How to choose a sludge dewatering machine
The sewage will produce a large amount of sludge after sedimentation treatment. Even if it is concentrated and digested, the water content is still as high as 96%. The volume is very large and difficult to absorb and dispose. It must be dehydrated to increase the solid content of the mud cake to reduce the pollution. The area of mud stacking.
Generally, large and medium-sized sewage treatment plants use mechanical dehydration. There are many types of dehydration machines, which can be divided into three categories: vacuum filtration dehydration, press filtration dehydration and centrifugal dehydration according to the dehydration principle. Regarding the working principles of filter presses (including belt filter presses and plate-and-frame filter presses) and centrifugal dewatering machines that are often used in domestic sewage treatment plants, key issues to be considered when selecting equipment, and maintenance and operation costs, etc. One introduction.
1. The belt filter press is less affected by sludge load fluctuations, and has the characteristics of low sludge water content, stable work and low consumption, relatively simple management and control, and low requirements for the quality of operating personnel. At the same time, because the belt filter press dehydrator entered the country earlier, a considerable number of manufacturers can produce this equipment. When making decisions on construction of sewage treatment projects, belt filter presses can be used to reduce project investment. Most of the newly built sewage treatment plants in China use belt filter press dehydrators. For example, the five dehydrators in the first phase of the Beijing Gaobeidian Sewage Treatment Plant are all belt filter press dehydrators. The filter belts and roller press cylinders have been in good condition since they were put into operation. , So this model was still used in the second phase equipment selection.
2. Compared with other types of dewatering machines, the general plate and frame filter press has the highest solid content rate of mud cake, which can reach 35%. If considering the factors of reducing the land occupation of sludge stacking, the plate and frame filter press should be the first choice Program. How the filter plate moves. The requirements can be completed automatically or semi-automatically by a hydraulic-pneumatic device, which is inconvenient to operate. The filter cloth oscillating device can make the filter cake easy to fall off. Compared with other types of dehydrators, the biggest disadvantage of the plate-and-frame filter press is that it occupies a large area. Take the belt filter press used in the first phase of the Beijing Gaobeidian Sewage Treatment Plant and the plate and frame filter press used in the Anshan Industrial Sewage Treatment Plant as an example for comparison: the Gaobeidian Sewage Treatment Plant has a sewage treatment capacity of 500,000 t/ d. The sludge output is 1852. 5m3/d and the dry matter is 92.63t/d. Five German KLEIN-KS30 belt filter presses are used. The basic area of each filter press is only 2750*3500mm, Anshan The sewage treatment plant has a water treatment capacity of 22t/d and a dry matter of 275t/d. Six plate and frame filter presses are used. Each filter press covers an area of 2400*12000mm. At the same time, because the plate and frame filter presses are Intermittent operation, low efficiency, poor operating room environment, secondary pollution, domestic large-scale sewage treatment and measurement plants have been rarely used.
Use of sludge dewatering machine
The sludge dewatering machine has the advantages of small size, good effect, low energy consumption, low noise, no vibration, high degree of automation, convenient centralized management, and convenient maintenance. Mainly used:
1. Industrial wastewater coagulation sedimentation sludge
2. Industrial wastewater excess activated sludge
3. Urban sewage treatment surplus sludge
4. Community sewage sludge
5. Adding chemicals to agglomerate sludge in water purification plant
6. Water and fertilizer treatment surplus sludge
7. Solid-liquid separation in the factory manufacturing process
Analyze the deviation of the mesh belt
The sludge dewatering machine is a continuous operation of sludge treatment equipment. Because of the low water content of the sludge, it has stable operation, low energy consumption, relatively simple control and management, and convenient maintenance. It has been used in the industry, mining, and sewage treatment industries. Wide range of applications. The following introduces a common problem and solution in the use of sludge dewatering machine. In the production and operation of the belt dewatering machine, there are many factors that affect the uniform force of the mesh belt, and the phenomenon of deviation and discount of the mesh belt is prone to occur. Once the mesh belt has creases, the creases will frequently rub against the sludge scraper. Excessive wear and tear occurs, resulting in a greatly shortened life of the mesh belt and causing greater economic losses for the enterprise.
Operation and management principles of sludge dewatering machine
1. The processing capacity of the sludge dewatering machine is controlled within an appropriate range, and the sludge flow rate, flocculant flow rate and difference are adjusted to avoid frequent system fluctuations and affect the treatment effect due to sudden increase in load caused by equipment overload. Achieve greater equipment processing efficiency.
2. When the sludge concentration changes, it is necessary to adjust the flocculant flow rate and differential speed in time to ensure the treatment effect and avoid waste; if the sludge flow increases or the sludge concentration increases, the flocculant flow tracking increases, and the differential speed increases accordingly; When the sludge flow decreases or the sludge concentration decreases, the flocculant flow tracking decreases, and the differential speed decreases accordingly.
3. There is no best flocculant, only the most suitable. The type and consumption of flocculant depend not only on the match between the quality of the agent and the nature of the sludge, but also on the match with the equipment structure and operating conditions. Only the three get the best The best operation combination can achieve the best treatment effect and the highest treatment efficiency under the condition of the lowest flocculant consumption.
4. The performance of mud biscuits should be combined with torque data to determine the best differential speed value range. In principle, try to use a lower differential number to achieve better processing effects and save flocculation without causing clogging of the centrifuge and meeting the processing capacity. Agent consumption.
5. The work that all on-site management and operators have to do is to continuously observe, adjust in time and be good at summarizing, as far as possible, seeking the best and relatively stable perfect cooperation of all working condition parameters in the various changes that may occur. Under normal circumstances, this kind of observation and adjustment should be carried out every 1 to 2 hours. It is necessary to strictly avoid the situation that the equipment operating condition parameters are maintained for a long time or one shift without any adjustment after the start of the machine. The on-site operators Laziness or weak sense of responsibility is one of the main reasons for the long-term low operating efficiency of the sludge dewatering workshop, large fluctuations in the treatment effect, and waste of medicine consumption.
6. Check the dewatering effect of the dewatering machine frequently. If the separation liquid (or filtrate) is found to be turbid and the solids turning back rate decreases, the reasons should be analyzed in time, and specific measures should be taken to solve them.
7. Frequently observe the effect of sludge dewatering. If the solid content of the sludge cake decreases, analyze the situation and take measures to solve it.
8. Frequently observe the operating conditions of the sludge dewatering device, and take corrective measures for abnormal phenomena to ensure normal operation.
9. Enough flushing time of the dehydrator should be ensured every day. When the dehydrator listens to the machine, rinse the inside and the whole body thoroughly to ensure cleanliness and reduce odor. Otherwise, it is very difficult to rinse after the mud is dry.
10. According to the requirements of the dewatering machine, perform frequent observation and inspection and maintenance of the machine.
11. Always pay attention to check the wear and tear of the dehydrator, and replace it if necessary.
12. Timely discover the damage to the filter belt caused by the sand particles in the mud in the dewatering machine, and replace it in time if the damage is serious.
13. Make an analysis and measurement record.