Benefits for the user are
- Fast detection of phase differences (response times of less than 1 s)
- Replacement of manual, visual or indirect detection methods (e.g. time control)
- Improvement in product yield
- Saving energy and material costs
- Optimized system control through online information about the process status
- Increased plant safety through continuous monitoring
The use of state-of-the-art digital signal processing technologies guarantees extremely accurate and interference-free measurement of the absolute sonic velocity and concentration of various media in the phase separation. In addition, integrated temperature sensors, the sophisticated sensor design and know-how gained from countless series of measurements and many applications ensure a highly reliable system with a long service life.
The advantages of the measuring method are
- absolute sonic velocity as a clear and traceable physical quantity
- Independent of the color, conductivity and transparency of the process liquid
- Installation directly in pipes and containers
- Robust sensor construction in a completely metallic design without seals or moving parts
- maintenance-free
- Corrosion resistance through the use of special materials
- Use at temperatures up to 200 °C
- High, drift-free measuring accuracy even with high gas bubble content
- Connection of up to four sensors per controller
- Transmission of measurement results via fieldbus (Profi bus DP, Modbus), analog outputs, serial interface or Ethernet
The exact detection of different phases in a pipeline is necessary in various industrial sectors. The different products are often conveyed through the same pipe, but are each fed to a different location.
In applications where, for example, product A is pushed out by product B, the intermediate phase must be separated separately. In breweries, for example, different types of beer are bottled one after the other, but the pre- and post-runs are circulated out and fed back into the brewing process.
Safety aspects also play a role in applications with a high risk potential. In particular, monitoring phase separation in multi-component pipelines in the chemical industry not only provides information on product quality (incoming goods), but also prevents incorrect filling of the storage tanks and thus serious accidents.
In the petrochemical industry, different fuels are conveyed over very long distances in just one pipeline. Here, both the rapid detection of the different products and their quality monitoring are paramount.
The separation of two phases can be carried out in batch processes. Here, the liquids (e.g. water and oil) separate from each other based on their physical and chemical properties.
Application example 1: Organics
During the manufacturing process of cosmetics, a phase separation occurs in which a saline phase containing a lot of water is separated from a preliminary product. This water-rich, lower phase is discharged via the wastewater treatment plant, where the water is treated. The precursor produced, the upper phase, is only biodegradable to a limited extent. It is therefore of the utmost importance to prevent this water-polluting material from entering the wastewater. In order not to pollute the water in the wastewater treatment plants, the immediate and reliable identification of the pre-product phase is of the highest priority in order to prevent it from being fed into the wastewater system by quickly shutting it down.
Optical measuring methods cannot be used at this point because different colorations can occur during phase separation. Furthermore, phase separation can lead to the formation of a mulch layer, which is known to be critical for measurement via optical boundary effects due to contamination effects.
Application example 2: Biodiesel / glycerine
Glycerine is a by-product of biodiesel production. The mixture of both substances is conveyed in large settling tanks and then has several hours to separate. The LiquiSonic® sensors are usually installed in the outlet of the tank. By detecting the respective phase, the valve is activated and the biodiesel and glycerine are fed to the respective further processing. The intermediate phase returns to the separation process.
1.3 Phase separation in the continuous process
In a continuous process, the separation of a process flow is controlled via one or more sensors. In this case, only the sonic velocity value characteristic of the respective phase is monitored and kept constant.
The product concentration of the carrier phase in the feed often fluctuates. This quickly shifts the height of the phase boundary. As a result, the carrier phase could be drawn off with the product, which has a major impact on purity. In terms of process technology, the liquids are separated via a pump in each of the two outlet lines. In this way, for example, the continuous separation of a reaction mixture can be controlled.
The advantages of the LiquiSonic® measuring technology lie not only in the extremely fast response time of less than 1s, but also in the connection of up to four sensors to just one LiquiSonic® controller. This processes all measured values and forwards the data to the higher-level control system.
Depending on the tank type and requirements, different installation variants are possible, which are shown in the diagram below.
Installation variant 1
The sensors are most frequently installed on the side of the container. The requirement for the middle sensor (measuring point 2) depends on the application and the characteristics of the intermediate phase.
Installation variant 2
If only one sensor with a length of up to 4 m is used, the phase profile of the entire tank can be determined. By mounting the sensor on a movable carriage, for example, and in combination with a displacement meter, the phase limits can be determined exactly at their current height.
Installation variants 3 and 4
In tanks in which no connections are available on the side or can be realized subsequently, e.g. heatable double jacket, the sensors are positioned directly or via immersion tubes at the correct location. When using immersion tubes, the sensor electronics are located remotely at a distance of up to 15 m outside the tank.
2. LiquiSonic® system
2.1 LiquiSonic® 30
The LiquiSonic® system consists of one or more sensors and a controller. The ultrasonic sensor contains the ultrasonic measuring section and the high-precision temperature measurement. Each sensor works independently and can be operated in different applications. The parts of the sensor that come into contact with liquids are made of stainless steel DIN 1.4571 as standard.
