Water and Sewage Treatment: Expertise Unlimited

A call-out to a groundwater treatment plant earlier in the week showed a few interesting problems. "Dirty" power from a failing generator caused the failure of a single instrument (a Siemens Hydroranger), but the knock-on effect was total plant failure.

The software programmer had "interpreted" the requirements of the Functional Design Specification in such a way that this instrument became critical for plant operation. This was especially annoying as there was a backup instrument working on a more robust principle, but no way to switch plant operation over to this alternative instrument without a programmer on site.

Of course at the point where I was called, the working day was coming to an end, the plant's feed lagoon was on the point of overtopping, and it was raining. I love a challenge!

Naturally there was an expedient way to get the plant to go again, but the fix was a little questionable. I consequently thought it best to connect a web-cam into the system so that I could see and hear what was going on remotely, as well as being able to see what the SCADA shows. All is now well with the plant.

Labels: emergency callout, groundwater, treatment, troubleshooting

I've been quite busy with learning to teach, but I went down to see a plant I upgraded about a year ago last Friday for a "health check".

As it took the operators three-quarters of an hour to even find the O+M manual, it looked as if it hadn't seen much use. The recommended daily checks had been reduced to a quick look through the fence as they went past, and no checks at all on weekends or holidays. They had turned the coagulant dose right down and filled the plant with 32% acid and alkali to save on chemical costs, and unsupervised tanker drivers had been walking on the tray-work. Despite all of this, everything was still basically working.

I'm going to do a bit of lab-work this afternoon to see if they can use a cheaper coagulant than the fancy blend the original plant installers recommended. At £2 a litre, I can see how they want to turn the dose down, even if it does degrade plant performance.

I'm off to Nottingham this morning to see a few examples of good lecturing practice, and if I have time, I'm going to make a start on the anaerobic digestion course I'm doing for Loughborough.

Labels: effluent, industrial, plant, treatment, troubleshooting

This is the polymer dosing pump and storage tank, for dosing an aluminium based coagulant for colour removal.

We refitted the old polymer dosing pump to a reconditioned IBC, and new downpipe. We also replaced its outgoing line with new twinwall stock.

The polymer pump was rewired to the new control system and interlocked to feed pump operation from its inverter.

Labels: alum, chemical, design, dosing, effluent, engineer, environment, etp, industrial, pharmaceutical, plant, problem, pump, treatment, troubleshooting, wastewater, water

Spent a long day yesterday troubleshooting problems with the duff effluent treatment plant for the pharma client previously discussed. Managed to solve his excessive flow to sewer by simply restricting air flow to his diaphragm pumps. The client had not thought of this because he was convinced that his effluent flow rate was around five times its actual value. Always good to check your assumptions. Couldn't get his pH correction system online, due to problems with an injection lance, but increasing the alum dose brought the pH into spec. anyway. Just the problems with COD, suspended solids and heavy metals to solve now.

Also had a call from the Environment Agency yesterday about a former client who has tried to solve his own problems with an undersized effluent treatment plant. Like a lot of inexpert clients with such problems, he had been duped by a succession of snake-oil salesmen into trying all sorts of quick fixes, none of which had worked. He only carried out the cheaper of my recommendations, as cheaply as possible, and now it seems he is likely to get prosecuted.

The morals are:

1. All the magic bugs, fat dissolvers, swimming-pool filters and chemical dosing in the world will not save you if your plant is not the right size, installed, operated and maintained correctly. If it is correctly designed, installed, operated and maintained, you will not need these things.

2. If you spend money on a consultant, follow his suggestions. Waving a report whose suggestions you did not implement at the EA will not save you from prosecution.

Experiments on PCB containing oily sludges are going OK, in the strict scientific sense. That is, we have no growth yet of either anaerobic or aerobic organisms on the stuff. Of course, from a practical point of view, this disappoints.

Labels: agency, alum, COD, dosing, environment, pH, pharmaceutical, plant, problem, sewage, solids, suspended, treatment, troubleshooting, water

I've decided to start a blog on the company website, covering things which interest me professionally.

I'm a Chemical Engineer and Environmental Scientist, working mainly in the field of Water Engineering, though I do also deal in more general environmental advice, mostly on behalf of a government funded scheme called Envirowise.

I used to work for water contractors who you will not now have heard of, because it is seemingly a rule in the water industry that companies have to change the name of their company from time to time, for a number of reasons. For good companies, this is usually something to do with the marketing department. For bad companies, the reasons may be less honourable. None of the people I used to work for went bust by bidding jobs at less than cost and then came back one month later as "(old company name) 2008 Limited", but this is far from uncommon in the industry.

I do quite a bit of work of packaged sewage treatment plants which are misbehaving, look after some groundwater treatment plants, and am also presently involved in something I do a bit of from time to time, water feature design. I am helping with the design of water features in the Parc1 development in Korea. Don't click on the link unless you have broadband, the graphic designers have gone nuts on the website.

I'm also interested in water quackery, and will post some stuff on this as I come across new examples.

Labels: chemical, design, effluent, engineer, environment, etp, groundwater, industrial, package, PCB, pharmaceutical, plant, problem, sewage, sludge, treatment, troubleshooting, wastewater