Gas Hydrate in Water Treatment

Technological, Economic, and Industrial Aspects

Bhajan Lal, Sirisha Nallakukkala

• Publisher: Wiley
• Year: 2022
• Print ISBN:
  9781119866114
• Edition: 1
• eBook ISBN:
  9781119866077
• Topic: Physical Sciences
• Subtopic: Chemistry
• Index: Chemistry

GAS HYDRATE IN WATER TREATMENT

Explores current progress in the expanding field of gas hydrate-based desalination

As potable water shortages continue to affect billions of people worldwide, seawater desalination and wastewater treatment have the potential to meet freshwater demands in the near future. Gas hydrate-based desalination, a process which requires CO2 and water as solvent, has become an increasingly popular approach—desalination with hydrates is environmentally friendly and can produce cheaper desalted water than other existing conventional technologies.

Gas Hydrate in Water Treatment: Technological, Economic, and Industrial Aspects provides detailed, up-to-date reference to the application of gas hydrates in wastewater and seawater desalination treatment. Edited by experienced researchers in the field, this comprehensive volume describes the fundamental aspects of desalination and summarizes the latest research on gas hydrate-based desalination. The authors address a broad range of key topics, including issues related to water scarcity, post-treatment of desalinated water using both conventional and new technologies, hydrate-based desalination methods driven by renewable energy sources, and more.

• Provides thorough coverage of the technological, waste brine management, economic, and renewable energy and remineralization aspects of gas hydrate-based wastewater treatment
• Describes the energetic, economic, and environmental impact of gas hydrate desalination
• Explains the core concepts of gas hydrate-based desalination to help readers evaluate the performance of existing desalination processes
• Discusses the advantages and challenges of hydrate-based water treatment
• Compares conventional and gas hydrate technologies used in water treatment
• Reviews the most recent research in gas hydrate-based desalination

Gas Hydrate in Water Treatment: Technological, Economic, and Industrial Aspects is an essential resource for all academics, researchers, process engineers, designers, industry professionals, and advanced students in the field.

1
Introduction to Desalination

Jesa Singh, Vinayagam Sivabalan and Bhajan Lal

1.1 Coping with Water Scarcity

Climate change and population growth have significantly altered global water resources in the twentieth century and are likely to pose more challenges in the future. One of the greatest of these challenges is freshwater security and equitability. Freshwater is used primarily for sustenance and in various industries that enable today’s high living standards, such as mining, agriculture, and power generation. As evident in Figure 1.1, irrigation consumes the most water among the industrial uses [1]. In the agricultural sector, maintaining an adequate water supply is of foremost importance in ensuring optimal conditions for managing livestock and raising crops, both of which are vital to the wellness of the general population and economies. Lack of freshwater can also affect material and energy-related industries by ultimately decreasing product quality.

Figure 1.1 Freshwater consumption.

Groundwater is an essential source of freshwater, meeting the domestic needs of about half of the global population and more than a third of global consumptive irrigation demand. In the United States (US), groundwater resources provide over fifty billion gallons per day for agricultural needs and drinking water to about half the total population. Nearly all of the US rural population depends on groundwater resources. In areas where surface water such as lakes and rivers are scarce or inaccessible, groundwater also supplies much of the habitant’s hydrologic needs.

Groundwater depletion, defined as long-term water-level declines caused by sustained groundwater pumping, is a key issue associated with groundwater use. Groundwater depletion is significant in most irrigated regions of the world where millions of people reside [2]. Many areas of the United States are experiencing groundwater depletion, which can result in water table lowering, leading to the reduction of freshwater in streams and lakes [2]. While the expansion of groundwater-based irrigation has helped to meet increased food demands, it has resulted in several environmental implications. Groundwater depletion has now become one of the most prominent challenges for food and water security.

Figure 1.2 shows the natural sources of water that make up 71% of our planet [3]. However, out of this 71%, a mere 2.5% is freshwater. From this 2.5%, we only have easy access to approximately 1%, while the remaining 1.5% are trapped in glaciers, ice caps, and deep underground, making it economically unfeasible to access efficiently [4]. The accessibility of freshwater poses a clear problem, as the finite supply may not be enough to upkeep the ever increasing human population.

Figure 1.2 Earth’s freshwater resources.

Water scarcity is a situation where there is not enough water to meet essential needs, like drinking or growing food. Total water consumption has been increasing at a rate of more than twice the rate of population increase in the last century. By 2025, approximately 1.8 billion people will be living in arid regions with absolute water scarcity, while two-thirds of the remaining population will be living under the looming shadow of water scarcity [5]. Figure 1.3 shows the trend in water scarcity around the globe [6].

Figure 1.3 Water scarcity trajectories. Filled graphs represent the absolute population under water scarcity (in billions) while dashed lines represent the population relative to the total regional population [6].

In the event of water scarcity, the most typical symptom is the rise of price in freshwater, due to its inability to meet the required demands and expectations. Compounded with the population growth, it will eventually arrive at a point where there simply is not enough to go around. The general populace tends to not recognize the limits of water supplies, and would rather focus on acquiring additional supplies rather than managing existing supplies. This is repeated in many basins around the world. Because we overbuild and expect too much, we arrive at a situation where there is not enough water to go around. Moreover, when water is reallocated, it tends to meet the needs of the wealthier rather than the poor or marginalized. Cases of successful water management that have effectively tackled water scarcity exist and must be critically examined to prevent the devastating effects of abject resource mismanagement [7].

A process called desalination can mitigate freshwater scarcity by converting seawater, which is unsuitable for either human consumption or industrial and agricultural operations, into freshwater. Various desalination methods have been developed over the last several decades to augment freshwater supplies in arid regions [4] including, multistage flash distillation (MSF), multi-effect distillation (MED), reverse osmosi...

Table of contents

• Cover
• Title page
• Copyright
• Table of Contents
• Preface
• 1 Introduction to Desalination
• 2 Technologies in Desalination
• 3 Prospectives on Gas Hydrates-based Desalination
• 4 Hydrate Promoters in Gas Hydrate-based Desalination
• 5 Modeling of Seawater Desalination by Gas Hydrate Method
• 6 Gas Hydrates in Wastewater Treatment
• 7 Artificial Intelligence in Water Treatment Process Optimization
• 8 Standard Analytical Techniques for Analysis of Wastewater
• 9 Economic Analysis of Desalination Process
• 10 Renewable Energy in Desalination and Hybrid Technologies
• 11 Waste Brine Management
• 12 Post-Treatment of Desalinated Water: Effects and Remedy by Remineralization Methods
• Index
• End User License Agreement