Process and device for separating solids from mud with screw presses.

The invention relates to a process for separating solids from liquids slimy with separators, in which the pressing pressure is built up by means of a screw; It further relates to a device for carrying out the process with separators, in which the pressing pressure with the aid of a screw is constructed with a housing, in which at least one strainer basket and one screw are disposed and which at least comprises a filling chamber as well as a solid and a liquid discharge ,

The use of Flüssigentmistung has been proven in animal intensive farming and is applied to an increasing extent. This development techniques have been developed to separate when Flüssigentmistung manure produced in the components "solid" and "liquid phase". In a report from the Institute of Technology of the Federal Agricultural Research Centre, Braunschweig-Völkenrode, published in Grundl. Agricultural Engineering Vol.<u>37</u> (1987) no. 3 pages 98/107, the problem areas of Flüssigentmistung and the importance of the solid-liquid separation of the slurry were of R. Krause and R Ahlers entitled "Process Engineering of separating liquid manure" shown. Furthermore, the advantages and disadvantages of individual devices were identified and compared. This publication has been the basis of the representation of the characteristic of the known technical solutions and the critical analysis of the European patent application with the application number 89 119 460.7 "process for dewatering water-suspended solids and screw extractor for it."

The "Time Series of Building Consultancy cement" the publisher CONCRETE, published in the brochure "manure" 1988, page 102/106 the Prizipien of separating. Here a Strainer is described, for example, the screw is guided over a stationary strainer basket, while the European Patent Application 0062628 A1 also describes a Strainer whose screen drum with the internal screw rotates with.

In practical operation, however, showed that the necessary for composting value for the dry matter content in the solid of more than 30% was achieved only by the decanters and the press screw newer design of certain types of manure. Especially when deposited bovine Guellen at Guellen derived from animal systems with a summer grass feeding and similarly intractable slimy suspensions these machines did not yield satisfactory results. In the decanters the mucilage prevented sufficient drainage despite high centrifugal forces. In Preßschneckenseparatoren it comes at a correspondingly high viscosity not necessary gravity drainage through the openings of the screen basket so that the slimy mixture is not detected and the press portion can be further dewatered.

From the field of concrete compaction have long been known vibration devices that alter the viscosity behavior of the material to be processed. This is also the objective patent publication DE 34 26 737 A1, in the vibration devices in settling tanks or containers for the change in viscosity and are therefore used to facilitate sedimentation of the solids.

Hence the the problem underlying the invention, which is seen to further develop the known method so that the indicated problems are avoided and to Guellen drain with high mucilage content and thus high viscosities by simple means so that the residual moisture content of the separated solid allowing further use eg for composting to develop this for screw presses and Preßschneckenseparatoren previously uncontrolled area of ​​application for these devices; it is also part of the task to develop the device so that the process can be carried out with the use of under the conditions of a farm operation simple and robust devices.

This object is achieved for the method by the features recited in the characterizing part of claim 1; the solution of the device part of the task to give the characteristics listed in the characterizing portion of claim 2, wherein an advantageous development is described by the dependent claim.

Since it is "non-Newtonian" fluids in the present solid-liquid mixtures, vibrations are introduced into the filling chamber of Preßschneckenseparators whose effect continues up to the entrance area of ​​the screen basket, thereby reducing the viscosity of the slimy liquid causes, thus enabling the required for the separation of the solids gravity drainage. This is due to the fact that the viscosity of such "non-Newtonian" fluids in a highly agitated state is lower than in the less or non-moving state. This continued into the strainer into vibration, the viscosity is reduced in this critical area, thus creating the conditions for a effective-will of the screen. The viscosity of the slimy liquid is lowered so much that it can flow through the openings of the screen basket. This takes place as long as a concentration of the solid until the worm can capture solids and build a press pressure, which leads to a further separation of the slimy liquid from the solids and thus its further dehydration.

The apparatus for performing the method is formed so that the vibrations generated by an out-of Befüllraumes vibrator are transmitted via support ribs on a present in the liquid oscillator, in which a membrane ensuring the closure of the inner space and supported all oscillating elements of springs or rubber buffers be and move accordingly in the vertical direction in the vertical. It consists of a vibrator and a device for the entry of the oscillations in the liquid. An oscillatable membrane separates the external vibrator from the inner space, thus preventing leakage of liquid to be treated. The oscillation is advantageously oriented such that the preferred direction of oscillation is the vertical.

In order to produce vertically directed vibrations vibrators having a directional or non-directional vibration can be used. When using vibrators with undirected vibration corresponding stabilizers are arranged as a link, which takes place the entry of the oscillations in the vertical direction, wherein the stabilizers lead on the one hand, the vibration device and are connected to the fulcrum side to the case of Preßschneckenseparators.

The essence of the invention is explained in greater detail on the execution Beipiels shown in Figure 1; this shows the<dl id="dl0001"><dt>Fig. 1:</dt><dd>A schematic view of a Preßschneckenseparators with vibration device;</dd><dt>Fig. 2:</dt><dd>Detail of the vibrator.</dd></dl>

From the stable area, the slimy slurry 1 is pumped into the filling chamber 2 a Preßschneckenseparators with a pump. On the lid 3, a vibrator 4 is arranged, which can transmit the vibration to the vibrator 6 via the support ribs fifth The membrane 7 is clamped between the connecting plates 8, thus closing the separator interior to the outer vibrator out and allows the free movement thereof. advantageously be employed simple powerful vibrators that emit omnidirectional vibrations. For the introduction of vertical vibration in the slimy liquid 4 stabilizers 10 are arranged on the mounting plate 9 of the vibrator, which are designed as handlebars. These cause the vibrator to one side and are connected to the fulcrum side to the case of the separator. All vibrating elements are supported by resilient members such as rubber buffers or springs 11th

2 shows the vibration device is shown enlarged. The vibrator 4 is seated on a mounting plate 9 which is in turn connected with the stabilizers 10th The stabilizers 10 are here represented by a compound 10.1 as a linkage, supported on the housing of the separator, which is covered in the region of the inlet for the slurry 1 having a lid third This lid 3 has an opening which is closed by a membrane 7 which is in turn provided with a circumferential frame 3.1, for clamping said membrane 7. The vibrator 4 acts on a clamp 5 on the membrane on the vibrator 6, the radius the screw correspondingly adapted half-shell, the vibrations transferred to the slurry in the inlet chamber of the separator. The stabilizer 10 is dargestellt- supported by resilient elements -here as springs 11 against the separator housing. It goes without saying that the stabilizer can also be designed symmetrically with its elastic support; in this case these are provided on both sides of the vibrator 4th

The introduced vibration improves the flowability of the slimy liquid, so that it can flow through the gap advantageously shaped openings of the screen basket 12th By related concentration detected driven by the gearmotor 13 screw 14, the solids and pushes it to further dewatering in the pressing region 15 of the separator.

The output controller 16 affects the required strength of Feststoffpfropfens. While the separated solid 17 now falls as krümliges product, the sieved liquid 18 flows through the pipe 19 from out of the machine.