Wastewater Treatment Plants - Aquatec VFL, s.r.o.

Large wastewater treatment plants

AT 1000-5000 compact biological wastewater treatment plants
Compact biological wastewater treatment plants of the AT 1000 up to AT 5000 series purify sewage water from smaller municipalities and towns and from the sources of wastewater where sewage water is produced. After preliminary purification of organically contaminated wastewater, they serve as a degree of final biological treatment for meat-processing plants, slaughterhouses, dairies, cheese-dairies, wine-making plants, etc. Purified wastewater is further drained in the surface waters. The biologically purified wastewater can be finally clarified to the degree allowing it to be drained in sensitive areas, removing nitrogen and phosphorus.

Basic description
AT 1000 up to AT 5000 compact concrete wastewater treatment plants consist of two or several purification lines connected in parallel – biological reactors and a mud sump in a single unit and additional building premises and machinery devices (pumping station, mechanical preliminary clarifier, sludge management, tertiary degree of clarifying, instrumentation and control (I&C) etc.). A purification line – the biological reactor contains a non-aerated anoxic space, aerated oxic space, feeding space and a built-in retention space. The maximum achievable purification effect is based on the utilisation of low-load activation technology with aerobic sludge stabilisation. The AT wastewater treatment facility uses a tried and tested system of continual biological purification of wastewater with the integrated accumulation of abruptly inflowing water. This technology is protected in Slovakia by utility models UV 4324 and UV 2750 and internationally by patent No. EP1919833. Our purification technology ensures the high quality of treated water as well as low investment and operating costs. The technology is also known under the international name of Vertical Flow Labyrinth – VFL®.
The AT wastewater treatment facility is delivered based on a binding order, while payment and delivery conditions are subject to mutual agreement between the customer and supplier.

Purification process
It consists of a sequence of several technological processes. Wastewater being preliminarily treated mechanically is pumped into non-aerated, anaerobic-anoxic space, where nitrogen is biologically degraded and the conditions are created for the partial biological degradation of phosphorus. The non-aerated space is divided into several inner partition walls creating a vertical flow labyrinth, where internal circulation has been established.
Further, wastewater flows gravitationally into the aerated oxic space with low-loaded activation, where, under the presence of oxygen, organic contamination is biologically degraded and ammonia nitrogen is nitrified. The air is supplied to the aeration system by blowers with a side duct (high-pressure fans) or roots blowers. The pressurised air is blown into the aerated space through fine-bubble aeration elements. The pressurised air supplied through the blowers can be regulated by a time switch or frequency converter, which the wastewater treatment plant may use in various modes depending on loading. The streamflow regulator, which can be found in the feeding space, allows the use of the built-in retention space in the wastewater treatment plant in the event of abruptly inflowing wastewater, thus preventing the facility from being overloaded. Excessive sludge is thickened and stored in a mud sump. Sludge production is distinctly lower compared to other systems.

Technological parameters

The quality of purified water corresponds to the requirements of Directive No. 269/2010 of the Collection of Laws of the Government of the Slovak Republic on discharges into surface water. Guaranteed and commonly achievable parameters on the discharge from the wastewater treatment plant without tertiary clarification:

Technical parameters:

Technical and construction design of the wastewater treatment plant

• The facility is manufactured as a compact unit with the option of shape variation and modularity with a combination of water-construction concrete and a light thermo-plastic wall or structural elements in a single functional unit, which fulfils the task of balancing the variable through flows and achieving the highest possible efficiency of biological purification by removing nitrogen and phosphorus, which is not demanding in terms of attention or maintenance;
• Simple modular construction, by which it is possible to adjust to the gradual growth in the production of wastewater;
• Monolithic or prefabricated concrete tanks of water-construction concrete with circular, tetragonal and multigonal top views, where the bottom, exterior encasement, the partition wall between the non-aerated activation space and aeration activation space as well as the deflector are made of thermoplastic polypropylene based structural components.