Study On The Urban Sewage Treatment Plant Process

This dissertation focuses on a city sewage treatment plant phase ii project as an example, in order to adapt to the sewage quantity growth, expand the scale of sewage treatment plant production, increasing its ability to sewage, reduce the pollutant emissions into the river and downstream of the river basin, protection of water resources, improve the water environment.Analysis of sewage treatment plant and stable operation of feed water quantity, water quality parameters, reasonably determine the scale and quality index.To ensure the water quality standards, reduce pollution as the first element.Choose the optimal, the most reasonable reconstruction scheme, reasonable structure form and process parameters, strive to advanced and mature technology, good treatment effect, safe and reliable running, high efficiency and energy saving, economic reasonable and reduce engineering investment and daily operation cost.Upgrade process selection and equipment selection with high efficiency, energy saving, stable and reliable as the core, is advantageous for the management and maintenance, easy to maintenance.Through the comparison of sewage and sludge treatment process, the sewage treatment plant under the second phase selection process for sewage sludge treatment:(1) the selected process for secondary of intensive processing process + deep treatment process, and the auxiliary chemical phosphorus removal.The whole process both targeted and harmonious and unified.In the main process on the basis of combining a variety of reinforcement process, each part process optimization combination, smooth, easy to operation and management, and ensure the water quality standard, in the domestic leading level.(2) the water quality of this project as A standard, higher demands on N, P removal.The selected A2 / O process biological reaction with high efficiency, N removal effect is good, to ensure that the total nitrogen and ammonia nitrogen emissions standards;Auxiliary chemical phosphorus removal combined with supernatant phosphorus removal, to ensure the water quality standards of P;The filter cloth filter to ensure that the SS discharging standard.The whole process of pollutants removal effect is good, reliable operation.(3) the sludge treatment process using mature, most domestic application of temperature in the digestive process, this process not only can provide energy for gas drag blower, and can be reserved for the future implementation of emerging thermal hydrolysis process upgrade space, design into the digester by 6%, the sludge concentration pool type with coordinated with oval digester, mixing with biogas;To meet the requirements of the subsequent disposal of the sludge, the use of plate and frame filter press as the depth of the sludge dewatering equipment, the factory dehydrated sludge depth below 60%.