Colloidal systems are those systems in which one substance is in the other in the form of small particles. Often they are also called colloid-dispersed, since the formation of these systems is a chemical process of condensation and dissolution of one substance in another, in which the particles of the dissolved substance are in constant (Brownian) motion. A vivid example of colloidal dispersion systems are emulsions, suspensions, foams and various bulk materials.
Colloidal systems for humans play a large role. In fact, the human body is one common colloidal dispersion system. Because in the body almost all substances are dissolved in one another and are in constant motion. The main biological colloidal systems of the body are blood and cell. The cell consists of a nucleus, ribosome, lysosome, Golgi complex, EPR - a substance that combines the cell into a whole, hyaloplasmas and membranes.
The nucleus is a colloidal medium that is responsible for protein biosynthesis and DNA stability. In the membrane, colloidal substances are responsible for the elasticity of the membrane and carry out a protective function. Hyaloplasma is a complex compound of colloids, in the cell they participate in biochemical processes, since they can independently transfer from one substance to another.
Blood is also an example of body tissue, where the basis is a colloidal dispersion system. Blood elements, which include red blood cells, platelets and white blood cells, are colloids, and
blood plasma is a dispersion medium. In plasma, all
organic substances can be called colloidal. The basis of the plasma is water, it creates a dispersed medium in which the organic components of the plasma are located: large protein molecules, amino acid molecules, mono- and polysaccharides, and many others.
Colloidal systems play an important role not only in the life of the human body. They have great applied value. Based on the study of colloidal-dispersed processes, new materials were created, many chemical processes were invented, which are actively used in production, as well as for water treatment (including wastewater).
The use of a biological water treatment system is becoming increasingly important, as the supply of fresh and potable water is reduced. Water purification with chemicals leads to even greater environmental pollution.
Biological water treatment involves the use of special microorganisms that process the organic components of
wastewater. Colonies of special bacteria form peculiar colloidal systems in the form of thin suspensions. During the life of such a colony, the bacteria that enter it purify the water from pollution.
Biological water purification can be of two types: natural purification, in which microorganisms receive oxygen from the environment, and artificial, in which microorganisms function in closed systems, and oxygen is supplied to them by mechanical aeration.