Method and device for the continuous determination of the dynamic surface tension according to the principle of the drop weight method

摘要

In a number of industrial processes in different areas of process water play an important role. In areas such as waste water treatment or natural body of water is the knowledge of the properties of the water also of great importance. bulk properties, such as ph - value, conductivity, temperature, inter alia, are measured, but not necessarily the sufficient knowledge about the properties of the water. A further, as yet still underestimated parameter is the surface tension of the corresponding water. It is known as a size, but is on the basis of the current measuring art offer sufficient used not yet practicable. The plurality of measuring techniques used operate discontinuously and also require a certain number of personnel. Processes are subject to a time-dependent changes and thus, a discontinuous measurement of only a limited extent for characterization of the process can be used. Tests for the continuous measurement of the surface tension are predominantly based on the method of the maximum bubbles pressure.It was therefore the object of the present invention to develop a method of the relatively simple measurement method makes use of the drop weight, in order to the surface tension of continuously over a very long period (hours and days) to be measured and this with a very robust measuring structure. Main problem in this connection was the exact and continuous supply of the measurement fluid to a defined drip surface is disposed for the production of drops, the characteristic of the biologically times to the point in time present surface tension are. $\sigma \; =\; v\; ·\; p\; ·\; g\; /\; 2\pi \; ·\; r$_Chapter·fσ = surface tension [mn / m]V = drop volume [cm³]ρ = density [g / cm³)g = gravitational acceleration [cm / s²]r_Chapter = Radius of the hydrophilic drip surface is disposed [cm]f = correction factor