In this project, a first report on combined novel hybrid technique (hydrodynamic cavitation + hydro gels packed bed adsorption) has been studied for dye degradation and subsequent adsorption of dye molecules. a bench scale hybrid system consists of 5 l of capacity have been fabricated in in-house for carrying out the initial experiments. initially, hydrodynamic cavitation (hc) was employed for the degradation of dye molecules and subsequent adsorption of dye molecules have been carried out by adopting synthesized polymer hydro gels. in hydrodynamic cavitation, mainly cavities are formed due to the pressure variation in the flowing liquid in a pipe caused by a change in flow area by the incorporation of orifice plate in the liquid flow line. the cavities collapse generates a localized ‘‘hot spots’’ is known as called hot spot theory. these hot spots consist of 10,000 k and pressures of about 1000 atm over a microsecond interval. under this extreme conditions water molecules are ability to form or dissociated into h• and •oh radicals. these •oh radicals are then diffuse into the bulk liquid medium where they will react with organic pollutants. even though chances of thermal decomposition of organic pollutants are also occurs in the hydrodynamic cavitation because the generated temperature and pressure through the cavity collapse is sufficient to break the bonds of an organic molecules. hence the larger molecules can be breakdown into smaller molecules. in another hand, polymeric hydro gels play an important role in the treatment of waste water. hydrog els are water-swollen cross linked network of hydrophilic polymers. due to the hydrophilic groups in their backbone, hydro gels can imbibe large quantities of water and swell. in this project, ultrasonic irradiation is used to initiate the emulsion polymerization to form hydro gel through the generation of free radicals as well as the uniform distribution of clay across the hydro gel polymer matrix. recently, some attempts have been made to modify the properties of polymeric hydrogels by the incorporation of nano- or micro-particles of inorganic materials, such as montmorillonite, kaolin, mica, bentonite into the polymer networks. hydro gels loaded with dispersed clays are a new class of composite materials which combine elasticity and permeability of the gels with high ability of the clays to adsorb different substances. many studied reveals the enhancement of adsorption process by combining it with ultrasonic cavitation at lab level. no studies were found as of now on integration of hydrodynamic cavitation and polymer hydro gel packed bed adsorption for the removal organic pollutants from wastewater on bench/pilot sclae. hydrodynamic cavitation combined with packed bed hydro gel process has been developed with the aim of treatment of bulk quantity of wastewater. in this project poly acrylic acid (paa)/nano composite hydro gels which include paa-bentonite clay nano composite hydro gels have been synthesized via ultrasound assisted emulsion polymerization technique. synthesized hydro gels have been characterized by xrd and tem analysis. operational parameters such as effect of inlet pressure, effect of bentonite clay content in paa hydro gel, effect of hydro gel quantity loading in packed bed, effect of ph on removal of dye pollutants have been investigated using hybrid technique. initially the azo type of dyes such as malachite green and crystal violet dye removal have been studied using the bench scale hybrid system. the developed hybrid system has also been tested for the treatment of real industrial textile wastewater to know its effectiveness. it was found that the power consumption for the treatment of dye wastewater at bench scale is around 562 kwh/m3 and the cost per 1 l of dye wastewater treatment were around 3 rupees.