DE30327C - Apparatus for the preparation of strontium oxide from strontium carbonate by means of superheated steam - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

CLASS 7B: soda, potash and alkalis.

HIPPOLYTE LEPLAY in PARIS.

Water vapor.

Fatentirt in the German Empire on May 27, 1884.

In the description of the patent no. 28757 and No. 29153 protected proceedings inventor has a complete agreement in the behavior of the barium and Strontium carbonate compared to the effect of the superheated steam for the purpose of illustration the hydroxides assumed.

Experience has shown, however, that this agreement is not yet complete, so that "one must take account of the relevant differences; furthermore, for the Success in the preparation of strontium hydroxide and its use for sugar extraction peculiar conditions exist, which differ from the conditions for the same success with barium hydroxide are essentially different and a complete change for strontium hydroxide make necessary in the processes and apparatus previously described.

These methods and apparatus for the preparation of strontium hydroxide form the Subject of the present patent.

The inventor has observed that the strontium hydroxide is close to its melting point at one point lying temperature loses its equivalent of water, even under the influence of sufficient superheated steam, while the barium hydroxide does not change at the same or even higher temperature.

As the strontium hydroxide loses its water, it solidifies, and this solidification there would be a great deficiency in the conversion of strontium carbonate into hydroxide by the above-mentioned procedure.

In fact, when the superheated steam is at a temperature in which the dehydration of the hydroxide formed occurs, instead of liquid Hydroxide which could flow out of the lower part of the apparatus, solid strontium oxide, which remains in the place occupied by the carbonate.

The slight difference between the temperature at which the strontium carbonate decomposes for the formation of strontium hydroxide and the dehydration of the latter, could in certain cases in the series of Operations give rise to difficulties in that there is soon a fluid and soon would form a solid mass.

In order to avoid these difficulties and to make the operation easy, constant and Strontium carbonate can be used regularly in one and the same operation by superheated steam successively and almost at the same time in hydroxide and in convert anhydrous oxide.

The apparatus used by the inventor for this conversion of strontium carbonate, is based on the use of superheated steam, which removes the carbonate from the glowing heat at which it enters the Decomposition apparatus was introduced to the temperature required for its decomposition heated.

This apparatus is shown in the drawing, namely:

Fig. Ι a longitudinal section and

2 shows a cross section through the apparatus,

3 shows a plan of the upper part of the furnace,

Fig. 4 is a sectional view, and

FIG. 5 shows one according to c - d in FIG. 6, while

Figure 6 is a plan of the lower part of the furnace.

The strontium carbonate, which is formed in tubes or in some other way, is first poured into the retorts N installed above the actual decomposition furnace A. These retorts are located in a shared furnace M, which is heated by the special furnace O. The retorts are heated to red-hot heat, and this heat is transferred to the carbonate fittings and gives them the necessary strength.

These retorts serve, so to speak, as a funnel for the furnace A below, in which the decomposition of the strontium carbonate takes place.

On both sides of the lower part of this furnace are the superheaters C C. heated by the furnace BB . These are horizontally mounted cylinders made of refractory material, which are filled with fragments of the same material. The steam to be superheated enters through the pipe F to the outer end of the cylinder, passes through these cylinders and overheats itself on the glowing fragments contained in the cylinders, in order to finally flow into the decomposition furnace A at the other end through the openings G made there.

The furnace A, which is empty at the start of operation, must be heated to red embers before the carbonate is poured in; using the superheated steam for this would take too long and would be too cumbersome. The furnaces BB are therefore connected to the furnace A through the ducts E , so that the hot gases from these furnaces flow through the furnace A , and since the retorts N of the furnace M are open at the top, they form a kind of chimney through which the gases escape after passing through furnace A.

When the furnace A has been brought to a sufficiently high temperature, the carbonate begins to be charged into the furnace through the retorts JV; but instead of first filling in the carbonate pieces, which would break if they fell on the floor of the furnace, natural strontium carbonate is first introduced in large pieces and the furnace is gradually filled with it, allowing the gases from the furnaces BB to pass continuously through furnace A. .

