ALGORITHMIC SUPPORT FOR DECISION-MAKING ON THE EFFICIENCY OF OPERATION OF ABSORPTION AND REFRIGERATION PLANTS OF AMMONIA PRODUCTION

The features of the hardware and technological design of the AM-1360 series ammonia synthesis units operating in Ukraine are established, the main of which is the use of heat-using ammonia-water absorption and refrigeration units in the secondary condensation complex. The analysis of the functioning of the absorption and refrigeration units has been carried out. A significant dependence of their efficiency on external disturbances, such as temperature and humidity of atmospheric air, has been established. This causes significant fluctuations in the cooling temperature of the circulating gas in the evaporators of absorption-refrigeration units, which significantly affects the efficiency of ammonia production in general. Based on the results of the analysis of the existing information system, implemented on the basis of the TDC-3000 microprocessor complex, recommendations for its improvement were developed, the presence of which makes it possible to abandon daily analyzes and carry out only control ones to check measuring instruments. Algorithmic support has been developed, implemented in the MATLAB package and tested according to the data of industrial operation of absorption and refrigeration units of the ammonia synthesis unit. This allows the operator, in real production conditions, to obtain operational information on the numerical indicators of the efficiency of operation of absorption and refrigeration units, which characterize their operation to the greatest extent (circulation rate, cooling capacity, circulating gas cooling temperature and thermal coefficient) and make a decision on the possibility of reducing the cooling temperature. of circulation gas in evaporators by changing the frequency of circulation of solutions The created algorithmic software in the MATLAB environment allows embedding a client module, the so-called OPC client. The latter provides technology for free programming of access to current data.

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Main reasons to modify the ecomonitoring system of Novomoskovsk atmosphere relying on modern modeling methods

E3S Web of Conferences ◽

10.1051/e3sconf/201913501085 ◽

2019 ◽

Vol 135 ◽

pp. 01085

Author(s):

Grinyuk Olga ◽

Aleksashina Olga ◽

Arkhipov Alexander ◽

Ganesan Catherine

Keyword(s):

Flow Field ◽

Interpolation Method ◽

Meteorological Data ◽

Air Flow ◽

Movement Control ◽

Weather Conditions ◽

Current Data ◽

Effective Control ◽

Measuring Instruments ◽

Data Adequacy

Novomoskovsk is one of the main centers of chemical industry in central Russia. In 2000 to control and monitor the region air quality and movement the atmosphere ecomonitorin system was created. These systems’ modifying lies in using more sophisticated technology, increasing number of observation stations and automatic sensors that determine harmful impurities. The data adequacy of airspace’s state hinges on the number of these stations and their location. The objective of our study is to estimate the data adequacy relying on modern research methods. The research involved the interpolation method of air movement control over areas which have a mixed landscape because of technology-related accidents. The method consists of 3 main stages: experimental examination of the area’s weather conditions, processing of this data using the method of air flow field recovery, and effective control of the air dynamics at man-made accidents. Air control stations gave the initial measures and current data to develop the method of air flow field recovery on the basis of the noise-resistant interpolation principle. Noise-resistant interpolation admits to errors of measuring instruments, which makes a significant magnitude when estimating meteorological data of the air. The data obtained requires to modify Novomoskovsk ecomonitoring system of the atmosphere.

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Ammonia Synthesis Using Magnetically Induced Reaction

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.334-335.329 ◽

2013 ◽

Vol 334-335 ◽

pp. 329-336 ◽

Cited By ~ 8

Author(s):

Noorhana Yahya ◽

Poppy Puspitasari ◽

Nor Hasifah Noordin

Keyword(s):

