Utilization of Emissions from Reactors of a Delayed Coking Installation

2020 ◽  
Vol 24 (11) ◽  
pp. 4-9
Author(s):  
M.K. Dexenov ◽  
F.R. Ismagilov

The features of utilization of low-pressure gas emissions from reactors of a delayed coking installation are considered. A technical solution has been proposed for the compression and purification of low-pressure hydrocarbon gases from hydrogen sulfide by using a liquid-ring compressor with an amine solution mixed with a hydrocarbon fraction taken in a certain ratio as a working liquid. Gasolines, kerosene, diesel fuels and any other hydrocarbon mixtures with low viscosity can be used as the hydrocarbon fraction. Preferably use gaseous gasoline obtained during the compression of gas or distillate in the main distillation column. Test results and computational studies confirm the advantages of using a binary working fluid compared to using the components separately.

2020 ◽  
Vol 24 (11) ◽  
pp. 4-9
Author(s):  
M.K. Dexenov ◽  
F.R. Ismagilov

The features of utilization of low-pressure gas emissions from reactors of a delayed coking installation are considered. A technical solution has been proposed for the compression and purification of low-pressure hydrocarbon gases from hydrogen sulfide by using a liquid-ring compressor with an amine solution mixed with a hydrocarbon fraction taken in a certain ratio as a working liquid. Gasolines, kerosene, diesel fuels and any other hydrocarbon mixtures with low viscosity can be used as the hydrocarbon fraction. Preferably use gaseous gasoline obtained during the compression of gas or distillate in the main distillation column. Test results and computational studies confirm the advantages of using a binary working fluid compared to using the components separately.


Author(s):  
James F. Walton ◽  
Andrew Hunsberger ◽  
Hooshang Heshmat

In this paper the authors will present the design and preliminary test results for a distributed electric generating system that uses renewable energy source for economical load-following and peak-shaving capability in an oil-free, high-speed micro-turboalternator system using compliant foil bearings and a permanent magnet alternator. Test results achieved with the prototype system operating to full speed and under power generating mode will be presented. A comparison between predicted and measured electrical output will also be presented up to a power generating level of 25 kWe at approximately 55,000 rpm. The excellent correlation between design and test provides the basis for scale up to larger power levels. Based upon the turboalternator test results a thermodynamic cycle analysis of a system using low grade waste heat water at approximately 100 C will be reviewed. The tradeoff study results for a series of environmentally friendly refrigerant working fluids will also be presented including sensitivity to vaporization and condensing temperatures. Based on the cycle and pinch point analyses predicted maximum output power was determined. Finally a preliminary turbine design for the selected R134a working fluid was completed. The results of this study show that a net output power level of greater than 40 kW is possible for approximately 240 l/m flow of water at 100C is possible.


2021 ◽  
Vol 1 (2) ◽  
pp. 27-33
Author(s):  
M.V. Lyashenko ◽  
◽  
V.V. Shekhovtsov ◽  
P.V. Potapov ◽  
A.I. Iskaliyev ◽  
...  

The pneumatic seat suspension is one of the most important, and in some situations, one of the key components of the vibration protection system for the human operator of the vehicle. At the present stage of scientific and technical activities of most developers, great emphasis is placed on controlled seat suspension systems, as the most promising systems. This article analyzes the methods of controlling the elastic damping characteristics of the air suspension of a vehicle seat. Ten dif-ferent and fairly well-known methods of changing the shape and parameters of elastic damping characteristics due to electro-pneumatic valves, throttles, motors, additional cavities, auxiliary mechanisms and other actuators were considered, the advantages, application limits and disad-vantages of each method were analyzed. Based on the results of the performed analytical procedure, as well as the recommendations known in the scientific and technical literature on improving the vibration-protective properties of suspension systems, the authors proposed and developed a new method for controlling the elastic-damping characteristic, which is implemented in the proposed technical solution for the air suspension of a vehicle seat. The method differs in the thing that it im-plements a cyclic controlled exchange of the working fluid between the cavities of the pneumatic elastic element and the additional volume of the receiver on the compression and rebound strokes, forming an almost symmetric elastic damping characteristic, and partial recuperation of vibrational energy by a pneumatic drive, presented in the form of a rotary type pneumatic motor. In addition, the method does not require an unregulated hydraulic shock absorber, while still having the ad-vantage of improved vibration-proof properties of the air suspension of a vehicle seat over a wide range of operating influences.


Author(s):  
François Berot ◽  
Hervé Dourlens

This paper describes the synchronous vibration instability problem that occurred on a series of large overhung centrifugal compressors. The first part of this paper deals with the identification and display of the instability phenomenon: cyclic vibration amplitude variations and phase angle rotation occuring during testing of overhung centrifugal compressors. After numerical simulations and analysis of the test results, the bearing design has been identified as the cause of the problem. The second part describes the numerical study of the instability of the compressor. This problem is related to the eccentricity of the shaft in the bearing and to the shape of its orbit. We have investigated and propose different solutions to avoid this unstable dynamic behavior. These solutions have been tested on different compressors and have confirmed the results of the numerical analysis. The third part reminds a link between the thermal effect occurring in the bearings, the numerical results and the tested dynamic behavior of the compressor. Recently, some authors such as Keogh et al. (1994) and Liebich et al. (1994) have noticed and studied this unstable behavior. Althougth the nature of the phenomenon seems to be known (de Jongh et al., 1984) (Faulkner et al., 1997a, 1997b), no universal technical solution to this important problem has been found. The contribution of this work is to present another case of the influence of the thermal effect on the dynamic behavior of an overhung compressor. We present the typical symptoms of the phenomenon, explain it, and propose the solutions we have used to avoid the problem.


