Vespa, Salher’s Dissolved Air Flotator, a sales success

Mar 24, 2021

Since its launching in 2018, Vespa, the dissolved air flotation unit developed by Salher, has been incorporated in wastewater treatment plants all over the world. You will find all the information concerning Vespa’s characteristics and operation here.

Vespa is a physico-chemical system used to separate suspended particles from the liquid to be treated by means of air micro-bubbles in a supersaturated concentration. The lighter particles adhere to the microbubbles as they float upwards to the scraping system, while the heavier particles settle to the bottom for later extraction by means of a pneumatic system.

This DAF is normally used as an advanced primary treatment in Salher water treatment plants, but can also be used as a final clarifier.

Why buy Vespa?

  • It removes up to 90% of oils, greases and suspended solids and up to 80% of BOD5 and COD.
  • Cylindrical, modular and compact, Vespa can fit in an infinite number of configurations.

  • Tailor-made design, height adjustable by means of adjustable legs.

  • Robust equip.

  • Easy to transport.

  • Very competitive price.

  • Application of basalt in the manufacture of its materials.

  • Manufacturing reliability, 100% European.

  • High purification performance.

  • Short delivery times.

  • Salher reliability, a company with 40 years of experience.

Cylindrical and ultra-resistant design

In order to manufacture this equip, Salher uses a GRP with isoltalic resin, which prevents corrosion and protects against UV radiation, providing the equip with total chemical and mechanical resistance to any type of adverse situation. All the metallic elements of the equipment are made of AISI 316 stainless steel.

When we talk about customised cylindrical design, we mean that its height can be designed to meet the needs of each client. Vespa also has a levelling system with adjustable legs for cases where the floor is uneven.

Vespa includes an adjustable clarified water collector so that the equip can easily adapt to changes in the loads and flow rates of the incoming water, and incorporates a transparent cover to reduce the escape of possible odours generated by the process and make it easier to visually check the inside of the unit. The sliding section facilitates maintenance work.

This DAF is a compact solution that meets the international dimensions of maritime containers, for shipment to any location in the world, and can even be adapted to existing treatment plants.

Flocculation system

The Vespa system has a flocculation pipe to achieve the chemical conditioning of the water made of thermo-welded HDPE, which offers greater resistance to chemical deterioration. Its structure is made of painted steel with C5-M corrosion protection (maritime protection grade) and has a levelling system.

Top brand panel board

The Electrical Department of Salher supplies Vespa fully automated by means of a SIEMENS PLC with colour touch screen. In addition, for remote visualisation and control of the installation, the control equipment of the treatment plant offers the option of a remote station with SCADA or GSM.

The programming of the panel board and the dynamic interface of the different screens facilitate the understanding and correct use by the operators in the plant.

Polyelectrolyte preparation system

Vespa includes an automatic system for the continuous polyelectrolyte preparation (UAP) and the addition of flocculant, coagulant and pH control and regulation.

This system consists of a hopper, an AISI 316 dosing auger, an agitator and a conditioning tank manufactured using the filament winding system, using isophthalic resin and glass fibre. This technique improves the mechanical and chemical properties of the tanks manufactured using conventional systems.

Vespa in international projects

See the international projects for urban and industrial wastewater treatment, reuse and drinking water treatment plants in which Salher has included its DAF, Vespa

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