Monday, March 25, 2013

Pump and Mixer Reliability is All About Buying Quality Says Landia

O.K. so as a process engineer I am biased, you might say. I don't have to pay high initial plant installation costs myself, and a lot of plants simply would not have been built at all if the owners had not been seeking to build them on the lowest conceivable budget.

But, talk to those in the UK anaerobic digestion industry with operating plants and within a short time you will know that pump and mixer reliability is a big issue.

That's why I am delighted to publish here this press release from a supplier that is committed to quality, and is prepared to invest in external audit services to provide the rest of us with good evidence of their internal systems, to back up their claims.


Pump and mixer quality counts says Landia with new 100% UVDB quality achievement Landia UK, the leading pump and mixer manufacturer, has achieved a 100% pass rate for quality in its latest UVDB VERIFY Approval.
According to Landia UK Director Hugh Vaughan, a maximum quality score in this independent audit by Achilles clearly makes a statement about the excellence of the company’s products, procedures and ethos.
“The UK’s biogas industry does get some flak about AD plants that aren’t working properly. Sometimes this is down to very poor ‘chuck in anything and everything’ feedstock choices, and it can also be down to using equipment that just isn’t fit for purpose”.
He added: “We hear plenty from the industry about wanting to improve biogas yields, but those citing poor performance are invariably the ones who’ve specified equipment such as pumps and mixers that aren’t of a good enough quality to work properly in an AD plant. There’s also plenty of kit out there that has been dressed up as supposedly suitable for the UK biogas industry, but simply isn’t capable – and/or doesn’t come with any proper maintenance or spares back up”.
In addition to its 100% UVDB VERIFY quality approval, Landia also achieved (for OnSite Assessment) 98% for Health & Safety and 93% for Environment.
Hugh Vaughan continued: “In addition to quality, health and safety should be paramount for AD owners and operators, so they need to look very closely at finding those in the supply chain who have the proper credentials. Not a difficult task. This would then in turn enhance the reputation of the industry for everybody’s benefit”.

01948 661 200

Waymills Industrial Estate
SY 13 1TT

Wednesday, March 20, 2013

Verder Chemical Dosing in the Spotlight

Verder Chemical Dosing in the Spotlight

In this article Philip Brown, Project Manager for pumping solutions at Verder UK, explains the chemical dosing process, and how dosing techniques are commonly applied by Verder to the popular chemical dosing functions of pH buffering and phosphate removal.

Chemical Dosing

Chemical dosing is the controlled delivery of a chemical into contaminated water, sewage or sludge–like fluid, usually as a pre-processing method. It is frequently used during sewage treatment, and as part of the anaerobic digestion process for making energy from waste. Chemical dosing is also used when treating industrial effluents to remove contaminants, before it can be returned to a natural watercourse.

The Dosing Process

A set of chemical dosing equipment mounted on a "skid" (a relocatable metal frame) is the most effective way build a chemical dosing system to dispense chemicals. Most skid mounted assemblies use at least two peristaltic or reciprocating dosing pumps. These are attached to pipe manifolds and the whole unit is usually protected within a cabinet. 

In such arrangements one pump acts as a duty standby component to ensure the dosing process is uninterrupted in the event that a wearable component fails, and the system needs to be serviced. 

Normally, chemical dosing systems are set up with pumps and valves to accurately and automatically control the dosing process to inject a chemical into a pipe or vessel at a predetermined rate.

pH Buffering

Chemicals such as sodium hydroxide or lime are dosed in conjunction with pH measurement - a process known as pH buffering to ensure that the process runs in the optimum pH range for the reactions of the chemical process to take place. 

For sewage works systems the amount of buffering will vary according to the time of day; for example at a high rate in the morning when people use the toilet or bathroom, at a lower flow rate during the day, and back at a high  dosing rate in the evening when they finish work. As a result, dosing pumps need to increase the amount delivered at these peak demand times and reduce it during the hours of sleep, producing a diurnal, cyclical flow. 

Removing Phosphates Using a Unique Product Developed by Naiad Aquatic Water Services

Introduction of an iron-based chemical solution like ferrous or ferric sulphate or chloride can very effectively remove phosphates which are pricipitated out during a settlement stage. Alternatively ferrous sulphate can take the form of copperas crystal, a by-product of the pigment industry, which can be mixed in a tank with water in a unique patented process available from Verder, and provided in conjunction with Naiad Aquatic Water Services. 

Working in an exclusive collaboration with Verder UK, Naiad Aquatic Water Services, has developed a range of chemical dosing systems including the Naiad Copperas Saturator. 

The latter was developed in partnership with Thames Water’s R&D section to provide a cost-effective alternative to liquid dosing. Naiad chemical dosing systems incorporate feed-back and load profile control options, and enable process optimisation for phosphate removal and septicity control. When used to dose chemicals into sewage for phosphate removal, Verder's equipment ensures that phosphate residuals in the final effluent consistently meet targets, and odours are minimised. 

