Huber Solutions for Energy Efficiency in Wastewater and Sludge Treatment
Wastewater treatment is most important for the protection of our environment and for safeguarding our freshwater supply to ensure the health of the population.
However, wastewater treatment requires energy, predominantly in the form of electrical power for biological treatment of sewage, digestion of sludges and pumping sewage.
Around 10,000 German wastewater treatment plants consume over 4 billion kWh power per year at an annual cost of about 500 million €, over 15% of their operation costs. With the German energy mix for power generation, this results in over 2 million tons of CO2 emissions, which is about 0.25% of the entire German CO2 emissions.
More recent figures from the US are an annual power bill of $4 billion for operation of their 16,600 treatment plants, swallowing up to 30% of plant budgets, which is around 1% of the country’s entire power consumption. This results in CO2 emissions of over 45 million tons. Even with proven technologies, power consumption could be reduced by up to 30%.
Comparison of these figures shows that German plants are far more energy-efficient than American or British ones. But even here, much remains to be improved.
Of course, global energy consumption and CO2 emissions resulting from wastewater treatment are far higher than the above figures and are rising, as more and more wastewater is treated worldwide to an ever increasing standard. Implementation of energy-efficient solutions for wastewater and sludge treatment is an important contribution for capping of greenhouse gas emissions and mitigation of global warming.
HUBER engineers are continuously optimizing the energy-efficiency of their products and solutions. For example, the VRM bioreactor air sparges 1/8 of the membrane area for 1/2 of the depth at a higher intensity using less energy than the competitors air consumption for the same treatment.
HUBER engineers are working on integral computer controlled drives, pulsating washwater for economic use, energy recovery from sewage, generation of energy from sludge and many more ways to reduce the energy costs per litre of waste water treated. On the following pages we want to illustrate some energy efficient solutions, which should be considered by everyone connected in the Water and Waste Water industry.