DE1733C - Innovations in the manufacture of sodium, mono- and bi-carbonate according to the ammonia process and the associated apparatus - Google Patents

Description

IMPERIAL

PATENT OFFICE.

Certain improvements are noted here which are made in a system of apparatus and chemical processes exist, through the application of which regular and safe results can be achieved in soda production according to the ammonia process. Become the same in the following described separately according to the various stages of this production and illustrated by the accompanying drawings.

I. Distillation of the ammonia.

About that in the ammoniacal liquid, which is formed by the sodium bicarbonate was separated to distill off the ammonia contained, I have two new arrangements in met my still, which in a practical way the. necessary conditions fulfill. These are:

1. To process large quantities of liquids continuously and with ease.

2. First of all, the entire quantity of carbonate of ammonia from the ammoniacal liquid take off.

3. The use of as little lime as possible, as well as it from the oven, sometimes still comes unfired, with its impurities, as well as avoiding too violent and harmful gas development as a result of too sudden a reaction between "lime and liquid.

4. The best use of the heat, which is obtained from extinguishing the lime and the waste steam of engines is obtained.

These results are obtained in the following way:

i. Disposition.

This is illustrated by FIGS. 1, 2 and 3 of the accompanying drawings.

Fig. Ι is a vertical section,

Fig. 2 is a horizontal section,

Figure 3 is a top plan view of the false or false bottom of the distillation columns.

The apparatus consists of the column A, which is used to distill the liquid without lime, and of the stills BB ¹ B ^ B ³ , which are used to distill the liquid with lime coming from the column.

The four bubbles (there can also be more or less) are connected to one another by a distributor C , whereby one is able to isolate one or the other bubble for filling, emptying or cleaning, without interrupting the distillation the other.

The steam required for the distillation is taken directly from the engines, when it escapes after the work has been done and reaches the distributor through pipe T. It first enters the filled bladder B through pipe T ¹ , escapes through pipe T ' ² , in order to return to the distributor, from where ^{it goes through the pipe T "3} into the second and also into the third bubble, so that the new vapor comes out of that bubble first

the ammoniacal content of which the last traces of ammonia must be removed.
After the vapor / bubble has left B ² , it goes through pipe V into column A and causes the distillation of both the free and the carbonate of ammonia.

The latter, upper section P of the column acts as a condenser for the water vapors that are entrained, so that the ammonia can escape through tube A ² alone. Instead of water, the liquid to be distilled is expediently used in the serpentine tube S r in order to preheat it. A regulator is placed above compartment P, which is set into action by the change in temperature.

This apparatus consists of a float F in a reservoir into which only a little water is added. The gas evolved during the distillation heats this little water, and when it is sufficiently heated the float will sink, act on the inlet valve G , open it, and let water or ammoniacal liquid enter the coiled tube. The regulator can also regulate the flow of steam into the still through the action of the float on a Papillon valve. In any case, its use is of great importance, for the condensation of the water vapors in the brine, that is, their dilution, must be avoided.

When the liquid to be distilled comes out of the cooling coil pipe, it is passed through pipe L into the column and flows out of this through the lower pipe / into the previously emptied bubble B, the basket of which has been freshly filled with lime.

You can use lime that has already been slaked for this purpose. Lime in whole pieces as it comes out of the oven is preferably suitable, whereby the heat released during extinguishing is used; it is put through the opening S into a cylindrical basket, in which all undissolved and impure parts remain. When the boiler is emptied, the residue in the basket is removed through door J.

This allows the ammonia to escape from the rising liquid, which attacks the lime, takes place only gradually and can never be dangerous; because as soon as the pressure is too strong in the bladder to be filled, the liquid can be caused by the internal pressure no longer penetrate the device.

When the lime is extinguished, heat and steam are generated, which can be used in the column and the pipes V and V ¹ serve to transfer them.

Also to be emphasized is the use of false or intermediate trays X in the absorption column Fig. 1, which are similar to an inverted funnel, the convex part of which is perforated and toothed or jagged on the periphery. Thanks to this shape, complete heat absorption is achieved.

When the lowest section O of the column has received the necessary amount of liquid for a bubble, lever i acts on valve K and prevents further inflow of liquid; a standing glass attached to the side shows the degree of filling.

M are overflow pipes, N pipes for the rising of the steam and ammonia. Y is a safety valve, Z are blow-out taps for the bladders or kettles.

2. Disposition.

FIGS. 4 and 5 belong to this.

Fig. 4 is a vertical and
, Fig. 5 is a horizontal section of the still.

The installation of this apparatus allows uninterrupted distillation in one and the same column. It consists of two parts, an upper A and a lower B. The upper part, consisting of eight chambers, is of the same construction as the column shown in Fig. 1, but can also be constructed like the lower part B, consisting of twelve chambers which is used for distillation with lime.

