Mehra process

Natural Gas Processing and Hydrocarbon Separation, Mehra Process, Encyclopedia of Chemical Processing and Design, McKetta, Editor, Marcel Dekker. Vol. 31, p. 35. 

Using Non-Cryogenic Absorption to Reject Nitrogen From Subquality Namral Gases - The Mehra Process Alternative, Gas Separation International Conference, Austin, TX, Apr. 22 - 24, 1991. 

Gas treatment also includes the recovery of various hydrocarbons associated with natural gas. There are several processes to achieve this goal lean gas absorption, various types of refrigeration, turboexpansion, and others. However, since there were certain disadvantages in these processes, there was need for a refined process which can eliminate some of these limitations to economically and efficiently recover the valuable hydrocarbons from natural gas. One of the major limitations of the conventional processes was the inflexibility to meet the market demand. A process called the Mehra Process has been patented to solve some of these problems [9], in which a physical solvent is used for the removal and recovery of only desirable hydrocarbons from the gas stream. Basically, this is an extraction process since the volatility of hydrocarbons is increased on contact with a physical solvent. The equipment used for this process are arranged in two different configurations extractive-flashing and extractive-stripping. 

Mehra (1) [Named after the inventor] A process for extracting particular hydrocarbons from natural or synthetic gas streams using solvent extraction into polyalkylene glycol dialkyl ethers. Invented in 1982 by Y. R. Mehra at the El Paso Hydrocarbons Company, Odessa, TX. U.S. Patent 4,421,535. 

Mehra (2) [Named after the inventor] A gas separation process utilizing absorption in a solvent at moderate pressures. Developed by Advanced Extraction Technologies and applied to hydrogen recovery, nitrogen rejection, and recovery of natural gas liquids. 

GEN.26.1. Prigogine, Measurement process and the macroscopic level of quantum mechanics, in The Physicist s Conception of Nature, J. Mehra, ed., Reidel, Dordrecht, 1973, pp. 697—701. 

Mehra and Ayon [76] developed the first micro structured hydrogen combustor made of silicon. The device was developed to power a micro gas turbine. However, it could also be applied for fuel processing and is therefore included in this chapter. 

The first part eoncerns the generation of the residuals (waved pattern in the Figure 1). In order to obtain an observer of the physical system, a real-time simulation is done in parallel. So, a eomplete state of the system will be available at any time. Thus, it is based on the eomparison between the predicted behavior obtained thanks to the simulation of the reference model (values of state variables) and the real observed behavior (measurements from the process correlated thanks to the Extended Kalman Filter). The main idea is to reconstruct the outputs of the system from the measurement and to use the residuals for fault detection (Mehra and Peschon, 1971, Welch and Bishop, 1995, Simani and Fantuzzi, 2006). A description of the extended Kalman filter ean be found in (Olivier-Maget et al., 2007). Besides the residual is defined aeeording to the following equation ... 

Mehra, Y. R., Refrigeration Systems for Low-Tenperature Processes, Chemical... 

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