DE756844C - Process for the production of acetylene and ammonia soda - Google Patents

Description

Process for the production of acetylene and ammonia soda At the in continuously increasing production of acetylene from calcium carbide there are very large amounts of hydrated lime as a waste product, which is often disposed of Causes difficulties and expenses. In Vogel's work, "The Acetylene," some uses are given for this waste lime, but its intense smell is already pointed out, which is very annoying in many cases is, especially since certain components of the Karbi, dkal # ks also in a healthy sense make themselves adversely noticeable. Another waste product from calcium carbide manufacture are the carbon dioxide-containing exhaust gases from carbide furnaces. Since recently many closed Carbide furnaces can be used, according to information from T a u s s i g, »Die Industrie of calcium carbide, which extract carbon dioxide in a concentration of more than 60%; nevertheless, in practice, these swaths have mostly been burned uselessly or, in the best of cases, have been used as heating material.

It has now been found that these two waste materials, the carbide and Acetylene production in the state in which it occurs, valuable Service; in the production of ammonium soda l: istal can, with the otherwise for The corresponding limestone and colile quantities required are saved if one considers the production of acetyls via carbide and the production of ammonium soda united with each other.

The soda process is known to be based on the following reactions, whereby the intermediate stage of sodium bicarbonate formation is omitted as it is only is about showing the converted equivalent amount: "21aC1 '-. 2 \ H @ + CO @ -f-H20 = Na2C03 + a NH4Cl 2 N? H4 Cl + Ca (O H) 2 = 2 N H3 + CaC12 + H20 when performing In the soda process, the necessary amounts of lime and carbonic acid are obtained by burning fully extracted limestone. In the same way, that required for carbide production is also used Calcium oxide made by burning limestone. Those in carbide and acetylene production The set quantities of raw materials are as follows: Ca0 + 3 C = CaC2 + C0 + 1/202 = C02 CaC .., + 2 H20 = Ca (OH) 2 + C2H2 It can be seen that at theoretical conversion the soda required for i 1101 Amount of calcium oxide and carbonic acid in the manufacture and decomposition of i 12o1 calcium carbide can be won.

Even if it is the amount of raw materials used in practical implementation deviate more or less from the specified equivalents, however Soda, calcium carbide and acetylene are produced in such large quantities that from the standpoint the quantitative; n size o; rdnu.ng companions, relationships often find each other let where the production of soda, carbide and acetylene fit together in such a way that the falling carbonic acid and the carbide lime with great advantage for the production of Amtiloniaksoda can be used.

About the amounts of calcium oxide and carbonic acid that can be obtained in practical operation in the production of carbide and acetylene, see U 11 man, Enzyklopadie der technischen Chemie, Vol. II, p.778, the following information: A. Acetylene production Carbide production 10000 kg carbide with 81o kg CaC2, 130 kg dissolved Ca0: 355 kg CO from lime -481, t-, CO from electrodes together 403 kg CO When acetylene is produced, 710 kg of CaO are obtained from 810 kg of CaC2, plus 130 kg of CaO in dissolved CaO. Total accumulation per 1000 kg of carbide 8d.0 kg of CaO.

The .I03 kg CO give kolivertiert or burned in theory 630 kg CO "practically deeply 970 / 0i-er yield cl - r conversion around 61 o C 0- kg B. Ammoniaksodaerzeugung The consumption of lime (CaO iooo / o) for Expulsion of the ammoiiial; s (distillation) Ire '620 is from the bicarbonate filter liquors up to 66o kg Ca 0 per 100o kg soda. The carbon dioxide consumption 1: egt at .15o up to 50o kg CO., for 100o kg of soda. The purple lilacs from the Karbi ovens acid full 61o kg CO., per ton of calcium carbide is therefore sufficient for the production of i2io to 135o kg of soda, for which 62o to 66o kg per ton, ie 75o to Sgokg CaO which in this quantity from the Caleium- karli: i decomposition with 84o kg available stand. The result is the following balance: '@cetyleilergenerations 840 kg of Ca 0.61 o kg of CO.,.

Ammonia soda production For i2io up to 1350 kg ammonia soda 75o to 8g0 kg Ca O.61 o kg CO are consumed.

So one can see that also under the conditions of practical operation The quantities of lime supplied by the acetylene production are carbonated with the vom: #, minoniakso, the required quantities match.

So, # vob; l in the production of Ca, l.ciumkarbids as well as soda The plant and operating costs of the lime kilns play an important role. With the important one Extent to which both factories are operated. it is also generally economical It is important that when the two factories are merged, both the plant and operating cost for lime burning than the raw material quantities of limestone and coal used only once %% - must earth, with the acetylene ore: ° -tigting Calcium hydrate, previously regarded as an annoying waste product, is eliminated and a beneficial one Use is fed.

