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The first thing which came to my mind was the argument against nuclear energy; it produces too much waste. The waste from yogurt seems to be a far bigger proble

The first thing which came to my mind was the argument against nuclear energy; it produces too much waste. The waste from yogurt seems to be a far bigger problem though. While not so long-term, it is massive. Interesting to draw parallels. Over here there's a syrupy-like product called Calpis. It's slightly acidic yet milky and sweet. As far as I remember, it is made at least partly from this byproduct. Of course it's a small step to the solution. Another ten cents, if it is largely water based, what about letting the water evaporate? Or does the acid go with it? I apologize for the unrelated thoughts.

icegreentea 13y ago
The problems with waste are clearly a short-term issue caused by unexpected growth. If they can absorb ~70% of their acid whey by product by mixing into nearby farms, then given the sheer amount of livestock in the US, you can definately absorb all of it if you solve the distribution/logistics problems. Really, all of the solutions the come up with will work. None of really have a real scaling issue, but they do require capital and have lag-time, which apparently were not sufficiently considered. The problem here isn't that 'oh, there's a river of this "toxic" waste that we don't know what to deal with'. The problem is 'oh, we've tripled our production without having a solid plan on waste disposal, and we don't want to pay more to truck this stuff to further farms'.
mrb 13y ago
I was thinking of letting it evaporate too. It seems this is the less costly option. No need to truck it anywhere, just dump it in big artificial pools. Once in a while, collect the solid waste from the pools (lactose, mineral, proteins). They say this waste is dangerous for the environment, but maybe not when it is in solid form?
- icegreentea 13y ago
  Here are the following problems. Firstly, the sheer scale. One of the major producers makes 150 million gallons a year. Or half a million gallon a day, or roughly an olympic sized swimming pool. Or... lets go all out. Half a million gallons is roughly 2 million liters, or 2 million kilograms of water. Assume air temperature of 20 degrees. To boil off the water, its going to take 4 kilojoules per kilogram per degree celcius.... so thats 640 GJ already. Ignore heat of vaporization. Incident solar radiation at like ... 1000W per m^2. 12 hours -> 43200 seconds per day, so 1 m^2 receives 44MJ is a day... which means you need about 15000m^2 of surface area to evaporate off a day's worth of production in a day. Optimistically.
  - rdl 13y ago
    Which really doesn't seem like that big a deal for a farm or large factory -- it's a 100m x 150m pad. Presumably you could keep it sanitary by using plastic sheeting over a concrete pad.
  - takluyver 13y ago
    Actually, I think the heat of vaporisation is more than the energy to heat the water to boiling: 2.26 MJ/kg, which takes us to ~4TJ/day. The 1000W solar radiation is also for the sun directly overhead without clouds, which obviously can't happen for 12 hours a day. I've found a source saying Bangkok gets something like 20MJ/m^2/day, and higher latitudes presumably have less. With those figures we're at 200000m^2 of evaporation area, and it's still optimistic (what about rain?).
  - nijk 13y ago
    That is a completely reasonable size for an industrial pond.
  - ars 13y ago
    It's not necessary to heat water in order to evaporate it. The energy calculations are completely off. The main thing you need is low humidity, and/or lots of wind.
ars 13y ago
> .. the argument against nuclear energy; it produces too much waste. ??? Nuclear power produces less waste than any other energy source on earth - including solar and wind. And coal produces more nuclear waste (by volume, not intensity) than nuclear power does.
- r00fus 13y ago
  Nuclear power generates a large amount of waste heat - which, in turn, acidifies local waterways. Nuclear power, even with subsidies, to be profitable/feasible, requires a very large amount of fresh water (or de-salinated sea water). It's actually a bigger problem than whey - there's no market to absorbe the waste output.
  - ars 13y ago
    > large amount of waste heat - which, in turn, acidifies local waterways Say what??? That makes no sense. Do you really believe that, or did you typo? Yes, nuclear power does need a heat dump, but the waste heat has only a local effect on the water in the close vicinity. You understand that it doesn't really consume the water right (except for a small amount that evaporates)? It just dumps heat in it, then sends it downstream, which isn't great for fish, but it's not terrible either - the effects are minimal, and local only, by the time the water flows a bit downstream it has cooled off back to the normal temperature. And you can use sea water, the salt doesn't effect the cooling ability, but I don't think there are any plants near coastlines.
ars 13y ago
> Another ten cents, if it is largely water based, what about letting the water evaporate? They could run it through reverse osmosis, which is already commonly done in industrial scale. This would not get rid of the all the water, but just take it down 90% would be enough.

