Resource utilization method of paint slag

Abstract

A resource utilization method of paint slag includes the following steps that (1) pretreatment and separation are conducted, specifically, the wet paint slag is pretreated through a grinding modified spray drying method and separated into two components which are powdery or granular slag and organic matter waster liquid, or the wet paint slag is pretreated and separated into two components which are solid slag and organic matter waster liquid through an acid-modified baking hardening treatment technology; and (2) the water-containing organic matter waster liquid obtained in the step (1) is placed in a stirring tank, an emulsifying agent and a modifier are sequentially added into the water-containing organic matter waster liquid with constant stirring, uniform stirring is conducted, and a product is obtained. According to component characteristics of the wet paint slag, the wet paint slag is pretreated and separated into the two components which are the solid slag raw material convenient to use and the organic matter waster liquid containing volatile matter, namely water, and then the water-containing organic matter waster liquid is made into the liquid-state coal clean combustion improver; and the process method is simple, safe and free of secondary pollution, takes effect rapidly, is low in treatment or utilization cost, and is good in economical efficiency.

Description

technical field [0001] The invention relates to the field of environmental protection and waste utilization, in particular to a resource utilization method of paint waste residue. Background technique [0002] Paint slag is mainly a waste formed by the condensation of spray paint mist and de-sticking flocculation suspending agent in the process of automobile painting (generally, the painting efficiency of ordinary air spray guns is only 20% to 40%, and the painting efficiency of electrostatic spraying is about 60%. A large amount of paint in the spraying operation is splashed in the spray booth cover, and the circulating water in the spray booth absorbs the paint mist and condenses. The paint workshop of the automobile industry produces 2.5-5kg of paint slag for each vehicle), mainly from the intermediate coating, color paint, surface paint and thinner. The basic composition of paint slag varies with the type or composition of the paint used. For example, the composition of...

AI Technical Summary

Problems solved by technology

Objectively speaking, landfill or sanitary landfill not only wastes a lot of land resources, but also causes further pollution of soil and groundwater.

[0008] 2) Incineration and pyrolysis incineration method. Due to the characteristics of paint slag (bonding, high water content and a large amount of halogen resin, etc.), the conventional incineration treatment method of paint slag is not only difficult to feed, but also requires a lot of energy for incineration, and causes air pollution and production Toxic and harmful gases such as dioxin

[0012] However, the existing thermal drying treatment, recovery and regeneration technology of paint slag has high requirements on the physical properties of paint slag, that is, paint slag must be classified in a timely and accurate manner. If the molecular structure of paint slag is basically destroyed, it cannot be rebonded under the action of solvents. , the paint slag cannot be re-used by thermal drying treatment, and the process design of the existing domestic automobile painting workshop basically needs major technical transformation to solve the situation that the molecular structure of the paint slag is not seriously damaged

Second, in order to maintain the physical and chemical properties of the resin molecules, it is necessary to select a suitable paint mist coagulant. The currently used flocculation and detackifiers are very destructive to the molecular structure of the paint resin.

The third is that the heat transfer and volatilization separation efficiency of the heat treatment is low, the energy consumption is large and the time is long. To prevent the irreversible damage to the resin structure, the temperature and time of the dehydration and drying process must be strictly controlled.

Four washing needs to use a lot of water or methanol, the process produces secondary pollution

However, the combustion performance of the cement substitute fuel prepared by this method is extremely poor in objective application, and it is difficult to catch fire and fully burn when used alone, and a large amount of toxic and harmful pollutants dioxins will be produced.

[0025] Chinese patent CN203474658U discloses a cement production equipment using waste paint slag as an auxiliary fuel, and provides a device for adding paint slag from the tertiary air duct into the connection port of the calciner. Its essence is to use the high temperature from the tertiary air duct Oxygen-containing (local air oxygen concentration) hot air (generally 950-1200 ℃), so that the water-containing paint slag that is not easy to catch fire can be ignited and burned in the calciner. Working conditions increase coal consumption

[0027] Obviously, the application of the existing paint slag as an alternative fuel technology to cement kilns has the technical difficulties of obviously affecting the kiln working conditions, increasing the amount of fuel and even increasing pollution, and the amount of disposal is low

[0028] To sum up, although the research and application of paint slag has achieved a lot of remarkable results, so far, the problem of environmental protection disposal of paint slag has seriously plagued enterprises and affected the benefits of enterprises, and a large amount of paint slag has to be piled up or sanitary filling Burying or consuming high incineration costs to directly incinerate in professional incinerators urgently needs a new method that is economical and has no secondary pollution to achieve green, low-carbon, circular economy development