VARIETY AND COMPARISON OF WASTEWATER TREATMENT SYSTEMS – I PART
Bathtubs, sinks, water-closets, washing machines, and dish washing machines outlet rivers of used water – wastewater.We must treat the used water. Domestic wastewater becomes a problem which must be solved in a best possible way. Let’s not judge the ones who say “After me the flood”. Even it is the wastewater flood. There are still people believing the best way to get rid of wastewater is to let it flow into a concreted bottomless neighboring pit.However this is a crime to your neighbors and nature.Use the facilities in a civilized manner.
What shall we do with wastewater?
1. Wastewater can be accumulated in underground reservoirs. Reservoirs feature various capacities, they should be selected according to the volume of wastewater; however if you are outleting wastewater into such reservoir, you must periodically hire someone to take away the accumulated wastewater to the utilization plant. The frequency of such services depends on the volume of wastewater.2. you can install a wastewater treatment plant. However the offer of wastewater treatment plants is very varied, therefore you must think well, before buying one.
Wastewater treatment plants
Technologies are constantly developing, however generally wastewater treatment plants can be classified into aerating and anaerobic (also called septic systems). Such wastewater treatment plants are often applied for treatment of domestic wastewater. Anaerobic wastewater treatment plants (septic systems) can be imagined as the system of “several wells” – wastewater flows from one reservoir to another and is gradually filtered. These systems do not require power or any maintenance, however the treated water does not comply with environmental requirements. Usually such systems require additional cleaning – filtering with specially installed soil or plants, or other treatment facilities (e.g. filtration well).Although this plant is based on very simple, even natural method – penetration via soil, using its filtration potential, however it usually disappoints the ones who select this kind of wastewater treatment plants. The mounting of simple system also requires skills and knowledge, whereas the self-made equipment usually pollutes the soil and ground water. Another significant disadvantage of such plants is greater area, required for installation of septic systems. Sanitary safety zones must also be increased. Despite such wastewater treatment plant operates unattended, its efficiency can not be increased in case of increased volume of wastewater. Supervision of protection of soil from pollutants is also complicated. Constant fermentation, zymosis processes increase the likelihood of unpleasant odor. The lifetime of such wastewater treatment plant is relatively short – approximately five years, after this period you should install a new wastewater treatment plant and manage the old one. These are the reasons, why the installation of such wastewater treatment plants is more complicated in both legal and environmental aspects. Therefore more and more owners of individual houses choose biological wastewater treatment plants. Aerated and biological sewage treatment plants enable to clean the wastewater outlet into the pipes. The water resulting from treated wastewater can be used repeatedly – it complies with all environmental requirements. Such water can be released into the soil, open water bodies, or it can be accumulated and used repeatedly, e.g. for watering of lawns or carwash. However such high quality of treated water can only be obtained by wastewater treatment plants, certified by notified laboratories, approving the requirements for wastewater treatment plantsThe title of these system highlights air supply is required for these plants, ensuring the existence of bacteria participating in the wastewater treatment processes; for this purpose, electricity is required. Power consumption depends on the capacity of air blast. Occasional removal of accumulated sludge must also be calculated into operational costs.
Operation of biological wastewater treatment plants Wastewater is outlet via pipes to the biological treatment plants and is treated in a several stages; active fragmentation processes ensure the treated water is clean again. Wastewater is outlet via pipes to the biological treatment plants and is treated in a several stages; active dissociation processes ensure the treated water is clean again.1. wastewater is outlet via pipes to the latticed opening (designed to stop mechanical and plastic impurities) and reaches the reservoir of biological treatment plant. Wastewater is enriched with organic contaminants, remains of food, grease, as well as various chemical impurities – washing powder, various cleaners, soap, etc. Water is cleaned in several important stages.2. in anaerobic (airless) fermentation zone, deterioration of organic matter, e.g. remains of food, is processed;3. The generated matter mixes with active sludge (where the plantation of bacteria is flourished) and reaches denitrification zone, where bacteria turn the nitrates into nitrogen gas which is released into air (similar reaction happens with phosphorus). Kitchen and toilet wastewater are also enriched with nitrates.4. The following is aeration zone, where wastewater is saturated with air using an air blast. In this zone, chemical dissociation – nitrification is performed.5. Subsequently liquid outflows via funnel-shaped opening into the bottom of sump, passing the layer of compressed sludge and out-flowing from the plant. The treated water can be accumulated and re-used for watering of lawns, flowers, carwash, or it can be outlet into reclamation trench, etc. We must ensure the water outlet into the environment is properly cleaned and complies with all environmental requirements. This can only be guaranteed with certified biological plants certified with CE conformity marking of European Union.