DE3609638A1 - Method for the filtration of a poorly-filtrable beer-yeast mixture - Google Patents

Abstract

A method for the filtration of a poorly-filtrable beer-yeast mixture, in particular from a brewery. The filtration is carried out in a filter press having filter chambers, separated from each other by filter cloths, arranged one above the other or one after the other or having membrane filter chambers in a filter frame. At the start of the filtration, a primary layer of yeast is precoated onto the filter cloths. In the subsequent filtration, a beer-yeast mixture, of fermentation tank yeast and sediment yeast in different proportions and different qualities, is filtered.

Description

The invention relates to a method for filtration of beer-yeast mixture difficult to filter, in particular from the brewery, in a filter press Filter cloths separated from each other or one above the other filter chambers or membrane arranged one behind the other filter chambers in a filter frame.

In a brewery, beer is a by-product producing two different types of yeast Fermentation cellar yeast and the lees yeast. Both yeasts are more or less mixed with beer and accordingly thin.

The beer loss, the so-called Schwand, at the Bierher Keeping the position as low as possible has been around for a while a long time also the beer from the fermentation cellar yeast and the lees, especially by filtering them recover liquid yeast.  

It is also known in the art that mostly yeast beer beer mix easily from the fermentation cellar by filtration let separate. The separation, however, is more difficult of the leek in lees and beer.

For this reason, both yeasts are mixed so far and filtered as a mixture, especially at least some measured the disadvantages in terms of filterability of the girder to compensate. The success is low, because the filter cloths clog very quickly and un become permeable.

Several imponderables are for the more difficult fil portability of the girder is decisive. It is announced take that protein, dead yeast cells and that from the cell contents leaked from the dead yeast cells essentially responsible for the difficult filtration are literal.

All of these substances, hereinafter be called yeast ingredients is more or less amorphous and forms one greasy, slimy mass covering the drainage paths in the Filter cloths and in those of healthy yeast cells Lay or block the bridges in the filter cake.

It would be possible with the support of filter aids agents, especially diatomaceous earth, perlite, cellulose etc. to open a liquid-permeable filter cake to build. However, this is not possible for various reasons Lich, mainly because the yeast doesn't afterwards is more pure, but interspersed with foreign substances. Among other things, it is e.g. for veterinary reasons not allowed, enriched with diatomaceous earth or perlite Feed yeast to animals.  

Accordingly, it is the object of the present Invention, a method of filtering heavy to improve the filterable beer-yeast mixture in such a way that without the use of a filter aid such as Diatomaceous earth, perlite etc., with optimal use of the Filter capacity an increase in the amount to be filtered Beer-yeast mixture per filtration cycle or per Unit of time and / or an increase in dry matter content of the yeast cake is reached.

According to the invention, this object is achieved by that a primary layer of yeast at the beginning of the filtration the filter cloth is washed up and that at subsequent filtration from a beer-yeast mixture Fermentation cellar yeast and gelager in different parts len and different qualities is filtered.

The primary layer that begins at the start of filtration the filter cloth is washed up, forms one Protective layer and prevents the greasy, slimy yeast ingredients from the jelly itself in the free passageways of the filter cloths nest, lay them and ultimately the filter door Make it completely impermeable to liquids.

The primary layer, that of an approximately even one Thickness over the entire area of each filter cloth has a thickness of 1-5 mm, which makes the guarantee is given that from the following Filtration of the beer-yeast mixture from fermentation cellar yeast  and Gelager entrained yeast ingredients in the channel system of bridges of the primary layer who the and not at all to the film behind it can get cloth.

According to the invention, the primary layer is formed use liquid fermentation cellar yeast enriched with beer det.

Surprisingly, it has been found that one Pri washed up from fermentation cellar yeast optimal filtration and retention properties against the following, from the Geläger draining yeast ingredients.

The decisive advantage of the invention is that The fact that the primary layer consists exclusively of Fermentation cellar yeast is formed.

Fermentation cellar yeast has only a few yeast ingredients. The strong and healthy yeast cells form liquid permeable bridges through which the liquid, the Beer that can expire. In the bridges Channels become the yeast ingredients at the same time retained from the railing without these channels we to clog considerably.

The primary layer can advantageously at least washed up with the filtration rate.  This ensures that the primary layer in the essentially relatively evenly throughout Surface of each filter cloth is washed up. It can depending on the viscosity of the fermentation cellar yeast beer mixture with correspondingly different Precoat speeds can be worked. Fermentation cellar yeast has a dry matter content between 4 and 12%.

