Minimised disposal costs thanks to maximised dewatering

Public sewage sludge

Public sewage sludge

The drainage characteristics of a sludge depends to a largely on its composition. The maximum dry substance (DS) achievable through mechanical methods is determined primarily by the content of extra-cellular polymer substances (EPS). The bound water can only be removed by denaturing before mechanical dewatering or by thermal drying.

With the Bucher press, the maximum possible dry substance content is achieved for both chemically untreated as well as denatured sludge.

Since the costs for sludge transport and handling are proportional to the weight of the dewatered filter cake, the disposal costs are reduced through the use of the Bucher press.

Industrial sewage sludge

Industrial sewage sludge

Processing of natural raw materials and feedstock to food or daily goods frequently uses huge amounts of water.

Before canned vegetables arrive on your desk it will be cleaned, peeled, blanched or cooked. The result of this process also is a lot of highly contaminated effluent. When wood is solubilized to pulp, paper, cellulose, textile fibre etc. highly contaminated water with dissolved side components of wood will appear.

Before a beef steak is on our dish, in slaughterhouses, at meat processing factories, processing stores for entrails, huge volumes of water are used. The side products from butcheries are processed to fat, oils, collagen and finally the skin is processed to leather in a tannery with highly polluted waste water.

Leaching of sugar beets or cane causes as much as effluent as the extraction of starch from corn, potatoes or crop.

From smaller processing factories the effluent is processed in a municipal Sewer Treatment Plant (STP), bigger processors run their own STP, which frequently have the same size as for a metropolis.

Microorganisms absorb the dissolved materials and they reproduce themselves by segmentation. In this way Surplus Activated Sludge (SAS) is created. Together with suspended solids from manufacturing process SAS forms the STP sludge. And this material must be incinerated in most cases.

To prevent the usage of much external, primary energy the sludge must be dewatered mechanically to the highest possible degree to keep the furnace running.

Many studies in (semi-)industrial scale showed the Bucher technology as the predominant benchmark.

The picture shows an installation in a considerable European Tannery.

If you are sitting on a convenient, skin friendly leather chair on a boat, in a car, in a train or airplane there is a high chance that a Bucher HPS has contributed to this feeling.

Drinking water sludges and hydroxide sludges

Drinking water sludges and hydroxide sludges

Drinking water production from surface water mostly needs settlement and filtration steps that generate sludge’s. That sludge includes chemicals (Metal hydroxides) and could not be returned anymore to the river.A nowadays modern drinking water plant includes a sludge dewatering step on site, using Decanters, belt-presses or press-filter. Despite common preconception those kind of sludge’s are quite difficult to dewater. In most cases decanters are not able to achieve high DS contents and Press-filters needs a lime addition to be able to work properly.

With the Bucher press, you will be able to achieve on those sludge’s the maximum possible dry substance through mechanical ways with or without lime addition. Sludge volume to evacuate could be reduce the half in comparison with other technologies.

Another significant benefit is that the Bucher Press works fully automatic, all around the clock and doesn’t need any manpower during the dewatering or emptying cycle.

The HPS Bucher Press offers you full automaticity combined with the best achievable DS content.

Effluent filtration in textile industry

Effluent filtration in textile industry

To separate solids from liquids, nonwoven or woven fabrics out of animal or vegetable fibers are used, and synthetic fibers are now in use since several decades. In cross-flow filtration the filtrate is recuperated transversely to flow direction through a porous wall layer. In classic filtration, a filter cake is built up on filter surface and this cake reduce the flow of filtrate which will depend of the cake permeability. Often it needs such a cake structure build-up in order to obtain a clear filtrate. The filtration of slimy products such as proteins, polymeric carbohydrates or microorganisms was with the classical methods of filtration is quite costly or even impossible.

The characteristic feature of the cross-flow filtration is the high flow velocity over the filter surface, which avoid the build-up of a cake.

Cross flow filtration may be sufficient to achieve a filtration efficiency for separation of fine inorganic particles of a few micrometers in a low viscosity solvent.