Corrosion inhibitor for gas boiler ultra-low temperature flue gas and its preparation method and use method

Abstract

A corrosion inhibitor for gas-fired boiler ultra-low temperature flue gas and its preparation method and use method. In terms of mass percentage, 15-25% of water, 10-20% of polyoxyethylene sorbitan fatty acid ester, 5-10 % sorbitan fatty acid ester, 50-60% alkylamines with 12-18 carbon atoms are added in the reaction kettle, heated up to 50-55°C, stirred and homogenized, then naturally cooled to room temperature to obtain the intermediate product; 10 ~30% of benzotriazole, 20~30% of triethylenetetramine and 40~70% of intermediate products are added into the reaction kettle, and then the reflux reaction is complete. The dosage of the corrosion inhibitor of the present invention is very small, and the dosing concentration is 60-100 g / 10,000 m3 of gas per hour, and the cost is low. The invention makes the ultra-low temperature waste heat of the flue gas discharged outside the boiler, the temperature of the flue gas is reduced from about 145°C to about 60°C or lower, and the recovery process is realized. The invention effectively solves the problem of corrosion of induced draft fans and flue equipment by ultra-low temperature flue gas, and finally achieves the goals of energy saving, emission reduction, potential tapping and efficiency enhancement.

Description

technical field [0001] The invention belongs to the technical field of iron and steel metallurgy and chemical industry, and in particular relates to a corrosion inhibitor for gas-fired boiler ultra-low temperature flue gas and a preparation method and application method thereof. Background technique [0002] Laiwu Steel has 16 boilers of different types and sizes, with a total tonnage of 1920 tons per hour. Reducing the exhaust gas temperature of boilers is of great significance to improving energy utilization. In order to further recover heat, improve the actual operating efficiency of boilers, and reduce boiler exhaust emissions in energy and power plants. Increase the thermal efficiency of the boiler by increasing the flue gas temperature and increase the power generation. On the premise of ensuring normal production, consider every aspect of the entire boiler operation from the aspects of technology, efficiency, and safety, and combine the actual working conditions to stu...

AI Technical Summary

Problems solved by technology

In the existing technology, the temperature of the flue gas at 145°C is lowered to 120°C for discharge, which wastes heat and does not comply with the national emission policy

However, reducing the flue gas temperature will cause the water vapor in the flue gas to condense, and the corrosive substances (sulfur dioxide, sulfur trioxide, carbon dioxide, sulfide, etc.) produced after combustion will dissolve in the condensed water to form an acidic water film as the temperature decreases. Severe corrosion of flue gas pipes and rear equipment, such as fans