Nonwovens | Pulp & Paper | Renewables
Consulting services to support project development, technology selection, new product development,
due diligence, market intelligence and new business development.
Biorefineries, Biomaterials and the Nonwovens Industry
by Alexander A. Koukoulas, Ph.D.
Excerpts of an interview which first appeared in Sustainable Nonwovens Magazine (November 2019).
At the EDANA Outlook conference in October, 2019, you spoke of the three generations of biorefinery production. Can you briefly outline them? Biorefineries are function of the type of feedstock they are using and the process technology they deploy to transform biomass into valued-added chemicals. In terms of feedstocks, 1st Generation biorefineries use starch and sugars derived from plants. An excellent example of this is corn-based ethanol, which uses starches derived from corn to produce ethanol through fermentation of the corn-based sugars. Virtually all commercial bio-based materials, such as polylactic acid or PLA, rely on the fermentation of plant-based sugars.
In contrast, 2nd Generation biorefineries use wood, purpose-grown energy crops, such as switchgrass, and waste materials, such as straw and stover. Currently, there is considerable interest in the United States and elsewhere to use municipal solid waste or MSW to produce value-added fuels. The challenge with these materials is that they contain lignin, which is now seeing some interesting applications, such as a replacement for phenolic-based resins. Removing lignin and accessing the cellulose component of these 2nd generation has become quite a technical barrier, although considerable research efforts are on-going.
3rd Generation biorefineries are based on algal systems or look to utilize atmospheric carbon dioxide directly. These technologies are generally early-stage although there are some demonstration projects underway. In terms of benefits to the environment, 1st generation biorefineries are generally an improvement over the baseline, that is existing petroleum-derived options. For example, corn-based ethanol has about a 20-30% reduction in greenhouse gas emissions over petroleum-derived gasoline. Of course, the push-back to 1st generation biorefineries has been the fact that they may compromise the available of food resources and that they may have negative impacts from land-use, such as deforestation. Because of the choice of feedstock, 2nd generation biorefineries have greenhouse gas reduction that are great than 60% over the baseline. Whereas 3rd generation technologies, can have reductions that are greater than 100%, as they can actually sequester atmospheric carbon.
The emphasis, however, has so far been on the production of biofuels, rather than bioplastics. Why?The emphasis on biofuels rather than bioplastics is due to regulatory factors. In the United States, the Renewable Fuels Standard (RFS) sets minimum levels for bio-based ethanol and diesel fuels. A fuels identification and trading system has been developed to enable the RFS. In Europe, renewable fuel standards have also been set around atmospheric carbon dioxide emission targets, which impose taxes should these targets not be met. With clear rules of the road in place, an industry has grown. Prior to the introduction of the Energy Independence and Security Act (EISA) of 2007, which created the framework for the RFS, ethanol production in the United States was about 5 billion gallons per year. Today, it is over 16 billion gallons per year. For producers of corn-based ethanol, this has been a great success story, at least from the standpoint of capacity increases. However, there are no such drivers for the bio-plastics industry. The carbon tax, which could have been a driver for bio-plastics, has generally failed in the United States. As a result, bio-plastics must either compete with petroleum-derived plastics in terms of price and performance, or provide additional performance benefits that make it the preferred material of use. That being said, new legislative efforts, such as Single-use Plastic (SUP) bans and consumer demand for move environmentally-friendly materials should be a big driver for bio-based plastics in the future.
Yet, how successful have biorefineries for biofuels been? First generation biorefinery capacity has seen tremendous growth over the last 10 or so years, both in fuels and chemicals. On the other hand, the United States has made enormous investments in the pursuit of second-generation biofuels derived from lignocellulosic sugars, motivated by their inherently low-cost, the potential for drastically reducing carbon emissions and the promise of job creation, especially in rural communities. Unfortunately, while significant technical progress has been made, they have yet to achieve commercial viability due to their inability to compete with conventional fuels on price. However, there are a number of 2nd generation biorefinery platforms in the queue, that if successful, would transform the state of readiness for 2nd generation technologies.
What has been the reaction to this from researchers and developers? When looking at the business case between fuels versus chemicals, clearly fuels are advantaged, especially when it comes to large-scale production platforms. As a result, considerable research has focused on the production of drop-in fuels from biomass. In terms of 2nd generation technologies, many of the demonstration projects are focusing on drop-in jet fuel replacements. The aviation industry has set a number of ambitious goals for greenhouse gas reductions, and they see bio-fuels as being part of an overall solution to this challenge.
