Sludge Dewatering Calculations

1- Selection of the #sludge #pump:

It is very important to set a proper sludge feeding pump comply with the treatment capacity of the #screw #press #dewatering #machine.

Calculation based on the selected model #benenv #MDS 311:

MDS-311（Settled #sludgetreatment capacity: 60kg-DS/h?sludge concentration:?10000mg/L）

conversion：10000mg/L = 10000g/m3 = 10kg/m3 = 10 g/L）

Sludge treatment capacity for MDS-311 is ：

60kg-DS/h?÷?10kg/m3?÷?60min/h?×?1000L/m3?＝?100 L/min

So for a concentration of 10g/L of sludge, the #sludge pump capacity should be 100L/min or 6 m3/hour.

The most common sludge pump used is the positive displacement screw pump.

2- Selection of the #polymer or #flocculant pump:

The dosage volume of polymer flocculant should be set as per sludge treatment capacity and sludge concentration.

Calculation based on the selected model #benenv #MDS 311 (60 Kg-DS/h):

Powder flocculants add rate is generally 0.5% for sewage sludge, under the condition of 1000 times dilution, the dosage of polymer?or flocculant per minute is：

DS treatment capacity *?add rate?* dilution ratio?* density?* unit conversion

60kg-DS/h?×?0.5%?÷?1/1000?÷?1kg/L?÷?60min/h = 5 L/min or 300L/hour.

The flocculant pump used can be a metering pump or a positive displacement screw pump.

3- Sludge cake Quantity calculation:

The dewatered sludge is called sludge cake.

To calculate the quantity of the of sludge cake, we use the following formula:

Quantity (T) * Sludge Concentration (%) ÷ (1- sludge cake moisture content)

Example:

Considering a sludge feeding capacity of 6 T/hour with concentration of 10 g/l, and the sludge cake moisture of 80%.

Q * DS(%) ÷ (1- sludge cake moisture) = (6 * 1%) ÷ (1-0.8) = 300 Kg/h.

Here's showing the importance of #sludge #dewatering before disposal, by reducing the volume and stabilizing it from liquid to solid state.