Innovations for industrial water treatment

Interference section for ozone in a large project in the paper industry, in which HAGER + ELSÄSSER implemented their new AOP process.

Vacuum pumps and ozone generation in a large paper industry project, in which HAGER + ELSÄSSER implemented their new AOP process.

Hager + Elsässer (H+E) is one of the world's leading solution providers for comprehensive water management. At Achema 2015, the company will present its processes for the cleaning and reprocessing of wastewater from production plants. This provides H+E with answers to challenges faced by industrial companies, stemming on the one hand from a growing market for higher-quality products and on the other hand from tightened emission limits. With a newly developed, self-created process in the ZLD (Zero Liquid Discharge) sector, H+E offers a particularly cost-saving, environmentally friendly, and space-efficient alternative to conventional plant technologies for optimal water cycle closure in industry.

This is a compact and holistically designed process combination for implementing material cycles aimed at wastewater-free production. The technology can be used across all industries such as chemicals, mining, petrochemicals, power plants, metal processing, or the food industry to produce clean to ultra-pure water.

The advantages include, among others, the high robustness of the system and a significantly reduced energy requirement. The specified limits for water, concentrates/waste, salt concentrations, valuable substances, acids, and caustics can be reliably maintained with the new process. Furthermore, the overall system is smaller than conventional ZLD processes, reducing investment costs by around 20 percent. The system is also designed to significantly shorten assembly and commissioning times.

In addition, H+E will also present its optimized AOP process at Achema. AOP stands for Advanced Oxidation Process and refers to a method for treating wastewater streams that are resistant to simple biological degradation processes. This is the case, for example, in the paper and pulp industry, where increasingly more bleaching processes are used, leaving behind more stubborn residual substances in the wastewater. AOP is also used in petrochemicals, where biotoxic components hinder wastewater treatment. Unlike other providers who rely on chemical total oxidation of difficult-to-degrade substances in such cases, H+E employs a combination of chemical and biological processes. In the first step, combined oxidants are used to make the substances biologically available, followed by biological filtration (technical name BIOFIT.F) to cost-effectively eliminate the now biologically available substances. As a result, the water again meets discharge standards, meaning the pollutants in the water are below the limits set by authorities. Compared to purely chemical cleaning, ozone input in the combined process is reduced by four-fifths; operating costs are accordingly lower. At the same time, the process developed by H+E, with reduced ozone and energy consumption, is more environmentally friendly. Its use at a large German paper mill was therefore supported by the Federal Environment Agency.