DE920001C - Continuous horizontal purging process and system for its implementation - Google Patents

Description

Continuous horizontal slurry process and installation for its implementation The invention relates to a continuous multi-stage horizontal slurry process, which raw material with high selectivity (according to the criterion of the final grain speed in liquid) separates into two or more fractions and achieving one Achieving selectivity that matches those of the most exact vertical slurries reaches.

In the following, the degree of selectivity is the grain spread x20 / 8. This characteristic value x "/ eo is = i with perfect selectivity and grows as it decreases Selectivity.

While now with certain vertical slurry processes, z. B. according to Austrian Patent specification No. 165 36o, grain spreads x2oiso down to 1.4 can be achieved, these parameters remain with the currently known single or multi-stage horizontal slurry processes over 3.

Meanwhile, vertical slurries generally fail for reasons of flow Difficulties with - very small cut sizes.

The purpose of this invention is now in particular, for sharp selectors Slurry method (grain scatter x, / "under 2) the area of the separation fall velocities V., to be developed below 3 cm / sec (cf. the essays: »For uniform labeling der Trennschiefe ”, Montanzeitung Wien, Sept. 1951, pp. 163 to 165 and nChoix d'un coefficient unique pour caract6riser la pr6cision de s6paration, une proposition de normalization international «, Revue de 1'industrie min6rale, St. Etienne, December 1951, p. 479 to q.82). It is known, through multi-stage horizontal slurry, z. B. continuous decantation by means of several thickeners, whereby one usually works in countercurrent to save water, separating liquids from solids. Here, the sunken good z. B. by means of thick matter pumps from the bottom opening of one thickener is lifted into the inlet of the next thickener, with the fine overflow each thickener is fed into the feed of the preceding thickener.

With the help of known methods of this and similar types, it is well possible, e.g. B. pure liquids (grain diameter o) of certain grain sizes, e.g. B. to separate from all grain sizes over 0.02 mm, but this selectivity is such Procedure too small to carry out an actual grain sheath, d. H. so, not only, as in the example above, the coarse fractions from the original To free liquid, but also practically from all grain sizes below 0.02 mm.

According to the invention, with a horizontal slurry process at least two stages connected in series, each of which is fine and sinking material releases, the sediment suspended in liquid is conveyed up at least one step, a constant flow of the raised sediment suspension into the inlet of the the next stage passed, the overflowing river, however, back into the out Sinkings emerging from the previous stage are allowed to run back. Moreover, will in this sinking material flowing out of the original stage before it enters pure washing liquid in the pumping device (pump, compressed air / water lifter, etc.) or such washing liquid, which the fine material of the next but one Contains stage, according to the setting of the feed quantities of this washing liquid and from one, z. B. the first stage, the inlet of the next stage Sinking material suspension supplied to the outlet opening for the sinking material at least one stage a liquid flow in an ascending direction of at most 2o ° / o, allowed in a descending direction not exceeding 15 ° / o of the total mud flow will. The total slurry flow is the amount in liters per second which actually enters the stage in question.

The feed quantities mentioned are preferably adjusted so that at the outlet opening for the sinking material at least one stage the flow practically becomes zero.

With a four-stage horizontal slurry with countercurrent flow has z. B. shown that if the conditions according to the invention are strictly observed a grain spread xZOjao equal to 1.6 is achievable that this characteristic value with a Upstream of 20% or downward flow of 15% of the total mud flow rises to the value 2, with a further increase in the flow at the outlet points the steps, however, suffer a rapid enlargement.

According to the invention there is also a sharp division into three or more fractions obtained by first starting with the smallest of the desired Separation grain sizes (or separation rates) according to the above conditions muds, so a very small specific mud flow in the individual stages adjusts. As a specific slurry flow (liters per second and per square decimeter) the mud flow is understood, which is related to the unit of the mud area is. The horizontal section through the essential is again considered to be the mud surface Area of mud flow. In most cases the horizontal slurry can the slurry surface can be equated to the surface of the liquid.

The fine material from this first separation already constitutes a finished product while the coarse material is subjected to a further elutriation according to the above conditions is, the specific slurry flow now after the next separation grain size (or separation speed) is set, etc.

The invention also extends to an installation for implementation of the method according to the invention. The invention is illustrated by the several examples of horizontal slurry devices illustrative drawing explained, namely shows FIG. 1 shows a three-stage system for raw material fed in dry, FIG. 2 shows a four-stage system System for raw material introduced with liquid, each in view, partially cut, Fig. 3, purely schematically, a combined circuit of two three-stage systems for dividing the liquid fed raw material into three slurry classes and Fig. q. an example of a slurry body construction in the diagram.

