DE2629132C2 - Device for the continuous clarification of sugar juices - Google Patents

Description

a) an annular one consisting of several tubes (11) Channel (30) for charging the container (15) following the supply line (8),

b) scrapers (14) which are hinged,

c) a rectangular connecting shaft between the compartments (12) in the axis of the cylindrical container (15) and between baffles (19) runs along the bottoms (3), as well

d) a thickening plate (2) in the lowest compartment of the container (15).

2. Device according to claim 1, characterized in that the cross section of the rectangular connecting shaft (12) increases in the direction from the channel (30) to the lowermost floor (3).

3. Device according to claim 1 or 2, characterized in that the channel (30) has a gas discharge line (4).

4. Device according to one of the preceding claims, characterized in that the floors (3) are arranged at the same intervals, but the distance of the sub-floor (16) from the overlying Floor (3) is greater than the distance between two adjacent floors (3).

5. Device according to one of the preceding claims, characterized in that the thickening plate (2) is flat, one diameter from 50 to 60% of the diameter of the container (15) and a distance from the bottom (16) of is at least 460 mm.

6. Device according to one of the preceding claims, characterized in that the sub-floor (16) has a cone angle between 10 and 20 °.

7. Device according to one of the preceding claims, characterized in that the length of the Pipes (11) of the channel (30), the distance between the lower ends of the pipes (11) and the ground (3) of the top compartment and the height of the deflector plates (19) are dimensioned so that when loading of the container (15) with sugar juice this meets a sugar juice with the same density.

8. Device according to one of the preceding claims, characterized in that the channel (30) has an intermediate wall (7) arranged therein with vertical slots and a deflection ring (10) is provided at the lower end of the tubes (11).

9. Device according to one of the preceding claims, characterized in that two leads (8) are provided, which are clockwise tangential to the channel (30) and opposite one another arranged and the outlet openings are each provided with a guide plate (18).

10. Device according to claim 8, characterized in that the channel (30) with tubes (11) is equipped, the same distances and the same diameter, and that a scraper (9) for Cleaning of the deflector ring (10) is provided.

11. Device according to one of the preceding claims, characterized in that for the removal of clear juice on the circumference of the bottoms (3) there are four Arc-shaped arms (21,22) with a plurality of drainage openings (28) are provided which are connected to a collecting line (25) are connected, the connection of the drainage openings (28) to a collecting container (24) from common pipes arranged at equal distances from one another

(26), which is arranged above the collecting container (24) are.

• 12. Device according to one of the preceding claims, characterized in that in the uppermost Compartment two gutters (5) are provided through which

Upper course clear juice can be absorbed, whereby one overflow channel (5) inside and the other overflow channel (5) outside the channel (30) are located.

13. Device according to one of the preceding claims, characterized in that over the base (3), the thickening plate (2) and the sub-base (16) scrapers (14) each having the same length and different heights are provided, the Scraper (14) over the lowest floor (3), the thickening plate (2) and the sub-floor (16) the largest Have a height that corresponds to 1.5 times the length of the smallest scraper (14).

14. Device according to claim 13, characterized in that the scraper (14) on rotating arms are attached, which in pairs form an angle of 180 °, the associated scraper (14) in a certain angular inclination with respect to the pivot arms after facing away from their direction of rotation Side are angled.

15. Device according to one of the preceding claims, characterized in that the scraper (14) are concave in their upper part (20) with a certain angle of inclination and at their have a replaceable scraper bar at the bottom.

16. The device according to claim 14, characterized in that the arranged on the rotating arms Scraper (14) on the top floor (3) offset from one another, but on the lowest floor (3), on the sub-base (16) and on the thickening plate (2) arranged in consecutive order are.

The invention relates to a device for the continuous removal of suspended matter, which in It contains sugar juices made from sugar cane. This is the case when clarifying cane sugar juices Main goal in the production of clear and light juices, which are free of insoluble substances, as well as of viscous molasses foams with a high proportion of solids for better desugarization during filtration.

A continuously working clarifier for cane sugar juices basically serves two processes, namely free sedimentation and thickening

by mechanical compression. The former is mainly done depending on the properties of the raw material used, on the efficiency of the alkalization as well as the technological parameters of the clarification facility. The latter are different from the free sedimentation is determined by the design of the facility, although it is an unavoidable requirement is that the free sedimentation takes place without impairment

Various continuously operating clarifiers are currently known for sugar juices that are delivered to a Aim to shorten the dwell time. Underneath are the multi-cell clarifiers, which are ring-shaped and fed radially, the clarifying cells being conical and by means of concentric rings in the Are distributed inside the facility. The main disadvantage of this type of construction is that this Cone clogs when the amount of solids that settle is large also makes it difficult Construction form of the cones their cleaning.

