Hidrológiai Közlöny, 2016 (96. évfolyam)
2016 / 3. szám - HISTORICAL SNAPSHOT - Juhász Endre - Major Veronika: Sanitation in Hungary
Endre Juhász & Veronika Major: Sanitation in Hungary 33 Mid-term goals of Hungary are (OVF 2014))'. • Reducing and preventing pollution of the environment • Protection and sustainable use of natural resources; water retention, storage • Promoting green economy • Promoting regional cooperation • Development of urban wastewater collection and treatment in the fields of technology, engineering and automation • Promoting sewage sludge utilisation as a renewable resource • Facilitating the move towers green economy characterised by low greenhouse gas emission • Increasing the efficiency of energy consumption and utilisation of resources • Increasing the share of renewable energy sources • Increasing resource efficiency of energy sources, sustainable use of resources • Sustainable use of properly treated wastewater, as a basic element, in regions characterised by drought • Developing the field of agri-environment, with special attention to soil conservation • Promoting sustainable agricultural use of sewage sludge • Environmental technology innovation • Finding adequate solutions for settlements where wastewater collection cannot be constructed efficiently, taking into account domestic conditions (cost efficiency, operation, financial support, sewage sludge disposal, etc.) FUTURE OUTLOOK Quote from Charles Darwin: „It is not the strongest of the species that survives, nor the most intelligent that survives. It is the one that is most adaptable to change. ” Following Darwin’s thoughts, we must adapt our water utility and sanitation to the climate change and to the economic rationality required by sustainability. We have to rethink old habits to deal with new challenges. The expected developments and trends in some decades to come outline concrete tasks for us. Implementing complete wastewater collection and treatment based on sustainability Based on current trends, complete wastewater collection and treatment in Hungary is expected by 2040 (OVF 2014). Especially for settlements below 2000 PE, elaboration of a legal-technical background that favours simple but environment-friendly solutions is very important. In case of bigger wastewater treatment plants the goal is reusing treated wastewater. Wastewater treatment plants are tomorrow’s energy and nutrient recovery plants The task of wastewater treatment plants is to keep the environment cleaner, but during the process they use significant amount of energy and chemicals, while treatment and disposal of sewage sludge is a problematic issue everywhere. Hungarian scientists answer these challenges with a patented technology. With this process, beside significant recovery of carbon, nitrogen and phosphorus, up to 50% reduction in the amount of sewage sludge, and 25-30% reduction in the plants energy consumption can be achieved. Nowadays, wastewater treatment gets more complex year by year. This new Hungarian innovation contributes to sustainable wastewater treatment with this patented technology. The patented technology uses controlled hydrolysis to decompose the excess sewage sludge in a thermophilic, microaerophilic bioreactor. During the process, organic material will be released as volatile (short-chain) fatty acids, ammonia and ortho-phosphate. The reduced amount of sewage sludge can be treated using anaerobic digestion or in a biogas plant utilising its carbon content to produce biomethane. Dissolved materials are separated using membrane and with a distillation process, volatile fatty acids can be recovered as distillate, while nutrients (N, P, K, S) can be recovered as concentrate. Volatile fatty acids are an important raw material for chemical industry, or can be utilised as readily biodegradable carbon source to enhance treatment efficiency, or to boost energy production. Nutrients (that contain other important microelements for plants) get back into their natural cycle. This way, our current wastewater treatment plants can be tomorrow’s energy and nutrient recovery plants (URL6). Water reuse Reuse of used water for irrigation, groundwater recharge or industrial purposes are well-known, decade- long practices. However, for many water users a simpler solution was to discharge treated wastewater into surface water recipients and to cover their water demand form surface water or groundwater. Water quality and quantity issues of the 21st century led us to the conclusion that wastewater treatment is part of an integrated, ecosystem-based water resource management system, where wastewater must be taken into account as resource. Figure 21 summarises the water quality produced by different levels of treatment. Economic efficiency and sustainability can be increased by using treated wastewater tailored to the future reuse.
