Process gas discharged from a bypass pipe to a gas exhaust system can be prevented from diffusing back to the inside of a process chamber without having to install a dedicated vacuum pump at the downstream side of the bypass pipe. The substrate processing apparatus includes a process chamber accommodating a substrate, a gas supply system supplying process gas from a process gas source to the process chamber for processing the substrate, a gas exhaust system configured to exhaust the process chamber, two or more vacuum pumps installed in series at the gas exhaust system, and a bypass pipe connected between the gas supply system and the gas exhaust system. The most upstream one of the vacuum pumps is a mechanical booster pump, and the bypass pipe is connected between the mechanical booster pump and the rest vacuum pumps located at a downstream side of the mechanical booster pump.

Substrate Processing Apparatus

An exhaust emission control device for an internal combustion engine, capable of supplying a just enough amount of reducing agent to a selective reduction catalyst even when a NOx purification ratio of the catalyst is changed by various causes, thereby enabling a high NOx purification ratio and very low exhaust emissions to be maintained. An ECU calculates a filtered value based on a signal from an exhaust gas concentration sensor, calculates a moving average value of a product of the filtered value and a reference input, calculates a control input such that the moving average value becomes equal to 0, and adds a reference input to the control input to calculate an FB injection amount. The ECU calculates an FF injection amount with a predetermined feedforward control algorithm, and adds the FF injection amount to the FB injection amount, to thereby calculate a urea injection amount.

Exhaust emission control device for internal combustion engine

An object of the invention is to provide an exhaust emission control device which eliminates the use of a heat-retention structure using heat-insulating material such as glass wool so as to attain substantial lessening in production cost. A discharge end of a gas gathering chamber is connected to an entry end of a mixing pipe so as to encase the entry end of the mixing pipe and close an opened end face in a required spaced-apart relationship. Moreover, a side surface of the entry end of the mixing pipe adjacent to the discharge side of the particulate filter is formed with an opening; and gas guide passages are formed in the gas gathering chamber by guide fins for tangential introduction of all of the exhaust gas from the discharge side of the particulate filter to the opening. An extra space isolated from the gas guide passages is ensured in the gas gathering chamber as a heat-retention chamber surrounding the entry end of the mixing pipe.

Exhaust emission control device

An exhaust mixer (16) is provided for use in an engine exhaust system (10) downstream from an additive injector (14). The mixer (16) includes eight vanes (20), with four of the vanes (20A) extending from a first side (22) of the mixer (16) and arranged in an equally spaced circumferential array around a central axis (24), and the other four of the vanes (20B) extending from an opposite side (26) of the mixer (16) and arranged opposite from the other four vanes (20A) in an equally spaced circumferential array.

Exhaust Gas Additive/Treatment System and Mixer for Use Therein

An exhaust emission control device of an internal combustion engine, wherein an exhaust emission control valve (24) disposed in an exhaust pipe (22) of the internal combustion engine is approximately fully closed at the time of start and during the warming-up of the engine, the injection amount of a main fuel is increased over an optimum injection amount for fully opened exhaust emission control valve, and an auxiliary fuel is additionally injected during an expansion stroke, whereby unburned HC exhausted into the atmosphere at the start and during the warming-up of the engine is reduced remarkably.

Exhaust emission control device of internal combustion engine

An exhaust aftertreatment system comprises an injector for injecting urea water into an exhaust duct, and a denitration catalyst disposed downstream of the injector with respect to a flow of exhaust gas. The exhaust aftertreatment system reduces nitrogen oxides in the exhaust gas by the denitration catalyst while using ammonia produced from the urea water injected from the injector. The urea water is injected along a direction of the flow of the exhaust gas within the exhaust duct, and a porous plate is disposed in multiple stages in a space of the exhaust duct such that droplets of the injected urea water impinge against the porous plate before reaching a wall surface of the exhaust duct. A surface of the porous plate subjected to the impingement of the droplets is arranged to face downstream with respect to the flow of the exhaust gas. Deposition of the urea water is prevented by causing film boiling when the droplets impinge against the porous plate, and the urea water reflected by the porous plate is uniformly dispersed into the exhaust gas. Thus, the urea water is uniformly dispersed into the exhaust gas without increasing a pressure loss of the exhaust gas. The urea water is prevented from depositing on the wall surface and producing a precipitate in the form of a solid.

Exhaust aftertreatment system using urea water

An object of this disclosure is to provide a fuel injection device that can reliably detect an operation timing of a valve body, that is, a valve opening timing with high accuracy. The current of an electromagnetic valve reaches I2 at time t3, an FET 201 and an FET 221 are turned on, and a battery voltage VB is applied to the electromagnetic valve until time t5 is reached. The amount of displacement of the valve body reaches a target amount of control lift at time t4 between time t3 and time t5, that is, a movable core 304 comes into contact with a fixed core 301. The detection of the valve opening timing is performed during the period from time t3 to time t5.

Drive Device for Fuel Injection Device

A cylinder-shaped flow passage in which a first fluid flows includes an internal cylinder which is smaller in diameter than the flow passage. A swirl-generating stator having four vanes is radially fixed in the internal cylinder. A header space for supplying a second fluid is provided to the outer circumference of a wall surface of the internal cylinder in contact with flow separation areas which are formed along downstream surfaces of the swirl-generating stator as the first fluid runs into the swirl-generating stator. The wall surface of the internal cylinder is formed with openings through which the flow separation areas communicate with the header space. The second fluid supplied into the header space flows through the openings into the flow separation areas, and is diffused along the vanes of the swirl-generating stator to be swirled and mixed into the first fluid applied with swirling force by the swirl-generating stator.

Fluid mixing apparatus

A Study of a New Aftertreatment System (2): Control of Urea Solution Spray for Urea-SCR

PROBLEM TO BE SOLVED: To stably maintain the internal temperature of an injection valve at an appropriate level in an exhaust gas treatment apparatus for an engine in which a reducer is supplied into exhaust gases by the injection valve. SOLUTION: The reducer 16 is supplied into the exhaust gases 4 exhausted from the engine and flowing down an exhaust gas duct 5, and nitrogen oxides contained in the exhaust gases are removed from the exhaust gases by reducing/reacting the nitrogen oxides with the reducer on a selective reducing catalyst. The reducer is supplied into the exhaust gases by the injection valve 17. A cooling chamber 24 is so formed as to surround the injection valve. A cooling medium is circulated through the cooling chamber to cool the injection valve. COPYRIGHT: (C)2008,JPO&INPIT

Akira Nishioka

Papers

Exhaust aftertreatment system using urea water

Drive Device for Fuel Injection Device

Fluid mixing apparatus

A Study of a New Aftertreatment System (2): Control of Urea Solution Spray for Urea-SCR

Exhaust gas treatment apparatus for engine