Procedure for the production of hydraulic bonding agents

The invention concerns a procedure for the production of hydraulic bonding agents, like cement u.dgl., from brikettiertem raw meal, in which the calcium component consists hauptstlchlich of burned lime, using the Klinkerbildungsw rme. The production of cement from brikettiertem quicklime raw meal is actually well-known. The warmth necessary for such processes is produced by fuels. Thus raised the price of siqh the procedure and can become even unprofitable. Furthermore it is well-known that the Klinkermineralbildtmg from the oxides of the calcium, silicon, A luminiums and the iron exothermically, i.e. under release of warmth verI/iuft, and that it is terminated when using quicklime as raw material with approximately 900 to 950oc assigned and after conclusion of the Stntemng at temperatures around 1350 to 1400oc. Depending upon the composition of the clinker, i.e. depending upon the content of the individual oxides the freed warmth amounts to 90 to 110 KcaI/kg Kltäker. On the average a value of approximately 100 Kcal/kg clinkers can be taken. It was now surprisingly found that one can manufacture with very smaller and even without fuel supply hydraulic bonding agents, like cement u.dgI, if one in accordance with the invention lfi the raw meal with a Rtickstand of less as 10%, preferably less than 8%, on that 4900 mesh filter IN 4188) with a light mesh size of 0, 09 mm if necessary under additive of small bonding agent quantities brikettiert, on which the briquettes are given up to a reactor in its reaction zone her the against the current by hot air, which was warmed up before by the glowing clinker, on the reaction temperature of the KlinkermineraIbildung is brought, whereby the amount of air 0 68 to 0, 89. , preferably 0 72 to 0, 78 Nma/kg taken off clinkers amount to. It is zweckmtlBig that one the Ansgangsstoffe for the raw meal briquettes, in particular the clay/tone, the sand and/or the blastfurnace slag before mixing with the quicklime trockneh because otherwise the quicklime with the dampness would slam oneself shut to calcium hydroxide converts and from there EN the briquettes no more than quicklime is not present. Preferably is the content of the raw meal and/or the Rohmehlbri95 chains at clay/tone, hydrated lime or Kalziurnkarbonat to be only so high that to decomposition of these materials at the most about 70 Kcal/kg clinkers are used. Appropriately solt from there the sum of the quantities of clay/tone, Kalldaydrat and KaIziumkarbonat to be limited, in order not to endanger the Wärmebflanz. The clay/tone does not only contain “mechanical” dampness but also chemically bound water. This water is driven out at higher temperatures and requires a certain amount of heat exactly the same as the Dehydratisierung of possible hydrated lime portions or the Austreibnng of carbon dioxide from possible Kalziumkarbonatanteflen in the raw meal. There it itself around chemically bound and in the warmth split offable Wasserbzw. , Is designated this feature acts COz portions summarily as decomposition. It can be of advantage further to drain the clay/tone before. The formation of the clinker minerals sets when using quicklime as lime component, if the conditions of the procedure according to invention are kept, after a heating up of the raw meal briquettes to 900 to 960°C noticeably and is after conclusion of sintering at approximately 1350 to 1400oc terminated. Between these two temperature ranges becomes free the mentioned amount of heat from 90 to 100 Kcal/kg of clinkers, which stand for the heating of the property for order. SeIbsWerständlich it must be ensured that the perceptible warmth of the developed Klihkers, which amounts to with 1400oc about 865 Kcal/kg clinkers remains possible completely in the system. In addition it is first important that the reactor, which can be trained according to kind of a shaft kiln, is well insulating and radiation losses of at the most 0Kcal/kg clinker permits. This is easily attainable with well-known technical means. The perceptible warmth developed handles by entgegenstzömender air is taken up, which delivers the warmth to the Rohmeblbfiketts and it to mindestem to reaction temperature warms up. This 0, 68 to 0.82 Nm/kg clinkers, wr ugsweise 0, are according to invention 72 to 0, 78 NmS/kg. If one goes from briquettes with a raw meal composition to, which sets an amount of heat free of 90 Kcal/kg with the Klinkerbfldung, then an amount of air will be sufficient, which lies to lower Grenzedes of indicated range. On the other hand one becomes an amount of air, which is because of the upper border of the range, uses mUsseu, if due to the composition of the raw meal the freed W rmemenge close 110 Kcal/kg clinker lies. For the perfect operational sequence of the procedure according to invention it is appropriate, if the temperature of the exhaust air, i.e. after passing with RohmehlbrlkettsbeschfcktenVorwärmezone, does not exceed 200°C. This corresponds to a calorific loss of approximately 46 Kcal/kg clinkers with 0, 8 Nms with a Bezugstemperamr of 20oc. High exhaust air temperatures would cause a too large calorific loss of the system. One does not let fall the temperature of the exhaust air