Effects of seawater salinity on nitrite accumulation in short-range nitrification to nitrite as end product.
The effect of seawater salinity on nitrite accumulation in short-range nitrification to nitrite as the end product was studied by using a SBR. Experimental results indicated that the growth of nitrobacteria was inhibited and very high levels of nitrite accumulation at different salinities were achieved under the conditions of 25-28 degrees C, pH 7.5-8.0, and the influent ammonia nitrogen of 40-70 mg/L when seawater flow used to flush toilet was less than 35% (salinity 12393 mg/L, Cl- 6778 mg/L) of total domestic wastewater flow, which is mainly ascribed to much high chlorine concentration of seawater. Results showed that high seawater salinity is available for short-range nitrification to nitrite as the end product. When the seawater flow used to flush toilet accounting for above 70% of the total domestic wastewater flow, the removal efficiency of ammonia was still above 80% despite the removal of organics declined obviously (less than 60%). It was found that the effect of seawater salinity on the removal of organics was negative rather than positive one as shown for ammonia removal.
Yu
De-shuang
DS
School of Environmental Engineering and Science, Qingdao University, Qingdao 266071, China. hgdyds@263.net
Peng
Yong-zhen
YZ
Zhang
Kui
K
D000641:Ammonia / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism*; D009576:Nitrobacter / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D009606:Nitrosomonas / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D012623:Seawater / Q000032:analysis*; D012722:Sewage / Q000382:microbiology; D012965:Sodium Chloride / Q000032:analysis / Q000494:pharmacology*; D013997:Time Factors; D018505:Waste Management / Q000295:instrumentation / Q000379:methods*
D009573:Nitrites; D012722:Sewage; D012965:Sodium Chloride; D000641:Ammonia