All cleaning process should begin with dry soil removal and vacuuming

Dry carpet cleaning systems are more accurately known as “very low moisture” (VLM) systems, relying on dry compounds complemented by application cleaning solutions, and are growing significantly in market share due in part to their very rapid drying time,^[4] a significant factor for 24-hour commercial installations. Dry-cleaning and “very low moisture” systems are also often faster and less labor-intensive than wet-extraction systems.

Pre-treatments, pre-conditioners, or “traffic-lane cleaners

Detergents or emulsifiers that break the binding of soils to carpet fibers over a    short period of time, are commonly sprayed onto carpet prior to the primary use of the dry-cleaning system. One chemical dissolves the greasy films that bind soils and prevent effective soil removal by vacuuming. The solution may add a solvent like d-limonene, petroleum byproducts, glycol ethers, or butyl agents. The amount of time the pretreatment “dwells” in the carpet should be less than 15 minutes, due to the thorough carpet brushing common to these “very low moisture” systems, which provides added agitation to ensure the pretreatment works fully through the carpet.^[5]

Dry compound

An absorbent, 98% biodegradable cleaning compound may be spread evenly over carpet and brushed or scrubbed in. For small areas, a household hand brush can work such a compound into carpet pile; dirt and grime is attracted to the compound, which is then vacuumed off, leaving carpet immediately clean and dry. For commercial applications, a specially designed cylindrical counter-rotating brushing system is used, without a vacuum cleaner. Machine scrubbing is more typical, in that hand scrubbing generally cleans only the top third of carpet.^[6]

Encapsulation

In the 1990s, new polymers began literally encapsulating (crystallizing) soil particles into dry residues on contact, in a process now regarded by the industry as a growing, up-and-coming technology; working like “tiny sponges”, the deep-cleaning compound crystals dissolve and absorb dirt prior to its removal from the carpet.  Cleaning solutions are applied by rotary machine, “CRB” counter rotating brush, brush applicator, or compression sprayer. Dry residue is vacuumable immediately, either separately or from a built-in unit of the cleaning system machine.

According to ICS Cleaning Specialist, evidence suggests encapsulation improves carpet appearance, compared to other systems; and it is favorable in terms of high-traffic needs, operator training, equipment expense, and lack of wet residue. Encapsulation carpet cleaning also keeps carpets cleaner for longer periods of time compared to other methods.  Encapsulation also avoids the drying time of carpet shampoos, making the carpet immediately available for use.

The use of encapsulation to create a crystalline residue that can be immediately vacuumed (as opposed to the dry powder residue of wet-cleaning systems, which generally requires an additional day before vacuuming) is a newer technology that has recently become an accepted method for commercial and residential carpet deep cleaning.

Bonnet

A bonnet cleaning solution is applied to the surface of the carpet as a mist. An absorbent pad or “bonnet” is placed under a 175 Rotary or Oscillating Pad (OP) floor machine where it agitates the mixture with rotating motion. This attracts and removed the soil.  The bonnet is then rinsed and reused or replaced as they become soiled.  To reduce pile distortion, the absorbent pad or bonnet should be kept well-lubricated with cleaning solution.  The bonnet method offers improved overall appearance, fast drying, and high production rates.

Solvent extraction

A d-limonene based cleaner is pre-sprayed upon the carpet to be cleaned. The product is given a dwell time of 5–10 minutes. The carpet is then extracted using an acid rinse solution through a hot water extraction machine. Triple dry strokes are then performed to ensure a low dry time. While this process is not strictly dry cleaning and involves a 1-4-hour dry time, it cleans deep into the fibers.

Encapsulation Detergents

Encapsulation is when fibers are encased into crystal or film, which yields detergency to soil within a liquid solution and afterwards in a solid state. The chemical doing the encapsulation is called an encapsulant. Encapsulants are not always dependent upon polarity.

The difference between surfactant and encapsulant detergents is that encapsulant detergents have wet and dry, (solid) detergency; surfactant detergents have only wet, (liquid) detergency. The difference between encapsulant and protectors is that protectors only have solid detergency. Encapsulation detergents may be used in several different methods of cleaning such as hot water extraction.

1. Non-enduring which are crystallizers that are designed to become solids and be vacuumed up.
2. Enduring Films leave a polymer and/or acid dye blocker layer behind to help with wet stains and re-soiling. Small amounts are removed over time through vacuuming.

SURFACTANTS

1. Surfactants emulsify oils and suspend insoluble soils in liquids. Oils and polar soils are then suspended and carried away.
2. Surfactants are the vehicles for upward flow of soil left in the carpet. This phenomenon is known as “wicking.”
3. Surfactant detergents gain power with increased alkalinity.
4. Surfactants work with respect to polarity. Anionic’s suspend insoluble substances; nonionics emulsify oils.

ENCAPSULANTS

1. Encapsulants have limited liquid detergency plus solid detergency and their residue allows protection afterwards.
2. Encapsulants hold back wicking
3. Films are indifferent to changes in pH; crystallizers make their formation at a specific pH.
4. Encapsulants work without respect to polarity.
5. Surfactants generally do not remove soil under four microns. (A micron is one millionth of a meter.)
6. Encapsulants work without respect to size.
7. Surfactants work much better under dilution.
8. Encapsulants do not work as well under dilution. They work best in high concentrations.