to ensure an efficient plant operation.

For more than 50 years now, WTW has been recognized as a leader in the field of Dissolved Oxygen measurements. Innovative technologies, creative and continuous product development, and extensive application expertise have resulted in superior instruments and systems of outstanding performance, reliability and design for the most precise online measurements available. The optical D.O. sensor FDO® 700 IQ combines state-of-the-art technology with application applied benefits.

WTW has been continuously designing, manufacturing and satisfying the demands for reliable dissolved oxygen measurements with the most advanced online systems available anywhere.

The WTW product line includes a wide range of precision D.O. sensors and monitors as well as the revolutionary IQ SENSOR NET system so that the optimum system configuration can be chosen for the particular application.

Smell, taste and turbidity are the most important indicators for the quality of potable water.
At the effluent of a waste water treatment plant, turbidity is a quantitative measure of remaining undissolved solids, indicating malfunctions within the treatment process. Turbidity can be measured relatively simple on-line with optical methods. Therefore, turbidity is extremly suitable for measuring the cleaning efficiency of wastewater treatment plants.
Turbidity is typically determined using 90 degree scattered light principle in compliance with EN ISO 7027.

Measuring principle
By the passing of optical radiation through a dispersing system, dipersed solids reduce radiation power by transforming it into another form of energy. This effect is called absorbtion. The ratio of penetrating to emitting light beams is measured as turbidity.

Factory calibration
The online-sensors from WTW are precisely factory calibrated with a “multi-point” calibration. The calibration is very stable – so further calibration is not needed. Formazine is used as a calibration standard – it is diluted to the necessary concentrations.

A continuous gravimetric analysis is not possible in waste water treatment process – therefore indirect methods like turbidity measurement are used. The concentration of suspended solids is a very important process parameter for today’s sludge treatment. Total suspended solids can be determined online using scattered light or light absorbance. Under normal conditions there is a good correlation to gravimetric analysis.
For the most important sludge characteristics, WTW has defined so called matrix types – with this stored data, even without customer specific calibration a good correlation to total suspended solids concentrations can be achieved.
However, sludges can be totally different – concerning coloration, particle size and structure. Threrefore of course a “multi-point” user calibration is possible. This can be done also with the mandatory required gravimetric determination of total suspended solids.

Turbidity Measurement according to the Nephelometric Principle:
Using this principle, scattered light is measured at an angle of 90 degree. This method is ideal for low and medium range turbidity up to 4000 FNU. In compliance with EN 27027 and ISO 7027, infra red light with a wavelenght of 860 nm is used. This wavelength is outside of the visible range – thus potential coloration of the sample does not effect the measurements.

Measuring Principle of Suspended Solids:
With increasing concentration of suspended solids, particles will interfere with each other. With this increasing number, not every particle is reached by the light source or the reflected light is not detected by the receiving device – thus incorrect values are measured. So the 90 degree scattered light method used for the turbidity measurement can only be used for lower concentrations.
For this reason WTW uses two methods of measurement – depending on the concentration. For lower concentrations, a scattered light method is used, in case of higher concentrations, the backscatter method is the better choice.

The PO4 module uses the vanadate/molybdate method (yellow method) for determining the orthophosphate content. A reagent reacts with phosphate in the sample to color the sample solution yellow. The intensity of this color is recorded photometrically and evaluated as a measure of the phosphate content.

• Simultaneous analysis of up to three parameters
• Easily upgradeable
• Reliable & Accurate

The TresCon® ’s individual system components, the central control unit and the self-contained analyzer modules, have heir own microprocessors which can perform specific tests independently. The controller and the module communicate via high speed internal connections. Real-time control of the most difficult tests are easily accomplished with the TresCon® ’s superior design. System can be custom designed to meet the operator’s needs.

• System Controller Module
• Analysis Modules:
  NH4-Module (Ammonium-Nitrogen)
  NO3-Module (Nitrate-Nitrogen)
  NO3/SAC-Module (Nitrate-Nitrogen and SAC)
  NO2-Module (Nitrite-Nitrogen)
  PO4-Module (Orthophosphate)
  ΣP-Module (Total Phosphorus)
• System Mounting
• Supplies Tray

The technical data of the TresCon® modules NH4 analyzer module (Ammonia-Nitrogen), OA 110, NO3 analyzer module (Nitrate-Nitrogen), ON 210, NO2 analyzer module (Nitrite-Nitrogen), ON 510, PO4 analyzer module (Orthophosphate), OP 210/MB1, PO4 analyzer module (Orthophosphate), OP 210/MB2, PO4 analyzer module (Orthophosphate), OP 210/MB3 and NO3/SAC analyzer module (Nitrate-Nitrogen and SAC), OS 210 can be found in parameter section* Nitrogen and Phosphate

TresCon® Uno – Online-Analysis – reliable · compact · economical

• Compact dimensions
• Economical
• Easy to Use

The new TresCon® Uno uses a single channel version of our popular multi channel TresCon® Analyzer. The TresCon® Uno instruments are designed for control and monitoring at waste water treatment plants. The compact size of TresCon® Uno at a reasonable price offers to the user a good price-performance-ratio for the measurement of nutrient parameters.

TresCon® Uno consits of a basic unit, an analyzer-module, and a reagent tray. System can be wall mounted.

