Multi-purpose, multi-oxy-fuel, power burner/injector/oxygen lance device

Abstract

A multi-purpose, multi-oxy-fuel High Temperature Power Burner / Injector / Oxygen Lance, Mechanical System Apparatus Device, for steelmaking from recycled scrap and / or virgin ferrous charge, which can be employed in multi-oxy-fuel (natural gas; pulverized carbonaceous matter; heavy oil), especially by Oxygen Combusted mixture of Natural Gas / Pulverized Carbonaceous Matter in High Temperature Power Burner Mode, for efficient and rapid melting of solid ferrous charge (cold or preheated) in a special steelmaking Metallurgical Furnace or Open Hearth Furnace, Tandem Furnace, BOF, EAF, as its augmenting or only source of thermal energy; more than one Device in Oxygen-Natural Gas / Pulverized Carbonaceous Matter Power Burner Mode, can be employed as the only source of thermal energy in a modified, originally Electric Arc Furnace, as total replacement of Graphite Electrodes and Electric Arc System, the replacement being noticeably more primary energy efficient than the thermal energy provided by Graphite Electrode / Arc System; it also can be employed in an Solid Particles Injector Mode, for injecting of adequately granulated carbonaceous materials or lime into the molten steel for its carburizing or for foamy slag control; further it can be employed in a natural gas shrouded, pulsating oxygen stream, for vertically to the charge oriented soft blow supersonic Oxygen Injection Lance Mode, for decarburization of the molten metal contained in the hearth of the metallurgical furnace and foamy slag control; in one of the embodiments-generally arcuate-pivotally mounted, liquid media cooled composite body, is pivoted into and out of a furnace vessel through a small opening in the shell wall for auto-regulated constant optimal positioning of the Composite Body Tip against solid or molten charge, in each and all multi-purpose modes; furthermore, when inserted into the furnace vessel, the arcuate composite body can be rotated about its longitudinal axis for directing the oxy-fuel high temperature flame towards unmolten charge in the furnace; in an other-generally linear-embodiment, the liquid cooled composite body is attached to the mast type carrier allowing vertical movement of the composite body which enters the furnace vessel through a small opening in the furnace roof; the bimetallic, liquid cooled special tip assembly of both-arcuate and linear embodiments-of the composite body includes easy replaceable, independent, multi-opening nozzles, mounted in a protective, retracted position inside of the liquid cooled special tip assembly.

Description

[0001] I. Field of the Invention[0002] This invention relates to a multi-purpose, multi-oxy-fuel (natural gas; pulverized carbonaceous matter--hereinafter "coal"; heavy oil) High Temperature Power Burner / solid materials (coal; lime) Injector / supersonic Oxygen Lance shrouded with combustible gas umbrella, with versatile positioning ability Device, for metallurgical furnaces making steel from solid recycled and / or virgin ferrous charge, for delivering into the interior of a metallurgical furnace high temperature thermal energy for efficient and rapid melting of solid recycled or virgin ferrous charge, when in oxy-fuel burner mode and when burning mixture of natural gas / pulverized coal with gaseous oxygen; furthermore, and in particular more than one Device, in multi-oxy-fuel, when burning mixture Natural Gas / Pulverized Coal in High Temperature Burner mode, can be employed for providing modified Electric Arc Furnace (EAF) with thermal energy as its singular and only source and acting a...

AI Technical Summary

Benefits of technology

[0048] It is another object of this invention to provide a Metallurgical Furnace with a Mechanical System Apparatus device comprising a multi-oxy-fuel High Temperature Power Burner / Injector / Oxygen Lance as replacement of the electric energy supplying system and components and at the same time drastically improve efficiency of utilization of the primary energy contained in fossil fuels, and--for example--by being capable of burning a mixture of pulverized coal (approx. 80%) and natural gas (approx. 20%) with oxidant being VPSA oxygen, which will have approximately three (3) times better utilization of energy contained in natural gas or pulverized coal and approximately three (3) times less generation of harmful gases in particular CO.sub.2 and CO.

[0091] Capability to provide improved heat transfer from the torches of the mobile Multi-Ox-Fuel High Temperature Power Burners of the Devices in comparison with the heat transfer from the torches of the stationary ox-fuel burners;

Problems solved by technology

Be that as it may, Electric Arc Furnace steelmaking process is an pyrometallurgical process, which with sizeable air infiltration generates complex and harmful emissions through its inherited operating combustion characteristics.