So who is successfully manufacturing bioplastics on any kind of scale? Clearly, there are a number of very successful manufacturers of bio-plastics, both the so-called “substitute variety”, like PLA, and the “drop-in” variety, such as bio-based polyethylene (PA). The range of options, bio-based, biodegradable, compostable, is becoming very confusing, especially to consumers who are faced with responsibly disposing of these materials. From the standpoint of substitute bioplastics, starch-based materials, such as thermoplastic starch, and PLA, are proven platforms with large scale. These are success stories long in the making. Other substitutes are coming on stream but their capacity levels are low and their processes are generally unproven. On the other hand, drop-in bio-plastics represent nearly 60% of the bio-plastics market, and a number of producers for bio-based PE, polyethylene terephthalate (PET), and other commodity plastics, are on-stream and commercially available.
Do you think products containing only partial bio content, ie Coca Cola’s PETBottle, add confusion, or are they a necessary step-wise development? Use of bio-based plastics begins with a thoughtful look at strategy and deciding what problem or consumer need you are looking to solve. Using drop-in solutions, like bio-based PE, may help reduce your carbon footprint, but they won’t necessarily solve the problem of marine plastic pollution or the problem of micro-plastics in the environment. In addition, many users of bio-based plastics are not especially candid with their life cycle assessment data so can sometimes be difficult to argue the exact benefits of their solution. The confusion many of these products are adding to is at the point of recovery and recycling. For example, bio-based PET, which typically contains only 30% bio-content, disrupts the conventional PET recycling stream. Do I really want to be producing a boutique material? To my clients looking to adopt bio-based plastics, I always ask: What problem are you trying to solve?
What will it take for attention to fully move to focus on bioplastics legislation? The three big drivers for bio-plastics are legislation, consumer demand, and the response of brand owners to meet the growing demands of the both regulators and consumers. I think it’s fair to say that consumers are becoming much more aware of the health of the environment, factors effecting climate change, and the choices they are making to off-set these factors. Governments are certainly listening to their constituents and creating legislative frameworks that can achieve positive change. Perhaps, some of the global initiatives under the Paris Accords are taking a backseat because of the current political climate in the United States. However, this has not prevented countries, the European Union, and states, such as California, from taking bold stands on the environment. Since a global framework for carbon valorization has largely failed, the drivers will continue to be legislation, consumer demand, and brand owner action.
What stage do you think bioplastics will be at in five years’ time in terms of market size? Given the current level of brand-owner engagement, consumer demand, and legislative efforts, the market for bio-plastics could easily double in the next five years. The growing demand for disposable and flushable wipes, eliminating PE in all laminated foodservice applications, and single-use plastic alternatives are all low-hanging fruit for bioplastics.
And how far do you think those third generation materials will have progressed? If you include certain specialty chemicals, such as omega-3-fatty acids, in the mix of 3rd generation materials, there has been considerable progress. However, the production of commodity-type polymers and resins is still a big challenge. A number of companies are looking to capture both carbon monoxide and carbon dioxide from flue gas emissions and use this as a feedstock but these are still early-stage. There also have been a number of early stage efforts to remove atmospheric carbon dioxide and use this in a catalytic process to produce chemicals. While this is very exciting, it’s hard to imagine that these processes will be available commercially anytime soon.
© A2K Consultants 2019
The Lignin-based Biorefinery
by Alexander A. Koukoulas, Ph.D.
Chemicals and chemical feedstocks from lignin are benefiting from heightened demand, driven by the unique functionality of lignin-derived chemicals, as well as the increased demand for bio-based materials that can be sustainably sourced. It is our view that the overall demand for fow-carbon alternatives to petrochemical-derived materials is strong and will show continued strength.
Bio-advantaged Chemicals & Materials
Bio-advantaged materials such as precipated lignin and lignosulfonates provide a range of industrial applications as viscosity modifiers and adhesives, and are used extensively in multiple markets. Precipitated lignin and bio-based organics derived from wood and biomass are being used in a number of new applications, including bio-based fuels and resin systems. New applications for lignin-derived materials are replacing petroleum-derived resins, such as urea-formaldehyde (UF) resins used in building materials and acrylonitrile butadiene styrene (ABS) resin systems, a thermoplastic polymer used extensively in the automotive industry.
