Liquid Analysers pt 1

We invited Nick Crowe, our Product Manager for Analytical Products, to debunk myths around Liquid Analysers. In part 1 of this series Sean asked him  whether the maintenance-free analyzer is a myth?

Transcript

[00:05] - Sean 
This is a Yokogawa Australia and New Zealand podcast, welcome to the Yokogawa debunks conversations with industry experts to demystify misconceptions we hear in process instrumentation and industrial automation. I'm your host, Sean Cahill, and thank you for joining us again. Now, in past episodes, we've had interesting discussions around cybersecurity, gas chromatography and wireless instrumentation. Today's topics moving on to that of liquid analysers and more specifically, the myths involving their maintenance. Now with us today. 

[00:47] - Sean 
We've got Yokogawa’s Nick Crowe. Nick has been product manager at Yokogawa for Analytical Products and has been with the company for over 15 years. His domain expertise in the analytical business is second to none. So welcome today to the podcast, Nick. 

[01:02] - Nick 
Hi, Sean. Yeah, thanks for having me on. I'm really looking forward to going through these myths with you. 

 
[01:09] - Sean 
Thanks Nick. I wanted to start with our conversation by just posing a couple of questions to you in line of some of the myths that are out there. And the first one is, is whether the maintenance-free analyser is a myth, you know, is there such a thing as a self-cleaning self-calibrating analyzer or is that a unicorn? 

[01:29] - Nick 
Perhaps a unicorn is a is a good way to describe the maintenance-free side of things? Yeah, I think really the idea behind a maintenance-free process analyzer is just as much of a wish as it is a myth. But really, we can understand where the requirement is coming from. We see in industry at the moment, there's a great focus on operations trying to reduce the amount of maintenance in the plant and perhaps they can be quite a few drivers for that, such as we we don't want to have operators and maintenance staff active in a in a live plant. 

[02:05] - Nick 
Perhaps there's hazardous environments that we we don't want them to be working at. But also there's a push to reduce the the operating costs on the plant. And maintenance can be a large part of that. As we also know, there's a lot less staff available and the staff that are available don't have those years of expertise to back them up when they're out in the plant. Now, unfortunately, analysers are quite a maintenance-intensive instrument. So it's quite common for us to see or hear the requests for the self-cleaning and self-calibrating system. 

[02:41] - Nick 
And, you know, such devices are available in the marketplace. However, after implementation, often the focus for maintenance moves away from the analyser itself to maintaining that self-cleaning self-calibrating system. So I think the reason is when we're using a liquid analyzer in a nasty process, the analyzer requires much more maintenance than it would in a clean process. So it seems to be the nasty processes that attract the attention of the self-cleaning self-calibrating system. However, unfortunately, they're just not suited to that nasty process. 

[03:22] - Nick 
They they rely on o-ring seals and smooth operation. And when you combine that with a process slurry or something like that, it just doesn't work together. 

 
[03:34] - Sean 
So I can certainly see why such a such a myth persists out there. I mean, you know, why use such a complicated device and why not just use a maintenance-free sensor? 

[03:46] - Nick 
That's a very good point. And with some measurement parameters, you know, this has almost become achievable. With analytical sensors, the real challenge is that we require the element of the sensor to be in contact with the process. Therefore, that process has an influence on what's happening with the sensor. And as we mentioned, nasty processes require a lot more maintenance. The nastier the process, the more effect it has on on the sensor itself. So some measurement parameters such as conductivity, have developed to a point where we can almost achieve maintenance-free, so with conductivity, it's common to use a method known as inductive conductivity. 

[04:30] - Nick 
And when we do that, we can protect the analyzer elements behind a plastic housing. So it's isolated from the process. However, a lot of plants will still have a standard operating procedure or an S.O.P, which means that these things have to be checked and maintained periodically. If we look at other times like pH or dissolved oxygen, they can't be protected behind plastic and they have to be in contact with the process and pH unfortunately is one of the most common analytic measurements, but is also one of the most maintenance intensive. 

