2. The drying process is not needed as biofuel can be made with wet chemistry processes.
3. The grey water treatment is a very good idea. The value added would be larger than the value of the biofuel. I have done experiments in this area with an Environment Canada grant on municipal wastewater and am part of an ongoing collaboration to develop the idea further. One of my scientific collaborators is a greenhouse expert. I suggest you read his publications.
http://www.greenhousecanada.com/content/...
4. There are higher value uses for the algae than fuel.
5. Tall buildings don't receive any more incoming radiation than the flat field shaded by the building. The direction of illumination changes with time of day and season. How about putting up buildings with concave shapes to act as giant focussing mirrors? This would improve the efficiency of your system.
6. Other plants are easier to harvest. I have done experiments with Lemna (duckweed). The doubling time is 27 hours and it can be used as a substitute for corn mash in ethanol production. You would need to make the water slightly acidic pH~6 for optimal production.
7. The temperature of the water tank needs to be regulated.
8. Your scheme would be more economic growing tomatoes and green peppers, etc. instead. You would need to do an assessment of contaminants in the grey water.
I have seen some good presentations on something like you are talking about. Development of industrial scale bio-diesel production from algae. It can work, but at this time it is NOT economical. Also, the structure you are talking about would NOT be efficient.
Current produciton model is kinda like described below.
Large Warehouse with high ceilings.
Roof is a solar roof i.e. mostly windows.
Racking system installed so you can hang your production equipment
Production in this case are bags (clear) of water and algea. Each hanging rod or stick would be 10 - 20 feet tall. (There is no specific reason you could not make them taller, just engineer for it)
Racking system constantly moves so each bag in each stick gets equal amounts of light.
Have a lighting system in place (grow lights) for days with little natural sunshine and/or to increase total exposure time to light to maximize growth.
After x period of growth, dependant of the specific algae being used, the bags of algae and water a borght to the production center where you derive your bio-fuel from algae.
This owuld be a constant and continuous production line. As a stick or rod is taken of the rack for produciton a new stick or rod is added to the starting point. All stick and/or rods are kept in near constant motion moving in a serpantine pattern to maximize exposure to light. Length of the line depends on your programmed speed of the line and required growth time for your algae.
I hope this helps. It should also help you to uderstand the flaws or limitations with the design you suggested.
Interesting idea, although, even though photosynthesis stops when the Sun stops shining, as a general rule, photosynthetic organisms require oxygen when photosyntheis stops. In order not to require oxygen, you would need a strain of algae which would either become dormant or could withstand lactic acidosis. However, besides eliminating the requirement for oxygen, such strains of algae would avoid conversion of some of the biomass back to carbon dioxide.
It is creative anyway. I disagree with the statement that a tall building doesn't get any more sun. I think it does except at Noon.
Might have value as a way to conserve water and grow fuel for certain appropriately situated buildings. As a means of sequestering CO2, it would have roughly the equivalent impact of stopping incoming ocean tides by building a sand castle.
The fatal flaw is what exactly do you expect to achieve by this feat ?
If your aim is to try and use this machine to control the weather and make a colder Earth, well good luck with that one x.
I see a problem with the solar part, I mean the pump/compressor need to run 24hrs a day, so that means batteries and they would be a weak link in your system.
Sorry chem, you are on the wrong horse. CO2 is now a dead duck as it goes higher whilst the global warming gets less thus blowing the connection there. With the shale gas going ahead, the need for expensive bio fuel will disappear. We are not in a post apocalypse situation yet and will not be for hundreds of years, if ever.
The real flaw is that the Earth's temperature has cooled for the last decade plus. While at this same time the CO2 level has increased. There is no correlation between temperature and CO2 level. You would uselessly go to all that effort and have no positive results.
Any real scientist would understand this.
global warming is a hoax
Cities have higher ambient CO2 than other areas. They also have lots of tall buildings. I'm thinking of some sort of automated algae-collecting system that could either generate biofuel, or simply sequester carbon, with fairly minimal expense and effort.
The system would be about like this. You have a tank on the sunny side of a tall building. It's clear, to let in light, and has a solar-powered pump to pump in air (in fact, all the mechanisms are powered by solar panels). It also has a mechanism that will periodically drop some of the water a few feet down a shaft to a filter. After the water goes through the filter (to collect some of the algae), it is pumped back to the top, adding a bit more if water levels are low. Building greywater and the like could be used, rather than using fresh tap water. Periodically, an automatic scraper will clean off the filter, and collect the resulting algae in something like a tiny trash compacter. Once the compactor is full, it squeezes out the excess water (as much as it reasonably can), then drops the brick of compressed algae into a hopper to dry the rest of the way. The hoppers are emptied periodically (likely once every few months), and the contents are processed (as much as practical) to remove phosphorus and the like (which get added back into algae systems, or used as fertilizer), then the remainder is either burned for energy or buried.
Any fatal flaws you see with the idea? Do you think it would be practical with present technology? Any other thoughts?