Aerial view of the LignoTech Florida LLC biorefinery complex on Amelia Island, Florida.
LignoTech Florida LLC
Recently, I had the opportunity to visit one of the largest producers of lignin-derived chemicals—LignoTech Florida LLL, a joint venture between Norway-based Borregaard and Rayonier Advanced Materials—and tour their newest production facility on Amelia Island, Florida.
The LignoTech Florida facility opened in June 2018. The plant leverages the exisiting sulfite pulping capacity of Rayonier’s Fernandina Beach pulp mill with the lignin processing expertise of Borregaard. And, what set’s this facility apart from many is the level of process integration between the old and new plants. Rayonier supplies spent sulfite pulping liquor—a lignin-containing feedstock—to the LignoTech plant, along with water, utilities, and wastewater treatment. In turn, the LignoTech plant converts the spent pulping liquor into valuable lignin-based chemicals and returns recovered pulping chemicals contained in the liquor to the mill. This reuse of chemicals and the conversion of lignin to valuable chemicals maximizes the value of a material that in the past would have been burned for its heating value.
A Model for Biorefineries
We see the LignoTech Florida LLC project as being a model for biorefinery producers and manufacturers alike. Leveraging infrastructure, turning waste streams into valuable products, and fostering cooperation between companies and local communities are powerful lessons for companies and project developers looking to follow this example.
© A2K Consultants 2019
The Bioeconomy Downunder
by Alexander A. Koukoulas, Ph.D.
While the bioeconomy in the United States faces an uncertain future, other parts of the world are rapidly expanding initiatives to strengthen their bioeconomy industries. Take, for example, the Down Under State of Queensland. This coastal State in Australia has outlined a very ambitious goal to leverage its comparative advantages in geography, agriculture, and an advanced workforce to become a center for the production of bio-based fuels and chemicals.
Expression of Interest
Recently, the Government of Queensland announced an invitation to bioeconomy developers to submit an Expression of Interest. The State is welcoming developers interested in developing manufacturing capabilities in Queensland to express their intent. The State will leverage its considerable resources to support development with the State, including direct financial support.
Queensland - Australia's Bioeconomy Center
Queensland, the second-largest state in northeast Australia, has an emerging industrial biotechnology and bioproducts sector that is eager for growth. The State has clearly articulated its commitment to the bioeconomy in a detailed strategic plan that provides a framework for development and commercialization, including the creation of a Biofutures Industry Development Fund, a competitive funding pool to assist companies with reaching bankable feasibility. In addition, the State has worked to establish a robust feedstock infrastructure including sugarcane, agricultural and forestry waste, as well as sweet sorghum. This has lead to some early successes including three commercial biorefinery plants producing ethanol from molasses and sorghum and bio-diesel from animal fats and oils.
While current mandates for renewable fuels are relatively modest—gasoline contains 3% ethanol, increasing to 4% in 2018—the intent is to both increase domestic targets and grow exports. Moreover, the State embraces the idea that the world is on the verge of a bioeconomy transition that will drive demands for bio-based chemicals. State officials look to World Economic Forum (WEF) predictions for biomass-derived fuels, energy, and chemicals to generate at least $230 billion to the global economy by 2020 and they are committed to be a participating in this value creation and realizing at least $1 billion in new economic activity in this sector within this time frame.
The State seems to be taking a broad view of the bioeconomy under the “Biofutures” framework, which refers to all segments of the industrial biotechnology and bioproducts sectors. Any innovative approach to converting sustainable organic and/or waste resources, rather than fossil fuels, is considered fair game. The State is encouraging the development of new feedstock value chains including: macro- and micro-algae, plantation forestry, and carbon-rich waste streams. Desired outcomes include the expanded production of bio-based chemicals, fuels, synthetic rubber, cosmetics, detergents and textiles.
Why Queensland?
Queensland has a subtropical and tropical climate providing ideal conditions to produce a range of feedstocks with high yields on a year-round basis. Specifically, the ability to competitively produce some of the world’s most energy-dense and productive feedstocks such as sugarcane, eucalypts and algae. Additional feedstock includes red and sweet sorghum, native grasses, crop stubble, cassava, agave, and pongamia.
