Evonik is responding to the challenges of today's wastewater management with an innovative approach: The specialty chemicals company wants to specifically dope microorganisms that take over important material conversion reactions in the biological treatment of wastewater with oxygen. In this way, the efficiency of existing wastewater plants can be increased. Evonik is relying on its SEPURAN N2 hollow-fibre membranes to generate oxygen-enriched air. The Group is presenting its innovative technological approach at IFAT, the world's leading trade fair for environmental technologies, in Munich (May 30-June 3) at Booth 446 in Hall A4.
According to United Nations figures, more than half of the world's population now lives in cities. By 2050, more than two-thirds of people are expected to spend time in urban living spaces. The unstoppable urban growth raises questions about sustainability, quality of life and scarcity of resources and space. Considering this, intact water management is of vital importance. Evonik's innovative technology for efficient gas separation using membranes shows how this can be optimized for wastewater treatment.
Modern wastewater treatment plants rely on biology. Microorganisms take on important tasks across various purification stages: Bacteria, fungi and single-celled organisms absorb the components of wastewater as part of their metabolic process and thus purify the wastewater. "We can accelerate these processes by specifically optimizing the living conditions of the microorganisms. This enables them to grow faster and work more efficiently," says Dr. Jörg Balster, Head of SEPURAN Process Gases at Evonik. "We dope bacteria with oxygen, so to speak, which we obtain locally using our membrane technology and feed selectively."
Based on the same SEPURAN membrane technology, another gas from the air - nitrogen - can be added to the upstream solids separation to again slow down the growth of the microorganisms. This allows more nutrients from the pre-treatment to enter the biology. "With our membranes, we are able to precisely determine the biochemical boundary conditions per wastewater treatment stage. In this way, plant operators can run their processes much more efficiently and expand plant capacities without requiring large-scale construction," Balster adds.
Another gas separation membrane from Evonik-SEPURAN Green-also makes it possible to purify the biogas that accumulates during wastewater treatment processes into high-purity biomethane and return it to the circular economy. The CO2-neutral gas can be fed directly into the municipal natural gas grid or used as a green fuel (Bio-CNG) to power municipal vehicles.
"Our advanced membrane technology solves some key challenges that municipalities are already facing today. We believe our products can play an important role in smart wastewater systems and in the energy and mobility transition," says Volker Wehber, Head of SEPURAN Green at Evonik.
SEPURAN membranes make it possible to separate gases such as methane (CH4), nitrogen (N2), or hydrogen (H2) from gas mixtures particularly efficiently. The advantages of Evonik's membrane technology are the more precise separation of gases and higher productivity than other membranes on the market today.
SEPURAN membranes form just one part of Evonik’s comprehensive portfolio for customized solutions throughout the wastewater treatment process. Industrial or pharmaceutical wastewater, for example, can be pre-treated with HYPROX, a specialised hydrogen peroxide that breaks down non-biological contaminants in an advanced oxidation process (AOP). VIGOROX and PERACLEAN peracetic acid solutions for effluent treatment make short work of microbes and pathogens. Yet after doing their job, all of these powerful oxidants then quickly break down into harmless substances that do not interfere with subsequent biological processing steps.
