DE281096C - - Google Patents

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JVe 281096 CLASS \ 2 / £. GROUP

. CARL WALDECK in DORTMUND. Process for obtaining ammonia from coke sludge.

Patented in the German Empire on August 15, 1913.

The enormous masses of coke sludge falling on the coking plants (coke from ο to 15 mm grain) are so far worthless, since the coke quenching due to its fine grain and its heavy Ignitable as a fuel not suitable; it is run on heaps or at most as Road construction material used.

The nitrogen content of the coke sludge is now about i, o to 1.4 percent of the ashless Coke substance, depending on the type and origin of the coke sludge; at the high price of nitrogen products, especially of ammonia, it is clear that the extraction of the nitrogen content in the form of ammonia would represent a high level of economic success.

Attempts have already been made to obtain ammonia from mountains of laundry (coke sludge etc.), but without arriving at useful results, namely from the following Reasons:

The release of nitrogen from the coke oven in the form of ammonia is only possible through Processes are possible in which the carbon content is simultaneously dissolved, i.e. H. burned

or the like, and this is the difficult point that has made all previous attempts fail; because the ammonia decomposes into its elements at about 500 to 550 °, while Oxidation of carbon by means of oxygen in air has a high temperature requires. The ignition temperature of the coke is 700 ° (see Lanyi, calculation the steam boiler, etc., Verlag Baedeker, Essen, page 10), the combustion temperature of the coke is still considerably higher, d. H. at a temperature at which the resulting Ammonia instantly breaks down into its elements. Accordingly, the attempts have the Gasifying coke in generators with air with a supply of steam does not lead to any result led, d. H. only to generator gas without ammonia.

Experiments led to the realization that the coke sludge to be processed on ammonia to absolutely uniform, namely the appropriate temperature between formation and decay of Ammonia must be brought when the conversion of the nitrogen content into ammonia should run approximately theoretically.

For this heating, according to the present invention, the electrical path, namely the Internal heating, used.

It was impossible to foresee from the outset whether coke extinguishers for electrical interior heating would at all was usable and whether the appropriate temperature conditions were used when using them to be achieved. ·

In order to determine the electrical resistance of the coke, a firebrick tube was used 44 mm wide and 315 mm long with granulated coke with a grain size of 0 to 15 mm filled, loaded with a total of 228 g and the mass with the help of two end electrodes made of graphite electrically heated. The following measured values were obtained:

150 °. · .. 90 volts 4 amps 22.5 ohms, 200 ° .. • · 83 - 5 16.6 - 300 °. . .. 86 - 5 17.2 - 400 ° .. .. 86 - 6th 15 - 70 430 °. · .. 76 - 7th II 440 °. . .. 69 - 9 7.66 -.

Claims (1)

It follows from these figures that the resistance of the coke and thus the required terminal voltage falls quite considerably with the temperature, which is not only due to the negative temperature coefficient of the coke, but probably also to the structural change of the whole mass, since very slight changes in pressure result in significant deviations from the values displayed by the instruments. Direct and alternating current are equally suitable; three-phase current can possibly be used if the furnace shape is selected accordingly. Temperature measurements showed that with this electrical heating the coke sack filled in the tube is easily brought to a technically uniform temperature. When water vapor is passed through the tube filled with coke extinguisher and brought to the appropriate temperature, the water vapor decomposes, which leads to the complete release of the nitrogen contained in the coke extinguisher in the form of ammonia. On average, 88 to 99 percent of the nitrogen contained in the coke sack was released as ammonia. The yield was highest with not too fine coke powder with a moderate ash content, but was most unfavorable with high ash content (40 to 50 percent ash) coke sludge with fine grain. The temperature of the coke quench loaded into the tube can be selected to be higher than the decomposition temperature of the ammonia, whereby the reaction proceeds faster, while the ammonia formed is enveloped by the water vapors and thus removed from the decomposition, the water vapor also having a lower temperature than the temperature of the electrically heated coke oven can pass the tube. In the process, not only is the nitrogen content of the coke sludge in the form of ammonia won, but at the same time there are significant amounts of hydrogen, which the Further increase the profitability of the process. Namely, the process proceeds according to the experiments according to the formula C + 2H ₂ O = 2H ₂ + CO ₂ . So there are about 44 cbrn of hydrogen per 12 kg of carbon, the latter fairly large can be obtained purely as a result of the ease with which the carbon dioxide can be switched off and an excellent one Product for water gas welding, etc. The experimentally observed formation of considerable quantities was interesting Methane, which probably goes by the formula: = CH ₄ + CO ₂ . It is not impossible that the favorable yield of ammonia is due to the above Observation can be attributed to the fact that a structural change as a result of the electrical internal heating the whole crowd enters. For reasons of profitability, the exhaust gases from coke gas may be used as water vapor Use operated gas machines, which mainly consist of water vapor and 500 ° Have temperature. Pa ten τ-An SPRU cn: Process for the production of ammonia from coke sludge (fine-grained coke) by means of Water vapor or a mixture of water vapor with other gases for the conversion of the starting material nitrogen contained in ammonia at a favorable temperature, characterized in that that the temperature is electrically heated by internal heating (resistance heating) of the starting material is generated.