appropriate however under the dew point, because otherwise the water in the top of the Vorwärmzone, escaping from hydrated lime or clay/tone, condenses and forms with the quicklime calcium hydroxide, to whose decomposition further amounts of heat to be spent would have. It is favourable according to invention, if the perceptible warmth of developed clinker is transferred to a large extent to against-flowing air. Therefore is to be made certain that the clinker withdrawing from the reactor exhibits a temperature of at the most 150°C, what about 25 Keal/kg clinkers with a Bezugstemperatur of 20oc corresponds. A Wärmeverlnst in this height is easily portable. Preferably however the temperature of the withdrawing clinker should be lower than 130oc. One can adjust these temperature conditions in simple way by calculation of the against-flowing amount of air, which is called at high clinker discharge temperature one the amount of air accordingly will increase and with too strong dropping of the clinker discharge temperature will decrease. It is to be pointed out that the possible losses for radiation warmth of maximally 40 Kcal/kg clinkers as well as the calorific loss of approximately 25 Kcal/kg clinkers and the heat capacity of the delivered clinker of approximately 25 Kcalikg clinkers can be taken only then in purchase, if other amounts of heat, approximately for endotherms chemical reactions, as Dehydratisierung of CaIeiumhydroxydanteflen, drainage of clay/tone or Entsäuemng of remaining Carbenate not to be spent to have. With the above data it acts from there urh the most unfavorable conditions. In practice one will have to take such possibilities into account for calorific loss, so that one not under these most unfavorable conditions regarding the Abstrahlungsvefluste, which can work Ablnfttemperatur and the heat capacity of the clinker, if the procedure according to invention is to function satisfyingly. Of course it is also possible to regulate the clinker discharge temperature with continuous amount of air over the clinker discharge quantity i.e. at high clinker discharge temperature one will decrease and at low temperature will increase the lack of discharge. A schematic surveys the procedure gives the design. The execution of the procedure according to invention becomes relatively simple. As mentioned, one can as reactor --1-- a kind shaft kiln with fireproof fodder and isolation use, as ste also for neutralizing lime uud dolomite are used. Such shaft kilns must be naturally carefully insulating. The raw meal briquettes become in usual way above --2m given up. For starting the reactor in the reaction zone the N3N must, in --4-- a temperature of for instance 1400°C and with m N such of for instance 900°C prevails, to briquettes present first on the Kltnkerrnineralbtldungstemperatur to be brought. The cooling of the developing clinker from downside ago air becomes, best with a blower the against the current --6--, imported. This air takes up the perceptible warmth of the clinker and gives it after passing the sinter zone --3-- to the raw meal briquettes in the Vorwgrmzone --7-- off, whereby these are warmed up to the clinker education temperature. The procedure requires from there only for the start-up of the furnace fuel. Adherence to the optimal conditions is not necessary a further task of fuel. A lively end of the shaft kiln lies the clinker cooling zone --8; the clinker becomes with maximally 1500Cbei m9-- delivered. The exhaust air with maximally 200Oc verlgBt the furnace --! 0--. The following exemplary data are to point the heat balance out of the procedure. During good lagging of the pit reactor, according to e.g. a wall calorific loss of about 10 Kcal/kg clinker, serving for the execution of the procedure after the invention, a temperature of the withdrawing clinker of about 70°C = 10 Kcal/kg clinkers and an exhaust air temperature of 100oc = 20 Kcal/kg clinkers could e.g. 100 - about 40 = about 60 Kcal on the decomposition of clay/tone, hydrated lime and remainder carbonate be spent. So one a R can e.g. use hmehl, which as Hydraulefaktor clay/tone contains, and which 3, 5% calcium hydroxide as well as 9% calcium carbonate contains. The energy quantities which can be spent on the decomposition of these materials 2 amounts to! , 7 and 32 Kcal/kg clinkers. According to invention indicated the refinement of the raw meal and/or the individual components is necessary, so that a tlberhöhter free lime content in the clinker is avoided. Of course is to be provided for a good mixing of the components. It can be wärmewirrschaftlich ven advantage, if air inserted into the pit reactor is driven totally or partly in the circle, as strichliert in the design suggested. Hiedurch decrease at the same time the costs of the dedusting of the exhaust air. The production of the briquettes can, into actually well-known-wise, on which in the einschl$lgigen industry used machines take place, whereby as bonding agents water or other materials use usual for it can find. After the invention one knows not only the descriptive procedure for production of hydraulic Bindeminel would drive through, but also all other procedures, which can be accomplished under freed warmth exothermically in a pit reactor.