Sludge thickening with Klein belt thickener type BGT

Process description:

Advantages of the belt thickener type BGT

• robust and compact stainless steel design
  
• little space requirement
  
• low investment and operation costs
  
• reliable and safe process, little maintenance requirements
  
• low water consumption, use of filtrate for belt cleaning
  
• lower-wear and low-noise operation
  
• continuous and fully-automatic operation
  
• high filtrate quality and low polymer consumption
  
• careful thickening without sludge restacking
  
• high volume reduction of the sludge for:
  
  - an optimal operation of the digestion tower
  - a reduction of transport costs for sludge disposal

 

Sludge conditioning

The sludge to be thickened is delivered to the belt thickener by means of an infinitely adjustable sludge feeding pump (eccentric screw pump), which is working without blockage due to its special design and operation mode.

The sludge flows through a mixer with a dosing device for a polymer solution (0,1 % concentration). The solution is added tangentially and is mixed with the sludge. The generated sludge flakes stabilize in the pipe and reach the feeding range of the belt thickener in an optimal dewatering condition.

Sludge Thickening

The sludge flakes settle very smoothly on the sieve belt of the belt thickener. Here a major part of the water is separated and is drained off through the sieve belt into the filtrate tank.

In order to reach an optimal prethickening, the sieve belt is equipped with ploughs which tear open the sludge cake and ensure an optimal water separation.

The thickened sludge layer is discharged into a sludge tank at the end of the sieve belt. The pump for thickened sludge is regulated by a level control.

The separated filtrate is collected in an integrated tank and can be used for cleaning of the sieve belt.

Cleaning is performed by means of spray bars which can be cleaned with special internal cleaning brushes during operation.

By the special twin-section design of the filtrate tank, the impurified water from sieve belt cleaning can be collected separately from the filtrate.

Excess filtrate as well as the dirty water flow back into the sewage treatment plant.

Design

The compact and space-saving machine design ensures maximum thickening efficiency on minimum space.

The belt thickener mainly consists of a stainless steel frame with one drive roller and one tension roller for the sieve belt. The sieve belt is designed with a forced belt guiding mechanism, which ensures a centric run of the belt.

The plant is operated by a control unit which indicates the particular operation mode by means of signal lamps.

Faults are indicated by an acoustic and visible signal and cause an automatic shut-down of the plant.

In automatic operation mode it is possible to run the plant in continuous operation without supervision.

The plant should be cleaned once a week by spray washing. Together with the recommended lubrication cleansing takes approx. 1 hour.

Our delivery scope comprises the engineering, delivery, assembly and commissioning of complete plants incl. the necessary accessories, polymer preparation system and fully-automatic control.