Magnetic Field ◽

Catalytic Activity ◽

Applied Magnetic Field ◽

Magnetic Induction ◽

Ammonia Synthesis ◽

High Energy ◽

Ammonia Production ◽

Desorption Process ◽

Capital Intensive ◽

Micro Reactor

Ammonia production is a high energy and capital intensive industry as it requires high temperature (400500°C) and high pressure (150300 bar) for its daily operations. By introducing nanocatalyst with the new concept of micro-reactor with applied magnetic field induction, the catalytic activity can be induced and the output can be enhanced. Magneto-dynamics will be introduced in the ammonia production process in order to replace the concept of thermodynamics in the Haber Bosch process. The nanocatalysts (Y3Fe5O12, Fe2O3, MnO, Mn0.8Zn0.2Fe2O4) have been reduced by using the temperature reduction method (TPR). The Y3Fe5O12(YIG) catalyst with magnetic induction produced242.56µmol/h.g-cat output of ammonia which is 2% much higher than ammonia synthesis without magnetic induction (237.52 µmol/g.h).The ammonia output based on the magnetic induction method at a temperature of 0°C is 242.56µmole/h.g-cat which is 0.90% higher than the synthesis at 25°C temperature (240.4 µmol/g.h). The ammonia output at 0.2Tesla is 249.04 µmole/h.g-cat which is higher 2.6% than the output at 0.1Tesla which is 242.56µmol/g.h. It is proven that the higher the applied magnetic field is, the more effective the catalytic activity will be as a better alignment of the electron spin of the catalyst occurs and enhances the adsorption and desorption process. Y3Fe5O12(YIG) shows the best catalytic reaction followed by Fe2O3(hematite) and MnO (manganese oxide). By this new route, synthesis of ammonia at low temperature is realized and offers ammonia producers an economic advantage compared to the classical routes.

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FORMATION OF IMPURITIES IN SYNTHESIS GAS AT STAGE OF CONVERSION OF CARBON MONOXIDE TO HYDROGEN IN AMMONIA PRODUCTION

IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA ◽

10.6060/ivkkt.20216405.6391 ◽

2021 ◽

Vol 64 (5) ◽

pp. 50-56

Author(s):

Tatyana V. Ivanova ◽

Alexander A. Il'in ◽

Ruslan N. Rumyantsev ◽

Anastasia A. Kournikova ◽

Alexander P. Ilyin

Keyword(s):

Carbon Monoxide ◽

Low Temperature ◽

Gas Phase ◽

Synthesis Gas ◽

Ammonia Synthesis ◽

Conversion Process ◽

Effect Of Temperature ◽

Co2 Removal ◽

Ammonia Production ◽

Medium Temperature

The article analyzes the work of the department for the conversion of carbon monoxide with water vapor to hydrogen as part of the ammonia synthesis unit. The effect of temperature and duration of operation of the medium-temperature conversion catalyst on the technical and technological parameters of the process is shown. The catalytic conversion of carbon monoxide is an important component of the hydrogen production process in the industrial technology of deep processing of natural gas. In modern ammonia synthesis units, the conversion process takes place in two stages: first, at a temperature of 360 – 430 °C on iron-chromium, and then at 190 – 260 °C on a copper-containing catalyst. It was found that along with the main products (H2, CO2), the presence of undesirable impurities of ammonia, amines, alcohols, acetates and formates was detected in the synthesis gas. It is shown that the main by-product at the stage of medium-temperature conversion is ammonia, the content of which in the condensate reaches 80-85%. Methanol is formed as a by-product both at the stage of medium-temperature (9-13%) and low-temperature conversion (87-91%). Most of the methanol generated during the conversion process is condensed with water in separators, while the rest goes to the CO2 removal system. In the separator, where the temperature is 160-162 °C, on average 68% of methanol remains in the gas phase, and in the separator, where deeper gas cooling is applied to 72 °C, about 81% of methanol remains in the condensate. To decrease the methanol content, it is necessary to lower the conversion temperature and increase the gas space velocity. Under the conditions of ammonia production from methanol and ammonia, a mixture of amines of varying degrees of substitution is formed, predominantly methylamine (CH3)NH2 and demytylamine (CH3)2NH2. Moreover, about 35-40% of the formed amines goes into condensate, and most of it remains in the gas phase and goes to the stage of cleaning from CO2. In the production of ammonia, solutions based on potash - K2CO3 are used to clean the converted gas from CO2, which absorb organic impurities, which are formed mainly at the stage of low-temperature conversion. Impurities impair the operation of the purification stage and cause foaming of solutions. One of the reasons for foaming is the presence of organic matter degradation products in the solution.

