We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is Foam Separation?

By Paul Reed
Updated May 17, 2024
Our promise to you
About Mechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At About Mechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Foam separation is a process of removing a component of a liquid mixture using a bubbled gas and a surfactant to collect the material. A surfactant is a chemical that helps produce foam without chemically reacting with the solution. Many materials can be removed from liquids using foam separation methods, including precious metals, proteins, and impurities from water.

Another term for foam separation is adsorptive bubble separation. Adsorption means that a material is deposited on the surface of the foam without a chemical reaction having occurred. The foam has a surface tension, and in some cases a molecular polarity, that attracts the desired material onto the foam surface.

There are a number of chemical methods for extracting gold from ore, but many of them include toxic chemicals and waste products. Gold can be extracted from a liquid mixture using air or nitrogen gas and a foam-producing surfactant. The foam exiting the equipment is enriched in gold, which can then be separated by centrifuges that spin out the gold and remove the foam.

Separation of proteins and oils can be accomplished with foam separation equipment. The surfactants attract the desired product onto the foam interface by preferring the organic or oil molecules to water molecules. Foam systems may use non-reactive nitrogen gas rather than compressed air to prevent any oxidation reactions of air with the desired materials.

Wastewater treatment systems often use foam separation steps to remove solids from the water stream. Larger solids can be removed by gravity or centrifuge operations, but fine solids must also be removed to meet treated water standards. Air can be bubbled along with a surfactant to create a foam layer that rises to the top of the foam tank. The fine solids will be adsorbed onto the foam, which can overflow the tank or be skimmed from the top.

Foam separation can be operated as batch or continuous operations.Batch processes will place the liquid mixture into a processing tank and produce foam until the majority of the product is removed.Product analysis can determine when the processing is complete, and the equipment can be re-filled and the process repeated.

Continuous production systems add the mixture either into the bottom of the vessel or at a point on the side. Air or other gas and surfactant are added at the bottom and are mixed as the gas moves upward. The foam will be carried to the top of the tank or a collection point on the side above the liquid level. Further processing can remove the surfactant from the desired product stream.

About Mechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Related Articles

Discussion Comments
About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.