RU1770512C - Method and device for treatment of asphalt-concrete mix constituents - Google Patents

Abstract

Usage: processing components of the asphalt mix in the construction of roads. SUMMARY OF THE INVENTION: heating the components of a mixture is carried out sequentially: first of a cementing material with the selection of its vapors and supplying fuel to its combustion zone. Then, after the operating temperature in the binder is reached, the stone material is heated while the vapor in the binder is fed into its fuel combustion zone. An apparatus for carrying out the method comprises a drying drum and a binder container with combustion devices connected to heat-producing fuel tanks. One end of the steam outlet is connected to the furnace fixture of the dryer drum. The other end of the steam vent with the upper part of the binder container. The flues at one end are connected to the upper part of the fuel tanks, at the other end are connected to the steam outlet between the additional locking and regulating bodies. 1 s.p. file, 1 ill.

Description

The invention relates to road construction and the building materials industry, in particular to the processing of components of asphalt mixtures used in the construction of roads.

A known method of processing the components of the asphalt mixture, including drying and heating stone materials and bitumen by burning preheated liquid fuel, dosing and mixing the components of the mixture.

A device for carrying out this method is known, comprising a dryer drum with a furnace and a fuel tank, a bitumen heater with a furnace and a fuel tank, material dispensers and a mixer. TO

Such devices include, for example, previously produced D597, D597A, D508-2 asphalt mixing plants. DS117-2E. The disadvantages of the method and device include environmental pollution by harmful gases released during the heating of bitumen and fuel oil.

A known method of processing the components of an asphalt mix is distinguished from the previous one in that, simultaneously with the heating of the bitumen, the harmful gases released from it are lived in the combustion device of the bitumen heater.

A device for implementing this method comprises a drying drum with a furnace fixture and a fuel tank and a bitumen heater with a furnace fixture and a fuel tank, prich VI about

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than the upper part of the capacity of the bitumen heater is connected by an air duct to the combustion device of the bitumen heater.

The disadvantage of this method and device is that the harmful gases released from the heated bitumen are burned only during the heating of the binder, and during the selection of the bitumen already heated in the batching agent and, further, into the mixer of the asphalt mixing plant, the harmful gases emitted emitted into the atmosphere.

Given that the heating of bitumen and the heating of stone materials occur in time sequentially and most of the time the bitumen heater does not work, a significant part of the harmful gases emitted from the hot bitumen pollutes the environment. In addition, no harmful gases emitted from the hot fuel during its heating and use will survive. Additional environmental pollution occurs. The disadvantages include the high fuel consumption for heating bitumen and stone materials.

A known method of processing components of the asphalt mixture, including heating stone materials and bitumen by burning heated liquid fuel with the afterburning of harmful gases released from hot bitumen, in the furnace fixture of the bitumen heater with the direction of the products of combustion in the heat exchanger of the bitumen heater during heating to direction mx in the regional heat exchanger in the absence of the need for heating bitumen.

A device for implementing this method is known, including a drying drum with a stacker, a flame control device and a fuel tank and a bitumen heater with a furnace, a flame control device and a fuel tank / 4 /. From the point of view of ecology, the bitumen heater included in such a device can be considered a heater that includes a thermally insulated tank with a heat exchanger in the form of a gas duct connected to a bypass pipe, an air duct in the upper part of the tank connected to a device for burning fuel, a bypass gas duct and switching device.

The specified method and device for its implementation is taken as a prototype,

The disadvantages of the prototype method include the following. In the absence of need for additional heating already

In the case of prepared bitumen, the fuel is burned for several hours only with the aim of burning off the harmful gases released from the hot fuel. Significant overconsumption of fuel is observed. When this fuel is burned, harmful environmental pollutants are also formed. No harmful gases released during fuel heating are burned.

0 device disadvantage. A prototype is the low durability of a fuel burner.

An object of the invention is to increase the efficiency of a method for treating components of an asphalt concrete mixture and a device for its implementation by reducing fuel consumption and environmental pollution.

This goal is achieved by the method of processing the components of the asphalt concrete mixture, which includes heating the cement and stone material by burning heated fuel, while subsequently heating the cement material with

5 by taking off its steam and feeding them into its fuel combustion zone, and then after reaching the operating temperature with the chewing material, while heating the stone material while simultaneously supplying vapors to the burning material in its fuel combustion zone. Moreover, when processing the components of the mixture, i.e. heated in burning and stone materials, also the combustion of vapors from

5 heated fuel.

