DKK-TOA Corporation, Japan's leading manufacturer of analytical instrumentation has released its new X Series range of laboratory meters for water quality measurement.
The X Series comprises single and dual channel meters that can measure a wide range of parameters including pH, ORP, Conductivity, TDS, Dissolved Oxygen and Ions. A large number of combinations are possible with the extensive range of electrodes and sensors all manufactured by DKK-TOA. Unlike some lower quality conventional electrodes, all X Series sensors are free of Lead and Mercury and are fully compliant with EU ROHS directives. The high end models in the X Series feature full size colour touch screen displays that provide an intuitive "tablet-style" user experience. The display and operating menus have been designed to maximise productivity. Starting a measurement or calibration, switching between measurement modes or changing display layout can all be accomplished from the touch screen.
The large and highly legible full size colour display makes working with these models simply a pleasure.
Model HM-42X pH Meter:
The meters provide an extensive array of interfaces for peripheral devices. These include USB interface for connection to memory sticks or personal computers, printer interface and connections for turntable samplers, stirrers etc..
The meters also feature internal data storage memory for standalone operation. Sample analysis, data handling and data archiving are all in compliance with GLP regulations.
The Model SSM-21P Surface Salinity Meter recently completed third party testing and certification. Independent testing laboratory, Sumitomo Measuring Industries Environmental Co. Ltd. performed extensive testing of the Model SSM-21P. As a result of successful completion of testing, the Model SSM-21P has now gained certification proving that its measurement is equivalent to ISO 8502-9 (the Bresle Method) in accordance with NACE SP0508-2010.
The Model SSM-21P provides an improved method for checking surface salinity of steel surfaces prior to painting. The use of this instrument will improve the reliability of test results and increase the overall efficiency of the preparation and painting processes.
PSPC is a Performance Standard for Protective Coatings for dedicated seawater ballast tanks on all new ships and double-sided skin spaces of bulk carriers that the IMO (International Maritime Organization) has established.
DKK-TOA have released for sale a unique hand held Residual Chlorine meter. The Model RC-31P Residual Chlorine meter provides an instant measurement of residual chlorine by the use of a polarographic sensor. The measurement can be achieved without the inconvenience and human errors associated with conventional reagent based portable instruments.
The meter consists of two sections, a handheld keypad and a sensor assembly. The key pad section features a large, easy-to-read LCD panel. The sensor assembly is available in three versions, a float type suitable for swimming pool applications, a flow through cell suitable for water outlets and a grab sampler type for use with water tanks.
The meter also indicates the sample temperature and includes a built-in-clock. The instrument can store one set of results (measurement, temperature and time) in memory for later retrieval. Power is provided by two standard AA batteries which have an operating life of up to 50 hours.
What is Residual Chlorine ?
Testing for Residual Chlorine is very common in water treatment. The word, "residual", means remainder or that which is left. This test is made to measure the amount of chlorine remaining in the sample at the time the test is made.
For example, 2 ppm of chlorine may be added to a certain water. After a certain contact time, the test is made and indicates that 0.3 PPM chlorine is present. The 0.3 PPM is the chlorine residual. The difference between 2.0 PPM and 0.3 PPM, 1.7 PPM chlorine, was used during the contact time in oxidizing organic matter (bacteria, vegetative matter, sewage, etc.) in the water. This is known as the "chlorine demand" for that period of time. There is no chlorine demand in distilled water.
It is important to note that due to the chlorine demand, a chlorine residual test indicating sufficient chlorine at the plant does not necessarily mean that a test at the end of a main will indicate sufficient chlorine.
There are a number of materials in the lines which can use up the chlorine, such as iron bacteria or foreign matter introduced by backsiphonage.
DKK-TOA's Model RC-31P is portable and can be easily brought to and used at end of distribution points.
Why Measure Residual Chlorine ?
Chlorination has long been the conventional method for disinfection as it is effective and inexpensive. The water company must ensure the water system has a suitable concentration of chorine for a suitable period of time to ensure effective inactivation of bacteria and viruses. Water companies need to monitor chlorine for their due diligence to ensure that their equipment is working and that they are providing potable water to their customers.
The Medical Health Officer may make monitoring a requirement. Monitoring residual chlorine is suggested for three critical areas:
1. Before the first customer to ensure potability. 2. At the chlorinator to ensure the equipment is functioning. 3. At the end of the distribution system to ensure all water is treated.
