JPS59165815A - Regenerator for diesel particulate filter - Google Patents

Abstract

PURPOSE:To obtain a regenerator for burning a large amount of Pct by starting the burning of Pct by a burner at the initial stage of regeneration and putting- off the burner after the Pct in a filter is fired, and introducing only secondary air or a portion of exhaust from the downstream of DPF. CONSTITUTION:When Pct is deposited on a DPF 2, and the filtration resistance increases, regeneration of DPF 2 is required. In order to regenerate DPF 2, exhaust gas is bypassed by a selector valve 7 under keeping away from the DPF 2, and the burning Pct by a burner 3 is started from the upstream of the DPF 2. After the firing is confirmed by a temperature sensor 10, the burner 3 is put off, and a secondary air valve 8 is switched to allow the secondary air to flow backward from the downstream of the DPF 2, and the Pct sticked onto the DPF 2 is burned only by the secondary air, and thus DPF is regenerated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for regenerating a diesel particulate filter with attached particulates.

Usually diesel particulate filter (DPF)
When regenerating PET, as shown in Figure 1, the burner heats and incinerates it from the upstream side of the side where PET is attached. Therefore, Pet is ignited from the direction A, and as it moves toward the direction B, the reaction heat on the surface is transmitted, and the temperature inside becomes higher.

As a result, the temperature of the internal cell 2a of the DPF 2 rises, causing cracks due to the temperature difference that occurs locally in the cell 2a, and melting damage of the cell 2a due to the temperature rise. The problem was that it was difficult to incinerate.

An object of the present invention is to provide a DPF regeneration device that solves the above-mentioned problems and can incinerate a large amount of Pct.

In the DPF regeneration device according to the present invention, in the initial stage of DPF regeneration, the burner from upstream of the DPF starts incinerating the PET, and when the temperature sensor or the like determines that the PET in the filter has ignited, the burner is extinguished. and switch the valve 2
This system is configured so that the above objective can be achieved by introducing only the secondary air or a part of the exhaust air from the downstream side of the DPF.

With reference to FIGS. 2 to 4 below, the DPF according to the present invention
An embodiment of the playback device will be described.

FIG. 2 shows the principle of the DPF regeneration device according to the present invention.
The incineration proceeds in the direction A as before, but the flow of regeneration gas is reversed and proceeds in the direction C, so the temperature inside the DPF can be kept lower than in the conventional case. As a result, a larger amount of Pct can be incinerated at one time than in the past.

In the first embodiment of the DPF regeneration device according to the present invention shown in FIG. 3, 1 is a diesel engine, 2 is a DPF, 3 is a burner, and 4
Secondary air passage to the DPF, 5 is a bypass passage, 6 is a secondary air passage to the burner, 7 is an exhaust pipe/gas switching valve, 8
9 is a secondary air valve, 9 is an exhaust outlet opening/closing valve, and 10 is a temperature sensor. A burner 3 is provided upstream of the DPF 2, and a secondary air passage 4 having a valve 8 flows downstream of the DPF 2, so that secondary air can be supplied from downstream of the DPF 2. A secondary air passage to the burner is connected between the burner 3 and the valve 8, and an exhaust opening/closing valve 9 is provided downstream of the confluence of the secondary air passage 4 and the exhaust pipe. .

Next, the operation of the above embodiment will be explained.

When Pet precipitates in DPF 2 and filtration resistance increases, D
Regeneration of PF 2 is required. To regenerate the DPF 2, first the exhaust gas is passed through the switching valve 7 to avoid the DPF 2, and then the Pe
After starting the incineration of t and confirming ignition using the temperature sensor 10, the burner 3 is turned off, the secondary air valve 8 is switched, and the secondary air is made to flow backward from the downstream of the DPF 2, and the PET attached to the DPF 2 is removed only by the secondary air. It is designed to be incinerated to regenerate the DPF.

The arrow indicates the flow direction during burner combustion, and the E arrow indicates the flow direction during secondary air combustion.

FIG. 4 shows a second embodiment of the present invention. In the first embodiment, secondary air was used as the regeneration gas, but in this second embodiment, a part of the exhaust gas is used. This is the difference. In the second embodiment, the exhaust gas is taken in from the bypass passage 5 through the switching valve 11, and after incinerating the DPF 2, it is discharged to the outside through the exhaust gas passage 12 through the valve 13, but the effects are generally the same in both cases. The arrow indicates the direction of flow during burner combustion, and the F arrow indicates the direction of flow during exhaust combustion.

As mentioned above, according to the present invention, at the beginning of DPF regeneration, the burner starts incinerating the PET from upstream of the filter, and after confirming that the PET has ignited via a temperature sensor, etc., the burner is turned off and the valve is closed. The incineration of the filter proceeds from the surface of the filter to the inside of the filter, whereas the flow of the regenerating gas is the opposite, so the temperature inside the filter can be kept lower than that of the conventional filter.

Therefore, it becomes possible to incinerate many Pets at once.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a method of incinerating PET on a normal DPF, Fig. 2 is an explanatory diagram of the principle of a DPF regeneration method according to the present invention, and Figs. 3 and 4 are respectively related to the present invention. , FIG. 3 is a block diagram of the first embodiment in which the regeneration gas is secondary air, and FIG. 4 is a block diagram of the second embodiment in which the regeneration gas is part of the exhaust gas. DESCRIPTION OF SYMBOLS 1... Diesel engine, 2... Diesel particulate filter (DPF), 3... Burner device, 4... Regeneration gas intake passage, 5... By/gas passage, 7...・Switching valve, 8, 11...Valve, 1o...
・Temperature sensor.

Claims (3)

[Claims] (1) In the case where a diesel or ticulate filter is recycled, there is a burner device provided upstream of the filter, a bypass passage sealed with a switching valve provided further upstream of the burner device, and a bypass passage sealed with a switching valve provided further upstream of the burner device. It consists of a regeneration gas intake passage with a valve installed on the downstream side and a temperature sensor installed near the filter, and in the early stage of regeneration, the exhaust gas is bypassed avoiding the filter and regulated by the burner. The diesel particulate filter is characterized in that after starting incineration and confirming ignition by the temperature sensor, the burner is turned off and the valve is switched to allow only regenerated gas to flow back from downstream of the filter to incinerate the filter. playback device. (2) The diesel particulate filter regeneration device according to claim 1, wherein the filter regeneration gas is secondary air. (3) The diesel filter regeneration device according to claim 1, wherein the filter regeneration gas is a part of exhaust gas.