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Suppose a certain kind of natural river is treated by coagulation and flocculation process in a reciprocating baffled flocculation tank. The water flow rate is 600 m3/h. Volume of the flocculation tank is 200 m3. There are 3 baffles in the flocculation tank. Assume that: the local headloss caused by all corners in the tank is 90% of the total headloss, and the local resistance coefficient of each corner is ζ=2.8. The average flow velocity in the corners is 0.2 m/s. Water temperature is 20 C. Water kinematic viscosity is ν=1.005×10-6 m2/s.Then, the average G is ___ s-1 (fill in an integer); The number of G is _ (choose in/out of) the reasonable range.

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Suppose the removal efficiency of TOC in water by a certain active carbon (AC) obeys Freundlich adsorption isotherm. The equation is qe=k Ce^(1/n), where k=0.006, n=1.1. The unit of qe is mg/mg-AC, and that of Ce is mg/L. Now, pump solution with 20 mg/L TOC into an adsorption column filled with such AC continuously.(1) When the adsorption column is completely saturated, the maximum adsorption capacity of AC is _ mg/mg-AC. (2 decimal places shall be reserved for the result.)(2) After that, solution with TOC concentration increased to 40 mg/L is pump into the AC adsorption column, then, the column _ (choose can/cannot) still adsorb the TOC in water.

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Suppose raw water is treated in a siphon filter. The water flow rate is Q=25000 m3/d. If the filtration velocity should be 10 m/h, the number of filter cells should be more than _ ;(Washing intensity is 15 L/(m2·s))and the corresponding area of each cell should be _ m2. Please fill in integers into the blanks.

Suppose a sedimentation experiment is conducted using a certain wastewater with suspended matter (SS) concentration of C0. The height of the settling column is 3 m. Take samples from the middle and bottom to determine SS as C, as shown below. Settling time (min) 30 45 60 90 120C/C0 In the middle (%) 30 20 15 10 7.5C/C0 In the bottom (%) 60 40 30 20 15 (1) The sedimentation type in the settling column is _ settling.(2) Assume water flow rate is 2000 m3/h. SS removal rate should be more than 85%. By the data above, the surface load of the settling tank should be _ m3/(m2h). The answer is an integral number. (Magnification coefficient is 1.5)(3) The settling area is approximately ________ _*1000 m2. (Please fill in an integer)