In an embodiment of the invention, the railing can liquid fermentation cellar yeast enriched with beer zudo be settled. This has the decisive advantage that no mixing tank is necessary in which the individual Settling types of yeast more or less in layers and so the required homogeneous mixing is not guaranteed animals. The fermentation cellar yeast in the yeast mixture has loosened up de function to the filter cake for subsequent Keep batches permeable to liquids.

By continuously "pressing" the rack to the beer-yeast mixture from the fermentation cellar in the feeder line to the filter press becomes a uniform one and thorough mixing of both types of yeast guaranteed.

The application of the inventive method for Filtration of difficult to filter yeast is used a basic sketch explained.  

At the beginning of the filtration, a mixture of fermentation cellar yeast and beer is fed to a pump 2 via line 1 and introduced through line 4 into a filter press (not shown) and thus a primary layer is applied to the filter cloths (not shown). At the same time, the gas in the filter press is pushed out of the filter press. As a precoat amount, the simple volume in a filter press is sufficient. A flow meter 3 is installed in line 4 . The precoating speed is in any case not less than the filtration speed; Preferably, however, gear is processed at such a precoat speed, which corresponds to approximately twice the filtration speed. The decisive factor for the precoat speed is the consistency of the beer-yeast mixture. Usually this can be 4% -12% dry matter content in a fermentation cellar-yeast mixture. Accordingly, you will work with a thin mixture with slightly higher precoat than when the mixture is thicker. Experience has shown that the floating of the primary layer is complete after a few minutes, preferably 2 minutes. For an optimal primary layer, such a precoat has been found to be sufficient, which corresponds approximately to the simple volume of the filter press. The thickness of the primary layer is then approximately 1-2 mm evenly on each filter cloth.

Gelager is fed to a further pump 6 via a line 5 . From this pump 6 , the bearing is pumped into line 4 via a connecting line 7 . The confluence of line 7 and line 4 advantageously takes place between the outlet of pump 2 and flow meter 3 . A quantity-proportional control is regulated via a control circuit 8 , which is connected between the flow meter 3 and the pump 6 . It can be used to precisely define the mixing ratio of fermentation cellar yeast beer mixture to gelager. The pressure control is regulated via the pump 2 and a control (not shown) connected to this.

After introducing the fermentation cellar yeast-beer mixture into the filter press, the pump 6 is switched on and gelier is added to the fermentation cellar yeast-beer mixture in line 4 . At the same time, the output of pump 2 is throttled. All of these processes can be regulated via a further control, not shown.

The proposed method makes it possible without using filter aids such as Diatomaceous earth, perlite, etc. difficult to filter yeast Beer mixtures, especially gellies perfectly to separate by filtration in yeast and beer. Here the filter capacity is used optimally because it by the surprising result of having one Primary floating from fermentation cellar yeast onto the filter cloths is now possible, the trub room in one Make optimal use of filter press.  

So it is no longer necessary to get heavy filterable tray with cake thicknesses up to 5 mm to satisfy. With the Ver cake thicknesses are reached, which essentially correspond to the trub space depth. Thus an increase in the amount of yeast to be filtered per Filtration cycle or per unit of time reached.

The increase in dry matter content is also a consequence of the proposed procedure. Which he Ranged values are 28% -33%. This is over enough for an automatic cake drop when Empty the filter press. Thick porridge yeast cakes with a cake thickness of up to only 5 mm, like them hitherto when filtering difficult to filter Bearings were a thing of the past.

Claims (4)

1. A method for the filtration of a beer-yeast mixture which is difficult to filter, in particular from a brewery, in a filter press with filter chambers or membrane filter chambers arranged one above the other or one behind the other by filter cloths in a filter frame, characterized in that a primary layer of yeast at the beginning the filtration is washed onto the filter cloths and that during the subsequent filtration a beer-yeast mixture of fermentation cellar yeast and lees is filtered in different proportions and different qualities. 2. The method according to claim 1, characterized, that to form the primary layer liquid, with beer enriched fermentation cellar yeast is used.   3. The method according to claim 1 or 2, characterized, that the primary layer at least with the Fil speed is washed ashore. 4. The method according to any one of claims 1-3, characterized, that the gelatin of the liquid, with beer enriched fermentation cellar yeast is added.