When the furnace A and the natural carbonate introduced into it are sufficiently preheated, the channels E are closed and the channels QQ opened, through which the gases then pass during further operations in order to heat the evaporation pans RR , in which the after precipitation the saccharate remaining mother liquors are evaporated.

After it has been preheated in this way, the still moist carbonate fittings are poured into the red-hot retorts N and the steam, which is superheated in the cylinders C, is let into the furnace Ä? flow in, which then brings about the transformation of the carbonate into oxide. In the case of natural carbonate, this conversion is in most cases a very incomplete one, nevertheless the strontium oxide formed is gradually taken from the furnace through the door H attached to the bottom of the furnace and brought onto the carriages /, which then on the rails J from the furnace Can be extended. As much strontium oxide has been removed from the furnace at the bottom, the same amount of carbonate is refilled at the top, and the carbonate formed in the cylinder and previously preheated in the retorts N , which was created during the precipitation of the sugar, is refilled. The preheated carbonate removed from the retorts N is replaced by new fittings so that the retorts N always remain filled. These retorts are closed after each loading.

When finally the whole first batch of natural strontium carbonate is put into the furnace is removed and in this there is only mass originating from precipitated carbonate The machine is in normal operation, and then it only gets very good a little undecomposed carbonate come out of the oven.

The natural carbonate filled in first, which was only incompletely decomposed, is treated with boiling water so as not to remove the soluble strontium hydroxide to separate soluble undecomposed carbonate; the latter is then mixed with the artificial carbonate and then placed in the furnace with it.

The progress of the operation can be observed through the viewing holes KK made in the furnace A. The released carbon dioxide escapes through the pipe L.

The furnace O of the furnace M can be charged from the platform P.

Claims (1)

The steam required is generated by the extracting machine steam from the sugar factory delivered. The mother liquors remaining after the sugar is precipitated always contain strontium hydroxide in excess, which partly crystallizes out when the lye cools. When working with beet juices, the amount of these mother liquors is very considerable ,. which requires a large number of crystallization vessels to cool the alkalis and to crystallize out the hydroxide power. The ease with which strontium hydroxide, which contains 9 molecules of crystalline water Crystallized by simply cooling down, the inventor was able to manufacture an apparatus with the help of this this! crystallization very quickly and avoiding the mentioned inconveniences is going on. This apparatus is shown in Fig. 7 and consists of two flat pans A and B, the former of which is inserted into the latter in such a way that a free space remains between the two on three sides. These pans are slightly inclined so that hot mother liquor flowing into pan A at C flows to the other end of the pan, where it is cooled and, after the strontium hydroxide has crystallized out, flows off through pipe D. In the vicinity of the tube D in the pan A there is a perforated partition E, which holds back the crystals in A. This partition is provided with an evacuation door, which is also perforated. Cooling water is passed through the pipe H into the pan B , which flows in the opposite direction of the mother liquor in A due to hydrostatic pressure in B and exits at I. The mother liquor can be completely drained from A through the pipe F. G is a manhole for removing the crystals from A. As can be seen, this apparatus works continuously. PATENT REQUIREMENTS: An apparatus to first heat the natural or artificial strontium carbonate resulting from the decomposition of the saccharate to red glowing heat and then to expose it to the action of superheated steam, for the purpose of producing strontium oxide, consisting of the decomposition furnace A in connection on the one hand with those heated by the furnace O Retorts N for preheating the carbonate on red embers, on the other hand with the steam superheaters C, which are heated by the furnace JS. In this apparatus the use of the hot gases withdrawn from the furnace BB, on the one hand, when the apparatus is put into operation to heat the decomposition furnace A to red embers, and, on the other hand, after the apparatus has been started up, to evaporate the mother liquors resulting from the sugar production.
The apparatus characterized by patent claim 1 in connection with the pans R heated by the withdrawing hot gases from the furnaces BB for evaporation of the mother liquors and the apparatus shown in FIG. 7, consisting of the two pans A and B placed one inside the other, for cooling that of J? coming mother liquors and crystallizing out the strontium hydroxide contained in them, For this purpose 2 sheets of drawings.