A mature and modern agricultural industry with well-established supply chains from farm gate to markets.
Connection to international markets through reliable and efficient infrastructure, including 7 bulk shipping terminals.
Ideal positioning at the gateway to the Asia-Pacific and close economic ties with expanding Asia-Pacific markets.
The State is also offering numerous incentives to stimulate investment in the bioeconomy sector, including the Biofutures Industry Development Fund, a repayable fund to help well-advanced industrial biotech proponents to get large-scale projects through the final stage of financial due diligence to secure financing from investors.
Interested in developing projects in Queensland? The deadline for submitting an Expression of Interest is January 18, 2017. Please contact us for additional information.
© A2K Consultants LLC 2017
A Critical Look at Cellulosic Ethanol and Other Advanced Biofuels
by Alexander A. Koukoulas, Ph.D.
Over the last 10 years, the United States has made enormous investments in the pursuit of bio-based fuels the so-called “Second Generation” or 2nd Gen biofuels. Unlike 1st Gen biofuels—ethanol from corn starch—2nd Gen biofuels are derived from lignocellulosic sugars, those that come from woody biomass and agricultural sources, such as corn and wheat stover, and purpose-grown energy crops, like miscanthus and fast-growing poplar.
The pursuit of 2nd Gen fuels has been motivated by several factors including: their inherently low-cost, at least from a theoretical standpoint; their potential for drastically reducing carbon emissions relative to 1st Gen Fuels; national security (less dependence on foreign oil); and job creation, especially in our rural communities.
Unfortunately, while significant technical progress has been made in the last decade, 2nd Gen fuels, especially those produced using biochemical platforms, have yet to achieve commercial viability due to their inability to compete with conventional fuels on price. In fact, several years ago, researchers and developers alike recognized these technical challenges and began shifting their focus from lignocellulosic ethanol to “drop-in” fuels, such bio-butanol, in the hope that enhanced compatibility with the existing liquid fuels infrastructure would make these fuels more cost competitive.
It should come as no surprise that these technical and commercial challenges have not gone unnoticed from a policy perspective. Delays in achieving widespread commercial success has had significant impact on the entire renewable fuels industry. An extensive analysis from the Government Accountability Office (GAO) issued last month stated that “the investments required to make these fuels more cost-competitive with petroleum-based fuels, even in the longer run, are unlikely in the current investment climate.”
To better understand the current state of biochemical-based production pathways, we reviewed recent developments in the production of 2nd Gen biofuels produced under a number of biochemical routes. Our intent was to provide a state-of-the-art assessment of progress of advanced biofuels within three market applications: gasoline, middle distillates and aviation fuels (see table below).
Particular attention was paid to the success rate of genetic engineering and their commercialization prospects. What we found was that in spite of the significant progress made in the genetic engineering of microbes designed for advance biofuel production, titer and yield of these biomolecules are currently too low to allow these products to compete with their petroleum-derived equivalents.
What surprised us was how far off we are relative to corn-based ethanol. For example, the highest reported yield for the best available alternative to starch-derived ethanol (iso-butanol derived from engineered E. Coli, is still one-eighth the level of achieved in the production of fuel ethanol from corn using that industrial workhorse, S. cerevisiae (see figure below). Moreover, high titers and yields from alternative routes are always reported using model sugar substrates, like glucose, not real-world hydrolysates derived from cellulosic biomass. Neither wild-type nor genetically-engineered microorganisms have been isolated or developed with all the necessary traits for the bulk production of advanced biofuels. And, unlike yeast and conventional ethanol fermentation, recycling of microbial cells are difficult in a lignocellulosic system and genetically engineered strains seem highly susceptible to contamination, which further increases operating costs.
Of course, upstream challenges with cellulosic ethanol are not completely solved either. Recovery of sugars at high concentration from a highly water-holding (hydrophilic) substrate is still challenging. And, the downstream challenges with fermentation are multi-fold including: the toxicity of the inhibitors to both microbes and enzymes; conversion of multiple sugars; and, enzyme and microbe recycling of the enzymes.
