What sludge treatment equipment will be used in municipal wastewater plants?

There are many types of equipment used in this process, such as valves, filtration systems, presses, etc.

You can look for it in these brands such as Paiwo, Jieying, Changqing, Saibang, and Kinder.

Fertilizer utilization, raw materials for building materials.

In terms of final sludge disposal, the only effective ones are landfill, incineration, fertilizer utilization, and building material raw materials.

From the perspective of resources, the first consideration is the utilization of materials, then composting; Then the consideration is the utilization of energy, then it is drying + incineration; The unusable option is landfill, which also takes up land resources.

In addition to being used as a raw material for landscaping and organic fertilizer, some places use sludge and other municipal wastes as raw materials for anaerobic digestion to make biogas, purification and compression and vehicle gas. In other places, the composite raw materials of municipal sludge and kitchen waste are anaerobically digested, which not only eliminates the garbage, but also uses the sludge.

Sludge disposal dilemma.

Sludge is a kind of biosolid material produced in the sewage treatment process that is prone to spoilage and odor. It enriches the pollutants in the sewage, contains a large number of nutrients such as nitrogen and phosphorus, organic matter, viruses and microorganisms, parasite eggs, heavy metals and other toxic and harmful substances, and will cause serious harm to the environment if not effectively treated and disposed of.

According to the China Sludge Treatment and Disposal Market Analysis Report (2013), by the end of the third quarter of last year, more than 3,500 urban sewage treatment plants had been built in China. For every 10,000 tonnes of sewage, about 5 to 10 tonnes of sludge are produced. Next year, the production of wet sludge (moisture content of 80) in urban sewage treatment plants will reach 33.59 million tons, that is, 920,000 tons of sludge per day.

Chen Tongbin, a researcher at the Institute of Geographic Sciences and Natural Resources Research of the Chinese Academy of Sciences, revealed that the effective disposal rate of urban sludge is less than 20, and the safe disposal of urban sludge has become a bottleneck restricting the healthy development of the sewage industry.

The above content reference: People's Daily Online-China explores to solve the sludge treatment dilemma.

At present, most municipal sewage treatment plants use the activated sludge method to remove sludge.

The principle of biological treatment is to complete the decomposition of organic matter and the synthesis of organisms through biological action, especially the action of microorganisms, and transform organic pollutants into harmless gas products (CO2), liquid products (water) and solid products rich in organic matter (microbial community or biological sludge); The excess biological sludge is separated from the purified sewage by the solid-liquid separation in the sedimentation tank and removed from the purified wastewater.

Continuous dehydrator with filtration.

The continuous dewatering machine with filtration used in sewage treatment plants is about the same as the continuous dewatering machine with filtration used in water treatment plants.

The continuous dewatering machine with filtration is suitable for the dewatering of various mixed sludge, treating typical digested mixed sludge with a solid content of 5%, and when the solid load of the filter cloth is long, a dewatered sludge cake with a solid content of 19% can be obtained.

Generally speaking, the dewatering effect of a continuous dewatering machine with filtration for different sludges is comparable to that of using a vacuum dehydrator. Compared with the use of vacuum dehydrators, continuous dehydrators with filtration are less prone to the problem of sludge adhesion to the filter cloth, and their power consumption is lower.

Sludge treatment and final sludge disposal: mainly including thickening, digestion, dewatering, composting or domestic landfill. Concentration can be mechanical concentration or gravity concentration, and subsequent digestion is usually anaerobic medium temperature digestion, that is, anaerobic technology.

The biogas produced by digestion can be used as an energy source for combustion or power generation, or for chemical products, etc. The sludge produced by digestion is stable in nature, has fertilizer effect, and after dehydration, reduces the volume and forms cakes, which is conducive to transportation. To further improve the hygienic quality of the sludge, the sludge can also be hand-composted or mechanically composted.

Composted sludge is a good soil amendment. Sludge with excessive heavy metal content should be disposed of carefully after dehydration, and it is generally necessary to landfill and seal it.

No, but it can be used to produce organic fertilizer for crops.

It can be used to raise earthworms, and then use earthworms to make feed.

Basically, no, the composition of municipal sewage is too complex, and the sludge is very crispy after dewatering. If you have to make bricks, the cost is not low. However, there is also a type of sludge called "activated sludge" that flows back into the sedimentation tank to participate in biodegradation.

Dry incineration, compound fertilizer production, sanitary landfill. 1. Drying and incineration: sludge drying can control the moisture content of sludge at 10 40, reduce the volume and weight of sludge, reduce transportation costs and landfill costs, and greatly reduce the odor of sludge.

The drying plant can be divided into direct drying and indirect drying, and its energy consumption is related to sludge composition and moisture. Vertical drying device is generally recommended for indirect drying, and fluidized bed technology is selected. <

Dry incineration, compound fertilizer production, sanitary landfill.

1. Drying and incineration: sludge drying can control the moisture content of sludge at 10 40, reduce the volume and weight of sludge, reduce transportation costs and landfill costs, and greatly reduce the odor of sludge. The drying plant can be divided into direct drying and indirect drying, and its energy consumption is related to sludge composition and moisture.

Indirect drying (the use of biogas through a heat exchanger) is generally recommended with a vertical drying unit and a fluidized bed process. In the tandem process of drying and incineration, the degree of drying depends on the calorific value of the sludge and the thermal energy of the incinerator, so that the energy of drying is balanced as much as possible, and no additional fuel is added.

2. Compound fertilizer: According to the current economic conditions in China, for most sewage plants, sludge is a more feasible and realistic solution for farmland. Nitrogen, phosphorus, potassium and trace elements in sludge have a role in increasing crop yield; The organic matter and humus in the sludge are good soil amendments.

Sludge is properly thickened, dewatered and transported to the suburbs or neighbouring provinces for use as fertiliser, which is the method used by many sewage treatment plants. However, farmland fertilization is seasonal, and when mud fertilizer is not needed, the sewage plant will be full of mud, affecting normal operation. As a result, some sewage plants pay farmers to pull the sludge away without asking where it goes, which causes secondary pollution.

3. Sanitary landfill: Sludge sanitary landfill originated in the 60s of the last century, which is based on the traditional landfill from the perspective of environmental protection, after scientific site selection and necessary site protection treatment, it requires a strict management system and scientific engineering operation methods. At present, it is a relatively mature sludge disposal technology.

The basic method is that the municipal sludge is simply sterilized and dumped directly into the lowlands or valleys to create artificial plains. It has low requirements for sludge treatment technology in the early stage, and digestion and volume reduction can be carried out generally. If it is not digested, it can also be allowed to dry naturally.

Therefore, it requires a large area of site and a large amount of transportation costs, and the foundation needs to be treated with anti-seepage treatment to avoid polluting groundwater, so the proportion of sludge landfill disposal has been getting smaller and smaller in recent years. However, landfilling does not ultimately avoid environmental pollution, but only delays the time it takes to produce.