Even better performance in the aeration tanks

Highest efficiencies for blower technology and load profiles are in line as well as most efficient operation of wastewater treatment plants - AERZEN new machine control system makes this possible.

Approximately more than 70 percent of operating costs of a wastewater treatment plant are related to energy costs, arising when the aeration tanks are provided with air. The unique combination of AERZEN blower, turbo and hybrid technology has offered the best and most efficient solution in the industry until now. However, with AERsmart, the new control combination from AERZEN, performance can now be sustainably increased even further. With this new overall efficiency, which is very close to the optimum, additional savings of up to 15% can be achieved.

The load operation in organic wastewater treatment plants is subject to considerable fluctuations. Effluent flows and the degree of contamination may vary depending on the region, the time of day, the day of the week, the time of year or the quantity of precipitation – and this variation can be quite significant. With its high-performance compressors Delta Blower, Delta Hybrid and Aerzen Turbo, AERZEN offers a unique portfolio for the oil-free oxygen supply of the aeration tanks for this field of application. Thanks to the diversity of product types, these three packaged units are tailored to the requirements specified by various plants. This combination guarantees a performance, which is designed to meet precisely the demand of changing load profiles - from base loads to supply peaks! Each technology, regardless whether it is a displacement machine or a turbo machine, has its strengths and weaknesses. With the focus on energy efficiency, the nominal point of the turbo blowers cannot be beaten. The control range is approximately between 40% and 100%. In case of part-load operation, turbo machines are less efficient. On the other hand, displacement machines, such as Delta Blower and Delta Hybrid are ideal for part-load operation. They are strong in high control ranges between 25% and 100% and have good efficiency, also in part-load operation. The advantages of using three high-performance technologies within a combined system are these: highest energy saving, best control range and lowest investment costs. Thanks to the savings of up to 30% and depending on the plant, the conversion pays for itself in as little as 2 years!

The innovative machine control system AERsmart is the intelligent component, which arranges volume flows amongst the machinery in a mode that low, medium and high loads can be processed efficiently as per existing configuration, whereby the characteristic diagrams and the efficiency levels are integrated in the algorithm of the control system. As a consequence, the installed machinery is operated very close to the theoretical highest efficiency level. Even third-party products can be controlled via the overriding control system. AERsmart can arrange for the highest efficiency by a perfect interplay of up to 12 machines - for efficiency close to the optimum like never before.

AERsmart operates as follows: The required oxygen volume is transferred to the AERZEN machine control system as setpoint value e.g. as 4-20 mA signal or via bus connection.  AERsmart allows interaction of the existing machine configuration, leading to an oxygen supply of the aeration tanks along the required load curve in an efficient way like never before, very close to the optimum. AERsmart is the first master machine control system for the efficient combination of different machine technologies, no matter if the wastewater treatment plant is being operated with positive displacement machines or with turbo machines. Furthermore, unit data including pressure, volume flow, temperatures, energy consumption and fluctuating loads, as well as the machine data including service intervals, can be recorded sustainably and transferred to the control centre or other systems for further processing. So, changing requirements and possible ageing effects of the aeration system can constantly be monitored. This creates unprecedented transparency over the entire life cycle and provides the possibility for targeted measures.

Finally, AERsmart also convinces because it operates fully in line with new guidelines from the DWA (German Association for Water Economy, Waste Water and Waste) for the energy efficiency and energy analysis of wastewater treatment plants. And besides, as an intelligent interface, it is already pointing the way to Water 4.0.