What is AWAaerob?

STRATE AWAaerob is the aeration system for high-pressure sewage pipes. The 21% oxygen-containing air we breathe is injected into the sewage in the form of fine bubbles through an injector driven by a compressor. An additional possibility with the STRATE AWAaerob aeration plant is the emptying of the pressure-pipes by compressed air flushing (e.g. for seasonally operated equipment).

Oil-free pumps are used because it is the only certain means of ensuring that no oil mist enters the sewage. Checking of oil levels, oil changes and disposal of used oil are no longer necessary.

Condensate draining is automatic when equipped with a pressure vessel. Good sound insulation is all part of this clean and environmentally friendly system.

Why AWAaerob?

Due to the long lag-time of the sewage in the piped-system the oxygen it originally contained gets used up through bacterial demand. The resulting anaerobic condition leads to the formation of hydrogen sulphide (H2 S) a toxic and noxious gas that can form sulphuric acid (H2 SO4 ) in combination with oxygen. The consequences of all this are malodours and corrosion of pipes, installations, pumps and fittings. Moreover the treatment of the sewage in the treatment works becomes more difficult. Fitting STRATE AWAaerob prevents this condition arising by raising the oxygen level sufficiently to maintain the level as far as the pipe outlet.

When is AWAaerob appropriate?

The solubility of oxygen in liquids increases with increasing pressure. Aeration of this sewage is, thus, only effective in the pressurised pipeline. As it is not possible to regenerate sewage that already contains hydrogen sulphide by aeration at any point in the pipeline it is necessary to install suitable apparatus at the inlet-end.

It is advantageous to use pumping systems with small holding volumes, small amounts of residual water and without a layer of scum (see STRATE system AWALIFT). This prevents the premature fouling of sewage in the pump system due to timely pumping into the pressurised system. Once installed STRATE AWAaerob is effective and keeps the sewage fresh for an unlimited time.

How economical is AWAaerob?

Compressed air is an energy medium with which it is possible to be exceedingly economical. It is, therefore, important to check whether expensive flushing of the pipeline is necessary. The economical solution is aeration of the pressure system in the pumping station or at one and/or another of the deeper points in the pipeline system. With appropriate adjustment the amount of aeration can be matched to the prevailing conditions and kept as low as possible.

The energy costs for the aeration of 1m³  of sewage are only fractions of a penny, as a rule.