The energy cost to biomass --> ethanol is not in the distillation, it's in the enzymatic digestion of the biomass into fermentable sugars. Current processes require large amounts of enzymes made in a separate process. According to a recent talk at the annual meeting of the American Chemical Society in Boston, the smart money is in pairing the enzymatic digestion with microorganisms that exoress the enzymes. This compresses two steps into one ("process intensification") and as a side benefit, the enzymes and microbes work better together than individually.
Being a bit of a nerd in the area of virus filtration, I thought I'd pipe up.
This is a very bold claim. Commercialvirusfilters that are in the ~20 nm pore size rating tend to have capacities measured in the hundreds of liters per square meter (1 m^2 = 10 ft^2)--even with very clean feed streams seen in the biotech industry--and cost anywhere from $3000 to $6000 for the same amount of area. They are also difficult to clean and difficult to protect with pre-filters because the crap that plugs them can be much smaller than the pore size of the filters (material can deposit on the inside of the pore walls).
Throughput can be improved by operating in a tangential flow mode (flow sweeping past the membrane surface to avoid junk build-up), but this isn't a straightforward way to operate a filter bottle.
I have significant doubts about these claims. The more so because this page is completely blank. They don't even give reduction values for the particles they claim to remove. 90% would be very poor performance...99.99% is wher eit ought to be. How do they validate the pore size of the membrane (integrity test)? Many questions, 0 answers.
Back when I did FIRST (formerly US FIRST) in high school, the team that MIT sponsored was consistently among the worst. There was a team in the next town over from me that was only sponsored by Key Bank that was always much better and with far less apparent technical expertise.
He gave a talk for my organization a couple of months ago on his thermochemical process that converts cellulosic waste to precursor chemicals for fuels and fine chemicals. You can read a litte more on it here or by googling his name and Biofine. He claims the energy inmput/output ratio is quite good--I recall in the 30-40 range--and there is a process-scale facility online in Italy with interest to build a couple in the US.
Bah. Maps24 gives bunk directions to me. Rather than putting me right on the highway from home to work, it recommends I take a traffic- and traffic light-burdened Main St. (Waltham) that is actually out of my way (go south to go north?) to get to the 128/95 loop around Boston. No other map provider I've tried (MapQuest, Google, Yahoo!) does *that* poorly.
Transportation routes for hazardous materials must avoid population centers whenever possible. Like... Um... A major highway? The proposed route passes through the heart of the most populated areas
What it means is that you can't take tanker trucks full of Hazardous materials (not just waste, but things like LNG and fuel oil) through major cities. For example, in Boston the signs on I-93 and Rte 3 north of the city warn that truckers with hazardous cargo may not use I-93 (ie, the Big Dig) to pass through Boston to another destination. Instead they are to use I-95/Rte 128, a highway that passes around Boston...through the most densely populated suburbs. The key difference is that large buildings are directly next to (and now will be on top of) I-93 through Boston while there is at least a decent marging along the I-95/Rte 128 right-of-way.
It sounds to me like this new suerhighway passes around the major cities, thus satisfying the need to keep hazardous materials out.
And to the poster who mentioned rail...I think the drawback to this is that rail lines tend to pass through cities as a rule. Perhaps this project will have rail routes that bypass the cities as well; I did not RTFA in too much detail.
What I found totally ironic and amusing was the level of detailed used in describing why they found shows offensive. For example, check out their campaign against airing Sex and the City on TBS. They could very easilty explain that the objectional material was "graphic descriptions of sex act in a phone conversation between two characters." Instead, to fully inform concerned Christian parents everywhere, they include a verbatim transcript of Miranda having phone sex with some guy:
"Miranda: "You were touching my breast."
George: "Yeah, yeah, I'm touching your breast and I'm thrusting hard into you."
Is it just me, or do you get the picture that this is a very represssed group? One could imagine some galant warrior for Jesus posting this to the PTC site to inform his fellow faithful of the sinfulness of mass media, all the while sporting a raging stiffie.
As a biopharm engineer, I don't trust anything more open than a 200-300 kDa filter (about 10-15 nm) to clear all viruses by size excplusion. [/shameless plug];-)
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The energy cost to biomass --> ethanol is not in the distillation, it's in the enzymatic digestion of the biomass into fermentable sugars. Current processes require large amounts of enzymes made in a separate process. According to a recent talk at the annual meeting of the American Chemical Society in Boston, the smart money is in pairing the enzymatic digestion with microorganisms that exoress the enzymes. This compresses two steps into one ("process intensification") and as a side benefit, the enzymes and microbes work better together than individually.
This is a very bold claim. Commercial virus filters that are in the ~20 nm pore size rating tend to have capacities measured in the hundreds of liters per square meter (1 m^2 = 10 ft^2)--even with very clean feed streams seen in the biotech industry--and cost anywhere from $3000 to $6000 for the same amount of area. They are also difficult to clean and difficult to protect with pre-filters because the crap that plugs them can be much smaller than the pore size of the filters (material can deposit on the inside of the pore walls).
Throughput can be improved by operating in a tangential flow mode (flow sweeping past the membrane surface to avoid junk build-up), but this isn't a straightforward way to operate a filter bottle.
I have significant doubts about these claims. The more so because this page is completely blank. They don't even give reduction values for the particles they claim to remove. 90% would be very poor performance...99.99% is wher eit ought to be. How do they validate the pore size of the membrane (integrity test)? Many questions, 0 answers.
Who now with the what now?
Back when I did FIRST (formerly US FIRST) in high school, the team that MIT sponsored was consistently among the worst. There was a team in the next town over from me that was only sponsored by Key Bank that was always much better and with far less apparent technical expertise.
He gave a talk for my organization a couple of months ago on his thermochemical process that converts cellulosic waste to precursor chemicals for fuels and fine chemicals. You can read a litte more on it here or by googling his name and Biofine. He claims the energy inmput/output ratio is quite good--I recall in the 30-40 range--and there is a process-scale facility online in Italy with interest to build a couple in the US.
Oh, and Maps24 got the address of my place of work wrong by TWO whole towns! (even though it located it on the map correctly)
Bah. Maps24 gives bunk directions to me. Rather than putting me right on the highway from home to work, it recommends I take a traffic- and traffic light-burdened Main St. (Waltham) that is actually out of my way (go south to go north?) to get to the 128/95 loop around Boston. No other map provider I've tried (MapQuest, Google, Yahoo!) does *that* poorly.
And this is not realted to another auction?
Perhaps if said parent R(ed)tFA, he would have noticed that the author was not a native English speaker....
But that's just me ;-)
As a biopharm engineer, I don't trust anything more open than a 200-300 kDa filter (about 10-15 nm) to clear all viruses by size excplusion. [/shameless plug] ;-)