Calculation and parameter specification selection of pipeline quality water supply system (3)

10.
4.
2.
7 Effective volume of clean water tank

The effective volume of the clean water tank can be calculated as follows:

V _j =Q _b -Q _j +600F _j +V ₁ +V ₂ (L)

In the formula, F _j is the bottom area of ​​the clean water tank, m ² ; V ₁ is the adjusted water volume, L, selected according to Table 10-3; V ₂ is the water volume used to control the automatic operation of the water purification equipment, L, calculated as follows:

V ₂ =Q _j /4K

In the formula, K is the starting frequency of the water purification equipment, generally <3 times/h
.

Table 10-3 Calculation of adjusted water volume

10.

(1) Store and adjust the amount of water in the high-level water tank

Pump flow: Q _b =Q _h

Pump head: H _b =h _o +Z+∑h

Where, h _o is the free head of the water tank inlet pipe outlet, m; Z is the geometric height between the water tank inlet pipe outlet and the water tank, m; ∑h is the total head loss of the pipeline from the water tank inlet to the water tank, m
.

Effective volume of clean water tank Vj:

V _j =Q _b -Q _j +600F _j +V ₂ (L)

Effective volume of high-level water tank Vg:

V _g =V ₁ +V ₃ (L)

In the formula, the calculation method of V ₃ (L) is the same as that of V ₂ (L), but K≤8 times/h
.

(2) The high-level water tank is only used for the automatic operation of the pump

Pump flow: Q _b =Q _h

Pump head: H _b =h _o +Z+∑h

The effective volume Vj of the clean water tank:

V _j =Q _b -Q _j +600F _j +V ₁ +V ₂ (L)

Effective volume of high-level water tank Vs:

V _g =V ₃ (L)

10.
4.
2.
9 Circulating water pump

Pump flow: q _b =q _x

Pump head: h _b = h _p (1+g _f /q _x ) ² + h _x

In the formula, h _p is the head loss of the circulating flow in the water supply pipe network; q _f is the water flow in the circulating state, L/s, taken as 0.
15qs; h _x is the head loss in the circulating return water pipe
.

For circulating pumps and water supply pumps that are also used for circulation, if the product head is significantly larger than h _b , measures should be taken to increase h _x to match the two
.

10.
4.
2.
10 The effective volume of the intermediate water tank of the water purification equipment

The effective volume Vm of the intermediate water tank of the water purification equipment can be calculated by the following formula:

V _m =600Fm+Q _j /12+V(L)

In the formula, F _m is the bottom area of ​​the intermediate water tank, m ² ; V is the circulating water flow, L, when the circulating water does not return to the intermediate water tank, take V=0
.

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4.
2.
11 Raw water tank volume

The raw water tank volume Vy is calculated as follows:

V _y =600F _y +Q _j /12+V(L)

In the formula, F _y is the bottom area of ​​the raw water tank, m ² ; V is the circulating water flow, L.
When the circulating water does not return to the raw water tank, take V=0
.

The tap water supply pipe of the raw water tank is generally designed according to Qh
.

Related Links: Calculation of Pipeline Quality Water Supply System and Specification Selection of Parameters (2)