Another known design with a short residence time is a clarifier with a single sedimentation chamber or flat tub, which is fed in a ring and centrally. This is where the main disadvantage lies in that in the event of a turbulence of the settling solids, because of the flat bottom, all of it Facility is affected by this whirling and therefore the loading must be stopped. aside from that In this design, the short residence time is mainly due to the use of flake-forming Substances.

There are also facilities with several horizontal or something for the continuous clarification of sugar inclined flat floors, on which there are scrapers for compacting the molasses foam. A so-called flocculation chamber is provided in which the alkalized sugar juice flows and from there passes through the various sedimentation floors or compartments. Feeding the flat Flooring can be done from the circumference or from the center, depending on the type of construction.

From GB-PS 8 37 595 is a clarifier with a cylindrical container, several floors over the Scraper are guided, a sugar juice feed in the top container compartment, a discharge of clear juice on the outer periphery of the compartments, a discharge of the sediment in the middle of the container, a lower thickening plate and a gas discharge known for each compartment.

In DE-AS 13 00 082 a device for alluvial clarification of sugar pulps is described. the Sugar liquids to be clarified are fed in below the liquid level.

DE-OS 14 17 642 reports on a clarifier with different floors, whereby the opening cross-section for the supply of the liquid to be clarified increases from floor to floor. The liquid is fed into each compartment in the peripheral area.

The known devices have the following major disadvantages:

They have a long residence time, which results in losses due to the inversion of sucrose; the scraper are too weak and therefore do not achieve perfect compaction of the sediment; the performance of this Facilities is hampered by the fact that they only have a small area for peeling off the thin or Show clear juice; the charging does not take place where the density of the sugar juice and the degree of saturation corresponding to each other, causing cloudiness and / or turbulence in the juice; in In some cases the flat bottoms have openings that are too large so that the area for compaction of the sediment is small

The invention is based on the object of a device specify for the continuous clarification of sugar juices, which with small dimensions a short Residence time and good compaction of the sediment

ίο guaranteed, while at the same time the use of flocculants is superfluous and the formation of cloudiness in the clear juice and clogging of parts of the device by sediment are prevented.
This object is achieved by the invention by a device with a cylindrical container which is divided into several compartments by several conical bottoms with scrapers above and a sub-floor, at least one supply line in the uppermost compartment for the sugar juice to be clarified, outlets for clear juice on the outer circumference of the bottoms and discharges for gases from each compartment.
The facility is characterized by

a) an annular channel consisting of several tubes for charging the container then to the supply line,

b) scrapers that are articulated,

c) a rectangular connecting shaft provided between the compartments, which is located in the axis of the cylindrical container and between baffles on the bottoms, as well

d) a thickening plate in the bottom compartment of the container.

In the device according to the invention, the sugar juice is supplied at the points where the density of the juice in the facility is about as large as that of the incoming sugar juice. This is made possible on the one hand by the length of the pipes of the channel for the loading of the container and the distance between the lower ends of these pipes and the bottom of the topmost compartment and on the other hand through the Height of the baffles on the floors. This achieves a laminar juice form. The individual compartments and floors are connected to each other in the middle by a rectangular connecting shaft Dimensions favor hydrodynamics in the supply of the sugar juice and the outflow of the molasses foam. In addition, this connection shaft allows the flat floors such an incline and To give shape so that three different zones are formed in each soil: A first zone for the Clear juice, a second zone for the medium or medium-clear juice and a third zone for the molasses foam. The optimal removal and loading height can be set, with a perfect distribution of the fed-in juice and a steady flow of substances in the facility.

The facility's performance is fully utilized, because the respective withdrawals individually via the floors, the gas discharges, which in the possibly existing so-called dead zones are attached, as well as via the top compartment of the facility. the In contrast to the usual devices, the device according to the invention does not have a flocculation chamber because the tubes of the annular channel due to their length, Their diameter and number determine the reaction between calcium hydroxide and phosphate in the Allow inside the tubes. Compared to other

gen sewage treatment plants with annular channels for the juice supply, the device according to the invention has a larger contact area for the completion of the reaction. The scrapers used here are robustly built, have depending on the diameter of the cylindrisehen container and the clearance between the individual floors larger than usual. The scrapers have one on their lower part Scraper bar made of soft or elastic material.

The scrapers are concave in their upper part with a certain angle of inclination, what the Taking along, compressing and removing the molasses foam on the floors and the sub-floor of the Facility favorably influenced. The thickening plate in the bottom compartment improves the thickening of the molasses foam and regulates its movement towards the perimeter of the subfloor, thereby increasing the volume of the molasses foam is decreased.

