Calculation of Organic Substrate Decomposition in Biofilm and Bioreactor-Filter Taking into Account its Limitation and Inhibition

2021 ◽  
pp. 75-77
Author(s):  
Vadim Poliakov
Keyword(s):  
Steady State ◽  
Technological Process ◽  
Mathematical Problem ◽  
Approximate Solutions ◽  
Organic Substrate ◽  
Output Characteristics

The mathematical problem of the steady-state biofiltration of an organic substrate is formulated at two levels  taking into account the limitation and inhibition of the rate of its decomposition. The exact and approximate solutions to the problem of substrate biooxidation in a representative biofilm were obtained and compared using test examples. Based on them an analysis of the technological process in the porous biofilter medium and the output characteristics was carried out.

Sebatian Metoksiaromatik Sebagai Substrat Pertumbuhan dan Pengaruh Enzim Demetilase dalam Acetobacterium Woodii DSM 1030

2012 ◽  
Author(s):  
Mohd. Sahaid Hj. Kalil ◽  
Muhammad Zaki ◽  
Wan Mohtar Wan Yusoff ◽  
Mohammad Ramlan Mohd. Salleh
Keyword(s):  
Growth Rate ◽  
Steady State ◽  
Sole Carbon Source ◽  
Specific Growth ◽  
Chemostat Culture ◽  
Carbon Sources ◽  
Syringic Acid ◽  
Organic Substrate ◽  
Acetobacterium Woodii ◽  
Vanilic Acid

Penyelidikan ini bertujuan untuk menyaring substrat organik bagi untuk penghasilan sel–sel A. woodii teraruh demetilase. Pertumbuhan A. woodii dilakukan dalam medium “Balch” yang mengandungi sumber karbon berbeza dalam keadaan anaerobik. Sebanyak sebelas substrat telah diuji iaitu anisol, 2– dan 3–metoksifenol, asid vanilik, asid siringik, asid 2,3,4–, 2,4,5– dan 3,4,5–trimetoksi benzoik, 2,3,4–, 2,4,5– dan 3,4,5–trimetoksi benzil alkohol. 2–metoksifenol merupakan substrat terbaik untuk pertumbuhan A. woodii pada kadar pertumbuhan spesifik 0.14 j–1. Penghasilan sel–sel teraruh demetilase dilakukan dalam kultur kemostat pada kadar pencairan (D) 0.0j–1. Sel-sel pada keadaan mantap dituai dalam keadaan anaerobik dan dipekatkan sebelum digunakan. Pertumbuhan A. woodii didapati maksimum dengan menggunakan kepekatan 0.62 g/L 2–metoksifenol sebagai sumber karbon tunggal. Tindak balas penyahmetilan oleh sel–sel A. woodii meningkat sebanyak 78% apabila 2–metoksifenol sebanyak 0.31 g/L ditambah dalam medium yang mengandungi fruktosa (1% w/v) semasa kultur kemostat. Kata kunci: tindak balas penyahmetilan; demetilase; sel-sel tertuai; metosiaromatik, Acetobacteriumwoodii The objective of this project was to screen organic substrate suitable for the growth of A. woodii, and as for the production of demethylase. A. woodii was grown in “Balch” medium containing different carbon sources. Eleven substrates were tested including anisole, 2– and 3–methoxyphenol, vanilic acid, syringic acid, 2,3,4–, 2,4,5– and 3,4,5–trimethoxy benzoic acid and 2,3,4–, 2,4,5– and 3,4,5–trimethoxy benzyl alcohol. It was found that 2–methoxyphenol was the best substrate with a specific growth rate of 0.14 h–1. The production of demethylase induced cells was carried out in a chemostat culture at a dilution rate (D) of 0.08 h–1. Cells were harvested at steady state of growth and concentrated before use. Optimal concentration of 2–methoxvphenol as the sole carbon source was 0.62 g/L. Demethylation reaction of 0.31 g/L 2–methoxyphenol by induced culture increases 78% relative to the chemostat culture containing only fructose. Key words: Demethylation reaction; demethylase; harvested cells; methoxyaromatic; Acetobacteriumwoodii

