The author has published many articles on building nanochemistry wet end processes. This piece over-views correcting three major errors by making nanochemistry modification to the existing process. We can do this for you.

Unfortunately, the adoption of wet end chemistry in mid 20th century was abrupt. Suppliers with success in the chemical pre-treatment of potable water offered their bag of tricks to paper mill superintendents, who gave it a try, often with improved results in retention and drainage.

The die was cast, and paper is unique amongst global industries to fully entrust a critical operational role to an independent party with directly conflicting interests. The resultant embedded inefficiencies are removable.

Mixing

The industry fails to mix chemicals and stock with water to homogeneity.

An enterprising Finnish Company, Wet End Technologies, introduced the TrumpJet booster pump in 2003. It has shipped about 300 units and reasonably claims to reduce chemical usage by 20-50%. www.wetend.com

This contrasts with the author’s nanochemistry data which shows a reduction of 90-99% in chemical usage. The difference is that in nanochemistry we use sophisticated technology which reduces chemical bundles to molecules.

Electrostatic Charge Neutralization

Colloidal particles typically carry an electrostatic charge, or zeta potential, measured in millivolts. The particulate zeta potential has a critically important influence on the stability of the colloid. In papermaking we must neutralize that opposing charges so that the final zeta potential is zero.

To the extent we fail to do this, both physical properties and process performance are impaired. When we consistently attain a final net charge of zero zeta potential, both are maximized.

Counter-Productive Agitation

When we mix to homogeneity and neutralize the repulsive charge, van der Waals’ Force asserts itself to bring all the colloidal particles together. The Force exerts itself with a power that increases exponentially, inversely with inter-particulate distance.

Because the modern paper machine does NOT mix to homogeneity on the wet end, the effort is pursued in the headbox and by shaking the wire. This works against van der Waals Force and is counter-productive to nanochemistry. http://www.papermaking-chemistry.com/max_waals_force.ppt

What is needed after the particles are mixed to homogeneity and charge-neutralized is quiescence so that the naturally attractive Force can bring them together. At this juncture, the less agitation the better!

Mea Culpa

If you were paying close attention to page 10 of the exhibit, it purports to show that process and physical properties are optimized at a low positive zeta potential. This is contrary on its face to our claim that zero zeta potential is optimum.

In case you wondered about the discrepancy, it results from what I have termed “cationic decay”, or the drift of the stock towards a less positive zeta potential with time. It represents the unbundling of the cationic chemicals which, in our early experiments, were not mixed homogeneously.

I must say this has been a difficult row to hoe. Cationic demand measurement has been globally adopted, DESPITE THAT FACT THAT THE MEASUREMENT IS NOT REPEATABLE. "Stay tuned."

John G. Penniman
www.papermaking-chemistry.com