COMPLIANCE INFO - Laserfiche WebLink

Home Browse Search

ADVANTEX' O&M MANUAL Appendix: The Nitrogen Reduction Process and Key Indicators The Process dons that play a role in the sizing of the filter Nitrogen removal(or"nitrification/deniaifica- unit. tion')is a biochemical process in which ammo- Performance Indicators nia is converted to nitrate(nitrification)(2NH3 To the nitrogenreducin ce(or converts to 2NO3+3110)and then reduced !u -reducing _ through bacterial action(denitrification)to nitro- potential)of any wastewater treatment system, gen gas,which can be released harmlessly to the be sure to check the following performance indicators: atmosphere, Clear, Odorless Effluent — Simple,see and During the nitrification process,about 9 party sniff"tests can be performed easily in the field. oxygen are consumed in converting 2 parts went from packed bed filters(rearculaung ammonia to nitrate.Therefore,depending on the textile filttrs,recirculating sand filters;W ermit concentration of ammonia,a considerable tent sand filters) that are performing well should amount of ail may be needed; Other processes, be dear(with turbidity:M NTUs*)and like biological(BOD) reduction,may occur odorless. simultaneously and further elevate the demand for aeration,especially if the organic level is high. Tests for Ammonia and Nitrate Nitrogen In an abundance of air,all the aerobic or-faculta- If your system is oxidizing ammonia to nitrate dve microbes compete for their shote of oxygen. (nitrifying),lab tests should masure relatively low ammonia levels and relatively high nitrate When the organic concentration is high,the levels in the filtrate.Because nitrification microbes that oxidize organic matter,primarily responds to many and varying conditions within the heterotrophic bacteria,are aggressive"and the aerobic treatment processes,ammonia and tend to outoompete other``are for the avail- nitrate nitrogen levels in the filtrate are the mos able dee oxygen in solution.The oxidation of ideal constituents to watch for any changes in ammonia is accomplished by autotrophic baste- performance.Start-up times can be plotted, opti- ria,which do not have as aggressive of a growth mum recirc ratios can be gauged,cleaning fire- rate,so if there isn't an abundance of oxygen, quencies can be predicted,and nonvisible dog- nitrification suffers.Consequently, the nitrifica- t !fig or saturation detected by watching either of ion process usually lags until the organic concen- these constituents. tmtion is depleted or until sufficient oxygen is present.At a 2.5:1 BOD/TKN ratio,the nitri- Typical nitrification in single-family residential fiers may only make up about 10 percent of the systems is expected to be in the 98-99°x6 range. microbial population.At 0.5:1 BOD/TEX the You'll want to investigate if the process appears to nitrifiers make up about 35 percent of the popu- degrade by 5 percentage points or more. lation. BOD The nitrification process requires Oxy- In a filtering process,the filter column must be gen,which is why nitrification is enhanced when deep enough,or the filter media must be efficient BOD is extremely low.Measures of filtrate BOD enough at filtering organic particles,to deplete should be<15 mg(4 although higher BOD may organic concentrations to a level in which a sufli- not necessarily correlate with low levels of nitrifi- dent population of nitrifiers will be sustained. cation. The physical(dimensional)features of the filter Typical influent characteristics are shown on p.7, i will vary depending on the medias characteristics When BODS is high,there is a greater organic —void ratio,moisture holding capacity,and demand for oxygen,which may hamper the 41 effective surface area per unit volume ratio. nitrogenous demand for oxygen.Increasing the Tankage,surge capacity,application rates,and recirc ratio should help establish oxygen balance. loading characteristics are other design considera- I