scholarly journals THE USE OF FLOTATION METHOD FOR PURIFICATION OF WASTEWATERS CONTAMINATED WITH OIL PRODUCTS

2021 ◽  
Vol 29 (1) ◽  
pp. 11-19
Author(s):  
Mariia Maksymiuk ◽  
Tetiana Kravchuk ◽  
Olha Titova ◽  
Olena Kosenko ◽  
Olena Spaska
Keyword(s):  
Wastewater Treatment ◽  
Toxic Substances ◽  
Flotation Reagents ◽  
Dispersed Particles ◽  
Living Things ◽  
Purification Time ◽  
Highly Dispersed ◽  
Flotation Method ◽  
The Impact ◽  
Methods Of Treatment

Industrial and natural wastewater is one of the factors of environmental pollution, in particular, its water basin. Among others, fuel and oil pollutants are toxic substances that cause significant harm to all living things. It is necessary to create technologies using effective methods of wastewater treatment to solve such problems. It is possible to properly select and effectively use methods of treatment taking into account the nature, condition and concentration of contaminants in wastewater. These are the issues addressed in this article. Particular attention is paid to the use of flotation as a method of purification of stable highly dispersed emulsified wastewater containing oil or fuel contaminants in the technology of this type wastewater treatment. The main objectives of the study were to evaluate the impact of parameters and flotation reagents on the efficiency of the process of purification of stable highly dispersed emulsified wastewater. Flotation of these wastewaters was carried out on a laboratory flotation installation of pneumatic type and compared with the process of wastewater settling over time. Studies have shown that for stable emulsified wastewater containing oil or fuel contaminants with a low content of highly dispersed particles of inorganic nature or a stabilizer is present in them, it is advisable to use the flotation method with flotation units of pneumatic type. Analysing the results, it should be noted that the flotation method significantly reduces the purification time of highly dispersed emulsified wastewater from 3-5 hours of their settling in settling tanks-oil traps up to 10-20 minutes by the method of pneumatic flotation, while the degree of wastewater treatment increases in at least 1.5 - 2 times depending on the presence of fuel or oil contaminants in wastewater. If the wastewater contains a stabilizer, such as a surfactant, it can be used as an effective flotation reagent in the purification of this type of wastewater by flotation, which is not suitable for the settling process.

scholarly journals Evaluation of the biogas potential of a lignocellulosic residue

2021 ◽  
Author(s):  
Nardjes Guendouz ◽  
Hynda Rezzaz-Yazid ◽  
Salima Laib ◽  
Zahra Sadaoui
Keyword(s):  
Wastewater Treatment ◽  
Biological Process ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Cattle Manure ◽  
Toxic Substances ◽  
Lignocellulosic Materials ◽  
Ammoniacal Nitrogen ◽  
Lignocellulosic Residue ◽  
The Impact

Abstract Anaerobic digestion (AD) or methanization is a biological process that allows the treatment of organic wastes and the production of renewable energy as biogas. This research describes assessment and optimization of dates pedicels rich in organic components under the conditions of mesophiles in co-digestion in association with the cattle manure and sludge of the wastewater treatment plant (WWTP). To realize this objectives, we investigated the impact of substrate load (date pedicel) on the co-digestion anaerobic of date pedicels and the sludge in wastewater treatment plants. The different parameters of the digester stability such as the pH, VFA, CAT, ammoniacal nitrogen, and the volume of biogas produced were followed. The results show that by increasing the mass of the pedicels and therefore the percentage of the substrate in the reactor, from 0.5 to 1% (W/V), the volume of produced biogas increases by five times. However, an increase in the percentage of the substrate introduced into the digester from 1 to 2% resulted in a slight decrease in the volume of biogas produced. The use of fresh cattle manure as inoculum shown a significant improvement (40%) in the production of biogas, which can be attributed to the nature of the inoculum. Indeed, cattle manure fresh is more adapted for the fermentation of lignocellulosic materials unlike sludge of wastewater treatment plants which may contain toxic substances that limit their use in AD.

scholarly journals The Impact of an Ultrasonic Field on the Efficiency of Coke Wastewater Treatment in a Sequencing Batch Reactor

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 963
Author(s):  
Anna Kwarciak-Kozłowska ◽  
Małgorzata Worwąg
Keyword(s):  
Wastewater Treatment ◽  
Sequencing Batch Reactor ◽  
Treatment Process ◽  
Batch Reactor ◽  
Oxygen Demand ◽  
Ultrasonic Field ◽  
Toxic Substances ◽  
Coke Wastewater ◽  
Biological Methods ◽  
The Impact