The technical -, progress of the method of the invention is based on the knowledge that carbonic acid in sufficient concentration from the exhaust gases of the carbide furnaces and in the case of carbide conversion with water, hydrated lime in the appropriate proportion and both raw materials can be obtained as cheap waste products can that on this basis a large-scale production of Alnmonia: l: soda is possible. Included. is still important; that the carbide lime in the Acetylene production occurs as hydrated lime, i.e. in that for ammonia soda production necessary condition, which means that the plant and operating costs of the large lime slaughterhouse are generapart can be.

There are already some information in the above-mentioned work by Vogel about the possibility of recycling the Kärbi! d lime. But this will nothing was said about its useful use in ammonia and sadaafabrication; because in the soda process this lime can only be used when at the same time the corresponding amount of high-percentage carbon dioxide by other means than by burning lime is delivered.

The use of the carbide furnace gases for the production of soda offers the possibility of from the closed Karbi, carbonic acid may be allowed in a higher concentration than through To gain burning in the lime kiln, which facilitates the precipitation of the sodium bicarbonate and the necessary equipment will be simplified and made cheaper. The extraction of high percentage Carbonic acid from carbide furnace gases can either be produced by burning the carbon dioxide with oxygen or oxygen-free: cher air, which is often found in Karbi-.dfabriken, -which produce calcium cyanamide in addition to acetylene, is obtained, or through Conversion of the carbon oxide take place with water vapor. In the latter case you can either separate the carbonic acid from the hydrogen by means of pressurized water washing and in almost pure form in, introduce the soda process. But you can also use the carbonic acid-hydrogen mixture Use immediately for the precipitation of sodium bicarbonate according to the Solvay process. The carbonated hydrogen gas can be used to synthesize Ammonda'k.

In British patent specification 1 58 863 it has already been described, by converting the carbon dioxide contained in the water gas, to obtain carbonic acid and hydrogen, to use the carbonic acid according to the Solvay process for the precipitation of sodium bicarbonate and also to use the ammonia produced from the hydrogen in the soda process to introduce. In the description of this process it is also stated that in this way one could save the expensive equipment and operation of the lime kiln for the soda process.

Operation of the ammonia soda process with continuous feed of ammonia and extraction of corresponding amounts of chlorammonium is just taking the often unsatisfactory condition of depositing large amounts of chlorammonium is possible. In contrast, the source of chloric acid proposed in British Patent 158,863 is unusable for the riormalen ammonia soda process because for the recovery of the Ammoti-i, aks no lime is available from the mother liquor. In addition, the method of the British patent overlooked that with successive introduction of synthetic ammonia, in the soda process only about half of the amount due to conversion Carbon dioxide obtained from carbon dioxide from generator gas and water gas can be used can, while the other half is lost.

In contrast, the balance presented above shows that the resulting carbonic acid and hydrated lime amounts of acetylenewiiiiiuiig well, the consumption of the connected Fit soda factory. However, the method according to the invention does not meet this precondition limited, but it applies, even if for some reason only subsets der Aoetylien: by-products are used in the extraction of soda or if For soda production: g additional carbonic acid or lime procured from another source or if partially chlorammorni @ u, ni on the soda process as a life product is removed.

The invention also relates to the case. That the calcium carbide is not obtained in electric ovens, but in purely thermally operated ovens and carbon dioxide or carbonic acid from the reaction of carbide formation is used, likewise in the event that carbide and acetylene production are combined in one operation united «-erden and thereby Calciu.moxyd ,carbonoxyd- l> betw. Colilenic acid accumulate.

A particular advantage of using: the proposed method The waste material produced lies in the fact that it can be transported more easily over a long distance Stretch. Regarding the koh: lenoxyd@lia.l.tisen exhaust gases, which are also in dier Carbide factory can be oxidized, that goes without saying. However, can also the hydrated lime over long distances. blown away or carried away as Kalkinilch, after which they in, d-er Sodafabri'k by settling or filtration to the desired Water content is brought. In the soda factory, the hydrated lime is turned into chlorocarboniccium converted, which can easily be removed by discharging into larger watercourses or recently a valuable auxiliary material in the construction industry to an increasing extent and has become in road construction or road maintenance.

Claims (2)

PATENT CLAIM: Association for the production of acetylene via Calci, umkarbi.d with the production of soda by the ammonia process by the waste evacuated during carbide extraction after oxidation of the carbon contained in it o @ xv, ds as a source of carbonic acid for the precipitation of bicarbonate and for the production of aoetylene accumulating quick lime for the decomposition of the salmiac mother liquor is used or at insufficient amounts of lime resulting from processing the relevant Part of the ammonia required for the soda process by synthesis from the hydrogen produced by the carbon dioxide oxidation is supplemented. For demarcation of the subject matter of the invention from the prior art are the following in the granting procedure References have been considered: British Patent No. 158,863; Tau s i g, "Die Industrie des Calciumkarbids", 193o, p.25r; Vogel, "The Acetylene", 2nd ed., 1923, p. 365 ff.