Method for recycling organic matters of paste and slurry-shaped waste by a multi-hearth furnace coupling gas stripping pyrolysis method

Abstract

The invention relates to a method for recycling organic matters of paste and slurry-shaped waste by a multi-hearth furnace coupling gas stripping pyrolysis method, and belongs to the technical field of waste pyrolysis. According to the method, consumption is low, the processing mode is simple and the processing effect is good. The method for recycling the organic matters of the paste and slurry-shaped waste by the multi-hearth furnace coupling gas stripping pyrolysis method comprises the following steps that 1, the paste and slurry-shaped waste is put into a homogenizing tank to be homogenized; 2, the homogenized paste and slurry-shaped waste is conveyed into a feeding machine by a mud cake conveying pump; and 3, the homogenized paste and slurry-shaped waste is conveyed into a multi-hearthpyrolysis treatment system to be treated through the feeding machine, and an organic matter recovery device is used for collecting the low-boiling-point organic matters.

Description

technical field [0001] The invention belongs to the technical field of waste pyrolysis, and in particular relates to a method for recovering the organic matter of slurry waste through the pyrolysis method of a multi-hearth furnace coupling gas stripping process. Background technique [0002] In the crude oil storage and transportation station set up in the oil field, the tank bottom sludge that is regularly cleaned out from the oil storage tank is a representative type of paste or slurry waste that contains high concentration and low boiling point organic matter and has high recycling value. , the organic composition of which is similar to that of crude oil, which can be recovered and used as raw material oil for refineries. [0003] In addition, for local soil or surface water pollution caused by various accidental leakage accidents, if the pollutants have a wide distillation range but are mainly composed of low-boiling organic matter (representative substances include: coa...

AI Technical Summary

Problems solved by technology

This conventional design is suitable for the pyrolysis treatment of wastes such as waste water sludge, waste tires, and scrapped printed circuit boards. It is just in the concentrated distillation area of ​​low-boiling organic matter, so the pasty waste has enough time to transform into a viscous phase due to slow heating, and gradually forms on the surface of the rake teeth (bare metal parts, which belong to the "hot area" in the drying area) Agglomeration of slagging, and further adhesion of new viscous material, so that the gap between the rake teeth is completely filled with material and loses the function of stirring and pushing the material to move on the hearth. The tines "climb" above the rake arms and form a hard slagging "shell" that completely disables the moving parts of the furnace, causing downtime

[0013] A simple solution to increase the furnace temperature in the drying area by adding fuel to the first or second furnace has been taken, but due to the local extreme high temperature caused by the flame of the burner in the furnace, the recovery rate of organic matter is significantly reduced (occurrence complex reaction processes such as high-temperature polymerization, cracking, partial oxidation, and nitration, which increase the yield of non-condensable gases and reduce the yield of organic matter recovered by condensation), and the hard slagging blocks formed near the nozzle of the burner will quickly Causing the combustion unit to shut down

[0014] Attempts were also made to install a double-layer steel cooling plate with a labyrinth channel on the upper hearth, using heat transfer oil, high-temperature flue gas from a single incinerator, and high-temperature hot air from a single hot blast stove as heat sources to improve the operation of the drying area Although the temperature can alleviate the formation speed of the viscous phase to a certain extent, due to the sharp increase in the area of ​​the "hot zone", and the heat resistance of the steel and the heat exchange efficiency of the components restrict the allowable upper limit of the furnace temperature (the maximum temperature in the drying zone can be maintained at about 280°C), and the high-temperature corrosion of the material on the steel is greatly accelerated (there are potential safety hazards in production), resulting in unsatisfactory application results

[0015] It has also been attempted to introduce the high-temperature flue gas produced by a separate coal-fired or oil-fired incinerator, or to introduce the pyrolysis tail gas (containing a certain concentration of combustible gas components) of a multi-hearth furnace after recovering organic matter into a post-type post-combustion chamber for complete incineration. The high-temperature flue gas is directly diverted to the drying area of ​​the multi-hearth furnace as a heating medium, but due to the high heat dissipation of the pipeline, the high-temperature flue gas conveying device is difficult to operate without failure for a long time, and the flue gas dust seriously affects the quality and application performance of the recovered organic matter. Problems such as impact, investment and operating costs have risen sharply, and are not accepted by users

[0016] (2) The problem of excessive energy consumption of the overall pyrolysis device

[0021] If no process air is fed into the pyrolysis functional area of ​​the multi-hearth furnace for special paste / slurry waste, or the amount of process air introduced is much smaller than the chemical reaction formula volume ratio (for example: ≤25% formula volume ratio air consumption), then In the pyrolysis reaction zone, only the gasification and cracking reactions of organic matter in the solid phase composition can occur. These two reactions are endothermic reaction processes, which are the main reasons why the overall energy consumption of the furnace exceeds expectations.

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