Depending on the type, the raw materials are mixed in the desired ratio and converted into water glass in the alkali silicate synthesis. Since impurities negatively affect the melting process and product properties, raw materials of high purity are used.
The LiquiSonic® Measurement technology offers an exact and rapid determination of process concentrations (Na2O or K2O and SiO2) as well as the process temperature. Through continuous data recording, the process conditions can be monitored as part of quality control, even at a later date.
Sound velocity measurement with LiquiSonic® 40
Application
Water glass is made by melting highly purified quartz sand (SiO2) with alkali carbonate (Na2CO3 or K2CO3) is produced. The raw material mixture is continuously melted in a melting tank at 1200 °C to 1500 °C. The molten alkali silicate is cooled on a conveyor belt by spraying with water. The cooled fragments are dissolved in an autoclave at 4 - 5 bar and 140 - 150 °C until the desired density and viscosity are reached.
Final impurities are removed by filtration. The filtered clear alkali silicate solution is then adjusted to the desired moisture content with water. LiquiSonic® Sensors determine process concentrations around the clock and enable precise process control. This prevents quality fluctuations.
Installation
The LiquiSonic® Immersion sensors are installed directly into the bypass pipeline of the autoclave. The robust sensor construction and the choice of special materials, such as HC2000, ensure long process uptime of the system. The LiquiSonic® Controller 40 is connected with the LiquiSonic® Sensor as well as the measuring unit for the second physical quantity. The controller displays the concentration of Na in the main menu2O and SiO2 as well as the current process temperature.
Typical measurement ranges:
Concentration range Na2O: 6 to 9 m%
Concentration range SiO2: 20 to 30 m%
Temperature range: 40 to 95 °C
Concentration range K2O: 19 to 24 m%
Concentration range SiO2: 30 to 35 m%
Temperature range: 40 to 70 °C
Customer benefits
LiquiSonic® ensures precise concentration measurement and adjustment of the required Na2O/SiO2 molar ratio. This allows properties such as stability against stress to be optimally induced. LiquiSonic® reduces time-consuming and complex laboratory measurements, such as potentiometric titration:
- Time required: 1 h per day
The optimal dissolution rate of the water glass fragments saves steam.
In the production of water glass, various alkali carbonates are used in addition to quartz sand. Thus, by using soda (Na2CO3) soda water glass and by potash (K2CO3) potash water glass is produced.
