Sludge pyrolysis and gasification technology, is the municipal sludge through the frame dehydration filter or low temperature drying process, the calorific value reached more than 2800kcal/kg (if lack of calorific value is added into 10% of pulverized coal), and then into the gasification furnace, after drying, pyrolysis, carbonization and so on a series of reactions to its full pyrolysis and gasification, in the pyrolysis and gasification of organic macromolecular lytic state into small molecule combustible gas, residue for molten slags and all kinds of pathogenic bacteria were completely kill the process.
The patented process is characterized by inhibiting the production of toxic and harmful gases. Sludge after the company unique characteristics of craft processing, continuous access to the whole process of pyrolysis and gasification furnace can be used 24 hours a day, uninterrupted operation, stable production and gas produced can be used for heating, power generation, gasification inorganic compounds, preparation of construction materials. Save a lot of coal, oil, natural gas, a one-time energy, the full realization of the sludge as a resource, utilization, the saved time equivalent energy carbon emissions, in the international market for carbon trading, get a good income.
Sludge pyrolysis and gasification technology is refers to the municipal sludge through special processing into the gasification furnace, through drying, pyrolysis and carbonization of a series of reaction, so as to make them fully pyrolysis and gasification, in pyrolysis and gasification of organic macromolecular lytic state into small molecule combustible gas, remnants of molten slag, all kinds of bacterial pathogens were completely kill the process.
Sludge is the product of sewage treatment, is a composed of organic debris, bacteria, inorganic particles, colloid extremely complex non plastids. The average total organic matter of municipal dry sludge was 68.7%. Calorific value of dry basis sludge: 2600-2800kcal/kg sludge.
The calorific value of the furnace fuel is the basis of the design of the incinerator. The heating value determines the whole thermal state, such as the heat capacity, the burning temperature, the amount of air, the amount of gas, steam and so on.
Water content of 60% sludge, after drying treatment, most of the water evaporation, water content fell to 20%, the calorific value increased significantly. The calorific value of sludge is about 2000 kcal/kg.
Two, the gasification and pyrolysis process
Drying section (80-120 C)
Carbonization stage (450- C)
Pyrolysis and gasification section (1100-1200 C)
– the combustion section (generating CO2 and inorganic slag)
Wet ash removal section (quick cooling)
Three, process characteristics
(1) to effectively curb the generation of dioxin like substances.
(2) a short time completely harmless sludge only after 30 minutes of the dry distillation gasification pyrolysis treatment, 100% to kill harmful bacteria can be accomplished completely remove the odor.
(3) resource effect best: carbonization and pyrolysis gasification gas used directly for power station boiler heating alone, brick, industrial used commodity gas, residents gas, can do for automobile gas
(4) heat utilization rate is high: the pyrolysis a pyrolysis gasification technology of power plant heat utilization rate is as high as more than 70%, can greatly save energy and resources.
(5) significant reduction, low operating costs
(6) processing technology can achieve large-scale continuous production, and realize the whole closed, does not affect the surrounding environment and process systems and equipment to adapt to the strong.
The difference between sludge incineration treatment technology and pyrolysis gasification technology
The above two kinds of sludge treatment processes are required to carry out the pretreatment of sludge raw materials including drying steps, remove the moisture content in the sludge. When the sludge is burned by a fluidized bed furnace, semi dried sludge can be added. Pyrolysis and gasification process and incineration process had obvious differences in by-product utilization and processing technology: slag block is the pyrolysis and gasification device major solid by-product, is directly related to the content of mineral components in the yield and raw sludge; incineration treatment device of solid byproduct is generally used as landfill cover soil, but toxicity as described in the previous section, sludge incineration process of ash has begun to caused increasing attention.
According to the difference of the two kinds of technology, it can obviously get the contrast information of its advantages and disadvantages. Table 6 gives a detailed comparison of the advantages and disadvantages of the two techniques.
Comparison of advantages and disadvantages of incineration treatment technology and pyrolysis gasification technology
“Cut the weight and volume of the sludge”, and in “does not need to occupy the land for landfill final product processing”, the two kinds of technology has the same advantages; but due to the extensive use of synthetic gas, and pyrolysis of treatment technology can produce a large number of synthetic gas products, which makes this technology very attractive. Compared with the pyrolysis and gasification technology, the disadvantage of incineration technology is that the cost of the gas phase is very high. Pyrolysis and gasification technology of another significant advantage is that it not only can meet the requirements of existing pollutant emission standards, and may also meet the future will be the introduction of new, more stringent standards for the discharge of pollutants; in contrast, incineration treatment technology may need more investment in order to meet the requirements of the future, more stringent emission regulations.
Although pyrolysis and gasification technology already does not belong to the type of new technology, but the incineration treatment technology familiar has quite a long history of the, (compared with, pyrolysis and gasification technology for sludge treatment process is a newly developed technology category). Had a few scholars of sludge pyrolysis and gasification process of Professional Studies (Fytili and Zabaniotou, 2006), but in order to obtain the ideal, can be used for gas generation and / or other uses of synthetic gas products, still need of sludge pyrolysis and gasification technology for more basic research. There have been several references to the wastewater