Claims:1. An atomizer assembly (100) for atomizing liquid hydrocarbon feed, the atomizer assembly (100) comprising:
an inner conduit (102) comprising:
an inlet opening (104) at an upstream end for receiving hydrocarbon feed;
a first segment (106) positioned near the upstream end of the nozzle assembly;
a second segment (110) positioned near the downstream end of the nozzle assembly, the cross section of the first segment (106) being greater than the cross section of the second segment (11-);
an acceleration segment (108) defined between the first segment (106) and the second segment (110), wherein the acceleration segment (108) tapers from the first segment towards the second segment;
an outer conduit (120) enclosing the inner conduit (102), wherein the outer conduit (120) comprises:
a first opening (122) for receiving feed of atomizing steam, the atomizing steam optionally comprising additives selected from Naphtha and Bio-oil;
a second opening (124) for delivering a spray; and
a shredder plate (130) positioned downstream of the outlet opening (112) of the inner conduit (102); and
a dip tube (114) is positioned inside the inner conduit (102), wherein the dip tube (114) comprises:
an inlet port (118) for receiving feed of accelerating steam; and
a plurality of exit holes (116) distributed across its cross section for injecting accelerating steam in the acceleration segment (108) of the inner conduit (102).

2. The atomizer assembly (100) as claimed in claim 1 comprising at least one steam orifice (130) in the annular region (132) between the inner conduit (102) and the outer conduit (120).

3. The atomizer assembly (100) as claimed in claim 1, wherein the shredder plate (130) has a circular cross section.

4. The atomizer assembly (100) as claimed in claim 1, wherein the diameter of the shredder plate (130) is in the in the range of 0.5 to 1.5 times of the diameter of outlet opening of the inner conduit (112).

5. The atomizer assembly (100) as claimed in claim 1, wherein the shredder plate (130) comprises a plurality of grooves (138).

6. The atomizer assembly (100) as claimed in claim 6, wherein the grooves present along the far end of the shredder plate have rectangular shape.

7. The atomizer assembly (100) as claimed in claim 6, wherein the grooves present along the far end of the shredder plate have triangular shape.

8. The atomizer assembly (100) as claimed in claim 1 comprising a mixing zone between the shredder plate 130 and plurality of orifices (136) of the outer conduit (120).

9. The atomizer assembly (100) as claimed in claim 1, wherein the plurality of orifices (124) of the outer conduit (120) are designed to form flat fan spray having spray angle 60°-120°.

10. The atomizer assembly (100) as claimed in claim 1, wherein the inner conduit (102) and the outer conduit (120) have a circular cross section.

11. A fluidized catalytic cracking (FCC) unit for converting high-molecular weight hydrocarbon fractions into high-molecular weight fraction, the fluidized catalytic cracking unit comprising:
an atomizer assembly (100) comprising:
an inner conduit (102) comprising:
an inlet opening (104) at an upstream end for receiving the hydrocarbon feed;
a first segment (106);
a second segment (110); and
an acceleration segment (108), wherein the acceleration segment is positioned between the first segment (106) and the second segment (110), wherein the cross section of the first segment (106) is greater than the cross section of the second segment (110), and wherein the acceleration segment (108) tapers from the first segment (106) towards the second segment (110) of the inner conduit (102);
a dip tube (114) comprising an inlet port (118) for receiving feed of accelerating steam, and a plurality of exit holes (116) distributed across its cross section for injecting accelerating steam in the acceleration segment (108) of the inner conduit (102), wherein the dip tube (114) is positioned inside the inner conduit (102);
an outer conduit (120) enclosing the inner conduit (102), wherein the outer conduit (120) comprises a first opening (122) for receiving feed of atomizing steam, the atomizing steam optionally comprising additives selected from Naphtha and Bio-oil, and a plurality of orifices (128) at the downstream end for delivering the spray; and
a shredder plate (130) positioned downstream of the outlet opening (112) of the inner conduit (102) near the downstream end of the nozzle assembly (100); and
a riser receiving the atomized spray from the atomizing assembly (100) for processing the atomized high-molecular weight hydrocarbon fractions.

12. The fluidized catalytic cracking (FCC) unit as claimed in claim 11, wherein the atomizing assembly (100) is arranged radially in FCC riser

13. The fluidized catalytic cracking (FCC) unit as claimed in claim 11, wherein the atomizing assembly (100) is arranged at elevation in FCC riser.

14. The fluidized catalytic cracking (FCC) unit as claimed in claim 11, wherein the liquid hydrocarbon feed comprises at least one of vacuum gas oil, vacuum residue, atmospheric residue, paraffin extracts, heavy fuel oil, recycled Heavy Cycle Oil (HCO), Naphtha, Bio-Oil and recycled slurry.

15. A method of cracking heavy hydrocarbon fuel by the FCC unit as claimed in claim 11, the method comprising:
receiving the hydrocarbon feed at the inlet opening (104) of the inner conduit (102);
receiving a feed of accelerating steam in the accelerating segment (108) via the dip tube (114);
receiving a feed of atomizing steam at the first opening (122) of the outer conduit (120),
wherein, the atomizing steam comprises an additive selected from naphtha and bio-oil in a range of 0-10 percentage by weight of the atomizing steam; and
delivering a spray of atomized hydrocarbons.
, Description:AS ATTACHED