Ask me anything about wastewater and sewage

[Guybrush]

Okay, so of all my thread ideas, I suspect this won't be the most attention grabbing, but what the heck ask me anything about wastewater and sewage (& related). Maybe you're curious about treatment or sludge or whatever.

To answer questions, I will call upon my experience working with wastewater management and from my time working as a pollution case worker working with industrial wastewater. Possibly, I may also have to conjure up something from my ever more distant background in biology.

Shoot! 💩

[Janszoon]

Believe it or not my sibling has had a very similar career to you!

[Guybrush]

Believe it or not my sibling has had a very similar career to you!

Wow, that's weird. I hope he encounters as many poop jokes on a daily basis as I do 

What does he do in wastewater?

[Janszoon]

I hope he encounters as many poop jokes on a daily basis as I do

He did when he worked at a sewage treatment plant.

What does he do in wastewater?

He's a marine scientist, or whatever the term would be that covers fresh water too. These day he's involved with a lot of testing and cleanup of polluted waterways.

[Guybrush]

I hope he encounters as many poop jokes on a daily basis as I do

He did when he worked at a sewage treatment plant.

What does he do in wastewater?

He's a marine scientist, or whatever the term would be that covers fresh water too. These day he's involved with a lot of testing and cleanup of polluted waterways.

Probably marine biologist and limnologist combined.. or something.

Honestly, it roughly sounds like the sort of thing I'd like to be doing. I hope I can have a similar career arc 

[Janszoon]

I'm sure you will! You've always seemed like an intelligent and competent person to me, I'm sure you're very good at what you do.

[tristan_geoff]

Where does the poop go

[Janszoon]

Where does the poop go

Jack in the Box.

[tristan_geoff]

Where does the poop go

Jack in the Box.

Woah :0

[Guybrush]

I'm sure you will! You've always seemed like an intelligent and competent person to me, I'm sure you're very good at what you do.

Thanks Jans

Where does the poop go

If you flush it down a toilet, it hopefully goes into a network of sewage pipes and pumping stations that bring it to a wastewater treatment facility.

At the facility, your poop has been mixed into large amounts of water and is probably just a greyish thin soup. The trick is turning it back into a poop.

A series of processes take out t-shirts and action toys, rocks, sand and fats, perhaps also finer particles. Then you may have processes where bacteria are allowed to feed on the sewage to remove organic content or nitrogen and then there may be a big sedimentation pool that the water travels through slowly which allows particles to settle.  To make them clump together and sink faster, chemicals are often used at this stage; iron or aluminum here, typically, mixed with an acid. Sometimes a polymer is also used. At the end of the sedimentation pool, you skim clean water off the top as hopefully the particles that were in the water are either already taken out or have settled on the bottom. The clean(ish) water is sent out into nature, like a lake, river or ocean.

(Side note: some facilities do flotation instead of sedimentation where they blow bubbles into a smaller volume to make the sludge catch air and rise to the top where it is skimmed off).

The particular matter / gunk from these pools we call sludge. It gets sucked out from the bottom and sometimes sent into big tanks with bacteria to turn part of the the carbon and hydrogen content into methane. It also typically goes through processes that takes a lot of the water out (like centrifuges or sludge presses) so that after treatment, you're at a water content of 75% or (preferably) less where it's kinda gone back to being a poo. You can compost that and turn it into dirt you can put in a landfill or somewhere else.

If you get a lot of water out, say perhaps more than 60%, you can burn it in an oven to run a steam turbine. You then get ashes high in metals (hazardous) that you typically have to lock away someplace. On the upside, you get a lot of energy you can use and the volume of ashes will be small compared to the much larger amounts of sludge you'd have to manage otherwise.

Some facilities have other cool processes like pressure boiling sludge at very high temperatures, but this is the jist of it, at least here.

IF you pooped on a rainy day, that poop may not get to the treatment facility as it may get flushed out to the nearest river or seaside, typically from a pumping station, if the rainwater steals all capacity and the pipes are full. This is something we're constantly working to avoid / reduce.

TLDR; it depends, but your poop probably ends up as dirt somewhere after being separated from the water as sludge at a wastewater treatment facility.

[Psy-Fi]

If you flush it down a toilet, it hopefully goes into a network of sewage pipes and pumping stations that bring it to a wastewater treatment facility.

At the facility, your poop has been mixed into large amounts of water and is probably just a greyish thin soup. The trick is turning it back into a poop.

A series of processes take out t-shirts and action toys, rocks, sand and fats, perhaps also finer particles.

[Toy Revolver]

what's the most destructive substance that is likely to end up in the sewage

[Guybrush]

what's the most destructive substance that is likely to end up in the sewage

Something we're struggling with now in a certain area is concrete. Lots of it which has basically fucked up the surface / storm water system in a certain area. It's runoff from a concrete factory in the area. I don't even know how you get hardened concrete out of a pipe or even if you can.

We also had our entire gas facility shut down for at least two weeks last year. We believe a truck with oil sludge (from oil separation units at gas stations and car washes etc) got dumped here. It's hazardous waste and should not go here. It killed off our entire methane producing bacteria culture and we eventually had to get a starter from another facility.

Last year, we got sludge from a local ice cream factory. It was full of these wodden sticks / handles that jammed up all our pumps. Also we had an employee who got poked by a discarded syringe, although I believe that generally sounds worse than it actually is and he was fine.

You could theoretically get something like ebola disease poop coming down, but they got special wastewater protocols for the hospital quarantine wards in those instances.

Someone always knows someone who's seen an explosion in the sewer system due to people dumping gas / oil / paint / hydrocarbons of some kind. You hear stories about lids going flying many meters up in the air. They're really heavy.

For us, if you're asking what's gonna hurt us in an economic sense, then whatever kills our methane bacteria is the most likely hurt. Each day that gas facility is out of operation, we have to buy more electricity, transport way more sludge and have to buy diesel to warm our facility, so those costs rack up fast.

Heavy metals is an occasional annoyance as it fucks with how our sludge can be treated. If it contains too much of a metal, it becomes hazardous waste.

Edit:

Oh and storm drains sometimes get fucked up by trees or large branches jamming stuff up, but an umbrella or a bike could do similar damage. Whole areas with many houses can quickly become flooded that way.

[Janszoon]

Reading all that made me think of that horrific fatberg they found in London a few years ago.

[Toy Revolver]

Heavy metals is an occasional annoyance as it fucks with how our sludge can be treated. If it contains too much of a metal, it becomes hazardous waste.

Do they change thechemical compound from H2O to something else?