derwent james safety equipment & consultancy

Safe & emission free sampling of hazardous liquids, gases & liquefied gases for the UK process industry.

Tel: 01332 673700

process industry safety

Better than an open pipe and tundish

Better than an open pipe and tundish

Are chemical manufacturing companies still sampling hazardous chemicals in ‘open’ ways.  Sampling  chemical liquids with exposure to the operator and the environment when safe, simple, sampling techniques are readily available. There are many ways better than sampling with an open pipe and tundish.

Although other preventative measures are often put in place (additional PPE, enclosures, and reducing sampling frequency) I am still often called to site to offer advice and improvements to help reduce emissions and spillages whilst still maintaining the required accuracy of the sample.  This can be relatively simple with a Dopak sampling system . So why haven’t all chemical sampling applications with open ends been resolved with a system such as a Dopak system

It’s probably a combination of costs versus benefit and companies trying to achieve a better result with technology and equipment already on site. Budgets are tight, timescales are short and it may not be possible for a plant to shutdown to even allow for the installation of the sampling system.

“We’ve always done it that way.

“Why do you need one of these ‘new’ sampling systems…I used to wash my boots in benzene

It’ll block up, they always block up

It’s only a valve at the end of the day

This new sampling system takes ages to collect the sample

It splashes a bit but we need the sample

Just a few of the comments I’ve heard over the years…all valid to a point but it seems its easier for some to do nothing than to improve a system which hasn’t caused any major issues…yet!

Do we wait until an operator is splashed, burned or injured more seriously before an improvement to a sampling system is given the go ahead.

Is the sampling system one of the very few parts of the plant where the operator comes into direct contact with the liquid being sampled?  At all other times it seems the liquid is contained within pipes and tanks or dry break couplings are used to prevent spills from hoses (you’d hope!) it is only the sampling point (maybe you know others?) where the man or woman charged with taking the sample has to open a valve allowing the hazardous liquid to sampled – so surely in this case the absolute best available equipment should be made available to enable this operator to take this sample in the safest possible way.

So, sampling then…do you take samples? Does your plant require samples to be taken, does the existing sampling system you use meet all the necessary requirements for safe practice.

Sampling hazardous chemicals can be achieved with a bespoke system for chemical sampling…many of these systems however are fairly straight forward and easy to install so why wouldn’t you use it?

On the most basic level you may have an open pipe and a tundish.  You open the valve allow the hazardous liquid to run out of the pipe and into the tundish maybe 1/2” a metre below, great…you can get that representivity you need…let it run for a few seconds to get a fresh sample.  But.  What about the emissions to atmosphere, spillages to ground, splashes onto local equipment, or worse still splashed onto unprotected operators?

This is probably the most common application I have seen in the 25 years doing this job.  Does that open pipe and tundish approach still exist? It’s easy to contain the sample, protect the operator and provide a representative sample. If the liquids relatively free flowing, below 40 degrees C and 8 bar pressure or below then the Dopak DPM in system purge configuration will do the job.  No need for an enclosure, no need to run the product to drain.  A contained sample every time with the safety of the operator assured.

Dopak have seen this and many other applications before.  All tackled successfully worldwide by Dopak systems.

Other applications may be described as such…

“The liquid is higher than 8 bar” – Dopak System 23

“Yes it’s a liquid but at sampling temperature it’s viscous” – Dopak DPJ

“The liquid we need to sample is very hot” – Use standard cooler from Dopak or cooling jacket.

Gases and liquefied gases – Dopak S23G and Dopak S32LG

Are Dopak systems off the shelf?

No. Dopak systems are not off the shelf.  You need to plan their installation with the following in mind;

The design process (the bit where you talk to us about what you need) can be very short or very long…it depends.  When the final specification is agreed we’ll prepare you a quote…this is both a technical description of the system you need, the delivery time of that system and of course the price for it.

If you’re happy to proceed then you need to place your order with Dovianus BV in The Netherlands (this is the name of the company that manufactures Dopak systems). If Dovianus have dealt with you before and you have an approved payment structure in place then great…all systems go.  IF you’re a new client who Dopak have never dealt with before then the payment terms need to be agreed.  This agreement must be reached before the order proceeds.    This bit doesn’t take that long so provided all is agreed the order can be entered onto the Dopak order processing system.

Next step…engineering.

Your order is passed over to the Dopak engineering department where the assigned Dopak engineer will produce an engineering general arrangement drawing for your approval. It is only when Dopak receive your approval of the drawing that manufacture and ordering of parts can begin. If changes are required to the drawing then no problem, send the drawing back with the comments, the changes can be made and then the drawing is re-issued for your approval.

After drawing approval

Once the drawing is A1 approved by you then the system can be manufactured and any special materials ordered.  Once complete the system is tested and certified and is ready for shipping or collection.

On site.

The sampling system is delivered to site ready for installation.  If you require any further assistance during this process then contact Dopak or the UK representative Derwent James ltd who will be more than happy to offer advice and support.

Sampling can be simple with the right equipment, so do it safely. Safe, simple, sampling.  Obviously better than an open pipe and tundish… so, what are you sampling?

Start your sampling journey here by contacting us for a no obligation discussion about how you can reduce hazardous sampling emissions and make your daily sampling safer for your operators.




Share this

Back to Latest News

Providing outstanding sampling equipment, consultancy and expertise for your company.

Copyright © 2024 Derwent James Ltd | HTML Sitemap | Privacy Policy
Web design & SEO by Website Design Derby Ltd

Skip to content