Machine stability through “charge” management, and why starch consistency matters
“The modern paper mill uses large amounts of energy, water, and wood pulp in a highly efficient and extremely complex series of processes, using modern and sophisticated controls technology to produce a sheet of paper that can be used in incredibly diverse ways.” — Paper mill, From Wikipedia, the free encyclopedia.
I could not find the citation, but I have even read somewhere that papermaking is the most complicated of all manufacturing processes. Just think about the number of variables in the total system.
Earlier this year I wrote two short compositions about the importance of maintaining consistent starch solids and the costs associated with failing to do so. This piece proposes to combine the points of the first two pieces into a practical way to maximize benefits and minimize costs with regard to starch use, generally, and wet end cationic starches in particular.
While obviously not always so, it sometimes seems that chemistry is often viewed as a binary event rather than a process. Unlike machine components that normally either work or don’t work, are on or off, chemistry has to be managed, optimized and controlled.
In the second composition (STARCH CONSISTENCY: Part 2) I observed that “due to volume and charge density, cationic wet end starch is typically (though not always) the largest cationic influence on system charge as the pulp slurry approaches the headbox;” thus, the reason why control of starch consistency is so important.
Recently I tweeted (@starchguy) one of my favorite quotes: “Perfection is not attainable, but if we chase perfection we can catch excellence.” (The quote turns out to be from Vince Lombardi, which I did not know.) My argument is simply this: in order to maintain stability, optimize costs, runnability, and tests, we must control, particularly, those components having the most impact on the process.
The means now exist and are well enough understood (PCDs, Zeta meters, etc.) to monitor and control this important property, i.e. charge. By using such instruments to regularly monitor the paper machine at consistent, regular intervals (hourly, bi-hourly until the system is understood), we can observe, monitor and learn to control the paper machine’s response to chemical inputs (starch, et.al.) to achieve optimum properties, consistent runnability and lower costs.
Operational excellence can be achieved for most grades, most of the time The simpler the additive system, the less complicated it is to control. Contact Starch Performance Services to discuss the potential savings available in your paper making system.