Dynamic Analysis of a Planar SOFC Stack Fuelled by Biogas

2010 ◽  
Author(s):  
A. Salogni ◽  
D. Alberti
Keyword(s):  
Steady State ◽  
Dynamic Behaviour ◽  
Gaseous Mixture ◽  
Control Device ◽  
Organic Substrate ◽  
Pig Manure ◽  
Biological Degradation ◽  
Internal Reforming ◽  
Pure Methane ◽  
Catalytic Burner

This paper analyzes the dynamic behaviour of a 50 kW stack using planar co-flow solid oxide fuel cells with direct internal reforming fuelled by a biologically derived gaseous mixture of methane and carbon dioxide. The system modelled is composed by the SOFC stack, a catalytic burner, the heat recovery system and the control device aimed to keep the air temperature at the stack exit and the fuel utilization near to the set values. The model has been implemented using standard and user-defined components of an a-causal software based on the open-source Modelica modelling language. After a brief introduction to the production of the gaseous fuel derived from the anaerobic digestion of pig manure, data obtained from a case study on a pig farm situated in Lombardia (Italy) are presented, focusing on the yield of methane which can be exploited. The steady-state performance of the SOFC system fuelled by pure methane are compared with those obtained for the biogas working conditions, showing that the stack voltage is affected by greater concentration losses. Then, starting from a steady-state delivered current of 750 mA cm−2, the dynamic behaviour of the system when a load change of −150 mA cm−2 occurs is investigated for both pure methane and biogas fuelling hypothesis. The results of the simulations show that the transient phase is only marginally affected by the composition of the fuel, which causes a delay of about 50 s in the voltage transient. Finally, the effect obtained by imposing a linear variation in the fuel composition, which can be representative of a modification in the biological degradation of the organic substrate within the anaerobic digester, is discussed. After an initial transient, which is comparable with that obtained for a variation in the load current, the SOFC system is capable to restore the initial delivered power, provided that the required amount of fuel can be supplied to the anode.

Thermoplastic Instability for the Transient Contact Problem of Two Sliding Half-Planes

1986 ◽  
Vol 53 (3) ◽  
pp. 565-572 ◽  
Author(s):  
A. Azarkhin ◽  
J. R. Barber
Keyword(s):  
Steady State ◽  
Pressure Distribution ◽  
Half Plane ◽  
Initial Pressure ◽  
Approximate Solutions ◽  
Steady State Solution ◽  
Fourier Integral ◽  
Numerical Results ◽  
Initial Size ◽  
Transient Contact

We study the time dependent problem of a nonconducting half-plane sliding on the surface of a conductor with heat generation at the interface due to friction. The conducting half-plane is slightly rounded to give a Hertzian initial pressure distribution. Relationships are established for temperature and thermoelastic displacements due to a heat input of cosine type through the surface, and then these are used to obtain the solution in the form of a double Fourier integral. Numerical results show that, if the ratio of the initial size of the area of contact to that in the steady state is less than some critical value, the area of contact and the pressure distribution change smoothly toward the steady state solution. Otherwise the area of contact goes through bifurcation. The bifurcation accelerates the process. Numerical results are compared with previous approximate solutions.

Approximate and Analytic Solutions for Deformation of Finite Porous Filters

1997 ◽  
Vol 64 (4) ◽  
pp. 929-934 ◽  
Author(s):  
S. I. Barry ◽  
G. N. Mercer ◽  
C. Zoppou
Keyword(s):  
Fluid Flow ◽  
Steady State ◽  
Porous Material ◽  
Deformation Behavior ◽  
Fluid Velocity ◽  
Approximate Solutions ◽  
Analytic Solutions ◽  
Two Dimensional ◽  
Solid Stress ◽  
Side Walls

The deformation, using linear poroelasticity, of a two-dimensional box of porous material due to fluid flow from a line source is considered as a model of certain filtration processes. Analytical solutions for the steady-state displacement, pressure, and fluid velocity are derived when the side walls of the filter have zero solid stress. A numerical solution for the case where the porous material adheres to the side walls is also found. It will be shown, however, that simpler approximate solutions can be derived which predict the majority of the deformation behavior of the filter.

scholarly journals Unsteady/Steady Hydromagnetic Convective Flow between Two Vertical Walls in the Presence of Variable Thermal Conductivity

