by Cynthia Challener, CoatingsTech Contributor

Sustainability in the coatings industry continues to evolve.  Manufacturers of resins, additives, pigments, and final paint  formulations have expanded their focus from the development of greener products to include the design of greener processes that consume fewer resources and produce less waste and emissions.  The most successful companies have established formal programs to drive awareness, encourage innovation, and enable the ongoing implementation and improvement of sustainable operations. The results speak for themselves. Green manufacturing does not just benefit the environment—it has a measurable, positive impact on competitiveness and profitability.

Why Green Chemistry?

The concept of green chemistry was initially introduced by Paul Anastas and John Warner in 1998 when they outlined the 12 Principles of Green Chemistry.1 These principles focus on efficiency and hazard reduction as a means for developing sustainable processes. For PPG, they guide research and manufacturing efforts, because they prescribe the right things to do and they make good economic sense, according to Bill Schillinger, PPG global director of manufacturing technology. “The 12 Principles of Green Chemistry provide PPG employees with a developmental roadmap for sustainable efforts that helps us to improve efficiency and drive down our impact on the environment,” he explains.

Sustainability serves as a lens for how companies do business, according to Cathy Combs, director of sustainability for Eastman Chemical Company. “As the world changes, the needs for sustainable operations, products, and practices change. As our company continues to grow and change, the need for creating innovative, sustainable solutions while maintaining sustainable operations also increases. We monitor and develop solutions that respond to global macro trends, including health and wellness, the emerging middle class, natural resource efficiency, and feeding the world’s growing population,” she says. Global megatrends such as population growth, climate change, urbanization, etc., are placing increasing pressure on available resources and drive the need for more sustainable production and consumption, adds Lynette Chung, head of corporate sustainability strategy & advocacy with Clariant International Ltd. There is, in fact, a clear correlation between these megatrends and the need for performance materials that can improve lives, while offsetting significant environmental impacts like energy and resource consumption, according to Rebecca Lucore, head of sustainability in North and South America for Covestro LLC.

Indeed, the creation of more value from fewer resources is necessary to achieve business success for both coatings manufacturers and their customers, according to Ruud Morssinkhof, program manager of operational eco-efficiency with AkzoNobel. “From a manufacturing perspective, that means using raw materials that are more energy and material efficient for our operations, ensuring an improved energy efficiency and fuel mix for our energy-intensive operations, and making improvements in formulation (e.g., by using biobased raw materials) to reduce the product footprint,” he observes.

Covestro also sees great opportunity for meeting environmental and social sustainability challenges by frequently rethinking the way materials are produced and improving manufacturing processes. “It’s often a long, arduous cycle,” Lucore says, “but with every innovation that makes it to full production capacity, we can quantify the overall, improved life cycle of end products and make our facilities cleaner, safer, and more efficient.”

PPG sees green chemistry and sustainability as value creators for both its shareholders and customers. “Considerations such as cost of compliance, environmental control, and potential future liability all factor into the creation of a competitive product for today’s marketplace. The cost to manufacture and deliver a well-designed product is generally less when all contributory factors are considered. In addition, greener products tend to have an inherent value that many customers actively seek. Having such coatings and materials in our product portfolio offers us access to customers we might not reach otherwise,” Schillinger notes.

Increasing focus from customers to have their supply chain committed to a reduced environmental footprint is also a big driver for Axalta Coating Systems. “This interest reflects their own programs to reduce their impact on the environment just as we look for ways to have our suppliers behave responsibly,” says Eric C. Tenuto, Axalta’s director of environment, health, safety and security. The responsible use of resources and the environment is increasingly becoming an important consideration as the environmental sustainability of products has become a central decision criterion for consumers, which impacts coatings manufacturers, agrees Chung. She adds that sustainability saves costs for the company and allows for business opportunities where Clariant can provide its customers with solutions to their particular needs and sustainability objectives. Tenuto agrees that it is also good business sense to be as environmentally responsible as is feasible—it offers a competitive advantage due to the lower costs that can result from adopting some of the latest environmentally focused technologies. Regulations also play a role, of course.

Reducing Energy and Water Consumption

For many companies in the coatings industry, a top goal for process improvement efforts and the implementation of greener manufacturing processes is to reduce energy consumption. “CO2 is a global issue. Reducing fossil energy usage promotes a net savings for global and local environments,” says Bill Klutz, environmental manager for Evonik. Energy consumption goes hand-in-hand with CO2 emissions, so reducing the amount of energy is a major goal, agrees Heubach’s business unit leader, Robert Poemer. He adds that for pigment manufacture, there is a lot of washing and wet milling, so the use of a closed cycle is essential for reducing water consumption. “It’s important to aim to reduce impacts on multiple levels (energy use, resources and emissions, cost effectiveness, and increased productivity), but it is equally important that any reduction technologies have the potential for scale in other regions and possible expansion to other applications so that their benefits are appreciably widespread,” adds Lucore.