The containers P pi P ^ p $ are each provided with a second grid-like or grate-like base G. see and serve to take up the impure caustic lime for the distillation. If the containers are to be emptied of the impure residue or to be refilled with fresh caustic lime and have to be shut down for this purpose, they are excluded from circulation ^{with the help of the taps rr 1} r ^2.

When the liquid has entered the lower section A ^{a of} the column, that is, after all the carbonic acid ammonia it contains has been distilled off, it flows into the relevant container P where the tap r is opened, is saturated there with lime and passes through the cock r ¹ in the column section B, Fig. 4. This consists of a cylinder which is divided into several chambers. The bottoms c causing this division have an opening f in the middle; upwardly bulging perforated shelves F, toothed on the periphery, rest on them, the position of which can be regulated by the side bars T. The liquid, saturated with lime, gradually descends through this part of the column B , and is completely distilled through the tap R.

The gases and water vapors developed in the lime containers P escape through the

opened taps r ² and are used in the upper column compartment A for the purpose of distillation. As a result of the height of the overflow pipe g , the lime resting on the ground G is continuously bathed and dissolved by the ammoniacal liquid. But if the action on the lime becomes too vigorous, so that the evolved gas and vapors can no longer ^{escape sufficiently through the open cocks r 2} , the liquid is dammed back so far by the strong internal pressure that only a small part is dammed the lime is bathed. The dissolution of the same thus takes place automatically.

The steam required for the distillation in part B of the column is introduced through the opening ST, and so that the apparatus works regularly and well, it is advisable to introduce the steam intermittently and radially.

Whichever still is used, it is always beneficial to use the vacuum, to reduce the vapor tension required for distillation. The same can happen known way, but I prefer the water piston pump.

Between the ammonia absorption apparatus and the pump or those generating the vacuum Apparatuses are peculiar washing apparatuses, which are described below will.

The main innovations of the distillation system described are as follows:

ι. Two stills in their related Composition and its context as described and illustrated.

2. The use of the means and facilities described and illustrated in order to achieve the To treat liquid with caustic lime.

3. The use of the heat that develops during the slaking of the lime for distillation.

4. The use of vacuum during distillation by setting up intermediate recipients.

5. The use of the steam from the engines to distill the ammonia.

6. The introduction of the liquid to be distilled when the gases are withdrawn from the coiled tube or another cooling device.

7. The application of the. perforated and toothed plates, as well as

8. The arrangement of the described and illustrated regulator to the entrainment of the To prevent water fumes with the ammonia gas.

II. Clarification of the distilled liquid. The liquid completely distilled off can to drain into the canal. However, as contained in the same calcium chloride and sodium chloride these two salts must be obtained and separated. For this purpose the liquid becomes larger Container filtered or decanted.

I have now invented a continuously acting clarifier (decanteur), which one occupies a small space, the liquid clears very well and a regular and continuous one Deduction of the separated compact lime permitted.

This decanter is shown in FIG. 6. The distilled liquid is passed into the central tube B through tube C. The steam escapes through the forge D, while the liquid first flows into the cylinder A , which is closed in the shape of a funnel at the bottom, then rises to the drain E and drains through the pipe F. The lime which accumulates at the bottom of the apparatus is removed by the action of the scraper G by means of the gear H through the tap J.

A cone K , which can be regulated by the lever M by means of rod N , is arranged so that the incoming liquid does not stir up the precipitate of lime that has already formed.

This apparatus can of course be modified in various ways without the peculiar. to deviate as a newly claimed being, which consists in the fact that:

ι. the newly introduced liquid between the surface of the existing liquid and the bottom of the apparatus comes to stand in such a way that the liquid already treated must rise and flow cleared, and

2. The precipitate must collect at the bottom of the apparatus and through a Opening can be deducted.

This apparatus can not only be used for decanting the distilled, but also for others Liquids found in soda production can be used.

III. Preparation of the ammoniacal
Alkalis.

The best location for an ammonia process soda factory is above or in the Near a salt spring; I take it especially with regard to the preparation of the ammonia lye suggests that the saline solution is taken from such a source or well. In the other Trap you have to dissolve table salt in water and treat like a natural, saturated salt.

It is well known that lime and magnesia, when present in salt water, pass through carbonic alkalis are precipitated, and furthermore by heat and movement of the liquid the withdrawal and withdrawal of the same is promoted; but is alone with these means the salt water has not yet been cleaned. I have found through exact experiments:

ι. that if one lime is an impure one magnesia-containing sols are added, the magnesia is replaced by the lime and excreted. The lime compound formed is then easily precipitated by carbonate of ammonia;

2. That magnesia salts can only be completely eliminated if carbonic acid is used Ammonia used in excess;

3. that an equivalent amount of the pure brine is obtained after the named salts have been precipitated Sodium chlorine must be added because the presence of the lime and magnesia salts Soole prevents the amount of sodium chloride from being absorbed, which is used to manufacture soda is required.

