摘要:
A process and device for local permeability evaluation and local regeneration of a particle filter consisting of several juxtaposed zones through which a flow of gas to be scrubbed is passed include the steps of and apparatus for measuring the temperature of the flow upstream from the filter, measuring the temperature in at least one of the zones forming the filter, evaluating the thermal inertia of at least one of the zones by relative measurement of the temperature or of the local resistance to the temperature upstream from the filter, deducing from this the local permeability of the filter and locally regenerating the filter.
摘要:
A device intended to measure fouling and to locally heat an electrical insulating medium. At least one electrically resistive heating element (6, 8) is associated with a fouling detection unit. The fouling detection unit includes metallic elements (6, 10) in contact, at at least two points, with the insulating medium. The resistance variation between the two points is measured and is directly linked with the fouling of the medium.
摘要:
The invention relates to a process for controlling a particulate filter in the exhaust of a Diesel engine using an after-treatment of the particulates while requiring a minimum amount of energy. The process according to the invention adapts the geometry of a filter placed in the exhaust gas flow according to predetermined strategies linked with the running of the engine, the process being such that it limits a mean back pressure of the engine which degrades engine efficiency.
摘要:
The present invention is a filtering unit providing after-treatment of the gases emited in the exhaust of Diesel engines, comprising a filtering set which includes at least one filtering element (11, 12, 13); at least one resistive element (3) which heats a zone (121, 122, 123) of one of the at least one filtering element; at least one detection device which determines fouling of the filtering set (1); a control (5), responsive to the at least one detection device, which controls independently each of the resistive elements, according to the fouling of the filtering set and electrical power available to the at least one resistive element. The resistive elements (3) can be each wound around a zone of a filtering element. The invention further relates to the associated process.
摘要:
A process and an assembly for eliminating nitrogen oxides (NO.sub.x) present in the exhaust gas of a lean-burn diesel or spark-ignition engine, is part of the exhaust line coming from the engine. At least one nitrogen oxides conversion catalyst is placed in the main exhaust line the catalysts having non-coinciding temperature ranges for which the NO.sub.x conversion is below a certain conversion coefficient (C.sub.min). At least one NO.sub.x trap placed upstream is the conversion catalyst(s) and intended to trap, then to release the nitrogen oxides. At least one line bypassing the main exhaust line contains at least one of the NO.sub.x trap(s); and at least one valve intended to modulate the flow of gas between the bypass line and the main exhaust line is provided so that the NO.sub.x trap(s) can trap the nitrogen oxides, notably when conversion catalyst(s) have a conversion coefficient below a predetermined value (C.sub.min) and so that said the NO.sub.x trap(s) means (4) can release the nitrogen oxides simultaneously with a conversion.
摘要:
The present invention relates to a process and to an assembly for eliminating nitrogen oxides present in the exhaust gas of an internal-combustion engine (1), said assembly being part of the exhaust line (2) coming from the engine and comprising:a nitrogen oxides conversion means,a heat exchanger (4) placed in a bypass line (5) situated upstream from conversion means (3), intended to cool said exhaust gas.According to the invention, the conversion means comprises several catalysts (3) placed in main exhaust line (2), said catalyst(s) having non-coinciding temperature ranges for which conversion of the nitrogen oxides is below a certain threshold (C.sub.min). Furthermore, at least one valve (6) is placed at the inlet of bypass line (5) and intended to modulate the flow of gas between said bypass line (5) and main line (2) so that said exhaust gas reaches catalysts (3) at a temperature where at least one of said catalysts is active.
摘要:
A process for forming metal components of controlled porosity by welding, in which a predetermined amount of metal elements (50) of oblong shape is introduced into a mold (10) in which it is distributed isotropically. The metal elements are then subjected to increasing pressure (P) until the component has its final shape. The walls of the mold are then held in position and an electric current (I) flows through the metal elements and welds them together by local melting at the points of contact due to the Joule effect.
摘要:
The present invention relates to a process for controlled injection of hydrocarbons into an exhaust line of a lean-burn internal-combustion engine, comprising catalytic elimination of the nitrogen oxides. The process according to the invention consists in injecting a certain amount of hydrocarbons upstream from the catalytic elimination, periodically and for a short time interval, by means of pulsed hydrocarbon injections. The frequency and the amplitude of the hydrocarbon pulses are preferably controlled according to the running conditions of the engine.
摘要:
At least one hollow zone is formed in a stack of at least one upper layer and one lower layer. The upper layer is patterned to form at least a first hollow region passing through said upper layer. The first hollow region is extended by a second hollow region formed in the lower layer by etching through an etching mask formed on the patterned upper layer. The etching mask is formed by a resin layer, positively photosensitive to an optic radiation of a predetermined wavelength, exposed to the said optic radiation through the stack and developed. The lower and upper layers of the stack are respectively transparent and opaque to said predetermined wavelength so that the patterned upper layer acts as exposure mask for the resin layer.
摘要:
A device for eliminating nitrogen oxides in an exhaust line of a lean-burn internal-combustion engine (1) a NOx trap (3) for trapping the nitrogen oxides, a system for regenerating the nitrogen oxides when the NOx trap is saturated, a hydrocarbon treating catalyst (2) placed upstream from the NOx trap (3), a hydrocarbon injector (4) placed upstream from hydrocarbon treating catalyst (2), a probe (7) for measuring the gas mixture strength. The hydrocarbon treating catalyst (2) is a partial (or controlled) hydrocarbon oxidation catalyst that cooperates with the NOx trap (3) for trapping the nitrogen oxides and that allows to obtain, at the outlet thereof, gases with a low oxygen (O2) concentration and with high carbon monoxide (CO) and hydrogen (H2) concentrations. A control unit is furthermore provided for recording and processing data coming from various detectors and/or stored in order to carry out effective regeneration of the NOx trap (3) without disrupting the smooth running of the engine.