Measuring the Online Conductivity of Condensate Water for Boiler

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i m working in a sugar mill, you know that in sugar process the steam circuit is a closed circuit, we use steam pressure for running the steam turbines for power generation and mills roller driving, and we are using exhaust steam of turbine for process house, like evaporaters pan stations and then the condensate of steam use for condensate water as feed water for boiler. there was risk of leakage of cane juice in evaporaters pains and juice heaters tube, so for safety for condensate contamination we need to install conductivity sensor on 6'' line of condensate water that was going in deareator tank of boiler having pressure 1.5 to 3bar and temperature 95C to 110C, so please suggest the right sensor and installation place, i also check through search engine, but needs more and practical information of experts

I don't understand how measuring the conductivity of your condensate water will tell you if you have picked up cane juice contamination. Surely the juice compounds are non-ionic species that will not affect the conductivity of the condensate? Unless of course there are some ionic species present in the juice that can act as a "tracer." More information needed!

You might also want to invest in a controlled sample cooler for that conductivity, as your temperature is rather high, and can damage some probes from certain vendors. Sample conditioning modules are usually set up with an overtemp switch to block sample flow when the temp is too high to continue. Swan makes hands down the best online water measurement/analysis instrumentation for the plant environment, and since it is Swiss manufacturing, they guarantee product support for 10 years beyond the announced obsolete date of the model. You will not find that kind of support for anything American, much less Japanese.

please note the 6'' line pressure of condensate water is 1.5 bar to 3 bar and temperature is 95 to 110C,

"Sugar in return condensate from Evaporator station has conductivity."

Why?

Because sugar in solution certain impurities that are conductive and allow the passage of electricity ( Conductivity, if you read the theory and understand it, depends on any free ions in a solution to carry current)

If you can't accept this, please do some Chemistry / electricity research

Gosh, thanks for the lecture. FYI I have a B.Sc. in Chemistry and relevant to this question, spent 2 years working on the electrodeposition of aqueous polymer solutions and 2 years research on H2/O2 fuel cells and Zn/Air batteries. So please feel free to fill me in on why a non-electrolyte such as sugar, conducts electricity. What are these "impurities" and from where do they arise? Thanks.

Just a shot in the dark here, but since:

1. cane sugar is extracted from sugar cane, and
2. sugar cane is a plant, which during its growing phase is a living organism, and
3. living organisms have biological processes, and
4. biological processes frequently rely on ion transfers.

Would it not make sense to find some of the ion carriers, such as NaCl, as trace contaminants within the 'cane sap'/cane syrup?

I don't mean to step on any toes, however, the curriculum vitae you provided shows a strong affinity for 'inorganic' chemistry (polymers may or may not be 'organic' in the chemical sense, that is, containing at least one carbon atom, but except for a few cases would polymers be involved in biology) and the situations you have been working in are, for all intents and purposes 'spotlessly clean.' Biology, on the other hand, is very dirty and messy, and you're always dealing with contaminants. 'Pure' blood plasma is plasma with a parts per ml count of red blood cells, white blood cells, platelets, etc below the 'threshold value' where they are considered enough to provoke an immune reaction from the recipient, 'pure' cane syrup still has bits of the cells from the sugar cane that was mashed up/shredded to extract the syrup, and you do not want to know how much rat butt meat is allowed in a hot dog by the FDA. (even kosher hot dogs may contain small amounts of rat, which is non-kosher, simply because it's too small to detect with the current methods, and the poor shlamiel who was running the grinder turned his back on the process because he had to sneeze, and while avoiding contaminating the meat with his own biology, didn't see the one rat who fell off the overhead rafter into the machine.)

There may well be ionic contaminants in impure sugar - that's what I'm trying to find out. As for your rat rant - the mind boggles.

I may have gone a little over-the-top with the hot dog analogy.

That's one problem with growing up in the Theatre, I can never be sure when I'm being ... (goes into a Hamlet 'alas, poor Yorric' pose) ... overly dramatic in conversation.

rat butt meat? Really. That is just beyond the pail. I thought we were talking condensate, not I gotta unvisualize rat butt meat.

Okay, I did go too far into hyperbole there, I apologize.

Minor quibble, though, the term is 'beyond the pale' not pail.

http://en.wikipedia.org/wiki/Beyond_the_Pale

So when are you going to complete your "education"?

You hold a Bsc degree in Chemistry , right?

Just so you are in the frame, so to speak ( I never like to quote my stats) I hold 2 x Doctor of Philosophy Degrees: Engineering Instrumentation and Engineering Management. I also have an Mba in project management and a 2nd Mba in International Business Management. These are irrelevant to the, 'hands on' 30 years' experience in Sugar Milling Instrumentation out of a total of a 50 years in C&I. ( Boilers, powerplant, analyzers etc etc are my fields of activity.

I have designed , implemented and commissioned sugar mill Instrumentation in several countries using Stand alone Micro-processor, PLC and DCS systems.

I lecture in some 8 countries here in Africa ( OK so you live in the "real" world)and all course compilation and presentation I do myself.

Your whining about Chemistry when you have virtually NO practical field experience is embarrassing to your image. Do some honest to God research into the science of Sugar Milling and then ask some relevant questions.

Regarding the furtherment of your 'career' : My first suggestion to you would be to take a course in Humility. When you are done with this,perhaps you will have learned that respect is earned, not some piece of paper you so glibly brag about.

Sorry, but you asked for this.

I'm 73 years old and retired so will not be furthering my formal education, but thanks for your suggestion. I'm not going to give you my life story, but they include water treatment chemical sales and service, x-ray, NMR, IR and optical emission spectroscopy sales and marketing. I find your remarks rude and offensive and have reported them to CR4 Management. As a newcomer to CR4 I don't think throwing your weight around will make you many friends.

