12 Jun Types of water: chemical characteristics and applications in vehicle washing
Water is the fundamental resource in any vehicle cleaning and maintenance process. Its chemical composition directly impacts the effectiveness of the products used and the maintenance of the facilities. Below, we analyse the different types of water from a chemical perspective and their relevance to the car wash industry:
- Mains water
Mains water is supplied by municipal authorities and contains dissolved ions from the supply source. Its most common components include:
- Carbonates (CaCO3, MgCO3) and bicarbonates that determine its hardness.
- Chlorides and sulphates (Cl-, SO42-) that affect conductivity and corrosiveness.
- Trace metals such as iron (Fe) and manganese (Mn).
- Residual chlorine used for disinfection, but can react with some chemicals.
Its quality depends on the region and its origin, and can vary from water with very low conductivity to very saline water.
- Well water
Extracted from underground sources, its composition depends on the type of soil and the depth of the well. Compared to mains water, it has:
- Typically, a higher concentration of minerals such as calcium, magnesium, and iron.
- Possible contamination by nitrates and organic matter due to agricultural and industrial infiltration.
- Lack of chlorine, which makes it more susceptible to microbial growth.
Well water should be filtered and treated before use in washing processes.
- Dechlorinated water
This is tap water that undergoes a chlorine removal process using:
- Activated carbon, which adsorbs chlorine and its derivatives.
- Chemical reactions with sodium thiosulfate or sodium bisulfited.
Dichlorination is essential in systems that require subsequent softening, as chlorine damages the resins of ion exchangers and the membranes of osmosis plants.
- Decalcified water
It is obtained by removing calcium (Ca2+) and magnesium (Mg2+) ions through an ion exchange process using sodium (Na+) resins. Its benefits include:
- Prevention of limescale buildup in circuits and equipment.
- Increased detergent effectiveness by reducing interference from bivalent ions.
However, it does not remove other dissolved contaminants.
- Osmotized water
Subjected to a reverse osmosis process, a semipermeable membrane retains some of the dissolved ions. Features:
- Low electrical conductivity.
- Eliminates salts and heavy metals.
- Greater compatibility with chemicals, preventing unwanted reactions.
This is the recommended water for final rinsing and waxing, preventing stains and residue on the bodywork.
- Recycled water
The water used in washing can be recycled through filtration and physical-chemical treatment processes, including:
- Coagulation and flocculation to remove solid particles.
- Filtration and disinfection with biocides to prevent bacterial growth.
Although it reduces costs and drinking water consumption, its quality must be monitored to avoid blockages and contamination during the washing process.
From cleaning to rinsing: how to choose the right water
Each type of water has a specific application in the washing process:
- Pre-washing and rinsing: Recycled, well or mains water can be used.
- Rinsing: Ideally osmosed water or, failing that, decalcified water.
- Waxing: Osmosis water is required to avoid residues and stains.
Knowledge of the chemical characteristics of water is essential to optimise the vehicle wash process. Selecting the right type of water not only improves the efficiency of the chemicals, but also protects the equipment and reduces the environmental impact. Ibercompound experts can advise you on the best solution for every need, offering advanced water treatment technologies and guaranteeing maximum quality and sustainability in every cleaning process.