As a result, attention was refocused from cellulosic ethanol to other fuel types, such as cellulose-based butanol, fatty acids, and isoprenoids. Based on current progress, it is evident that these also will not be commercially viable as the inherent complexity of micro-organism development for these pathways continues to present formidable technical barriers. Moreover, development is expected to be painstaking as the challenges with microbes used in these systems are multi-fold higher compared to even cellulosic ethanol.
The question of inhibitors still presents an on-going challenge. As is well known, along with the presence of multiple sugars, lignocellulosic hydrolysates contain a spectrum of compounds, which are potentially toxic to the enzymes and/or microbes used in the bioconversion process. These toxic compounds or inhibitors are both naturally present in the lignocellulosic substrates and also process derived including the toxicity imparted by the final products. Techniques for in situ removal of inhibitors and strategies that can enhancing titer, such as gas stripping and solvent extraction, while marginally effective were found to add significant cost to production.
It has been suggested that the cell membrane is the primary target of toxicity as most of these molecules has been shown to fluidize the cell membrane. Increased membrane fluidity also results in uncontrolled transport of solutes that can decrease the proton flux across the membrane and cause leakage of amino acids and enzymes. Over-expressing products that are inherently toxic to the cell membrane appears to be the greatest limitation in achieving high yields. Despite extensive research efforts, there has been limited success in developing a commercial microbial strain for producing advanced biofuels that is both multiple-sugar consuming and inhibitor tolerant while obtaining an industrially acceptable titer and yield. As a result, substantial R&D in metabolic engineering and optimization will be needed to develop a suitable microbial strain capable of producing advanced biofuels from lignocellulose.
We concur with the GAO that lignocellulosic ethanol is far from being commercially viable given the present state of the technology, the unfavorable economic conditions and the policy uncertainty. We also seriously question the commercial viability of certain “drop-in” fuels. Imparting microbial cells with numerous and often competing functions without interfering with their basic physiological characteristics remains a formidable challenge. Key success criteria, like product yield, are still far from commercially relevant levels. Adding the complexity of the cellulosic substrate just raises the technical hurdle for commercialization.
The potential for expanding 1st Gen ethanol as a fuel and as a feedstock for chemicals production is enormous. In most cases, commercialization hurdles are a question of policy rather than technical readiness. However, with respect to 2nd Gen biofuels, only a renewed commitment to basic R&D can provide the tools needed to bridge the many technical gaps that stand between the current state and commercial success. Clearly, the need to fund R&D programs will be a difficult argument to make given the current economic and political climate. But, it is possible if a broad, strategic view is taken. The alternative—widespread defunding of programs—will be a huge set-back. As for commercial opportunities, given this analysis, only value-added specialty chemicals—those that are differentiated from their petroleum analogues—have the potential to be commercially viable at least in the short run.
References
GAO-17-108. Nov 28, 2016. DOI: Nov 28, 2016.
This article first appeared in the Thought Leadership section of Biofuels Digest on December 12, 2016.
© A2K Consultants LLC 2017
Going Beyond Infrastructure
by Alexander A. Koukoulas, Ph.D.
In the first 100 days of a new Trump administration, we should expect to see the passage of a $1 trillion infrastructure bill. This should be welcomed news to many who have witnessed the neglect and decay of our critical infrastructure: our transportation networks and utility systems.
No one will argue that our infrastructure warrants major upgrades. Repairs to our bridges, roads, power and water systems will be of great benefit and we should not delay in executing these projects. While this will provide a short-term shot in the economic arm, we also need to consider the investments that will be required to make the U.S. more competitive and provide a sustainable basis for job creation in the long-term.
The positive relationship between a country’s R&D spending and its productivity growth is well-documented. Investment in R&D provides the innovations in science, healthcare, and engineering that define the new technology and manufacturing platforms of the future: platforms that create the jobs of the future, drives productivity, enhances our well-being and increases our standard of living.
Sadly, a recent assessment by the American Association of the Advancement of Science shows that federal R&D spending as a percentage of GDP has declined from 1.23% in 1976 to 0.78% in 2016 (see figure). In stark comparison, China now spends over 2% of its GDP on R&D, up from less than 0.6% in 1996. If the U.S. is to maintain and enhance the standard of living of its citizens, if it intends to create the jobs of the future, it must create a climate where R&D investments, both public and private, are seen as “strategic” investments. To this end, it would be tragic if our stimulus in infrastructure leads to further erosion in our investment in R&D and innovation.
