A downflow denitrification filter making by sand medium is designed for feeding

Question

A downflow denitrification filter making by sand medium is designed for feeding with secondary effluent to achieve effluent TSS and NO3-N concentrations less than 5.0 and 2.0 mg/L respectively. At 15oC operation, the NO3-N loading into filter is selected at 1.3 kg/m3day and the filter depth is 1.5m.

Given that with the following wastewater characteristics: Flowrate = 7000 m3 /day TSS = 25 g/m3 NO3-N = 20 g/m3 Temperature = 15oC

(i) Determine the filter size dimension based on the NO3-N loading (assumed it is a square type filter)

(ii) Determine the total amount of solids being trapped by this filter (assumed the total amount of solids is contributed from only 2 parts, i.e. filtered TSS and the active biomass growing under the methanol (CH3OH) addition):

Parameters given: Synthesis yield with methanol = 0.18g VSS/g CODutilized VSS/TSS =0.85 g COD/g CH3OH = 1.5 g CH3OH /g NO3-N = 3.2

Explanation / Answer

A]Flowrate = 7000 m3 /day

TSS = 25 g/m3

NO3-N = 20 g/m3

Temperature = 15oC

filter depth is 1.5m

.Synthesis yield with methanol = 0.18g VSS/g

VSS/TSS =0.85 g COD/g

CH3OH = 1.5 g CH3OH /g

NO3-N removal=[ (25-2.0)g/m3*(7000m^3/d (1kg/10^3)}

=161kg/d.

the NO3-N loading at 15 degrees C is 1.3 kg/m3day and the D depth is 1.5m.

Volume={161kg/d.} /1.3kg/m3.d

=123.8m3.

AREA=volumedepth

=123.8m3./1.5m

=82.5m2.

square dimensions=82.5m2

=20.6m2

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.