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Ammonia Plasma-Catalytic Synthesis Using Low Melting Point Alloys

Catalysts ◽

10.3390/catal8100437 ◽

2018 ◽

Vol 8 (10) ◽

pp. 437 ◽

Cited By ~ 11

Author(s):

Javishk Shah ◽

Joshua Harrison ◽

Maria Carreon

Keyword(s):

Energy Cost ◽

Emission Spectroscopy ◽

Ammonia Synthesis ◽

Maximum Energy ◽

Catalytic Synthesis ◽

Energy Yield ◽

Ammonia Production ◽

Inductively Coupled ◽

Bosch Process ◽

Scanning Electron

The Haber-Bosch process has been the commercial benchmark process for ammonia synthesis for more than a century. Plasma-catalytic synthesis for ammonia production is theorized to have a great potential for being a greener alternative to the Haber-Bosch process. However, the underlying reactions for ammonia synthesis still require some detailed study especially for radiofrequency plasmas. Herein, the use of inductively coupled radiofrequency plasma for the synthesis of ammonia when employing Ga, In and their alloys as catalysts is presented. The plasma is characterized using emission spectroscopy and the surface of catalysts using Scanning Electron Microscope. A maximum energy yield of 0.31 g-NH3/kWh and energy cost of 196 MJ/mol is achieved with Ga-In (0.6:0.4 and 0.2:0.8) alloy at 50 W plasma power. Granular nodes are observed on the surface of catalysts indicating the formation of the intermediate GaN.

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The Optimization of an Ammonia Synthesis Reactor Using Genetic Algorithm

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1789 ◽

2009 ◽

Vol 6 (1) ◽

Cited By ~ 3

Author(s):

Mohammad Taghi Sadeghi ◽

Azam Kavianiboroujeni

Keyword(s):

Genetic Algorithm ◽

Ammonia Synthesis ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Ammonia Production ◽

Dimensional Model ◽

Reactor Performance ◽

One Dimensional ◽

Operational Conditions ◽

Quench Temperature

An industrial ammonia synthesis reactor was studied in order to optimize its operational conditions by means of increasing overall ammonia production. A heterogeneous, one-dimensional model and a two-dimensional rigorous model were utilized to evaluate the process behavior. The simulation results of the two models were compared with data from an industrial ammonia plant. The one-dimensional model was found to be adequate for optimization purposes. Applying the Genetic Algorithm (GA) as a powerful method for complex problems, the model was employed to optimize the reactor performance in varying its quench flows. The optimal temperature profile along the fixed bed reactor was studied by changing independent variables including the quench temperature and the quench flow rates. Optimization results show that the optimum quench temperature is about 615°K and that the optimum quench flows can enhance ammonia production rate by 3.3%.

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Synthesis of Ammonia Directly from Air and Water via a Single-Chamber Reactor Using Lanthanum Chromite-Based Composite as an Electrocatalyst

Nano Hybrids and Composites ◽

10.4028/www.scientific.net/nhc.32.35 ◽

2021 ◽

Vol 32 ◽

pp. 35-44

Author(s):

Ibrahim A. Amar ◽

Mohammed M. Ahwidi

Keyword(s):

Noble Metal ◽

Ammonia Synthesis ◽

Direct Synthesis ◽

Formation Rate ◽

Lanthanum Chromite ◽

Ammonia Production ◽

Faradaic Efficiency ◽

Single Chamber ◽

Promising Technology ◽

Ammonia Formation

Carbon-free electrosynthesis of ammonia using water (H2 source) and air (N2 source) is promising technology to reduce the global CO2 emission resulting from the industrial ammonia production process (Haber-Bosch). In this study, electrocatalysis activity of non-noble metal perovskite-based catalyst (La0.75Sr0.25Cr0.5Fe0.5O3-δ-Ce0.8Gd0.18Ca0.02O2-δ, LSCrF-CGDC) for ammonia synthesis directly from air and water was explored. Ammonia was successfully from wet air (3%H2O) synthesized in a single-chamber type reactor. The highest ammonia formation rate and Faradaic efficiency of about 1.94×10-11 mol s-1 cm-2 and 2.01% were achieved at 375 oC and 1.2 V, respectively. The observed ammonia formation rate is higher than reported for an expensive noble metal-based catalyst (Ru/MgO). The obtained results indicated that the direct synthesis of ammonia from air and water is a promising technology for green and sustainable ammonia synthesis.