The three-stage horizontal sludge system according to Fig.i has three equally large sludge bodies A, B, C, the z. B., as in Fig. Q. illustrated, each consist of an open-topped, pyramid-shaped container i, which merges at its upward-facing base into a short prismatic extension 2 of trapezoidal cross-section protruding on one side and at its downward-facing tip via an outlet opening 3 with a spherical extension q. of the container is in communication. The wider part of the extension 2, which protrudes laterally beyond the base of the container i, is separated at the bottom by a base with an outflow 5 and from the container i by an overflow 6. Opposite the overflow 6, a sieve plate 7 is installed in the narrow part of the extension 2, which does not extend to the bottom of the pyramid-shaped container i. Above the narrower part of the container delimited by the sieve plate 7 is a feed funnel 8 for the dry raw material in the first slurry body A, and in the slurry bodies B and C there is an inlet funnel g or io provided as a metering device with an overflow and outlet nozzle for the one from the previous one Sludge body provided for uplifted sediment. Another metering device of the same type is connected downstream of the slurry body C. In the pipes 12, 13 and 1q leading from the bottoms of the spherical extensions q., Hereinafter referred to as spheres, of the slurry bodies A, B and C to the metering devices g, io and ii, respectively. a pump 15 or 16 or 17 is installed, which feeds the sediment of each of the slurry bodies A, B and C to the respective downstream dosing devices 9 or io or ii.

Another pump 18 is connected to a pipeline i9 which is connected to the outlet 5 of the slurry body B and above the feed hopper 8 of the mud body A opens freely. The outlet 5 of the slurry body A brings that finished fines; that of the mud body C is through a pipe 2o with the Ball 4 of the slurry body A connected. The overflows 9a, ioa, 11a of the dosing devices 9, 1o and ii are connected to the ball 4 of the respectively by means of pipes 21 and 22 and 23, respectively previous slurry body connected.

Furthermore, the dosing of the total liquid supply is effective, from a line 24 continuously fed elevated tank 25 is provided with constantly flowing overflow 25a and drain 25b is equipped. In the bottom of the through the overflow 25a of the elevated tank kept at the same liquid level are two interchangeable Outlet nozzles 26, 27 provided certain passage cross-section from which pure Free jet of washing liquid through an air gap into a funnel-shaped each Compensation tank 28 or 29 flows out, of which the former by means of a pipeline 3o, the second by means of a pipe 31 each with the ball 4 of the slurry body B or C is connected.

After the system from the elevated tank 25 from flowing washing liquid has been fulfilled, the pumps 15 to 18 are put into action and that too treated raw material introduced dry into the feed hopper 8, wherein it with the from the overflow 6 and outlet 5 of the slurry body B by means of the pump 18 through the line i9 upwardly conveyed liquid gets mixed into the slurry body A. The fines are immediately captured by the stream of slurry, through sieve plates 7 entrained and pass through the overflow 6 and outlet 5 into the open. That still with Coarse material mixed with fine particles sinks in the pyramid-shaped container i and arrives through its bottom opening 3 into the ball 4, from which the sinkings through the pump 15 is conveyed via the line 12 into the inlet 9 and by means of nozzles and overflow in precisely dosed amounts into the slurry body B, where it is repeated Is subjected to the cutting process. The surplus of the raised debris flows back via the overflow 9a through the line 21 into the ball 4 of the slurry body A, into which, moreover, through the pipeline 2o from the overflow 6 and outlet 5 of the slurry body C originating liquid is introduced. The sinkage of the mud body B is from the ball 4 of the same by means of the pump 16 via the pipe 13 into the inlet io lifted, from which a metered amount of the sediment gets into the slurry body C, where the further divorce is going on while the excess of the enema io settled debris got through the overflow ioa and the line 22 into the ball 4 of the previous slurry body B flows back. The fine material of the slurry body C arrives, As already mentioned, through the line 2o into the ball ¢ of the slurry body A, while the sediment from the pump 17 via the pipeline 14 into the metering device ii is promoted, from where one iib through the passage cross section of the discharge nozzle the same certain amount of the sediment is discharged as finished coarse material while the excess over the overflow ija and the pipe 23 into the ball 4 of the last Slurry body C flows back.

The balls 4 of the slurry bodies B and C are via the tubes 3o and 31 with pure washing liquid from the elevated tank 25 with a certain dosage applied. From the material to be separated at 8 it becomes gradually progressive Separation process of the fines through the outlet 5 of the first slurry body A, the Coarse fraction at the nozzle i i b of the metering device downstream of the slurry body C. i1 applied.

