摘要
铸铁管广泛用于不同水质的输配,但是现存管道的设计并未考虑用于输送加氯消毒后的二级出水。通过现场试验,在一个长为68 m、内径为67 mm的模拟管路内,研究了加氯后管内壁生物膜的生长和脱落情况、消毒副产物THMs和HAA5的生成潜力以及对铸铁管的腐蚀程度。结果表明,管内壁生物膜的生长主要受控于水中有机物的含量;当投氯量增加到5.0 mg/L时,生物膜的生长和脱落不受影响;在投氯量相同的情况下,对污泥龄为5～12 d的二级出水进行加氯消毒,不会产生过多的消毒副产物,其中THMs和HAA5的最大生成量分别为40和10μg/L;加氯消毒对输水铸铁管的腐蚀主要受控于DO值而不是水中余氯的含量;腐蚀速率随氧化剂含量的增加而提高,但随余氯提高的速率要比随DO提高的速率小得多。
Ductile iron pipes are widely used for transmission and distribution of water with different qualities. The transmission of chlorinated secondary effluent is not considered in the design the existing pipe system. Based on field experiment, a simulation study was conducted with a pipe of 68 m length and 67 mm ID to assess the growth and detachment of biofilm, formation potential of disinfection by-products （DBPs） and corrosion effect on ductile iron pipe when the effluent is chlorinated. The results indicate that the biofilm growth in the pipe inner-wall is mainly controlled by the organic strength of the efflu- ent. When the chlorination dosage is increased to 5.0 mg/L, the biofilm growth and detachment is not af- fected. 5.0 mg/L chlorination of the secondary effluent with sludge age of 5 to 12 days does not result in any excessive DBPs formation, the maximum THMs and HAA5 levels in the chlorinated effluent are 40 μg/L and 10 μg/L respectively. The ductile iron pipe corrosion is mainly controlled by DO rather than residual chlorine. The corrosion rate increases when the oxidant increases, however the corresponding rate is much higher when DO increases.
出处
《中国给水排水》
CAS
CSCD
北大核心
2011年第11期55-58,共4页
China Water & Wastewater
关键词
二级出水
氯消毒
铸铁管
secondary effluent
chlorination
ductile iron pipe