The proposed method is based on the fact that heating of the fuel (by steam registers or electric heaters) and the boiler is carried out, as a rule, before heating

0 stone materials. Therefore, in the first period, when the fuel and bitumen are heated, the emitted harmful gases can only be burned in the combustion device of the bitumen heater. When the fuel and biomass are heated and the racing device of the bitumen heater is turned off, the furnace device of the drying drum begins to function, where stone materials are heated. This process is practically

0 lasts the entire shift. During this period, harmful gases emitted from hot bitumen and fuel can be burned in the furnace of the dryer drum. When using the proposed

5 of the method for processing the components of the asphalt mixture, its efficiency is increased due to the following factors (compared with the prototype):

- when bitumen is not heated, it is not necessary to specifically burn fuel with

the goal is to survive harmful gases (which also gives harmful emissions), because the combustion of these gases occurs simultaneously with the heating of stone materials, i.e. fuel economy and environmental pollution are reduced;

- burning combustible harmful gases released from heated fuel reduces the overall fuel consumption and reduces environmental pollution.

The afterburning of harmful gases released from combustible bitumen in the furnace fixture of the drying barbpan, and also the burning of harmful gases released from combustible fuel in the furnace fixtures of the bitumen heater and dryer drum, in the known methods of processing components of asphalt mixes, in the technical literature and in no operation is encountered. Therefore, the proposed method has novelty and significant differences.

To implement this method, there is provided a device comprising a drying drum and a bitumen heater with combustion devices, flame control devices and fuel tanks, the upper parts of the tank of the bigum heater and fuel tanks being connected by gas outlets through the shut-off-regulating organs to the furnace devices of the drying drum and the bitumen heater , the gas outlets are heated, and the shut-off-regulating bodies are connected to flame control devices. U-triad also has batchers of bitumen and stone materials and a mixer.

The connection of the upper part of the capacity of the bitumen heater with the furnace device of the drying drum increases the efficiency of the device, because allows you to burn the vapors released from the heated bitumen, the entire period of heating stone materials without additional fuel consumption, as is the case in the device / 4 /. and even with some reduction in fuel consumption, and. therefore, with reduced environmental damage.

The connection of the upper parts of the fuel tanks with the furnace fixtures of the bitumen heater and the dryer drum will allow harmful gases released from the heated fuel to be burned during the entire period when the bitumen and stone materials are heated. Reduces fuel consumption since these gases are combustible, and environmental pollution is reduced.

The gas outlet must be heated, as bitumen vapors, condensing and solidifying, can form plugs in the gas outlet that cannot be eliminated without heating.

The interconnection of the gas pressure regulating devices with the flame control devices allows the harmful gases to be directed only to the combustion device that is functioning at the given moment. When the torch breaks or the fuel supply is cut off, the supply of harmful gases for combustion to this furnace device is turned off.

Examples. The components of the asphalt mixture are treated in a manner known per se and proposed as a prototype. The effectiveness of the methods is estimated by the average hourly fuel consumption and the amount of harmful gases polluting the environment.

In both cases, the heating of bitumen lasts 2 hours, and the subsequent heating of stone materials - 6 hours.

The results are tabulated. EXPERIENCE 1.

Processing the components of the asphalt mixture in a known manner.

The bitumen is heated for 2 hours at a fuel consumption of 25 kg / h. The vapors released from it are burned in the furnace of a bitumen heater. Emissions from the combustion of fuels and the release of fumes from the fuel tanks where the fuel is heated are 2.77 kg / h. After the bitumen heating is completed, the furnace of the bitumen heater continues to operate with a fuel consumption of 10 kg / h. Vapors of hot bitumen are burned therein. Flue gases are bypassed by a bitumen boiler. The emission of harmful gases is 1.22 kg / h.

Immediately after the completion of the heating of the bitumen, heating of stone materials begins, lasting 6 hours. The fuel consumption is 270 kg / h. Emissions of harmful gases - 29.9 kg / h. On average, for every 8 hours of operation, 216.3 kg of fuel is burned and 24.2 kg of harmful gases are released into the atmosphere.

After heating the bitumen and stone materials, the components of the mixture are metered and mixed.

EXPERIENCE 2.

Processing the components of the asphalt mixture of the proposed method.

Bitumen is heated for 2 hours. Fuel consumption 24.8 kg / h, i.e. slightly lower due to the combustion, along with liquid fuel, of the vapors released during heating of the fuel in the fuel tanks of the bitumen heater and dryer drum. For the same reason, the emission of harmful substances into the atmosphere is reduced - 2.74 kg / h.

After the heating of the bitumen is completed, the heated stone materials begin to dose and mix the components of the mixture. Simultaneously with the heating of the stone materials, bitumen vapors and vapors released from the heated fuel are burned in the dryer drum furnace. The hourly consumption of liquid fuel in the furnace of the dryer drum is 269 kg, while emissions of harmful substances are 29.88 kg / h. The total average consumption of liquid fuel during the processing of the components of the asphalt mix is 207.9 kg / h. The total average emissions of harmful substances is 23.1 kg / h.

