An assembly for atomization of a hydrocarbon feedstock, the assembly comprising: an inner conduit for receiving and mixing the hydrocarbon feedstock with a diluent mixed steam to produce an emulsion, the inner conduit comprising: a first inlet for feeding the hydrocarbon feedstock to the inner conduit; and a second inlet for feeding the diluent mixed steam to the inner conduit, wherein the flow of the diluent mixed steam is in a motion opposing that of the hydrocarbon feedstock; an impingement section for atomization of the hydrocarbon feedstock, the impingement section comprising: a serrated wedge shaped guiding edge aligned axially at an exit end of the inner conduit in an inverted manner; and a plurality of conical plates, each bearing a plurality of orifices, disposed on either side of rim of the guiding edge; wherein the impingement section is to form an emulsion film on at least a portion of the conical of the conical plates on impact of the emulsion against the guiding edge; an outer conduit positioned concentrically above the inner conduit, the outer conduit comprising: a steam inlet for feeding atomizing steam, wherein the atomizing steam is passed through a space between outer walls of inner conduit and the outer conduit; and a plurality of jet tubes oriented towards the inner conduit at a certain angle from a nozzle exit, the jet tubes comprising jet orifices to inject streams of atomizing steam onto each of the plurality of the conical plates to cause partial atomization of the hydrocarbon feedstock in the emulsion film and to disperse a plurality of droplets from each of the plurality of orifices disposed on the plurality of conical plates; and a nozzle exit aligned axially to the impingement section to transmit the plurality of droplets to a reactor. an inner conduit for receiving and mixing the hydrocarbon feedstock with a diluent mixed steam to produce an emulsion, the inner conduit comprising: a first inlet for feeding the hydrocarbon feedstock to the inner conduit; and a second inlet for feeding the diluent mixed steam to the inner conduit, wherein the flow of the diluent mixed steam is in a motion opposing that of the hydrocarbon feedstock; a first inlet for feeding the hydrocarbon feedstock to the inner conduit; and a second inlet for feeding the diluent mixed steam to the inner conduit, wherein the flow of the diluent mixed steam is in a motion opposing that of the hydrocarbon feedstock; an impingement section for atomization of the hydrocarbon feedstock, the impingement section comprising: a serrated wedge shaped guiding edge aligned axially at an exit end of the inner conduit in an inverted manner; and a plurality of conical plates, each bearing a plurality of orifices, disposed on either side of rim of the guiding edge; wherein the impingement section is to form an emulsion film on at least a portion of the conical of the conical plates on impact of the emulsion against the guiding edge; a serrated wedge shaped guiding edge aligned axially at an exit end of the inner conduit in an inverted manner; and a plurality of conical plates, each bearing a plurality of orifices, disposed on either side of rim of the guiding edge; wherein the impingement section is to form an emulsion film on at least a portion of the conical of the conical plates on impact of the emulsion against the guiding edge; an outer conduit positioned concentrically above the inner conduit, the outer conduit comprising: a steam inlet for feeding atomizing steam, wherein the atomizing steam is passed through a space between outer walls of inner conduit and the outer conduit; and a plurality of jet tubes oriented towards the inner conduit at a certain angle from a nozzle exit, the jet tubes comprising jet orifices to inject streams of atomizing steam onto each of the plurality of the conical plates to cause partial atomization of the hydrocarbon feedstock in the emulsion film and to disperse a plurality of droplets from each of the plurality of orifices disposed on the plurality of conical plates; and a nozzle exit aligned axially to the impingement section to transmit the plurality of droplets to a reactor. a steam inlet for feeding atomizing steam, wherein the atomizing steam is passed through a space between outer walls of inner conduit and the outer conduit; and a plurality of jet tubes oriented towards the inner conduit at a certain angle from a nozzle exit, the jet tubes comprising jet orifices to inject streams of atomizing steam onto each of the plurality of the conical plates to cause partial atomization of the hydrocarbon feedstock in the emulsion film and to disperse a plurality of droplets from each of the plurality of orifices disposed on the plurality of conical plates; and a nozzle exit aligned axially to the impingement section to transmit the plurality of droplets to a reactor.