The growing production of coke and, consequently, coke wastewater is a significant problem for the environment. Coke wastewater, because it contains high amounts of toxic substances, is classified as an extremely hazardous industrial wastewater. The treatment of such wastewater requires a combination of advanced physicochemical and biological methods. The aim of the research was to investigate the effectiveness of the application of the ultrasonic disintegration of coke wastewater in a sequencing batch reactor (SBR). The tests were conducted in two stages, wherein the first stage involved determining the most favorable sonication conditions, that is, time and amplitude. The authors used the following amplitudes: 31 µm; 61.5 µm; 92 µm; 123 µm and times: 120 s; 240 s; 480 s; 960 s. The second stage focused on treating coke wastewater in SBRs (Reactor A—a proportion of coke wastewater in the mixture: 5%, 10%, and 20%; reactor B—sonicated coke wastewater, proportion in mixture: 5%, 10%, 20%). The efficiency of the treatment process was determined based on the rate of removal of selected parameters: chemical oxygen demand (COD), total organic carbon (TOC), inorganic carbon (IC), ammoniacal nitrogen (N-NH4), total nitrogen (TN), the course of pH changes. The study revealed that sonication of coke wastewater increased biodegradability and reduced its toxicity. The use of the preliminary sonication of coke wastewater before biological treatment improved the degree of removal of the tested parameters by approximately 10%. The volumetric ratio of coke wastewater in the mixture had the greatest impact on the obtained results. The use of an ultrasound field allows the treatment process to be executed with a coke wastewater addition exceeding 10%. In addition, it was found that in order to increase the coke wastewater treatment efficiency, one should optimize individual phases in the SBR and the pollution load.

U.S. Regulatory Approaches: A Critical Appraisal

1992 ◽  
Vol 25 (3) ◽  
pp. 13-21
Author(s):  
R. L. Williamson
Keyword(s):  
Decision Making ◽  
Command And Control ◽  
Regulatory System ◽  
Federal Agencies ◽  
Toxic Substances ◽  
Use Of Technology ◽  
Treatment Technologies ◽  
New Treatment ◽  
And Control ◽  
The Impact

The American approach to environmental regulation is characterized by fragmentation of responsibilities, primary reliance on command and control regulations, extraordinary complexity, a preference for identifiable standards, and heavy resort to litigation. This system has provided important benefits, including significant reduction of environmental contamination, substantial use of science in decision-making, broad participatory rights, and the stimulation of new treatment technologies. However, these gains have been achieved at excessive cost. Too much reliance is placed on command and control methods and especially on technology-based standards. There is too much resort to litigation, and inadequate input from science. Participatory rights are being undermined, and there is a poor allocation of decision-making among the federal agencies and the states. Over-regulation sometimes leads to under-regulation, and insufficient attention is given to the impact on small entities. The responsibility for these difficulties rests with everyone, including the federal agencies, the Congress, the general public and the courts. Changes in the regulatory system are needed. We should abandon the use of technology-based standards to control toxic substances under the Clean Water Act in favor of strong health- and environmentally based standards, coupled with taxes on toxic substances in wastewater.

Evaluation of Toxicity in Receiving Streams

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2357-2360
Author(s):  
J. Zagorc-Koncan ◽  
M. Dular
Keyword(s):  
Dissolved Oxygen ◽  
Toxic Substances ◽  
Toxicity Evaluation ◽  
Copper Cyanide ◽  
Polluted River ◽  
Design Information ◽  
Point Of Entry ◽  
Receiving Stream ◽  
The Impact

A laboratory river model for the study of self-purification inhibition in a stream containing toxic substances is presented. It enables an engineering - technological prediction of the impact of toxic substances or wastewaters on dissolved oxygen (DO) profile in an organically polluted river downstream from the point of entry of toxic effluent thus providing rapidly and inexpensively significant design information to an environmental scientist or engineer. The method was applied to the toxicity evaluation of wastewaters from electroplating industry. The effects of copper, cyanide (representing two significant constituents of this type of wastewaters) and wastewater from electroplating industry on the biodegradation of organic municipal pollution in receiving stream were evaluated experimentally.

Optimisation and control of the inflow to a wastewater treatment plant using integrated modelling tools

1998 ◽  
Vol 37 (1) ◽  
pp. 347-354 ◽  
Author(s):  
Ole Mark ◽  
Claes Hernebring ◽  
Peter Magnusson
Keyword(s):  
Wastewater Treatment ◽  
Real Time ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Pilot Project ◽  
Integrated Modelling ◽  
Real Time Control ◽  
Sewer System ◽  
Time Control ◽  
The Impact

The present paper describes the Helsingborg Pilot Project, a part of the Technology Validation Project: “Integrated Wastewater” (TVP) under the EU Innovation Programme. The objective of the Helsingborg Pilot Project is to demonstrate implementation of integrated tools for the simulation of the sewer system and the wastewater treatment plant (WWTP), both in the analyses and the operational phases. The paper deals with the programme for investigating the impact of real time control (RTC) on the performance of the sewer system and wastewater treatment plant. As the project still is in a very early phase, this paper focuses on the modelling of the transport of pollutants and the evaluation of the effect on the sediment deposition pattern from the implementation of real time control in the sewer system.

