Trash To Money - Doing Well by Doing Good

Making money from pollution, waste products, and stuff no one wants

In the News

Chemical and Engineering News had an excellent article about cement and concrete. The article is about how making cement releases CO2 emissions, requires an enormous amount of energy, and how there are alternative technologies for replacing some cement with other materials. The one material that is widely agreed upon for replacing cement is fly ash. Fly ash is a common byproduct from the burning of coal and is often stored as a waste product in retention ponds near a coal plant. When retention ponds leak or fail in anyway then local watersheds and ground water can become contaminated. EHS Today has a good article about what happens when a retention pond leaks and gets into surface water systems such as streams and rivers. Cleaning up old retention ponds at coal powerplants could be a source of a raw material widely used in concrete. Government policy could make cleaning up these sites even more attractive (tax incentives? I need a policy expert to weigh in here).

In similar news New York City has started dredging the Gowanus Canal, a superfund site in Brooklyn, New York that has been a place where unfiltered sewage, surface runoff, and a few decades of dumping chemicals back when there were an abundance of factories in cities like New York. I actually used to live about a mile from the Gowanus Canal when I lived in New York and whenever I would run over it on my way to Prospect Park I would try to hold my breath, especially in the summer. The whole area of Gowanus looks like it would be a developer’s dream with some easy access to MTA subway lines and being sandwiched between two affluent neighborhoods in Brooklyn.

The Take Away Here

I put those two stories together because they both represent how cleaning up pollution can unlock value either in creating an abundance of a new raw material that will help prevent CO2 emissions or in how cleaning up a superfund site could revitalize a community and bring value to long time residents. Fly ash was once released into the atmosphere from burning coal along with just about everything else and could create extremely dangerous weather events as shown in Season 1 of The Crown.

Developed countries now have government agencies that regulate our air and water quality. In the United States the EPA was formed in 1970, despite things like the London Fog event happening back in 1952 and people knew it was from burning coal.

If you stop reading here just know that my theme here is that being able to find new uses for what we might consider “trash” right now is the first step towards moving our economy into one that is completely circular.

Trash to Money - The Short Story on Lignin

There is an old saying in green chemistry the forest products communities.

You can make anything out of lignin except money.

What is this lignin stuff you might ask? Lignin is a brownish black substance found in wood that protects cellulose and hemicellulose from fungi and other microorganisms that want to eat the sugar found in the tree. Cellulose is essentially polymerized glucose that fungi and microorganisms would love to eat, but first these organisms have to get past lignin—the tree’s first line of defense.

Lignin is also a polymer, the second most abundant biopolymer on the planet behind cellulose, and is found in many plants but not all of them. The USDA published a really nice overview of what lignin is, where it can be found, the uses of it known in 1969, and how we make pulp through a variety of different methods.

Paper is what we had before we had plastics and to make paper you need to get the cellulose separated from the lignin and to do that you needed a pulp mill. When I was a kid, pulp mills tended to be vilified despite being a major source of economic power in much of the United States. The vilification of pulp mills I believe came from early mills that would dump spent pulping chemicals and lignin into the environment and harvesting trees in an unsustainable way.

Modern pulp mills though are interesting because they theoretically can produce energy on a near zero carbon basis provided they are utilizing well managed biomass that is replaced after it is harvested. The United States Department of Energy has a good article from the Swedish Energy Agency about modern pulp mills, biomass conversion, and how pulp mills could the engine behind a bio-economy of the future.

A modernized pulp mill might look something shown in Figure 1.1 where biomass goes in and cellulose, lignin, and hemicellulose comes out. Lignin and hemicellulose can then be burned to produce electricity and steam instead of being dumped. The pulping chemicals and water get recycled. Other visions for a pulp mill can be seen in Figure 2.4.

These other visions for a pulp mill show how lignin can be converted to chemicals, materials, electricity or fuels. The chemicals used in pulping in these modern mills is recycled back into the process and external fuels can also be biomass derived.

This all sounds great right? Why are we not just running around telling the world about this amazing possibility? Because making anything from lignin is relatively easy, but making money is difficult.

