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The Value of Water

STICHWEH Wastewater Purification by means of Water Treatment Systems

The theme of World Water Day 2021 is valuing water.
Under this theme, the United Nations is calling on people to think about the vital importance of water and its value. This goes far beyond the financial aspect and also includes the ecological, social as well as cultural value of water.

Water is the basis of all life and an essential commodity. Water is a finite resource whose value first has to be recognised in order to be able to appreciate and safeguard it.

STICHWEH, the company based in Lower-Saxony, provides plant technology and preparation systems for the stone and quarry industry worldwide. Water also plays a key role here, right from the extraction process through to the classification of sand and gravel in accordance with best industry practices.

In gravel plants, waste water is produced during many technical processes like, for example, when bucket wheels or a log washer are in operation. Water treatment entails additional costs and extra effort. It is, moreover, subject to strict regulations and guidelines.

These requirements mean that the gravel plant operators are sometimes forced to purify their wash water in such a way that it can be used as wash water again. To ensure that this succeeds, it is possible to use wastewater treatment plants that remove the sludge and subsequently feed the clear water back into the washing cycle.

So, in screening machines, for example, the water is suffused with such high quantities of sand that it has to be treated separately once again either by means of cyclones or fine filters in order to effectively remove the solids in the wastewater. Only then can this water also be fed into the wastewater treatment plant.

STICHWEH, of course, likewise provides efficient wastewater treatment systems for its plants as well as expert technical advice and delivery. 

These treatment systems are built and delivered in collaboration with renowned suppliers and cooperation partners.  Fine sand recovery using fine sand bucket wheels is a special STICHWEH technology that is used as an important preliminary stage at wastewater treatment plants.

This is because even state-of-the-art wastewater treatment plants or water treatment systems work most effectively if the smallest sand particles have been removed in advance. The entire wastewater purification process can (thanks to the now absent fine sand particles) then be carried out in a way that very much protects the components and results in very low wear and tear.

Therefore, constructors of wastewater treatment plants generally aim to have as little sand as possible in the wastewater treatment process. However, if the concept for the treatment plant means that its design has to be small then a certain quantity of fine sand will actually be used to increase the advantageous compressibility of the sludge, which will now be suffused with sand. This is because, during the pressing process, the sand that is still present opens up extremely important cavities so that the water can flow out more smoothly and easily through the so-called ”filter cake“.

The long pressing times for the sludge can thus also be considerably shortened.  The sludge is pressed through filters so that, at the end of the pressing operation, only solids with low water content remain.

More information:

Fine sand washing and fine sand recovery STICHWEH bucket wheel

Solid and liquid separation STICHWEH pumps & cyclones

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