As a nation, we must recognize the link between the investment in R&D and the long-term benefits it makes to our standard of living, national security and global leadership. This has helped make the U.S. the most dynamic economy in the world. In planning for the future, let’s not forget what has driven American progress and let us work to place renewed priority on R&D investment.
© A2K Consultants LLC 2017
Torrefaction: A Pathway Towards Fungible Biomass Feedstocks?
by Alexander A. Koukoulas, Ph.D.
In June 2016, I gave an invited talk at the Advanced Bioeconomy Feedstocks Conference, which discussed the potential of low-cost forest biomass resources for accelerating the growth of the bioeconomy. My central theme focused on the availability of at least 68 million dry tons of forest residuals that could be sustainably harvested and used in the generation of biomass power and bio-based chemicals. Add to this at least 60 million dry tons of forest biomass that could be sustainably derived from forest management programs conducted on our National Forests and the amount of inherently low-cost biomass resource that could be used to drive the bioeconomy is enormous.
As with most biomass sourcing scenarios, forest biomass is challenged by the added cost of aggregating, handling, delivering and storing relatively low-density material across the supply chain. Compounding these challenges is the relatively high heterogeneity of the material in terms of its moisture content, chemical composition and energy density.
One promising approach to overcoming these challenges is torrefaction, a mild pyrolyis process that removes low-grade volatile materials from biomass to produce a relatively uniform energy carrier that can be used as a solid fuel. When densified, the energy density of torrefied biomass approaches the energy content of low-rank coal. An added benefit is that torrefaction imparts water resistance to the material, thus obviating the need for expensive storage solutions. The result is a bio-based energy carrier that can be used as a drop-in replacement for coal. While the U.S. is rapidly phasing out coal-fired power generation facilities, the opportunities for using torrefied biomass in existing coal-fired facilities, in either “super-peaker” or co-firing modes are enormous. Of course, export markets, like the EU, are especially excited about torrefied biomass as it has the potential of lowering transportation costs and dramatically reducing expensive capital improvements that are typical in non-torrefied biomass power generation.
Torrefaction removes water and low-energy volatiles from wood to create a water-resistant energy carrier with high energy density.
Biomass power generation is the only renewable option that can provide dispatchable, baseload energy delivery. Driving out cost through torrefaction could expand its use and adoption. Beyond power generation, torrefied biomass is finding applications as a specialty material, such as a component in advanced composites. Recent technical advances in torrefaction process technology and market demand for this material could drive a whole new industry based on renewable biomass resources.
DOI: June 16, 2016 © A2K Consultants 2016
Wet-Laid Forming in Nonwovens: Where Do We Go From Here?
by Alexander A. Koukoulas, Ph.D.
At the Research, Innovation & Science for Engineered Fabrics (RISE® 2016) Meeting sponsored by INDA, I had the pleasure of speaking about the the production of nonwoven composites using wet-laid forming technologies, and providing thoughts about its future growth. For industry outsiders, most nonwovens are manufactured using either one of two main process technologies: dry-forming and wet-laid forming. The latter is a smaller subset of the two and is based on conventional papermaking process technologies. At its most fundamental level, wet-laid forming can be viewed as dewatering process wherein a dilute mix of fibers in suspension is transformed into a paper-like web. Products made using wet-laid forming include industrial papers, such as Nomex® paper and glass mats, and consumer products, such as disposable wipes. Highlights from this invited talk are presented below.
Wet-laid forming provides a high degree on freedom for fiber selection, additives and functional chemicals that can be used to create an array of engineered nonwoven composites to meet the demands of range of downstream applications.
Nonwovens Market. The world of nonwovens represents a rapidly-growing $37 billion industry, delivering a range of product solutions that can meet the strictest of industrial and consumer demands. Nonwovens are ubiquitous—from personal hygiene products to automotive fabrics and filtration media—they are found in almost any product and market segment. And, the industry is growing, both organically and through the introduction of novel products that can meet the consumer demands of tomorrow.