The first two facts led me to factory-make naturally unclean sools to purify and, according to the third fact, to justify my procedure.

Since most of the carbonate alkalis are expensive, I use them in my soda manufacture produced carbonic acid ammonia. I have two of the above Established procedures, of which I give preference to the second.

First procedure.

Lime is added to the impure brine and the mixture is stirred for a while, during which the magnesia salts are displaced by calcium salts and are immediately precipitated when the soole already contains lime salts, or, like the dissolved caustic lime, they are easily replaced by carbonic acid To excrete ammonia. This operation is best performed in two vessels, by draining the liquid mixed with lime from the precipitate formed and pouring it into treated in a second vessel with carbonate of ammonia. One must be careful observe that the ammonia to be used does not contain more than one equivalent Carbonic acid is connected. After cleaning is finished, the ammoniacal Lye brought to the required saturation by adding sodium chloride.

Second method.

Here the cleaning of the salt water takes place during the preparation of the ammonia solution carried out.

The apparatus which I have invented for this operation are illustrated by FIGS. 7 and 8.

The salt to be saturated with ammonia is contained in one of the vessels R or R ¹ . A is the apparatus for dissolving ammonia (Dissoiveur). Assuming that one wants to saturate the brine contained in R with ammonia, then one brings R into connection with A by opening the taps r and r ¹ . The ammonia comes from the distillation through pipe T into dissoiver A, and this pipe opens into a perforated intermediate floor F. A flow arises in the apparatus, so that after a while all the liquid from vessel R passes over to A , and the ammonia absorbed.

T ^] is a pipe for the discharge of the ammonia-laden gases that develop during the operation and are collected in a washing vessel. In addition to this washing process, I use the vacuum mentioned in I. with advantage. The necessary movement of the liquid is brought about both by the absorption of the ammonia and by the agitator W. When the latter is stopped, the precipitate forms at the bottom of the vessel. The necessary circulation can also be brought about through the device shown in Fig. 9 by activating the screw H , which moves at a rate of several hundred revolutions per minute in the cylinder C which is connected to the absorption apparatus and the vessel containing the salt water through the mouth t and f ^! communicates.

The necessary heat is produced by the absorption of the ammonia, as well as by the serpent S. I then restore the soole to the required level of saturation.

V is a tube through which purified saline is brought into the absorption apparatus during surgery. The supply and measure thereof are regulated by a wheel m divided into compartments, and its dissolution is promoted by the moving liquid.

With the device just described for the correct dosing of the ammonia, it is necessary that the cocks or valves be closed each time the contents of one of the containers R or R 'are saturated with ammonia, in order to be able to continue the saturation of the other. The operation of dosing ammonia can also be carried out automatically, in which case the apparatus must be based on the increase in volume of the liquid and not on its tightness, as the latter would lead to fallacies from the variable amounts of carbonic acid introduced. I have found a means of making direct use of the property of the increase in volume of the pure brine, which is determined by each corresponding dose of ammonia absorbed. For this purpose I connect the Dissoiveur A with two vessels, one of which is used for receiving and measuring the salt water, and the other for drawing off the appropriate amount of ammonia liquid of appropriate concentration. To achieve these results

I turn two vessels and an apparatus with a float. When the ammoniacal liquor in one of the containers has reached a certain level, the float in it will cause the ammoniacal liquor to be emptied through the apparatus. During this emptying the float falls and at the end of the fall causes the opening of a valve in the other vessel, whereby the required quantity of prepared pure brine is admitted into the dissolver A.

Fig. 10 shows such an apparatus.

A is the dissolver; X is the salt water reservoir fed through tube t from a constant level tank. X ¹ is a reservoir into which the ammoniacal salt water flows through pipe f ¹ ; s and s ^x are two double-seat valves. F is a free swimmer on the bar or similar.

The effect of this device is easy to understand. When a certain amount of ammonia has been absorbed, the liquid rises in the reservoir X ¹ and in the dissolver A, whereby the float F lifts the rod and simultaneously opens the valves s and s ^{1 by means of a lever.} By lifting the valve 5 ¹ the inflow of the salt water into the vessel X is prevented and the entry of the certain amount of brine contained in this reservoir into the apparatus A through the pipe T is made possible. At the same time, the connection between X 'and A is ^{closed by valve S 1} and the ammoniacal liquor is drained off through pipe J. The outflow times are regulated in such a way that the salt water of the vessel X has already completely passed into the dissolver A before the vessel X ^{1 is} empty, whereby the swimmer, pulling the rod ο with it, restores the original situation.