Evonik has achieved energy conservation through a waste-to-energy program designed and managed by individual production units. By incorporating waste-to-energy, not only is the required quantity of natural gas reduced significantly, the net production of usable steam for production is achieved, according to Klutz. The company also used advanced leak detection technology to detect natural gas leaks and promote energy efficiency. Similarly, PPG has invested in reducing the amount of natural gas consumed to operate on-site vapor incinerators. The technology was first installed at the company’s Springdale, PA, site at a cost of nearly $1.5 million and is being implemented across other global PPG sites as new facilities are constructed, according to Schillinger.

Heubach, meanwhile, has installed new oven technology specifically designed to significantly reduce the amount of energy needed per ton of pigment. Development of the oven technology required significant effort on the part of the R&D department. “It took several trials at small scale to achieve the required uniformity of heat transfer. This experience was then used to build a new commercial-scale oven,” explains Poemer. The company is planning to install a second oven that will be further optimized based on the experience gained with the first one. Clariant points to CHF 6 million of annual savings due to improvements in energy efficiency achieved through its in-house eWatch program, including investments in the optimization of production facilities and the training of its employees.

Eastman Chemical Company uses cogeneration, or Combined Heat and Power (CHP), to generate its own steam and electricity, converting more than 70% of its fossil fuel energy into power and steam for manufacturing processes. The company’s Kingsport site received a CHP Award in 2014 from EPA for the efficiency of its cogeneration deployment. Eastman is also converting boilers from coal to natural gas and is anticipating a 60% reduction in greenhouse gas emissions once the project is completed, according to Combs.

Large strategic projects at AkzoNobel also include major energy reduction initiatives, such as implementation of the latest generation membrane electrolysis technology for chlorine production in Frankfurt, which was implemented in 2014. This €140-million project achieved a capacity increase of 50% while reducing the plant’s overall ecological footprint by 20%. Another key goal for the company is to increase the amount of renewable energy in its operations from 5% in 2009 to 45% by 2020, and it is well on its way, already reaching 38%. Covestro has also reduced electricity consumption and emissions during the production of chlorine through the development of oxygen-depolarized cathode (ODC) technology, which uses up to 30% less electricity than traditional membrane processes, according to Lucore.

Covestro switched from a traditional liquid-based process to gas-phase technology for the production of toluene diisocyanate (TDI), which uses much less energy. In the gas-phase process, toluene diamine (TDA) and phosgene react in a gaseous state rather than as liquids, leading to an 80% solvent savings and 60% energy savings when compared with the traditional process, according to Lucore. In addition, a typical, large-scale plant (with a production capacity of 250,000 metric tons of TDI) operating with gas-phase technology emits 60,000 metric tons less CO2 annually than a similar-sized plant operating with a liquid-based process. Further benefits include a higher yield, a reduction in the required quantity of phosgene by 40%, and 20% lower capital costs.

Increasing Resource Efficiency

Increasing overall resource efficiency is another key goal of many manufacturers in the paint and coatings industry. “At PPG, we want to convert absolutely all of the materials used in our processes into saleable products,” states Schillinger. In addition to improved energy intensity and water conservation, Axalta’s goals include reductions in hazardous waste generation and disposal and greenhouse gases and VOCs, plus maintaining the company’s multi-site RC14001 certification as part of the ACC’s Responsible Care program. “We have chosen these goals because there is a direct impact on operations and across the supply chain.  The integrated and consistent approach that’s reflected in the RC14001 certification demonstrates a leadership commitment to operate in a manner across all stages of the supply chain and manufacturing processes,” says Tenuto.

Covestro focuses on finding new ways to reduce resource consumption or develop closed-loop processes, which often come with the added benefits of energy and emissions reductions or water protection. For instance, the company is currently testing a recently developed, innovative process for recycling saline process wastewater in polycarbonate and polyurethane production. The new technology reduces the salt levels in waterways and conserves potable water resources. A pilot plant for the process was recently opened at the Krefeld-Uerdingen plant. Pretreated salt water is usually released into waterways, specifically the Rhine River that runs directly along the site. “This new chlorine recycling process helps save up to 30,000 metric tons of salt and 400,000 metric tons of fully desalinated water in chlor-alkali electrolysis every year. That corresponds to emissions reduction totaling 6,200 metric tons of CO2 equivalents annually,” notes Lucore.

