Addressing the elephant in the corrugated plant
Understanding the Starch System in Your Corrugated Plant
The starch system in a corrugated plant could easily be compared to the brain in a human body. The body cannot function without it and yet very few people seem to have a comprehensive understanding of how it functions. They can tell you what purpose it serves and know immediately when it is not working properly, but they can be fuzzy on the details of how it all fits together.
“How important is that starch formula? Why does it even matter? We just need better resin. Do we really have to clean that thing again? Why are the lines clogged? Why can’t we just run it like we did at my old plant? What is the point of all these alarms that we keep silencing?. Starch is starch, why does any of this matter?” These are just a few of the seemingly endless questions that I hear bandied about in plants I’m working in when the subject of the starch system comes up in conversation. I will admit that I’m no expert myself, having only been working in and around them for 3 years, so when I get asked a question I do not know the answer to, I turn to an expert I trust. Mike Kircher is a Senior Technical Sales Manager for Henkel Corporation (formerly National Starch in the US) and he has held that role for almost 18 years. Prior to that, Mike worked in corrugated plants for 32 years, holding positions from operator all the way up to plant manager. He is my go-to expert when it comes to all things starch.
I asked Mike what he thought was the most common misconception surrounding the starch system in today’s corrugated plants and his answer surprised me. “Modern mixers. No one utilizes the technical advantages of modern mixers. They spend all this money on a new mixer and still run it like they did the mixers 25 years ago. They don’t know or understand all the features on the new mixer so they don’t use them. The opportunity to utilize better formulation techniques is often ignored due to this misunderstanding of the equipment, so they default to running it the only way they know how”
Technology is only as useful as our understanding of how to use it. That is something we all have probably realized as we’ve struggled with a starch mixer control panel or a new update on our smartphone. That is another reason why it is so important for plants to have good suppliers, with technical support in the field, standing in their corner. What is the point of spending the money on an upgrade, if we cannot take advantage of it? Vendors have to take the time to train their customers, from operator up to superintendent, on how their product functions and why they have selected the starch formulation they have implemented. If, as a plant, your vendors are not offering you that support, then demand it (politely of course). Your corrugator is dependent on your starch system running efficiently and you need knowledgeable operators to make sure your organization is getting the maximum benefit from your equipment investment.
Combine good vendor field support with hands-on experience, and you are on the right track; the veil of mystery around the starch system suddenly starts to lift. It is that experience that teaches you that every starch system is unique. Each plant and operation is unique, regardless if it is an integrated or independent operation. Those unique characteristics need to be considered when making starch formulations. Spend a lot of time cleaning starch lines and you will begin to realize that PVC pipe tends to be easier to keep clean than stainless steel starch lines. Experience taught Mike that the simplest thing a plant can do to make their starch run better is to “not carry more starch than you need. The faster you can get from batch completion to flute tip, the better”. After all, starch is organic and can “go bad” which is the easy way to say its bonding properties decline with time. You can think of it like buying a 12 pack of beer at the store and bringing it home. Opening all 12 beers and sitting them on your counter for later when you only plan to drink one would not make for very good beer drinking. Your starch is the same way. Only take out what you plan to use right now.
I asked Mike, what would he change around starch system protocols typical in the corrugated industry if he had a magic wand to make it happen? He said he would get plants to “stop using cookie cutter formulas. Formula optimization is necessary to achieve your best bonding potential. Consider the board grades you run… Find the sweet spot for your individual plant”.
Misunderstanding of the starch bonding and batch process fuel the confusion surrounding starch systems. I can think of no greater example than a plant experiencing clogged starch lines. Cut open a clogged starch line and time how long it takes until a particular type of resin is blamed. I assure you it will not be long. Are resins really all to blame for the build up inside of starch lines? As Mike explained to me, “Resins and additives are blamed because when you cut open a clogged starch line it has red in it. In reality, that red color is the dye that is in the starch. Certainly resin can build up, but the majority of it is the starch itself and the resin gets a bad rap because of that red color you see… factors like water hardness can exacerbate the buildup. If resin was the ultimate reason for buildup, then the line from the resin tank to the mixer would be solid because it is in contact with 100% resin all of the time… typical patterns of poor system cleaning protocols compound the issue”.
A multifaceted problem lends itself to a multifaceted solution. Let’s face it, nobody knows what the inside of their starch line looks like unless they take it apart or stick a camera in it. Indicators like the inability to supply enough starch to keep your pans full, taking a long time to pump a batch over, or having to slow down your run speed take some of the guesswork out of what your starch lines look like. They are probably restricted. Starch flow problems can really mess things up for a corrugator. If you are waiting for flow restriction indicators to tell you that your system is dirty, you will probably need to prepare yourself for some unplanned downtime or having to adjust your run schedule. Maintaining a clean starch system is crucial to an efficient operation for your whole corrugator. “Starch is like paint. The sooner you can clean the paint brush with water, the better. Try to develop a sense of urgency with the timing of your cleanings… Don’t let things dry out”. Pay now or pay later, was the impression Mike gave me when it came to system cleanliness. There is no magic in maintaining a clean starch system. Time has to be dedicated to cleaning up. Regular water washes can help maintain your lines, but they do not remove starch build up and the timing factor of those washes is critical.
I get it. You are a 24/7 plant. You ran production all weekend. You hardly had time to sit down and respond to emails let alone find time to run water through your starch lines or do a good cleaning. That is where a good cleaning product can be a big help. There are several products on the market such as Walla Walla that work to fight bacteria and reduce gelatinized starch build up or Evolution Starch Off that uses active enzymes to break down dried starch from inside starch lines.
I can hear some of you already questioning the use of line cleaners. But how do I know if any of those cleaning products actually work? I asked Mike the same question. “Are you getting starch showing up in your pan after you use it in your lines? If the answer is no, then the product you’re using doesn’t work. Put the cleaner in a pan and see if it removes buildup inside of the glue roll cells. Grab a microscope camera and take before and after pictures of the cells. There should be a visual difference between them. Has your flow rate improved?”
Finding the right formulation for your unique operation may require calling in some help. Consider getting your supplier involved in the training of your operators who deal with your starch system. Seek out the root cause of line clogs and implement a consistent cleaning procedure to prevent them in the future. Take it from me, ask someone with more experience when you want to learn more. As we all work to better understand that starch system in our plants and capitalize on its full potential, we can clear some of the fog surrounding the most important system attached to the corrugator. After all, we can’t make board without starch.