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Passive Cooling With Phase Change Material Energy Storage

ASME 2013 7th International Conference on Energy Sustainability ◽

10.1115/es2013-18204 ◽

2013 ◽

Author(s):

Peter Omojaro ◽

Cornelia Breitkopf ◽

Simon Omojaro

Keyword(s):

Energy Storage ◽

Phase Change ◽

Energy Saving ◽

Phase Change Material ◽

Cooling System ◽

Average Energy ◽

Cooling Capacity ◽

Sensible Heat ◽

Cooling Temperature ◽

Change Material

A passive induced cooling system using phase change material (PCM) energy storage is presented in this analysis for providing indoor cooling and energy saving. Also, the latent heat performance of the PCM is analyzed. The supplied cooling capacity was evaluated using an indoor cooling temperature performance while the PCM characteristic performance was achieved by relating the applications sensible heat ratio efficiency to the charging and discharging effectiveness of the PCM. This is carried out for an office building in a warm humid climate. Obtained result delivered 24.54 % of the required indoor cooling load for 24°C indoor cooling temperature. Moreover, delivered indoor cooling capacity increased at constant increasing mean indoor temperature and PCM melting temperatures. Application sensible heat ratio efficiency was 77.66 % and average energy saving of 37.77 % in total energy operation cost was obtained. A CO2 emission reduction of 0.071 tons can also be achieved by the system.

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Desiccant Degradation in Desiccant Cooling Systems: A System Study

Journal of Solar Energy Engineering ◽

10.1115/1.2930056 ◽

1993 ◽

Vol 115 (4) ◽

pp. 237-240 ◽

Cited By ~ 5

Author(s):

A. A. Pesaran

Keyword(s):

Cooling System ◽

Cooling Capacity ◽

Coefficient Of Performance ◽

Thermal Coefficient ◽

Ventilation Mode ◽

Worst Case ◽

Cooling Systems ◽

Degradation Data ◽

Percent Loss ◽

The Impact

We predicted the impact of desiccant degradation on the performance of an open-cycle desiccant cooling system in ventilation mode using the degradation data on silica gel obtained from a previous study. The degradation data were based on thermal cycling desiccant samples and exposing them to ambient or contaminated air. Depending on the degree of desiccant degradation, the decrease in the thermal coefficient of performance (COP) and the cooling capacity of the system for low-temperature regeneration was 10 percent to 35 percent. The 35 percent loss occurred based on the worst-case desiccant degradation scenario. Under more realistic conditions the loss in system performance is expected to be lower.

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Towards understanding of electrolyte degradation in lithium-mediated non-aqueous electrochemical ammonia synthesis with gas chromatography-mass spectrometry

RSC Advances ◽

10.1039/d1ra05963g ◽

2021 ◽

Vol 11 (50) ◽

pp. 31487-31498

Author(s):

Rokas Sažinas ◽

Suzanne Zamany Andersen ◽

Katja Li ◽

Mattia Saccoccio ◽

Kevin Krempl ◽

...

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Ammonia Synthesis ◽

Gas Chromatography Mass Spectrometry ◽

Ammonia Production ◽

Organic Electrolytes ◽

Electrochemical Systems ◽

Chromatography Mass Spectrometry ◽

The Stability

Lithium-mediated non-aqueous electrochemical ammonia synthesis (LiMEAS) as an efficient and green ammonia production way was studied by GCMS in different organic electrolytes to evaluate the stability of electrochemical systems.

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