Screw dehydrator

After the generation of sludge during the wastewater treatment process, it remains in a liquid state with a large volume that is not easily transportable. In order to reduce the moisture content and achieve minimal sludge moisture, a dewatering process needs to be conducted. This process reduces the overall volume of the sludge and facilitates handling and transportation.

Sludge is an inevitable product of the wastewater treatment process in wastewater treatment plants and sewage systems. Improperly treated and disposed of sludge that is thrown into the environment directly contributes to the secondary pollution of the water body and the atmosphere, and also negatively affects the ecological environment and human activities. This is a serious threat that requires careful handling of sludge treatment.

Three types of sludge are identified in wastewater treatment plants: physicochemical sludge, biochemical sludge, and mixed sludge containing both physicochemical and biochemical components.

This new technology combines spiral pressure with dynamic and static rings to achieve energy-efficient and economical processing. Thanks to the continuous movement of the dynamic and static rings, the cylinder is self-cleaning, and the filter openings remain free from clogging. This eliminates the need for high-pressure washing, resulting in significant savings in industrial water usage (one unit can save up to 13,000 tons of water per year).

The slow movement of the main screw shaft (3-5 rotations per minute) reduces mechanical wear on the equipment and prolongs its lifespan. The power consumption of the main unit is less than 1.1 kWh, and an individual machine can save up to 50,000 kWh per year. This technology is not only efficient but also provides significant energy savings, offering numerous benefits in industrial facilities.

The second generation of the dewatering machine has double the processing capacity compared to the first generation. The ATT PDM 300/3 model can effectively process sludge generated from 10,000 tons of wastewater, which is approximately 120-150 tons of sludge. This improved processing capacity enables more efficient handling of larger quantities of sludge and provides flexibility in addressing various needs of wastewater treatment plants.

This technology allows for the natural balancing of internal pressure in the sludge dewatering section. This achieves more efficient and uniform loading on the dynamic and static rings. Through this balanced pressure adjustment, a longer ring lifespan is achieved. This functionality ensures stable and reliable operation of the dewatering machine, contributing to its longevity and reliability.

The green plan and environmental protection are key aspects of this system. The entire machine is enclosed, allowing for direct observation of the process. The housing is easy to disassemble and assemble, ensuring no wastewater leakage and eliminating the risk of secondary pollution. Additionally, the machine is designed to operate with minimal noise, less than 45 decibels (dB). This results in a pleasant and civilized working environment in the room where sludge processing takes place. This system contributes to a more beautiful environment and enables a comfortable and environmentally conscious operation.

Thanks to the automatic control system, the program can be set to achieve automatic operation without the presence of an operator, allowing for efficient sludge processing even without constant staff supervision. This functionality is particularly useful when dealing with large quantities of sludge, streamlining operations and providing flexibility in managing the dewatering process.

The filtration body consists of static rings and dynamic rings that are connected to each other, and a screw shaft passes through them. Sludge is completely dehydrated through mechanical pressure and filtration as it progresses through the system. subjecting to pressure and compression within the spiral-ring system, which enables the extraction of excess water from the sludge and the achievement of dehydration. The sludge is compressed, while the filtrate is separated and drained from the filter gap through the openings in the static and dynamic rings.

1. The sludge from the sludge tank is transported by means of a pump to the sludge dosing tank. The amount of sludge is regulated by measuring the level in the dosing tank, and the excess sludge is returned back to the sludge tank through the return pipe.
2. The sludge is thoroughly mixed with the coagulant in the coagulation tank using an agitator to form coagulated sludge. The optimal floc diameter is approximately 5 mm.
3. The coagulated sludge is concentrated.
4. The concentrated sludge continues its movement in the direction of rotation of the screw shaft, subjected to complete dehydration under the internal pressure created as a result of the backward pressure
5. Dehydrated sludge is ejected from the space between the pressure plates and the screw body. When expelling the sludge, the plates exert a backward pressure, and the screw body helps to remove the sludge from the filter. Sludge processing capacity and humidity can be adjusted by adjusting screw shaft rotation speed and pressure plate spacing.

1. Sludge created by coagulation precipitation of industrial wastewater
2. Excess activated sludge of industrial wastewater
3. Excess activated sludge from public wastewater treatment plants
4. Sludge from water and fertilizer treatment processes
5. Separation of solids and liquids in the production process of the factory

1. The capacity of the sludge dehydrator should be adjusted within the appropriate range to avoid frequent system oscillations and negative impact on treatment efficiency caused by a sudden increase in load. Sludge flow, flocculant flow and differential speed should be adjusted according to changes in sludge concentration. Flocculant flow and differential velocity increase if sludge flow or sludge concentration increases. Flocculant flow and differential velocity are reduced if the sludge flow or sludge concentration is reduced.
2. The choice of flocculant should be suitable for achieving optimal treatment results with minimal consumption. The type and dosage of flocculants depend on the quality of the agent, the nature of the sludge, the construction of the equipment and the working conditions.
3. Mud performance should be combined with torque data to determine the best range of differential speed values. It is recommended to use a lower differential number in order to achieve better processing results and savings without clogging, while satisfying the processing capacity.
4. The personnel in the field should continuously observe, adjust and harmonize the working parameters in accordance with the changes. Observation and adjustment should be carried out regularly, and the staff should be responsible and attentive in order to achieve the best and relatively stable cooperation of all parameters of working conditions.
5. Check the efficiency of the device regularly. If turbidity of the separating liquid (filtrate) or a decrease in the proportion of solids is noticed, it is necessary to analyze the causes and take concrete measures to solve them.
6. Regularly monitor the effect of sludge dehydration. If a decrease in the proportion of solids is observed, analyze the situation and take appropriate measures.
7. Regularly monitor the operating conditions of the sludge dehydrator and take corrective measures in case of emergency situations to ensure normal operation.
8. Allow enough time to rinse the dehydrator daily. The device is difficult to clean after the sludge has completely dried.
9. Regularly observe, inspect and maintain the machine according to the requirements and instructions of the sludge dehydrator.
10. Pay attention to the wear of the dehydrator and replace it when necessary.