Method for recovering vanadium, tungstate/molybdenum and titanium elements from waste SCR denitrification catalyst

Abstract

The invention belongs to the field of nonferrous metal recovery, and relates to a method for recovering vanadium, tungsten / molybdenum and titanium elements from a waste SCR denitrification catalyst. The method for recovering the vanadium tungsten / molybdenum and titanium elements comprises the steps of waste catalyst pretreatment, element separation, element purification and element recovery, through a specific recovery process, high-efficiency recovery of vanadium, tungstate / molybdenum and titanium elements in the waste SCR denitrification catalyst is realized (chemical properties of tungstenand molybdenum are very similar, and the process has the same effect on tungsten and molybdenum). The recovery process has the advantages of high recovery rate, excellent product purity, easy operation and low input cost, and has high market value in the field of waste catalyst element recovery in the flue gas denitrification industry.

Description

technical field [0001] The invention belongs to the field of non-ferrous metal recovery, in particular to a method for recovering vanadium, tungsten / molybdenum and titanium elements from waste SCR denitration catalysts. Background technique [0002] With the continuous improvement of environmental protection awareness, in addition to coal-fired power plants, the emission standards for flue gas pollutants in industries such as steel, cement, and waste incineration have successively introduced restrictions on the concentration of NOx emissions. At present, as the mainstream flue gas denitrification technology in China, SCR denitrification technology is widely used in the NOx emission control of flue gas in different industries. The SCR denitrification catalyst is the key to the SCR denitrification technology. The harsh working environment usually results in a service life of only 2-3 years. The catalyst whose activity decreases and cannot be recovered by regeneration technolog...

AI Technical Summary

Problems solved by technology

The waste SCR denitrification catalyst not only contains B-level inorganic highly toxic substances V 2 o 5 and heavy metal oxides WO 3 or MoO 3 During use, it will also absorb highly toxic elements such as As, Hg, and Pb in the flue gas, and these toxic elements will bring great harm to the environment if they enter the environment

[0004] (2) Large output

[0005] (3) Many high value-added components

[0006] (4) Recycling is difficult, and efficient recycling technology is lacking

SCR denitration catalyst contains V 2 o 5 、WO 3 / MoO 3 and TiO 2 In addition, the use of forming aids in the production process will introduce SiO 2 、Al 2 o 3 And CaO and other components, and in the process of use, it will also absorb sulfur, alkali metals, phosphorus, arsenic, mercury, lead and other elements in the flue gas. The complex components will undoubtedly increase the recovery of high-purity vanadium, tungsten / molybdenum and titanium products. a certain degree of difficulty; in addition, the WO in the waste SCR denitrification catalyst 3 or MoO 3 content is often less than 5wt%, and V 2 o 5 The content is even below 1wt%, which is a great challenge for element recovery

At present, there is no mature technology and related units for the recovery of vanadium, tungsten / molybdenum and titanium elements in waste vanadium-titanium series SCR denitration catalysts.