(5 points) Calculate the design discharge at node 1 under dry weather conditions and under wet.connected surface area (A) node 8 : 3 ha.connected surface area (A) node 7 : 3 ha.connected surface area (A) node 4 : 2 ha.connected surface area (A) node 3 : 6 ha.Peak wastewater production : 10 l/inhabitant/h.The system serves an urban area of 3000 inhabitants A pumping station and an overflow weirĪre located at the outflow node 1. The lay-out of a combined sewer system is given in figure 1. The design flow of the treatment plant can be determined with the following data: I) Draw a P& ID (process and instrumentation diagram), considering valves and pumps for the H) Explain the advantages and disadvantages of a sludge blanket clarifier in relation to the normal G) Calculate the surface area of the sludge blanket clarifier, assuming 10% space for theįlocculation unit and propose the number of reactors in parallel. 100Ī) Give the main functions of the reservoirs of the Biesbosch (also consult the water qualityī) Determine the hardness, the pH and the Saturation Index in the raw water of the reservoirsĬ) Determine the decay rate of E-coli in the reservoirs, assuming a total retention time of 100ĭ) Give (and argue) the type of chemical to be used for coagulation.Į) During flocculation flocs are formed with a density of 1010 kg/m 3 and a diameter of 100 μm.ĭetermine the settling velocity of the flocs (in m/h).į) Explain why the upflow velocity in the sludge blanket clarifiers can be 10 times higher than the Table 1 - Water quality of Biesbosch reservoirs For the flow characteristics see the text box below. Of storage, coagulation, sludge blanket clarification, rapid sand filtration, activated carbon filtration, UVĭisinfection, and clean water storage. Kn wall roughness in m Part 1 - Drinking waterĪt pumping station De Berenplaat the water is treated that is pumped from the three reservoirs in Deīiesbosch (where water from the river Meuse is abstracted). g Formule sheet CT3420 - Urban drainageįriction losses in a conduit (fully filled):.Table 4 – Composition of air in volume% at 10 ☌ and under atmospheric pressure (101325 Pa). Students are allowed to give their answers in the Dutch laguage.Ĭhloroform 0. Write your name and study number clearly on every answer page. Use a separate answer page for every part. Always give a motivation to your answer and ask yourself if the answer is complete and if the treatment process can be constructed in field practice. Added to this exam are the most important equations. The use of your calculator is only allowed for making calculations (not for consulting stored information). If there is something unclear in the questions please inform the supervisor. (YOU HAVE ONE HOUR PER PART) With every question you have to show that you able to determine the influence of process parameters so you can optimize the design and the operation of the treatment processes. Examination CT3420 – Sanitary engineering Date : 11 April 2012 Time : 9 - 12.

Q in peak wet weather calculator