Principle of foam test procedure

The conditions in batchwise exhaust treatment on a winch beck are simulated. foam test procedure is generated by beating the test solution in a stationary cylinder with a perforated disk attached to a stem. Volume and stability of the foam are determined by measuring the amount immediately after beating and after prolonged standing,  and compared with those of known products. Read more about Foamboard Printing

Equipment

          1000-ml measuring cylinder

          perforated disk (foam plunger)

          water bath

          stopwatch

Ahiba foam beater         (developed in-house )

Test solution
The product to be tested is dissolved in de-ionized water and in water of 10° dH (12.5° Clark). A 2 g/l solution is generally used but a higher or lower concentration can be chosen, depending on the foaming properties of the product.

Procedure
The test is usually carried out at a temperature of 25°C + 2°C. In exceptional cases it can also be performed at higher temperatures.

200 ml test solution is poured into the measuring cylinder, care being taken to avoid foaming. The cylinder contents are foamed by moving the plunger up and down 60 times at an even rate for 1 min. At each stroke the perforated plate is raised from the bottom to about the 1000-ml mark on the cylinder. After 1 min the plunger is taken out.

Assessment
The amount of foam in ml between the top of the liquid column and the upper foam surface is measured immediately, after 1 min, after 5 min and after 10 min. foam test procedure

General

Conventional methods used to determine foaming properties are based primarily on ascertaining the rate of collapse of foam at a given temperature.  (–> FHP 00.10, FHP 00.11, FHP 00.12, FHP 00.14).

By and large these provide useful pointers to the foam-forming or antifoam properties of  surfactants.

Yet they fail to yield practically relevant information regarding antifoams by making too little allowance for a number of  factors with a major impact in application, e.g.

–           behaviour at temperatures > 100°C and under  pressure

–           behaviour at a realistic cycle of temperatures

–           continuous foam generation in circulating liquor systems

–           influence of textile materials

–           influence of processing aids present on the textile

–           uptake or filtering out of antifoam components onto the textile

etc.

The FOAMY HT foam tester,  produced in a joint  project with ZELTEX,  is a further development  of the ” Berendt System”. The new  instrument, which consists of a  ZELTEX  COLORSTAR CS 2 and the ZELTEX  FOAMY foam tester,  enables foaming properties to be studied under closely simulated mill conditions.  The FOAMY  operates on the circulation principle. The liquor is pumped through the textile material and through a spray nozzle with defined holes onto the liquor surface, generating foam. The antifoam can be metered in via a sluice.  Temperature and time conditions are controlled by the integrated PC 1000  microcomputer. The rate of liquor flow is controlled by a microcomputer integrated in the CS2. 

1. Working procedure  
1.1 Introduction   The FOAMY is used in particular to test antifoams such as o  Albegal FFA o  Albegal FFD o  Albatex FFO o  Albatex FFC o  Cibaflow CIR o  Cibaflow JET o  corresponding research formulations o  and competition products.   The procedure is the same for all products: –  charge with textile material and  a foaming medium –  generate foam by circulating liquor through the spray nozzle –  add antifoam –  start the time/temperature program –  note and record the thickness of the foam layer  

See enclosures 1 and 5  for a description and technical  data of the COLOR­STAR CS and the FOAMY respectively. The description of the PC 1000  is given in enclosure 2.

1.2  Required amount of antifoam and composition of foaming medium
    Required amount of antifoam Composition of foaming medium  
  Albegal FFA Cibaflow CIR   10 ml 10% w/v solution Ultravon W h.c.(300%) ammonium sulphate adjusted to pH 4.7 with formic acid 0.15 2.0 g/l g/l
  Albegal FFD 10 ml 10% w/v solution Ultravon W h.c.(300%) ammonium sulphate adjusted to pH 4.7 with formic acid 0.15 2.0 g/l g/l
  Albatex FFO 10 ml 4% w/v solution Ultravon W h.c.(300%) ammonium sulphate adjusted to pH 4.7 with formic acid 0.1 2.0 g/l g/l
  Albatex FFC Cibaflow JET 10 ml 3% w/v solution Ultravon W h.c.(300%) ammonium sulphate adjusted to pH 4.7 with formic acid 0.2 2.0   g/l g/l
1.3 Textile material   38 g cotton/polyester tricot No. 7-4011.    Width of material  =  12.5 cm   The textile material is wound loosely, without tension, on the FOAMY material support  
1.4 Time / temperature program   The tests on the antifoams listed above are all performed under the same time/temperature conditions. The conditions are stored in the  PC 1000 control unit.. Enclosure 3.  
        130°C   5 min. 130°C      
              5°C/min  
                 
      3.5°C/min         90°C
                   
                 
  50°C 50°C            
  10 min.            
                 
1.5 Procedural steps  with the FOAMY

            Keyboard and display of the PC 1000 control unit ( A below)

                        Keyboard                                                                                  Display

    7     8   9   M         000   00   00   00
    4     5   6   S     Temp. Grad. Time Step
    1     2   3   +            
    <      0     >    –            
 

            Keyboard and display of the CS 2 control unit  ( B below)

                          Display               Keyboard
    Liquor flow rate     Full   Rinse     Drain
    Differential pressure       Press   Vacuum  
  Key to activate  the liquor flow  rate control Key to activate the differential pressure control     Const.   Pump  
        +     ON/ OFF   Man.