At its facilities in India, Heubach has developed a new approach to managing the waste generated during the production of phthalocyanine pigments. The conventional method for treating CPC Green ML pigment containing aluminum chloride and metallic impurities is to neutralize with lime and isolate the wet solid sludge, 13-14 tons of which is obtained for every ton of pigment. “Our process, which to the best of our knowledge is unique to Heubach, involves the recovery of pharmaceutical grade aluminum hydroxide gel, which is sold as a valuable product,” Poemer states.

Other Approaches

There are numerous other innovative approaches to developing and implementing green manufacturing processes in the coatings industry. PPG, for instance, has research teams that are constantly looking for ways to replace solvent-based materials and processes with those based on water and seeks ways to incorporate higher levels of renewable materials, such as replacing metal catalysts with novel environmentally friendly catalysts and using biorenewable raw materials such as natural oils and other monomers. “Not only does using these materials reduce our environmental impact, it also gives our products unique performance,” Schillinger comments. PPG has also identified its top 100 suppliers by spend, and surveyed and graded them on their sustainability efforts with the goal of driving its sustainability vision back up the value chain.

Eastman is also focused on expanding green manufacturing beyond its own production facilities through collaboration along the value chain. “We want to develop solutions that enable our customers and downstream partners to improve the sustainability of their products and processes,” remarks Combs. “We have a team dedicated to completing life-cycle assessments of Eastman’s products to help us understand the impact of our products and processes as well as identify opportunities for further improvement and value chain engagement,” she adds.

Covestro, meanwhile, has demonstrated that it is possible to harvest waste CO2 emissions from sources like power plants to make raw materials such as polyols. In cooperation with Germany’s RWTH Aachen University, the company developed a process that uses waste CO2 as a useful raw material to replace approximately 20% of the petroleum consumed in the polyol production process, according to Lucore. This innovative concept is part of Covestro’s Dream Production project. Scaled production will start in the first half of 2016, and the company is already setting its sights on a second process that utilizes CO2.  In March 2016, the company announced that the German Ministry of Research is funding an additional project that will enable CO2 to be used in the sustainable manufacture of elastomers on an industrial scale.

Green Biologics has focused on fermentation processes as a means for achieving the greener production of solvents that are important to the paint and coatings industry. With enzymes as catalysts rather than transition metals, the reactions are much more specific and provide the desired products in much higher selectivities, according to Lee Colyer Speight, Green Biologics’ manager for Technology & Downstream Products. He also notes that fermentation does not require the use of carcinogenic starting materials, and there are strong driving forces to consume the starting materials and intermediates leading to products with higher intrinsic purities than those obtained using traditional chemical synthesis methods. “Higher purity means less waste and greener processes,” Speight asserts.

In addition, Green Biologics employs a proprietary Advanced Fermentation Process™ to manufacture 100% biobased and renewable n-Butanol and acetone. “Our manufacturing challenges going forward include continued optimization of the fermentation process to maximize product yield efficiencies. Ultimately we look not only to be a direct supplier of renewable butanol and acetone to paint and coatings companies, but also to downstream monomer producers for the manufacture of biobased, renewable butyl acrylate, butyl acetate, and/or butyl glycol ethers,” concludes David Anderson, global vice president of marketing for Green Biologics.

Formalized Programs Help Overcome Challenges

Most companies that have been successful at implementing widespread green manufacturing processes use a formalized program to evaluate sustainability performance gaps and follow through with the development and adoption of effective solutions. PPG, for instance, has a mature process for measuring and managing its energy, water, and raw material utilization in order to minimize waste and reduce its carbon footprint. “While we are devoted to commercializing new green products, PPG sees the greatest value in creating green-by-design projects. Using sustainable materials that are uncoupled from fossil fuels reduces our environmental footprint, and making polymers in water-based solutions instead of solvents helps reduce harmful emissions both in manufacturing and on the consumer end. Additionally, creating and supporting manufacturing processes with shorter cycle times and that require less heat helps save energy and cost for both us and our customers,” observes Schillinger.

