July 2007, Vol. 19, No.7

From the Editors

WE&T Prelude

Nuts and Bolt

Melissa Jackson

My father could build anything with his hands, be it a scale model railroad or fine furniture. From a young age, I watched him carefully transform hand-drawn plans into highly detailed, three-dimensional works of art. He could jump into these projects with confidence because he had an engineer’s mind. He knew how things worked (and didn’t work). As a boy he had taken apart countless old cars, tractors, and appliances to better understand the mechanics of the whole. By the time he was grown up, his reverse-engineering skills defined his worldview. As such, he did not have much patience for theory or how-to books: Much better to learn by doing.

I think that deep down, even those of us less mechanically inclined have a soft spot for hands-on approaches. Practical solutions are immensely satisfying to discover, and even more so to implement. (This truism even applies to “soft” technologies such as putting together this magazine!) This month we offer you some practical approaches to simplifying wastewater treatment — and the payoffs. From establishing an asset management program to minimizing sanitary sewer overflows, the scenarios featured in this issue are decidedly real-world and no-nonsense. We hope you find them interesting, and most importantly, useful.

— Melissa Jackson, editor
mjackson@wef.org

Melissa Jackson, editor

Operations Forum Editor's No

A Rocky Path

Steve Spicer

I like to run. I probably run about 6 or 7 miles (10 or 11 km) a week. It’s an easy and inexpensive pastime. The only necessity is a pair of shoes; however, I usually add sunblock and a music player. It feels great to get moving and let all of the stresses of life fade away.

But two things will totally ruin a run. The worst, and thankfully rather uncommon, is an angry dog. (I like to run, but not when being chased by snapping jaws.)

The second thing is a rock in your shoe. At first, you just ignore it. It’s just a little rock, right? To stop and remove it would ruin your stride, wreck your time, and make it harder to reach your mileage goal. You wiggle your foot as you lift it to move the rock near your toes where it won’t bother you so much. But as you trot along, weirdly shaking your leg with each step, it works it way back along your arch. And on the next step, the rock has magically transported itself under your heel, grown three times its previous size, and sprouted spikes.

The magical spiky rock has never made me fall, but it’s been close on several occasions. I find it ridiculous that something so small can so drastically affect my performance. Surely, there is an easy way to avoid all this hassle.

There is: Stop and take the stupid rock out! Yes, that has its own complications — everything does — but it’s easier than continuing to run in pain.

Debris and grit entering a wastewater treatment plant is similar to that rock in my shoe. It’s a constant hassle to keep it out, and if it’s ignored it will rattle around until it causes problems. The only way to avoid the problems is to keep things cleared out. For my shoe, that’s pretty simple, but for wastewater treatment plants it’s rather complex.

The Industry’s Finest looks at several treatment plants’ experiences with installing fine screens to prevent trash and debris exiting the plant in effluent or biosolids, saving money on screenings disposal costs, and protecting membranes.

The Nitty Gritty focuses on the small stuff. This article is the first of a four-part series on how grit behaves and how grit removal systems can be designed most effectively. This first article defines some concepts and examines how particles behave in collection systems and treatment plants.

When it comes to running, I know what works for me. When it comes to wastewater treatment, Operations Forum is lucky enough to have experienced and talented authors who know what works in the field, as well as creative and innovative readers willing to share their own solutions. I hope you enjoy reading about what these folks did and are inspired to send in stories of your own successes.

— Steve Spicer, editor
sspicer@wef.org
 

Steve Spicer, editor