scholarly journals Tanning Wastewater Treatment by Ultrafiltration: Process Efficiency and Fouling Behavior

Membranes ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 461
Author(s):  
Fu Yang ◽  
Zhengkun Huang ◽  
Jun Huang ◽  
Chongde Wu ◽  
Rongqing Zhou ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Shear Rate ◽  
Membrane Surface ◽  
Filtration Efficiency ◽  
Operating Conditions ◽  
Process Efficiency ◽  
Transmembrane Pressure ◽  
Leather Industry ◽  
Pore Blocking ◽  
The Impact

Ultrafiltration is a promising, environment-friendly alternative to the current physicochemical-based tannery wastewater treatment. In this work, ultrafiltration was employed to treat the tanning wastewater as an upstream process of the Zero Liquid Discharge (ZLD) system in the leather industry. The filtration efficiency and fouling behaviors were analyzed to assess the impact of membrane material and operating conditions (shear rate on the membrane surface and transmembrane pressure). The models of resistance-in-series, fouling propensity, and pore blocking were used to provide a comprehensive analysis of such a process. The results show that the process efficiency is strongly dependent on the operating conditions, while the membranes of either PES or PVDF showed similar filtration performance and fouling behavior. Reversible resistance was the main obstacle for such process. Cake formation was the main pore blocking mechanism during such process, which was independent on the operating conditions and membrane materials. The increase in shear rate significantly increased the steady-state permeation flux, thus, the filtration efficiency was improved, which resulted from both the reduction in reversible resistance and the slow-down of fouling layer accumulate rate. This is the first time that the fouling behaviors of tanning wastewater ultrafiltration were comprehensively evaluated, thus providing crucial guidance for further scientific investigation and industrial application.

scholarly journals Compulsive Buying in Adolescents. The Impact of Gender and Alcohol and Cannabis Use

2021 ◽  
Vol 13 (7) ◽  
pp. 3982
Author(s):  
Gloria Pérez de Albéniz-Garrote ◽  
Maria Begoña Medina-Gómez ◽  
Cristina Buedo-Guirado
Keyword(s):  
Compulsive Buying ◽  
Cannabis Use ◽  
Descriptive Statistics ◽  
Cluster Sampling ◽  
Toxic Substances ◽  
Higher Alcohol ◽  
Random Cluster ◽  
Prevention Programmes ◽  
The Impact ◽  
Buying In

The purpose of this study to analyse whether compulsive buying in teenagers is related to gender and alcohol and cannabis use in a sample of 573 students aged 14–17 from secondary education schools in Burgos (Spain) (M = 15.65; SD = 1.04). Random cluster sampling was performed to select the sample. The Compulsive Buying Questionnaire was used together with two extra promts: ‘Indicate how much alcohol you consume’ and ‘Indicate how much cannabis you take’. Descriptive statistics were used in data analysis, while MANOVA was used to study gender differences in alcohol and cannabis use, compulsive buying and their interaction. The results show higher scores for female compulsive buyers than for men, higher scores for alcohol and cannabis users’ compulsive buying than for non-users, respectively, and higher scores for female users than for male users. A certain interaction was also observed between alcohol and cannabis use. A higher alcohol consumption entailed a higher score in compulsive buying, with cannabis users who did not consume alcohol obtaining the highest scores. Thus, prevention programmes should consider teenagers’ gender and the risk of taking toxic substances.

scholarly journals Sexuality and Affection in the Time of Technological Innovation: Artificial Partners in the Japanese Context

Religions ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 296
Author(s):  
Beatriz Yumi Aoki ◽  
Takeshi Kimura
Keyword(s):  
18Th Century ◽  
Human Life ◽  
Human Sexuality ◽  
Sexual Intimacy ◽  
Ancient History ◽  
Human Relationships ◽  
Living Things ◽  
Long Time ◽  
History Of ◽  
The Impact

Recent years have witnessed an increase in the number of academic studies on the impact of technological advancements on human life, including possible transformations and changes in human sexuality following the development of sex-related devices, such as sex robots. In this context, terms such as posthuman sexuality, digisexuality, and techno-sexuality have emerged, signaling possible new understandings of sexual, intimacy, and emotional practices. It is important to note that ancient history shows that humankind has for a long time been fascinated with their relationship to non-living things, mostly human-like figures, such as dolls. The Ningyo (人形, the Japanese term for doll) has a long history of usage, and has deep religious and animistic significance in the Japanese context—there are records of sexual use as early as the 18th century. With this context in mind, this paper focuses on three Japanese examples, aiming to shine a light on beyond-human relationships, which include a Japanese man’s marriage to a digital character, sex dolls, and communicative robots, from both a sexual and emotional perspective. In a new horizon of sexual and romantic possibilities, how will humans respond, and what can emerge from these interactions?

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