Detailed technical data: see TresCon® modules in parameter section* Nitrogen and Phosphate

Ammonium:	0.05 ... 1000 mg/l NH4-N	*See also auch OA 110
Nitrate:	0.10 ... 60 mg/l NO3-N	*See also ON 210
Nitrite:	0.05 ... 1.200 mg/l NO2-N	*See also ON 510
Orthophosphate Range 1:	0.05 ... 3.00 mg/l PO4-P	*See also OP 210
Orthophosphate Range 2:	0.10 ... 10.0 mg/l PO4-P	*See also OP 210
Orthophosphate Range 3:	0.10 ... 25.0 mg/l PO44-P	*See also OP 210
Nitrate/SAC:	0.10 ... 60 mg/l NO3-N / 0.10 ... 200 m-1	*See also OS 210

 

Device system equipped with vacuum technology for frostfree roofed installation with mains supply. This robust and compact instrument contains proven components and is easy to operate. Controls were reduced to an absolute minimum. The operator guidance is menu driven showing all relevant parameters in the display. Thus providing a system which is fully sufficient for a multitude of tasks at a very favorable price-performance ratio. The addition of the IsoBox and cable connection accessory components provides the user with an inexpensive version for 2 h composite samples. With this powerful and reliable device, the operator has a low cost sampling instrument at his disposal which is reduced to core functionalities.

For permanent stationary use in water and wastewater monitoring measuring networks, automatically self-emptying samplers are available from the PB 150-SE 12 series equipped with 12 or PB 150-SE 24 equipped with 24 sample vessels. These devices operate with proven low maintenance and self-cleaning vacuum technology. The sample vessels are available in glass (Duran 50) and are easily extractable for cleaning. The bottle is sealed and emptied by means of robust constriction hose valves. The fractioned sample in the device is automatically discarded (emptied) or manually extracted for analysis. Immediately after emptying a sample which is no longer required, the relevant bottle is rinsed with pressurized clean water before it is refilled. These devices can store up to 12/24 reserve samples without supervision. In case of serious disruption of operation or other events, event samples can be taken. The PB 150-SE devices are thus not only suitable for “around the clock sampling” for routine monitoring tasks, but also for event sampling or for a combination of both. Sampling is traceable by means of the program and error memory readout on the display or can be documented and programmed from a PC using the communication software.

Portable sampler PB 13 with vacuum technology for universal applications. Thanks to its energy saving functionality, a large number of sample cycles or comprehensive sampling programs, respectively can be performed with just one battery charge. PB 13 can be mounted directly on all common storage containers or onto the IsoBox, which is available in different versions. When combined with IsoBox, it provides the user with a practical and modularly extendable system with passive cooling. IsoBox is not only suitable for temperature control of samples but also for safe protected sample transport.

The portable sampler PB 17 with vacuum technology and its immensely compact build is also suitable for field use in difficult terrain. With its large utilizable sample capacity of 24 x 1 l segment bottles, it is particularly suitable for extensive monitoring tasks and load determination. The lower part of the device has a double-wall insulation and offers full sample protection and a passive cooling facility with dry ice or cold storage accumulators. The cover, which is equipped with a lock, offers protection against the elements and unauthorized access. Its easy-to-change rechargeable battery with plug connection prevents downtimes caused by battery charging and facilitates a high level of availability.

With up to 6 individually configurable measuring channels, the MULTILINE 1000 terminal is a very flexible measuring system for drinking water analysis. The system is pre-assembled on a wall mounting panel for immediate use. Just connect the power and sample flow – and it’s ready to go.
• Digital interface (RS 232/RS 422/RS 485)
• 4 x 0/4 … 20mA outputs
• 4 x potential-free relays for limit value/alarm function (timer function programmable)
• Metal housing, protection class IP 65
• Large backlit display with touch screen

Correctly dosed: chlorine measurements
For disinfection monitoring, three amperometric type chlorine electrodes are available.
• Free chlorine: The FCML 412 is suitable for measurements with changing pH values (pH 4 … 9, pH compensation integrated in the sensor).
• Free chlorine: The FCML 68 is suitable for measurements with a relatively constant pH value of approximately pH 7*).
• For total chlorine, the TCML is available.
All measuring cells are supplied with the D-Cl flow-through armature.
*) If the pH value is measured simultaneously, the measured value can be pH-compensated via the MULTILINE 1000.

High precision measurement: pH, Cond, ORP
The flow-through armature has three slots for 13.5 screw threads. Integrated in the screw coupling, all three built-in sensors can be removed together and thus be rapidly and easily calibrated or serviced with the aid of the calibration console.
• SenTix® ML 70 combination electrode
pH combination electrode optimized for drinking water, with gel electrolyte and S7 plug connector
• LR ML conductivity cell
Very robust synthetic two electrode cell with a large measuring range of 0.1 to 20 mS
• SenTix® ML ORP combination electrode
ORP combination electrode for exact ORP measurement

Constant flow: flow measurement
The flow measurement is used to control the optimal incident flow for continuous operation.

Ready-to-use system pre-mounted on a panel consisting of pH/ORP transmitter, pH/ ORP electrode, flow-through cell and tubing
• Special electrode for drinking water
• Low maintenance
• Transmitter with PID control function

Ready-to-use system, pre-mounted on a panel, consisting of D.O. transmitter, D.O. electrode, flow-through cell and tubing
• Low maintenance
• Wide measuring range (0 … 20 mg/l)
• High resolution (± 0.01 ppm)

Ready-to-use system pre-mounted on a panel consisting of conductivity transmitter, conductivity cell, flowthrough armature and tubing
• 2-electrode graphite cell
• Integrated temperature measurement
• Wide measuring range: (0 … 200 mS/cm)

Ready-to-use system pre-mounted on a panel consisting of Cl transmitter, special electrodes for free and total chlorine, flow-through cell and tubing
• Membrane covered sensors
• No reagent consumption

The analyzer operates photometrical with the DPD method according to US EPA.
The reagents are supplied in dry state. For an operation of 30 days it is only necessary to fill them up with water.