Preparation method of lignin-based paint spraying circulating water treatment agent

Abstract

The invention discloses a method of a lignin-based paint spraying circulating water treatment agent, which belongs to the technical field of paint sewage treatment. According to the technical scheme,the preparation method comprises the following steps: firstly performing the phenolation for industrial lignin, and then preparing the phenolated modified lignin into an aqueous solution with the weight percentage concentration of 15 to 40 percent. Preferably, the paint spraying circulating water treatment agent is phenolated lignin aqueous solution with the weight percentage concentration of 20 to 30 percent. The preparation method is simple in operation, suitable for solvent-type paint and waterborne paint, low in treatment cost, and good in treatment effect; and compared with the existing commercially-available commodity-type phenolic resin and melamine formaldehyde resin paint spraying circulating water treatment agent, the lignin-based paint spraying circulating water treatment agentprepared in the invention has the advantages of wide source of raw materials, low cost and good effect.

Description

technical field [0001] The invention belongs to the technical field of painting sewage treatment, and in particular relates to a method for preparing a spray painting circulating water agent based on modified lignin as the main material. Background technique [0002] In the process of workpiece painting, all the sprayed paint (paint) can be sprayed on the workpiece, so that a part of oversprayed paint is produced. In order to prevent the oversprayed (not painted on the workpiece) paint from flying, the painting process Most of them use water curtain or water cyclone to treat the oversprayed paint mist, so that the oversprayed paint mist enters the circulating water under the action of induced wind. However, if the circulating water is not treated with chemicals, after a period of time, the pipeline will be blocked and the circulating pump will be overloaded, and the paint mist will fly randomly, resulting in a decrease in the coating quality or even shutdown. In addition, t...

AI Technical Summary

Problems solved by technology

[0003] At present, there are three kinds of spray paint circulating water treatment chemicals on the market: the first one is sodium hydroxide (sodium carbonate) and polyaluminum chloride (ferric sulfate) as coagulant, and polyacrylamide as flocculant. The clarity of the circulating water can be guaranteed when the molded paint circulates water. Although the cost is low, as the alkalinity fluctuates, the debonding state of the paint slag is unstable, and it is easy to cause the blockage of the circulating water pipeline and the circulating pump blade, and the formed paint slag The high moisture content directly increases the outsourced treatment cost of paint slag, and is completely inapplicable to water-based paint circulating water systems

The second is to use montmorillonite with strong dispersion and adsorption effect as coagulant and polyacrylamide as flocculant. When this kind of chemical agent treats solvent-based paint circulating water, it can ensure the clarity of circulating water and debond paint residue. The state is stable, and the moisture content of paint slag can be effectively controlled by matching the component mass and charge density of polyacrylamide, but in the water-based paint spraying circulating water system, the treatment effect of this kind of agent is not ideal

The third is to use the aqueous solution of low molecular weight melamine formaldehyde resin or phenolic resin as the coagulant, and polyacrylamide as the flocculant, and add this kind of chemical in small doses continuously to the circulating water of spray painting. When painting, it also performs well, and is excellent in the clarity of circulating water, the degree of debonding of paint slag and the moisture content of paint slag, but the disadvantage is that the treatment cost is high, and the coagulant involves the use of formaldehyde. In addition, all chemical Products are from petrochemical raw materials

Images