The return of the overflow of the sediment lifted into the dosing devices 9, io and ii into the ball 4 of the respective preceding slurry body A or B or C, i.e. before the pumps 15, 16, 17, as well as the return of the fine material of the slurry body C. containing washing water in the ball 4 of the mud body A or the supply of pure washing water in dosed quantities from the expansion tanks 28, 29 in the ball 4 of each of the mud bodies B and C, contribute significantly to achieving high degrees of separation. The agglomerated sediment that has fallen through the opening 3 in the bottom of the container i of the slurry body is brought into a uniform suspension by the double liquid inlets described and by being whirled up in the pumps. The vortex movements caused in the balls 4 as a result of the two liquid inlets cannot get into the interior of the slurry body because of the considerable cross-sectional tapering of the ball 4 at its connection point to the container i. Through the specific setting of the inlets of the pure washing liquid or the fine portion of the next but one slurry body containing washing liquid in the balls 4 on the one hand and of the sink material portion fed from a slurry body to the respective following through the metering device of its inlet on the other hand, it can be achieved that in the bottom opening 3 of the respective slurry body in In the most favorable case, there is practically no liquid flow, which is necessary above all to achieve a high degree of selectivity.

The horizontal sludge system shown in Fig. 2 for liquid discharged material to be separated has four sludge bodies A, B, C and D in series, of which the first A has a larger sludge surface than each of the other sludge bodies B, C, taking into account the amount of carrier liquid of the grain suspension. D same slurry area.

In Fig. 2 all those of Fig. I corresponding parts with the same reference numerals as there are seen ver; the metering device added with the fourth slurry body D and the pipelines leading from this to the previous slurry body were given the designation of the corresponding parts in the third slurry body C, but with the index d, z. B. Dosing device rod. Instead of the pump of the embodiment of FIG. I, provided for scooping the suspended matter from the individual Schlämmkörpern A, B, C and D pneumatic fluid lifting devices 32, 33, 34 and 35, which are not represented by pipe connections 32a, 33a, 346 and 35a with a common air compressor are connected. Because of the entrained air, the pipelines 12 or 13 or 13, 1 or 4 that feed the sediment to the metering devices g, 1o, rod and 1i must have a larger passage cross-section. Otherwise, the line connections, as can be seen from the reference symbols and directional arrows, are the same as described with reference to FIG. 1 and thus also the mode of operation.

Fig. 3 shows the combination of two three-stage systems according to the scheme 2 for the sharp division of the abandoned at 8 in liquid suspension Raw goods. The finished fine material is at the outlet 51 of the first slurry body A1 first series connection A1, Bi and Cl discharged from the metering device Coarse material occurring in this system is fed into the feed hopper 82 of the first slurry body A2 of the second system A2, B2, C2 passed, from whose outlet 52 the finished medium is carried out; the finished coarse material is from the dosing device il, the second series connection obtained. i. Example Got to processing a quartz sand with predominantly rounded grains and with a sieve analysis like them is listed in section A below.

After a four-stage horizontal slurry in countercurrent under the conditions of this invention, a coarse material according to category B and a fine material according to category C were obtained. Sieve class ABC Rdhgut coarse fine material over 0.5 mm ...... 7.1o / 0 8.80 / 0 0 0% 0.5 to 0.4 mm ...... 20.50 / 0 25.5% 0% 0.4 - 0.3 mm ...... 27.2% 3390/0 0 0l0 From 0.3 to 0, 25 mm ...... 10.30 / 0 12.60 / 0 0.5010 0.25 - 0.2 mm ...... 7.1% 8.4% 1.5% 0.2 - 0.15 mm ...... 6.3% 64% 5.7% 0.15 - 0.12 mm ...... 4.2% 3.0% 93% 0.12 - o, og mm ...... 4.8% 1.2% 19.6% o, og - 0. o6 mm ...... 5.3% 0 # 2% 26.3% 0.06 - 0.04 mm ...... 2.2% 0 0/0 ri, 3% below 0.04 mm ...... 5.0010 0 0/0 25.8% Yields: parts 1 roo I 80.6 19.4 roo g of this raw sand are divided as follows Average percentage of the Sieve class Grain diameter raw material coarse material fine material fine material in this Sieve class over 015 mm ...... ? 7.19 7.1 9 and o0 / 0 0.5 to 0.4 mm ...... 0.45 mm 20.59 --0.59 0 g 0010 0.4 - 0.3 mm ...... 0.35 mm 27.2 g 27.2 gog o0 / 0 0.3 - 0.25 mm ...... 0.275 mm 10.39 10.2 go, / g r0 / 0 0.25 - o, a mm ...... o, 225 mm 7119 6.8 g 0.39 4% 0.2 - 0.15 mm ...... 0.175 mm 6.39 5.2 g 1.1 g i8 ° / ' 0.15 - 0.12 mm ...... o, 135 mm 4.2 g 2.4g i, 8 g 43% 0, i2 - o, og mm ...... 0.1o5 mm 4.8 gr, ° g 3.89 79% o, og - 0. o6 mm ...... 0.075 mm 5.39 0.2 g 5J9 96% 0. o6 - 0. o4 mm ...... 0.05 mm 2.2 gog 2.2 g 1 ° o0 / 0 below 0.04 mm ...... ? 5.0 gog 5, and 1 ° 0/0 100 g 1 8o, 6 g 1 19.49 The relationship between the second category and the sixth category in the table above is essential for assessing the selectivity. By interpolation one finds: from the sixth category from the second category 200/0 (separating grain size K20). . . . . . . . . . 0117 mm 5o0 / 0 (cutting size K50). . . . . . . . . .0, i3 mm 8o0 / 0 (cut size K80). . . . . . . . . . o, ro5 mm The grain spread x201 $, is K20: K80 = 0.17 mm: 0.105 mm = 1.6. z. Example A quartz sand with a predominantly rounded grain and the same sieve analysis as in example i was used for processing. After a four-stage horizontal slurry in countercurrent according to the above guidelines for the invention, setting a specific slurry flow of 1.5 cm / sec (0.15 l / sec / dm2 slurry surface), a separating grain size K50 of 0.1 mm was achieved. The grain spread xf! Oi8o of this separation was 1.5.