The double lever L associated with this device carries rolling weights q and ^ ¹ on both arms, by means of which the valves are firmly held in their seats. These roll from one end to the other when the lever is lifted and dropped. Instead of these weights, one can also use mercury for the same purpose, as can be seen from FIG. 11.

When the dosing is over and the lime together with the magnesia has accumulated at the bottom of the vessel R, Figs. 7 and 8, I drain the still liquid sediment through the pipe L into the clarifying vessel D. The clarified liquid runs off in the U pipe. The precipitate, loosened from the funnel-shaped bottom by the action of the scraper M , rises in the pipe J and is drawn off through the tap t in order to further recover the ammonia therefrom in a still.

The ammoniacal liquor can be driven from the vessel R or from the automatically operating measuring and dosing apparatus into the clarification vessel D and from there through the pipe L ¹ into the filter B , or the lower liquid can simply be driven into the clarification vessel and the upper one through pass the tube N into the filter.

When the clarification is complete, it is always useful to dense the ammoniacal liquid through To filter substances under a pressure of several atmospheres in order to remove the suspended, to remove the finest particles.

Fig. 7 shows my cylindrical filter B. Inside the same, in a second perforated cylinder 0, there is a tight sack which is removed and replaced by another as soon as it is filled with sediment. There must always be two or more such filters in operation. It is also possible to filter from the outside to the inside by enclosing the inner cylinder o with a sack and removing the sediment through the lid d . The ammoniacal liquid is passed from the filter into the refrigerator C. This consists of two snake tubes, one inside the other. The cooling water can be circulated through the inner tubes as well as through the annular space.

In the case shown in Fig. 7, the ammoniacal liquid enters through the mouth h and through the mouth /? ' while the cooling water from fliefst, wherein it passes through the entire cycle in the annular space through the inner iron or lead pipe \. It will be appreciated, that the tube bends \ ^x serve the inner tubes \ with each other to be connected, which cause the outward tubes Z Z T-pieces. ¹

The innovations attached are the following:

1. The cleaning process, which is essential in the use of carbonate of ammonia consists of the previous displacement of the magnesia salts by calcium salts takes effect.

2. The totality of the operations of the second process; the purification of the soole associated with the absorption of ammonia, with or without automatic measuring apparatus, with or without filtration, with or without cooling the liquids.

3. The addition of table salt to the salt which has been purified from magnesia and lime salts.

4. The purification of the previously formed soils by the application of ammonia in order to to precipitate the salts obtained in suspension,

after which a simple clarification and filtration of the brine has to take place.

5. Automatic ammonia dosing.

6. The absorption of ammonia in a recipient by a circulation system.

V. Carbonization of the ammoniacal Lye.

The method is successful if a complete reaction of the carbonic acid is achieved.

To the mechanically exerted pressure, to the manifold distribution of the gas, to the significant The height of the apparatus and the manner in which the ammoniacal liquid is introduced must first be treated with carbonic acid.

I have found that the warming which arises from the reaction of carbonic acid ammoniacal lye is produced, is not the same in all periods. It is in the beginning intense, then continually diminishes or even disappears, so that when the operation is divided into two periods, the warming almost exclusively during the the former occurs, and without the use of any special means the carbonization of the ammoniacal ones The fluid remains quite incomplete, while the completion of the reaction presents great difficulties Overcoming has not yet succeeded. The essential condition is that this reaction is quick and to carry it out perfectly consists in using the lowest possible temperature. I have found means by which the harmful warming in the first part of the Reaction is limited, while later the reaction is carried out cold.

One becomes the importance of this invention which allows me to use my powerful absorbents easy to grasp without letting the warming act. The advantages that mine Apparatus offer, give the designated division the operation is of even greater importance in relation to the cooling Quantities of liquids than in relation to avoiding loss of ammonia. These Combination is carried out as follows:

Pure carbonic acid, the generation and source of which I will describe later, is described in the upper section of the distillation column, in which it is mixed with the caustic ammonia to form carbonate of ammonia, which is transferred to a dissolving apparatus and absorbed by the brine.

