FiberLean MFC:

FiberLean MFC:

High solids product from MFC/ mineral composite materials allow attenuated performance of functional minerals and cellulose microfibrils in a wide range of industrial applications

May 14 2018

David Skuse and Sean Ireland
FiberLean Technologies Limited

Introduction

  • Microfibrillated Cellulose (MFC) known for many years
  • Utility for increased bonding in fibre-based structures, viscosification, re-inforcement
  • MFC use has been limited by high process energy requirement and equipment complexity
  • We have developed a cost effective grinding-based method for the production of mineral/ MFC composites from minerals and cellulose pulp
    • Cellulose fibres are co-processed with mineral particles. The mineral particles act as micro-grinding media, thus, reducing the energy requirement
    • The process can be accomplished using robust, industrially proven grinding equipment
  • Commercialised as FiberLean® MFC
  • We have been able to produce mineral/ MFC composites with a wide range of pulps and minerals
  • FDA FCN for food contact paperboard
  • 8000 dry metric tonnes pa of fibril capacity (40 000 dry metric tonnes of mineral/ MFC composite) installed and operational across three continents. Further capacity under construction
  • Processing and handling of mineral/ MFC composites are dominated by the high viscosity of MFC arising from presence of high surface area hydrophillic fibrils. Typical fibre solids is ~2%

Processing and handling of mineral/ MFC compositesPhotograph (a) and micrograph (b) of mineral/ MFC composite showing the high viscosity and fibrillar structure

Typically, use of mineral/ MFC composites in a web-based system and with a concomitant filler increase is associated with:

  • use of mineral/ MFC composites in a web-based systemExcellent performance stability
  • Increased initial wet web strength
  • Minimal impact on wet end chemistry
  • Overall positive impact on drainage
  • Improved dry mechanical properties
  • Improved opacity
  • A much tighter sheet (reduced porosity)
  • Improved coating hold out
  • Improved smoothness
  • Maintaining bulk when fibre is replaced by higher specific gravity filler is a challenge but can be managed

Performance observations: Wood free paper filler top-up

Performance observations: Wood free paper filler top-up

Product characterisation and test methods

  • Product characterisation is straightforward; solids; percent of solids that is fibre, viscosity and in-house tensile testin-house tensile test

In-house tensile test and handsheet data show good correlation for a range of mineral/ MFC composites samples prepared with varying processing conditions.

Running full-scale trials with low solids products

  • Running full-scale trials with MFC difficult due to low solids, viscous product
  • Our solution was to build a production plant producing a dewatered crumble product
  • Approximately 80 full-scale paper machine trials to date
Mineral MFC composite filter cake product form

Mineral MFC composite filter cake product form

Mineral MFC composite production plant in the UK

Mineral/ MFC composite production plant in the UK, 2000 dry metric tonnes pa of fibril capacity. Operational since Q4 2013

Product form

  • Slurry (~2% MFC fibre solids)
  • Bottles and barrels, Transitanks, Trucks and ISO tanks
  • Filter cake (~10-15% MFC fibre solids)
  • Buckets, barrels, big bags
product form
product form product form

Product form

  • Slurry (~2% MFC fibre solids)
  • Bottles and barrels, Transitanks, Trucks and ISO tanks
product form
product form product form

Product form

  • product form - filter cakeFilter cake (~10-15% MFC fibre solids)
  • Buckets, barrels, big bags

 

 

 

 

 

 

Filter cake
Bag weight ~ 1000 kg (~2200 lb) = 150 kg (~330 lb) dry MFC

Largest shipments to date
292 bags = ~44 tonnes (~48 short tons) of dry MFC

Regulatory clearance

  • Cleared through Environment Canada, Health Canada, US EPA and US FDA (FCN 1582, for 5 wt.% fibrils in packaging board)
  • BfR application filed for consideration under recommendations XXXVI, XXXVI/1, XXXVI/2, and XXXVI/3

Mineral/ MFC composites with a range of fibers

mineral MFC composites with a range of fibers

(BSK -Bleached Softwood Kraft, UBSK – UnBleached Softwood Kraft, Euca- Eucalyptus, TMP – Thermo-Mechanical Pulp, DIP – DeInked Pulp. Control – admix of BSK1 and mineral), 80:20 60%<2um GCC: fibre

 

 

 

It is possible to prepare effective mineral/ MFC composites from a wide range of fibers

Mineral/ MFC composites with a range of minerals

mineral MFC composites from a wide range of minerals

 

 

 

 

 

 

 

 

It is possible to prepare effective mineral/ MFC composites from a wide range of minerals

 

 

 

 

 

 

 

Scanning electron micrographs of mineral/ MFC composites samples
prepared with a range of different minerals (80:20, mineral/ NBSK, mineral/
MFC composite)

Mineral/ MFC composites evolving performance

  • There have been improvements in product tensile and viscosity performance since the initial launch in 2014. With more to come
mineral mfc composites evolving performance

Tensile and viscosity performance of a series of laboratory and pilot scale prototype mineral/ MFC composite products (80:20, mineral/ MFC composite)

Mineral/ MFC composite performance comparable to other MFCs

Paper breaking energy versus mineral filler content

Mineral/ MFC merchant plant concepts

mineral mfc merchant plant concepts

Mineral/ MFC merchant plant concepts

  • A high solids MFC product form is highly desirable since it allows merchant sales
  • It is easy to dry MFC but the challenge is effective redispersion in water at customer location
  • Mineral/ MFC composites can be dried to high solids and then redispersed in water with low energy input and the original properties restored

mineral mfc merchant plant concepts table

Mineral/ MFC merchant plant concepts: High solids product forms

High solids product forms

High solids mineral/ MFC composite product form ((50:50, 60%<2um GCC/ NBSK mineral/ MFC composite, 51% solids))

High solids Mineral/ MFC Composites: product stability

High solids Mineral/ MFC Composites: product stabilityMineral/ MFC composites display peformance stability for > 150 days when stored in intermediate bulk containers under ambient conditions

Applications

mineral/ mfc composite applications

Conclusions

  • Mineral/ MFC composites are produced using a cost-effective, robust process and have proven full-scale availability
  • Mineral/ MFC composites can be produced using a wide range of minerals and pulps
  • The tensile and viscosity behaviours of mineral/ MFC composites have improved since the intial product launch in 2014
  • Mineral/ MFC composites give at least equivalent behaviour to other MFCs in paper and board applications
  • High solids mineral/ MFC composite product forms can be fully re-dispersed to their original properties and allow the operation of merchant plants
  • We believe that mineral/ MFC composites are an important additive for a wide range of applications
  • These mineral/ MFC composite materials have been commercialised as FiberLean® MFC
No Comments

Post A Comment