Furthermore, Electric Arc Furnaces using only electric arc as the only source of thermal energy, are with respect to the utilization of the primary energy, very inefficient.

Current state of the art of the convential Electric Arc Furnace apparatus and operating practices generate substantial emissions in the form of dust and hot fumes.

Carbon monoxide CO, resulting from incomplete oxidation of carbon is a poisonous gas.

It is also believed, it supports depletion of ozone layer around our planet, causing increased occurrence of skin carcinoma.

However, compliance with such demands would result in large investment costs with consequent increase of the cost of produced steel.

Currently, the conflict between ideals of environmentalists and industry in developed countries is growing rapidly.

Furthermore, air pollution originating by the virtue from metallurgical processes of iron and steelmaking, and increased by energy inefficient processes may have very grave consequences which at present are even hard to foretell.

Distress signals have already appeared of dangers that await mankind if urgent measures are not taken to protect the environment against pollution and energy inefficient processes.

Waste smokes and gases formed by industrial processes have become a problem of vital importance;

overall prime energy inefficiency of currently operated processes and systems.

Energy cost crisis which began not so long ago in North America is making existing situation even worse, threatening to spread world wide.

When considering energy utilization efficiency, noticeably aggravating is the fact, that more than 50% of the currently operating ferro-metallurgical industrial processes, consuming massive quantities of electric energy--of which at least a half is generated by burning large quantities of fossil fuel--are extremely inefficient in relation to the primary energy.

In that respect, conventional Electric Arc Furnace steelmaking from cold scrap is exceptionally inefficient: Cumulative thermal efficiency of the thermal energy produced in an Electric Arc Furnace represents only 16-18% of the 100% of primary energy contained in the fossil fuel, burned in the steam producing boiler to propel the turbine and electricity generating electric alternator.

This is already done, regretfully it is not yet exploited to its full potential.

Electric energy used for creating high heat source of thermal energy via electric arc is not the best or only form or type of energy to be used for melting recycled steel scrap and producing new steel.

Electric energy used via electric arc for creating high temperature heat source for melting in Electric Arc Furnace is extremely inefficient with respect to the primary energy; this is valid especially when electricity is generated via burning of the coal in the boiler, producing the steam for the turbine.

However, present day situation in availability and cost of electric energy has drastically changed, not ever to return back.

In majority of developed countries, the electric energy is not available and with price deregulation it is too expensive to be used for profitable steelmaking.

On the other hand, the main obstacle to the introduction of the more primary energy efficient high temperature sources for steelmaking from scrap is the fact, that all so far known steelmaking processes using primarily fossil fuel such as natural gas and oil as substitute, required a completely new or substantial and costly modification of the furnace design and reconstruction of the surrounding auxiliaries.

That means, that so far known, more primary energy efficient metallurgical furnace design could not simply and directly replace the Electric Arc Furnace.

Further continuation of firing of the burner is extremely inefficient and wasteful (after being fired over 20% of the melting time the efficiency of the stationary burners usually drop from about 75-80% in the begin of the melting process, to about 20-30%).

This is the actual situation, although there have been during last 20 years, "simple" but more or less successful burners using coal combusted by air; recently performed practical tests have shown insufficient temperature of coal-air flame.

An other problem which has not yet been solved to the satisfaction of the steelmakers, is the--as much as mechanized as possible--introduction-injection system and apparatus for carbonaceous (coal, coke, anthracite) and slag forming (CaO) materials into the steelmaking Electric Arc Furnace.

It appears, that the main reason why none of the several available systems has not emerged as a leader is the fact that none of them has functioned properly at all of time.

It is however, very well known that open slag door means higher electric energy consumption and increased production of NO.sub.x.

Another, functionally inadequate characteristics, common to almost all of the state of the art lance systems, is that most of them have coal and oxygen introduced through two independent pipes.

This arrangement is not capable of mixing properly pulverized coal and oxygen before entering the slag-steel interface.

In other words, the Table II., is attesting beyond any reasonable doubt, that any Electric Arc Furnace using electricity generated at a Power Plant burning coal or natural gas is extremely inefficient with respect to primary energy contained in natural gas or coal.

However, cost of producing the electricity from coal is increased by several additional charges depending on location and resulting in its higher a commercial price.

Unfortunately, the lower price of electricity generated by using the coal instead of natural gas, is many times overcome by the fact that combustion of the coal with air, produces about 2.2 times more CO.sub.2 and CO in addition to 1.4 times more of NO.sub.x and about 38 scf / ton of SO.sub.2 (natural gas does not produce SO.sub.2).

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