P.S. You still haven't answered my question about why sugar solutions have a conductivity.

Speaking of humility, and earning respect, you might not want to com on so strong with your early posts. You may be internationally recognized as a genius and miracle worker, but until we get to know you better here, all we have is the tone of your posts to go on for determing what sort of personality you have. Are you sure you want to present yourself as a Charls Emmerson Winchester III sort of character?

I think I waited until I was about a hundred comments in before I started wisecracking and letting my slightly off-center sense of humor show. By then people had gotten used to me, and I had a GA or two under my belt, so I felt more comfortable with saying things that some people might take as grandstanding or offensive. I had already shown that I was able to 'play well' with the other people here, so I could risk hurting feelings since I knew the people here would see my apologies were sincere.

And to the person who gave me a GA for this:

Thank you, I try my best to be helpful and informative here, and baring that, I at least try to be entertaining and to ask questions that will help those who know more than I on a subject to work out the answers.

It's a team effort, and deep down inside we're all just fellow nerds (To some degree or another, I literally cannot conceive on anyone with no trace of nerdiness ever being attracted to Engineering, No cheerleader or athlete would look at a motor, watch or electronic gizmo and say 'Cool, I wonder how it works,' they'd be too busy 'being popular' to think about anything else.), I do what I can to help.

Well, at the risk of being shunned because I have no formal degree (though considerable time in several different colleges and 45 years in various industries) I'll have to go with energyconversion on two counts.

1. A solution of pure water and sugar will not, by themselves, conduct electricity.

2. CVs don't mean much here. A track record with some history behind it is worth far more to the members. Manners will help, although I have none and make no excuses for that.

3. Newcomers should show a little deference to established members when first entering the murky waters of a new forum. They'll find the swimming more pleasant later on.

I know, that's 3. But, who's counting?

But we are not mixing pure water with "pure" sugar here now are we? I was under the impression the OP was talking about a sugar mill, cane juice, etc. Cane juice does include some electrolytes.

OP needs to get an auto-ranging transmitter with at least one output loop, and probably a couple of output relays to alert operators when things are not right. There is a learning curve for his process, and it is up to him to get on the horsey and ride it. Not us.

I will agree that sugar itself is non-ionic. That is a non-brainer. However, sucrose sugar breaks down to fructose and glucose, and aldoses as those are known as "reducing" sugars susceptible to oxidation. Once oxidized, the end group is now a carboxylic acid, and depending on the pH, it will be present as a carboxylate ion. I agree we are bit touchy about the wording, and the devil is in the details.

Sugar mills represent anything but a pure chemistry situation, so there must always be impurities in the process that are very undesirable in the steam circuit. I think conductivity monitoring is a good idea, or every Oxidation-Reduction Potential (ORP) might be of some use.

What I don't get is why people get all huffy about the confusion of wording when we are all just trying to "feel the elephant to see it."

Just repeating what the new guy with, "2 x Doctor of Philosophy Degrees: Engineering Instrumentation and Engineering Management. I also have an Mba in project management and a 2nd Mba in International Business Management", and who took offense at being called a "brash newcomer" said.

Me? I don't know from nothin'.

[ What I don't get is why people get all huffy about the confusion of wording when we are all just trying to "feel the elephant to see it." ]

Perhaps it's just that people are concerned that they'll be the ones to feel that area below the part that feels 'like a little rope.'

I'm going to stop the analogy there, I do NOT want to be the next person to step onto a metaphorical 'land mine.'

Unintentional palpation is never a pleasant experience. Nevertheless, it is precisely what science is built upon. So probe deeply, my friend, you may discover something up there. It may not be what you were seeking, but it may find its uses.

Well good for you.

All plant juices contain small quantities of electrolyte, certainly not as much as blood serum, but you can find sodium, potassium, etc. and also some small amount of chloride. Plant juices also contain not insignificant amounts of organics compounds such as organic acids and some nitrogen compounds that may be ionized at various pH conditions.

Do you know what range you can expect to see? For very low conductivity (like under 1 uS), look for a "resistivity " meter for example. Most any instrument will have a 4-20 mA loop for conductivity and maybe one for temperature.

You may want to talk to a salesman. Hach is one company, Knick is another...two of many.

Bob the water geek

Honeywell does conductivity. Its 4973 insertion probe is rated to 140 DegC up to 16 bar. There are a couple different transmitter/ analyzer/controller options. They're industrial, not lab designs and priced accordingly.

If you wish to use what I consider, "Best in Class" then opt for the new Yokogawa system.

It has unique features such as multi solution temperature compensation.

If this is confusing, please accept the fact that temperature compensation relies on what is called the Beta factor; it is normally based on an NaCl solution as a reference. There is a simple methodology for determining this. Google it and read how.

However, plant chemical fundis might not find this ( NaCl) to be close enough to the solution under measurement. Yok offers 2 solution alternatives.

It is also programmable via a sealed touch screen display in 6 languages. Couple this with a toroidal (or doughnut ) probe and the unit can be calibrated in Micro. milli Siemens as well as BRIX. ( Which for Molasses blow up tank application is perfect as it has 2 x 4-20mA outputs, the 2nd being temperature. Great as it allows Brix and temperature control from a single , but multi output sensor

Actually, all this is fairly standard. Electrodeless conductivity may not a good choice unless his process has a fouling component. It depends on what his conductivity range is, and we don't know that yet.

I agree fully with #1...Yours is a somewhat pathetic request.

Please close the door after you. Thanks.