The coarse material from the above separation was again in a specific Slurry flow of 3 cm / sec, with a separating grain size K50 of 0.15 mm and a grain spread x20 / $ 0 for this second separation of 1.6.

3rd example A mixture of scheelite (specific weight 6) and a silicate with a specific weight of 2.6 was used for processing. In this raw material ioo g were included: Scheelite I silicate over 0.2 mm ....... 39 above 0.2 to o, i mm ....... 28 g 159 o, i - o, o6 mm ....... io g 309 below 0.06 mm ....... 49 log 459 559 After a four-stage horizontal countercurrent slurry according to the conditions of this invention and at a specific slurry flow rate of 4 cm / sec, two fractions with the following composition and sieve analyzes were obtained Raw material: roo g Fine material Coarse material 62 g 38 g Scheelite Silicate Scheelite Silicate over 0.2mm. . . . . . . . . . . og 0 g 39 og o, i to o, 2 mm. . . . . . . . . . . 2 g 139 26 g 2 g o, o6 - o, i mm. . . . . . . . . . . 49 309 6 g 0 g below 0.06 mm. . . . . . . . . . . 39 10 g 1 go g 99 53g 36g 2g While the raw material had a scheelite content of 45%, this was increased to 95% in the coarse material. The waste product (fine material) still had a scheelite content of 15%. A total of 20% of the original scheelite went into the fine material.

Claims (5)

PATENT CLAIMS: i. Continuous horizontal slurry process with at least two successive stages, each of which emits fine material and sediment, characterized in that the sediment suspended in liquid is conveyed up at least one level, a constant flow of the raised sediment suspension is directed into the inlet of the next step, the overflowing flow into the from the previous, e.g. B. first stage (A) drained sediment and in this sink before its entry into the conveyor (15 or 32) either pure or the fine material of the next but one stage (C) containing washing liquid is introduced, according to the setting of the inflow quantities of this Washing liquid and from a, z. B. the first stage (A), the inlet (9) of the next stage (B) fed sink material suspension at the outlet opening (3) for the sink material at least one stage a liquid flow in an ascending direction of at most 200/0, in a descending direction of at most 15% of the total slurry flow is allowed. 2. Horizontal slurry process according to claim i, characterized characterized in that the above-mentioned feed rates receive an adjustment, according to which at the outlet opening (3) for the sediment at least one stage the flow velocity practically becomes zero. 3. Horizontalschlämrnverfahren according to claim i or 2, characterized in that the specific, ie the slurry flow based on the unit of the mud surface in all successive stages (A to C or A to D) is kept practically the same, at most in each subsequent stage selected to be smaller will. 4. Horizontal slurry process according to one of the claims i to 3 for the precise division of the goods into at least three sludge classes, characterized in that at least two series connections (Al, B1, Cl and AE, B2, C2) are combined by slurry levels, starting from the first Series connection (Al, B1, Cl), which has the smallest specific slurry flow identifies all subsequent series connections with always increasing specific Mud flows work and that the accruing in each series connection Fine fractions deducted as finished products, but including the coarse fractions the penultimate must each be brought to a new elutriation (Fig. 3). 5. Plant for performing the method according to one of claims i to 4, characterized in that below the bottom opening (3) at least one slurry body of a series connection of such (A, B, C) an approximately spherical vessel (4) open at the top is attached whose upper taper z. B. is the same as the passage cross-section of said bottom opening and that at least one slurry body (B) is assigned a device (9) with an outlet nozzle and a certain passage cross-section and overflow (9a), which dosing from the previous slurry body (A) into the inlet of the lower high-conveyed sediment, two pipes (21 and 2o) opening into the above-mentioned spherical vessel (4), one of which (21) is the overflow of the sink material metering (9) of the following slurry body, the other (2o) or with the fine material of the next but one slurry body (C) loaded pure washing liquid supplies (Fig. i and 4).