Because of all of the above features it results in continuous, high speed clarification of sugar juices taking place in a facility whose dimensions are 60 to 70 ° smaller than in common facilities and in which sugar juices with a high sediment content of 5 to 8 percent by volume can be processed with a residence time that is 75% lower than the usual residence time, i.e. H. at about an hour. In this way, perfectly clarified sugar juices are obtained without the addition of coagulants or other auxiliary materials.

In addition, the device according to the invention offers improved possibilities for automatic control of the procedure.

An exemplary embodiment of the invention is shown schematically in the drawing. It shows

F i g. 1 shows a cross section through an embodiment of the device;

F i g. 2 is a perspective view of the annular, multi-pipe duct for loading the facility;

Figure 3 is a perspective view of the deflector at the connection shaft;

F i g. 4 shows a longitudinal section through an angled scraper;

F i g. Figure 5 is a top plan view of the annular, multi-tube channel; and

F i g. 6 is a plan of the device with its derivatives.

A cylindrical container 15, the height of which corresponds approximately to its diameter, has a conical shape Sub-floor 16 with a cone angle between 10 and 20 °. Inside the container 15 there are several flat, only slightly inclined bottom 3. These are arranged in such a way that they individual Form compartments that are connected to one another at the same distance apart, with the exception of the lowest Compartment whose distance from the compartment above is greater than the distance between the rest Compartments is dimensioned In this lowest compartment there is a concentric to the wall of the container 15 Thickening plate 2, which is flat and one Diameter of 50 to 60% of the diameter of the device and a distance from the sub-floor 16 of is not less than 460 mm

The equipment is fed via an annular channel made up of several pipes 30, which has in its interior a partition 7 with vertical slots through which the Distribution of the fed-in sugar juice takes place through the upper course and its rectangular shape and opening and closing cross-sections are chosen so that blockage by solid impurities in the sugar juice is prevented. In addition, a gas discharge line 4 is provided for the extraction of the gases that occur during Overflow. The stream of alkalized sugar juice is tangential to the annular channel 30 over two feed lines 8 introduced, the outlet openings of which are arranged diametrically and each with a guide plate 18 are provided that prevent vortex formation during the distribution of the juice. At the bottom of the tubes 11 is arranged for the distribution of the sugar juice in the first compartment, a wide deflection ring 10, which by means of a articulated scraper 9 is kept clean. From this first compartment it is possible to pass through Overflow in channels 5 clear juice to be found.

The supply to the numerous flat floors 3 takes place through the middle rectangular connection shaft 12, from the top to the bottom floor leads and thereby increases its cross-sectional area to an increasing extent. The connection shaft 12 is formed with the help of baffles 19. The solids that settle on each of the floors 3, are carried along in the direction of the connecting shaft 12 by scrapers 14, which are also used for compaction contribute to the solids and also on the sub-floor 16 of the device and on the thickening plate 2 are present. These scrapers 14, which are robust and have large dimensions, are articulated attached and have on their upper part 20 a certain concave bend, which the entrainment and condensation of the molasses foam. The scrapers are on arms offset by 180 ° mounted and are thus moved in opposite directions in plan view; they are on the top floor arranged offset, but on the lower floors, on the thickening plate and on the sub-floor 16 in consecutive order attached ·.

The clear juice is removed from the circumference of each base by means of circular arc-shaped arms 21, 22, which have a plurality of drain openings 28 which are arranged at equal distances from one another and the dimensions of which are different according to those of the bottom 3. To the collecting bins 24 lead from each base from individual pipelines 29 and a common pipeline 26, each at a collecting line 25 is connected and through which the clear juice rises from the floors, with the exception of the last soil, the clear juice of which has already been absorbed by the arcuate arms 21, 22. The individual pipelines 29, which start from the top floor, are in front of the confluence with the Provide the manifold with a valve so that the flow rate can be regulated.

The discharges 23 for the gases from the floors are arranged symmetrically to one another, while the discharge of the sub-floor 16 is attached by itself The drains can be used to clear juice; can be taken from the so-called dead zones.

Furthermore, a derivation 6 from the further outside located overflow channel 5 for the clear juice, an auxiliary line 13 for liquefaction and cleaning, an inner wall 17 of the channel 30 and a quick release slide 27 provided.

For this purpose 2 sheets of drawings

Claims (1)

Patent claims: 1. Device for the continuous clarification of sugar juices with a cylindrical container (15), by several conical bottoms (3) with overlying Scraper (14) is divided into several compartments and a sub-floor (16), at least a feed line (8) in the uppermost compartment for the sugar juice to be clarified, outlets (29) for clear juice each on the outer circumference of the floors (3) and down conductors (23) for gases from each compartment, characterized in that provided are