Method for producing asphalt warm mix wax

Abstract

The invention discloses a method for producing a wax for warm mixing of asphalt. According to the method, a polyethylene wax by-produced from polyethylene is taken as a raw material and is sweated for preparing a target product. According to the method disclosed by the invention, on the basis of a common sweating technology, air flow is utilized to carry a liquid component by a wax layer so as to forcefully separate a solid component from the liquid component in a sweating process, and meanwhile, optimally, aqueous solutions of more than two matters capable of reacting and generating gas are respectively emulsified and then sweated and the quick emission of the liquid component is benefited, so that the low molecular weight components are effectively removed from the raw material. The method disclosed by the invention has the advantages of low equipment investment, simple preparation process, low operation cost, safety, energy-saving effect, no solvent pollution, and the like. The acquired product can be used for reducing the mixing temperature of the asphalt while promoting the anti-track property of an asphalt road.

Description

technical field [0001] The invention belongs to the technical field of special wax production, in particular to a method for producing wax for asphalt warm mixing. Background technique [0002] The asphalt mixture used in road engineering is generally divided into three types according to the mixing construction temperature: hot mix asphalt mixture HMA (Hot Mix Asphalt), cold mix asphalt mixture CMA (Cold Mix Asphalt) and warm mix asphalt mixture WMA (Warm Mix Asphalt). [0003] Hot mix asphalt mixture is widely used and has good road performance. However, the production process of hot mix asphalt mixture needs to be mixed at 150-180°C, which consumes a lot of energy and produces a lot of smoke and CO. 2 , CO, SO 2 , NO x and other harmful gases, which not only pollute the environment but also affect the health of the staff. At the same time, mixing under high temperature conditions is also likely to cause thermal aging of asphalt, which reduces the service time of aspha...

AI Technical Summary

Problems solved by technology

When the ordinary sweating process produces soap wax and low melting point paraffin wax at 40°C to 60°C, the solid component (wax with a higher melting point) and the liquid component (wax with a lower melting point) in the sweating process are two types of components. They are in two phases of solid and liquid respectively, but it is difficult to completely separate them

In order to make the final product meet the requirements, the method of prolonging the sweating time (reducing the heating rate) and increasing the sweating termination temperature is usually adopted, but this will lead to a long production cycle and a decrease in product yield; tests have shown that the common sweating process produces products with a melting point above 70°C. For wax products, the carbon distribution width and n-alkane content on the wax in the later stage of sweating have nothing to do with the yield, that is, the carbon distribution width on the wax does not decrease with the decrease of yield, and the n-alkane content does not increase with the decrease of yield, so So far, there is no report on the production of wax products with a melting point of about 70°C by sweating process

[0017] Compared with solvent separation, the sweating process is an intermittent operation, and the product yield is lower and the production cycle is longer, but the sweating process has the advantages of less investment, simple production process, low operating cost, safe production process, energy saving and no pollution to the environment, etc. Advantages, some manufacturers are still using this method to produce soap wax products

[0018] Over the years, the sweating method has been developed in terms of production equipment and technology, such as CN89214332 (vertical square multi-section sweating tank), CN94223980.6 (dish-type sweating device), CN98233254.8 (paraffin sweating tank), CN200920033500. X (new paraffin sweating tank), CN201210508905.0 (a high-efficiency paraffin sweating device), CN201320127680.4 (tubular paraffin deoiling device), etc., improved sweating equipment; CN91206202 (a high-efficiency paraffin sweating tank) Improvements have been made in the sweating process, but these improvements still cannot produce wax products with a melting point above 70°C

[0019] The existing asphalt warm mix agent usually reduces the 60°C viscosity of asphalt while reducing the mixing temperature of asphalt mixture, thus affecting the high temperature stability of asphalt mixture