Multiple Degrees of Freedom in Material Selection. From a new product development standpoint, the multiple degrees of freedom in wet-laid nonwovens design and engineering opens the door to product innovation and the development of unique differentiated products to meet consumer needs. Nonwoven products leverage a rich palate of materials options, including fibers, pigments and specialty chemicals, as well as a range of process delivery options, including former design and the addition of specialized unit operations such as hydroentangling systems, in-line coaters and calendering. From a materials selection perspective, nonwovens can be engineered from a range of material types including: natural and synthetic fibers, binder systems, inorganic fillers and catalysts. And, unlike dry-laid forming, wet-laid forming can use a range of high-performance staple fibers, such as aramid and carbon fiber, to develop unique products with exceptional utility. Lastly, wet-laid forming can leverage the hydrogen bonding potential of natural fibers to create lightweight materials of exceptional dry strength, while maintaining their ability to disperse upon rewetting. This explains the increasing use of wet-laid manufacturing platforms to produce consumer products, such as disposable wipes.
Improved Process Technologies. From an engineering standpoint, improvements in wet-laid forming technologies have been substantive enabling the deployment of machines with unprecedented scale. The largest papermachine in the world is 428 meters long, 11 meters wide, with operating speeds of 2000 meters per minute. Clearly, scale and the technologies that support scale, such as pressurized head box design, polymer-based machine clothing, extended-nip forming technologies, synchronous drives and machine control systems have contributed to impressive advances in productivity. This, combined with advanced water saving technologies, give wet-laid forming processing significant economic advantages over competitive forming types in certain product applications.
Demand for “Green” Products. Consumer expectations are shifting towards products that can mitigate environmental impact and those derived from sustainable, renewable resources. For example, at least 15 states and the District of Columbia have placed severe restrictions and in some cases outright bans of the sale of plastic bags. In this regard, expanded use of short natural fibers in the production of both consumer and industrial products alike will continue to drive the expanded use of wet-laid forming.
Expanding Population Growth. The world’s population is expected to increase from its current 7.4 billion to over 9.0 billion in 2050. While the percentage of younger individuals (age 19 or less) will decrease, the population of those over 65 years of age will significantly increase. An aging population will bring about demands for new products and specialized services. In addition, a rising middle class will present opportunities for product growth across all segments, especially in food packaging and consumer products. Moreover, secular trends that place increasing importance on sustainability and wealth creation, including a rising consumer class in developing countries, will be strong catalysts to a growing demand for nonwovens products. As a result, market opportunities for nonwoven products are expected to remain strong.
On the Horizon. There are many exciting new technologies under development that have the potential for redefining wet-laid forming, improving efficiency and performance, and making it more cost competitive. For example, foam forming technology, which can displace up to 80% of water used in the manufacturing process, is seen as a real opportunity for both transforming the cost of production and imparting novel product properties, such as higher bulk. Wet-laid forming is ideally suited to incorporate nanocellulose, a new class of renewable materials with exceptional strength. Wet-laid forming combined with the in situ production of nanocellulose opens up tremendous opportunities for the development of novel composite structures and coatings.
In summary, wet-laid forming is a well-established technology. As such, it presents little technical risk to project developers looking to expand their product lines, especially in growing market segments such as consumer products and disposable wipes. Technology barriers, such as high water intensity, have been largely eliminated and machine configurations benefit from large economies of scale. Wet-laid forming provides new product developers with exceptional degrees of freedom that can enable the design and production of composites using a range of high performance fibers. It provides a platform for expanding utilization of natural fibers including nanocellulose in novel product applications, such as battery separators and bio-based composites. As such, wet-laid forming is expected to see expanded growth as a manufacturing platform in both industrial and consumer segments.
Postscript. Since presenting this invited talk, my long-time collaborator, Dr. Martin Hubbe of NC State University, and I published a comprehensive review of wet-end chemical approaches to wet-laid nonwovens manufacturing. In this review, we discuss scientific advances in the field and discuss the many strategies for optimizing wet-end chemistry and the various process technologies used to produce nonwovens. Although both synthetic and natural fibers are considered, emphasis is placed on applications where cellulosic fibers are a significant component of the nonwoven product, such as dispersable wipes. Topics covered include: fiber properties and surface chemistry; fiber dispersion; hydroentangling (spunlacing); and foam forming. This article appears in the May 2016 issue of BioResources. To obtain a full PDF copy of the article, click here.
© A2K Consultants LLC 2016