scholarly journals Trichloroethylene adsorption extraction under kinetic conditions by carbon materials in the processes of water treatment of food production

2021 ◽  
Vol 311 ◽  
pp. 10004
Author(s):  
Alena Gorelkina ◽  
Evgeniy Neverov ◽  
Irina Timoshchuk ◽  
Olga Altshuler ◽  
Elena Ostapova

The high level of environmental pollution currently represent a great danger to ecosystems and human health, since a significant part of the generated industrial wastewater is discharged into reservoirs either insufficiently treated or without treatment. In order to reduce the organic substances concentration in the discharged effluents, the use of carbon sorbents is promising. The sorption process requires a comprehensive study, including the process statics, kinetics and dynamics which allows us to establish the features and extraction mechanism. In this paper a model of the studied sorbents granules structure is determined, the mass transfer mechanism in the adaptive control systems is a trichloroethylene (trilene) aqua solution is established, the external mass transfer coefficients which is necessary for engineering calculations are determined. The research results scientific significance lies in the development of the organic substances adsorption theory on the example of trilen by carbon sorbents that differ in the surface structure and properties. The practical significance lies in obtaining kinetic data which is necessary for calculating the wastewater treatment process technological parameters.

2016 ◽  
pp. 26-33
Author(s):  
Irina Timoshchuk ◽  
Irina Timoshchuk

To increase ecological safety of phenol-formaldehyde resins production of the novolac type, the adsorption technology for purification of wastewater containing mainly phenol and formaldehyde was developed. The research of organic substances adsorption (formaldehyde, phenol) from individual aqueous solutions and their mixtures on carbon sorbents grades AG-3, AG-OV-1, SKD-515, BAU, ABG, XAU was conducted, this grades differ in composition, method of producing, structure, and chemical state of the surface. The basic laws, characteristics and mechanism of adsorption of organic substances on activated carbon (AU) were established. The mechanism of mass transfer during adsorption of a mixture of phenol and formaldehyde on the investigated sorbents was showed, and the external mass transfer coefficients were calculated. There was proposed the method of optimization of parameters and continuous adsorption treatment process modes, based on the fundamental external diffusion dynamics adsorption formula using the adsorption constants of the Dubinin-Radushkevich’s equation and kinetic dependencies. The main features of the adsorption dynamics were established, which allowed to determine the duration of column operation, the amount of feed water depending on the throughput rate, the height of the fixed bed and size of the column. According to the results of experimental studies and derivatographic analysis we developed the technology of carbon sorbents regeneration after adsorption of formaldehyde and phenol mixture, which allowed to restore the AC (activated carbon) sorption capacity to 95-98%. On the basis of aggregate balance studies, kinetics and dynamics of adsorption process, optimization of the cleaning regime and the parameters of adsorption column using mathematical modeling, we recommend the technological solution for waste water purification from phenol and formaldehyde, which are formed in the process of phenol-formaldehyde resins of the novolac type production.


2013 ◽  
Vol 19 (4) ◽  
pp. 583-592 ◽  
Author(s):  
Srdjan Kolakovic ◽  
Dragoslav Stefanovic ◽  
Dragan Milicevic ◽  
Slavisa Trajkovic ◽  
Slobodan Milenkovic ◽  
...  

Application of adsorbents based on organo-zeolites has certain advantages over conventional methods applied in food industry wastewater treatment process. The case study presented in this paper examines the possibilities and effects of treatment of dairy industry wastewater by using adsorbents based on organo-zeolites. The obtained results indicate favorable filtration properties of organo-zeolite, their high level of adsorption of organic matter and nitrate nitrogen in the analyzed wastewater. This paper concludes with recommendations of optimal technical and technological parameters for the application of these filters in practice.


2018 ◽  
Vol 170 ◽  
pp. 04005 ◽  
Author(s):  
Tamara Krasnova ◽  
Mikhail Kirsanov ◽  
Oxana Belyaeva ◽  
Irina Timoshchuk

Currently, there is a high level of environmental pollution Urban Territories, which poses a danger to ecosystems and public health, since a significant part of the industrial wastewater generated is discharged into water bodies neither sufficiently purified no without purification. The existing methods for treating effluents containing low concentrations of organic substances are generally quite expensive, long, require significant amounts of reagents or energy-intensive, often accompanied by the formation of secondary pollution and the loss of valuable substances. The scientific significance of the research results lies in the development of the adsorption theory of different nature organic substances by carbon sorbents, which differ in structure and properties of the surface. The values of the adsorption parameters calculated for the investigated active coals calculated from the experimental data can be used in the database of the sorbents' main parameters. The practical importance lies in the choice and recommendations for the practical application of active coals with the best adsorption characteristics, methods for increasing the efficiency of organic components adsorption and obtaining equilibrium data for calculating process parameters of the wastewater treatment process


The paper is a review on the textbook by A. V. Yeremin, «The History of the National Prosecutor’s office» and the anthology «The Prosecutor’s Office of the Russian Empire in the Documents of 1722–1917» (authors: V. V. Lavrov, A. V. Eremin, edited by N. M. Ivanov) published at the St. Petersburg Law Institute (branch) of the University of the Prosecutor’s office of the Russian Federation in 2018. The reviewers emphasize the high relevance and high level of research, their theoretical and practical significance. The textbook and the anthology will help the students increase their legal awareness, expand their horizons.


