Determine the NRC BOD removal efficiency for a two stage trickling filter plant based on the following: primary clarification with 35% BOD reduction, first stage filters loaded at 80 lb/1000ft3/day, intermediate settling, second stage filters sized identical to the first stage units, an operating recirculation ration of 1.0 for all the filters, final clarification of the effluent, and a waste water temperature of 18 c

Determine the NRC BOD removal efficiency for a two stage trickling filter plant based on the following: primary clarification with 35% BOD reduction, first stage filters loaded at 80 lb/1000ft3/day, intermediate settling, second stage filters sized identical to the first stage units, an operating recirculation ration of 1.0 for all the filters, final clarification of the effluent, and a waste water temperature of 18 c

Solid Waste Engineering

3rd Edition

ISBN:9781305635203

Author:Worrell, William A.

Publisher:Worrell, William A.

Chapter7: Thermal Processes

Section: Chapter Questions

Problem 7.12P

See similar textbooks

Similar questions

Design a trickling filter system for BOD removal without the nitrification requirement, to treat municipal wastewater with an average flow of 200 m3/d (Qin) and influent BOD of 200 mg/L and Ammonium (NH4-N) of 42 mg/L. Make appropriate assumptions and use the design indicators for plastic media filters as given below. What are the possible effects of the peak flow of 1.5 times occurring once in a month? Volumetric loading rate (Bv)= 0.5 kgBOD/m3.d Volumetric loading rate for NH4-N (Bv, NH4-N)= 0.2 kgNH4-N/m3.d Hydraulic loading rate (qh= Q/AR)= 1.2 m/h Recirculation ratio (Qr/Qin) = 0.5
A single stage super-rate trickling filter is to be designed for a population of 15 000 persons. Pertinent data are average influent flow = 350 L/cap-d, influent BOD5 = 250 mg/L, primary clarifier removes 33 % of the BOD5, effluent BOD5 = 15 mg/L, filter depth = 6 m, and recycle ratio = 2. Pilot-plant studies using a synthetic plastic packing material show a removal constant K = 2.26 at 20 oC when the depth is in meters, the hydraulic loading is in m3/m2-d, and the constant n = 0.5. the winter wastewater temperature = 10 oC. If two filters are used in parallel, determine the filter diameter in meters.
(c) A filter has a head loss of 0.30 m when clean and 1.30 m after 24 hours of filtration at a rate of 1.5l/s. . Estimate the following if the filtration rate is changed to 2 l/s i. head loss immediately after backwash ii. 10 hours later
A laboratory provides the following analysis obtained from a 600 mL sample of wastewater: total solids = 350 mg/L, total suspended solids = 210 mg/L, dissolved solids = 10 mg/L, and volatile dissolved solids = 90 mg/L. It was also recorded that the filter mass after drying at 103oC and after ignition at 550oC are 0.23 g and 0.135 g, respectively. Calculate the fixed suspended solids and total dissolved solids.
B) A plant expansion is planned for Urbana. The new design flow rate is 1.0 m® /s. A deep bed mono-media filter with a design loading rate of 600 m* /d - m * of filter is to be used. If each filter box is limited to 50 m” of surface area, how many filter boxes will be required? Check the design loading with one filter box out of service. Propose an alternative design if the design loading rate is exceeded with one filter box out of service.
A WTP is designed to treat 48,000 m3 / day. For filtration 12 RSFs are used, each filter is designed with 2 troughs of a square cross - sectional area. The filtration rate is 160 m / day and the backwash rate is 864 m / day. Find 1) Dimensions of each filter, Land W (m) with or without washing? Also filter depth? 2) Dimensions of each trough, y and b (m) and gullet? 3) Volume of water (m3) to wash 2 filters at the same time for 5 minutes?
Consider the single stage trickling flter plant from the solutionin Example 9.1. The use of a single stage fIlter produced a planteffciency of about 75%. To increase plant effIciency, the engineerdecides to add an identical second stage fIlter in series to the frstone. The wastewater fLow rate is 2000 m3/d with a BOD5 concentration of 400 mg/L. Primary clarifcation removes 30% of the BOD5.The filters are each 12 m in diameter and 1.5 m in depth. The directrecirculation ratio for each stage is 2.0. Wastewater temperature is20°C. Calculate the second stage hydraulic loading rate, organicloading rates, effuent BOD5 concentration, and overall plant effIciency. Comment on the advantages/disadvantages of using singlestage versus two stage trickling fIlters.
) A rapid gravity filter operating with an influent concentration C0 of 20 mg/l suspended solids has the clean bed filter coefficient λ = 0.003 mm-1. Given that C = C0e-λz where z is the media depth in mm and C the concentration at that depth: Determine the depth of media required to achieve 90% removal efficiency? (2 marks) Determine the depth required to achieve 99% removal efficiency? (2 marks) Determine the depth required to achieve 99.9% removal efficiency?
Design a rapid mono-media sand filter for a plant that has a design flow rate of 120 MGD. Filter Boxes Required:a) How many filter boxes are required for “on-line” filters?b) How many additional filter boxes are required to accommodate “off-line”filters?c) What is the total number of filter boxes needed by your plant?
A single-stage trickling filter is to be designed to treat primary effluent containing a BOD5 concentration of 120 g/m3 . The minimum wastewater temperature anticipated is 150C. Using a recycle ratio of 1.0, determine the minimum allowable BOD5 loading rate (kg/m3 ⋅d) for a stone-media filter, based on the NRC equation, if an average effluent BOD5 concentration of 30 g/m3 is to be achieved.
a) Determine the total GMF surface area required to filter a volumetric flow rate of 10.0 MGD at a filtration rate of 4.0 gpm/ft2 . Divide the total surface area into an appropriate number of filter cells and determine the planar dimensions if square cells are used. Determine the percentage of the filtered water that will be used for backwashing under the following conditions, Each filter cell is backwashed once every 24 hours • Backwashing rate of 20.0 gpm/ft2 • Each cell is backwashed for a duration of 10 minutes Also determine the filtration rate through the remaining filter cells when one cell is removed from service for backwashing.
Consider the design of granular media filters for a water treatment plant with a design flow of 40 MGD. For a filtration hydraulic loading of 5 gpm/ft2 determine the total filter area required for filtration (in square ft). Next, select the number of parallel filters needed, and their length and width (even foot increments), if each filter is square with area of 400 square feet. You choose a filter consisting of 36 inches of sand with an ES of 0.55 mm. The porosity is 0.4. Determine the superficial filtration velocity and the pore velocities in the sand layer. Calculate the detention time (in minutes) through the entire depth of the filter Calculate the clean bed head loss (in feet) for the filter using the Carmen-Kozeny equation. Assume a water temperature of 68 ºF and the design hydraulic loading rate. Use the media effective size for media diameter in the calculation. Estimate the filtration efficiency for a particle that is 4 microns in diameter.