What are the Differences Between Solvent & Aqueous Cleaners?

What are the Differences Between Solvent & Aqueous Cleaners?

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When it comes to parts washing, there are two standard cleaning methods used: aqueous and solvent cleaning. But which one is the best choice? Industrial and manufacturing businesses commonly rely on assistance from detergents or solvents to remove oil and grease, dissolve paint and resins, and clean parts, tools, and equipment. Choosing a cleaning solution for your components determines performance and cleanliness, and learning about your options for sustainable, effective cleaning solutions affects your bottom line. This blog post will look at the differences between aqueous and solvent cleaning and consider how they affect the environment. We’ll also explore how aqueous cleaners work in parts washing to help you decide which option suits your needs. Learn more about aqueous and solvent cleaning in parts washing from Better Engineering Mfg., your trusted parts washing company.

Why is Parts Washing Vital to Your Business?

Parts washing is crucial in various industries, including automotive, aerospace, manufacturing, and electronics. It is a critical step in ensuring the quality, functionality, and longevity of parts and components.

During manufacturing, parts can accumulate dirt, oil, grease, and other contaminants that can negatively impact their performance and reliability. Parts washing is essential to remove these contaminants and prepare the parts for further processing, assembly, or packaging.

Failure to properly clean parts can result in numerous issues, such as reduced efficiency, decreased product lifespan, and equipment failure. Contaminants left on parts can lead to corrosion, friction, or even electrical shorts, which can significantly affect the overall functionality and safety of the final product.

Parts washing also plays a vital role in maintaining the overall cleanliness and safety of the manufacturing environment. Contaminated parts can introduce pollutants into the production area, leading to health hazards for workers and potential damage to equipment. By ensuring thorough cleaning, parts washing contributes to a safer working environment and improves overall operational efficiency.

What is aqueous cleaning?

Aqueous cleaners are water-based cleaning solutions free from volatile organic compounds (VOCs). This method uses detergents, surfactants, agitation, and pressurized spray to decontaminate your industrial parts. These cleaners use surfactants, alkaline or acidic agents, and water to break down and remove contaminants. Overall, aqueous cleaning is more sustainable, has a higher safety margin, and stable, non-VOC composition.  

During the cleaning process, the aqueous cleaning solution is heated and circulated around the parts to be cleaned using pumps and nozzles. This circulation and heat help to activate the surfactants, which then break down the grease, oil, or other contaminants on the parts. The cleaning solution is then rinsed off the parts, leaving them clean and free from residual contaminants.

Aqueous cleaners are highly effective at removing various contaminants, including oils, greases, dirt, and grime, making them ideal for use in multiple industries. In addition, these cleaners are safe for use on most types of materials, including metals, plastics, and composites.

Overall, aqueous cleaners offer an environmentally friendly, cost-effective, and efficient way to clean parts and components. With no harmful VOCs or toxic waste to dispose of, they are preferred by many industries looking for a safer, more sustainable cleaning solution.

What is solvent cleaning?

Whereas aqueous cleaners use water as the primary solution for cleaning, solvents are pure chemical cleaners that you can combine to maximize performance. Solvent cleaners work by dissolving soil and grease on parts; as most solvents contain alcohol, acetone, ethanol, or butyl acetate, they evaporate, leaving behind a clean component. 

Solvent cleaning is a widely-used method in parts washing but has a significant environmental impact. Solvents are typically made from petrochemicals, which are non-renewable and contribute to greenhouse gas emissions. Moreover, solvents contain volatile organic compounds (VOCs) that are known to be hazardous to human health and the environment.

During solvent cleaning, VOCs evaporate into the air and can lead to ground-level ozone formation and air pollution. Solvent waste also threatens soil and water quality when not disposed of properly. 

Environmental laws, such as the Clean Air Act and Clean Water Act, have regulated the use of solvent cleaning. However, stricter regulations are continually being implemented, pushing companies to move towards more eco-friendly alternatives.

Choosing aqueous cleaning over solvent cleaning eliminates harmful chemicals and VOCs and offers a more cost-effective and efficient solution. As technology advances, aqueous cleaning becomes a more viable option in industries that once solely relied on solvent cleaning. By switching to aqueous cleaners, companies can minimize their environmental impact and improve their bottom line.

What are the Major Differences Between Aqueous and Solvent Cleaning?

When it comes to cleaning parts, both aqueous and solvent cleaners have advantages and disadvantages. Solvent cleaning is known for its effectiveness in removing tough oil and grease stains from metal parts. However, this cleaning method also poses significant environmental risks due to the release of hazardous chemicals and the generation of hazardous waste.

On the other hand, aqueous cleaners are less hazardous and better for the environment but may not be as effective in cleaning certain types of parts or removing stubborn stains. However, advancements in aqueous cleaning technology have made them more effective in recent years, with many aqueous cleaners able to clean parts as effectively as solvents.

Ultimately, the choice between aqueous and solvent cleaning depends on various factors, including the type of parts being cleaned, the type of contaminants being removed, and the desired level of cleaning. While solvent cleaning may be more effective for certain types of parts and contaminants, aqueous cleaning is becoming increasingly popular due to its environmental friendliness and effectiveness in many applications. Companies must weigh each cleaning method’s pros and cons before deciding which one to use for their parts washing needs.

Both aqueous and solvent cleaners achieve the same cleanliness level, but there are a few key differences between the two:  

  1. Evaporation vs. Rinsing and Drying: Water-based cleaners don’t evaporate at the same rate as solvent cleaners and must be rinsed and sometimes dried to remove any leftover residue. As stated above, solvent cleaners usually contain alcohols such as ethanol or isopropanol, which don’t require rinsing. Additionally, the evaporation process takes less time than rinsing and drying. 
  2. Environmental and Health Impact: Solvents often prepare metals for different finishing processes like welding or painting and contain VOCs (volatile organic compounds). VOCs have significant short- and long-term detrimental effects on the health of humans and the environment; their gaseous nature contributes to the depletion of the ozone layer. Since they have water-based chemistry, aqueous cleaners, while potentially dangerous when dealing with solutions on the far ends of the pH scale are relatively nontoxic.  
  3. Reactive Additives: Additives to aqueous cleaners, such as chelating agents, saponifiers, and builders, are incompatible with all materials. They can react aggressively and cause metals or plastics to break down and not function as intended.

Why choose aqueous cleaners?

Although solvent cleaners are efficient, when it comes to impacts on health and the environment, there’s no question about which option is safer. Solvent cleaners cause illnesses ranging from skin and lung irritation to affecting the central nervous system, among other complications, including loss of life. 
According to Environmental Protection Agency (EPA) studies, the industrial sector accounts for 22% of greenhouse gases released into the air. Many companies seek safer, more eco-friendly solutions such as water-based solutions. Aqueous cleaners offer a more sustainable solution using water-soluble and biodegradable detergents, making them safer for users and the environment.

Which chemistry best fits your applications?

Both aqueous and solvent cleaners have the potential to be effective. Still, cleaning depends on the contaminant, substrate, and regulatory requirements. It is essential to note that many regulatory bodies force manufacturers to evaluate solvents for environmental and health concerns carefully, causing water-based cleaners to be more common as they are safer.  

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