Slurry mixer
A slurry mixer , slurry mixer or Slurry is a device that especially in agriculture but also in biogas - and sewage treatment plants for stirring slurry is used and similar mixtures.
Slurry is a regularly arising in livestock liquid manure , which prior to targeted application to arable - or grasslands must be stored. They are mostly stored in open or closed manure silos . Settling processes can lead to clumped floating and sinking layers, which impair the pumping and flowability of the slurry and prevent the storage facility from being completely emptied. The separated layers of manure can be mixed with a slurry mixer, which again creates a flowable mass with homogeneous nutrient distribution. This is for trouble-free pumping processes ( slurry pump, slurry tanker) and important for even fertilizer application.
Structure and shapes
Depending on the intended use and manufacturer, slurry mixers are offered in various designs and sizes. The devices basically consist of a drive unit, a more or less long metal rod ("stirring rod", "mixer pipe" with integrated shaft and / or holding device) and a mixing unit ( propeller , stirring blade, paddle blade). There are mobile and stationary mounted slurry mixers.
Drive types
After the drive way, let PTO driven attachments Mixer (also tractor blender or PTO Mixer called) of directly to a motor connected or even equipped with a motor engine mixers differ. Slurry mixers operated with an electric motor are generally referred to as electric mixers, regardless of their design . These are advisable in mixed residential and agricultural areas of the villages, as they considerably reduce the noise emission that lasts for hours. The harmful emissions such as soot and incomplete combustion products that occur with tractors operated with diesel fuel can then be avoided.
In tractors, it is usually attached to the three-point hydraulic system , but it can also be attached to the front loader of tractors as well as to telescopic loaders or wheel loaders . Mobile mixers can be equipped with stands or chassis that only require connection to a PTO shaft using a cardan shaft or to a motor.
Linkage and designs
The mixer rod can be made in one piece, rigid (hand blender ) or in several parts, pivotable and foldable with the help of swivel joints . Particularly long slurry mixers can be provided with supporting frame structures to stabilize the boom . Rigid slurry mixers are particularly suitable for use in closed or open deep silos ( slurry pits , slurry lagoons) and - then also known as sewer mixers - in slurry channels built under the barn (exchange system, slalom or ring channel circulation). Multi-unit Güllemixer come as Folding PTO or tower mixer at low Rangiermöglichkeiten and especially in elevated tanks are used. There are also multi-link, trailer-mounted and self-propelled slurry mixers that resemble concrete pumps with their large hydraulic booms . They are mainly used by contractors .
Portable or stationary submersible mixers are similar to the usual stick or swivel mixers , but have a rotatable underwater motor positioned directly on the propeller, which is also immersed in the slurry and must therefore be specially protected. They are usually equipped with planetary gears and, due to their slim design, have favorable fluidic properties. An extension of the submersible mixers is the function of the stirring tunnel. Here a submersible mixer is installed directly as a kind of height-adjustable wall in the slurry cellar. The wall is sealed with a film so that the slurry in the slurry channel or slalom system is only stirred by the submersible mixer, without the substrate flowing back.
Axial agitators can be driven in different ways , mostly electrically via a planetary gear. They do not have a propeller, but rather several large, horizontally rotating blades on a vertical rod that is permanently installed between the floor and ceiling of a closed slurry store. The wings are usually arranged in pairs. A pair of wings, rigidly mounted near the ground, stirs up sinking layers at the bottom, and another pair of wings, which is suspended in a floating manner and thus adapts to the slurry level, stirs up existing floating covers. Axial agitators are particularly suitable for larger or misshapen slurry stores, for example for long slurry pits with a partition.
A special type of slurry mixer are small column mixers or column mixers , which are mostly driven by integrated electric motors. These mobile devices can - even without moving the animals - be used in cattle stalls that are equipped with slatted floors and a slurry store underneath. Thanks to a chassis that is a four-wheeled transport cart for some manufacturers and a hand truck for others , they can be easily moved by one person. A drive unit (e.g. an electric motor) and a mixer sword (flat mixer rod) and a folding propeller or, more rarely, simple stirring blades are mounted on the chassis. The mixer sword is oriented vertically downwards by default and can be lowered through a gap in the floor, which is often done mechanically using a crank and cable winch . Ideally, the sword can still be swiveled in the direction of the column. The folding propellers or blades can be inserted and removed through the slits parallel to the sword. According to the different slatted floor dimensions, we also speak of beef slat mixers and pork slat mixers . Normally, column mixers do not replace larger slurry mixers, but are used in addition and especially in problem areas with intensive liquid manure consolidation or for targeted fly brood control in stables. House flies in particular often lay their eggs in layers of liquid manure. Among other things, the droppings and feeding points of the animals under slatted floors are problematic, as there are increased solids content. To improve the agitation process with dry manure or thick layers and for floating storage of the agitator blades, column mixers can also be equipped with a water supply to the propeller.
Propellers and accessories
Propellers for slurry mixers are available in both pushing and pulling / sucking form. In addition, models with suitable propeller blade shapes are produced, in which you can switch between forward and reverse rotation. Depending on the dimensions of the slurry storage facility, different propellers are used so that all areas are captured and stirred up. In general, floating layers can be dissolved better by pressing, sinking layers more by pulling. In angular manure stores, propellers are often used to pull the manure towards the mixer and thus prevent the solid matter from building up on the opposite side. In round liquid manure tanks and in sewer systems, propellers are usually used, which stir up the floating layer by pushing it away and allow it to circulate.
Sometimes it is necessary to add oxygen to the manure . For this purpose, slurry mixers can be equipped with additional ventilation units (air intake, pressure hose, aerator head on the propeller). The same applies to an optional water supply device for diluting the manure during mixing. Likewise, cutting units can be attached which, parallel to stirring, chop up leftover feed or straw introduced to reduce emissions . Protective baskets, protective boxes, protective rings, simple frames or stands can also prevent damage to the propeller during use or storage.
Individual evidence
- ↑ a b c d e f Eduard Zentner: Which slurry mixer is right for my company. (No longer available online.) In: Top Agrar Journal (Austria) 10/2004. Higher Federal Education and Research Institute Raumberg-Gumpenstein , formerly in the original ; accessed on July 8, 2010 (PDF, 121 KB). ( Page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
- ↑ a b Slurry technology, agitators. A. Wälchli Maschinenfabrik, accessed on July 10, 2010 (manufacturer's website).
- ↑ a b column mixer. Reck Agrartechnik, accessed on July 10, 2010 (manufacturer's website).
- ↑ Sewer mixers. (No longer available online.) Vakutec slurry technology, archived from the original on March 4, 2016 ; accessed on July 10, 2010 (manufacturer's website). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
