Options - Consumer Sectors
The Consumer Sectors category contains the following properties:
- Coefficient k1 - Coefficient of the highest consumption day, normally 1.2
- Coefficient k2 - Coefficient of the hour of highest consumption, normally 1.5, applicable only in the initial flow
- Infiltration Rate - ABNT's NBR 9649 standard says:
"TI, Infiltration Contribution Rate, depends on local conditions such as:
- Water table water level
- Nature of the underground
- Quality of network execution
- Piping material and type of gasket used
The value between 0.05 and 1.0 l/s/km adopted must be justified.
"
- Minimum Flow (Qmin) - When calculating the flow flowing in any section, if it is lower than the minimum flow, it will be adopted.
A hydra valve discharges about 1.5 l/s, which is the default value adopted
- Coefficient of return (Ctr) Coefficient of return sewage/water
The return coefficient represents the fraction of the water that returns to the sewage collection system, the other part being infiltrated in the gardens or destined for rainwater galleries.
This methodology must consider the flow due to infiltration in the sewage collection network.
It varies according to the table below:
| Size
|
Ctr (%)
|
| Big Cities
|
85
|
| Medium Cities
|
80
|
| Small Towns
|
70
|
- Minimum Trative Tension (Tmin) - The flow of sewage through the pipe must be such that the trative tension of the sludge is greater than or equal to the minimum trative tension, in order to guarantee that it does not settle in the same.
In general, this value is adopted as 1 Pa (Pascal)
- Percapta consumption (q) Micro measured per capita consumption, normally 200 l/inhabitant/day
It can be estimated by the table below:
Porte of
community
|
Population range
(hab)
|
Per capita consumption
(l/hab/day)
|
| Rural village
|
< 5,000
|
90 - 140
|
| village
|
5,000 to 10,000
|
100 - 160
|
| Small locality
|
10,000 to 50,000
|
110 - 180
|
| Medium city
|
50,000 to 250,000
|
120 - 220
|
| Big City
|
> 250,000
|
150 - 300
|