Abstract: An apparatus for melting a metal provided with a metal melting furnace (10) for melting a metallic raw material with a flame of an oxygen fuel burner (11) to which oxygen is supplied as a combustion assisting gas; and an oxygen supply source for supplying oxygen as a combustion assisting gas to the oxygen fuel burner (11). The metal melting furnace (10) has a preheating section (13) for preheating the metallic raw material above a melting section (12) to which the oxygen fuel burner (11) is attached and a reduced section (14) located between the melting section (12) and the preheating section (13), the reduced section having an inside diameter smaller than those of the melting section and preheating section. The oxygen supply source is a pressure swing adsorption separator (30) employing an adsorbent which adsorbs preferentially atmospheric nitrogen and supplying a low-purity oxygen having an oxygen content of 65 to 94% to the oxygen fuel burner (11).

Abstract: A combustion type detoxifying apparatus which carries out detoxifying treatment of a raw gas containing toxic components injected through a burner (3) into a combustion chamber (1) by allowing the toxic components to burn or undergo pyrolysis. The burner (3) has a raw gas nozzle (32a) for injecting the raw gas, a lift gas nozzle (32b) for injecting an inert gas, a raw gas combustion assisting gas nozzle (32c) for injecting a gas for assisting combustion of combustible components in the raw gas, a fuel gas combustion assisting gas nozzle (32d) for injecting a gas for assisting combustion of the fuel gas and a fuel gas nozzle (32e) for injecting the fuel gas.

Abstract: Disclosed is a melting furnace of metals and melting method thereof, which can control the rate at which a metallic raw material is introduced from a preheating section to a melting section within an optimum range and which can achieve efficient melting of the metallic raw material using oxygen burners only. The metal melting furnace has a melting section (22) provided with oxygen burners (21) and a preheating section (23) for preheating the metallic raw material located above the melting section, with a reduced section (24), having an inner diameter smaller than those of the melting section (22) and of the preheating section (23), being located between the melting section (22) and the preheating section (23).

Abstract: Disclosed is a method of melting a metal. In a melting furnace, a metallic material is melted by heating it directly with the flame from a fuel burner using an oxygen gas having a purity of 60 to 100% as a combustion assisting gas. Meanwhile, the combustion assisting gas is heated before it is fed to the burner.

Abstract: Disclosed is a method of melting a metal, which can demonstrate improved heat efficiency, increased yield and minimized pollutive gas generation. In this method, a metallic material stacked in a melting furnace is melted by heating it directly with the flame from a fuel burner using an oxygen gas having a purity of 60 to 100% as a combustion assisting gas. The oxygen gas is burned at an oxygen-to-fuel ratio of 0.55 to 0.99, while the unburned portion of the combustion gas is allowed to burn by O.sub.2 supplied separately through oxygen lances. Meanwhile, the metallic material is preheated by burning the unburned portion of the combustion gas, whereas the combustion assisting gas is heated before it is fed to the burner.

Abstract: There is disclosed an oxygen heater, which uses a portion of supplied oxygen as auxiliary combustion oxygen, a hot oxygen lance and a pulverized solid fuel burner, both having oxygen heaters. The oxygen heater has a combustion chamber for burning fuel with a portion of the supplied oxygen. An oxygen-jetting opening is disposed around the combustion chamber. The oxygen jetted out of the opening forms a gas curtain between an internal wall of a mixing chamber and a flame produced in the combustion chamber, and is heated by the flame. Both the oxygen lance and the burner includes the above-mentioned oxygen heater.

Abstract: There is disclosed an oxygen heater, which uses a part of supplied oxygen as auxiliary combustion oxygen, a hot oxygen lance and a pulverized solid fuel burner, both having oxygen heaters. The oxygen heater (1) has a combustion chamber (4) for both mixing and burning fuel with the part of the supplied oxygen. An oxygen-jetting opening (8) is disposed around the combustion chamber. The oxygen jetted out of the opening forms a gas curtain between an internal wall (2) and a flame (10) produced in the combustion chamber, and is heated by the flame. Both the oxygen lance and the burner includes the above-mentioned oxygen heater.

Abstract: There is disclosed a monofuel combustion process for burning pulverized coal. According to this combustion process, pulverized coal having a temperature (t) produces a stable flame having a temperature of not less than 2,000.degree. C. when it is burned with an auxiliary combustion gas having an oxygen content (C). An auxiliary combustion gas is preheated, and then pulverized coal is burned with the preheated auxiliary combustion gas, or, after both an auxiliary combustion gas and pulverized coal are preheated, the gas and the coal are mixed and then burned. In the gas preheating step, the temperature of the auxiliary combustion gas is raised to the temperature T defined by the following formula: T.gtoreq.exp{14.14-1.84 ln C-exp(0.01127t-3.444)}.

Abstract: A burner for flame-spray coating, being capable of sufficiently high flame temperature and being capable to flame-spray powder material of high melting point by using such fuel gas as C.sub.3 H.sub.8 or C.sub.4 H.sub.10 with high efficiency of deposition, having a gas-powder stream supplying conduit connectedly arranged at the rear portion of a pre-mix combustion chamber, from where gas-powder stream being jetted into the chamber, characterized that at least a series of auxiliary combustion gas (oxygen, oxygen enriched air) supplying passages are annularly provided on the conical wall face of said chamber with the direction of converging toward an opening for flame jet and the axis of the pre-mix combustion chamber.

Abstract: A method for supplying raw powder material such as metal, intermetallic compound or ceramics to a spray coating burner wherein fuel gas or auxiliary combustion gas or their mixed gas is used as jet gas, any one of these gases is introduced under control of the flow rate thereof into a suction chamber of an ejector to serve as suction gas whereby the supply amount of said raw powder material to be fed to said spray coating burner can be controlled.