Frequently Asked Questions
Function, Difference to Standard Paper Sacks, Use
1. What is the D-Sack®?
It is a cement sack that is introduced directly into the mixer and disintegrates completely during the mixing process. In fact the sack disappears in the mixer, becoming part of the mix and eliminating the need to dispose of the used packaging.
2. How is the concept different to standard building material sacks
It disintegrates in the mixer and has a coating layer that provides the barrier and shelf life properties to the sack, whereas normal sacks do not disintegrate in the cement mixer and have a plastic film to provide the barrier and shelf life.
3. How do the paper fibres and coating which are now present in the mortar or concrete affect the mixed product?
Test results from both LafargeHolcim and third party testing show no effect of the sack constituents on the properties of the mixed concrete or mortar product. It is important to point out that the sack is, by weight, only 0,05% of the final product (i.e. the concrete or mortar).
4. For which products is the sack suitable?
Cement 25, 35kg
5. Is the sack suitable for all products?
The sack is suitable for packing of cement for the mixing of mortar and concrete. It is not suitable for packing pre-mix mortars and other mineral based powdered materials as the sack’s disintegration requires the friction, moisture and mechanical action present in the cement drum mixer. These conditions are not present with other mixing processes.
6. How resistant is the sack to moisture and rain?
It provides the same level of shelf life as a standard paper cement sack with a slit free film.
7. Will the sack not dissolve in rain?
No, since the paper is protected by a barrier coating.
8. How is the paper made disintegrateable?
The technology used to achieve this is patented and a secret.
9. What is the disintegrating mechanism?
The technology used to achieve both moisture protection while simultaneously providing a disintegrating sack is patented and a secret.
10. Does the filled sack require any different handling?
Handling should take place according to our general handling instructions and thus there is no difference to a standard paper sack.
11. How do I dispose of the sack?
The sack disappears in the mixer and disposal is thus not necessary. If you have some empty sacks which were not thrown in the mixer, these can be disposed of in the normal channels used for paper sacks. These channels are dependent on the country in which the sack is used.
12. What is the difference between dissolve and disintegrate?
The difference is the level of disintegration, dissolves means go into solution (like sugar dissolving in water) and disintegrate means to break up into smaller particles (in the case of the D-Sack, the paper breaks up into individual paper fibers which are distributed through the concrete/mortar mix).
13. How do you measure/test dissolvability?
Dissolvability is measured both by laboratory methods using only paper and water and also in real life concrete and mortar mixing tests where remaining packaging material is assessed by weight in relation to total packaging weight.
14. How do I know if the sack has been mixed properly, i.e. that it has disintegrated completely?
The concept is designed to disintegrate in a concrete or mortar mixing process within 6 minutes. This was extensively tested during the development of the product to ensure that mixing times are the same as when using non-disintegrating cement sacks. If the advised mixing procedure is followed, then the sack will disintegrate.
15. Apart from disintegrating, does the sack perform differently to other building material sacks?
No, it has the same performance in terms of filling rates, moisture protection, strength etc. than normal paper cement sacks.
16. What shelf life does the sack offer?
It provides the same level of shelf life as a standard paper cement sack with slit free film.
17. How have you measured this shelf life?
This is measured by testing the water vapour transmission rate in a climate chamber in 38 degrees centigrade and 90 % humidity.
18. Is the shelf life guaranteed?
Since climate variations are vast depending on geographical location and storage conditions – there is no guaranteed shelf life, just as there is no guarantee for any other paper sack.
19. Is the sack available in brown?
20. Why is the sack not available in brown?
D-sack is a way to differentiate your product and we believe that this is better done with a white sack. Brown paper is also difficult to disintegrate inside the mixer due to the high lignin content of brown papers. Lignin occurs naturally in the tree and is the ‘’glue’’ which binds the wood fibres together and when lignin is present in paper, it is naturally stronger and disintegrates less easily than white paper.
21. Does the paper print normally?
Yes, in fact the print quality is quite exceptional, making your brand stand out from the rest. The outer ply is a coated paper and therefore some adjustments to the ink formulation may be needed, but these adjustments are all within the capabilities of paper sack manufacturers.
22. How does the D-Sack’s paper differ from Quickfill paper?
The inner ply is a specially developed QuickFill quality, i.e. it is a high porous paper with special disintegrating properties. The outer ply is a coated paper and has little in in common with QuickFill paper grades but is quite similar in strength.
23. For how long is the sack expected to perform to specification.
Due to the fact that the sacks are stored and used in conditions/circumstances outside our control, we cannot guarantee their performance forever - the sacks will perform to specification for one year after manufacture if stored and handled correctly.