There are only a few companies that can make money from lignin and typically through a select few processes. The first would be lignin to vanillin and the second would be as a concrete additive and there are typically only a few select forest products companies turning a profit here. The biggest and most well known is probably Borregaard. They have their products, which is more than just lignin, in a myriad of end markets. Borregaard has the luxury of having direct access to the lignin waste and the most experience with it.

If Borregaard can make money on lignin and other products coming out of their biorefinery than that should be a model that others can copy including pulp mills in the US and Canada.

Lignum is a company that came onto my radar recently and they are producing fillers and additives for plastics derived from biobased materials including lignin. Lignum is from South Korea and they make lignin products that can be blended into traditional plastics and provide a route to increase the biobased content in the final product. They appear to be still in the start-up phase, but they are already supplying some of their product to automotive manufacturers in South Korea. The concept of putting lignin into automotive plastics is similar to the strategy of Ford in incorporating biobased content into their automotive interior plastics in addition to using partially or near 100% biobased plastics. Lignum recently won an award at JEC Korea for their technology. Since I know my audience skews towards the R&D side, consider reaching out to Oh-Jin Park, if you are interested in sampling any of Lignum’s products. It looks like they have masterbatches of polypropylene and ABS, fillers, and composites that I am told are cost competitive to other bioplastics on the market now.

People saw opportunity to use lignin back in the early 1900s and only about now are we starting to realize those opportunities in the form of societal good, economic output, and easing our own consciences. I’ve worked with lignin by trying to replace chemicals like phenols and bisphenols. It’s not easy, often causes a lot of bad smells, and the end product usually wasn’t as good as what I was trying to replace. Companies that can make money from selling their lignin products should be taken seriously because it is a significant achievement to go against a saying that is almost 100 years old. I hope the saying when I’m older is:

You can make anything out of lignin

Other Wastes To Make Money

Plastics Recycling

I talk about plastics all the time, but some easy problems that need to be overcome would be sorting all of the plastics into isolated streams according to their symbol (1-7) and finding processers that can reprocess that plastic. 12-14% of PET in the US is from recycled material. It could be more and it could be other plastics.

Stone Shot

Ever buy stone wool insulation? I used to work for a company that made the glue that helps hold the stuff together during production. A little known byproduct of stone wool production is called “Stone Shot” and they are essentially tiny pebbles to fist sized rocks that don’t make it to the “wool” part of stone wool. There are mountains of this stuff sitting outside of production plants just getting rained on because it is considered useless. Here is a paper from 2018 on how we might bind this stuff together and make something useful.

Compostable Waste

I’ve talked about composting before, but I think there is a huge opportunity in the country to start collecting compostable waste, turning that waste into compost, and selling that compost back to your customers or to agriculture operations. Outside of your own household compost think about larger scale operations like seafood processing plants, restaurants, grocery stores, and coffee shops. People will pay you to haul away compost, you invest money into turning that compost into soil, and then you get to sell that back into the market. Examples of success can be found here, here, here, here, here, here, and here to name a few.

Here is a good website that shows most composting services by state and where there is a lack of composting services and where entrepreneurs might be able to start-up.

Textiles and Clothing

Where do you put your clothes with too many holes in them? Probably in the trash or if you are good you probably take care of your clothes and donate them when you no longer need them. Either way, a lot of clothing ends up in the trash and then end up in a landfill generating methane, and CO2. Instead there are companies popping up all over that are looking to turn your clothing into new products. My current state of residence Massachusetts has a good resource on how I can recycle my old clothing here. Patagonia has an excellent video about the process of recycling t-shirts and the benefits of making clothing from recycled materials.

Sewage

We flush the toilet and are glad the stuff that was in there is gone. We often do not think about where our sewage goes (unless you have a septic tank) and what happens to it. Someone takes care of it right? Usually someone does in the western world (although see above story about Gowanus Canal). Other countries are not as water rich as others and have had to make decisions on what to do with their waste water. Namibia has been recycling their wastewater since 1968 through using microbes and other separation mechanisms. Here is a good article on how western countries might think about sewage sludge right now. C&EN has a good article from 2017 on new research into how to separate and utilize sewage sludge—some of that technology may be ready for commercialization right now.

You can’t solve a problem unless you understand it

Tony

Share The Polymerist

The views here are my own, do not represent those of my employer, should not be considered investment advice, and before using any chemical you should read and understand the safety data sheet.