UF Machine!

[balerjoe 0]

Part 1 of my exercise is Overview of Project. Ok we are going to build a RO (Reverse Osmosis)Processing Milk Machine. This will be a single pass setup. The hard thing is we will be doing this under a cold process which raises the difficulty level. The objective is to take Raw milk extract water from it so it can be transported in high concentration. Raw milk coming from dairy not processed. When machine runs 80gpm goal with proper ratios. This machine will consist of 24 membrane vessels. Each vessel contains 4 membranes being connected by interconnectors. To maintain a proper setpoint ratio we need at least 400-600 psi. To accomplish this we will need 10hp motors and proper pumps on each vessel. Lets use 3phase 480 with VFD's for all motors. We need throttling valves on the back of each vessel. To ensure milk is kept below 45F the membrane vessels have cold water jackets to maintain temp. These will have to be controlled by valves and cold water press. Lets maintain 41F on temp. Hot water will need to routed to all vessels for the CIP process. Lets shoot for a temp machine max temp of 160 w/meduim pressure steam(160-180psi). We will need a balance tank to ensure no air in the process. Compressed air for all the air actuated valves on the machine. We will need to divert to drain on all poor quality product. Poor quality not having proper protein fat ratios. From a control stand point will need HMI showing all setpoints. where the milk will be stored is another project. So I keep this as simple as I can. Control wise we could anything from plc5 to controlnet. There are so many machines that support this should I spec all of these out as well? Heres my first of many post on this project. Help me out guys am I on the right path. Do I need to do a drawing?

[TimWilborne 108]

Wow weren't you just asking about Plc schools? Is this the first chapter? What happened to the basic? (XIC, XIO, OTE, etc)

[balerjoe 0]

What do you mean? This is just a SIMPLE overview of a project Ron wanted me to do. All the controls will be discussed later. Thats where you along w/the pros on heres help will come in.

[Guest]

OK ... now we’ve got something to work with ... just remember, to play this game effectively, you’re not writing to us on the forum ... you’re an engineer (integrator) who’s trying to sell his services to a prospective customer ... with that in mind, I think that the document below is a little bit more along the lines of what you need ... just remember that I personally don’t know diddly about milk processing ... all I’m trying to do below is suggest a format and a tone ... IMPORTANT! ... the document below is what I would consider a very rough draft ... I would put a lot more work and thought into this before it landed on a customer’s desk ... remember ... while you’re writing your proposal, other firms are doing exactly the same thing ... MAYBE the customer will cut you some slack for misspelled words, poor grammar, inconsistent punctuation, etc. ... but maybe not ... maybe the person who’s going to have the final say-so on whether or not you get this job is a neat-freak ... a bean-counter who has no other way to judge your ability to do this integration job successfully than by your willingness to spend the time and energy it takes to write a first-class proposal ... let’s assume (gosh I hate that word) that those other machines are “beyond the scope of this project” as the official wording goes ... skip them for now ... we’ve got plenty to start on with what you’ve already outlined ... and yes, you’re on the right path ... but I think that by now you realize that you still have a long way to go ... but heck, if it were easy, then everybody would be doing it ... and yes, you DO need a drawing ... the customer will expect one ... so do we ... next step ... get started on a drawing ... post whatever you come up with ... AND - very important! ... go back through the proposal that I included ... it is NOT ready to go ... see if you can spot the items that I left “unfinished” ... correct me where I made incorrect assumptions ... work on it some more (until it looks “loved”) and then repost it ... I’ve attached my original document below for your convenience ... basic idea: if you expect the customer to pay out his hard-earned money for this rig, then you need to give him all of the details that he needs in order to make an informed decision about whether or not your solution is the best one ... or maybe he’ll like your competitor’s proposal just a little bit better? ... somewhere along the line you’ll realize just how important all of those “required” English lessons are when you’re trying to nail down a college degree ... they are often the one-and-only difference between success and failure when you’re trying to solicit business from some fat-cat manager in the front office ... point for today: programming a PLC is the easy part of all of this ... think: the guy (or gal) who can successfully do all of this “project management/proposal writing/process design/machinery engineering/customer relations/salesmanship” type stuff is probably quite capable of picking up on how to write a ladder logic program ... that might help explain why you see so many job offers for these types of skills - and not that many for a pure “PLC programmer” position ... I’ve got a hunch that the people who do all of this dreary “up front” work typically save writing the PLC program for dessert ... it’s basically the fun-and-games reward for the end of a long, hard-fought battle ... milk_machine_2.doc Edited 30 Dec 2005 by Ron Beaufort

