Sludge drying beds | Voima Toolbox

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Leitos de secagem para lodo de esgoto sanitário

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Input data

Sludge daily production

Sludge concentration

Sludge height to apply in each bed - see note 2

Output data

Sludge produced each 28 days

Area needed for operating drying beds

Sugested number for drying beds(half in operation; half resting or being cleaned)

Suggested width for each bed

Suggested lenght for each bed

Total area for all operating beds

Sludge volume applied in each bed

Sludge volume applied in all operatingn beds

Total solids suspention load, in kg SS / m² - see Note

Description

Given the daily sludge production, its concentration and the sludge height to be applied in each bed, calculates, among others, the produced sludge volume, the needed area for the beds, the suggested number of beds and its dimentions. Drying bed

Notes

It is assumed that the sludge will be applied in a drying bed during 28 days, removed after 21 resting days and that the bed will be cleaned whitin 7 days. According to Brazilian Standard ABNT NBR 12209:2011:
Sludge height over the draining bed shall not exceed 0,35 m.
Drying bed shall be used only for stabilizad sludge.
The total area of the drying bed must be divided in at least 2 chambers. Maximum distance for manual transport of the dried sludge in the interior of the drying bed can not be greater than 10 m.
The sludge discharge into the drying bed can not exceed 15 kg SS/m² (total suspended solids / draining area) in each operating cycle, except in justified cases.
The use of syntetic geotextile fabrics in addition or substitution of sand must be justified.
Drying beds can be covered with good tranparency material.

Calculations