Saturday, 13 December 2008

Clarifier Upgrade: Pharma ETP

Effluent Screen by Expertise Limited Water Engineering Experts 

We enhanced the performance of the final clarifier by fitting a stainless steel screen to the outlet.

As our screen was square, and the tank was not, this took a certain amount of effort, and plenty of mastic!

Fitting the screen in this way enhanced clarifier performance from peak concentrations of 5000 mg/l suspended solids to1/10th of that figure.

Controls: Pharma ETP

Originally uploaded by
Controls: Pharma ETP


The overly complex PLC based controls of the original plant were replaced by a dedicated pH controller, and these three boxes.

These are a distribution board, an ultrasonic controller, and an inverter.

These replace the plc without a human interface which the original installers used.

Since at least monthly intervention is required to calibrate the pH probe, this might be viewed as a design weakness, or an attempt to prevent the purchaser from using another plant maintenace company.

Polymer Dosing: Pharma Effluent

Polymer Dosing
Originally uploaded by
Polymer Dosing: Pharma Effluent

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.

pH Dosing Kit: Pharma Effluent


This is the pH correction system, dosing up to 32% HCl and 20% NaOH by means of dosing pumps controlled by the yellow unit in the foreground. Dosing Kit
Originally uploaded by

Chemical storage is 2 No. 1000 L reconditioned IBCs.

Dosing lines are twin-wall for safety.

Chemical dosing operation is interlocked to feed pump operation via a feed from the inverter.

Friday, 3 October 2008

Dihydrogen monoxide

For those of you unaware of the dangers, take a look at the MSDS for DHMO. Worrying stuff. Dangerous chemicals seem to be everywhere now.

Thursday, 18 September 2008


We have added some new content to the website, in the form of a collection of recent publications:
some book reviews, a water feature design manual, an article on packaged waste water treatment plant problems, and a literature review on PCB water treatment technologies.

Things are proceeding well in other areas, getting ready for the pharma. plant upgrade in November, and picking up a few new clients.

Wednesday, 3 September 2008

Pharma Plant etc...

Detailed design is proceeding with the pharma effluent treatment plant upgrade, should get the major plant items purchased this week.

I see Ben Goldacre's Bad Science site has a water section.

Tuesday, 26 August 2008

Oily Sludges

So it turned out that the heating and aeration of the oily sludges as part of the test for aerobic degradation broke the emulsion, where all other attempts had failed. Investigations continue.

I got an interesting email from South Africa this week, prompted by my page on package plant failures.

Steve Nicol of Wastewater Watch in SA produces an amusing name and shame newsletter for those he considers to be rogue package plant manufacturers in his country.

Design is proceeding on the upgrading of the failing pharma effluent treatment plant. We should be on-site in October/November to carry out the work.

Friday, 1 August 2008

Invest NI

We have been appointed for a second term as advisors to the Central Procurement Directive in Northern Ireland. Which is nice.

Emergency callout yesterday to problems on a groundwater treatment plant. Didn't take long to diagnose problems with a pressure sensor were inhibiting pump start.

No word back on the three tenders we have out, so had gone fishing. Was glad to be called away, it was hammering it down with rain, thunder and lightning...

Thursday, 24 July 2008


My French student is leaving today, so the supply of free assistance to my regular clients has ended!

The digestion experiments on PCB containing oily sludge seemed to give gently promising results, at least at 35C, so we may investigate further.

No problems with the turning down of the duff ETP's flow rate, so the client now has a bid for doing what is required to control the remaining non-compliances.

An enquiry for a metals removal plant came in this week, looks interesting, but the enquirer wants a free visit to discuss the job up-front, which may be problematic. I always find one can tell a serious from a speculative enquiry by whether the client will pay to meet you.

Wednesday, 16 July 2008

Troubleshooting and Experiments

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.

Monday, 7 July 2008


"Run your car on water": hxxp:// (url altered to avoid bumping their Google position) This guy's "invention" produces hydrogen and oxygen from water by electrolysis, and then you burn the mixture to drive your car. The site is full of anecdotal reports that this boosts fuel economy by 60%. This is basically a development of a long-discredited perpetual motion machine. This is even more stupid than my favourite crank site of all.

In case you don't know why, ignore driving the wheels, imagine a system where we just charge the battery. When we burn the hydrogen, we lose some energy as heat. Some of the energy goes to drive the alternator, which puts electricity in the battery, again with some inefficiency, lost as heat. The energy in the battery produces oxygen, hydrogen and more heat. We burn the hydrogen, much less than before due to loss of energy as heat...The energy obtained by burning the hydrogen is always less than the energy it took to make it. No perpetual motion, no energy from water, no two ways about it. Second law of thermodynamics. Look it up.

Then on the same day, I get a communication from from the get rich quick team at at hxxp://, offering the same thing. Now I know fuel is expensive, but wishful thinking isn't going to make it better.

