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                        TECHNICAL PAPER  #53
                      John Vogler & Peter Sarjeant
                         Technical Reviewers
                             Philip Barr
                          Dr. I. B. Sanborn
                          Dr. Robert Brooks
                           William Burger
                              Published By
        1600 Wilson Boulevard, Suite 500, Arlington, Virginia 22209 USA
                 Telephone: (703) 276-1800, Fax: (703) 243-1865
                   Telex: 440192 VITAUI, Cable: VITAINC
            Internet:, Bitnet: vita@gmuvax
                         Understanding Paper Recycling
                             ISBN: 0-86619-270-0
                 [C]1986, Volunteers in Technical Assistance
This paper is one of a series published by Volunteers in Technical
Assistance to provide an introduction to specific state-of-the-art
technologies of interest to people in developing countries.
The papers are intended to be used as guidelines to help
people choose technologies that are suitable to their situations.
They are not intended to provide construction or implementation
details. People are urged to contact VITA or a similar organization
for further information and technical assistance if they
find that a particular technology seems to meet their needs.
The papers in the series were written, reviewed, and illustrated
almost entirely by VITA Volunteer technical experts on a purely
voluntary basis. Some 500 volunteers were involved in the production
of the first 100 titles issued, contributing approximately
5,000 hours of their time. VITA staff included Marjorie Bowens-Wheatley
as editor, Suzanne Brooks handling typesetting and
layout, and Margaret Crouch as project manager.
The VITA Volunteers who wrote and reviewed this paper have many
years of experience in the paper industry. Jon Vogler, author of
Work from Waste, specializes in small-scale industries, particularly
those based on recycled materials. Peter Sarjeant, dedicated
to keeping alive the processes of the old master papermaker's
craft, is the author of Hand Papermakinq Manual. I. B.
"Bruce" Sanborn is associate director of research and development
at Consolidated Papers, Inc.; Phil Barr is fiber logistics manager
for the Weyerhaeuser Company; and Dr. Bob Brooks, also of
Weyerhaeuser, is the manager of pulp and paper educational activities.
William Burger, retired mechanical engineer from Kimberly-Clark
Corporation, assisted in the design of equipment for a
micro paper factory in Tanzania.
VITA is a private, nonprofit organization that supports people
working on technical problems in developing countries. VITA offers
information and assistance aimed at helping individuals and
groups to select and implement technologies appropriate to their
situations. VITA maintains an international Inquiry Service, a
specialized documentation center, and a computerized roster of
volunteer technical consultants; manages long-term field projects;
and publishes a variety of technical manuals and papers.
                    by Jon Vogler & Peter Sarjeant
Papyrus, from which the word paper is derived, is known to have
been in use as early as 3000 B.C. Developed in the Nile Valley,
it was made of strips cut from the papyrus plant stem, soaked,
and laid, first lengthwise, then crosswise, to form a mat. The
mat was then pounded and pressed into a thin sheet. Later,
similar processes elsewhere used other fibers such as silk.
True papermaking, which began in China about A.D. 105, uses an
entirely different process than the preparation of papyrus. It
begins with rags, straw, bark, wood, or other fibrous materials
that are chopped or cut fine. The fibers are pounded or pulped
until they are separated from each other and mixed with water.
Then the fibers are lifted from the water in a sieve-like screen
that allows the water to drain away, leaving a thin mat of fibers.
The fiber mat, which can be dried in place or removed and
dried separately, becomes a sheet of paper.
The earliest recorded manufacture of paper is credited to one of
the first "purchasing officers," Ts'ai Lun, head of the Imperial
Supply  Department of Emperor Ho of China. Ts'ai Lun experimented
with a  variety of materials: vegetable fibers, old hemp, cotton
rags, old fishnets, and mulberry bark. The paper produced was
cheap  and durable and the surface was good--and, significantly,
it was  made of recycled materials.
Early European papers were also made from recycled linen or
cotton rag. It was thick and rough, and the surface needed to be
"sized" with gelatin or the ink soaked in. Ulman Stromer set up
a mechanized papermill in Nuremberg, Germany, in 1390, using
water-powered hammers for beating the material, a method already
used by the Chinese. The craft accompanied the early settlers to
True mechanization was not achieved until 1799, when the Frenchman
Nicholas Robert built a machine with an endless wire mesh and
a pair of squeeze rolls. The device was taken to England and
marketed by two stationers, the Fourdrinier brothers. In 1804,
Brian Donkin, a millwright-engineer, built the first successful
papermaking machine, in Two Waters Mill, Hertfordshire, England,
and another in America in 1827. Crude early designs improved
steadily. By the end of the nineteenth century, Fourdrinier technology
was widespread; machines just over 2 meters wide supplied
25 metric tons per day to the growing market for newsprint.
Modern machines form paper in a continuous ribbon or web, not a
single sheet at a time as did the ancients. A good papermaker in
the olden days could make enough sheets in a day to weigh about
90kg. Today, an average machine makes 90,000kg per day! Much of
the paper produced ultimately ends up as waste paper, mountains
of it in some areas, which can often be recycled into other
papers and paper products.   The recycling of waste paper is the
focus of this paper.
