This document summarizes the paper recycling process. It discusses the sources of recycled paper like households and retail stores. The recycling process involves sorting, pulping, screening, cleaning, deinking, refining, bleaching, and papermaking. Recycling paper provides environmental benefits like reducing landfill waste and saving trees, while also saving energy compared to producing paper from virgin materials. Recycled paper can be used to produce products like paperboard, boxes, towels, tissue, and notebooks.

1. RECYCLING PAPER
UNDER THE GUIDANCE OF: DR. BABU RAO GUDURI
PRESENTED BY: SUJAY PAWAR
(PG/M/2015/29)

2. CONTENTS
• INTRODUCTION
• WHAT PAPER IS RECYCLED?
• RECYCLED PAPER SOURCES
• RECYCLED PAPER PROCESSING
• ENVIRONMENTAL IMPACTS
• BENEFITS OF RECYCLING PAPER
• USES
• REFERENCES

3. INTRODUCTION
• Paper recycling is the process of turning waste
paper into new paper products.
• There are three categories of paper that can be
used as feedstock for making recycled paper:
mill broke, pre-consumer waste and post-
consumer waste.

4. PRECONSUMER WASTE
Pre-consumer waste consists of
wastes from the manufacturing
and papermaking process as well
as finished paper from obsolete
inventories.
POSTCONSUMER WASTE
Post-consumer waste consists of
paper, paperboard and fibrous
waste from retail stores, offices
and homes.

5. What Paper is Recycled?

6. Recycled Paper Sources
• Households
-Newspaper
-Mixed waste
• Retail and wholesale
-corrugated containers
• Offices, Institutions, Printers and converters
-High grade deinking

7. Recycled Paper Processing
• Sorting, Collection and Transportation
• Storage
• Re-pulping and Screening
• Cleaning
• Deinking
• Refining, Bleaching and Color stripping
• Paper making

8. Sorting, Collection and Transportation

9. Storage

10. Re-pulping and Screening
The paper moves by conveyor to a big vat called a pulper, which
contains water and chemicals. The pulper chops the recovered
paper into small pieces. Heating the mixture breaks the paper
down more quickly into tiny strands of cellulose (organic plant
material) called fibers. Eventually, the old paper turns into a
mushy mixture called pulp.

11. Screening
The pulp is forced through screens containing
holes and slots of various shapes and sizes.
The screens remove small contaminants such
as bits of plastic and globs of glue. This process
is called screening.

12. Cleaning
Mills also clean pulp by spinning it around in large cone-
shaped cylinders. Heavy contaminants like staples are
thrown to the outside of the cone and fall through the
bottom of the cylinder. Lighter contaminants collect in the
center of the cone and are removed. This process is called
cleaning.

13. Contaminant Removal
• Metals
• Chemicals
• Thread
• Plastic
• Paper clips, Staples
• Metal binders
• Ink
• Adhesives
• Wax
• Clay
• solvent

14. Deinking
• In the deinking stage, the goal
is to release and remove
the hydrophobic contaminants
from the recycled paper. The
contaminants are
mostly printing ink and stickies.
Several processes are used,
most commonly flotation or
washing.
• Small particles of ink are rinsed
from the pulp with water in a
process called washing. Larger
particles and stickies are
removed with air bubbles in
another process called
flotation.

15. Flotation Deinking
• The collector is added to the inlet
of the flotation. The process
temperatures are normally in the
range 45 - 55 °C. Air is blown into
the pulp suspension. The
collector has affinity both to the
ink particles and air bubbles,
causing them to attach. The air
bubbles lift the ink to the surface
and form a thick froth that can be
removed. Normally the setup is a
two stage system with 3, 4 or 5
flotation cells in series. Flotation
deinking is very effective in
removing ink particles larger than
about 10 µm.

16. Washing Process
• Wash deinking consists of a washing stage
where dispersants are added to wash out
the printing inks. When the pulp slurry is
dewatered (thickened), the medium to fine
particles are washed out. This process is most
useful for removing particles smaller than
about 30 µm, like water-based inks, fillers,
coating particles, fines and micro stickies.

17. Chemicals Used in Deinking
• Sodium hydroxide
• Soap
• Calcium salts
• Surfactants
• Hydrogen peroxide
• Talc
• Sulfuric acid
• Solvents

18. Refining, Bleaching and Color Stripping
During refining, the pulp is beaten to make the recycled
fibers swell, making them ideal for papermaking. If the
pulp contains any large bundles of fibers, refining
separates them into individual fibers. If the recovered
paper is colored, color stripping chemicals remove the
dyes from the paper.

19. Papermaking
The pulp is mixed with water and chemicals to make it 99.5%
water. This watery pulp mixture enters the headbox, a giant
metal box at the beginning of the paper machine, and then is
sprayed in a continuous wide jet onto a huge flat wire screen
which is moving very quickly through the paper machine.

20. The sheet, which now resembles paper, passes through a
series of heated metal rollers which dry the paper. If
coated paper is being made, a coating mixture can be
applied near the end of the process, or in a separate
process after the papermaking is completed. coating gives
paper a smooth, glossy surface for printing.
Cont...

21. Finally, the finished paper is wound into a giant roll and
removed from the paper machine. One roll can be as
wide as 30 feet and weigh as much as 20 tons. The roll
of paper is cut into smaller rolls, or sometimes into
sheets, before being shipped to a converting plant
where it will be printed or made into products such as
envelopes, paper bags, or boxes.

22. Environmental Impact
• Effluent Processing
• Sludge
• Contaminant disposal
• Refining, Bleaching and color Stripping

23. Benefits of Recycling Paper
• Recycling newspaper saves 14% of landfill space
• Recycling one ton of paper can save 17 trees
• Reduces sulfur dioxide emissions
• Most paper can be recycled up to 8 times to
create new products
• Leaves more trees for the sustainability of our
environment
• Saves energy

24. Recycled paper uses
• Paperboard
• Folding box-board
• Corrugated boxes
• Egg cartons
• Paper towels
• Tissue
• Toilet paper
• Newspaper
• Paper Bags
• Notebooks
• Calendars

25. References
• www.tappi.org
• wikipedia.org
• paperproject.org
• Technology of paper recycling by R.W.J
McKinney