icegreentea 13y ago

The problems with waste are clearly a short-term issue caused by unexpected growth. If they can absorb ~70% of their acid whey by product by mixing into nearby farms, then given the sheer amount of livestock in the US, you can definately absorb all of it if you solve the distribution/logistics problems. Really, all of the solutions the come up with will work. None of really have a real scaling issue, but they do require capital and have lag-time, which apparently were not sufficiently considered. The problem here isn't that 'oh, there's a river of this "toxic" waste that we don't know what to deal with'. The problem is 'oh, we've tripled our production without having a solid plan on waste disposal, and we don't want to pay more to truck this stuff to further farms'.

mrb 13y ago

I was thinking of letting it evaporate too. It seems this is the less costly option. No need to truck it anywhere, just dump it in big artificial pools. Once in a while, collect the solid waste from the pools (lactose, mineral, proteins). They say this waste is dangerous for the environment, but maybe not when it is in solid form?

icegreentea 13y ago
Here are the following problems. Firstly, the sheer scale. One of the major producers makes 150 million gallons a year. Or half a million gallon a day, or roughly an olympic sized swimming pool. Or... lets go all out. Half a million gallons is roughly 2 million liters, or 2 million kilograms of water. Assume air temperature of 20 degrees. To boil off the water, its going to take 4 kilojoules per kilogram per degree celcius.... so thats 640 GJ already. Ignore heat of vaporization. Incident solar radiation at like ... 1000W per m^2. 12 hours -> 43200 seconds per day, so 1 m^2 receives 44MJ is a day... which means you need about 15000m^2 of surface area to evaporate off a day's worth of production in a day. Optimistically.
- rdl 13y ago
  Which really doesn't seem like that big a deal for a farm or large factory -- it's a 100m x 150m pad. Presumably you could keep it sanitary by using plastic sheeting over a concrete pad.
- takluyver 13y ago
  Actually, I think the heat of vaporisation is more than the energy to heat the water to boiling: 2.26 MJ/kg, which takes us to ~4TJ/day. The 1000W solar radiation is also for the sun directly overhead without clouds, which obviously can't happen for 12 hours a day. I've found a source saying Bangkok gets something like 20MJ/m^2/day, and higher latitudes presumably have less. With those figures we're at 200000m^2 of evaporation area, and it's still optimistic (what about rain?).
- nijk 13y ago
  That is a completely reasonable size for an industrial pond.
- ars 13y ago
  It's not necessary to heat water in order to evaporate it. The energy calculations are completely off. The main thing you need is low humidity, and/or lots of wind.

ars 13y ago

> .. the argument against nuclear energy; it produces too much waste. ??? Nuclear power produces less waste than any other energy source on earth - including solar and wind. And coal produces more nuclear waste (by volume, not intensity) than nuclear power does.

r00fus 13y ago
Nuclear power generates a large amount of waste heat - which, in turn, acidifies local waterways. Nuclear power, even with subsidies, to be profitable/feasible, requires a very large amount of fresh water (or de-salinated sea water). It's actually a bigger problem than whey - there's no market to absorbe the waste output.
- ars 13y ago
  > large amount of waste heat - which, in turn, acidifies local waterways Say what??? That makes no sense. Do you really believe that, or did you typo? Yes, nuclear power does need a heat dump, but the waste heat has only a local effect on the water in the close vicinity. You understand that it doesn't really consume the water right (except for a small amount that evaporates)? It just dumps heat in it, then sends it downstream, which isn't great for fish, but it's not terrible either - the effects are minimal, and local only, by the time the water flows a bit downstream it has cooled off back to the normal temperature. And you can use sea water, the salt doesn't effect the cooling ability, but I don't think there are any plants near coastlines.

ars 13y ago

> Another ten cents, if it is largely water based, what about letting the water evaporate? They could run it through reverse osmosis, which is already commonly done in industrial scale. This would not get rid of the all the water, but just take it down 90% would be enough.