SPINBATH CIRCULATION

Features

1. Constant and stable supply of the spinning machine 
   with degassed and filtered spinbath with 
   the proper composition and at the correct temperature
2. Avoids depositing ZnS in the spinbath filter due to degassing
3. Minimisation of energy consumption by employing direct feed of the spinning machine
4. High recovery rates due to minimum gas flow rates with high gas concentrations
5. Pump failure does not interrupt the spinning process

In Detail

The spinbath flows from the filter boxes of one side of the spinning machine down to the bottom degassing tank by gravity. The level in this tank will be the same as is in the bottom tanks due to the common spinbath circulation pipeline, which compensates for possible fluctuations in the flow rates.

From the degasser the spinbath flows under vacuum into the degassing return tank, which is necessary for the vacuum sealing of the degasser. Degassed spinbath flows from this tank towards the common spinbath circulation pipeline and is then pumped to the spinbath filters, and then to the filtration return tank, from where the evaporator and the crystalliser are fed.

The residual spinbath (filtration flow minus evaporator feed) overflows to the mixing tank, in which all the spinbath returning from filtration, evaporation, and crystallisation is mixed. The required sulphuric acid and zinc concentration is controlled by means of an automatic titration analyser and a fully automatic dosing station for sulphuric acid and zinc solution. The spinbath overflows the mixing tank to the common spinbath circulation pipeline and the flows to the bottom tanks. The spinbath bottom tanks are operated in series for higher efficiency. Finally the spinbath is pumped back to the spinning machine.