Views: 8 Author: Ryde Environment Publish Time: 2019-05-17 Origin: Ryde Environment
Nowadays, environmental problems are becoming more and more serious, so sludge dewatering is becoming more and more widely used.
Sludge dewatering is a sludge treatment method that removes water from the raw, concentrated or digested sludge in the fluid state and converts it into a semi-solid or solid mud block.
There are also many kinds of sludge in life, including:
The remaining activated sludge discharged from the secondary sedimentation tank of the domestic sewage plant;
The physicochemical sludge discharged from the sedimentation tank of the waterworks or the concentration tank;
The sludge produced by the industrial wastewater treatment, and the like.
Sludge dewatering is a sludge treatment method that removes the fluid from the native, concentrated or digested sludge and converts it into a semi-solid or solid sludge.
After dewatering, the sludge moisture content can be reduced to between 55 and 80 percent, depending on the nature of the sludge and sediment and the effectiveness of the dewatering equipment.
Further dewatering of the sludge means that the sludge is dried, and the moisture content of the dried sludge is less than 10%.
Natural drying method
This method is generally suitable for use in dry, low-rain, sandy soil areas.
Granulation dehydration method
The water granulation dewatering machine is a new device developed.
Mechanical dehydration method
Usually the sludge is pretreated to improve dewatering performance before dehydration. Mechanical dehydration methods are filtration and centrifugation.
Due to the high water content of the sludge, it is bulky and fluid. After the above process, the sludge volume is reduced to one-tenth of the original, and the liquid is converted into a solid state, which is convenient for transportation and consumption.
The sludge has a high content of organic matter, which is highly prone to spoilage and produces foul odor.
After the treatment in the digestive stage of the above process, some of the easily spoiled organic matter is decomposed and transformed, which is not easy to be spoiled, and the malodor is greatly reduced, which is convenient for transportation and disposal.
Sludge, especially in primary sludge, contains a large number of pathogenic bacteria, parasitic eggs and viruses, which are easy to cause widespread spread of infectious diseases.
Through sludge dewatering most of the aphid eggs, pathogens and viruses can be killed, and the sanitary indicators of the sludge are greatly improved.
Sludge is a resource that contains a lot of heat and its calorific value is between 10,000 and 15,000 kJ/kg (dry mud), higher than coal and coke.
In addition, the sludge is also rich in NPK, which is an organic fertilizer with high fertilizer efficiency.
Through sludge dewatering, the organic matter can be converted into biogas, and the heat can be utilized, and the fertilizer efficiency can be further improved.
Plate and frame sludge dewatering machine
Advantages: low price, good at dehydration of inorganic sludge, low moisture content of mud cake.
Disadvantages: easy to block, need to use high pressure pump, not suitable for dewatering of oily sludge, it is difficult to achieve continuous automatic operation.
Advantages: low prices, widespread use, and relatively mature technology.
Disadvantages: easy to block, need a lot of water to clean, causing secondary pollution.
Centrifugal sludge dewatering machine
Advantages: Large processing capacity.
Disadvantages: high power consumption, high noise, and severe vibration; maintenance is difficult, not suitable for solid-liquid separation with close specific gravity.
1. It can realize continuous dehydration treatment, so the supporting equipment before and after can also be processed continuously, thus eliminating complicated operation control.
2. The structure is simple, the rotation speed is low, and the parts that are driven to rotate are small, so the consumable parts to be replaced are small and the maintenance cost is low.
3. Low speed, low noise, no vibration, can be installed on a simple machine.
4. Low speed, low running power, so the daily running cost is low.
5. It is easy to realize a closed structure, which can easily solve the odor problem and recover the gas generated during the dehydration treatment.
6. The structure is simple, the adjustment and maintenance parts are few, and the daily management operation is simple.
7. The structure is simple, and the comprehensive cost is lower than other types of dehydrators.
The sludge has the characteristics of high water content, a large number of harmful organisms such as pathogens and microorganisms, high content of heavy metals and organic matter, and if it is not treated before discharge, it will cause secondary pollution to the environment.Therefore, sludge dewatering is very important at present. So we hope everyone can pay more attention to sludge dewatering.