Comparing the known and proposed methods of processing the components of the mixture, it can be noted that in the proposed method, the average hourly fuel consumption is reduced, compared to the consumption when using the known method, by 8.4 kg, i.e. by 3.9%. At the same time, emissions of flue gases into the environment are reduced by 1.1 kg / h.

Thus, the effectiveness of the proposed method for processing the components of the asphalt mix in terms of reducing fuel consumption and reducing environmental pollution is quite large.

The drawing shows a structural diagram of a device for implementing the proposed method for processing components of the asphalt mix.

The device comprises a drying drum 1 with a combustion device 2, a flame control device 3 and a drying drum fuel tank 4, a bitumen heater 5 with a capacity of 6, a combustion device, a flame control device 8 and a continuous fuel tank 9 of a bitumen heater. The upper part of the tank b is connected by a gas outlet 10 to the furnace fixture 7. An additional steam pipe 11 is gas-cooled; unit 10 is connected to the furnace fixture 2 of the drying drum 1. To the steam pipe 11 are connected the gas ducts 12 and 13 of the corresponding fuel tank 4 of the drying drum and the fuel side 9 of the bitumen heater, Gas - the outlets and the steam line have a heating jacket 14 and locking and regulating bodies 15, 16, 17 and 18, connected by links 19 to the flame control devices 3 and 8. The device also contains a bitumen dispenser 20, dottgor of stone materials 21 and mixer 22.

The device operates as follows. The heaters of the continuous tank 9 are turned on. After 10 ... 15 min, the furnace fixture 7 of the bitumen 5 heater starts to work. The bitumen contained in the tank 6 is heated, from which harmful gases (hydrocarbons, benzpyrene, carbon monoxide) are released, mainly combustible. Control device

flame 8 opens the shut-off regulatory bodies 15 and 18. Hazardous gases are supplied to the combustion device 7 for afterburning. released in the tank 6 from bitumen and in the fuel tank 9 from hot fuel (fuel oil). At a predetermined time determined by the actual temperature of the fuel, heaters of the dryer drum tank 4 are turned on. With the shut-off regulatory body 17 open, harmful gases begin

to enter the combustion in the same combustion device 7. The consumption of fuel burned in the combustion device 7 is slightly reduced, pollution of the environment is significantly prevented

Wednesday.

When bitumen reaches the required operating temperature (130 ... 150 ° C), the heat treatment of the stone materials and the preparation of the asphalt concrete mixture begin.

The furnace device 2 is ignited, stone materials are fed to the dryer for heating. The flame control device 3, in connection with 19, opens the shut-off-regulating organ 16. The harmful gases released from the hot bitumen and fuel are fed to the combustion device for combustion. dryer drum.

The firing device 7 is turned off because further heating of bitumen in the tank

6 is not required. The flame control device 8 closes the locking-regulating organ 15. Since the combustion device 2 is more powerful and better structurally organized, the burning of harmful gases is improved. It is carried out during the time when the stone materials are heated, i.e., practically, until the end of the work shift.

The thermal jacket 14 prevents the bitumen vapor from condensing in the gas vents and (gas inlets, preventing the formation of bitumen plugs in them.

To: bitumen and stone materials, which have been reached to the required temperature, are supplied, respectively 07. into the bitumen doser 20 and the batcher

21 stone materials, and then into the mixer 22.

The furnace accessories of the dryer drum and the bitumen heater operate on liquid fuel (fuel oil) heated to a temperature of 1100-120 ° C. Fuel lines are not shown in the drawing.

Claims (2)

SUMMARY OF THE INVENTION 1. Method for processing components of an asphalt-free mixture, comprising heating in cement and stone materials by burning heated fuel, characterized in that, in order to reduce fuel consumption and prevent environmental pollution, the components of the mixture are heated sequentially: first of the burning material with the selection of its vapors and supplying fuel combustion in its direction, and then after reaching the burning material working temperature, the stone material is heated while vapors are fed into the fuel combustion zone of the fuel, 2. A device for treating a component of an asphalt mixture, comprising a drying drum and a container for baking with fire control devices having flame control devices connected to fuel tanks having heaters, characterized in that, in order to reduce fuel consumption and prevent environmental pollution it equipped with a steam vent with additional locking and regulating bodies, one end of which is connected to the furnace fixture of the drying drum, the other to the upper part of the tank for the flue gas duct, and gas ducts connected at one end to the upper part of the fuel tanks, with additional shut-off-regulating bodies installed in front of the combustion devices of the drying drum and the bin, and the gas ducts at the other ends are connected to the steam outlet between the additional shut-off regulating bodies. ".AT 269 kg / g 207.3 8.1. 2. 29.88 23.1 kg / h I.