Reuse of Salt-Containing Dyeing Effluents by Means …
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Also, in order to ensure industrial robustness, the system is equipped with several
instruments to ensure that the effluent characteristics are within the system operative
constraints.
The effluent is separated into three tanks, each one with UV lamps and a stirring
device to homogenise the effluent. The last one is equipped with elements to prepare
the effluent before being reused.
After the first step of electrochemical treatment is completed, colour of treated
effluent is measured. If the effluent meets the established criteria acceptance, it is
directed to tank 3 where the reconstitution step is carried out in order to prepare the
effluent to be reused in new dyeing processes.
This approach gives an expanded process which is depicted in Fig. 6 for a system
consisting of “n” treatment tanks.
From the equipment point of view, the functional steps are divided into five subprocesses:
1. Analysis of water conditions: During this step, the input valve is opened in order
to fill the three treatment tanks passing through a filtre. This filtre will prevent
damage or malfunction of the system due to fibres, yarns or solids in suspension
that would eventually damage the electrochemical cell and hydraulic elements.
The following parameters can be checked in this point to evaluate the suitability
of the effluent to be treated: pH, conductivity and temperature. During this
operation, the effluent should not go through the electrochemical cell till it is
Fig. 6 Schema of the EC-UV system with n treatment tanks
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Also, in order to ensure industrial robustness, the system is equipped with several
instruments to ensure that the effluent characteristics are within the system operative
constraints.
The effluent is separated into three tanks, each one with UV lamps and a stirring
device to homogenise the effluent. The last one is equipped with elements to prepare
the effluent before being reused.
After the first step of electrochemical treatment is completed, colour of treated
effluent is measured. If the effluent meets the established criteria acceptance, it is
directed to tank 3 where the reconstitution step is carried out in order to prepare the
effluent to be reused in new dyeing processes.
This approach gives an expanded process which is depicted in Fig. 6 for a system
consisting of “n” treatment tanks.
From the equipment point of view, the functional steps are divided into five subprocesses:
1. Analysis of water conditions: During this step, the input valve is opened in order
to fill the three treatment tanks passing through a filtre. This filtre will prevent
damage or malfunction of the system due to fibres, yarns or solids in suspension
that would eventually damage the electrochemical cell and hydraulic elements.
The following parameters can be checked in this point to evaluate the suitability
of the effluent to be treated: pH, conductivity and temperature. During this
operation, the effluent should not go through the electrochemical cell till it is
Fig. 6 Schema of the EC-UV system with n treatment tanks