The energy-saving AEROSTRIP strip diffusers from Austrian company AQUACONSULT Anlagenbau GmbH are optimising one of the largest and most important wastewater treatment plants in Germany: the ‘Alte Emscher’ wastewater treatment plant in Duisburg's Hamborn district. It was built back in 1912 and was initially used for the mechanical treatment of wastewater for 120,000 PE. In 1988, the plant was rebuilt at its current location and equipped with a biological stage. Today, the treatment plant has been expanded for 500,000 PE and treats 90,000 cubic metres of wastewater per day. This wastewater comes from domestic and industrial dischargers, as Karsten Alfes, Operations Manager at the Duisburg-Alte-Emscher wastewater treatment plant, explains: ‘The steel industry and all its ancillary plants, which are located in the immediate vicinity of the wastewater treatment plant, are particularly noteworthy.’ The wastewater flows through the sewage treatment plant in free fall and then flows into the Rhine below the dyke. When the Rhine floods, the wastewater is pumped over the dyke.
More than 30 years after implementing the activated sludge process, the Emschergenossenschaft, as the operator of the sewage treatment plant, has now decided to change the aeration system: To strip diffusers in combination with turbo compressors. ‘The strip diffusers are part of the conventional activated sludge process,’ says Alfes. Energy efficiency, reliability and longevity are important when using them. Over 1,000 AEROSTRIPs were installed in the three basins of the ‘Alte Emscher’ sewage treatment plant. The modernisation also involved reinvestment in the existing turbo compressor station. The conversion was completed in 2021 - after around a year of operation, the results of the conversion have now been analysed: ‘By optimising the aeration system and renewing the existing turbocompressors, we were able to achieve energy savings of 4,000,000 kWh per year in the biological treatment stage,’ says Alfes. ‘Of course, that pleases our electricity meter immensely.’
Additional efficiency and safety thanks to ‘interlocking’ arrangement
‘The investment in our highly efficient AEROSTRIPs has therefore paid off,’ says a delighted Rüdiger Vrabac, Branch Manager at AQUACONSULT Anlagenbau GmbH in Germany: ’Especially in times when
energy saving is becoming increasingly important, this project shows where municipal power guzzlers can be effectively avoided. With AEROSTRIP, the costs run out of steam!’
A special technical feature of this wastewater treatment plant is the ‘interlocking’ arrangement of the strip diffusers, in which the individual elements of each diffuser field are supplied alternately from the left and right via separate air ducts. This extends the control range by a factor of 2, ‘Regardless of whether it is the night-time minimum requirement or the daytime peak oxygen demand: With this form of air supply, the strip diffusers operate in the optimum range for every load case,’ explains Vrabac. Of even greater importance for the system is the issue of reliability: if an aeration line is switched off in the event of a problem, only 50 per cent of a line - and not the usual 100 per cent - has to be abandoned.
AEROSTRIP® strip diffusers from AQUACONSULT Anlagenbau GmbH are currently in use in more than 2,500 industrial and municipal wastewater treatment plants worldwide. Thanks to ongoing research and development work and regular performance tests, the strip diffuser manufactured by AQUACONSULT under the name AEROSTRIP® can today be regarded as one of the most efficient representatives of fine-bubble deep diffusers. The AEROSTRIP® is manufactured exclusively at the company's Austrian headquarters in Traiskirchen (Lower Austria), where around 40 people are employed. AQUACONSULT Anlagenbau GmbH was founded in 1986 as a manufacturer of fine-bubble deep diffusers and became part of SANKI Engineering Co., Ltd. in 2006. AQUACONSULT's international partner companies have extensive engineering expertise and experience in aeration technology. A list of all international sales partners can be found on the product website www.aerostrip.at, information on AQUACONSULT can be found at www.aquaconsult.at
Contact:
AQUACONSULT ANLAGENBAU GMBH
Badener Straße 46
A-2514 Traiskirchen
+43-2252 41 481-0
office@aquaconsult.at
www.aerostrip.at