Method for producing polymer-modified bitumen from recycled polypropylene

Abstract

The invention relates to highway construction, and more particularly to a technique for producing polymer-modified bitumen mixtures based on organic petroleum binders, and can be used in the construction, repair and maintenance of road surfaces in all climate zones across a road network. The invention addresses the problem of improving the physical characteristics of a mixture, and more particularly its strength and its resistance to deformation at low temperatures. The technical result achieved by the solution to this problem is that of raising the softening temperature of a polymer-modified bitumen and improving the heat resistance thereof, as well as the stability of the mixture across a wide range of working temperatures. A method for producing a polymer-modified bitumen is proposed which includes heating bitumen to a liquid state at a temperature of not more than 180°С, then adding recycled polypropylene and continuously mixing for 120 minutes while maintaining a stable temperature for uniform melting of the solid components, wherein the feedstock is bitumen and recycled polypropylene in the following proportions: 97 wt% bitumen; 3 wt% recycled polypropylene.

Description

[0001] METHOD FOR PRODUCING POLYMER BITUMEN FROM RECYCLED POLYPROPYLENE

[0002] METHOD OF OBTAINING POLYMER BITUMEN FROM SECONDARY POLYPROPYLENE

[0003] The invention relates to road construction, namely to the technology of producing polymer-bitumen mixtures based on petroleum organic binders, and can be used in the construction, repair and operation of road surfaces in all road climatic zones.

[0004] A method is known for producing a polymer-bitumen composition based on bitumen, a polymer modifier and a plasticizer - an extract of selective purification of oil fractions, wherein bitumen with a softening temperature of 40-55 ° C is used as bitumen, a block copolymer of butadiene and styrene is used as a polymer modifier, and an extract of selective purification of residual oil fractions or an extract of selective purification of distillate oil fractions, which have a kinematic viscosity at 100 ° C of 12.7-24.3 mm2 / s, a pour point of 22-45 ° C, with the following ratio of components, wt.%: Block copolymer of butadiene and styrene 1-5; The above-mentioned plasticizer 5-18; The above mentioned bitumen The rest (RU No. 2237691 C2, 10.12.2002).

[0005] The disadvantages of this technical solution include poor compatibility of this type of polymer with bitumen; low extensibility of PBC; and poor elasticity of PBC.

[0006] The objective of the invention is to improve the physical characteristics of the mixture, namely its strength and resistance to low-temperature deformation.

[0007] The technical result of solving the stated problem is an increase in the softening temperature of polymer bitumen and an improvement in its heat resistance, as well as the stability of the mixture over a wide range of operating temperatures.

[0008] The specified technical result is achieved by the fact that a method for obtaining polymer bitumen is proposed, which includes heating bitumen to a liquid state at a temperature of no more than 180°C, then adding secondary polypropylene and continuously mixing for 120 minutes while maintaining a stable temperature for uniform dissolution of the solid components, and bitumen and secondary polypropylene are used as raw materials, with the following ratio of components, by weight. %: - Bitumen - 97;

[0009] - Recycled polypropylene - 3.

[0010] To implement the method, a laboratory stirrer with heating was used, which contains a metal container (1), an electric motor with adjustable rotation speed (2); a screw (3); a pulley (4); a heating plate (5); and a stand (6) as shown in Figure 1.

[0011] The method for obtaining a polymer-bitumen mixture is as follows:

[0012] 1) heating bitumen to a liquid state up to 180°C without overheating or compacting the raw material.

[0013] 2) Gradually add recycled polypropylene into the center of the resulting vortex while continuously mixing for 120 minutes. The lid should be closed to prevent heat loss. Dissolution of the recycled polypropylene in the mixture occurs by maintaining the temperature and continuous mixing.

[0014] After mixing is completed, tests are carried out to check compliance with standards.

[0015] The following were used as initial components: bitumen grade BND 100 / 130 and recycled polypropylene.

[0016] The resulting polymer bitumen complies with the standards of the Republic of Kazakhstan ST RK 2534-2014 "Bitumen and bitumen binders. Modified petroleum bitumen, road. Technical conditions."

[0017] The tests were conducted according to the following standards: ST RK 1226-2003 "Bitumen and bituminous binders. Method for determining the depth of needle penetration", ST RK 1227-2003 "Bitumen and bituminous binders. Determination of the softening point by the ring and ball method".

[0018] The results of the study of the mixture of bitumen BND 100 / 130 - secondary polypropylene are shown in Table 1.

[0019] Table 1

[0020] Table 1 presents the results of laboratory analyses of the physical characteristics of three samples with different component ratios.

[0021] Sample 1: Using 98% bitumen and 2% recycled polypropylene, the needle penetration depth is 51.2 x 0.1 mm at 25°C, which meets standard requirements. However, the softening point values ​​do not meet the standard.

[0022] Sample 2: with a component ratio of 97% bitumen and 3% recycled polypropylene, the needle penetration depth and softening temperature values ​​meet the standard requirements - 41.3 and 65, respectively.

[0023] Sample 3: Here, the needle penetration depth also does not meet the requirements, and the softening point is above the maximum permissible value. These deviations indicate that these samples are not suitable for compliance with the standard.

[0024] As can be seen from the presented data, the claimed method for producing polymer-bitumen mixtures allows:

[0025] - increase the softening temperature of polymer bitumen;

[0026] - improve its heat resistance;

[0027] - stability over a wide range of operating temperatures.

[0028] The data complies with the standard ST RK 2534-2014.

[0029] This approach also reduces the need to extract raw materials for polymer bitumen production from primary sources, which in turn reduces the negative impact on the environment and reduces energy costs associated with the extraction and transportation of raw materials.

[0030] Thus, the use of recycled polypropylene in the production of polymer bitumen promotes sustainable development and helps to minimize the negative impact of human activity on the environment.

Claims

CLAUSES OF THE INVENTION A method for producing polymer bitumen from recycled polypropylene, which includes heating the bitumen to a liquid state, characterized in that the bitumen is heated at a temperature of no more than 180°C, then recycled polypropylene is added and continuously mixed for 120 minutes while maintaining a stable temperature for uniform dissolution of the solid components, and bitumen and recycled polypropylene are used as raw materials, in the following ratio of components, wt. %: - Bitumen - 97; - Recycled polypropylene - 3.

Images