[Guest]

actually all I want is for you to be happy ... you asked for advice ... I gave you the best advice that I could ... this project is EXACTLY what I’d do - if I were in your situation and had the same objectives that you posted earlier ... a couple of other guys have already posted their opinions that this is a sensible path to take ... it will cost you little or nothing (except time and effort) ... I say let’s see where it leads ... but ... if you want to just skip ahead to the PLC programming part of the job, feel free ... we can always come back and do the integration part later - if you so desire ... just type up a list of I/O points and tell us what happens first - and second - and so on to make the machine work ... we can start programming from there ... write up some rungs .... post some code ... we can do whatever you want - in the order you want ... Edited 30 Dec 2005 by Ron Beaufort

[TConnolly 13]

I have found from time to time that a Piping and Instrumentation Drawing is useful. Some engineers swear by them. Others loath them. I regard them as a tool, to be used at times and left in the tool box at other times. Your description sounds like something for which a P&ID will be a useful tool. At first I wouldn't get too wrapped up in making the P&ID conform exactly to ISA standards, you'll tweak and refine it as you progress. This power point presentation has some good introductory info on P&IDs beginning on slide 38. http://lamspeople.epfl.ch/kirrmann/Slides/...rumentation.PPT Here are some examples: http://www.jensensystems.com/hardware1.htm http://www.sentry-equip.com/pid.php http://lamspeople.epfl.ch/kirrmann/Slides/...NID_Symbols.tif http://www.pip.org/downloads/Sample-PID.pdf Don't let it overwhelm you. Its a tool for breaking the process down into discrete manageable chunks. Start with a representation of one of the membrane vessels. Show the process flow into and out of the vessel and draw the components (pumps, valves, flow meters, pressure sensors) that control the process flow. Then attempt to add the next step in the process. Use simple symbols, blocks, lines, and circles. The intent at this point is to convey function, not the specific device that performs the function. Don't try and show every single thing and don't make the drawing too "busy." This is an example of a drawing that is too "busy" for a beginner: http://lamspeople.epfl.ch/kirrmann/Slides/...NID_Example.tif Go ahead and take a look to get some ideas, but don't try to emulate something like this at this point. Remember that this is only a tool for breaking the process down into something that you can manage.

[TimWilborne 108]

Ok I understand whats going on now. I just thought if this was the beginning of class on Plcs I would have been blown away from the start. This sounds really interesting

[TimWilborne 108]

Just a few questions about this project and tell me if I am ahead of the game, behind or way out in left field. What is the physical size of something like this? Would it be something you would hardwire, just network the I/O, or would you also look at networking the motors, etc? Is there going to be diagnostics of the process? The purchaser always likes the graphics of gauges, output, etc on the Panelview while the machine is running. But I see many people leave out diagnostics on how to figure out what is wrong with the machine which is something maintenance loves. Maintenance can make you or break you on getting future projects from the same company. Is there going to data logging to the processing facilities network? How detrimental will it be if part of the process breaks? Do there need to be secondary’s on the chillers, water heaters, etc. Will they have to sanitize the whole thing if it is down for too long? Does this mean the temperature sensors will have to sense both liquid and steam? It makes a difference on what type of temperature sensor you spec.

