EDEN v Pyrolysis
Often we get questions or statements resembling “Is this like pyrolysis?” or “This is just a more complicated pyrolysis”, and the simple answer is No to both accounts. When comparing industrial processes there are many factors to consider, operating temperatures, pressures, design, complexity, results, and more. When comparing the Eden Energy Process to pyrolysis, to truly understand the difference isn’t a simple explanation, as the technologies only share 1 thing in common, heating material in a pressure vessel (pressurized tank).
In our 3 part series about the Eden Energy Process we went into depth about the magic of the system, the EEP’s process flow, and the products produced (if you haven’t read those it will be helpful to read before diving into this blog as I wont rehash the EEP in immense detail here). So to start this post I will dig into pyrolysis, its history, its process flow, and its products.
Pyrolysis has ancient origins, the word itself has Greek origins “pyro” (meaning fire) and “lysis” (meaning separating). Pyrolysis has been utilized for thousands of years, mainly in the production of charcoal from wood. We have ample evidence and knowledge that a crude, early version of pyrolysis was used by ancient cultures such as the Egyptians and Chinese. Fast forward to the Industrial Revolution, pyrolysis was advanced to be utilized for the production of coke from coal (coke is a carbon-rich substance that was integral to iron smelting). During WWII the German’s used a form of pyrolysis called Fischer-Tropsch to convert coal and biomass into liquid fuels when Germany ran into fuel shortages. After the war, the global petroleum industry “exploded” onto the scene, and pyrolysis was all but shelved until the 1970s oil crisis, it was during this time that many forms of pyrolysis appeared, including slow pyrolysis, fast pyrolysis, and flash pyrolysis - my uncle even helped build one in the 1970s for the US Treasury to dispose of all the old money. All this to show pyrolysis is not a new technology, and with what we know about it today, with the advancements of the EEP, it is time that pyrolysis goes back on the shelf, and below I will explain why.
Pyrolysis is what’s called a supercritical process, meaning the equipment needs to be built extremely robust with pyrolysis temperatures ranging from 1000 (on the low end) to 2000°F (on the high end). This means the equipment is typically very expensive, difficult to build, requires a significant maintenance schedule, and often needs special metallurgy. This makes building a cost effective system difficult right off the bat. The EEP throughout all of its process steps operates in the subcritical range, meaning our equipment is much less difficult to build, and we can use industry standard metallurgy such as stainless or even carbon steel for our tanks, vessels, and reactors. Also, due to the subcritical nature, it allows the EEP to use readily available industrial equipment like valves and tubing (pipes) - in fact, the only custom equipment we have to have produced for our systems are our tanks, vessels, and reactors (reactors are just vessels that have heat applied to them), and only because we need specific locations for inputs and offtakes (where material goes in and out).
Secondly, pyrolysis typically operates under vacuum or atmospheric pressure. This causes some issues, first, compounds like Polycyclic Aromatic Hydrocarbons (PAHs), and heterocyclic carbon rings that are in the waste are typically hard to thermally crack, these compounds do not have a chance to “break” as they are removed from the reactor from the pull of the vacuum before the decomposition (breaking of the bond) of the carbon ring can happen. Second, due to the operating parameters of pyrolysis, a process called cyclization happens, this is where larger carbon structures decompose and form smaller aromatic hydrocarbons (like benzene, a PAH), so not only does pyrolysis not break the PAHs found in the waste, but it causes the formation of more. PAHs are immensely toxic, strong compounds, and while they can be removed from fuels, this is an immense energy cost, that significantly reduces the feasibility and energy efficiency of pyrolysis. This leaves 2 options for pyrolysis, leave the PAHs in the fuel and burn it as is (which you would not be able to operate this type of facility in states like NY and CA who have strict emission laws), or spend the energy to clean it up (which would plummet the systems efficiency and ROI). The EEP operates under pressure in every stage, and the hydrogen shift reactions which are mentioned in the EEP Part 1 blog, break these carbon rings, ensuring our fuels are free of not just PAHs, but all aromatic hydrocarbons without additional processing. This is one of the key reasons why the EEP has achieved third party validation of over 90% energy efficiency.