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
M. M. Hamza ◽  
I. G. Usman ◽  
A. Sule
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Steady State ◽  
Skin Friction ◽  
Numerical Solutions ◽  
Nonlinear Partial Differential Equations ◽  
Vertical Channel ◽  
Approximate Solutions ◽  
Variable Thermal Conductivity ◽  
Convection Flow

Unsteady as well as steady natural convection flow in a vertical channel in the presence of uniform magnetic field applied normal to the flow region and temperature dependent variable thermal conductivity is studied. The nonlinear partial differential equations governing the flow have been solved numerically using unconditionally stable and convergent semi-implicit finite difference scheme. For steady case, approximate solutions have been derived for velocity, temperature, skin friction, and the rate of heat transfer using perturbation series method. Results of the computations for velocity, temperature, skin friction, and the rate of heat transfer are presented graphically and discussed quantitatively for various parameters embedded in the problem. An excellent agreement was found during the numerical computations between the steady-state approximate solutions and unsteady numerical solutions at steady-state time. In addition, comparison with previously published work is performed and the results agree well.

Analysis and Modeling of the Vortex Amplifier

1969 ◽  
Vol 91 (4) ◽  
pp. 755-763 ◽  
Author(s):  
R. T. Bichara ◽  
P. A. Orner
Keyword(s):  
Experimental Data ◽  
Steady State ◽  
Computer Program ◽  
Flow Regime ◽  
Incompressible Flow ◽  
Digital Computer ◽  
Input Output ◽  
Critical Dimensions ◽  
Fluid Properties ◽  
Output Characteristics

A model has been derived to predict the steady-state input-output characteristics of vortex amplifiers operating in the incompressible flow regime. The model was correlated with experimental data to affect prediction of the influence of the operating fluid properties and the vortex valve critical dimensions on the valve characteristics. The model has been implemented in a digital computer program which includes procedures for the design of vortex valves with specified flow and pressure turndown ratios and the design of vortex amplifiers with proportional (single-valued) characteristics.

scholarly journals SCOPING OF PILOT TESTING OF ENTERPRISE RESOURCE PLANNING

2018 ◽  
Vol 61 (6) ◽  
pp. 478-484 ◽  
Author(s):  
V. V. Zimin ◽  
I. V. Burkova ◽  
V. V. Mit’kov ◽  
A. V. Zimin
Keyword(s):  
Enterprise Resource Planning ◽  
Mathematical Problem ◽  
General Scheme ◽  
Resource Planning ◽  
Approximate Solutions ◽  
Pilot Project ◽  
Probability Of Detection ◽  
Problem Definition ◽  
Network Programming ◽  
Pilot Testing

 Planning of pilot testing is among important problems of creation of Enterprise resource planning. Pilot (experimental) projects are  intended for testing of the main functions of the created system by  limited number of “advanced” users. A key task when planning pilot testing is determination of its volume. If the volume of the pilot  project is small, then essentially important functions of system can be  not checked, and the probability of detection of essential mistakes at  full introduction will be high. If the volume is big, then amount of  works on implementation of the pilot project considerably increases, and there will be no necessary speed and flexibility of testing of the  main functions, because of which pilot testing is organized, and its  efficiency will be close to efficiency of full introduction. The article describes mathematical problem definition of pilot testing scoping which  relies on results of the solution of formation problems of a portfolio  of IT services and creation scheduling of Enterprise resource planning  of the large metallurgical company. The solutions for the considered  task are sets of the services and communications which are subject to  check between them satisfying to the set restriction for volume of the  resources allocated for testing realization, and delivering an optimum  to the set criterion. The procedure of the task solution is based on network programming method which relies on structural and similar network representation of criterion and restrictions. The procedure and an  example of the solution of the studied task in which separate estimated  tasks are solved by method of dichotomizing programming are shown.  The received approximate solutions of an objective can be improved by means of the solution of a dual problem of network programming.  For the purpose of finding of initial task global optimum, the method of  branches and borders can be used in which the criterions of function of  the found approximate solutions are applied as border values. The considered task can be generalized for preferences of the consumers of IT  service concerning need of check of services various communications.  These preferences can be considered by introduction of “scales” of the  corresponding communications. The general scheme of the solution of  a task at the same time doesn’t change.

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