RU46767U1 - INSTALLATION FOR PREPARATION OF ASPHALT CONCRETE MIXTURE AND DUST COLLECTION DEVICE - Google Patents

Abstract

The installation relates to the production of road-building materials, in particular asphalt mixtures, and can be used in asphalt plants and other construction industries. The objective is to create a plant that allows you to get high-quality and economical asphalt mixes, as well as reduce the amount of dust emitted during the operation of this plant by changing the dust collection system that allows you to effectively capture the smallest dust from mineral materials of this production. The task is achieved in that, like the well-known, the claimed installation for the preparation of asphalt concrete mixture contains a drying drum, bucket elevator, sorting device, weighing batcher, receiving hoppers, mixer, as well as a cleaning device, consisting of at least one dust fan a dust collector and connected by dust conduits to a drying drum and a sorting device. What is new is that it additionally contains a dust collection device connected by dust pipes to a screening device and a weight batcher. The task is also achieved by the fact that the dust collection device contains a dust fan, at least one dust collector and dust ducts. What is new is that the dust conduit from the dust collector to the weight batcher is made rectangular in a section perpendicular to the movement of the particle stream and has at least one expansion part, which in a section conducted parallel to the movement of the particle stream is a rectangular figure, the sides of which are connected in the upper part is an oval, while the height of the oval at the highest point is at least twice as large as the side of the figure.

Description

The installation relates to the production of road-building materials, in particular asphalt mixtures, and can be used in asphalt plants and other construction industries.

Known installation asphalt mixing DS-158, containing a drying drum, bucket elevator, sorting device, weighing batcher, mixer, storage bins and dust collection system connected by dust pipes to the drying drum and sorting device [1].

The disadvantages of this installation are the low quality of the resulting asphalt concrete mixture and the low efficiency of the resulting asphalt concrete mixture, as well as the large amount of contaminants emitted, mainly dust.

The objective is to create a facility that allows you to get high-quality and economical asphalt mixes, as well as reduce the amount of dust emitted during the operation of this unit by changing the dust collection system that allows you to effectively capture the smallest dust from mineral materials of this production

The task is achieved in that, like the well-known, the claimed installation for the preparation of asphalt concrete mixture contains a drying drum, bucket elevator, sorting device, weighing batcher, receiving hoppers, mixer, as well as a cleaning device, consisting of at least one dust fan a dust collector and connected by dust conduits to a drying drum and a sorting device.

What is new is that it additionally contains a dust collection device connected by dust pipes to a screening device and a weight batcher.

In addition, the dust pipe connecting the dust collection device to the weight batcher is made rectangular, and all the other dust pipes are made round in cross sections perpendicular to the movement of the particle stream.

In addition, the dust pipe with a rectangular cross-section has at least one expansion part.

In addition, a cyclone was used as a dust collector.

The task is also achieved by the fact that the dust collection device contains a dust fan, at least one dust collector and dust ducts.

What is new is that the dust conduit from the dust collector to the weighing batcher is rectangular in cross section perpendicular to the movement of the particle stream and has at least one expansion part, which in the cross section parallel to the movement of the particle stream is a rectangular figure, the sides of which are connected in the upper part is an oval, while the height of the oval at the highest point is at least twice as large as the side of the figure.

In addition, the dust pipe to the sorting device is made round in cross section. held perpendicular to the movement of the particle stream.

In addition, a cyclone was used as a dust collector.

In a known installation for the preparation of asphalt mixture in a known cleaning device, dust is separated from gas, while dust collection is not possible [2]. Due to the presence of new features during operation of the proposed installation, almost all dust from mineral materials of this production and especially dust of the smallest sizes is captured, which was impossible in the known installation .. As a mineral powder (fine fraction) in production, usually expensive limestone flour is used inconvenient to store, and the storage and supply system of mineral powder is cumbersome and problematic for the manufacturer. In the proposed installation, the use of mineral powder is excluded, and its need is compensated by dust, which in the process of obtaining the asphalt mixture is captured almost completely and continuously enters the process, namely, in one, common to all mineral materials, weight batcher .. Thus, a set of the complete composition of mineral materials takes place in one weight batcher, and since the saturation of mineral materials with trapped dust is continuous, the mineral materials are constantly mixed come together and already in the weight batcher they represent a homogeneous mass, which, when combined with heated bitumen in the mixer, mixes easily until a finished high-quality asphalt mix is formed.

In the known installation, the dust collection system is a system in which the dust collector operates on a vacuum, and in the proposed installation, the dust collector the dust collector operates under pressure. It is proposed that the dust conduit from the dust collector to the weighing batcher be rectangular in cross section perpendicular to the movement of the particle stream, and the expansion part, which in the cross section parallel to the particle flow movement, is made in the form of a rectangular figure, the sides of which are connected in the upper part by an oval, while the oval at the highest point is a value not less than twice as large as the side of the figure. Those. it is necessary to fulfill the following ratio:

H≥2 ₁ ,

where H is the height of the oval part of the sectional shape;

H ₁ - side height of the rectangular part of the sectional shape.

