Feed nozzle assembly and burner apparatus for gas/liquid reactions

Abstract

A feed nozzle assembly suitable for use in synthesis and combustion reactions involving gas / liquid reaction systems comprises a plurality of nozzles positioned such that their sprays impinge upon one another to obtain improved, or maintain acceptable, drop size, measured as Sauter mean diameter, by suitably balancing impact destruction and coalescence of drops. This feed nozzle assembly can be incorporated into a burner apparatus combining annular areas with stepped extended barriers for feeding oxygen and moderator gas, e.g., steam, all preferably within an exterior annular cooling means such as a water jacket.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to feed nozzles, and more particularly to feed nozzles for a variety of gas / liquid reactions, including chemical synthesis reactions and also combustion and other oxidation reactions in which the feed nozzle is part of a burner apparatus. [0003] 2. Background of the Art [0004] A variety of related industries employ reaction of a gas / liquid system to effect a desired end result. These include, for example, the waste-reduction industry, the chemical manufacturing industry, the gas manufacturing industry, and energy-related industries that rely upon combustion as the energy source. Each of these industries commonly effects this reaction by means of fine atomization of streams of one or more liquids, frequently within a zone of increased temperature. In the case of gasification reactions, both the atomization and the higher temperature serve to promote the liquid-to-gas phase change that improves ...

AI Technical Summary

Benefits of technology

[0011] The invention is a feed means designed to ensure maintenance of appropriate drop size while increasing efficiency of a given operation within a single reactor vessel. In one embodiment it is an improvement in a feed means for a gas / liquid reaction system, in which a feed nozzle assembly includes a plurality of feed nozzles, suitable to atomize at least one liquid feed stream to form sprays, the feed nozzles being positioned such that the sprays impinge upon one another. The result of this impingement is that the Sauter mean diameter of the drops of the impinged sprays is substantially less than, or equal to, the Sauter mean diameter of the drops prior to impingement. The arrangement of the nozzles, which includes selection of an appropriate number of nozzles, can be optimized to ensure desired feed volume within a given time period without unacceptable sacrifice of conversion rate.

Problems solved by technology

If the conversion is decreased, the result will often be residual unreacted liquid feeds which may either form soot or leave the reactor, which may result in undesirable environmental consequences.

This soot can foul equipment, resulting in expensive down-time.

Thus, feed nozzle technology has consistently recognized that, to ensure that drop size remains appropriately small, the aperture of the feed nozzle must remain restricted, which limits the throughput of the nozzle.

This inherent drop size limitation has heretofore limited the efficiency of operations and resulted in use of either multiple parallel reactor vessels, or single reactor vessels with multiple burner nozzles arranged such that the atomized streams do not converge.

This is because those skilled in the art have accepted as common wisdom that convergence of atomized streams tends to result in increased drop size and, therefore, conversion rate losses.

Another problem is encountered where feed nozzles are used as components of so-called “burners”, for example, in the waste-reduction industry.

The combination of the high temperature and the often corrosive nature of the environment surrounding the nozzle, i.e., of the mixture of atomized liquid feed and gases, tends to shorten burner life.

This shortening is due to corrosion and / or thermal fatigue of the metals used to construct the burner and its included nozzle.

Still another problem, encountered by the waste reduction industry in particular, occurs when incompatible liquid feed streams are destined for a single reactor.

Premixing may be impractical in these situations, because the formation of polymeric materials can foul equipment and, in the case of internal mixing burners, even shorten burner life where the polymer / gas reaction results in undesirable products.

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