These checkpoints are typically monitored by small hand held devices. The advantage of DKK-TOA's Model RC-31P is that it can store data for later retrivel and it does not require any reagents to perform its measurement.
Increasingly stringent requirements, growing awareness and understanding of the effects of chlorine on the environment, water quality and greater need for process optimization are strongly prompting many progressive water utilities to more fully optimize the performance, reliability and safety of their chlorination programs.
Where tight control is required, water treatment plants can add an on-line residual control to their chlorinator, using analysers such as DKK-TOA's Model CLF-100. The residual control will measure the residual chlorine level at a set location then send a signal to the chlorine feed equipment. The feeder will automatically adjust the chlorine addition to ensure a constant level of chlorine exiting the treatment plant.
Residual control can be applied to both gas and liquid chlorine feed. Typically, the residual is combined with a flow signal for a “compound loop control”. Using this method, the chemical feed will increase or decrease as the water flow rate changes. The residual analyzer will measure the resulting chlorine dose then bias the dosage to meet a set concentration of chlorine residual. In addition to control, the residual analyzer can output an alarm of low residual. The alarm is immediate therefore it is possible for operation staff to resolve the situation before a boil advisory must be issued.
As the residual chlorine is the last element of a water treatment plant, the importance of tight control cannot be overemphasized.
DKK-TOA Corporation announce the release of their Model SODL-20 Oil-on-water alarm. The Model SODL-20 is the latest development in oil-on-water detection technology and builds on the success of the previous Model SODL-12 which has over 800 installations worldwide. The detection method utilizes a laser beam to monitor the reflectivity of the water surface. The model SODL-20 consists of a sensor module and field mounted display/transmitter.
This latest version offers the following advantages:
No contact with sample.
Detection over a wide variation of distance from the water surface.
Detection of all oil species.
Suitable for use in hazardous areas (intrinsically safe design).
24V, 2 wire operation (signal and power use the same cabling).
DKK Corporation announce the release of their Model FPM-222. This new instrument is capable of measuring both PM2.5 and PM10 type particles. This instrument is currently being tested by the US EPA.
The model HSCA is an on-line process sulphur analyser. It uses a measurement system based on the energy dispersive X-ray fluorescence method and utilises a high sensitivity semi-conductor detector. The analyser has provided accurate and reliable operation for more than two years during rigorous field trails conducted at one of our client’s refineries.
In order to achieve the required sensitivity and minimise noise, the semi-conductor detector is cooled using liquid N2. An automatic supply and control system handles the supply of the liquid N2 to the detector from a commercially available pressurised cylinder located close to the analyser.
X-ray analysis techniques have been used in the laboratory for many years. In order to meet the increasing demand for the measurement of trace sulphur content in oil refineries, DKK began to apply these techniques and produce on-line analysers using Si(Li) detectors. Our clients’ requirements for greater sensitivity and lower detection limits increased but the conventional Si(Li) semiconductor was already at the limits of its performance.
In order to overcome these performance limitations, DKK developed a cooling system for the Si(Li) detector using liquid N2. This simple but extremely effective system employs a 10 litre dewer vessel which is fed with liquid N2. As the liquid N2 is consumed by the detector, it needs to be replenished. This is controlled automatically by the analyser using a level sensor suitable for cryogenic service. The only routine work required by the plant technician is to check the liquid level of the N2 cylinder adjacent to the analyser house on a regular basis. When the cylinder becomes empty, it can be replaced in the same way as compressed gases for other types of on-line analysers are changed (process gas chromatographs for example). If the maintenance technician does not replace the N2cylinder when required, then a diagnostic alarm is tripped. The analyser can still function for 3 more days after this alarm has been generated allowing plenty of time to change the cylinder and keep the analyser on-line.
HSCA analysers are providing excellent performance under field conditions with repeatability's of +/- 1 ppm for 0~20 ppmS ranges. The reliability of the measurement results has allowed our clients to reduce the number of laboratory checks carried out, particularly during night shifts. One client has reported to us that he has been able to reduce the number of cross checks from 17 per month down to 10 per month.
Typical applications for this analyser are process and quality control at hydro desulphurisation plants for kerosene and gas oil.
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