Anticorrosion method for low temperature desulphurization chimney lining, and acid-resistant injection material

Abstract

The invention provides an anticorrosion method for low temperature desulphurization chimney lining and an acid-resistant injection material, belonging to the field of chimney lining anticorrosion technology. The acid-resistant injection material is composed of waste electromagnetic aggregate, glass-ceramic powder, nanometer fine silica powder, modified sodium silicate, glycol and a furan resin, wherein a ratio of powder to liquid is 10: 3 to 10: 2 and powder and liquid are separately stored. Metal ceramic composite bolts, titanium wires and an externally hung metal net having undergone anticorrosion treatment form an integral structure; the inner wall of a chimney sleeve is subjected to enclosed treatment with an organic silicon rubber resin; during construction by using a wet injection process, a small amount of the furan resin is added, and the furan resin is uniformly distributed on the surface of a particle; during curing of the injection material, the organic silicon rubber resin migrates to a surface layer and is then acidified by using dilute sulphuric acid with a certain concentration, thereby forming a compact acid-resistant impervious film on the surface of a hardened body, so acid solutions like dilute sulfuric acid and dilute hydrochloric acid are prevented from infiltrating into the injection material, and thus, an integral composite anticorrosive working coating for the chimney lining is formed. The composite anticorrosive coating improves integrality of the chimney, endures influence of humidity gradient and flue gas pressure and influence of alternating thermal stress generated during desulphurization failure, and compensates for disadvantages of a variety of anticorrosion systems at present.

Description

technical field [0001] The invention relates to a low-temperature desulfurization chimney lining anticorrosion method and an acid-resistant injection material, belonging to the technical field of chimney lining anticorrosion. Background technique [0002] At present, more than 90% of domestic flue gas desulfurization adopts wet desulfurization process, and most of them do not have heat exchanger (GGH) equipment. The flue gas temperature after wet desulfurization is between 40-50°C, although SO 2 is removed over 90%, but SO 3 The desulfurization effect is very low, no more than 20%. At 40-50°C, SO 3 , HCL, HF and other gases below their dew point temperature, form H 2 SO 4 , HCL, HF, HNO 3 Corrosive acid liquid; under the dual effects of humidity gradient and flue gas pressure, the formed acid is highly permeable and corrosive, which affects the durability of the chimney structure. In addition, when the desulfurization device fails, the flue gas temperature is generall...

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Problems solved by technology

[0003] At present, the anti-corrosion scheme of desulfurization chimney lining mainly adopts structural forms such as pasted foam vitrified bricks, glass fiber reinforced plastics, and titanium steel plates; because the wear resistance, thermal stability, and impermeability of domestic foam vitrified bricks cannot meet the current complex use of chimneys Environment: FRP is formed by glass fiber and resin through a certain process. The temperature during use should not exceed the softening temperature of the resin used. If the desulfurization failure time exceeds 30 minutes, it is necessary to cool down the gas entering the chimney to avoid the structural damage of FRP. Destruction; the inner lining of titanium steel plate is made of steel plate, and the titanium plate is used as the anti-corrosion layer. The biggest risk has always been the hidden danger of chimney lining corrosion

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