Did you ever think, that you’ve taken the wrong career path?
I don’t mean wishing you’d become a porn star or a millionaire novelist. I mean something normal. An actual normal job which earns no more or less than your current occupation, just different.
I’ve had thoughts about changing career in the past, just like most people do. Not doing my hobby for a job thoughts, I’ve done all that and realised much as it’d be great and everything, it wouldn’t be great. Doing something you do for fun, I think, could make you hate it. No, that’s not true. I got into IT because I liked messing with computers, and now I’m paid a lot of money to tell other people what to do with IT. I don’t hate it. It’s a little soulless at times but meh. Pays for bike bits and booze.
Anyway, my head has been turned. You see, I work in the water industry.
Water production is incredibly important. Honestly, if it fucks up, you’re about 12 hours from mayhem and death. It’s not very exciting though. Here’s how you make drinking water.
Collect some water, clean it up a bit, disinfect it a bit, give it to people to drink. Yawn. The scale is quite interesting and the delivery logistics are certainly challenging but that’s about it. I bet you didn’t know that we create a head, or service reservoir to maintain supply rather than producing on demand. Huge, great ,massive, swimming pool sized cisterns. Obvious really, actually you probably did know that. See? Yawn.
Now shit is interesting. We all do it, but once you flush that chain you forget about it. But that’s where it gets really interesting. The things with humans is, we shit a lot, and someone has to take it all, get that nasties out, get the goods out, maybe make a bit of money out of it, return some of it to nature. Now *that’s* interesting.
Let me take you through the modern day sewage treatment process.
Once the raw sewage arrives at the treatment works, all the big bits need taking out. Toothbrushes, nappies that have made it this far, dead dogs. So it passes through a big grate and all the big bits fall into a skip. Those skips. N I C E. Interesting point. Apparently tomato seeds pass through the human body undigested, so lots of them fall into the skips that are full of nutritious material. Beautiful tomatoes at a sewage works.
Onwards for the sewage though. First off, we need to let it settle. Pump it into primary treatment. Big vat of water. Oily, frothy bits come to the top, hard, heavy bits fall to the bottom. All the bits that float to the top get pushed into a holding tank, sometimes this stuff is used to make…errrmm, brace yourselves…soap. Not really in the UK though.
Anyway, so now we have a load of fairly nasty water filled with properly dangerous microbes, and a load of sludge. This shit (I’m here all week), suddenly got interesting.
The microbe water goes off to be de-dangered using an aerobic biological process. Here a live culture of good bacteria (for want of a better phrase), process the water and remove most of the deadly bacteria by feeding on it. The culture must be kept alive and healthy, warm and fed with oxygen. Heat helps, I wonder where we can find some of that? Read on to find out. The clean water is dumped back into a local water source. Really, it’s good now. In storm conditions, large holding tanks capture the excess of wastewater but sadly, sometimes there’s too much and it, ahem, is just released. Sorry about that.
The sludge? Aah, here’s where things get awesome. You see, there’s an old Northern expression. ‘Where there’s muck, there’s brass’, and sludge is very much, muck. Sludge is, one the whole, quite wet. And it’s not a huge amount of good to any one in that state. In the UK we used to spread it around the place to leave it to dry out. Slow though. The best thing to do with sludge is harvest its methane. Sludge gives off methane quite a lot. Especially when it’s nice and warm and wet.
So we’ve got some wet sludge. Pump it into a big tank, add plenty of heat. The bacteria in the sludge gets very excited and starts making methane as it’s post-excitement exhaust gas. It’s not very pure though so we push the gas through some scrubbing systems to make it nice and clean. Now we have pure methane. What are we going to do with that?
Put it in some big holding containers, that’s what. Inside the balls are big bags that fill up with methane.
What are we going to do with the methane? Chuck it into one of these of course.
Combined Heat and Power (CHP) units turn biogas into electricity This is quite a big one. Believe me, once they’re up and running it’s quite impressive. These things generate megawatts of electricity which can be used to run onsite equipment (you probably didn’t know that the water/wastewater industry is one of the largest users of electricity in any country), or pumped back into the grid.
CHP’s generate a lot of heat so that can be pumped back into the start of cycle to get the sludge excited. It’s almost poetry isn’t it? We still haven’t finished with the sludge though. Once all it’s excitement is over it is dried out and turned into fertiliser.
Now you tell me all that isn’t more interesting than computers. I bet you didn’t realise your poo did all that after you’d flushed the chain, did you? And if you had a choice to work with computers or poo, I know which option you’d take.