The first type is mainly reinforcing agent or supplemented by industrial salt, MnO2 _ 2, Fe2O3, sugar, urea, phosphorus and antimony sulfide, supplemented by sulfur-fixing agent. This kind of combustion improver can reduce the ignition point of fuel and promote combustion, but this kind of fast-burning oxidant is unstable, decomposes quickly after heating, and has a short action time on the combustion system. In addition, there are great security risks in the process of processing, transportation and storage of strong oxidants.
The second category is mainly composed of various metal oxides and tailings. In the process of use, metal ions have a certain particle size, and only after drying, decomposition and diffusion can they play a role. The combustion of coal is a fast reaction, and the expected catalytic cracking reaction of metal ions is a slow reaction, which must go through the processes of adsorption, complexation, cracking and analysis, and its effect is not timely.
The third category is dominated by organic molecules. 1. Organic alcohols: For example, China patent CN 1266089A is made of methanol, ethanol, Tween, Span and distilled water in a certain proportion. Secondly, common organic solvents such as plant enzymes, ether, acetone and ethyl acetate are used, such as China patent CN 1405283A. Thirdly, it is a combustion-supporting agent with lipophilic mineral oil, lipophilic vegetable oil, emulsifier and its hydrophilic surfactant as main raw materials. In the patents of Jinyuan Chemical Group, surface active catalysts, dissolution aids, penetrants and oily solvents are mainly used [18]. A new efficient coal-burning catalyst composed of alkyl alcohol ether, alkyl ester, phosphate ester, alkyl alcohol amide, olefin and aromatic compound can achieve triple effects of coal saving, emission reduction and coke removal without reforming the boiler [19].
The fourth category is mainly metal carboxylate, including acetate, succinate and fatty acid salt. For example, China patent CN 17 18699A uses acetate oxalate, acetate, oxalate, succinate, fatty acid salt, alkyl sulfonate, alkylbenzene sulfonate, sulfamate, maleate, fumarate, citrate, tartrate, tannic acid, lactate, hydroxy acid salt, benzoate, naphthenate, iso-carboxylate. This kind of metal carboxylate is unstable, and it is easy to form salt or oxide deactivation when burning. The reaction of metal ions is similar to that of the second combustion improver.