CATALYTIC CRACKING SYSTEM COMPRISING SPRAY NOZZLE ASSEMBLY WITH LIQUID INLET EXTENSION AND ATOMISER Russian patent published in 2019 - IPC B05B7/04 

FIELD: spraying; pulverisation.

SUBSTANCE: invention relates to spray nozzles for liquids in catalytic cracking systems, in particular, adapted for atomising and spraying liquids supplied to a fluidised catalytic cracking riser reactor. Catalytic cracking system comprises a riser, liquid spray nozzle assembly (10) located in wall (11) of riser to release the atomised liquid hydrocarbon into the riser. Spray nozzle assembly (10) comprises elongated nozzle housing (17) which forms mixing zone (20) and expansion zone (24) of an elongated cylinder located downstream of mixing zone (20) and communicating therewith and passing through wall (11) of the riser. Assembly (10) also comprises liquid hydrocarbon inlet (21), steam inlet (22) and spray tip (25). Liquid hydrocarbon inlet (21) is located in elongated nozzle body (17), through which a jet of liquid hydrocarbon under pressure is directed into said mixing zone (20). Steam inlet (22) is installed at the upstream axial end of elongated nozzle body (17), through which the pressurised steam flow is directed to said mixing zone (20) along central axis (59) of mixing zone (20) to atomise the liquid hydrocarbon, directed to mixing zone (20). Spray tip (25) is mounted at the downstream end of expansion zone (24) of the cylinder and has an outlet opening (26) through which the atomised liquid hydrocarbon is released in a predetermined spray pattern. Liquid hydrocarbon inlet (21) includes protrusion (55) of the liquid hydrocarbon inlet extension and atomiser installed in the side wall of elongated nozzle body (17) and extending into mixing zone (20) transversely relative to central axis (59) of mixing zone (20). Protrusion (55) of the liquid hydrocarbon inlet extension and the atomiser has passage (56) of the liquid hydrocarbon extension and a plurality of outlets (58) at the downstream end of passage (56) liquid hydrocarbon extension. Protrusion (55) of the liquid hydrocarbon inlet extension and the atomiser has closed downstream tip (65) which forms flat impingement surface (66) substantially on the central axis of mixing zone (20). Outlets (58) of protrusion (55) of the liquid hydrocarbon inlet extension and the atomiser are formed by a pair of transverse channels extending through diametrically opposite sides of protrusion (55) of the liquid hydrocarbon inlet extension and the atomiser, ensuring communication with passage (56) of the liquid hydrocarbon extension. Each of the transverse channels has side (68) coplanar with flat impingement surface (66) in such a way that it is possible to direct the liquid hydrocarbon with outlets (58) from flat impingement surface (66) to mixing zone (20) in the form of a pair of flat fan-shaped structures in the transverse direction relative to the central axis of mixing zone (20) and on the centre of the transverse steam flow from steam inlet (22).

EFFECT: technical result of the invention is to improve the performance of spraying liquid in catalytic cracking reactors, improving reliability and ease of operation.

6 cl, 3 dwg