Quaternary composite corrosion inhibitor for chemical cleaning of coal-fired boiler and application of quaternary composite corrosion inhibitor

The invention discloses a quaternary composite corrosion inhibitor for chemical cleaning of a coal-fired boiler and application. The corrosion inhibitor comprises carboxymethyl chitosan, sodium tartrate, dioctyl sodium sulfosuccinate and sodium iodide in a mass concentration ratio of (12-20): (5-8): (5-10): (8-10). The quaternary composite corrosion inhibitor disclosed by the invention is an environment-friendly corrosion inhibitor, does not have the risk of environmental pollution, and conforms to the current green development concept. The chemical components of the quaternary composite corrosion inhibitor have a certain synergistic effect, the raw materials are easy to obtain, the cost is low, and remarkable economic benefits can be generated when the quaternary composite corrosion inhibitor is used for chemical cleaning of boilers. The quaternary composite corrosion inhibitor has good corrosion resistance to Fe < 3 + > contained in a cleaning medium, and pitting corrosion damage caused by Fe < 3 + > in the