[balerjoe 0]

Heres a more accurate description. Nice format I'll keep this in mind. We will not be looking at steam temps & water. Just water These project could easily turn to be alot more than what I am trying to do. Will see as this moves forward how far I can go with it. I'm keeping that out of the scope of this project. PROPOSAL FOR A SINGLE-PASS REVERSE OSMOSIS (RO) MILK PROCESSING MACHINE Process Overview Milk will be brought from a silo to a balance tank. Then pumped into the machine using a 3 stage centrifical pump 50hp motor. This machine will process raw milk received by truck from the dairy and extract water from it resulting in a finished product which can be transported in high concentration. The machine will produce 80 gpm of concentrated milk product. Process Outline The machine will consist of 48 membrane vessels. Each vessel will contain 4 interconnected membranes. Maintaining a proper setpoint ratio will require a minimum differential pressure of 400-600 psi across each membrane. This pressure will be provided by a 10 hp motor and a centrifical pump for each vessel. A VFD (Variable Frequency Drive) will be used to control the speed of each motor. Throttling valves will be provided on the back of each vessel. There will be 4 stages of vessels with 2 vessels per stage. Each stage having 6 pumps & motors. Milk tempature will maintain 43 degrees F. Not exceeding 45 degrees F and will not drop below 37 degrees F. Each membrane vessel will be equipped with a cold water jacket. These jackets will be controlled by proportional valves which will regulate the flow of cold water. In the colder months milk will run through a shell & tube heat exchanger. This will ensure regardless of the season the machine can run in spec. Provisions for Clean In Place (CIP) Operations Hot water will be routed to all vessels for the CIP (Clean In Place) process. This will be supplied by the balance tank. Proper chemical mixture will be done by hand. The hot water requirements will be 88 gpm with a temperature range of 140 to 160 degrees F. A balance tank will be used to ensure that no air enters the process. System Control This process will be controlled by an Allen-Bradley PLC-5/20E processor. The program will be written using commonly accepted practices of ladder logic programming. Each instruction and rung will be documented with meaningful comments to ensure ease of troubleshooting and maintenance of the system. Operator’s Interface The machine will be provided with an Allen-Bradley PanelView terminal to allow for the equipment operator to monitor and control the system. Output Storage Storage and handling of the finished product is beyond the scope of this proposal. Handling of Poor Quality Product Poor quality product will be defined as product which does not have the proper ratios of protein to fat. Any poor quality product will be diverted to a wastewater drain. Other Required Facility Services The electrical service will be 3-phase 480 VAC. Compressed air will be required for the air actuated valves. Cold water will be a mixture of 70% water 30% gycol. Edited 30 Dec 2005 by balerjoe

[Gerry 13]

I don't want to be a party-pooper, but I think chosing a RO plant as a beginner's learning project is overly ambitious. How about something smaller and more easily understood? My suggestion would be a single pasteuriser unit: balance tanks, heat exchanger, separator. Just tackle the process initially, the CIP can be considered later. I think you must have working examples of the above somewhere in your factory - sketch the process schematic, write a functional description of how the process has to function, list all the control elements (valves, pumps, sensors,etc.), then contemplate how to make the PLC achieve the desired result. For any that are unfamiliar with dairy factories, the above contains a number of common elements that most people can comment on: star-delta starting (separator) temperature control on-off valves It also requires start-up, production, and shut-down procedures in addition to CIP procedures. Edited 30 Dec 2005 by Gerry

[balerjoe 0]

Good point I'll keep the CIP process out of this. Let me work on the P&ID list so I can get the programming end of things. I'll finish the drawing later. But I think from what was explained we have a general idea of how things work.

