Sludge belt thickening filter press

1. Sludge belt thickening filter press

Sludge belt thickening filter press is a sludge dewatering equipment widely used in sewage treatment and other fields. It integrates the functions of sludge thickening and filtration, and has many excellent characteristics.

(I) Scope of application

Municipal field: The dewatering treatment of sludge generated by urban domestic sewage has a significant effect, which can effectively reduce the water content of sludge and facilitate subsequent treatment and disposal, such as landfill, incineration, etc.

Industrial field

Metallurgical industry: Treat various types of sludge generated in the metallurgical process, such as sludge containing metal impurities generated in ironmaking and steelmaking.

Chemical industry: Suitable for dewatering sludge containing various chemical substances generated in chemical production, such as sludge with complex components such as acid, alkali, and organic matter.

Papermaking industry: It can treat a large amount of sludge generated in the papermaking process, including sludge generated in pulping, papermaking and other processes, and help papermaking companies solve sludge treatment problems.

Printing and dyeing industry: Dewatering the sludge after the treatment of printing and dyeing wastewater. Printing and dyeing sludge usually contains a large amount of dyes, additives, etc. This equipment can effectively remove the water in it.

(II) Working principle

Pretreatment stage

Using the gravity sedimentation concentration method, the volume of the original slurry is reduced and the concentration is increased to form a preliminary concentrated sludge. Then the concentrated sludge is mixed with a polymer flocculant. Under the action of the flocculant, the fine particles are condensed into flocs and initially precipitated into sludge, preparing for the subsequent dehydration operation.

Gravity dehydration

The sludge after flocculation pretreatment is sent to the filter belt of the belt filter press. With the help of the gravity of the sludge itself, the free water outside the flocs is filtered out from the filter belt, thereby reducing the water content of the sludge.

Wedge pre-pressing dehydration

The sludge after gravity sludge dehydration enters the wedge section for pre-pressing dehydration. In the wedge section, the sludge is squeezed and its fluidity is almost completely lost, so that the sludge will not be squeezed out in the subsequent belt filter press dehydration section under normal circumstances.

Roller dehydration

The sludge is repeatedly squeezed and sheared by multiple rollers with reasonable layout in the belt filter press, removing a large amount of capillary water, so that the sludge water content gradually decreases. After that, it is squeezed with a fine pressing roller to finally form a block mud cake with very little water content.

2. Structural composition of sludge belt thickening filter press

Sludge mixing and feeding device

It consists of a sludge mixer or static mixer and a feeding hopper. After the material and flocculant are fully mixed and reacted in the mixer, they flow to the feeding hopper, and the feeding hopper then spreads the material on the filter belt.

Tensioning device

It is generally composed of upper and lower tensioning rollers, tensioning cylinders, pressure regulating gauge valves, etc. For example, in some equipment, the filter belt tension can be adjusted within the range of 50-78N/cm, and the tension of the upper and lower filter belts can be adjusted separately, which can ensure that the filter belt works under appropriate tension and ensure the filtering effect.

Transmission device

The filter belt transmission mostly adopts a stepless reducer, which can be manually controlled and adjusted. The filter belt travel speed is usually 0.8-8m/min, and the normal speed is 2.0-3.0m/min. This speed regulation method can be flexibly adjusted according to the actual sludge treatment volume and treatment requirements.

Deviation adjustment device

It consists of deviation adjustment rollers and correction cylinders, pressure regulating gauges, valves and filter belt correction machine control valves. Its function is to correct the deviation of the filter belt in time to ensure the normal operation of the equipment.

Filter pressing device

It consists of upper and lower filter belts, gravity sludge dewatering section, wedge-shaped pressing section, S-shaped pressing section, etc. These parts work together to gradually realize the dewatering process of sludge, from gravity dewatering to wedge pre-pressure dewatering, and then to the final squeezing dewatering, so as to improve the dewatering efficiency and effect of sludge.

Flushing device

It consists of nozzles, drainage box water retaining rubber plates, etc. When the flushing water pump is turned on, the filter belt can be continuously flushed to prevent the filter belt from being blocked and ensure the filtering performance of the filter belt. However, when the nozzle is blocked by suspended matter and dirt in the water, the dirt on the nozzle needs to be removed in time.

Unloading device

It consists of a knife holder, a scraper plate, a unloading roller, a tension spring, etc. After the sludge is squeezed into a mud cake, the unloading device can scrape the mud cake off the filter belt to complete the entire sludge dewatering process.

Frame

It is welded from various steel sections and painted with anti-corrosion paint. The frame provides a supporting structure for the entire equipment to ensure the stability of the equipment. The application of anti-corrosion paint can extend the service life of the frame and prevent rust and corrosion.

3. Characteristics of sludge belt thickening filter press

Efficient sludge dewatering performance

It has a unique multi-stage sludge dewatering design, which can operate continuously, with low speed but high efficiency. After the sludge has gone through multiple dewatering stages, the moisture content of the mud cake can reach 75% - 70%, achieving a good sludge dewatering effect, effectively reducing the volume and weight of the sludge, and facilitating subsequent processing and transportation.

Good automation performance

It is equipped with a fully automatic anti-deviation belt device and a pressure increase and decrease device. For example, the automatic deviation adjustment device can correct the deviation of the filter belt in time to ensure the stable operation of the equipment; some equipment also adopts pneumatic deviation correction, and is equipped with an alarm and emergency shutdown system, which improves the safety and reliability of equipment operation, is easy to operate, and reduces the intensity and difficulty of manual operation.

Compact structural design

It integrates the functions of concentration, filtration and dewatering, with small size, light weight and small footprint. Compared with other types of sludge dewatering equipment, it requires less installation space at the same processing capacity, and is suitable for sewage treatment plants or sludge treatment sites of various sizes.

Energy saving and low consumption

The power consumption is low during operation, which reduces the operating cost of sludge treatment. At the same time, the water consumption of the equipment for flushing is also within a reasonable range, avoiding the waste of water resources.

Selection of high-quality materials

The pressing rollers and guide rollers are mostly made of stainless steel, which has corrosion resistance and can operate stably for a long time in harsh working environments, extending the service life of the equipment and reducing the frequency of equipment maintenance and replacement.