Energy saving fuel oil atomizer

A method for introducing atomized liquid fuel through a nozzle having a plurality of discharge ports into a furnace for combustion therein, the method comprising the steps of:

• providing first and second, separated chambers interiorly of the nozzle;
• flowing a core stream of a pressurized gaseous medium including steam from the first chamber along an axis inclined relative to a longitudinal axis of the nozzle to the ports;
• flowing liquid fuel from the second chamber towards each core stream and substantially equally dividing the flow of liquid fuel into a number of fuel branch flow equalling the number of core streams;
• directing each branch flow generally tangentially to the associated core stream into contact with the core stream so as to form a substantially homogenous, annular fuel stream surrounding the core stream;
• forming a secondary, annular stream of the medium for each core stream at a point downstream of the point at which the fuel stream is combined with the core stream;
• enveloping the combined core and fuel streams with the secondary stream;
• equalizing the pressure of the combined core and fuel streams and of the secondary stream at about the point where the latter envelops the former;
• and discharging each core stream and the associated, coaxial fuel and secondary streams from the corresponding ports into the furnace for combustion therein.

A nozzle for atomizing liquid fuel preparatory to its combustion in a furnace, the nozzle comprising:

• a generally axially oriented housing defining first and second, separated chambers;
• a discharge conduit in fluid communication with the first chamber and extending through the housing to the exterior thereof;
• the conduit having first, second and third axially aligned and spaced apart sections of successively large cross-sectional dimensions arranged successively from the first chamber through the housing to the exterior thereof and terminating in a discharge port at an end of the third section;
• first passage means defined by the housing communicating the first chamber with an upstream end of the third conduit section;
• second passage means fluidly communicating the second chamber with an upstream end of the second section and including at least two apertures disposed tangentially to the periphery of the first section;
• whereby the introduction of a pressurized gas in the first chamber and the introduction of a pressurized liquid fuel into the second chamber causes the formation of a gas-fuel mixture in the third conduit section comprised of a primary gaseous core stream, an annular fuel comprised of a primary gaseous core stream, an annular fuel stream surrounding the core stream, and a secondary gaseous stream enveloping the fuel stream;
• and whereby further the gaseous streams cause the atomization of the liquid fuel and protect housing walls defining the conduit and in the vicinity of the port from direct contact with the fuel and thereby also prevent a deposition of fuel particles on the walls.

A nozzle for introducing atomized liquid fuel into a furnace for combustion therein, the nozzle comprising:

• an inner member defining a fuel compartment, a housing surrounding the inner member and defining in conjunction with the inner member a chamber;
• a conduit extending from the chamber to an exterior of the housing and forming axially aligned and successively spaced first, second and third conduit sections, the first section communicating with the chamber and the third section terminating in a discharge port at an outer surface of the housing, the first, second and third sections having consecutively larger diameters;
• a first passage fluidly communicating the compartment with a wall defining an upstream end of the second conduit section, the wall including a plurality of circumferentially spaced apart apertures oriented generally tangentially with respect to the second conduit section;
• whereby the application of pressurized liquid fuel to the compartment and of pressurized gas to the chamber forms a gas core stream flowing through the sections and an annular liquid fuel stream surrounding the core stream and flowing through the second and third conduit sections, the core and fuel streams forming a combined stream;
• and whereby further the introduction of liquid fuel through the apertures into the second conduit section causes an atomization of liquid fuel so that the annular fuel stream comprises atomized liquid fuel;
• second passage means communicating with the chamber;
• tubular wall means downstream of the wall, surrounding the combined stream, spaced from the housing and defining with the housing an annular space in communication with the second passage means, oriented parallel and coaxial to the conduit, and terminating at and communicating with an upstream end of the third conduit section;
• whereby pressurized gas from the chamber flows through the second passage means and the annular space to form an annular, secondary gas stream enveloping the combined stream;
• and whereby further the combined stream and the annular stream are simultaneously discharged from the port, the discharged liquid fuel being atomized, and direct contact between the liquid fuel and the housing is prevented to thereby enhance the combustion of the liquid fuel and prevent an accumulation of fuel particles on the nozzle.

A nozzle for introducing atomized liquid fuel into a furnace for combustion therein, the nozzle comprising an inner member defining a chamber for connection to a source of a pressurized, gaseous medium, a shell in surrounding relationship disposed about the member, the shell defining a compartment and including means for supplying liquid fuel to the compartment;

• a discharge conduit extending through the member and the shell and communicating the chamber with a port at an exterior of the shell so as to flow a core stream of the medium in the conduit;
• an insert disposed between the member and the shell, the insert having a first wall spaced apart from the shell and defining a first passage in communication with the compartment and the conduit at a first point intermediate the chamber and the port and arranged so as to flow the liquid fuel annularly about the core stream flowing from the chamber through the conduit;
• the insert having a second wall spaced apart from the member and defining a second passage communicating the chamber with the conduit at a second point disposed between the first point and the port and arranged so as to flow gaseous medium generally annularly about the liquid fuel flowing in the conduit between the first point and the port;
• the insert defining a first section of the conduit intermediate the member and the shell and having a diameter larger than the portion of the conduit through the member;
• the first passage having a lateral extent in a direction transverse to the axis of and larger than the diameter of the first conduit section;
• whereby an atomized liquid fuel stream of a generally annular cross-section issues from the conduit and the core stream and an annular exterior stream of gaseous medium prevents fuel from contacting portions of the shell defining the conduit and the port.