[Lancie1 0]

Your proposal is getting better, but there are a few language and syntax errors. For example, see the suggested changes in RED . I know that spelling and grammar are not usually considered part of a programmer's job, but Ron's proposal made them part of this one. There seems to be conflicting information about how many 10 HP pumps you have. One place you say there are 48 vessels with one pump per vessel (=48 pumps, 800 Amps required), another place you say there are 4 stages with 6 pumps per stage (= 24 pumps, 400 Amps total required). An accurate process description is a required first step for writing an accurate program! Edited 1 Jan 2006 by Lancie1

[gravitar 3]

Wow, this is a great thread! Proposal writing is something I have done very little of over the last several years, being an in-house programmer/electrician/maint. supervisor! It is also interesting to see the "inside" of a process that is far removed from the typical auto industry fare that I'm used to. I have to chime in and reinforce the fact that grammar, punctuation, and mechanics are VERY important for something like this. Many educated people will see this proposal and chances are they won't have anything to judge you upon other than the quality of this document. To be blunt, if you don't demonstrate a good command of the English language, you won't appear intelligent. Same goes for the spoken language when you meet with your prospective customer.. Until you've developed a good rapport with them, you had better be speaking the King's English! (as my old boss used to say :) I'm thinking a basic process flow diagram should accompany this proposal.. And I suppose it is too early for a BOM but I would think the "highlights" should be listed as well. (5/20E is a start.. how about size of panel, make/model of VFDs, make/model of motors, other major components that you will purchase, etc)

[balerjoe 0]

What needs to take place with the vessels is there will be two vessels per pump/motor. I'll explain more & why this is neccesary later. Thanks for the recommendations I'll do what I can to improve.

[Gerry 13]

I still think this is way too complex and multi-disciplined to be used for learning how to prepare a Control project. First off, balerjoe is describing an ultra-filtration plant - not a machine. It will require a building (civil engineering), stainless steel design and fabrication (mechanical engineering), process design ( chemical?? engineering), sizing of pipes, valves, and pumps (more mech. eng.). This thread could go on for a very long time before getting to any detail of what a PLC is required to do with it all.

[TimWilborne 108]

I don't think it is too complex. I say keep it like it is and see where it goes. Lets say the building is already built. Between all of us we can spec and design the pumps, valves, mechanical, etc. And somethings you can just say got done. I think this is great so far, the proposal has always been my week spot. And while you may not need to know about mechanical, fluid power, etc, you should be familiar enough with it that you can work with the people doing it

[balerjoe 0]

Heres my first of many flow charts. flowchart.doc

[TimWilborne 108]

At which point in the process will the poor quality product be routed down the waste water drain Or is that the Milk Water Silo Edited 2 Jan 2006 by TWControls

[balerjoe 0]

The only time that will be happen is when one thing is allowed to happen. If milk gets above 45 degrees F other than that lets assume it will be fine. I forgot to mention this machine will not pasteurise the milk. That will be a seperate process. Edited 2 Jan 2006 by balerjoe

[balerjoe 0]

How about a pilot unit? It can just have 8 membrane vessels, a balance tank,shell & tube exchanger. This sounds a little easier. Lets shoot for this to simplify everything.

[Guest]

