To answer specific applications and meet industry regulations, many major lubricant manufacturers are producing biodegradable lubricants.
A biodegradable lubricant, sometimes called a bio-lubricant, is specifically produced to minimise environmental harm by degrading rapidly and naturally through the activity of living organisms, instead of remaining in the environment for longer – like standard mineral oils.
Composed from plant-based oils such as sunflower and rapeseed oils, or specially designed synthetic esters, they provide the same function as a mineral oil. They reduce friction during mechanical processes while cooling and cleaning equipment and defending it against corrosion. However, unlike conventional mineral oils, biodegradable lubricants are especially suited to environmentally sensitive applications like construction, marine and forestry, where lubricant leaks have a substantial negative impact when they occur.
While biodegradable oils, greases and fluids offer tangible benefits, they also have certain shortcomings. Here, we explore the pros and cons of these environmentally sound solutions in detail.
Advantages of biodegradable lubricants
The latest biodegradable lubricants are designed to provide superior environmental protection. Their formulation allows them to naturally degrade into harmless substances. This effectively minimises damage to air, soil and water.
Biodegradable fluids support regulatory compliance, helping firms navigate and adhere to environmental regulations and meet their established environmental, social and governance (ESG) aims. Using more sustainable solutions like bio-lubricants can also enhance an organisation’s green credentials and reputation, helping them win contracts in more environmentally sensitive locations.
Compared to mineral oils, bio-fluids promote reduced system deposits thanks to their oxidation stability, improving lubricant lifespan in the system. Generally, they also offer higher flash points, making them less likely to ignite and safer for workers to handle.
Many fluids made with plant-based materials offer high lubricity and a high and stable viscosity index (VI). This allows them to operate at a range of temperatures while effectively reducing wear and tear on equipment.
Biodegradable lubricants also offer strong domestic agricultural support. Effectively minimising environmental damage, they protect farming resources. Less toxic to animals and plants, they pose a lower threat if spills and leaks occur and protect soil, water, crops and livestock against contamination.
Disadvantages of biodegradable lubrications
While bio-based fluids have their benefits, they come at a cost. Typically, these lubrication solutions are around 30 to 40 per cent more expensive than standard mineral-based options.
Biodegradable products also have certain performance limitations compared to mineral oil alternatives. Many bio-lubricants provide poor thermal stability, causing degradation – and at high temperatures, this leads to debris build-up.
Vegetable-based biodegradable lubricants usually have a shorter service life and shelf life compared to mineral-oil-based solutions. Formulations also feature less advanced additives, as many of the inclusions needed for anti-oxidation, anti-wear and corrosion protection are predominantly petroleum-based, lowering the environmental benefit of a lubricant.
In terms of low-temperature performance, biodegradable lubricants can struggle. For instance, at sub-zero temperatures, they experience poor pumpability and crystalise. This limits deployment in cold environments.
Compared to their mineral oil-based counterparts, bio-lubricants have lower oxidative stability. This means that they are often more susceptible to thermal and oxidative that can cause the lubricants to become more acidic and more viscous.
Hydrolysis is another significant disadvantage of bio-based fluids, especially synthetic-based and vegetable-based lubricants. This is because it makes the lubricant begin to breakdown and, as a result, harmful byproducts can start to form. The process of hydrolysis degrades the fluids sought-after performance properties, leading to corrosion and damage to mechanical components. In extreme cases, it can result in a total system failure.
System compatibility can be a major issue for bio-based lubricant users. While more sustainable, these fluids are not always fully compatible with seals, hydraulic systems and other components in use. Additionally, biodegradable lubricants are not usually compatible with conventional mineral oils. As a result, before adoption, operators must conduct a comprehensive flush and purge of their system. This process can be both costly and time consuming.
Do you require biodegradable lubricants for your operation?
There is no doubt that biodegradable lubricants can aid in maintaining the environment and support reduced demand on mineral oil use going forwards. However, it is vital that the lubricants selected are always a match for their specific application. To access high-quality biodegradable lubricants, reach out to our Oil Store team for details.