Verder takes pride in delivering pumping solutions that are designed around the needs of the customer, not off-the-shelf packages which are made-to-fit all, but which seldom fit any site's needs perfectly. Verder points out that their customer feedback regularly shows that the quality and robust nature of the company's end-product is superior to their competitors off-the-shelf solutions.

Verder has found by experience that the best outcomes come from their practice of involvement with engineers face-to-face, and by setting-up meetings to discuss their client's requirements in detail. Whether the setting is a boardroom, or on-site in "boiler suits", they place a high priority to always providing a professional service built upon courtesy and respect between contractor and customer. 

Philip Brown points out that ultimately, it all boils down to Verder's passion for saving water utilities as much money as possible, while at the same time always providing them with the most reliable and robust equipment.

Visit Verder's website for more information at

Author: Verder
Phone Number: +44(0)1924 221 001

Friday, March 08, 2013

UK Biogas Plants Exceed 100 And Hit Trouble

100th UK AD PlantThe good news is that that magic number of 100 anaerobic digestion plants in the UK has now been exceeded. In fact, if you visit the AD Info "Official Anaerobic Digestion" website, you will find that their list of 100 does not include a number of categories of AD Plant, such as Water Company sewage sludge fed plants. That means that the true number is probably more like 125 already, plus even within their categories we know of several unlisted digesters. Even so, the UK is still a long way behind Germany and other EU states, so we maybe should not be proclaiming this achievement at all? On balance I think the UK is right to give itself a small pat on the back. But, let's not forget that Germany has two to three thousand AD Plants in operation. Yes. That is thousands! And yet, the proportion of UK plants that are organic waste fed, as opposed to energy crop, is vastly higher than in Germany, and that in itself is arguably far better. It is better for the environment and the avoidance of potentially reducing food production and raising food prices. So, the UK AD industry is correspondingly much "greener". The following is the press release that prompted this article:

Anaerobic digestion plants hit the 100 mark...

"The number of anaerobic digestion (AD) plants in the UK – excluding waste water plants - has passed the 100"
But, unfortunately, as the UK biogas industry is expanding it is also beginning to hit trouble with odours and pollution. The Poplars Landfill Anaerobic Digestion Plant was last week in the News for continued odour complaints from local residents. Hopefully, that will be a thing of the past , after the plant operator brings in new measures to combat those odours this month. Watercourse pollution is the "trouble" which one AD Plant oprator has been "hit" by. Yet, one wonders whether the method being used for pumping the digestate at the time was wise, given the risk from pollution. The following is an extract from the article, to which we refer:

Somerset company fined for polluting stream with waste from anaerobic digester... 

Waste Management World
"The pipe had broken free while digestate was being pumped from the anaerobic digestion plant. The pollution flowed into a trench and eventually into a stream which flows into the River Parrett. Approximately 60 tonnes of liquid digestate was lost ..."
The River Parrett is slow flowing through the Somerset levels so the potential damage to river ecology is large.

Friday, March 01, 2013

What Every Biogas Plant Engineer Should Know About Contracts

O.K.! In our headline we have to admit that we changed the title to add in "Biogas Plant Engineer", and the course we are recommending here is a general training course, aimed at all engineers. However, the IChemE Forms of Contract are particularly useful for those like Biogas Plant Engineers and Managers, who need a form of contract which is designed for a process plant.

The ICE offers similar courses, but for biogas plant contracts they are generally not nearly as good, because they are all about getting a structure built, and nothing much beyond that.

Biogas Plants (Anaerobic Digestion Plants) are above all process plants. Process Plants are different. A bridge is finished and providing value as soon as the red-tape is cut on opening day, and the road over it, is opened. 

A process plant is different. To have a process plant built and sitting there is no good to anyone. A process plant like a leachate treatment plant, has to be commissioned, and working to produce the treated effluent to the quality specified by the discharge consent.

There are IChemE Forms of Contract for process plant contracts which suit every type of financing as well, so attending this course is really important for those in the leachate treatment industry, and if you are active in this area, we recommend attendance.

The details of the course follow:
The "What Every Engineer Should Know About Contracts" course will provide you with a
detailed understanding of contract law as it relates to engineering and construction contracts. It is taking place twice in the UK this year: 1-2 May in Rugby and 15-16 October in London.
Suitable for engineers of all disciplines, the course examines the law of contract and of tort within which engineering and construction contracts are made and operate.
It also looks at:
  • the structure and essential contents of these contracts risk allocation and its links with payments
  • the role of the contract administrator why the various standard forms of contract say what they say 
It is ideal for managers involved with contracts, particularly those who have moved into a procurement, project or contract management role, as well as engineers who are developing their skills across the range of business activities.

Click here for full course details and to register

Download the course brochure

You may also be interested in: 

IChemE Forms of Contract

12-13 June 2013, Redcar, UK
19-20 June 2013, London, UK

Helping those who will prepare, tender or manage a contract using the IChemE forms to understand their structure, main provisions and features, and the key differences between them. Fully updated to cover the new 2013 suite of UK contracts. Find out more here.

Please note that this is not a sponsored recommendation. We make no money from the course promoter if you attend.