green chemistry
The chemical mixing industry will soon see improvements in the race toward sustainability.

As younger generations begin to enter the workforce, the focus on sustainability and “green” chemistry has increased at a rapid pace due to a climate crisis created, at least in part, by manufacturing pollution and waste.

Modern life relies on chemical processes and manufacturing, from pharmaceuticals to cleaning products and fuel to fertilizers. Historically speaking though, convenience came first, with any concern about the environment taking a backseat to profits.

The race toward products that made life better worked in some ways, but unless chemists and manufacturers increase their focus on green initiatives and sustainability, the convenience these products provide will not be worth the price being paid.

Approach to Sustainable Chemical Mixing

The approach to sustainability comes in two separate courses of action. The first is cleaner chemical reactions when mixing. The second is reduced energy needed from the equipment mixing the chemicals.

Green chemistry investigates solvents that are easier to dispose of, chemical mixes that create fewer byproducts and chemicals that avoid, or at least minimize, hazardous materials and the chemical waste that results. These specific needs require a whole new strategy, which requires visualizing the process from start to finish to determine what is needed and what will result so that cleaner processes and materials might be substituted wherever possible.

Approaching chemical mixing with green sensibilities makes even more sense when considering which products often result from chemical mixing processes. An estimated 8.3% of all deaths have been linked to chemical exposure, and another 5.7% to total disease worldwide. Consumers feel safer when using fragrances, moisturizers, over-the-counter and prescription medications, foods—both human-grade and pet formulas—and cosmetics that are created using safe, green chemistry principles and processes.

Concentration on cleaner chemicals and solvents helps to alleviate other issues that can arise from chemical mixing and processing. Air and soil pollutants from steam, acid rain, byproducts and waste are less likely to result when cleaner processes are used. Correct disposal of chemical waste has been subject to more stringent laws and regulations, meaning a cleaner future for younger generations.

With cleaner mixing and manufacturing addressed, the next course of action concerns the amount of energy needed for production. Currently, the chemical plant industry consumes massive amounts of energy, with the highest final energy consumption of any industry. Massive amounts of water are also necessary, which has contributed to water scarcity in many areas of the world, particularly those that may have already experienced scarcity before chemical plants added to the situation.

Evolving regulations have put pressure on chemical plants to update, upgrade and innovate to meet key performance metrics for reduced energy consumption. Improvements in equipment help to reduce the power needed, which results in lower energy consumption. These innovations are available for a vast array of machinery to provide solutions for common problems. For instance, viscous mixtures may have required increased energy, water and time to clean and prepare for new blends in the past. New improvements include blades to scrape the sides of the vessel during the blending process for reduced remnants after emptying. As another example, rotor-stator mills have been the conventional equipment in dry milling for particle size reduction and deagglomeration; however, newer, high-shear wet mills present a safer, more efficient alternative to dry milling.

First, it eliminates dust formation, cutting the need for solutions like dust removal systems, inert gas purging and dedicated containment. Additionally, high-shear homogenizers create 55 times more shear energy than conventional rotor-stator mills. The use of a high-shear homogenizer will often result in finer particle size in just a single pass.

Another option is an automated system that can accelerate product transfer to reduce the time between emptying the vessel and preparing it for cleaning, so the product has less time to dry or stick to the sides of the container. Any area where automation is possible gives more opportunity for decreased energy consumption. Automation often means greater efficiency and accuracy, which means less repetition and waste.

For example, a United States-based pharmaceutical manufacturer producing injectable radiographic contrast media was relying on the manual addition of a powder solid into sterile water for injection. The solids had to be added slowly to limit dust contamination, ensure efficient mixing and avoid buildup of the powder on the bottom of the mixing tank. Through the introduction of a new system combining vacuum transfer technology and a high-speed inline powder disperser, the manufacturer was able to eliminate this step, thereby streamlining the process, maximizing efficiency and minimizing cleanup and product loss.

Alternative Energy Sources

Where possible, renewable energy sources will be used to consume less power and optimize the energy sources available. Solar, wind, geothermal and water power can control lights, computers and electronic systems. While these are generally supplemental energy sources, they can be used throughout the plant for significant reduction in consumption.

While many large plants may not yet generate enough alternative energy from solar or wind sources to power mixing and manufacturing equipment, many have continued to push toward systems that fully rely on renewable energy. Continued efforts from all chemical manufacturers will result in zero reliance on nonrenewable power sources.

In the meantime, any equipment and systems within the plant that can use environmentally friendly products—such as light-emitting diode (LED) lights that consume up to 80% less energy per year than traditional incandescent bulbs—will put users on the right track toward sustainability. Heating and air conditioning units can also be replaced with more efficient models to lower gas and electricity usage.

The Financial Benefits

In addition to leaving behind a better world for future generations, there are also several financial benefits to considering sustainable processing systems for chemical mixing and manufacturing. A good place to start lowering costs is by avoiding fines and audits as government entities continue to increase regulations and laws. This is by no means the least that should be done, but is a great first step toward truly green chemical mixing and blending. Lower energy and water consumption and automated processes that lead to higher efficiency will also help reduce spending.

Younger generations are more socially conscious and prefer to find employers that harbor similar beliefs. A strong sustainability program within a plant would be attractive to new recruits, as well as investors who are excited to see profits and productivity rise as a result.

Mixing Industries on the Cutting Edge

The latest chemical mixing equipment has been developed with green sensibilities at the forefront, with an eye toward reserving byproducts for future use, efficient performance for less energy consumption and new designs with water conservation solutions.

Attention to green practices has led several industries to innovate, or in one case, look back to ancient methods. Mechanochemistry has been used in some areas to speed up the reaction process, using ball mills for reduced energy use and  a reduction in solvents needed. A pyrolysis plant has discovered how to process various plastic types to recycle more plastic than ever.

Some concrete mixers have rediscovered the ancient method used for centuries-old aqueducts, monuments and coliseums could be the answer to creating more durable and environmentally friendly concrete. “Hot mixing” with quicklime has proven to heal cracks within the concrete, which means our buildings and bridges will soon last much longer.