[05:04] - Nick 
So we have to get in there. Unfortunately, some people are simply looking for a way to to avoid doing maintenance at all, but really, as I say, it has to be done. And if you're not doing it, you know, you really risk losing the information. The purpose of the measurement in the first place, it was obviously put in there to to contribute to the smooth operation of the plant. And if you're not doing it, you don't know if your sensor is responding to changes and so on. 

[05:32] - Nick 
So it could be detrimental to to your operation. 

[05:37] - Sean 
I can certainly see that, you know, reducing maintenance is going to be priority for many, I mean, you know, most sites, they are struggling for personnel there. They have a lot of pressure on them from a budgetary perspective and just time in general. So is there any solution to to to this problem? 

[05:55] - Nick 
Kind of almost there is I suppose the user should always try and remember the analyzer maintenance will have to be done. It's unlike a pressure transmitter or a magnetic flowmeter or something like that, where we we tend to have a set and forget type attitude. With analysers we have to do as we say. And the second thing that we we need to remember is that nobody seems to want to do it either. You don't very often find analyzer technicians, they're pretty, pretty rare. 

[06:27] - Nick 
So really, what what we should try and focus on is matching a sensor to the process. So vendors, including us at Yokogawa we have lots of choice for different sensors and we do our best to try and match that to the process that you have so that we can try and minimize the maintenance. Also, you need to remember that it has to be accessed, so don't put the sensor in a place where no one can get to it, or if you need to have a scaffold or something to set up to get to it, because some of these measurements can require maintenance daily. 

[07:03] - Nick 
Other measurements might require maintenance every month or six weeks or so on. But it's also important to consider the capabilities of your maintenance team as well. So we need to make it as easy as possible and as simple as possible. As I mentioned, no one wants to do it. So if we can try and design a system with consultation of the end-user to try and make it as easy and as User-Friendly as possible, hopefully that maintenance will be done and you'll get satisfactory or pleasant results from your Analiser. 

[07:36] - Sean 
And there's some very sensible and, you know, good good advice and good guidance there, which, you know, hopefully our listeners today are going to be going to be able to take away as valuable. But coming out of that, I guess, you know, now that we know that sensors do actually need some maintenance, what generally is the maintenance frequency for the sensor? 

[07:55] - Nick 
Well, that's that's a really common question that we get. And it's possibly the hardest and perhaps even impossible to answer. But we often get asked this when people are considering installing a new analytical measurement or perhaps when someone's hoping they're going to replace another one that they're dissatisfied with. As I mentioned, it's really not possible to answer. We've already talked about how the sensor has to be in contact with the process, and we all know that each process is different. 

[08:27] - Nick 
So each process is going to affect the sensor in a different way. Therefore, maintenance intervals are going to be different as well. Perhaps a hot process, for example, will increase the frequency that you're likely to have to perform maintenance. An abrasive process as well might increase that frequency as well. So I really generally try to advise people to start with a scheduled maintenance routine, maybe do it weekly, for example. And then each time you do that maintenance check for Drift, how far is drifted from the last time you did the maintenance? 

[09:04] - Nick 
And then that way you can eventually start to determine if you need to do maintenance more frequently or less frequently. Some analysers in the market, including ours, can actually do this for you. They will determine if you're maintaining enough or if you can prolong the period between maintenance. It just depends on how you record the maintenance and how you perform calibrations and things. 

[09:27] - Sean 
So I think it's easy to say here that that it is a relatively complicated solution here. However, that with the rights, maintenance routines and schedules and checks in place, it can actually simplify itself over time. And I think this is a great piece of advice for for people in putting together their schedules and the maintenance routines. And I think we've only just started to uncover some of the truths behind these misconceptions about the maintenance-free sensor. And there's still an awful lot more to cover. 

[09:58] - Sean 
We'll finish this session here now, but please join us in part two of this series of Yokogawa Debunks where Nick will continue busting the myths with us. 

[10:07] - Nick 
Yeah, thanks for having me, Sean. It's been a pleasure. 

[10:10] - Sean 
Thank you very much for listening.