DE1063623B - Process for the production of a non-carbonic acid combustion gas - Google Patents

Description

The invention relates to a process for the production of carbon dioxide, dry combustion nungsgaecn, as they are to a large extent ice protective gas « in various industries before aJlcm in Furnaces for metal treatment are used.

Such combustion gases are known in Obtained by controlled combustion of hydrocarbons with air. Mast are called Fuels Gases such as natural gas (natural gas), coke oven gases. Butane and propane. By regulation i * The ratio of air to gaseous fuel can be used to produce combustion gases which Contain varying proportions of hydrogen, carbon dioxide, carbon dioxide and nitrogen. A gas analytical one Table for combustion gas, as it is at the combustion of natural and coke oven gases is disclosed in U.S. Patent 2085586 contain. From this table it can be seen that with increasing ratio of air HU is gaseous Hydrogen and carbon dioxide fuel is reduced and the carbon dioxide content is increased, until with 100% air supply the hydrogen and Carbon dioxide levels have dropped to 0.

A carbon dioxide, dry combustion gas, which is used as a protective gas in furnaces, annealing, normalizing, hardening, brazing, sintering and the like can be manufactured in one device, as de in the General Electric Review of March 1949, P. 29 and 30. as well as from May 1949 on p. 35 and In U.S. Patent 2,631,135. 3 “According to these publications, they give the combustion chamber leaving gases through a cooler in which the water vapor is partially separated will. The cooled gas and condensate are separated from each other, and the gas is in an absorption tower completely freed from COj. An aqueous monoethanolamine solution is used for COj'Abiorption used in the tower over large surface area Filling material trickles down Then the gas goes through a cooler, and the 4 " Liquid is returned to the absorption tower. Finally, in various coolers and dryers, the dew point of the gas is reduced to -40 ° C lowered. The dry gas goes straight to its place Use. $ 4

In operation of such a device it has now been found that the gas leaving the absorption tower contains excess moisture in the form of a dense mist which cannot be removed by passing the gas through a gas meter and a γ> liquid separator. Rather, the mist passes through the cooler, which is used to partially dry the gas, and enters the chemical dryer, where the remainder of the process is used to produce a non-carbonated combustion gas

Applicant:

General Electric Company, Sdienectady, N.Y. (V. SL A-)

Representative: Dlpl.-Chem. Dr. phll. H. Stebenelcser, Patent attorney, Cologne 1, DeWtimaanbaus

Bcaaipxudilc priority! V. St r. America from Wed 8th 1953

AlIeD Gerald Hotchkiae, Schenectady, N.Y. (V. St. A-). is named as inventor woiden

activity should be removed, but because of the raised Fcuchtigkcitffdialtes of the gas is heavily overloaded The mist consists of extremely fine particles that cannot be filtered through any kind of filter or have a cooling procedure removed.

It has now been found that conditions for fog formation are given when certain Natural gases are burned in the combustion chamber of the gas generator and these gases in the Absorptianstnrm are directed and the mist Exat form in the absorber tower, although the entering gas is fog-free. The formation usually takes place when high ratios of air eu gas in the combustion chamber be respected. Will coke oven gases when burned, the phenomena described occur more intensely, and fog formation occurs Use of high ratios of air »1 gas particularly large.

Often, the combustion is carried out with more than 100 ⁹ / · of the theoretical air requirement, for example when a gas is to be produced for Sp &ltweckc; In these cases, too, it is advisable to remove the carbon dioxide from it in order to prevent the workers from being harassed. In one case, the application of more than 100 * 1 * air and natural gas resulted in conditions under which the mist of monoithanotaniine and water carried excess amounts of absorption and the monoethanolamine change in the mist

Claims (3)

Machines, such as those used in compressors, dissolved lubricants. If carbonic acid-free combustion gas containing this mist is passed through a heater in which the gas and mist are heated to 65 to 95 ° C, the mist is converted into steam and the steam can be condensed out in a cooler. However, the heating and cooling are expensive and are therefore expediently avoided. According to the invention, the formation of a mist in the absorption tower, in which the acidic constituents, in particular CO2, are washed out with an aqueous monoethanolamine solution, is avoided by passing the carbonated combustion gas through a hydrated iron oxide-containing cleaner before the CO2 is absorbed. In addition to hydrated iron oxide, the cleaner appropriately contains an alkaline agent, such as lime, and a material that loosens the cleaning compound, such as wood shavings. In a special case, a colloidal, alkalized ferrous oxide hydrate on wood chips, corn cobs or blown blast furnace slag is used as cleaning material, in a mixture of about 9 to 11 kg of the cleaning mass on 351 of the loosening material. The alkalized ferric oxide hydrate is produced from material containing iron, such as is obtained from bauxite digestion with alkalis. This mass is very finely divided, contains iron oxide hydrate, is free of organic substances and iron and contains a high percentage of active alkali. This mass can be regenerated by blowing air through it without removing it from the tower. The desulphurisation tower is not used to remove hydrogen sulphide from the burned gas, because some burned gases do not contain any hydrogen sulphide at all, but still cause a mist, while other burned gases sometimes contain hydrogen sulphide without forming a mist. Even sulfur dioxide in the burnt gas does not simply cause fog to form; but when sulfur dioxide is added to natural gas which has been burned with a high ratio of air to gas, mist is formed, and mist formation increases to a fair degree if a gas has been burned which contains sulfur dioxide and at the same time an excess of air. With excess air, i. H. of more than 100% of the air requirement, fog also forms when hydrogen sulfide is added to natural gas. So neither hydrogen sulfide nor sulfur dioxide cause a mist formation by themselves if they are introduced into the gas emerging from the combustion chamber of the gas generator before it enters the tower to remove the carbon dioxide. However, when a high ratio of air to gas is used in the hot combustion chamber of the gas generator, sulfur dioxide forms a sulfur compound in the gas to be burned, the presence of which in the burned gas causes a mist in the tower to remove the carbon dioxide. However, if the gas according to the invention is passed through a conventional tower containing iron oxide, as is otherwise used to remove hydrogen sulfide from natural and coal gases, no mist will form in the burnt gas in the absorption tower. Patent claims: 1. A method for producing a non-carbonic combustion gas by burning Hydrocarbons with air and absorption of the carbonic acid formed with aqueous monoethanolamine solution, characterized in that the carbonated combustion gas is hydrated prior to the absorption of the carbonic acid by a Cleaner containing iron oxide is passed. 2. The method according to claim 1, characterized in that the iron oxide hydrate by addition is made alkaline by lime. 3. The method according to claim 1 or 2, characterized in that the iron oxide hydrate in colloidal Distribution on a porous mass or loose particles such as wood shavings is used. Considered publications:
German Patent No. 476 513;
British Patent Nos. 448 008, 371 054;
Ivor Jenkins: "Controlled atmospheres", 2nd edition, 1951, pp. 150 to 155. ® 909 608/279 8.59