What Is Distillation in Drycleaning?

Distillation is the process drycleaning machines use to remove contaminants from solvent. During cleaning, solvent absorbs dyes, fatty acids, detergents, and other soils. If those contaminants are not removed, solvent quality declines and cleaning results become inconsistent.

Distillation restores solvent clarity by separating clean solvent from dissolved contaminants.

Why Is Distillation Important?

Distillation is not just a maintenance task. It is a core operational system.

When distillation is working properly:

• Solvent stays clear

• Cleaning performance remains consistent

• Dye and odor risks are reduced

• Waste is controlled

• Equipment operates more reliably

When distillation is ignored or underperforming, problems compound quietly and become expensive.

How Does Distillation Work?

Distillation happens in three steps.

Vaporization

The solvent is heated until it reaches its boiling point. Because solvent boils at a lower temperature than contaminants, only the solvent turns into vapor. The contaminants remain behind in the still.

Condensation

The solvent vapor passes through a cooling coil. As it cools, it turns back into liquid solvent.

Separation

The liquid solvent flows into a separator, where any water or moisture is removed before the solvent returns to the machine.

Only clean, dry solvent is reintroduced into the system.

What Types of Stills Are Used in Drycleaning?

Atmospheric Stills

Used in perchloroethylene systems. These operate at normal atmospheric pressure. Proper steam pressure and condenser water temperature are critical for efficiency.

Vacuum Stills

Used in non-perc systems. These operate under partial vacuum, lowering the boiling point of the solvent and reducing the risk of solvent damage.

What Are Common Distillation Problems?

Reduced solvent flow

• Low steam pressure

• Dirty condenser coil

• Incorrect water temperature

• Excessive still residue

Cloudy or milky solvent

• Water leaks in steam or condenser coils

• Faulty water separator

• Excess moisture in the solvent

Dirty distillate

• Excessive steam pressure

• Severely contaminated solvent

• Too much detergent

• Solvent boil-over

Poor vacuum performance

• Leaking vacuum pump

• Damaged vacuum lines

• Faulty check valves

What Is the Bottom Line?

Clean solvent does not happen by accident.

Distillation is the system that protects solvent quality, cleaning consistency, and operational stability. When it works, problems stay manageable. When it fails, risk becomes invisible and costly.