The robust and fully encapsulated design requires no seals or "windows" for use and is therefore completely maintenance-free. Various additional functions integrated into the sensor, such as the flow monitor and wet/dry monitoring, significantly increase customer benefits. The LiquiSonic® high-performance technology ensures stable measurement results, even with increased gas bubble content and strong signal attenuation by the process liquid.
The special sensor electronics are located in a closed die-cast housing with protection class IP65. If space is limited, sensors with remote electronics can be installed. The Controller 30 manages the measurement data and handles the visualization. It is operated via the high-resolution touch display. Thanks to the secure network integration including web server, the controller can alternatively be operated via a browser using a PC or tablet.
The display value can be adjusted to internal reference values using the adjustment function. The process data is updated every 250 milliseconds. If the measured values move outside the limit range, this is shown on the display and a signal is given immediately.
The measurement data can be transmitted to controllers, process control systems or PCs via several freely scalable analogue or relay outputs as well as via various fieldbus interfaces. The measurement data is stored in the comprehensive data logbook. There are 2 GB available for process information and 32 (optionally 99) product data records for various process liquids. These can be read out via network or USB interface for processing on a PC. In addition, process logs can be easily created for documentation purposes. An event logbook is also integrated in the Controller 30. This documents events such as a manual product change, configuration changes or warning and status messages.
2.2 Accessories
2.2.1 Controller and field housing
The controller is designed for installation in control panels. Alternatively, a 19" 3U housing is available. To use the controller in the field, field housings made of plastic or stainless steel are available.
2.2.2 Field bus
The fieldbus option offers the possibility to integrate the controller into a process control system or to automate the process sequence using a controller (PLC). In addition to the transmission of measured values such as concentration or temperature, parameters and control data (e.g. product changeover) can also be exchanged.
The controller supports various fieldbus systems and follows the standards recommended by the respective standardization organizations. Common variants are Modbus and Profibus DP.
3. Quality and service
Enthusiasm for technological progress is our driving force to help shape the market of tomorrow. You, our customers, are at the center of this. We are committed to providing you with top performance. In close cooperation with you, we pursue the path of innovation - by developing the right answer to your demanding measuring task or by carrying out individual system adaptations. The increasing complexity of application-specific requirements makes a comprehensive understanding of interrelationships and interactions essential.
Creative research is another key pillar of our company. The specialists in our research and development team make valuable contributions to the optimization of product properties - such as testing new sensor designs and materials or the sophisticated functionality of electronics, hardware and software components. Our SensoTech quality management also only accepts top performance in production. We have been ISO 9001 certified since 1995. All device components undergo a variety of test procedures in the various production stages; the systems are already subjected to a burn-in procedure in our company. Our maxim: maximum functionality, resilience and safety.
All this is only possible thanks to the commitment and pronounced quality awareness of our employees. We owe our success to their outstanding expertise and motivation. Together, with passion and conviction, we work with a level of excellence that is second to none.
We cultivate relationships with our customers. As our devices are maintenance-free, we can focus entirely on your concerns when it comes to service and actively support you with professional advice, convenient in-house installation and customer training. During the design phase, we analyze your situation directly on site and carry out test measurements if necessary. Our measuring devices are capable of achieving maximum accuracy and reliability even under unfavorable conditions. Even after installation: we are there for you, our response times are short - thanks to remote access options specifically tailored to your needs.
As part of our international cooperation, we form a globally networked team for our customers, which ensures optimum advice and service across national borders. We therefore attach great importance to effective knowledge and qualification management. Our numerous international representatives in all major geographical markets around the world can draw on the expert knowledge within the company and continuously update their skills in application- and practice-related training programs. Proximity to customers around the globe: a key factor in our successful global presence, alongside our extensive industry experience.
Innovative sensor technology
SensoTech is the specialist for the analysis and optimization of process engineering processes in liquids. Since our foundation in 1990, we have developed into the leading company for measuring devices for the inline determination of concentrations in liquids. Our analysis systems set the trend - worldwide.
Innovative engineering made in Germany, based on the principle of measuring the absolute speed of sound during the process. A method that we have perfected into a highly precise and exceptionally user-friendly sensor technology.
In addition to concentration and density measurement, typical applications include phase detection or the monitoring of complex reactions such as polymerization and crystallization. Our LiquiSonic® measuring and analysis systems ensure optimum product quality, maximum plant safety or reduce costs through efficient resource management in a wide range of industries, such as the chemical and pharmaceutical industry, steel industry, food technology, mechanical and plant engineering, automotive engineering and others.
We want you to fully exploit the potential of your production facilities at all times. SensoTech systems deliver highly accurate, precise and reproducible measurement results, even under difficult process conditions. And all this inline and without safety-critical sampling, immediately available for your automation system. All system parameters can also be adjusted using powerful configuration tools so that you can react immediately and easily to changes.
We offer excellent, sophisticated technology to improve your manufacturing processes and are your partner for demanding, often unexpected solutions in your industry, for your applications - however specific they may be. When it comes to liquids, we set the standards.
LiquiSonic® is an inline analysis system that determines the concentration or density of liquids or media directly in the process without delay. The device is based on the high-precision measurement of the absolute sonic velocity and process temperature and thus allows the detection of phase differences.
