Category Name (FAQ)
Is your steam reforming process a type of gasification process?
Yes, our ‘Steam/CO2 Reforming’ process is a subset of the broader class of gasification processes. In our case, we do not use oxygen or air in the process, which is common in gasification processes. Our process is a reductive chemical reaction wherein oxygen is actively excluded from the process and steam included. This avoids hotspots, tar and slag buildup common to gasification processes. Lastly, there are no catalysts used in the front-end of the Raven SR™ systems.
What can you process?
We can process a wide range of waste, from municipal solid waste to industrial waste, raw sewage, medical waste, creosote contaminated wood, animal waste and carcasses, bio-waste, such as wood chips or agricultural waste – the list goes on (see table below). We can also process natural gas and theoretically coal. Regarding metals, we cannot process these into fuel, however, metal will drop out of the steam reformer, and be sterilized and disposed of or recycled. A high metals content impacts the use or disposal of our biocarbon (15% of process weight,) therefore, any removal prior to ‘Steam/CO2‘ reformation protects that aggregate which can then be sold as a valuable carbon source.
Variety of feedstocks:
- Biomass from fields
- Household garbage
- Paint and solvent waste
- Military classified waste
- Kevlar waste
- Pharmaceutical waste
- Biotoxic organisms
- NASA astronaut harvest
- Renew activated carbon
- Wood and scrap waste
- Electronic waste
- Cleaning chelate solvent
- Silicon water cleaners
- Decon creosote soil
- Used sheep dip
- Radioactive contaminated waste
Why are synthetic fuels better for the environment?
Synthetic fuels are created using renewable energy sources which emit little to no greenhouse gases during production. As a result, there are fewer carbon emissions compared to fossil fuels. If the process of producing synthetic fuels is powered by renewable energy sources, the resulting fuels can be considered carbon-neutral.
Synthetic Fischer-Tropsch (FT) fuels are considered superior to “typical” petrochemical fuels in several ways. Here are a few reasons:
- Cleaner burning: Synthetic FT fuels burn much cleaner than petrochemical fuels, producing fewer emissions of harmful pollutants such as nitrogen oxides (NOx), sulfur oxides (SOx), and particulate matter (PM). This makes them a more environmentally friendly option.
- Renewable: Synthetic FT fuels can be made from a variety of renewable sources, such as biomass and waste materials, reducing reliance on fossil fuels and decreasing carbon emissions.
- Consistent quality: The production of synthetic FT fuels is highly controlled and can be tailored to produce fuels with specific properties and characteristics, resulting in a more consistent quality product.
- Higher energy density: Synthetic FT fuels have a higher energy density than petrochemical fuels, meaning that they contain more energy per unit volume or weight. This makes them a more efficient fuel for transportation.
- Lower freezing point: Some synthetic FT fuels have a lower freezing point than traditional petrochemical fuels, making them more suitable for use in cold environments.
Overall, synthetic FT fuels offer a cleaner, renewable, and more efficient alternative to petrochemical fuels. Raven SR’s process produces a consistently high-quality syngas nearly ideal for FT reactors making it a great option for high-quality fuels locally.
How is this different from bio-fuel technology?
Biofuel projects typically rely upon specifically grown crops or specific agri-based feedstocks. The Raven SR technology is different in that a) it can utilize a wide range of feedstocks, b) it can use waste, including plastics and medical waste, for which a tipping fee may be obtained, c) the system can produce either 99.9999% pure hydrogen, or synthetic Fischer-Tropsch fuels, which are cleaner than petroleum or bio-based fuels.
How is this different from, or better than, pyrolysis?
As used today, pyrolysis has a specific meaning for a series of chemical steps but tend to be applied generally, much like the name Xerox. By strict chemistry definition, pyrolysis is thermal decomposition of organic molecules in the absence of air or oxygen and is usually undertaken for the production of a oil-like liquid from biomass, Steam/CO2 Reforming differs from typical pyrolysis by employing an enabling technology using the introduction of steam and the recirculation of CO2 to control stoichiometry for a given feedstock to promote reforming reactions. With control of its stoichiometry, Raven SR can tailor the composition of a syngas for optimal downstream use in fuels synthesis, or for the production of hydrogen.
If this is so great and has been around for so long, why hasn’t it taken off before now?
Intellergy, Inc., where the technology was developed, was created with a focus primarily on waste elimination, rather than monetization through the creation of fuels. The company sold numerous systems to nuclear power plants and operated a toxic waste elimination facility for the pharmaceutical industry for some time. Typically, these units were sold or spun off. In the mid-2000s, the company entered into a commercially disadvantageous agreement, which stifled growth and prevented development for several years. In 2015, the owners of Raven SR began funding development again, and in 2018, Raven SR acquired the patents of Intellergy.
If this process is such a good idea, then why didn’t someone think of it before?
Steam reforming dates back at least 120 years. It was explored long ago for coal, and later for oil conversion, to produce a gas intended for illumination. The syngas produced at that time contained organic contaminants and had limited commercial applications. With today’s high-temperature alloys and high-tech ceramics, this chemistry was re-examined by Raven SR and new patents were issued which demonstrates how to carry out steam reforming at high temperature and with the proper amount of steam and CO2 to produce a clean, rich syngas.
Are catalyst licenses needed for hydrogen production (the water gas shift reaction) or and for the Fischer-Tropsch syn-fuel process variants?
Are any harmful gases or by-products released in the process?
There will be small amounts of CO2 released, as is inevitable in any process, but we recycle most of the CO2. Air emissions are 2.5 times less than the best available technology, and the process itself has passed California emissions standards.
How big are the units?
