Remember on my last post where I mentioned that my job can be very easy, as long as I don't have to go and get the sludge? There are jobss such as digester and lagoon cleanings where we have to go and get it. Then, my job morphs into ideal fodder for the TV show, "Dirty Jobs." Then, it turns into very hard, very dirty work.
FYI, I'll fill you in on what both of these are. Lagoons are nothing more than large, aerated ponds that treat sludge by growing bugs that break down all of the nutrients in the wastewater coming in. The solid waste simply settles to the bottom of the lagoon and forms a thick layer with the consistency of mud. Most lagoons are 15 feet deep but operate at a 10 foot water level. When the sludge reaches 4 feet in the lagoon, it has to be cleaned out. Lagoons are mostly used in very small towns because they take up a lot of space and don't provide nearly the same amount of treatment in the same area that a more modern treatment plant can. Plus, they're very low maintenance. They may only need to be cleaned out once every 10 years.
Digesters are a tank used in modern treatment plants. They are covered and sludge is fed into them where it's heated, causing a release of methane. You can easily spot these at a modern treatment plant. Usually, the excess methane is burned off so you'll see an open flame. Lately, treatment plants are setting up generators that can turn that methane into electricity. In any case, they accumulate sludge just like a lagoon does over time and they have to be cleaned out or they start losing digestion. Like a lagoon, the sludge becomes mud-like and won't flow.
As much as I can love an inatimate object, I love this pump. It's centrifugal, hydraulic-driven submersible pump. It can easily pump sludge as thick as mud at rates over 300 Gallons Per Minute and push it for hundreds of feet. I've even pumped such material 35 feet, straight up! It can also pass a piece of solid up to 4" in diameter. While it's a great set-up, it also weights around 170 lbs. Those hoses easily weigh 80 lbs each. So, set-up and moving this wonderful piece of machinery is also ass-busting, but, oh so worth it!
This is the inside of the digester I'm currently cleaning. Soon enough, we'll have to get into this wonderful puddle of mud with a water hose and thin it out with a fire hose since it'll be so thick it won't want to flow. It's always fun trying to tread through 2' of this stuff while dragging 50 or so feet of water hose with you. At least in a digester, it's cooler. We have to do the same thing in a lagoon too, but this time we're out in the weather (usually, we do this work from July to September). Bear in mind, we're also wearing rubber chest waders while doing this. That gets hot after a while.
Yeah, it's gross but to be honest with you, I really enjoy this job. It pays really well and the job security is great (are you going to stop flushing any time soon?). I get to travel a lot and see some great stuff. We're on the cutting edge in our field and that's a fun place to be, as far as I'm concerned. Most of all, I get to do a good-paying job that requires some elbow grease. Ocasionally, I have to do some office work but, at heart, I'm the kind of guy who likes to move. Sitting down for too long drives me crazy. Plus, I never got over the childhood joy of getting dirty.