The Optimalization of Heating Steam Pressure on Thermal Effectiveness of Drying Cylinders

2011 ◽  
Vol 58 (1) ◽  
Author(s):  
Włodzimierz Kawka ◽  
Mariusz Reczulski
Keyword(s):  
Steam Pressure ◽  
Heating Steam

scholarly journals Application of a Two-Stage Steam Jet Injector Unit for Latent Heat Recovery of a Marine Steam Turbine Propulsion Plant

2021 ◽  
Vol 11 (12) ◽  
pp. 5511
Author(s):  
Szymon Grzesiak ◽  
Andrzej Adamkiewicz
Keyword(s):  
Steam Turbine ◽  
Steam Pressure ◽  
Relative Increase ◽  
Parameters Optimization ◽  
Feed Water ◽  
Water Heating ◽  
Two Stage ◽  
Heating Systems ◽  
Heating Steam ◽  
Numerical Research

The paper presents the results of the numerical research of the steam jet injector applications for the regenerative feed water heating systems of marine steam turbine propulsion plants. The analysis shows that the use of a single injector for a single heat exchanger results in a relative increase in the thermal efficiency of the plant by 0.6–0.9%. The analysis also indicates the legitimacy of the usage of multistage feed water heating systems, which would enable the operating parameters optimization of the injectors. The obtained steam pressure up to the value of 1.8 barA allows for the heating of the feed water up to 110 °C. For higher degrees of feed water heating in the heat exchangers, it is necessary to supply heating steam of higher pressure. Therefore, the usage of two-stage steam jet injector units was considered advisable for the analyses.

scholarly journals Improving the massecuite crystallization in sugar production

2021 ◽  
Vol 83 (1) ◽  
pp. 86-93
Author(s):  
N. G. Kulneva ◽  
V. A. Fedoruk ◽  
N. A. Matvienko ◽  
E. M. Ponomareva
Keyword(s):  
Operating Mode ◽  
Steam Pressure ◽  
Small Temperature ◽  
Steam Consumption ◽  
Heating Chamber ◽  
Heating Steam ◽  
Vacuum Apparatus ◽  
Continuous Vacuum ◽  
Product Department ◽  
Entire Apparatus

The article discusses the concepts of continuous vacuum apparatus operation: vertical VKT (VKT – Verdampfungs-Kristallisations-Turm) and horizontal cascade of VKH vacuum apparatus (VKH —horizontal vacuum pan) from BMA (Germany). The advantages and features of the vertical continuous vacuum apparatus VKT are shown, as well as the possibilities for increasing the efficiency of the product department of sugar factories. Thanks to the special design of the crystallization chambers, the low massecuite level above the heating chamber and the use of mechanical stirrers in each chamber, the VKT apparatus can operate without difficulty with a very small temperature difference between heating steam and massecuite, as well as with an absolute heating steam pressure well below 1 bar. With optimal use of VKT vacuum apparatus, a variety of energy-saving schemes can be implemented, for example, double-effect evaporation in the crystallization section. Part of the secondary crystallization steam is used to heat one of the VKT units, which saves the heating steam of the evaporator unit used for this purpose. With an increase in the productivity of the sugar factory, it is possible to quickly equip the VKT apparatus with an additional chamber. The device works continuously throughout the season, especially with products with massecuite purity of more than 94%. The chambers are cleaned without stopping the entire apparatus. The boiling of massecuite of all stages of crystallization in VKT devices ensures a uniform operating mode of the food compartment, allows to achieve an increase in sugar yield and helps to reduce steam consumption at the plant.

Evaporation performance: present and future in Colombian cane sugar factories

2017 ◽  
pp. 264-269
Author(s):  
D.F. Cobo ◽  
J.G. Rodriguez ◽  
A.F. Ospina ◽  
A.L. Gomez ◽  
N.J. Gil
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Performance Index ◽  
Steam Pressure ◽  
Cane Sugar ◽  
Heat Transfer Area ◽  
Improve Performance ◽  
Heating Steam ◽  
New Guidelines

Evaporation performance is usually affected by internal and external factors such as sugarcane quality, juice conditioning, exhaust steam availability, juice flow variation, heat transfer area available, type of evaporator, and geometric relationships. These factors influence the evaporation rate and cleaning frequency. An integral strategy to improve performance was proposed, including technological changes (falling-film evaporators) evaluated by simulation, on-line performance index (evaporation performance index, EPI), and new guidelines for the evaporation station configuration. EPI, proposed by Cenicaña (Colombia), is defined as the product of RDS (refractometric dry substance content) difference and juice flow divided by the product of heating steam pressure and heat transfer area. The results show that it is possible to improve performance of the third effects by extending the calandria tubes in Robert-type evaporators; this improves the heat transfer coefficient by 15–30%. In most cases, increasing juice flow velocity in evaporator tubes will increase the overall heat transfer coefficient. The use of longer tubes should be considered when modifications in evaporation stations are required. In addition, the application of EPI as a tool to assess the performance in the evaporation train and make decisions regarding the cleaning schedule was validated.