Author(s):  
G. Variushina

Приводятся сведения об условиях формирования, объемах, химическом составе и свойствах осадков очистных сооружений производственных сточных вод автотранспортных предприятий. Даны примеры технологических решений по обезвоживанию образующихся в процессе очистки шламов. Рассмотрены технологические аспекты процесса интенсификации механического обезвоживания уплотненных осадков с использованием высокомолекулярных полиэлектролитов. Представлены данные лабораторных экспериментов по выбору типа флокулянта, его дозы, технологических параметров процесса, а также результаты определения влажности обезвоженных осадков, полученные на модели барабанного вакуум-фильтра. Приведены примеры эффективных обезвоживающих аппаратов отечественного производства и их технические характеристики, рекомендации и критерии их выбора, а также факторы, оказывающие влияние на эксплуатационные параметры обезвоживающего оборудования. Установлено, что наилучшая обезвоживающая способность барабанных вакуум-фильтров (остаточная влажность шламов от 66 до 83) может быть достигнута при применении катионного флокулянта ВПК-402 для осадков различных производственных цехов автотранспортного предприятия.Information on the conditions of generation, volumes, chemical composition and properties of sludge generated at the industrial wastewater treatment facilities of motor transport enterprises is provided. Examples of process engineering solutions for dewatering sludge generated during the wastewater treatment process are given. The technological aspects of enhancing mechanical dewatering of thickened sludge using high-molecular polyelectrolytes are considered. The data of laboratory experiments on choosing the type of flocculant, its dose, technological parameters of the process, as well as the results of determining the moisture content of dewatered sludge obtained in a model of a drum vacuum filter are presented. Examples of effective domestically produced dewatering apparatus and their technical characteristics, recommendations and criteria for their selection, as well as factors influencing the operational parameters of the dewatering equipment are given. It is found that the highest dewatering capacity of drum vacuum filters (residual sludge moisture content from 66 to 83) can be achieved by using VPK-402 cationic flocculant for processing sludge generated at the workshop premises of a motor transport enterprise.


1998 ◽  
Vol 37 (4-5) ◽  
pp. 139-147 ◽  
Author(s):  
Harald Horn ◽  
Dietmar C. Hempel

The use of microelectrodes in biofilm research allows a better understanding of intrinsic biofilm processes. Little is known about mass transfer and substrate utilization in the boundary layer of biofilm systems. One possible description of mass transfer can be obtained by mass transfer coefficients, both on the basis of the stagnant film theory or with the Sherwood number. This approach is rather formal and not quite correct when the heterogeneity of the biofilm surface structure is taken into account. It could be shown that substrate loading is a major factor in the description of the development of the density. On the other hand, the time axis is an important factor which has to be considered when concentration profiles in biofilm systems are discussed. Finally, hydrodynamic conditions become important for the development of the biofilm surface when the Reynolds number increases above the range of 3000-4000.


1998 ◽  
Vol 38 (6) ◽  
pp. 287-294 ◽  
Author(s):  
Pen-C. Chiang ◽  
Chung-H. Hung ◽  
J. C. Mar ◽  
E. E. Chang

Both Henry's constants and volumetric mass transfer coefficients (KLa) of eight priority chlorinated organic compounds including 1,1-dichloroethene, methylene chloride, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, and 1,4-dichlorobenzene in an air stripping packed column were investigated in this study. The liquid and gas phase EPICS (Equilibrium Partition in Closed System) and direct calculating methods were applied to determine the Henry's constants of VOCs. The interference of co-solute on Henry's constants was also investigated. Experimental results indicated that decrease in Henry's constants of VOCs was observed in the presence of humic acid but no apparent effect on Henry's constants was detected when there was NaCl and surfactant in solution. Four different configurations of packing media including Intalox Saddle, Super Intalox Saddle, Telleret, and Hedgehog made of polypropylene were respectively packed in the air stripping tower and investigated in the study. The dependence of hydraulic loading, air-water ratio, and configurations of packing media on mass transfer coefficients of VOCs was discussed.


Sign in / Sign up

Export Citation Format

Share Document