Method for removing tar contained in waste denitration catalyst

Abstract

The invention discloses a method for removing tar contained in a waste denitration catalyst and relates to the technical field of resource reutilization. The method includes the steps that vacuum dustsuction is conducted, wherein the catalyst obtained after vacuum dust suction is immersed into diluents of a tar cleaning special cleaning agent; the cleaned catalyst is subjected to spraying cleaning; and the catalyst obtained after spraying cleaning is subjected to washing. The method is designed special for tar in the catalyst, the tar on the waste denitration catalyst can be thoroughly removed, the removing efficiency reaches 98% or above, in addition, the cleaning agent for use is high in seepage force and capable of being easily dissolved in water and used at the normal temperature, ignition is not likely to happen, and explosion cannot happen. The cleaning agent can make direct contact with the skin, basically no harm is generated to the human body, a catalyst base body obtained after cleaning is basically not damaged, the crystal form of a TiO2 carrier is not changed, the catalyst can directly enter a regeneration system, and resource recycling of the SCR catalyst is achieved;and environment-friendly pressure is relieved for the glass industry and the coking industry, and good economic and social benefits are achieved.

Description

technical field [0001] The invention relates to the technical field of resource reuse, in particular to a method for removing tar contained in a spent denitrification catalyst, and the treated catalyst can enter a regeneration system for regeneration and reuse. Background technique [0002] With the increasingly stringent national environmental protection policies, the glass industry and coking industry have successively added SCR denitrification systems to ensure that the NOx emission limit requirements are met. However, in the actual operation process, it was found that the denitration catalyst equipped with the SCR denitration system would be polluted by tar during use. The tar adheres to the surface of the catalyst, blocks the micropores of the catalyst, and leads to the deactivation of the catalyst. [0003] Analysis of the cause of tar pollution is related to the fuel burned in the glass factory and the arrangement of the denitrification system. The main fuels used i...

AI Technical Summary

Problems solved by technology

High-temperature calcination has obvious effects on the removal of tar, but during the heating process, the catalyst will inevitably undergo internal combustion, which not only destroys the denitrification catalyst, makes the catalyst unable to be regenerated and reused, but also causes great danger to production and operation.

In addition, although there are currently some cleaning agents and cleaning methods for spent denitrification catalysts, these methods have strong targeting and only have effects on ash, heavy metals, and basic metal oxides in spent denitrification catalysts (especially are heavy metals and alkaline metal oxides), these cleaning agents and cleaning methods can also take away part of the tar to a certain extent when removing the above substances, but because they are not specially designed for tar, the residual amount of tar in the catalyst after treatment is still Too much, the removal rate of tar is less than 50%, and operations such as calcination to remove tar still need to be added in subsequent steps. The residue of tar will seriously affect the subsequent catalyst regeneration, resulting in a greatly reduced catalyst recovery regeneration rate, wasting a lot of resources, and cause environmental pollution

At the same time, due to the particularity of the catalyst, the method that can be applied to the removal of tar on the surface of steel is not suitable for the removal of tar in the catalyst. The cleaning agent and supporting methods used in it will cause problems such as damage to the catalyst matrix or changes in the crystal form, and This type of cleaning agent is usually highly toxic and will cause serious harm to the staff and the environment.

[0006] Therefore, there is still no feasible technology that can effectively remove the tar on the spent denitrification catalyst, resulting in no denitrification catalyst recycling company willing to accept the spent catalyst containing tar, and the waste denitrification catalyst is managed as a hazardous waste in the country, and long-term storage is not allowed In waste production enterprises, the temporary storage conditions are strict and must comply with the hazardous waste management system, which has become a difficult problem for glass factories and coking industries