scholarly journals TECHNOLOGY OF CYCLIC DISTILLATION IN ALCOHOL PRODUCTION

2019 ◽  
Vol 13 (4) ◽  
Author(s):  
Y. Buliy ◽  
P. Shiyan ◽  
A. Kuts ◽  
I. Melnik
Keyword(s):  
Mass Transfer ◽  
Impurity Concentration ◽  
Steam Pressure ◽  
Hydrodynamic Mode ◽  
Specific Flow ◽  
Vapor Velocity ◽  
Alcohol Production ◽  
Cyclic Mode ◽  
Fusel Alcohols ◽  
Heating Steam

Alternate changing of the steaming periods and liquid overflow allows to intensify mass transfer between liquid and steam and to reduce the specific consumption of heating steam in the process of separation of multicomponent mixtures. Known methods and models have not found widespread practical use due to the lack of mass transfer in the steam period, fluctuations in steam pressure in the collector, the complexity of constructive solutions to ensure cyclic mode, etc. The authors propose a technology for rectification, which involves the cyclic motion of the liquid without interrupting of the supply of heating steam and the construction of a rectification column for its implementation. The purpose of the work was to research the effectiveness of the proposed technology in the process of rectification of alcohol-containing fractions and to establish the specific flow rate of steam in the impurity concentration column. To ensure a cyclic mode, the column was equipped with movable liquid transfer devices connected to actuating mechanismes, which acted according to the controller program, and perforated (scale-shaped) trays. The primary task was to determine the hydrodynamic mode of operation of the contact devices - the lower and upper the critical vapor velocity of at which the liquid is retained on the plates and there is its entrainment. It is established that the vapor velocity in the free section of the column can reach 1.2 m/s or more, and in the openings of the scales must exceed the first critical velocity of 6.5-7.5 m/s. The weeping of the tray occurs at the vapor velocity in the holes of 1.5-1 m/s. The investigations were carried out in the production conditions of the Chudniv branch of SE “Zhytomyr liquor producer ”. It is experimentally proved that in the process of rectification of alcohol-containing fractions, the main impurities are removed completely, the degree of extraction of higher fusel alcohols is increased by 38%, methanol - by 15.6 %, the multiplicity of concentration of the main impurities is increased by 25 %, the higher alcohols - by 40 %, methanol – by 34 %, acrolein – by 36 %. The costs of heating steam are reduced by 30 % compared to typical installations and do not exceed 13 kg/dal of absolute alcohol introduced with feed. Exempted from the key impurities the bottom liquid of the impurity concentration column should be used for hydroselection in the purifying column.

Efficiency of two-stage heating of water on CHP plant with turbines of type T-250/300-240

2019 ◽  
Vol 12 (3) ◽  
pp. 213-219
Author(s):  
E. T. Ilin ◽  
S. P. Pechenkin ◽  
A. V. Svetushkov ◽  
J. A. Kozlova
Keyword(s):  
Transition Period ◽  
Steam Pressure ◽  
Low Pressure ◽  
Heat Extraction ◽  
Two Stage ◽  
Permissible Level ◽  
Lower Heat ◽  
Operational Modes ◽  
Extraction Section ◽  
Supply Water

During non-heating and transition period, most of cogeneration turbines operate with a lower heat extraction section actuated only due to a number of restrictions on the maximum and minimum pressure levels in the upper and lower heat extraction sections at operation of the turbine. For turbines of model T-250/300-240, the minimum permissible level of steam pressure in the upper heat extraction section, according to manufacturer data, is set to 0.06 MPa. During the non-heating and transition period, the supply water temperature is usually set in the range of 70–75°С. In order to maintain that temperature of supply water, the steam pressure in the upper heat extraction section should be below the minimum permissible level. As a result, the turbine operates with only the low-pressure heat extraction section actuated, which ensures operation without restrictions, but with a lower efficiency. The authors have introduced a set of measures, which enable to avoid those restrictions and implement two-stage heating of supply water. In this case, on connection of the upper heating extraction section, the pressure in the same is maintained at the minimum permissible level. Heat output characteristics are provided by having some of supply water delivered bypassing the group of network heaters. This operational mode enables to increase the turbine actual heat drop, to reduce the cooling steam flow into the low-pressure section and, accordingly, into the condenser, and to reduce temperature drops in network water heaters. Results of the research of operational modes for turbines of type T-250/300-240 in the non-heating and transition period with one and two-stage heating are provided. The economic efficiency of proposed operational modes was researched, which shows the effectiveness of those modes during non-heating and transition period. The limits of the efficiency of using these modes are determined.