V. Generation of carbonic acid.
The carbonic acid required for my manufacture is obtained by calcining carbonate of lime in ordinary lime kilns. It has been recognized as advantageous to use a purer carbonic acid in certain regular intervals, and it is known that hot steam, directed on red-hot lime, ran a pure carbonic acid. I take advantage of this behavior by performing my own operation on the lime kiln. At this end I direct a jet of steam into the heated lime kiln at certain intervals, either through the lower openings or at a certain height or from above, in which case I suck up the carbon dioxide from below. The jet of steam introduced must be very strong in order to prevent the air from entering the furnace, which, moreover, can be well closed by doors. The pure carbonic acid produced in this way in the interstices is used before the ammoniacal liquor leaves the carbonic acid absorption apparatus in order to achieve complete carbonization of the liquor. Before using the carbonic acid, it is washed and cooled in an apparatus similar to that which I use for washing the gas coming from the absorption columns and which I shall describe later.

VI. Cooling the carbonic acid.

The cooling of the carbonic acid is caused by expansion during work (power acidification) obtained, where you can bring the temperature down to a few degrees below zero. It is important that the carbon dioxide does not lose this work.

For this purpose I use a second pump on the machine, either before or behind the pressure pump, and connect the two pistons to one another in such a way that the Piston of the supplementary pump acts simultaneously with that of the driving force. The carbonic acid gas is compressed as much as necessary in the pressure pump and in the auxiliary pumps mentioned transferred, where I let it act as a driving force by virtue of its expansion, up to the voltage suitable for use in the absorption columns. The cooling off thus happens almost free of charge.

What I particularly emphasize here is essentially the use of an apparatus which between the machine compressing the carbonic acid gas and the absorption column, in which the same acts on the ammoniacal liquor, is arranged.

VII. Ingestion or absorption of the

Carbonic acid.

The improvements in this direction consist in the fastening of the perforated plates or wrong floors in the absorption

column so that they cannot get into an irregular position. I have found that if they are precisely horizontal they can have a certain amount of leeway in the vertical direction. This purpose is achieved by attaching guides (see Fig. 12). The same can also be obtained, as with F in FIG. 13, by means of a central rod A in a fixed position. This rod has a lifting or hand screw at the upper end, by means of which the intermediate shelves can be lifted. Fig. 13b shows such an intermediate floor on a larger scale.

On that part of this apparatus where the liquid enters, I have attached flaps R, which open inward, so that in the event of an accident the liquid cannot escape from the column. I also use the same flap on pipe E, Fig. 13, which is used to introduce the gas.

VIII. Dissolution of the chlorammonium.

The great task in the manufacture of sodium bicarbonate consisted of cooling of the apparatus or in the prevention of the heating of the liquid, thus as much as possible rapid and complete reaction could occur. This method, however, which is favorable for the manufacture of the sodium bicarbonate, caused by its intensity Effect the formation and excretion of chlorammonium crystals, which, with the Sodium bicarbonate mixed, cannot be separated from it by ordinary means. This result becomes even more unfavorable if one uses sodium chloride in excess.

The means of countering this evil consists in an appropriate application the warmth. Indeed, the solution of the chlorammonium takes place through the action of heat much faster than that of sodium bicarbonate, hence by increasing the Temperature all chlorammonium and only traces of sodium bicarbonate can be dissolved.

It goes without saying that the use of cooling means for the reaction and the application separate from heat to prevent the chlorammonium from crystallizing must be. In my production I use two different temperatures two different purposes, namely in the absorption column, in which I introduce the carbonic acid gas instead of from below at a certain height and at the bottom Place a coiled pipe in the lower section to warm the liquid. A better one Method consists in heating the liquid in a separate apparatus where one it can be set in motion more easily by mechanical means and thereby a transmission the heat on the reacted liquid is avoided.

IX. Filtration.

In a large company, multiple and interrupted filtrations are to be avoided. I have made improvements in the construction of my continuous vacuum filter, which can be seen from FIG.

Any amount of the liquid saturated with the bicarbonate is passed from the columns through pipe K to the filter by opening taps X and Y. I introduce the water required for washing through the L pipe. The improvements are as follows:

1: To uniformly spread and wash the sodium bicarbonate on the filter, I use a rotatable perforated tube ^ which extends through the side outflow the reaction caused by the liquid rotates.

2. I use a water piston pump to generate the vacuum. I give her a new determination to which she is particularly suitable, since almost all of them are through her harmful spaces are suppressed.

I also use them to wash the by sucking in air or gas entrained ammonia and thereby protect the metal fittings of the pump, which otherwise they will soon be attacked by the gas. The washing water contained in the pump can be salt water, because the ammonia to be washed is either carbonic or caustic ammonia, which can dissolve in salt water before the latter in the ammonia dissolveur is directed. In the constructive details this pump has the following improvements, which are shown in Figs.

A is the pump cylinder, P the piston, B and B ¹ are water tanks, between which the piston moves. CC are lids, R pressure valves or flaps, 5 suction valves, O taps to let in the water. What should be emphasized here is the disposition of the valves or flaps, which, due to their position on the lid, do not cause any disturbance in the movements of the water or in the relative dimensions and shape of the water tanks. This pump otherwise functions in the same way as all the others.

