Coagulator for systems for the purifying of exhaust gases of fos

Details Coagulator for systems for the purifying of exhaust gases of fos Coagulator for systems for the purifying of exhaust gases of fos

1989-12-15

1991-04-09

Nozick, Bernard

Gas separation

Means within gas stream for conducting concentrate to collector

55135, B03C 300

Patent

active

050061348

DESCRIPTION:

BRIEF SUMMARY
PRIOR ART

The invention relates to a coagulator for systems for the purifying of exhaust gases of fossil fuels, in particular of exhaust gases from diesel internal-combustion engines.
In the case of such coagulators, also known as agglomerators or electrostatic soot separators, the particles contained in the exhaust gases, for example soot particles, are ionised in the electrostatic field developing between the electrode and the housing poled as counter-electrode. This involves the particles taking on electric charges, so that the particles coagulate, i.e. attract one another and join together to form sizeable agglomerates, which can be deposited more easily in downstream centrifugal separators, so-called cyclones.
A part of the agglomerates thus formed is already deposited in the coagulator. With time, deposits of electrically conductive agglomerates also occur in this way on the insulator ensuring the insulated leading of the electrode through the housing, which agglomerates would lead to short-circuiting of the insulator and consequently to the failure of the coagulator. In order to avoid this, it is necessary to heat the surface of the insulator in an annular region constantly to a temperature of over 400.degree. C. by means of an electric heating conductor track in the insulator. At this temperature, the depositing of agglomerates on the insulator is prevented. An agglomerate deposition which has formed after switching-off of the coagulator can be burned off, i.e. oxidised, by heating the insulator up to over 600.degree. C.
In the case of a known coagulator of the type mentioned at the beginning (DE 33 05 601 A1), an annular incandescent zone is produced on the surface of the insulator by means of the thick-film heating conductor track arranged underneath a top layer. This incandescent zone lies at the end of the insulator directly at the outlet point of the electrode from the insulator. This annular section must in this case be sufficiently far away from the electrode, i.e. the insulator must have a sufficiently great diameter, which must be at least 60 mm in the case of a high voltage of about 17 kV. With such a dimension of the insulator, considerable heat output is required due to the relatively large surface of the incandescent zone. In addition, with such a dimension of the insulator, the thermal stresses lead to crack formations and destructions. In addition, it is necessary to make the top layer for the heating conductor track resistant to high voltages, as a result of which the latter has to be dimensioned approximately the same as the insulator itself. In this case, an unavoidable parting line forms between the base material and the top layer of the insulator, which parting line does not achieve the dielectric strength of the base material. Disruptive discharges at the sides between a top layer and base material are therefore unavoidable.


ADVANTAGES OF THE INVENTION

The coagulator according to the invention has in comparison the advantage that the insulator only requires a relatively small outside diameter and consequently problems associated with thermal stresses do not occur. At a high voltage of about 17 kV, the insulator requires an outside diameter of only 18 mm for the certain avoidance of disruptive discharges. Due to the sintered-on protective tube, the heater winding is sufficiently far away from the parts carrying high voltage. The protective tube itself is resistant to high voltage, the parting line is gas-tight, so that no disruptive discharges can occur here either.
Advantageous further developments and improvements of the coagulator specified in claim 1 are possible by the measures given in the further claims.


DRAWING

The invention is described in more detail below with reference to exemplary embodiments represented in the drawing, in which:
FIGS. 1 to 3 show in a cutaway form in each case a longitudinal section of a coagulator for an exhaust gas purification system of diesel engines according to a first, second and third exemplary embodiment,
FIG. 4 shows a longitudinal

REFERENCES:
patent: 4618351 (1986-10-01), Esper et al.

Affiliated with

Also associated with

Rating

Coagulator for systems for the purifying of exhaust gases of fos does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Coagulator for systems for the purifying of exhaust gases of fos, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coagulator for systems for the purifying of exhaust gases of fos will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2032087