chemeng
5 hours ago
This is really cool, I know a few different teams that have taken a look at similar approaches over the last 20 years, I hope you're able to make it work! I've been wanting something like this to succeed for a long time. Please take these questions (and assumptions) as earnest curiosity. I realize you may not be able to share answers if it touches anything proprietary.
On the chemistry side: In step 1, you say using adsorbents, so i'm guessing some combo of iron oxide to desiccant to activated carbon for the siloxanes, and then maybe ZnO (based on your likely catalyst chemistry). At typical anaerobic biogas H2S concentrations, that's quite a bit of OPEX for media I imagine, and the risk of some breakthrough poisoning your reaction catalyst. Are you only working with partners that have desulfurization in place already? And how much attention do these skids need day to day, are you expecting full-time operator presence? Remote monitoring? How are you catching breakthrough before it takes out a catalyst charge?
I'm guessing bi-reforming is partly how you tune your way out of the carbon deposition problem, but in my experience real biogas composition drifts around depending on what's going into the digester, so i'm curious how much margin you actually have on the H2O/CO2/CH4 ratio before you're back in the coking regime. Are you trimming steam in real-time based on gas composition or running fixed excess (further trading economics)? Was the bench-scale test run on a simulated dynamic biogas stream? Was there much activity decline over the run?
On the economics side: DME into cosmetics seems like a great high-margin entry point. As you point out, most methanol is produced from large centralized plants, but they have real fixed-cost advantage that a modular approach structurally doesn't (along with storage and distribution headaches from many smaller production sites). Are you assuming some customers will pay a premium for the resilience of a distributed network? How much of the methanol case is cost reduction at your expected scale versus 45Z-type credits? And you probably can't share, but I'm curious the most you can pay a producer for their biogas and still pencil relative to RNG buyers who may be bidding for the same stream?
jonavanoord
an hour ago
Thank you so much for the thoughtful comment and questions :)
We take in raw biogas and do the scrubbing ourselves. We are working with a specialized gas cleaning firm to build the gas cleaning step of our process. It is not as OPEX heavy as you would expect and we have a very good sense of how clean we will be able to get the gas with this system (down to low ppb levels). We monitor H2S levels continuously and that informs us whether there is a risk of poisoning the catalyst. At scale the whole unit will be automated, including this step of the process and will only require attention for maintenance and restarting after a shutdown.
I cannot comment to much on how we attack this problem. What I can say is that we do have a solution for the biogas composition drifting. The bench-scale test was partially run on a dynamic biogas stream as we did tune it once or twice over the 1800 hours, but not heavily. There was no real activity decline over the 1800 hour run, we stopped it because our methane cylinder ran empty funnily enough.
You make a great point on competing versus large scale plants with the economies of scale advantage. One way we look to attack that advantage is by numbering up, going down the manufacturing learning curve and seriously reducing our CAPEX from FOAK to NOAK. Another way is simply by being able to deploy these units super fast and have them paid back by the time a large plant would be in the permitting phase.
From an OPEX perspective, we have found that Urban Areas as well as some rural areas present really great opportunities for localized distribution networks where a chemical customer is always surrounded by a multitude of biogas sites. This enables us to cut transport down to a fractional cost because we are moving DME only 50 miles instead of 500.
Lastly, we do not bake in any credits into our cost models. Even so, our TEA and ASPEN simulations show we have some of the lowest cost green DME and Methanol outside of China. Part of that is because we do get biogas for quite cheap, many of the sites we are targeting are too small for RNG. Even if they are large enough for RNG, many sites really like the 0 capex solution that we are commercializing. At the current price we are paying for biogas we are the most profitable biogas utilization solution for 80% of biogas volume (measured by how much net cash flow we generate for the biogas producer over a 20 year lifespan)
We really appreciate the questions! If you are interested in asking more questions feel free to reach out via linkedIn or at jona@rise-reforming.com!