Greetings to all, well, Joe ... it looks like your project is moving along ... as of this writing you have at least six (including myself) interested members offering help and advice ... consulting my crystal ball, I’m looking about three or four weeks into the future ... I see a neatly labeled loose leaf binder which contains the final outcome of this project ... there’s a full a one-inch margin all the way around each page ... the binder is complete with labeled section dividers ... the sections include: 1. the proposal ... 2. overview drawings of the process ... 3. BOM (Bill of Materials) for all parts ... 4. electrical schematics ... 5. a detailed P&ID ... 6. a full PLC I/O list ... 7. PLC ladder logic program listing ... 8. full documentation on DIP switch settings, jumper positions, and all of the other assorted (but incredibly important) things that don’t show up in the PLC program file ... 9. screen shots of the operator’s HMI device ... 10. and other things which I’m sure we’ll come across as you proceed ... (personally, I look forward to seeing the suggestions that others are bound to make along these lines) ... oh ... and very important! ... the binder should (must?) contain a personal resume of all of the people who will be involved in completing the project ... in other words, you-yourself-alone ... so knock together a resume ... if you don’t want to use real names for some reason, then make up something glamorous ... but post the results so that we can help you iron out the rough spots (if any) or complement you generously on a job well done ... about the resume ... done correctly, this can be a very helpful exercise in-and-of-itself ... basic idea: do TWO resumes ... the first one should reflect where you stand today ... try to be impressive - but be honest ... don’t put down anything that you can’t back up with references, or with examples, or with demonstrated performance ... for the second resume, put down everything that you WANT to be able to say about yourself one year, or two years, or more years down the road ... then once you’ve got both resumes done, start asking yourself “Now what steps do I have to take in order to get from HERE (resume #1) to THERE (resume #2)?” ... once you’ve started nailing down the answers to that particular question, then you’ll have a very good idea of how to lay out a “game-plan” to reach your personal goals ... why not post both resumes? ... do that and we’ll try to help you chart your pathway ... looking down the road, here are just two quick scenarios to consider ... nothing here is engraved in stone, of course ... just some ideas to think about ... suppose that you decide to go to work for an integrator ... you submit an application for employment ... you get called in for a personal interview ... you take your nifty neat little project binder with you ... you show this to your prospective boss ... do you think that he will be favorably impressed with what you’re showing him? ... yes-or-no? ... after all, you’ve done ALL of the work on this project yourself ... sure, a few more-experienced guys on the forum gave you a little bit of advice from time to time just to keep you on track, but they didn’t do the work ... you did ... smart money says that the guy interviewing you will like what he sees in that binder ... basically it shows that you’re familiar with all of the skills that his company requires for this position ... no, it’s not quite “real-world-hands-on-down-in-the-trenches” experience ... but it’s a LOT better than nothing ... maybe enough to get a foot in the door ... now let’s suppose that things are a little bit different ... instead of trying out for an integrator’s job, you decide to go back to school ... full-time or part-time ... whatever ... but either way, you’ve decided that some formal education will be necessary before you can meet all of those goals that you set for yourself back in “Resume #2” ... now when you’re taking those classes do you think that having done this little project “up front” just might help you along the way? ... yes-or-no? ... if nothing else, this project should at least show you where you need to concentrate your efforts ... my point: sometimes it’s important to know what you DON’T know ... this little project should help you recognize the skills that you’ll need on the job ... and to recognize which schools are capable of teaching you those skills ... and also, to recognize which schools are mostly a waste of time - and money ... moving right along ... I’m inclined to agree with my distinguished colleague Gerry that this project seems to be quite sophisticated for our purposes ... at the same time, I like the suggestion of TWControls (also distinguished) that we continue along and see where it will go ... personally, I’d like to do that ... but ... I think that the time issue is going to murder us if we stay on this same track all the way through ... still you’re the boss, Joe ... it’s up to you to choose the project ... we’re just along for the ride ... and so I like your latest post: sounds great ... just rewrite the proposal and we’re ready to continue ... BUT ... may I ask what program you’re using to type all of this stuff up? ... if it’s Microsoft Word, then why aren’t you using the spell checker? ... there is no valid excuse for misspelling things such as centrifical, tempature, and gycol ... the spell checker should light up like a Christmas tree on these ... also ... don’t abbreviate “temp” for “temperature” ... or “spec” for “specification” ... on the other hand, commonly used abbreviations such as gpm and psi are generally ok in a technical document of this nature ... and I notice that you spelled “centrifugal” correctly in your flow chart ... what happened to the spelling in the proposal? ... finally ... Alaric was very helpful in giving you those P&ID links ... when can we expect to see something along those lines? ... the flow chart that you posted is a step in the right direction ... but a P&ID would be much more professional ... and more in keeping with this type of project ... and talk about helpful! ... I notice that Lancie1 even took the time and trouble to mark up your proposal IN RED ... as for me, my typing time is going to be a lot more limited as soon as the holidays are over ... yes, I do have a bo$$ ... but I'll still do what I can from time to time to help you along ... and here's a tip to keep the professionals interested in your thread ... POST EVERYTHING! ... it's a lot easier (and more entertaining) for them to correct your mistakes than to tell you how to do things ... and you'll learn a lot more that way too ... Edited 2 Jan 2006 by Ron Beaufort