Considerations about mass and energy flow in discontinuous evaporating crystallizers

2016 ◽  
pp. 514-516
Author(s):  
Martin Bruhns
Keyword(s):  
Energy Flow ◽  
Static Pressure ◽  
Bubble Formation ◽  
Boiling Temperature ◽  
Vapor Bubbles ◽  
Local Pressure ◽  
Heating Steam ◽  
Flow Changes ◽  
Local Superheating ◽  
Local Supersaturation

The massecuite circulates in a loop within the evaporating crystallizing vessel. The massecuite flows upwards through the heating tubes. In the room above the calandria the massecuite flow changes its direction to radial inwards and then to vertical downwards. An impeller in the central tube forces the circulation. Below the calandria the main direction of flow is radially outwards until threads of the massecuite stream enter the heating tubes in upwards direction. Within the tubes heat is transferred to the massecuite. At low temperature differences between heating steam and massecuite and higher levels of the massecuite in the crystallizer vapor bubbles are not found in the tubes. Vapor bubbles can be formed at a massecuite level in the crystallizer where the temperature of the massecuite is higher than the local boiling temperature of water, which depends on the local pressure (including the static pressure of the massecuite at this point) and the boiling point elevation of the mother liquor. The surface tension of the liquid is a resistance against the bubble formation, which has to be overcome by the local superheating i.e. the part of the enthalpy of the massecuite exceeding the local boiling temperature. The formation and the flow of the bubbles change the density of the massecuite/bubbles mixture and has an influence on the massecuite flow. The formation of a vapour bubble is connected with a local drop of the massecuite temperature which changes the local supersaturation. Today the heat transfer into the magma is quite well known but the process of bubble formation is quite unknown. Some basic considerations about the formation of bubbles and its influence on local supersaturation based on calculation of heat and mass balances and models of bubble formation are be given and discussed. Experiments for basic investigations are proposed.

Proposal for modernization of Robert evaporators

2020 ◽  
pp. 51-54
Author(s):  
Hans Joachim Praus
Keyword(s):  
Falling Film ◽  
Film Evaporator ◽  
Heating Steam

It is proposed to convert existing Robert evaporators into Trebor evaporators. Trebor evaporators work as falling film evaporators with the well-known thermal and technological advantages. When converting a Robert evaporator into a Trebor evaporator, the heating steam inlet and the vapour outlet as well as the condensate drain remain in their original positions. If necessary, the positions of the juice inlet and outlet nozzles are changed, and two additional nozzles and a circulation juice pump are required. These changes are cheaper than installing a new falling film evaporator.

Steam pressure conductivity and stability of H3O+-β″/β-Al2O3 ceramic electrolytes

1990 ◽  
Vol 38 (3-4) ◽  
pp. 251-254 ◽  
Author(s):  
C KUO ◽  
A TAN ◽  
P SARKAR ◽  
P NICHOLSON
Keyword(s):  
Steam Pressure ◽  
Al2o3 Ceramic ◽  
Ceramic Electrolytes

Optimization of a Sintering Waste Heat Power Unit

2014 ◽  
Vol 1008-1009 ◽  
pp. 897-900
Author(s):  
Xue Min Gong ◽  
Jiu Lin Yang ◽  
Chen Wang
Keyword(s):  
Power Generation ◽  
Power Unit ◽  
Waste Heat ◽  
Steam Pressure ◽  
Operating Conditions ◽  
Parameters Optimization ◽  
Heat Power ◽  
Optimal Value ◽  
Generation Capacity ◽  
Main Steam

An optimization was performed for a sintering waste heat power unit with all data obtained in the site and under the unit normal operating conditions. The physical and mathematical model for the process of cooling and generation is established, which makes the net power generation as an objective function of the cooling machine imported ventilation, the thickness of sinter and the main steam pressure. Optimizing for single parameter, we found that each parameter had an optimal value for the system. In order to further optimize the system's operating parameters, genetic algorithm was used to make the combinatorial optimization of the three parameters. Optimization results show that power generation capacity per ton is increased by13.10%, and net power generation is increased by 16.17%. The optimization is instructive to the operation of sintering waste heat power unit.

Sign in / Sign up

Export Citation Format

Share Document