Third, speaking of energy efficiency, due to the immense temperatures and because of the many pre- (Sorting, drying, particle size reduction, etc) and post processing steps (Product quality control) needed for pyrolysis, its efficiency is often quite low (between 40-60% - often even below 40% to create usable products) leading to poor ROIs. This is due to several factors with the largest being that pyrolysis, as mentioned, operates under supercritical temperatures, this means a significant amount of energy is required to bring the material up to operating temperatures, A LOT of energy. Then to top it off all the steps needed just to get into the process (drying especially as water is the “enemy” of pyrolysis) consumes A LOT of energy, and again, the steps needed to clean/refine the products produced from pyrolysis so they don’t create even more pollution is immense. Now many might be saying, well if it gets rid of waste, it shouldn’t matter if its efficient, and in a perfect world they may be right, but this world is anything but perfect. For a product to have mass adoption you must be able to yield a positive return from it. If you can’t make money on it, only municipalities (who can just raise taxes) or immense government funding can keep the organizations operating these systems bottom lines in the black (at least for the systems, but no body wants to invest into a money pit). That is just not a reality and one of the main reasons why mass pyrolysis adoption has not taken place. This is an area where pyrolysis just doesn’t come close to comparing. The EEP, once again, do to its subcritical temperatures and pressures, as well as advanced process loops, as mentioned has been third-party validated over 90% efficient, and with the latest advancements to the technology, including the use of modern solar panels, the EEP has the potential to be a net energy producer and bring our energy efficiency over the 100% margin. The EEP has minimal pre-processing steps, removal of large pieces of metal (to prevent wear and tear of equipment) and particle size reduction (to increase surface area and allow for easier product transfer through the system). The EEP utilizes steam as its heat source, meaning we don’t cool/condense waste steam, we recycle it in various process loops for preheating. And finally, because of the effects seen in our hydrothermal liquefaction steps, the finished products of the EEP are not only pure, but cleansed of all harmful compounds - making our fuels the cleanest burning hydrocarbons, period. Our fuels are almost entirely carbon and hydrogen - two of the most abundant elements on the planet.
Fourth, pyrolysis is typically a 3 stage process, which consists of pre-processing (particle size reduction, drying, and sorting), the pyrolysis process itself, and energy production from the fuels, but pyrolytic products are often immensely toxic. As mentioned, pyrolysis does not operate under pressure - so all the harmful compounds in the fuels that we discussed above, become airborne after the fuels are combusted for the energy, but it is not just PAHs, and heterocyclic compounds. As pyrolysis does not pretreat wastes, any harmful compounds such as heavy metals, dioxins, furans, VOCs, etc. that are found in the wastes are now in your fuels as well, and become airborne when the fuels are combusted, as well as in the biochar produced from the process. Pyrolysis, is also not a waste free process, and the byproducts (Tar, residual ash, etc) are often extremely toxic and loaded with an abundance of "bad actors". The Eden Energy Process is an 8-stage process, where the wastes undergo 2 separate reactions utilizing water under pressure, which allow us to remove the harmful compounds and criteria pollutants in a safe and proven method, before going into our thermal cracking pressurized stage where the harmful carbon rings are broken. Eden fuels are clean-burning, and carbon-neutral, free of the criteria pollutants and harmful carbon chains found in pyrolytic and traditional hydrocarbon fuels. Also, due to the nature of the process, there is no waste stream in the EEP as all materials are converted into a useable form.
Ultimately it is due to the above factors, we can make the argument that pyrolysis does not solve the pollution issue, it simply displaces the pollution. Instead of being bound in the form of plastic, or other feedstocks, those wastes are converted into fuels, which directly inject the harmful pollutants into the atmosphere. While pyrolysis clearly works from the prospective of can it make fuels from waste, it is the costs that makes it harmful on a full lifecycle analysis. The EEP, with its lower operating temperatures, efficient resource utilization, and clean output, stands out as a more technologically advanced and environmentally positive alternative.
In conclusion, the EEP's innovation lies in its ability to operate under subcritical conditions, which not only reduces the energy input required but also eliminates the formation of toxic byproducts. This results in a higher energy efficiency and cleaner fuels, free from harmful pollutants such as PAHs and other aromatic hydrocarbons. The EEP’s advanced process design ensures that all materials are converted into usable forms, eliminating waste streams and enhancing overall sustainability.
By harnessing these technological advancements, the EEP provides a superior solution for waste-to-energy conversion. It not only addresses the inefficiencies and environmental drawbacks of pyrolysis but also offers a scalable and economically viable alternative (in some locations the ROIs are insane - looking at you California). As we look towards a future where sustainability and clean energy are paramount, the EEP holds the promise of creating a cleaner, healthier environment while contributing to global energy needs. This is the future we can create with the EEP—one where waste is transformed into valuable resources without compromising our planet’s health!
The Future will be Green
The Future will be Pristine
The Future will be… Powered by Waste!
Jonathan Appel
Founder and CEO
