Analysis of the Influence of Low Temperature in Winter on the Nitrogen Removal Efficiency of Sewage Treatment Plants
In order to understand the effect of low temperature in winter on the total nitrogen removal efficiency of wastewater treatment plants in Hebei Province,the nitrogen removal process and measures of wastewater treatment plants in three coastal cities of Hebei Province were investigated and analyzed.The results showed the nitrogen removal efficiency of wastewater treatment plants in Qinhuangdao City,three coastal cities of Hebei Province,de-creased significantly in winter compared with other seasons.The average nitrogen concentration of the effluent in each season was 8.44 mg/L(winter),7.55 mg/L(spring),5.94 mg/L(summer)and 7.33 mg/L(autumn),respectively.Tangshan City(the actual mean total nitrogen concentration in each season was 7.76 mg/L in winter,7.21 mg/L in spring,7.64 mg/L in summer and 7.31 mg/L in autumn),and Cangzhou City(the actual mean total nitrogen con-centration in each season was 7.04 mg/L in winter and 6.82 in spring)mg/L,6.90 mg/L in summer,7.11 mg/L in autumn)nitrogen removal efficiency of wastewater treatment plants was little affected by seasonal temperature changes.Sewage treatment plants generally adopt thermal insulation or process optimization adjustment to mini-mize the impact of low temperature on the activated sludge system,and basically ensure that the effluent quality meets the discharge standard requirements of Grade A in the Pollutant Discharge Standard for Urban Sewage Treatment Plants(GB18918-2002).
nitrogen removalsewage-treatment plantlow temperature in winter
NETL
NSTL
万方数据
