| 摘要 |
An activated sludge process for treating wastewater containing ammonia as a contaminant and further for treating wastewater containing ammonia as a contaminant and other contaminants which may possibly be present, including cyanide, thiocyanate, sulfide and/or organics, the process involving treating wastewater in the presence of an appropriate microorganism population acclimatized to the wastewater contaminants and their levels in the wastewater, this microorganism population including (1) nitrifying microorganisms capable of converting ammonia to nitrite, (2) optionally, nitrifying microorganisms capable of converting nitrite to nitrate, and (3) facultative microorganisms capable of denitrifying nitrite and/or nitrate by oxidizing organic material and converting nitrite and/or nitrate to free nitrogen, with the process operated under a series of controlled conditions to ultimately achieve in the activated sludge process a microbial conversion of ammonia to nitrite and/or nitrate and then to free nitrogen, i.e. a simulatenous nifrification-denitrification in a single reactor. …<??>The conditions controlled in the process include control of the sludge wastage rate, hydraulic residence time, dissolved oxygen level (DO), sludge mixing rate, biological oxygen demang (BOD), pH and temperature, as described hereinafter. Optionally, (4) other microorganisms capable of converting other contaminants such as cyanide and thiocyanate to ammonia and sulfide to sulfate can also be present. |
