[Gasification] Re: Lego /Instrumentation, Control and Operation

Tue May 23 23:38:14 CDT 2006

Hey Mike and List:

Why don't you explain to us more about that idea of yours... it sounds 
interesting... maybe you could find some great response in the third world 
especially in those little villages that are trying to gather some 
technology to conceive in a better way any productive process.

Since all of you have been discussing a bit or two about instrumentation, 
control and things like that, let me add some toughts to the thread 
regarding the criteria I think should be applied to analyze and choose the 
correct items for any given process:

In any industry, process or system you must count with a selected group of 
indicators, controlers and protections backed up with historical data so 
that they can serve as common base to the operator, supervisor, info analyst 
and the guy in suit that "runs the show" in order to achieve an increased 
operational quality and a better assestment of the process operation. This 
will allow you to have the correct info in the precise moment in order to 
have a clearer "big picture" of the operation in order to take good 
decisions based on data not influentiated by the subjective human factor. 
Also, it will allow you to change operational parameters given equipment 
limitations in order to achieve new equilibrium points that may allow you to 
have an operation with higher quality and reliability levels.

Good operational practices must have as reference the data gathered from the 
equipment's instrumentation and the data obtained in the lab, if any. The 
level of investment in these areas is a function of the level of importance 
and reliability of the equipment considered.

Buying sophisticated equipment does not imply that the facility or system 
will respond properly since the design parameters of the diferent areas that 
conform the system or facility  may not correspond with the new parameters 
to allow a reliable operation.

A control equipment will never correct the inherent problems of any given 
equipment (design criteria) nor the operational procedures. It will only 
provide estability and the posibility to vary the process in a + - 10 to 15% 
range over the plant, system or equipmet's operational rate. Nevertheless, 
the estability range is quite short in most processes so such operational 
rate should be respected. An operation at the lowest rate won't be 
economically supported by the plant or system and an operation at the 
highest rate won't be physically supported by the equipment.

As an example, in a sugar mill, where the equipment's interrelation is quite 
tight and limitant, the low or high margins are quite close. The only way 
out for a sugar mill is therefore to operate for a longer period at higher 
efficiencies. The instrumentation in such plant is always looking for the 
true equilibrium point of the system in order to pursue a higher efficiency 
in the process and in the equipment, with an ending result of higher product 
quality.

Now, good instrumentation coordination has to be done together with a good 
plant, system or equipment operation, both based in the employee's training 
and available resources in order to aquire an optimum work criteria. 
Instrumentation is a resource that may take process reliability to a higher 
level but it shouldn't be divorced from the operator's training.

Automatization imply making the operator a more capable person... it doesn't 
mean you have to take the person out of the process. Generaly among stupid 
plant chiefs there is an idea that because of instrumentation they might 
lose power over the decisions made that will affect the process ( They will 
lose the "magic" or the touch that made them so famous or recognized ), when 
what instrumentation will do is to allow them to increase their criteria to 
take good decisions and their direction skills by having the right 
information at the right moment.

The tip of the organizational pyramid of a plant, process or system is the 
one that takes decisions but this has to be well supported by the 
administrative and productive levels which at the same time are supported by 
a base of high production quality that will tune up with more resources, 
analysis, protections, etc. The base is therefore operation quality and it 
doesn't have to depend just on good human sense but also on equipments that 
offer measurments that will allow operational reliability and therefore good 
decisions to be taken.

So well... it is now time to hit the sack! Maybe we can discuss more about 
this in the future. I believe that control, instrumentation and good 
operation techniques from the big industries can be applied to little 
processes and equipments... but with the right approach... not just BECAUSE.

By the way, my brother in law told me that they have a huge gassifier in 
Tampa that is owned by Teco Group (I think...) and that gassifies 
charcoal... he showed me some pictures... cool stuff... lots of power being 
taken out of it... lots of taxes being cut because of it as well!!!!

Take care everybody...

Manuel

>Message: 3
>Date: Mon, 22 May 2006 23:02:07 -0400
>From: Mike Redler <redlerm at yahoo.com>
>Subject: Re: [Gasification] Re: Lego
>To: gasification at listserv.repp.org
>Message-ID: <44727B2F.4080104 at yahoo.com>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>Hey everyone,
>
>Great responses! Thank you.
>
>I've stored all the responses to this thread for later reference. I have
>no doubt that the knowledge will come in handy.
>
>The thing that I would really find rewarding is to keep some perfectly
>good computers out of the local dump. I'm a big fan of Schumacher and
>his ideas about intermediate technology and (more popular) "Appropriate
>Technology". I think that since old computers are abundant and
>potentially useful, I'd like to help add the last remaining ingredients
>- a conscientious objective and some creativity.
>
>...anyone interested?
>
>Thanks again!
>
>Mike
>
>Manuel Escamilla wrote:
> > Mike:
> >
> > Also you could check the Siemens series. As a student I got involved
> > with Siemens, Omron, Foxboro and ABB and believe me Siemens with it's
> > cool STEP7 MICRO WIN interface is the easiest in the market when it
> > comes to control and questioning the process. If you want top of the
> > line stuff you should go to Foxboro which is the prefered brand for
> > companies such as Teco Group.
> >
> > I do believe that even though the type of control you need may be
> > achieved with digital signals, the type of programming you need is non
> > secuential, which is the one used preferably with digital. PID control
> > is more reliable, estable and the programs are smaller than those
> > using secuential runs.
> >
> > You should also work just with current normalized signals which are
> > more stable, do not get affected by medium external fields nor heat as
> > voltage signals do.
> >
> > Good luck with those... automation is quite fun although sometimes I
> > felt like half of my face was going numb because of the problems that
> > secuential language brought to me (which PID didn't).
> >
> > Take care
> >
> > Manuel
> >
> > PD/ The good thing about all the brands is that they are now working
> > under EARTH protocol and some international IEEE aproved language
> > which is quite easy to understand since it is mostly graphical. Go for
> > the Siemens!!! The software is free!!!  =)
> >
> > Also, for those that got interested in the work I was conducting a few
> > months ago, let me tell you all that I just finished it and you can
> > contact me if you want to see what was concluded.
>
>
>

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