Some knowledge points of chimneys, Tower Structural Support Chimney manufacturers will explain to you

The tower chimney manufacturer believes that the FRP chimney is made of vinyl ester resin and glass fiber with sufficient corrosion resistance and temperature resistance to make a glass fiber reinforced plastic cylinder section of a certain diameter and wall thickness, and then installed inside the concrete outer cylinder wall or supported by a steel structure In the middle of the frame, it is an anti-corrosion structure used to discharge corrosive fumes. The application of FRP chimneys in the field of anti-corrosion at home and abroad has a history of nearly 40 years.

Tower Structural Support Chimney manufacturers believe that in industrial production, all chimneys or exhaust chimneys that discharge various treated and up-to-standard waste gases at high altitudes have anti-corrosion problems. The main factors to be considered in the anti-corrosion design of the exhaust chimney are: chemical composition, temperature, humidity, gas pressure and flow, and whether condensed acid will be formed on the surface of the cylinder wall. The dew point of the wall can be calculated from the composition, temperature and humidity of the discharge medium. There are the following situations:

1) Tower chimney manufacturers believe that under normal circumstances, high-temperature chimneys with a temperature above 150 are not easy to condense on the chimney wall, and condensed acid is rarely formed, so the corrosion is relatively light, such as chimneys that do not desulfurize in power plants.

2) The tower chimney manufacturer considers that the chimney whose temperature is lower than 150 and contains a large amount of corrosive gas and soluble salt is seriously corroded. For example, the tail gas of nitric acid production is vented, the gas temperature is less than 90 and the content of nitrogen oxides is relatively high; the tail gas of sulfuric acid production is vented, the gas temperature is less than 60 and contains a large amount of sulfur dioxide; Sulfur oxides, the flue gas temperature of alkali boilers in paper mills is below 110, and contains various sodium salts; the viscose workshop of chemical fiber factories discharges gases containing hydrogen sulfide, carbon dioxide and other gases at room temperature. In short, the chimney is generally severely corroded under the action of corrosive gases and dusts below the dew point temperature of the flue gas.

Tower chimney manufacturers believe that the common corrosive gases in power plant desulfurization chimneys are unpurified sulfur dioxide and residual sulfur trioxide. Sulfur dioxide turns into sulfurous acid when it meets water, and sulfur trioxide turns into sulfuric acid when it meets water. Through ion exchange with hydrates in sulfuric acid concrete, soluble calcium salts, aluminum salts, iron salts and silica gels are generated. Alumina in clay bricks can also form soluble salts with sulfuric acid. Salt in flue gas is also a medium that cannot be ignored. Many soluble salts can penetrate the interior of bricks and concrete, absorb moisture and then crystallize and expand, destroying the material structure. The solid dust in the flue gas causes certain wear on the inner wall of the chimney, and this factor should be properly considered when selecting the material and lining of the chimney.

The tower chimney manufacturer believes that the chimney that emits dry flue gas is seriously corroded at the upper part of the chimney, which is easily affected by the outdoor air and is prone to form acid condensation. For chimneys with inner linings, the parts where corrosive medium easily invades, one is the junction of the inner lining section, such as the bracket supported by the outer cylinder; secondly, the flue gas medium passes through the gap of the brick masonry: entering between the outer cylinder and the inner lining , which corrodes the outer wall.

Tower chimney manufacturers believe that wet chimneys and wet (semi-dry) chimneys with strong exhaust corrosion should be made of corrosion-resistant materials or lined with corrosion-resistant materials. According to different working conditions, different anti-corrosion materials and different structural forms can be used:

1) The flue and chimney with severe corrosion can be made of plastic, acid-resistant stone, acid-resistant brick, glass fiber reinforced plastic, stainless steel, alloy steel, titanium plate, etc. According to different corrosive media and working conditions.

2) For mildly corroded chimneys, acid-resistant concrete and coated linings can be used.

3) For chimneys with severe corrosion, it is generally not suitable to use brick outer cylinders. In chemical, metallurgical, papermaking, and boiler chimneys that are forcibly removed after corrosion, the corrosion basically occurs when the outer cylinder is brick masonry. Brick chimneys (including lined ones) are difficult to reinforce after corrosion, and are prone to lose stability due to local corrosion.