24. Are there any special storage conditions required for the D-Sack® sacks prior to filling?
No, the sacks are to be transported and stored in the same way as other paper sacks; see our handling guidelines for more details.
25. What advantages does the D-Sack® sack offer over a standard cement and Mortar sack?
This new packaging has significant benefits, namely:
1) Improved environmental performance:
a) Waste is eliminated – the leftover sacks do not have to be disposed of and less cement is wasted in the mixing process.
b) Cement utilisation is improved – all the cement in the bag ends up in the mixer and none spills into the environment
c)Negative carbon footprint – improved cement utilisation and no CO2 emissions from bag disposal. The CO2 is bound in the concrete/mortar.
2) Health and safety performance is improved
a) Worker’s exposure to powdered cement is reduced significantly - no cement is spilt during the mixing process and workers do not come into contact with powdered cement.
b) Risk of injury is reduced - the sacks do not have to be cut open with sharp tools
c) Ergonomics are improved – less handling and lifting of the sacks
3)Work processes are simplified (time savings) – fewer steps in the preparation of the concrete/mortar result in less time needed for the mixing process.
4) Commercial benefits
a) The costs of disposing of the empty sacks are eliminated.
5) Innovation level of the product adds to the branding of the company using the sacks, increasing their image as an adopter of technology and improving their environmental credentials.
6) Printability is extremely good
26. Why should I use the sack?
The sack is an excellent differentiator and will allow you to boost your brand and improve market shares significantly. Additionally,
-In order to contribute to building a sustainable society, by using renewable packaging.
-To eliminate packaging waste, its treatment and transport costs
- Improve the health and working ergonomics of workers
-To ease work processes/steps in the preparation of concrete and mortar and thus save preparation time
- To minimize cement waste
27. What does the sack offer that PE FFS sacks do not?
This is a sustainable packaging made of a renewable raw material; paper. It disintegrates in the drum mixer which is impossible with PE FFS sacks. There is no packaging waste and a much lower carbon foot print on the environment.
28. What is the carbon footprint of the sack?
The D-Sack® has about 30 percent lower climate impact than conventional cement sacks. In a life cycle assessment conducted by IVL Swedish Environmental Research Institute, it was confirmed that D-Sack® is a CO2 capture in a hundred-year perspective. The sack is carbon dioxide negative because the carbon dioxide that was bound during tree growth and then incorporated into the paper remains in the concrete structure.
29. Is the sack made from sustainable sources?
The sack is made from renewable materials apart from a very small part of the coating system (the binder) that is partly based on non-renewable resources.
30. Is the paper made from sustainable sources?
Yes, BillerudKorsnäs works with sustainability as a top priority. Compliance with Swedish and European laws regulating forestry is the lowest level BillerudKorsnäs targets with regard to forestry management. BillerudKorsnäs strives to take responsibility for the whole value chain from the forest to the consumer and the recycling of our materials. We are certified both through ISO14001, an environment management system as well as through FSC and PEFC – both forestry regulating management systems. Our raw material is FSC and PEFC controlled wood certified.
31. Is the sack biodegradable/compostable?
Yes, the sack is made of biodegradable and compostable components.
32. Is the sack recyclable?
The sack will disappear in the mixer and become part of the final product. If however you have a need to dispose empty sacks - the sack is recyclable within the normal recycling systems in your country.
33. Is the paper repulpable?
The paper is repulpable in all normal paper repulping systems. However, the sack will disintegrate in the mixer and becomes part of the concrete/mortar mix and will thus not be recycled.
34. Where can I buy the sack?
As a consumer you can buy cement packed in the D-Sack at wholesalers and retailers of building products who stock this. As a cement producer you can purchase the D-Sack by contacting BillerudKorsnäs Sack Sales directly.
35.How does the sack fit in with BillerudKorsnäs’ strategy?
It is an innovation that provides additional value to the user and is based on renewable resources. It is strongly aligned with our strategy of challenging conventional packaging for a sustainable future.
36. Who and where was the sack developed?
The sack has been developed by the Sack Solutions team within BillerudKorsnäs together with the cooperation partner LafargeHolcim in France.
37. Why has BillerudKorsnäs developed the D-Sack?
The sack was developed in response to a clearly articulated need from builders to eliminate empty cement sacks (or packaging waste) and to improve worker health. Builders are also looking for a cleaner working environment, better ergonomics and reduced exposure to cement dust.
38. Do you have any other paper sack products in your development pipeline?
Yes we have recently developed and launched RainSafe, a paper sack that resists rain for a minimum of 4 hours - the RainSafe sack will resist rain for up to 8 hours if a sealable valve is use
39. Has the sack been patented?
Yes, the sack and paper are protected by patent.