How to Use Rotary Kiln Incinerator for Sludge Treatment?

Sludge is a common solid waste in daily life, which is commonly found in sewer pipe networks and sewage treatment plants. The amount of sludge waste produced in the industry is huge each year, among which electroplating sludge, leather sludge, pickling sludge, oily sludge, sewage sludge, and other types of sludge discharge are increasing day by day.

Electroplating sludge
Electroplating sludge
Pickling sludge
Pickling sludge
Oily sludge
Oily sludge
Sewage sludge
Sewage sludge

Why is Sludge Treatment Necessary?

The sludge waste contains a lot of harmful substances, including heavy metals, bacteria, pathogens, etc. If it is not treated, it will inevitably have a greater impact on the environment and human health. Sludge treatment came into being under such circumstances. Sludge treatment is the reduction, stabilization, and harmless processing of various types of sludge such as concentration, conditioning, dehydration, stabilization, drying, or incineration.

There are roughly four methods for sludge treatment in the world, namely reclamation, landfill, incineration, and land use. Most landfills are open-air sites. After the rain, a large amount of sludge containing oil that is difficult to degrade organic matter, heavy metals, and pathogenic microorganisms will corrode and penetrate the land, posing safety hazards to the soil, and causing new pollution to the surrounding environment of the city. In Europe, the treatment of sludge through sludge incineration has become a very important way. Due to stricter restrictions on sludge accumulation, incineration of sludge may become the only way to treat sludge.

Sludge Waste Rotary Kiln Incinerator

Sludge rotary kiln treatment process flow
Sludge rotary kiln treatment process flow

The sludge incineration process needs to be carried out in a sludge rotary kiln. Sludge waste rotary kiln is a kind of hazardous waste rotary kiln incinerator, which is specially used to treat sludge waste. It is a rotary kiln calcining equipment integrating drying, heating, and calcination. During the sludge incineration process, all germs and pathogens are completely killed by the high temperature in the sludge rotary kiln, and the toxic and harmful organic residues are decomposed by thermal oxidation. The sludge is incinerated through the sludge rotary kiln to achieve the greatest reduction in volume, and the final product incineration ash is obtained. Incineration ash can be used as a raw material for cement production to fix heavy metals in the concrete to prevent them from re-entering the environment.

Dimension(m)Rotate speed(r/min)Slope(%)Capacity(t/h)Speed ratioPower(kw)catch wheelSupport numberWeight(t)
Specification parameters of rotary kiln incinerator

Performance Advantages of Sludge Rotary Kiln

1. Organic matter decomposes thoroughly

The internal temperature in the sludge rotary kiln incinerator is generally between 1350℃-1650℃, or even higher. The materials in the kiln are in a highly turbulent fluidization state during the incineration of sludge. Therefore, the harmful organic matter in the sludge in the kiln can be fully burned, and the incineration rate can reach 99.999%. Even stable organic matter such as dioxins can be completely decomposed.

2. Inhibit the formation of dioxin

Since the feeding point of the dried sludge is in a decomposition furnace higher than 850°C, the furnace has a large heat capacity and a stable temperature, which effectively inhibits the formation of dioxin precursors. The practice of disposing of toxic and hazardous wastes in cement kilns at home and abroad shows that the concentration of dioxin emissions produced by waste incineration is far below the emission limit.

Sludge incineration in rotary kiln
Sludge incineration in rotary kiln

3. No fly ash is produced

The waste gas and dust discharged from calcination are collected by the bag filter at the end of the kiln as cement raw materials and then enter the kiln for calcination. No hazardous waste fly ash is generated.

4. Solidified heavy metal

The refractory bricks, raw materials, kiln skin, and clinker in the sludge waste rotary kiln are all alkaline, which can absorb SO2, thereby inhibiting its emission. In the process of cement firing, the heavy metals in the sludge and slag can be fixed in the structure of the cement clinker. So as to achieve the role of being cured.

5. High efficiency of resource utilization

Through the treatment of the rotary kiln incinerator, the organic and inorganic components in the sludge can be fully utilized, and the resource utilization efficiency is high. The sludge contains some organic matter (above 55%) and combustible components, which will generate heat when calcined in the rotary kiln. The low calorific value of sludge is about 11MJ/kg, which is equivalent to lean coal in the sense of calorific value. Lean coal contains 55% ash and 10%-15% volatile matter and has a calorific value of 10-12.5MJ/kg.

The sludge rotary kiln incinerator has higher treatment efficiency, the incineration products can be used as cement raw materials, and the heat produced by incineration can be used for power generation, with significant economic benefits. It has become the first choice of incineration equipment for many sewage treatment plants and industrial solid waste treatment enterprises. As a high-quality rotary kiln supplier, AGICO welcomes you to send inquiries for details at any time.