A device for purification of wastewater comprising a foaming agent, said device comprising: (i) an empty air-tight chamber of volume 10 to 100000 litres, capable of withstanding pressure up to 6894757 Pa (1000 psig) comprising: (a) an inlet for admittance of wastewater and even numbered outlets (104 - 106) for exit of foam, where said inlet is operatively connectable with means to stop said admittance when the chamber is filled to the extent of 10 to 50 % of its capacity; (b) a plurality of nozzles inside said chamber to introduce a gas therein under a pressure of 689.5 Pa to 6894757 Pa (0.1 to 1000 psig) and a flow rate of 0.1 to 10000 litres per minute; (ii) at least one foam-breaker comprising a vent for escape of gaseous components of said foam and means for collecting a concentrated form of said foaming agent said means for collecting being a tube that serves as a conduit for flow of the foaming agent which is generated as a result of the action of the foam breaker and a container to collect the concentrated form of said foaming agent; and, (iii) a plurality of tubes (107 - 112) serving as conduits for the foam from each outlet which allow the foam to be conveyed in a radial manner outside the chamber to at least one foam breaker wherein there are as many number of tubes as there are outlets, such that each outlet has a dedicated tube and wherein said tubes are arranged in an axis symmetric manner with respect to the longitudinal axis of the chamber. (i) an empty air-tight chamber of volume 10 to 100000 litres, capable of withstanding pressure up to 6894757 Pa (1000 psig) comprising: (a) an inlet for admittance of wastewater and even numbered outlets (104 - 106) for exit of foam, where said inlet is operatively connectable with means to stop said admittance when the chamber is filled to the extent of 10 to 50 % of its capacity; (b) a plurality of nozzles inside said chamber to introduce a gas therein under a pressure of 689.5 Pa to 6894757 Pa (0.1 to 1000 psig) and a flow rate of 0.1 to 10000 litres per minute; (a) an inlet for admittance of wastewater and even numbered outlets (104 - 106) for exit of foam, where said inlet is operatively connectable with means to stop said admittance when the chamber is filled to the extent of 10 to 50 % of its capacity; (b) a plurality of nozzles inside said chamber to introduce a gas therein under a pressure of 689.5 Pa to 6894757 Pa (0.1 to 1000 psig) and a flow rate of 0.1 to 10000 litres per minute; (ii) at least one foam-breaker comprising a vent for escape of gaseous components of said foam and means for collecting a concentrated form of said foaming agent said means for collecting being a tube that serves as a conduit for flow of the foaming agent which is generated as a result of the action of the foam breaker and a container to collect the concentrated form of said foaming agent; and, (iii) a plurality of tubes (107 - 112) serving as conduits for the foam from each outlet which allow the foam to be conveyed in a radial manner outside the chamber to at least one foam breaker wherein there are as many number of tubes as there are outlets, such that each outlet has a dedicated tube and wherein said tubes are arranged in an axis symmetric manner with respect to the longitudinal axis of the chamber.