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Flocculant/Disinfectant Powder

cdc.gov

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Re: Flocculant/Disinfectant Powder

#91

Post by FredPret »

tonyarkles wrote: post #68
FredPret wrote: post #65

Earlier quoted context omitted.

Do you happen to know what percentage of trees are from CO2 and what from the soil? I’ve always wondered how much carbon is captured in, say, a book, or a dresser

I don’t know the exact number, but came across a wild thought experiment a while ago that drove it home. Look at a big tree. There’s 3 things that could have gone into making it: water, air, and earth. If you look at the ground around it, there’s no hole where the tree grew. Sure, there’s the root system, but there’s nowhere near enough dirt missing to have made both the root system and the 50’ above-ground portion o…

That’s a good one. Though it’s possible the soil is less dense around the roots due to mineral absorption.

But I suppose the majority of the mass must come from water and carbon in the air.

Re: Flocculant/Disinfectant Powder

#92

Post by JaimeThompson »

FredPret wrote: post #56
avidphantasm wrote: post #44

This is great, but what happens to the sachets? Are the biodegradable? When I was in India a few years ago I was struck by all the newly introduced non biodegradable packing strewn about EVERYWHERE. The old unfired clay cups used by road-side tea vendors were great, but they were rapidly being replaced by little white plastic cups. Plastic is a scourge on the land and water resources.

I wonder how long it'll take for a plastic-eating microorganism to evolve. Apparently trees evolved hundreds of millions of years before the bacteria that can make wood rot arrived, so you probably had piles of dead trees everywhere for such a long time.

Paenarthrobacter ureafaciens KI72 also know as Nylon eating bacteria can eat Nylon. I am not a biologist so I know little more about it than what I read in [1].

[1] https://en.wikipedia.org/wiki/Nylon-eating_bacteria

Re: Flocculant/Disinfectant Powder

#93

Post by FredPret »

JaimeThompson wrote: post #92
FredPret wrote: post #56

Earlier quoted context omitted.

I wonder how long it'll take for a plastic-eating microorganism to evolve. Apparently trees evolved hundreds of millions of years before the bacteria that can make wood rot arrived, so you probably had piles of dead trees everywhere for such a long time.

Paenarthrobacter ureafaciens KI72 also know as Nylon eating bacteria can eat Nylon. I am not a biologist so I know little more about it than what I read in [1]. [1] https://en.wikipedia.org/wiki/Nylon-eating_bacteria

Nice! Nylon is from the 1920’s, so it only took 100 years

Re: Flocculant/Disinfectant Powder

#95

Post by engineer_22 »

Johnny555 wrote: post #85
engineer_22 wrote: post #76

Earlier quoted context omitted.

You could also ask your local water provider what their emergency plan is. Some parts of their emergency plan are confidential, but they are required by law to have a plan. The larger operators already have their Risk and Resiliency plans in effect, and smaller operators have a July deadline for their R&R plans. It's been my experience that water operators take a lot of pride in their work and are happy to educate th…

I'd rather prepare myself than rely on my provider's emergency plan. I can be sure if my house survives the disaster and I have my own purifier (whether this product or something else), then I'll be able to have drinking water. But even if my provider has a great plan, disaster plans aren't truly tested until the disaster strikes, so that plan may not be sufficient. I have both stored fresh water as well as a filter…

That's wise. Still curious what local utility says. Might be eye opening. I used to supervise a treatment plant, we were well prepared to deal with disasters.

FYI a flocculant can be used to settle out really dirty water, it needs to be mixed well to work correctly. Flocculants include ferric and alum. Bleach is typically used as a disinfectant to reduce bacteria and viruses. Oocysts are not destroyed by chlorine and have to be filtered out. Most surface water treatment plants use sand filters. Granulated carbon filters are increasingly common to remove trace chemical contaminants, but these will also adsorb chlorine, advise disinfectant after the filter step.

Re: Flocculant/Disinfectant Powder

#96

Post by Blahah »

Johnny555 wrote: post #86
Blahah wrote: post #66

Earlier quoted context omitted.

It's not going to be much use in distilled water, so it pretty much exclusively works in water with dissolved salts.

Are you saying it will turn saltwater into freshwater (it won't), or it will purify saltwater, but it will still be saltwater? I'm not sure which the OP was asking about.

I wasn't really saying either, but it certainly won't desalinate water. I was saying that almost all water this would be used on will contain dissolved salts, so that asking "what about water with dissolved salts" is moot.

Re: Flocculant/Disinfectant Powder

#97

Post by Pfhreak »

FredPret wrote: post #91
tonyarkles wrote: post #68

Earlier quoted context omitted.

I don’t know the exact number, but came across a wild thought experiment a while ago that drove it home. Look at a big tree. There’s 3 things that could have gone into making it: water, air, and earth. If you look at the ground around it, there’s no hole where the tree grew. Sure, there’s the root system, but there’s nowhere near enough dirt missing to have made both the root system and the 50’ above-ground portion o…

That’s a good one. Though it’s possible the soil is less dense around the roots due to mineral absorption. But I suppose the majority of the mass must come from water and carbon in the air.

Feynman on this exact question: https://m.youtube.com/watch?v=ifk6iuLQk28&feature=emb_title

Re: Flocculant/Disinfectant Powder

#98

Post by Pfhreak »

mahogany wrote: post #77
neurostimulant wrote: post #70

Earlier quoted context omitted.

Dry wood is about 50% carbon, 41% oxygen, 6% hydrogen, and 3% trace minerals, so it's probably safe to say that over 50% of it comes from CO2, and the rest from water and soil.

Is there not carbon in the soil? Edit: I misread what you said. I think you are claiming that because there is so much carbon and oxygen, probably more than half comes from CO2. But there is both carbon and oxygen (well really, air) in soil. Although apparently the concentration of CO2 in the soil's air is much higher than it is in the normal atmosphere, so it's possible your statement is correct. (Plus looking at dr…

Dry mass is typically used because it's consistent. Trees fluctuate over the year, being drier in some seasons than other. But they'll have the same dry mass.

Trees are mostly C6 H10 O5, coming from CO2 and H20. Based on atomic weight about 70% of the mass of the dry wood comes from CO2. Fresh wood will have extra water content, taken from the soil (though that water came from the air too).

There is carbon in the soil, but most plants don't take carbon up from their roots meaningfully. Nitrogen, phosphorus, potassium, and other trace minerals. Decomposers like fungi, bacteria, and insects will eat the carbon in the soil and release CO2.

Re: Flocculant/Disinfectant Powder

#99

Post by sitkack »

tonyarkles wrote: post #68
FredPret wrote: post #65

Earlier quoted context omitted.

Do you happen to know what percentage of trees are from CO2 and what from the soil? I’ve always wondered how much carbon is captured in, say, a book, or a dresser

I don’t know the exact number, but came across a wild thought experiment a while ago that drove it home. Look at a big tree. There’s 3 things that could have gone into making it: water, air, and earth. If you look at the ground around it, there’s no hole where the tree grew. Sure, there’s the root system, but there’s nowhere near enough dirt missing to have made both the root system and the 50’ above-ground portion o…

I have seen 50+ foot tall trees growing directly out of ancient lava flows, nearly zero soil.

From a cursory search, it looks like about 88% of the dry mass of a tree comes from the atmosphere (CO2 and H2O).

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