A method for desalination and water remediation by hydrodynamic cavitation

Water is becoming an increasingly valuable commodity, with population growth demanding more and more amounts of this limited resource. Increased efforts are directed toward recycling and remediation, as well as desalination of the large quantities of seawater available. Dr. Bertwin Langenecker was a pioneer in utilizing hydrodynamic cavitation in a variety of applications that would remove dissolved solids from water and other liquids. His combination of intense cavitation using a rotor-stator combination, as well as simultaneously adding an adsorbent, demonstrated impressive results in desalination and waste water remediation. In this presentation, a description will be given of Dr. Langenecker's technology as well as a sampling of some of his most impressive results. Speculations as to why this approach works as well as it does will be presented.

Remediation of textile industrial waste water using a Microbial Fuel Cell (MFC) with 0.4% sodium acetate as substrate is described. In this study, waste water samples from textile industry have been used with varying optical densities of Enterobacter cloacae to assess the bio-remediation efficiency and electrical potential. Textile waste water was found to generate voltage of 502.1 mV which increased to 801.33 mV when pellet of 100 mL Enterobacter cloacae culture was mixed with textile waste water in anodic chamber. Coulombic efficiency of textile waste water alone was 57%, which increased to 80.1% with textile waste water containing 100 mL Enterobacter cloacae pellet. The present study clearly demonstrated that remediation of waste water using MFC technology can be greatly improved by the addition of Enterobacter cloacae as revealed by a decrease in COD value

In recent years, polyelectrolyte-incorporated functional materials have emerged as novel adsorbents for effective remediation of pollutants in water and wastewater. Polyelectrolytes (PEs) are a special class of polymers with long chains of repeating charged moieties. Polyelectrolyte complexes (PECs) are obtained by mixing aqueous solutions of oppositely charged PEs. Herewith, this review discusses recent advances with respect to water and wastewater remediation using PE- and PEC-incorporated adsorbents. The review begins by highlighting some water resources, their pollution sources and available treatment techniques. Next, an overview of PEs and PECs is discussed, highlighting the evolving progress in their processing. Consequently, application of these materials in different facets of water and wastewater remediation, including heavy metal removal, precious metal and rare earth element recovery, desalination, dye and emerging micropollutant removal, are critically reviewed. For water and wastewater remediation, PEs and PECs are mostly applied either in their original forms, as composites or as morphologically-tunable complexes. PECs are deemed superior to other materials owing to their tunability for both cationic and anionic pollutants. Generally, natural and semi-synthetic PEs have been largely applied owing to their low cost, ready availability and eco-friendliness. Except dye removal and desalination of saline water, application of synthetic PEs and PECs is scanty, and hence requires more focus in future research.

Chapter 14 - Biochar technology: A promising approach to mitigate environmental pollutants

Nanoadsorbents for water and wastewater remediation

Fe–Si–B amorphous alloy ribbons (Fe–Si–BAR) are widely investigated recently due to its high efficiency in remediation of wastewater containing azo dyes and other organic pollutants. In this paper, the effects of Fe–Si–BAR on the remediation of water containing high levels of Cu2+ ions were discussed. Results show that the reaction mechanism of Fe–Si–BAR with Cu2+ ions solution is the same as iron powders (FeCP). But the reaction efficiency of Fe–Si–BAR is about 167 and 34 times than that of FeCP for the Cu2+ ions solution of 100 mg/L and 500 mg/L, respectively. Furthermore, the apparent reaction activation energy is calculated to be 18.7 and 19.4 kJ/mol for Fe–Si–BAR and FeCP, indicating that both the reactions of Fe–Si–BAR and FeCP are diffusion-controlled process. Microstructure investigations shown that loose product layer on the surface of the Fe–Si–BAR contribute to the high efficiency of Fe–Si–BAR in remediation of heavy metal-polluted water.

Effects of ultrasonic and hydrodynamic cavitation on the treatment of cork wastewater by flocculation and Fenton processes

Hydrodynamic cavitation for sonochemical effects

Purpose: review of existing technologies and methods of seawater desalination for drinking water supply. Discussion. Based on modern research methods using statistical data and a review of domestic and foreign literature, a review of methods and technologies for desalination and desaltation of highly mineralized natural waters was carried out. The use of sea water for domestic purposes is impossible due to the high content of minerals, however, after desalination, such water can be used for drinking. The choice of technologies and methods of desalination is primarily determined by the quality of source water, as well as the requirements for the quality of treated water, plant productivity and technical and economic calculations. For the drinking water supply purposes, the most efficient and cost-effective method is desalination using reverse osmosis technology, used for both sea and groundwater with high salinity. Reverse osmosis technology has significant advantages over thermal desalination, especially when applied to small-scale plants of small domestic water supply systems. The use of reverse osmosis plants will significantly increase productivity of drinking water output per watt of electricity consumed. Conclusions. The introduction of modern technologies and careful attention to water consumption play a significant role in maintaining water balance in different countries. The most cost-effective and efficient method is seawater desalination using reverse osmosis plants. Despite the fact that water desalination and desaltion plants are very expensive, the conservation of natural waters is a priority nowadays.

