ignore-rant
Member
Hello engineers/technicians of PLCS.net! I require your assistance, if you may be so kind to provide it. I hope this is an appropriate query to make to you fine folks! Okay, so my first post is going to be a long winded one..
I am taking on projects from my graduating University as a way to refresh myself on control technologies and to build up my portfolio in hopes of making myself a more lucrative prospect for possible employers.
One of the projects I have conceptualized is a physical, simulated batch process. Here’s a run-down of my project idea:
The batch process is a simple mixing station. The tanks/vessels/containers I plan to use range from 5-15 gal. I want to make my system compact enough to cart around (for demonstration purposes).
I have 3 ingredients: continuously circulated supply of WATER, finite supply of RED DYE, and finite supply of BLUE DYE.
I can create 3 products – RED product (water and red dye mixture), BLUE product (water and blue dye mixture), and PURPLE product (water, red and blue dye of equal parts mixture).
When I select the product and the amount of product (through my HMI) I want to create, the ingredients are sent to a mixing vessel. The ingredients are mixed and I get my finished product. The finished product is then sent to a product recycling tank so I can remove the dye. To remove the dye from the water/dye solution, I’ll be using a chlorine/bleach solution. Why? Because of the dye’s I am using:
http://brightdyes.com/FAQ.html#10 (A tracer dye that is strong visually and relatively cheap)
From the FAQ, it states a chlorine/bleach product should successfully remove the dye concentration and eliminate any color from the water/dye solution. I then take the chlorine/water solution and use a water filter (not sure what type of filter to use) to remove the chlorine from the water. The filtered water is then pumped back into my water tank.
This process continues until there is no more dye ingredient(s) or chlorine left.
To control this process I am using a Siemens S7 PLC/IPC. I am quite comfortable with the programming side of things and feel I can accomplish this. Design/feasibility of overall process is an issue.
http://www.automation.siemens.com/m.../en/industrial-pc/Panel_PC/Pages/Default.aspx (Link to the IPC I plan to mount to my system)
I have a link to the sample P&ID I scratched up on my notebook to give you an idea of the process I had in mind:
http://i.imgur.com/4yVYOei.jpg
Sorry if the sketch is a poor attempt at a P&ID. Just brainstorming.
My problems/concerns:
1. I plan to use 6 solenoid valves to control the step-by-step process of my system. Is this the best way to do so? Everything from adding of the ingredients to mixing and recycling will be controlled by the solenoid valves. I will have ultrasonic level sensors (suggestions on a better sensor?) to measure the ingredient tank levels and I will have to create an algorithm to calculate how much of each ingredient is to be added to the mixing vessel based on operator input. So again, is this the best method to go about doing that?
Small note: The thought is using solenoid valves will be the best method of controlling the input to the mixing vessel because my ingredients would be gravity fed. I was thinking there would be no need for small DC motors to be used. The ultrasonic sensors are being used because they are the ones available to me currently in the lab. Please educate me if I am going about this completely wrong.
2. I believe chlorine is the best way of removing the dye from my product. I hope there will be no toxic byproduct, such as gasses, from mixing the chlorine with the water/dye. The dye manufacturer says their product is non-toxic, so no ill effect should come of the mixture, right? RIGHT?! The system I want to create will in a lab setting with no other harmful chemicals around, but the chlorine will be in an enclosed container. Will the chlorine pose any health hazards?
3. The water filter. I'm a bit hazy on what route to take when removing the chlorine. I've done Google searches and saw recommendations of using an acid, such as citric products to neutralize the base or of reducing the pH. But, I don’t want to introduce contaminants into my water supply. I’m not sure what the best type of water filter to use is. I suppose a simple home filtration system should suffice? The costs, though, I've seen are a bit exorbitant.
I've seen recommendations of using activated carbon or ion exchange resins to see if they can remove the dye. I have samples of the dye on its way so I can perform some tests and see if this is a better solution! I can then create my own simple filter.4. Lastly, does this project seem like a worthwhile venture? I wanted to create a system that was very sleek in design. I plan to use clear containers/tanks so people could view the process as it takes place. I am going to use a touch-screen HMI that allows for simple operability and intuitive to any user. I want to create a model that can be improved by future project teams and can be presented/demonstrated in the classroom and for visitors alike. Before this project can be accepted at the department’s expense, I need to make sure I have a solid proposal. Help a brother out?
Please throw whatever advice/criticism my way. If you need more information, let me know! I plan to document my project and use it to build up my portolfthe time I complete this project.