In the reservoir Q., FIG. 14, ^{the vacuum is generated by the pipe F 1} and in this reservoir the liquid coming from the filter is admitted through the pipe W , from where the liquid is then passed into the distillation column. Two or more of these separation reservoirs are maintained alternately in operation.

3. In order to use a large number of taps, as well as the one I had previously

To avoid using the distributor during the filtration process, I have a continuous one Filter was invented, which is shown in FIGS. 18, 19 and 20.

The filter apparatus consists of a round reservoir A , divided into any number of compartments, in the case shown in the drawing into eight. Each section is covered with a grid or a perforated plate G, on which a suitable filter material, such as flannel, canvas, etc., and over which a wire mesh is placed for better retention. These compartments extend into the foot of the reservoir and are connected to the interior of the reservoir base forming a box C through openings in the base plate P. This box C has three sections; Division c ¹ is intended to contain the liquid descending in divisions A ¹ A ' ² and A ^{s , c 4} the liquid descending in A * and c ⁵ the liquid descending in A ^& A ⁶ and A ^1. There is no division under A ^8.

The reservoir A can be rotated in the indicated direction of the arrow on the cover plate P ^{1 of} the base; this rotation is intermittent and is carried out in such a way that, with a complete rotation of the reservoir A, each section comes to stand once over the point at which there is no free space, so that each section is gradually led to the determination which the related location is conditional.

I shall now describe the function of the apparatus in the position shown in the drawing. Compartment A ¹ is supplied with the chlorammonium containing the sodium bicarbonate by means of a separator which is connected to a vacuum pump through a perforated tube connected to the tube T. The outflowing liquid reaches c ¹ and is emptied through the pipe t by means of a separator connected to a pump, together with the liquid coming from A ² and A ^s , which sections were already filled earlier than they were in place of A. ^x were. While in section A ² the bicarbonate on the filter is supposed to dry off to some extent, in A ^{s, by} means of pipe T ^1, that in R ³ and i? ⁴ accumulated water, what in A * for leaching dieme and through c ⁴ and pipe t ^l to R ^s and i? ⁴ arrived. In A ^ , by means of pipe T ^2, the water stored in R 'and R ² is added, which in A ^ A ⁶ and A ^{1 was used} for washing and leaching and through c ⁵ and pipe A " to R ¹ and R ^2. In A ^& the last washing with pure water is carried out by T ³ , coming from R. While A ^e and A ^{1 are used} for drying, the bicarbonate is emptied in A ^s . This can be done by workers using crutches, or automatically using a chain of cups Or else take place in such a way that the partitions 5 above the filter surfaces are removed and the bicarbonate is emptied through a plowshare-like fixed crutch.

During the rotations which take place at certain times, each of the sections comes to the point A ', is precipitated here with the liquid coming from the absorption column, of which the bicarbonate remains on the filter, and, with repeated rotation, arrives at the points where the carbonate is systematically washed, dried and emptied. The movement is mediated by the gearbox ρ and the pulleys χ and x ¹ , one of which is fixed, one is loose. For this purpose, the reservoir has a wheel rim E.

The vacuum required in the containers R 'to R ^A to suck up the washing or leaching water is generated by a pump connected to pipe V. The water for container R comes through pipe V ¹ . The containers R ¹ to i? * Are arranged in pairs so that one can fill up while the other is being emptied. The valves can just as easily be set up as self-acting by means of floats instead of for manual operation. It goes without saying that the shape and dimensions of my filter apparatus can be changed; the essential thing about it is its continuity and the simultaneous care of all its parts in the various stages of operation.

Without departing from the essence of this apparatus, I have a different construction and arrangement brought into execution, which is shown by Figs. 21, 22 and 22b. Here the apparatus consists of a cylinder that rotates around its horizontal axis.

X. Reduction of the straightness of the soda.

It is important in trade that soda be manufactured of varying degrees of accuracy, and it is customary to mix table salt with the soda at this end.

I achieve this result when washing the soda in my filter by adding Soole or dissolved sodium chloride of such a tightness that should correspond to the desired degree of stability of the soda. If I, therefore, salt water of 25 ° as used to, I get a soda from 8o ° and with salt water at 18 ⁰ as a soda of 84 ° Descroizilles. The same result can be achieved if one mixes proportionate amounts of pure water with salt water that is always of the same degree of accuracy.

XL representation of sodium bicarbonate.

The preparation of bicarbonate as a commercial commodity is of great and practical importance. The matter has not hitherto been given the necessary attention. One saw in it a simple drying process and those who are concerned with this branch of soda manufacture do not operate with great care Quantities. The treatment of this salt is fraught with difficulties Drying at a temperature not exceeding 59 ° C, with a tendency to cake.