Our sites will vary based on production. A site processing 99 tons per day (TPD) as received will be approximately 2 acres and a 300 TPD as received system will occupy approximately 4-5 acres. Our units are modular and skid mounted, and a majority of the site is used for truck turnaround space when loading fuel or unloading feedstock.
Size limitations include the ability to collect and deliver feedstock economically to a processing site.
Is feedstock prep necessary?
To a degree, yes. We can process nearly any feedstock as seen above, but certain feedstocks pollute the bio-carbon residual that drops out during the first stage of our rotary reformer. Aluminum cans, for instance, can go in, but we do not necessarily want aluminum mixed in what should be a pure bio-carbon aggregate. Therefore, a pre-sort removing high-value waste (e.g. aluminum, iron, etc.) and dropping out concrete and rocks will allow for a purer bio-carbon at the end of stage one. Our rotary reformer consists of a commercial “calciner” that is hot, free of oxygen and involves a slanted and rotating tube capable of handling large size pieces (up to 2 inches). As the waste moves from shredder to the rotary reformer, all free oxygen is removed through a CO2 bath inerting the waste so that no incineration or combustion takes place.
To what extent is segregation of incoming waste feedstock necessary? What about water content and other impurities?
Generally, sorting and shredding of MSW/medical is used to remove high-value recyclable materials (i.e. glass, aluminum, etc.) and we assume a working relationship with a waste-management system, such that these costs are carried by them.
Unlike gasification, the high moisture content (50%) is an advantage for us and is near where most MSW is in a natural state. Our process is steam reformation, therefore we would not need to dry the feedstock, and in some cases would add moisture if our feedstock is less than 50%. The gasification processes, on the other hand, requires moisture levels typically to be under 10% which means they must dry feedstocks prior to combustion at a significant financial cost.
Inorganics salts have no effect, but HCl at high levels could, with PVC plastics, etc. The syngas would then be cleaned to ppm levels of sulfur to extend the FT catalyst life.
A high metals content impacts the use or disposal of our biocarbon (15% of processed weight), therefore any removal prior to Steam/CO2 Reformation protects that aggregate which can then be sold as a valuable carbon source.
Describe the difference between “gasification” and “Steam/CO2 Reforming.”
This is a key difference between the Raven SR process and other processes – Gasification uses combustion, while Steam CO2 reforming does not. Gasification is very different chemically and thermodynamically from Steam/CO2 Reforming. While both processes require heat to drive the endothermic chemistry, the source of that heat is significantly different with considerably different results.
Combustion is defined as “any process in which a substance combines with oxygen to produce heat and light.” [Oxford Dictionary of Chemistry] or “Burning (rapid oxidation) of fuel, which releases energy in the form of heat and light, and also releases pollutants (such as sulfur dioxide, nitrogen oxides, and particulates).” [Oxford Reference: A Dictionary of Environment and Conservation]
How is this process different from other competing or similar technologies and projects, some of which have failed?
The Raven SR process is fundamentally different in that it is a reducing chemical process, rather than process of oxidation. The fact that Raven SR’s technology is non-combustion and non-catalytic increases conversion efficiency, allows for a wider range of feedstock, and eliminates many of the problems faced by gasification, pyrolysis and Fisher-Tropsch (FT) projects in the past, as discussed in the following questions.
Raven SR is similar to companies that also focus on a gasification process to create syngas. However, Raven SR’s patented biomass Steam /CO2 Reformation process creates a syngas that is up to twice as rich in hydrogen as competing technologies and lower in contaminants, enabling the production of higher quantities of renewable hydrogen or FT fuels without the maintenance and other issues caused by combustion.
Raven SR is primarily focused on the production of hydrogen, sustainable aviation fuel (SAF) and renewable diesel production from waste. The technology’s ability to produce hydrogen from various waste streams is well established and documented. The market for renewable fuels is growing globally, and Raven SR can produce renewable hydrogen at a lower price than any competitor in the market.
With respect to SAF and Fisher-Tropsch fuels, Raven SR is currently filing new patents on modifications to the traditional FT process, increasing efficiency.
Is the gas produced in the reformer combustible?
The gasses found within the intermediate stages of the process are indeed combustible in the presence of free oxygen or air. Raven SR works closely with its suppliers and carefully engineers its process to prevent the infiltration of air.
Regarding hydrogen, it is combustible, however it actually disperses much more quickly than gasoline. For example, if a containers of hydrogen and gasoline were placed side by side, ruptured and ignited. The hydrogen flame would quickly dissipate, but the gasoline would pool and burn near the container, doing much more damage. In addition, unlike fumes from gasoline or diesel, hydrogen does not add to ozone and it is not toxic.
Do you produce bio-carbon?
Approximately 15-20 percent of the organic fraction of the feedstock (plus any inert materials like dirt, rock, glass and other “tramp” materials) will not convert to syngas in our process. That material drops out as a sterile bio-carbon after our first stage reformer. The material passes the TCLP (“tea-clip”) analysis and is suitable for incorporation into soil as an amendment. Other potential use include production of fertilizer, carbon black, filler for asphalt, or it can be safely used as a filler in concrete.
What are you doing about carbon capture?
A unique element of Raven’s technology is that we are able to recirculate a portion of the available CO2 from the process to optimize and tailor syngas production. The CO2-rich tail gas contains residual energy and hydrogen from the gas separation process. The CO2 from the gas is a candidate for capture and sequestration, or for use in various industries like food and beverage or greenhouses. This tail gas can also be blended with other more energy-dense fuels and combusted for power production. As markets develop, Raven SR is working to develop and monetize this gas stream in the most environmentally benign way.