The implementation of dust pipes with the proposed cross-sectional shape and expansion part, the proposed configuration and dimensions on the dust pipe to the weight batcher is necessary to minimize the dust flow rate and coagulate dust particles in order to capture dust, including the smallest dust (less than 0.071 mm) in the weight batcher . It is these smallest dust particles that contribute to the formation of a loose, loose structure of an asphalt concrete mixture with improved quality characteristics

The proposed installation is illustrated by the drawings presented in figure 1 and figure 2

Figure 1 - schematically shows the proposed installation for the preparation of asphalt mix;

Figure 2 - presents a view of the expansion part of the dust pipe.

Figure 1 presents the proposed installation for the preparation of asphalt concrete mixture, which contains the feed hoppers of mineral materials of different fractions 1, 2, 3, conveyors 4, 5, dryer drum 6, bucket elevator 7, screening device (screen) 8, receiving bins 9, 10, a bunker of mineral materials of oversized fractions 11, a weight batcher 12, a mixer 13, a conveyor for unloading finished products 14, a cleaning device 15 (consisting of cyclones and a low pressure fan), a dust conveyor (screw) 16, a binder batcher 17 and a device Dust collection property 18 (consisting of a dust fan and cyclones).

Figure 2 presents a view of the expansion part of the dust pipe. from the dust collection device 18 to the weight batcher 12.

As a dust collector, a conical, helical cyclone can be used.

The sorting device is a screen.

The proposed installation works as follows. Mineral materials pre-metered in the feed hoppers 1, 2, 3, conveyors 4.5 are fed into the drying drum 6, where they are heated and fed through the tray to the bucket elevator 7, then to the sorting device (screen) 8, where they are dispersed in fractions. The fractions accumulate in the receiving hoppers 9, 10. And the strict dispensing of various fractions necessary for preparing a certain type of mixture occurs in the weight batcher 12. Dust with the smallest particle sizes continuously enters the weigh batcher, captured by the dust collector 18, which consists of a dust fan and dust collector (cyclone) and works on a mandatory principle. The dust captured by the cleaning device 15 is supplied together with the coarse and medium fractions to the sorting device 8. In the weight batcher 12, a complete set of well-mixed mineral composition takes place, which is fed to the mixer 13. The heated bitumen is also fed to the mixer 13 through the binder batcher 17. B mixer 13 mixes all the components with the formation of the finished asphalt mix.

The proposed installation allows not to use wet cleaning, save bitumen (up to 6%), save mineral materials (up to 5%), improve the quality of the resulting asphalt mix. The environmental effect of the installation: the degree of dust removal is 90.2% when using one expansion part on the dust pipe, when using two expansion parts on the dust pipe, the degree of dust removal is 93.4%. When the known installation, the degree of purification is only 61%.

Sources of information:

1. Installation asphalt mixing DS-158, technical description and operating instructions, M, Vneshtorgizdat, 1990

2. V.A. Timofeev et al., Technological equipment for asphalt concrete plants, Moscow, Mechanical Engineering, 1981, p. 95.

Claims (7)

1. Installation for the preparation of asphalt concrete mixture containing a drying drum, bucket elevator, sorting device, weighing batcher, receiving hoppers, mixer, as well as a cleaning device consisting of a dust fan of at least one dust collector and connected by dust pipes to the drying drum and sorting device, characterized in that the screening device with additionally introduced dust pipes is connected to a dust collection device and a weight batcher. 2. Installation according to claim 1, characterized in that the dust pipe connecting the dust collection device to the weight batcher is made rectangular, and all other dust pipes are made round in cross sections perpendicular to the movement of the particle stream. 3. Installation according to claim 1, characterized in that the dust pipe with a rectangular cross section has at least one expansion part. 4. Installation according to claim 1, characterized in that a cyclone is used as a dust collector. 5. A dust collection device comprising a dust fan, at least one dust collector and dust pipes, characterized in that the dust pipe from the dust collector to the weight doser is rectangular in cross section perpendicular to the movement of the particle stream and has at least one expansion part, which is in cross section drawn parallel to the movement of the particle stream is a rectangular figure, the sides of which are connected in the upper part by an oval, while the height of the oval at the highest point is not less than twice the side of the figure. 6. The dust collection device according to claim 5, characterized in that the dust pipe to the sorting device is made round in cross section perpendicular to the movement of the particle stream. 7. The dust collection device according to claim 5, characterized in that a cyclone is used as the dust collector.