I have invented two devices, both for drying the bicarbonate and for Conversion of the same into its monocarbonate are suitable. The facility consists of that one can work on large masses by means of a warm gas, the temperature of which is perfect can be regulated acts.

The apparatus is shown by Fig. 23 and has a heat regulator on the front. The hot air enters this through the tube T and shares more or less heat with the water contained in the reservoir, whereby the float F is caused to rise or fall. When the warm gas has a too high temperature, the float lowers and raises the damper, di flap r, by means of the lever £., Flows whereby cold air and to heat to the required temperature returns before passing through the tube T ¹ comes in the drying box.

ι. Apparatus. Fig. 24. When the sodium bicarbonate has been appropriately divided by shaking in a double grid, it is placed in a vertical or horizontal cylindrical container in which an agitator is turned very quickly, whereby the salt is very finely divided and, by the influence of a stream of warm air, in The form of a fine powder or dust accumulates in a dried chamber. A is the disintegration vessel into which the bicarbonate to be dried is thrown. In it is a shaft N with a scraper M, by means of which the salt is brought through the opening c to the cylinder C. In the middle of this cylinder is a vertical shaft S with wings U, which rotates very rapidly and in the process beats the bicarbonate to powder, while it comes into intimate contact with the appropriately heated air which flows in through the tube T ^1. The bicarbonate dried in this way settles in the container E , from where it is emptied through the door G, while the air escapes through the pipe H. Horizontal dry rooms have waves with floating wings.

2. Apparatus. Fig. 25. It has a similar device to one which is used to purify the luminous gas. However, the application is completely different. While the gas is acted upon by a chemical action, in my process solid matter is subjected to the physical action of heat. Fig. 25 shows such an apparatus, which consists of a box A with a wire mesh or perforated sheet metal base B fastened at half its height, on which the bicarbonate coming from the filter is spread. The correspondingly warm air can be fed into the box from above or below through the tubes T or T ^. If several such apparatuses are used, it is advantageous to combine them for loading and unloading by a distributor.

XII. Manufacture of sodium monocarbon at s.

The bicarbonate has to be decomposed for the manufacture of common soda (monocarbonate) and be calcined. These two operations can take place in one and the same apparatus or can also be carried out separately. The ones made in the process and on the apparatus Improvements are as follows:

A. Breakdown of the sodium bicarbonate.

The decomposition can be carried out in both apparatuses, Fig. 24 and 25, by means of hot, dry air, or by means of superheated steam. But I have found that it is more common Steam extracted from a generator can be used not only for leaching but also for breaking down the bicarbonate can. I prefer the apparatus, Fig. 25, because several of them are used together so that the steam not condensed in the first apparatus condenses in the following and can be fed into any apparatus by attaching a distributor can, which allows separate loading and unloading.

Fig. 26 shows, in vertical section, one of the numerous devices by means of which this part of my invention can be carried out. ABCD are the vessels for decomposing bicarbonate, any number of which can be used. O is the distributor to which the steam is fed through the pipe T and which allows one or more vessels to be isolated for filling and emptying at the same time. If A and D are isolated, the steam flowing into the distributor O will pass through tube t into the upper space of B , penetrate the bicarbonate contained therein, then back through t ¹ into the distributor, and from there through i ² into the upper space of C, then go back through i ³ in the 'distributor to finally go through

Pipe ί ⁴ to go off into the distillation column because of the use of the carbonic acid gas.

The heat of the steam is sufficient to decompose the bicarbonate. Due to the condensation of the The latent heat of steam is used for this decomposition in such a way that I achieve an incomparably greater effect than if I were to use an uncondensable gas or superheated steam. That of the ordinary Condensation water obtained from steam is used to wash and leach the sodium bicarbonate.

By chemical means, the decomposition of the bicarbonate can be carried out in the following way by using a basic substance which can be mixed with the excess of Carbonic acid combines and forms a monocarbonate. For this purpose I use Ammonia gas, which I add to the sodium bicarbonate in the filter or in the apparatus, Fig. 24 direct, or I bring the latter into an ammoniacal lye. After decomposition . the liquid is separated from the monocarbonate formed by new filtration and washing, the apparatus is to be kept warm accordingly. With this method one has the advantage that this is done simultaneously with the decomposition of the bicarbonate, a preliminary carbonization of the one to be used afterwards Ammonia is achieved.

B. The calcination of soda.

When the bicarbonate has been broken down and purified from ammonia, the monocarbonate obtained must To be calcined what I am in a rotating furnace, which is a melting of the soda not allowed, gentleman. My stove is conical or cylindrical in shape, sloped and forward and open at the back. The more intense the fire, the faster I let it rotate, with the locomotion the soda is a larger one.