Author(s):  
H. R. Bankhead ◽  
C. E. Meece

Vibratory stress characteristics of the low pressure compressor in the Pratt & Whitney Aircraft PW1120 turbojet engine recently have been evaluated during full-scale engine testing at the United States Air Force’s Arnold Engineering Development Center. A description is presented of the approach used to evaluate the vibratory characteristics of the new three stage low pressure compressor. Results are presented showing the effects of simulated altitude conditions, inlet pressure distortion, and off-schedule variable vane operation. Strain gage data is compared to case-mounted light probe data, and the levels of system damping and mistuning are discussed. Predicted vibratory response is compared to test results showing the new compressor to be free of destructive vibration.


Author(s):  
Shun Chen

The hydraulic analogy was employed in a rotating water table for simulating the compressible two dimensional flow in a low pressure turbine stage. Both steady and unsteady forces were measured directly on a rotating blade in a blade row rotating concentrically with a row of stator vanes. With proper modeling of the simulation, it is shown that the rotating water table can yield results that agree favorably with the analytical predictions and turbine test results. Using this test facility, the effects of axial spacing between rotor and stator rows on the nozzle wake excitation have been investigated for two different stator vane profiles. The water table test results correlate qualitatively with the turbine test data. The cancellation of nozzle passing frequency excitation by off-setting nozzle pitch was demonstrated in the water table and the results compared with both the analytical predictions and the laboratory turbine test results.


Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5997
Author(s):  
Meike Ernst ◽  
Andrea Vacca ◽  
Monika Ivantysynova ◽  
Georg Enevoldsen

A novel virtual prototyping algorithm has been developed to design one of the most critical lubricating interfaces in axial piston machines of the swash plate type—the piston–cylinder interface—for operation with water as the working fluid. Due to its low viscosity, the use of water as a lubricant can cause solid friction and wear in these machines at challenging operating conditions. The prototyping algorithm compensates for this by tailoring the shape of the bore surface that guides the motion of each piston in this type of positive displacement machine to conform with the piston surface, taking into account both the piston’s tilt and its deformation. Shaping these surfaces in this manner can render the interface more conducive to generating hydrodynamic pressure buildup that raises its load-carrying capacity. The present work first outlines the structure of the proposed algorithm, then presents a case study in which it is employed to design a bore surface shape for use with two prototypes, one virtual and one physical—both modified versions of a 444 cc commercial axial piston pump. Experimental testing of the physical prototype shows it to achieve a significantly higher maximum total efficiency than the stock unit.


1950 ◽  
Vol 163 (1) ◽  
pp. 235-248 ◽  
Author(s):  
A. R. Howell ◽  
R. P. Bonham

Axial compressors, particularly near design conditions are, on the whole, amenable to analytical treatment, and usually a good estimate of their performance can be made before they are run. Away from the design points, the performances are conveniently thought of in terms of the overall characteristics of pressure-rises, temperature-rises, and efficiencies plotted against mass-flows. For these performance estimations the aerodynamicists must have knowledge of the stage and overall characteristics of previous compressors and of methods of predicting such characteristics. Obtaining the overall characteristics from a stage-by-stage calculation is a lengthy process, but, fortunately, simplified methods can often be used. In this lecture we have indicated some of the methods that are employed to obtain and predict the overall characteristics and their associated stage characteristics. Reference is made to test-results from various National Gas Turbine Establishment research compressors, one of which uses water instead of air as the working fluid, and also to published information on other compressors. The importance of blade and test errors on performance and analysis work is also emphasized. In our simplified method of analysis and prediction of overall characteristics we have reduced the individual overall characteristics at each speed to what are, in effect, mean stage characteristics plotted relative to their maximum-efficiency-point conditions. Then the maximum-efficiency-point conditions at the different speeds are plotted and considered separately.


1995 ◽  
Vol 117 (4) ◽  
pp. 767-776 ◽  
Author(s):  
P. Tang ◽  
A. B. Palazzolo ◽  
A. F. Kascak ◽  
G. T. Montague

An integrated, compact piezohydraulic actuator system for active vibration control was designed and developed with a primary application for gas turbine aircraft engines. Copper tube was chosen as the transmission line material for ease of assembly. Liquid plastic, which meets incompressibility and low-viscosity requirements, was adjusted to provide optimal actuator performance. Variants of the liquid plastic have been prepared with desired properties between −40°F and 400°F. The effectiveness of this hybrid actuator for active vibration control (AVC) was demonstrated for suppressing critical speed vibration through two critical speeds for various levels of intentionally placed imbalance. A high-accuracy closed-loop simulation, which combines both finite element and state space methods, was applied for the closed-loop unbalance response simulation with/without AVC. Good correlation between the simulation and test results was achieved.


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