The water resources circularity and energy efficiency at the wastewater treatment plant of the seaport city

To use the Earth's limited resources in a sustainable manner while minimizing impacts on the environment, is the most effective way of the resources management. However, current European economy needs a lot of natural resources and cannot ensure sustainable development.One of the main challenges to Sustainable Development Goals on water, coastal and climate action face is developing and agreeing on human business/industrial activities from one side and coastal ecosystem resilience from another side. The analysis of the seaport city`s biggest enterprise regarding water supply and wastewater treatment area is reflected the real situation of water resource circularity with added-value products development. In this case, the wastewater treatment technological process was investigated. The important water quality parameters evaluation such as total nitrogen and phosphorus as well as BOD and COD were fulfilled. The level of pollution by heavy metals and other contaminants was estimated. The qualitative and quantitative characteristics of the sludge were measured. The estimation of the produced energy from sludge biomass was made. As a result, the innovation and recommendation for energy saving and digestates utilization were demonstrated. The comprehensive wastewater circularity model with existing and perspective benefits for sustainable water resources management was suggested.