It is in longitudinal section, Fig. 27, and cross-section, Fig. 28, A, a rotatable cylinder, the interior of which is lined with fire-resistant bricks. The rotating movement is obtained by a gear mechanism E and e; it rests on rollers r and r '. The fire gases that warm it are generated in F. The fuel is introduced through the funnel T, the soda to be calcined through the inclined channel B. This accumulates in C and is emptied through door O.

C. Apparatus for decomposing and calcining soda.

If the decomposition of the bicarbonate and the calcination of the monocarbonate are carried out in a single apparatus which is heated from the outside, as shown in Figs. 29 and 30, it is necessary, especially when a high temperature is used, to continually scrape the hot inner surfaces of the kettle. I overcome the great difficulties that arise here by bringing the scraper D into an inclined position, with the obtuse angle forwards and with the acute angle backwards, so that they loosen the stuck-on soda with their cutting edge. The shape of this cutting edge depends on the surface S to be scraped, Fig. 31. F indicates the direction in which the arm C of the shaft B moves.

XIII. Various secondary devices.

A. Apparatus for the reduction of soils

the required degree.

The brine contains too little rather than too much salt and is subject to the process of manufacture still further dilution. However, it also happens that the ammoniacal liquor is too is salty and clogs the tubes with sedimentation of the salt. To avoid this Unfortunately I have invented an apparatus which the brine or the salt water on the the desired degree or tightness.

32 shows this apparatus. The salt water enters compartment A of the reservoir R through the mouth T and passes through the bent tube T ¹ into compartment B, from which it flows through O to the apparatus described earlier. In section A there is a float F, which rises when the water is too saturated and thus regulates the inflow of fresh fresh water from the tub S (at the same level) through the pipe V by means of the lever L. The tube V is divided by means of the rubber sleeve Y , whereby the necessary oscillations can take place. The water flows from this pipe into the funnel E and, going through the pipe Z , mixes in the pipe! T ¹ with the salt water. The fresh water comes through the mouth M into the tub S and the overflow goes through the mouth N from. This apparatus, by virtue of its great sensitivity, regulates the degree of salt water precisely.

B. Fluid pressure and metering apparatus.

This apparatus shown in FIG. 33 consists of a reservoir R into which the liquid flows through the flap C. The float F is lifted, and when it has reached the required height, it hits the disk r of the rod t, lifts it and thereby the valve S, which closes, and opens the valve S ^{1 by} means of the lever L, whereby compressed air or other compressed gas flows into the apparatus and the liquid is forced out through the flap C '. The float now sinks with the

Liquid, allows the rod to return to the previous position with the valves, ^{closing the gas entry at S 1} , opening the exit at S , and restarting the entry of liquid. The device is connected to a counter.

In the case of ammoniacal liquids, it is important to have the gas if it is the pressure apparatus Failing to wash or aerate while performing the operation Avoid losses.

C. Automatic scales.
For weighing the various materials and makes I have constructed my own balance, which is shown in Fig. 34. It consists of a balancing plate P, which is kept in equilibrium by the counterweight Q. A frame is attached to this plate P to support the shell P ¹ . The support takes place close to the rear end, so that the shell would tip over if it was not prevented by the locking hook e. F is a solid rod which, due to its rigidity, triggers the lock e when the plate P descends. The function is as follows: the material falls through the funnel T onto the bowl P ¹ and lowers the plate P as soon as the load precisely determined by the weight Q. is on the bowl. The locking hook e, which now sinks and rests diagonally on F , is pushed back by F and thus triggered, whereby the plate P ¹ tilts and the quantity obtained slides into the funnel T ^1. The plate P is now relieved and P ¹ is brought back to its previous position by the counterweight q , so that the locking hook e comes into operation again. The filling can now take place again. An attached counter shows the number of weighed quantities.

D. Wa s chap ρ ar a te.

The washing and cooling of the gases is necessary during different phases of the soda manufacture. For this purpose I use an apparatus X, which is shown in FIGS. 35 and 36 and which is supplied with salt water. YY show the passages of the gas. AA are overflow tubes for the cooling liquid, which enters the upper compartment at B in order to flow off at the lower mouth C. PP are inspection doors, Z are perforated panels, similar to those already described above in FIG. 3.

What I claim to be new and my invention I have in every section referred to in my description. I claim the apparatus and procedures described only insofar as they are concerned with the manufacture of soda according to the ammonia process (Solvay's Procefs) related. But I particularly claim that of me highlighted points in the different shapes, dimensions etc. which they without prejudice to the essence of my invention.

In addition 3 sheets of drawings.