Wastewater Treatment With Sludge Drying Bed Techniques

The principle in handling this sludge is a method / system that functions to store liquid sludge. This system is divided into two systems, namely;
- Low air content mud,
- Filtrate / water, which must be returned to the process (initial / middle)

In this article, the writer divides it into two ways, namely;

1. Mechanical Way
As we already know, many manufacturers of wastewater treatment equipment in the world make equipment (machines) with sewage sludge treatment. Some of them are as follows;

• PRESS FILTER BELT
  In the use of this machine, the mud is clamped / squeezed in the middle of 2 porous belts by using high pressure roll clips,
• CHAMBER FILTER PRESS
  This machine is used by inserting the sludge into square bags with a porous frame lined with high pressure until the water is squeezed out and the solid mud is trapped in.
• CENTRIFUGE
  In principle, this method is the same, where the mud is inserted into a round tube in which there is a screw where the end of the tube is tapered / conical at the end. Likewise with the thread / screw distance / pitch which is getting tighter at the end side. Thus, the sludge will experience high pressure squeezing, which results in a separation between the mud and water.

2. Manual way

• SLUDGE DRYING BED (SDB)
  In this method, the process is to manually dry the sludge obtained through sunlight (Evaporation / Evaporation). Liquid sludge from the deposition building (both first and second), is put into a tub that has a composition of sand and gravel media with different sizes and thickness variations, where the bottom layer is coarser and the upper part is the smoothest (fine sand).
  
  At the bottom of the tub, a perforated filtrate pipe is planted which will drain the relatively free filtrate / water from the sludge out to the collecting tub. A layer of mud will be left on the sand and dry (cracked) by itself by the hot sun, which is commonly known as a "sludge cake".
  
  In this process, the pouring height of the liquid slurry should be examined by observation, so that the final thickness of the sludge cake is about 5cm above the fine sand layer. Sludge is generally black or brown in color, with a rough and cracked surface.