TL;DR I want to create a physical batch process. I have some technical issues I need addressed.. I'm not a smart man.
I am taking on projects from my graduating University as a way to refresh myself on control technologies and to build up my portfolio in hopes of making myself a more lucrative prospect for possible employers.
One of the projects I have conceptualized is a physical, simulated batch process. Here’s a run-down of my project idea:
The batch process is a simple mixing station. The tanks/vessels/containers I plan to use range from 5-15 gal. I want to make my system compact enough to cart around (for demonstration purposes).
I have 3 ingredients: continuously circulated supply of WATER, finite supply of RED DYE, and finite supply of BLUE DYE.
I can create 3 products – RED product (water and red dye mixture), BLUE product (water and blue dye mixture), and PURPLE product (water, red and blue dye of equal parts mixture).
When I select the product and the amount of product (through my HMI) I want to create, the ingredients are sent to a mixing vessel. The ingredients are mixed and I get my finished product. The finished product is then sent to a product recycling tank so I can remove the dye. To remove the dye from the water/dye solution, I’ll be using a chlorine/bleach solution. Why? Because of the dye’s I am using:
http://brightdyes.com/FAQ.html#10 (A tracer dye that is strong visually and relatively cheap)
From the FAQ, it states a chlorine/bleach product should successfully remove the dye concentration and eliminate any color from the water/dye solution. I then take the chlorine/water solution and use a water filter (not sure what type of filter to use) to remove the chlorine from the water. The filtered water is then pumped back into my water tank.
This process continues until there is no more dye ingredient(s) or chlorine left.
To control this process I am using a Siemens S7 PLC/IPC. I am quite comfortable with the programming side of things and feel I can accomplish this. Design/feasibility of overall process is an issue.
http://www.automation.siemens.com/m.../en/industrial-pc/Panel_PC/Pages/Default.aspx (Link to the IPC I plan to mount to my system)
I have a link to the sample P&ID I scratched up on my notebook to give you an idea of the process I had in mind:
http://i.imgur.com/4yVYOei.jpg
Sorry if the sketch is a poor attempt at a P&ID. Just brainstorming.
My problems/concerns:
1. I plan to use 6 solenoid valves to control the step-by-step process of my system. Is this the best way to do so? Everything from adding of the ingredients to mixing and recycling will be controlled by the solenoid valves. I will have ultrasonic level sensors (suggestions on a better sensor?) to measure the ingredient tank levels and I will have to create an algorithm to calculate how much of each ingredient is to be added to the mixing vessel based on operator input. So again, is this the best method to go about doing that?
Small note: The thought is using solenoid valves will be the best method of controlling the input to the mixing vessel because my ingredients would be gravity fed. I was thinking there would be no need for small DC motors to be used. The ultrasonic sensors are being used because they are the ones available to me currently in the lab. Please educate me if I am going about this completely wrong.
2. I believe chlorine is the best way of removing the dye from my product. I hope there will be no toxic byproduct, such as gasses, from mixing the chlorine with the water/dye. The dye manufacturer says their product is non-toxic, so no ill effect should come of the mixture, right? RIGHT?! The system I want to create will in a lab setting with no other harmful chemicals around, but the chlorine will be in an enclosed container. Will the chlorine pose any health hazards?
3. The water filter. I'm a bit hazy on what route to take when removing the chlorine. I've done Google searches and saw recommendations of using an acid, such as citric products to neutralize the base or of reducing the pH. But, I don’t want to introduce contaminants into my water supply. I’m not sure what the best type of water filter to use is. I suppose a simple home filtration system should suffice? The costs, though, I've seen are a bit exorbitant.
I've seen recommendations of using activated carbon or ion exchange resins to see if they can remove the dye. I have samples of the dye on its way so I can perform some tests and see if this is a better solution! I can then create my own simple filter.4. Lastly, does this project seem like a worthwhile venture? I wanted to create a system that was very sleek in design. I plan to use clear containers/tanks so people could view the process as it takes place. I am going to use a touch-screen HMI that allows for simple operability and intuitive to any user. I want to create a model that can be improved by future project teams and can be presented/demonstrated in the classroom and for visitors alike. Before this project can be accepted at the department’s expense, I need to make sure I have a solid proposal. Help a brother out?
Please throw whatever advice/criticism my way. If you need more information, let me know! I plan to document my project and use it to build up my portolfthe time I complete this project.
TL;DR I want to create a physical batch process. I have some technical issues I need addressed.. I'm not a smart man.