As a fairly new independent company, Axalta is in the early stages of developing its comprehensive objectives and environmentally related targets.  One major global initiative has been the commitment to the American Chemistry Council’s Responsible Care initiative. The company does, however, already practice environmentally responsible design in many of its facilities, and the company culture emphasizes having a high awareness of so-called green objectives, according to Tenuto. “One challenge is balancing the need to meet multiple targets and assessing the tradeoffs between investing in optional environmentally oriented projects versus others that offer a potentially higher financial return,” he notes. Evonik is also proactive in addressing sustainability issues. “Efforts begin with the design of processes considering environmental mass and energy balances. From there, we assess the feasibility of waste minimization and waste usage on-site prior to startup. Implementation is part of the design as well. The use of technologies to reduce or eliminate emissions is encouraged and has not been a barrier,” says Klutz.

Clariant has a number of official initiatives that focus on sustainability. First is the environmental reduction targets (30–40% of 2013 levels by 2025) of energy consumption; direct CO2 emissions; direct and indirect GHG emissions; water consumption; wastewater; and waste  that cover the key environmental impacts of its operations and are therefore good indicators for continuous improvement of the company’s environmental manufacturing performance, according to Chung. The Clariant Production System YEE (Yield, Energy, Environment) was established in 2013 as part of the Clariant Excellence efficiency improvement initiative. This program focuses on cost savings and benefits related to raw materials, energy, and the environment. As a result, CHF 39 million in savings were realized from 2013 to the end of 2015. The planned target is approximately CHF 60 million by 2017/2018. The company’s Portfolio Value Program (PVP), which began in 2012, evaluates Clariant’s product portfolio, considering 36 sustainability criteria and all aspects of the product life cycle. Through this systematic, detailed review process, product groups are identified that have good sustainability performance or outstanding sustainability advantages. In the latter case, Clariant distinguishes such products with its sustainability excellence label EcoTain. The system also helps identify product groups for which there is a need for change in their sustainability—whether through innovation, replacement, or phase-out. All future innovations at Clariant will be measured against these criteria. Finally, in order to comparatively assess development projects from both manufacturing and product property perspectives early in the innovation pipeline, Clariant has introduced the Corporate Sustainability Index for Research and Development projects (CSIR&D).

Eastman defines corporate sustainability goals to support the three pillars of sustainability—environmental, social, and economic. In addition, the environmental goals outlined in its annual sustainability report link closely with the sustainability of its manufacturing operations. For example, by 2020, the company has set goals to reduce energy intensity and GHG intensity by 20% against a 2008 baseline. “We are mindful that our manufacturing processes require large amounts of resources, including energy and water. Our overarching objective is to embed sustainability across the company and along the value chain, and we work hard to create a culture where sustainability is embedded into every aspect of our company, including manufacturing,” Combs notes.
Eastman’s sustainability council with executive team and senior management members that represent a cross section of the company is structured as one governing body with four subcouncil teams representing the four focus areas of the council: Trends-based Innovation, Design and Natural Resources, Environmental Stewardship, and Corporate Social Responsibility. The subcouncils are responsible for defining Eastman’s sustainability goals, tracking progress against goals, and working with the council to outline and execute the company’s sustainability strategy and address potential issues and challenges.

AkzoNobel, meanwhile, has adopted the Planet Possible agenda, which reflects its commitment to doing more with less. Its operational eco-efficiency (OEE) agenda aims to increase raw material efficiency, reduce energy consumption, and decrease both emissions and the production of waste. The key performance measure is the OEE footprint, a weighted average of nine footprint parameters, including waste production; energy use; direct and indirect CO2, NOx, and SOx emissions; total water usage; and volatile organic compound use. “We started our OEE agenda in 2010 and have been working hard to identify ways to make improvements, share the performance results, and ensure that best practices are implemented across the company,” Morssinkhof says. The AkzoNobel OEE footprint was reduced by 22.5% from 2009 to 2015 (audited by KPMG).

Like Eastman, AkzoNobel has an executive committee with overall responsibility for sustainability. The company also has a sustainability council that advises the executive committee on strategy development, monitors the integration of sustainability into management processes, and oversees the company’s sustainability targets and overall performance. “Our biggest challenge is the battle for focus,” states Morssinkhof. “We have a lot of requirements to improve the performance of our plants, including process safety, boosting productivity, and making sure we can produce sufficient quantities of product of the right quality at the right moment for our customers.” Lucore agrees: “The time, effort, and investment behind advancing production technologies are enormous and only worth it if outcomes have great ROIs and are scalable. Each innovation must go through extensive stages of research, development, piloting, and testing to prove that implementation will result in appreciable impact reduction and cost savings. In addition, before any great idea can even begin, government support and funding and partnering with universities and researchers are required.”

Reference

1.    Anastas, P.T. and Warner, J.C., Green Chemistry: Theory and Practice, Oxford University Press, New York, 1998.