[TimWilborne 108]

Or if you are worried about the time it is going to take to get to the details or that some here will get bored with some phases of this, may be this topic should be broken into multiple topics. That way people can be involed in the part of the process they wish too. From Rons last post with a few comments 1. the proposal I would like to go further into the details such as the resume. I personally had never thought of putting a resume in with my proposals 2. overview drawings of the process The basics you must think about. Not only the electrical controls but an overview of pneumatics, hydraulics, mechanical, etc. A lot of control guys don't want to look at these but atleast having a general idea of what is going on with these can keep you from making mistakes down the line. 3. BOM (Bill of Materials) for all parts So many things are missed here. From wire duct to screws to fuse holders to...... 4. electrical schematics This should be its only topic definately. It has been posted many times and there are so many different ways to do it and so many different software packages 5. a detailed P&ID Very important and usually left out. You end up to scrambling around trying to engineer this on the fly and it looks terrible. 6. a full PLC I/O list Pretty simple but spares are usually left out 7. PLC ladder logic program listing Planning before you write the program makes it much easier to read later when you are making a service call and the program is not fresh on your head. And even though every programmer has a different method for programming, having a good general layout that you can use for all your programs is very helpful. Not only for you but for companies that you sell multiple machines too. Once they understand one of your programs, they will not have too much trouble following the rest of your machines programs 8. full documentation on DIP switch settings, jumper positions, and all of the other assorted (but incredibly important) things that don’t show up in the PLC program Hardly ever done but goes back to good maintainence tools helping sell future projects 9. screen shots of the operator’s HMI device Even simple HMI programs should have this. I have a Flash Welder that was installed before I started working here that we have been having some trouble with. Everyone knows how to operate it, but it also have all types of graphs that help you determine what is wrong with it. Not a single person knows how to read them. 10. and other things which I’m sure we’ll come across as you proceed And I bet there will be many

[balerjoe 0]

Heres the final proposal. I'll work on the rest of this when I get alittle time. Sorry for the spelling errors I was in a hurry. PROPOSAL_FOR_A_SINGLE.doc

[TimWilborne 108]

Although this is not real, I would watch using statements like this. I would specify the what type of cooling properties it should have and what temperture range it should operate in. If you provide the chiller system, you may want to provide some lubrication specifications for the additive. This makes them have to make sure the water is to your specification but leaves the actual spec up to them. This way EPA and Department of Agriculture problems are theirs fully. It probably will never happen to you but I have heard of it. A company told a customer what type of additive to put in there water. A line busted and a couple hundred gallons leaked onto the ground. A disgruntled employee called the EPA. The EPA then determined that it had polluted the soil and the customer told them that the company had specified it. The EPA came after the company that installed the equipment

[vinod.mojar 0]

Hello to all, First let me introduce myself to you people. I had work on similiar project in milk industries. It includes UF, NF, RO & MB units. I just gone through your folw chart. in this you mention that raw milk first pass through the prefilter. Can you explaion it more clearly that what type type of Perfilter you are using? and also for what? means to seperats Proteins, facts, Lactose or salts. Beause the plant where i am working it consists first UF, second NF & then NF. In each stage pressure requirement goes on increasing. means in UF we need less pressure as 1 to 2 bar. But in NF it goes to 20 Bar And at last at RO it goes to 30 bar. The advantage of it that you can save your energy & increase your membrane life.