We are continuously developing novel solutions to ensure vital raw materials will still be available in the future
With framework conditions forever changing, it is essential to constantly optimise procedures and develop new ways of treating wastewater. An important issue here is protecting raw materials. REMONDIS Aqua, therefore, develops state-of-the-art processes enabling it to efficiently recycle all residual materials generated, thus ensuring that the very most is made of the material and energy potential of the wastewater being treated.
Our philosophy: sewage treatment plants are no longer a place for disposing of waste materials but for recovering clean water, energy and minerals. By using REMONDIS' processes and services, the wastewater can be treated, the sewage sludge used for materials recycling or to produce energy and valuable salts recovered from the ash – in particular when the facility uses TetraPhos®, a process developed by REMONDIS Aqua itself.
With this new method, the sewage sludge ash is not dissolved in hydrochloric acid – the standard procedure – but in phosphoric acid. The phosphoric acid is enriched with the phosphorus contained in the ash and then processed in a number of different stages. This procedure produces a number of final products including RePacid® phosphoric acid for the production of phosphates (inc. fertilisers), gypsum for the building supplies trade, and iron and aluminium salts which can be returned to the sewage treatment plant to be used as a precipitating agent to treat wastewater and eliminate phosphorus. TetraPhos® is, therefore, an exceptionally efficient and cost-effective process that also contributes greatly towards conserving our planet's natural resources.
REMONDIS has, however, gone a step further. The ideal salt for recovering phosphorus is calcium phosphate, which can be produced at sewage treatment plants with ReAlPhos®. By using aluminium (e.g. ALUMIN®) as a precipitating agent, the phosphorus can be recovered from the sewage sludge in a more accessible form.
Phosphorus is an essential nutrient for all living organisms. It is, however, becoming increasingly more difficult to supply the volumes needed by agricultural and industrial businesses – primarily because reserves of this natural resource are becoming depleted and its quality is steadily deteriorating. The majority of the phosphorus used in the food chain is returned to the environment via municipal and industrial wastewater. In line with its goal to protect raw materials and create sustainable recycling processes, REMONDIS uses this source to recover phosphorus. To this effect, REMONDIS Aqua has developed the REPHOS® process for treating industrial wastewater with which the phosphorus can be recovered directly from the wastewater in the form of MAP (magnesium, ammonium, phosphate). The truly special feature of this patented method is that a further dewatering process is not required so that the MAP can be used immediately by agricultural businesses. This is, therefore, an innovative and efficient way of treating wastewater and conserving our raw materials at the same time.
Magnesium ammonium phosphate (MAP) recovered from industrial wastewater
"BioBZ", a project sponsored by the Federal Ministry of Education and Research, is carrying out research work into a completely novel system for sewage treatment plants that will contribute towards Germany's so-called "energy turnaround" – i.e. the country's switch from fossil fuels to renewables. A fuel cell is to be used here that is "run" on wastewater, with the microorganisms contained in the water acting as biocatalysts. Electricity will be generated as a result of the organic substances in the wastewater being biologically broken down. Six partners from a variety of fields – the world of science, the manufacturing sector, engineering businesses, sewage treatment plant operators and trade associations – have joined together to participate in the project. Our subsidiary, EURAWASSER Betriebsführungsgesellschaft mbH, is part of this group and will be helping by passing on our expertise in the area of municipal sewage treatment.
The overall aim of the project is to set up a pilot scheme in order to develop, investigate and evaluate such a bio-electrochemical fuel cell. Research work is to be carried out to examine what installation options are viable in a sewage treatment plant and the effect such a fuel cell might have on overall plant operations. We have introduced several measures in the past to make our sewage treatment plants as energy self-sufficient as possible – for example by replacing older equipment with more energy-efficient appliances. Thanks to BioBZ's research work, the sewage treatment sector will soon be well on its way to achieving its own "energy turnaround".
Project duration: 05/2014 - 04/2017
Many types of industrial wastewater – in particular those from the food industry – contain large volumes of organic substances which have to be eliminated. Traditional methods employed to do this not only require high amounts of energy, they also generate considerable quantities of residual materials. Thanks to its special reactor concept, REMONDIS Aqua is able to remove these organic pollutants from the wastewater and, at the same time, generate biogas in a particularly efficient way, contributing greatly towards protecting raw materials. The classic wastewater treatment facility is turned into a producer of energy. In many cases, far less energy is needed to treat the wastewater in this way than is actually generated in the form of biogas. Moreover, REMONDIS Aqua also provides flexible, bespoke solutions for the actual biogas itself adapting them each time to the specific needs of the business location – from transforming it into electricity in a combined heat and power plant all the way through to processing the biogas so it can be used directly to generate energy in the production facility. The RE2ENERGY® process is a plant and reactor concept which has been perfectly adapted to the requirements of wastewater treatment and the production of biogas. It helps to conserve our natural resources and is already being used by companies such as VALENSINA and Oettinger.
An anaerobic reactor is able to pre-treat wastewater and produce biogas at the same time