I'm incidentally presently running my Landrover Discovery 200 TDi on around 40% soya oil at 87p a litre from Costco. That's a practical solution for cars that will take it. "Carbon neutral" and cheap too. Of course Costco soya oil is made from GM beans from cleared Brazilian rainforest, and is therefore evil Frankenfuel. LOL.

Thursday, 19 June 2008

PCB sludges

Things not looking too promising for the experiment set up on Monday to test anaerobic digestion of PCB containing oily sludges in Manchester. No evidence of any gas generation as yet.

Awaiting the order for starting sampling work to establish the bast way forward for the pharma client.

Continuing to review "Elements of Environmental Chemistry". Can't see a thing wrong with it so far...

Wednesday, 11 June 2008

PCBs in oily sludges, Environmental Chemistry, Chopper Pumps and truth comes to Homeopathy

Other than designing a solution to the problems of our new pharmaceutical client, I have been reviewing a book for The Chemical Engineer magazine, and looking at carrying out an experiment to determine how well anaerobic digestion might reduce PCB levels in oily sludges.

I am having difficulty at present sourcing a small chopper pump which can be controlled by inverter to provide a better, smoother feed to the pharma client's plant without blocking concerns. No problem getting one with 75mm discharge size or above, but the small ones don't have an over-rated motor, which is recommended for variable speed drive.

The book I am reviewing is "Elements of Environmental Chemistry" by Ronald Hites. Seems like a pretty good little textbook.

The oily sludges I hope to treat with AD have been a problem at a couple of sites I provide technical cover for for years now, and it is getting increasingly difficult and expensive to dispose of them. It would be nice if we can get PCB levels down to non-hazardous numbers by this process. The experiment is fairly quick and dirty, so we should have a rough answer by August.

Something amusing I saw today on the quackery front: truth in alternative medicine at last...

Wednesday, 4 June 2008

Design Errors: Static Mixers

A quiet sort of a week in the main. Cyril continues his research into treatment of PCBs in groundwater. I have been engaged with the pharmaceutical client mentioned previously on here.

They have what must be one of the worst effluent treatment plants I have ever seen in terms of fundamental design flaws. One of the biggest of them was the use of static mixers to mix acid and coagulant with effluent, which was pumped by diaphragm pumps. This showed a fundamental misunderstanding of the nature of static mixers in the system designer. Static mixers blend fluids across the body of the mixer. If you feed them with a pulsating flow from a diaphragm pump, and an out-of synch. pulsating flow from a dosing pump, you end up with constantly varying degrees of mix in the outlet flow. The normal rule of sampling at least 10 pipe diameters downstream to get 95% degree of mix no longer applies. Your pH probe for example will see extreme variation in measures pH, and instead of gaining control to +/- 0.1pH units as you should from a system like this, you will be lucky to see +/- 0.5 pH units.

Wednesday, 28 May 2008

Packaged Sewage Treatment Plants and BS EN 12566-3

More enquiries have come in from people with misbehaving small effluent treatment plants. I have covered some of the more interesting problems I have encountered previously with small plants on my website here.

Most of the non-compliant effluent treatment plants I see have been undersized, poorly maintained, and often worsened by the attention of unqualified "engineers" from maintenance companies.

From July of this year, BS EN 12566-3 replaces all national standards for sewage treatment plants for up to 50 population equivalent. Trading standards will enforce it, and it will require plants to have been tested to meet a set standard. The plants will therefore deliver a set standard at their rated population equivalent.

I have however only once been called out to a plant which was incapable of meeting its claimed standard by reason of incompetent basic design (that manufacturer shortly afterwards started to offer someone else's design, whilst not admitting that theirs was incapable of performing as claimed). The problem is more commonly poor specification, installation or maintenance.

What we therefore need now if for someone to make the specifier comply with the British Water Code of Practice in setting a conservative population equivalent for their development, and for someone to explain to the monkeys who work for maintenance companies that no amount of sucking sludge into a tanker makes you an engineer, and I'll be out of a job. I'm not losing any sleep about it. You can go to jail for claiming to be a Doctor, but anyone can claim to be an Engineer.

Wednesday, 21 May 2008

PCBs and Pharmaceutical Effluent

It's been a quiet week in the office. I've mostly been attempting to teach my French work experience student (Cyril) how to use a library to research an area of scientific interest. In this case, the subject of interest is PCB contaminated groundwater. He is looking as some problems with floating oily sludges on a treatment plant I look after.

It turns out that the French-speaking world have never heard of the Science Citation Index and Chemical Abstracts. I'm waiting to find out what their librarians recommend as an alternative.

Just as I write that things are quiet, I have received a call from some people I quoted six months ago to look at a problem on a pharmaceutical effluent treatment plant...

Wednesday, 14 May 2008

Water: Science and Pseudoscience

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.