Metering system

Gas flaring in offshore installations and oil refineries represents a source of loss of energy making it important to operators and authorities to monitor the amounts of flared gas. In some countries the flare gas is subject to CO2 tax. Flow metering systems are installed on some but not all flare systems. 

In situ control and calibration of flare and other gas metering systems is performed by gaseous tracers using the transit time method without affecting the normal production. Details about methodology are given in / /. 

Oxygen Sensor and the Closed Loop Fuel Metering System... 

The function of the oxygen sensor and the closed loop fuel metering system is to maintain the air and fuel mixture at the stoichiometric condition as it passes into the engine for combustion ie, there should be no excess air or excess fuel. The main purpose is to permit the TWC catalyst to operate effectively to control HC, CO, and NO emissions. The oxygen sensor is located in the exhaust system ahead of the catalyst so that it is exposed to the exhaust of aU cylinders (see Fig. 4). The sensor analyzes the combustion event after it happens. Therefore, the system is sometimes caUed a closed loop feedback system. There is an inherent time delay in such a system and thus the system is constandy correcting the air/fuel mixture cycles around the stoichiometric control point rather than maintaining a desired air/fuel mixture. 

The performance of the catalytic converter is affected by the conditions of air/fuel control provided by the fuel metering system. A slowly responding fuel metering system can dramatically decrease the conversion efficiency of the converter compared to a fast response multipoint fuel injection system. 

The emission control system for LPG is the same as is used for gasoline fueled engines with the exception of the fuel metering system. No evaporative emission system is required. Both Pt—Rh and Pd—Rh catalysts are good for emission control of LPG fuel exhaust. Pt provides the lowest light off temperature for C Hg. The sulfur content of LPG is also very low so that Pd catalysts perform very well. 

Serth, R.W. and W.A. Heenan, Gross Error Detection and Data Reconciliation in Steam-Metering Systems, AlChE Journal, 32(5), 1986, 7.3.3-742. 

Consider now a situation in which the bias limits in the temperature measurements are uncorrelated and are estimated as 0.5 °C, and the bias limit on the specific heat value is 0.5%. The estimated bias error of the mass flow meter system is specified as 0.25% of reading from 10 to 90% of full scale. According to the manufacturer, this is a fixed error estimate (it cannot be reduced by taking the average of multiple readings and is, thus, a true bias error), and B is taken as 0.0025 times the value of m. For AT = 20 °C, Eq. (2.9) gives ... 

The metering of dry powder inhalers is closely linked to the device itself and may be divided into three common systems capsules, multidosing blister packs, and reservoir systems. The consideration that goes into these metering systems include convenience to the patients, stability on storage, compatibility with product, and ease of filling. 

Computer-assisted molecular modeling package, 10 331-333 Computer-assisted tomography (CAT), sodium iodide in, 22 827 Computer-automated image analysis, as a particle counting method, 18 146-149 Computer-controlled viscometers, 21 732 Computer controller, closed loop fuel metering system, 10 57 Computer control loop, components of, 20 677-678... 

Pet foods Ruminant feeds Feedback control, purpose of, 20 666 Feedback controllers, 20 666-667 tuning and stability of, 20 694 Feedback control systems, 20 691-695 Feedback loops, between science and technology, 21 615 Feed-back system, closed loop fuel metering system, 10 56 Feed characterization, in reverse osmosis, 21 666... 

Fuel injection, diesel, 70 60-61 Fuel injection systems, 70 51 Fuel injector detergents, 72 408 409 Fuel metering system dynamic (lag time), 70 50... 

Serth, R., and Heenan, W. (1986). Gross error detection and data reconciliation in steam metering systems. AIChE J. 32,733-742. 

Another well proved pressure gauge is equipped with a metallic membrane cell [54], The principle of this cell is the inclination of the membrane which causes the pressure-proportional variation of the electrical resistance of the system. The pressure range of those systems reaches up to 400 bar. The allowable temperatures of the metering system are near... 

The mixer-extruders proposed by the aforementioned manufacturing firms boast of high automation, control and monitoring levels. This feature characterizes not only the mixer unit but also the metering systems, vacuum and granulation devices. Moreover, the control system makes it possible to optimize the production process by obtain-... 

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