Water scarcity is a critical global issue, necessitating efficient water purification and desalination methods. Membrane separation methods are environmentally friendly and consume less energy, making them more economical compared to other desalination and purification methods. This survey explores the application of artificial intelligence (AI) to predict membrane behaviour in water purification and desalination processes. Various AI platforms, including machine learning (ML) and artificial neural networks (ANNs), were utilised to model water flux, predict fouling behaviour, simulate micropollutant dynamics and optimise operational parameters. Specifically, models such as convolutional neural networks (CNNs), recurrent neural networks (RNNs) and support vector machines (SVMs) have demonstrated superior predictive capabilities in these applications. This review studies recent advancements, emphasising the superior predictive capabilities of AI models compared to traditional methods. Key findings include the development of AI models for various membrane separation techniques and the integration of AI concepts such as ML and ANNs to simulate membrane fouling, water flux and micropollutant behaviour, aiming to enhance wastewater treatment and optimise treatment and desalination processes. In conclusion, this review summarised the applications of AI in predicting the behaviour of membranes as well as their strengths, weaknesses and future directions of AI in membranes for water purification and desalination processes.

Cellulose composites tethered with smartness and their application during wastewater remediation

Controlled hydrodynamic cavitation is an energy- and chemicals-saving technology increasingly applied to water sanitation and wastewater remediation via mechanical, oxidative, and thermal degradation of chemical and biological pollutants, including recalcitrant contaminants. Reviewing the advances that have allowed hydrocavitation to emerge as an economically and technically viable environmental technology, we identify the key design parameters that decide its efficacy in degrading biological and chemical contaminants. The ongoing renewable energy boom, lowering the cost of electricity across the world, will only accelerate the adoption of hydrodynamic cavitation as an eminent technology of our common path to sustainability, with energy and clean water access for all.

Controlled hydrodynamic cavitation (HC) has gained the status of the most effective and efficient among green process intensification technologies, due to its cheapness, straightforward scalability, and superior process yields, in a wide area of application fields, such as drinking water disinfection, wastewater remediation, food liquid pasteurization and sterilization, biomass pretreatment, creation of ultra-stable nanoemulsions, and many others. HC has also gained a great reputation as a greener extraction method and for its effectiveness in the intensification of food and pharmaceutical processes. This chapter provides an overview of the technologies based on hydrodynamic cavitation, exploiting the unique capability to generate extremely energy-dense and reactive microenvironments, locally characterized by very high temperatures, intense pressure waves, and hydraulic jets, due to the process of generation, growth, and implosion of vapor bubbles in a liquid, at temperatures below the boiling point. The main methods, techniques, and applications of HC-based technologies are presented, along with the most significant contributions that HC processes can deliver to the food supply chain.

The relevance of the study is due to the fact that the presented object, namely mineral waters in the modern world have a huge potential and play an important role in farming, the coal industry, and in many other fields of life. Mineral water desalination technologies also affect the environment, so there are requirements for improving the methods of recycling brines and regenerative solutions in the desalination of water, due to which it is possible to make a substantial contribution to meeting the requirements of a number of consumers. The purpose of the study is to conduct an experiment, as a result of which recommendations will be made to eliminate errors and improve the quality of various methods of desalination of mineral waters and prevent the problem of disposal of brine, which, when discharged into reservoirs or evaporative sites, substantially worsen the ecological situation. Among the methods used are analytical, experimental, functional, statistical, classification, synthesis. In the course of the study, the features of mineral waters were noted, errors that were made during treatment, and the causes of their occurrence were analysed, and difficulties in the field of coal industry enterprises were analysed: the formation of water, its composition, properties, and degree of impact on the environment. It is important to understand the possibilities of various methods that allow choosing the best technological modes of operation of water treatment processes and successfully solving environmental problems with minimal consumption of reagents, water, and its discharge to the external environment. The practical value lies in the fact that the results obtained can be useful for the industry where mineral resources are extracted and processed, for researchers engaged in the development of new desalination methods, and can substantially reduce production costs and ensure the ecology of the process.

The relevance of the study is due to the fact that the presented object, namely mineral waters in the modern world have a huge potential and play an important role in farming, the coal industry, and in many other fields of life. Mineral water desalination technologies also affect the environment, so there are requirements for improving the methods of recycling brines and regenerative solutions in the desalination of water, due to which it is possible to make a substantial contribution to meeting the requirements of a number of consumers. The purpose of the study is to conduct an experiment, as a result of which recommendations will be made to eliminate errors and improve the quality of various methods of desalination of mineral waters and prevent the problem of disposal of brine, which, when discharged into reservoirs or evaporative sites, substantially worsen the ecological situation. Among the methods used are analytical, experimental, functional, statistical, classification, synthesis. In the course of the study, the features of mineral waters were noted, errors that were made during treatment, and the causes of their occurrence were analysed, and difficulties in the field of coal industry enterprises were analysed: the formation of water, its composition, properties, and degree of impact on the environment. It is important to understand the possibilities of various methods that allow choosing the best technological modes of operation of water treatment processes and successfully solving environmental problems with minimal consumption of reagents, water, and its discharge to the external environment. The practical value lies in the fact that the results obtained can be useful for the industry where mineral resources are extracted and processed, for researchers engaged in the development of new desalination methods, and can substantially reduce production costs and ensure the ecology of the process.