Fibers are the fine, thread-like wisps from which paper, textiles,
and many other materials are made. Tear a piece of paper
and the fibers can be seen at the torn edge (more clearly with a
magnifying glass). Paper fibers are made of cellulose, the basic
building material of plants and trees. These materials can be
made into paper by pulping (breaking them down until the fibers
are loose and free of the substances that bind them), then reforming
them while wet and finally drying.
Softwood (or coniferous) pulps are used for tough wrapping and
packaging papers because of their long fibers; deciduous or
hardwood pulps provide fine fibers for printing and writing
To understand the waste paper industry it is important to know
about the major types of primary wood pulp used in papermaking:
mechanical pulp, and chemical pulps, which include kraft pulp,
and sulphite pulp. Pulp made of recyled paper is known as secondary
Mechanical Pulp
Mechanical pulps yield the most paper per ton of wood, but are
the weakest. They are made by pounding or grinding cellulose
fiber, such as wood or sugar cane bagasse. One of the commonest
uses of mechanical pulps is in the manufacture of newsprint.
Newsprint is relatively weak and loses its strength altogether if
wetted--a characteristic of mechanical pulp. It is used for rapid
newspaper printing because printing ink is soaked up and dries
very quickly, but it lacks the permanence of paper made from
kraft or sulphite pulp. Strong chemical pulp is often added to
mechanical pulp to give newsprint better strength. Mechanical
Pulp often contains tiny particles of wood that have not been
reduced to fiber and are visible to the naked eye, so paper made
from it is described as "woody."
Chemical Pulps
A stronger paper product is most cheaply made by pulping cellulose
fibers in such a way that they are not weakened by mechanical
damage. The wood or stalks are first reduced mechanically to
small chips, then cooked at high pressure with chemicals that
attack the bonds between the fibers. The chemicals most commonly
used are:
1.   Caustic soda and sodium sulfate, which produce coarse, very
     strong papers known as kraft, suitable for paper sacks and
     boxes that hold heavy weights.
2.   Various sulfides (such as ammonium and calcium), which
     produce finer fibers, suitable for making high quality,
     strong (but expensive) printing and writing papers (usually
     bleached white).
Secondary Pulp
Secondary or recycled pulp is made by vigorously agitating wastepaper
in water (usually in a hydro-pulper, a tank containing
rotating blades) to separate the fibers bonded during the original
papermaking process. As these bonds are weaker than those of
the original cellulose plant, hydro-pulping is a more gentle
process than primary wood pulping and consumes less energy. Even
so, each time paper is recycled it becomes weaker. Secondary
Pulp is therefore never as strong as the primary fiber from which
it was made. It can be almost as good, provided pure waste paper
of the same type is used. For example, pulp made by hydro-pulping
clean kraft sacks will make new sacks of only slightly lower
quality, particularly if mixed with a proportion of primary kraft
Pulp. If, however, the secondary pulp is made from material that
contains newspapers or quantities of dirt, dust, or clay, it w.11
not be strong enough to make sack paper.
Coated Papers. In some cases the matted, absorbent surface of a
paper is coated with a material that makes it glossy and smooth.
This coated paper is better for printing. Coated papers are
frequently used in magazines that are financed by the advertisements
printed. In the process of hydro-pulping coated wastepaper,
the coating is washed out; thus, the weight of fiber
obtained from a ton of coated paper is less, often by 20 percent,
than that obtained from a ton of uncoated paper. As a result, the
value of scrap coated paper to the paper mill, and its selling
price, will be lower.
If the coating is plastic or other material that will not disperse
in water, the waste paper will require specialized machinery
to recycle it and may reduce the value of more pure paper
with which it is mixed. The same is true of polyethylene film,
cellophane, glued paper, string, and any material that will not
break down in water. Some of the various coated papers can be
kept warm and wet in storage, then cooked in a hot caustic solution
in order to biodegrade and break down the coating to release
the fibers. Again, these papers require special machinery and
handling to recycle and they may not be as valuable as simpler,
plain papers.
Printed and Colored Papers. Both printing and tinting reduce the
value of papers to be recycled. They make the pulp and the paper
made from it dull grey in color unless bleached, which is expensive,
or de-inked, which is also expensive. Tinting colors the
pulp, which must then either be used for a limited range of
similarly colored products (or cheap, grey products), or must be
bleached. Therefore, white waste paper is more valuable than
similar material that is colored. Unprinted waste paper is of a
greater value than the same material printed.
A review of the papermaking industry is needed to understand the
ways in which waste paper is used. The manufacture and use of
paper is one of the world's biggest industries; it takes place
1.  pulp mills, which process wood chips or other materials to
    make pulp;
2.  paper mills and board mills, which use pulp or waste paper to
    produce finished paper and board;
3.  paper converters, which use paper or board to produce boxes,
    tubes, rolls of tissue, boxes of blank office paper, stacks
    of printing paper cut to standard sizs, etc.;
4.  printers, who usually buy from converters, although larger
    firms such as newspaper presses may buy directly from the
    paper mills; and
5.  "integrated" mills, which make pulp and then use it themselves
    to make paper.
These industries are huge, highly mechanized, and efficient.
There are many of them, so they compete fiercely for the available
markets. In countries where huge markets, skilled managers
and technicians, and the massive capital needed for investment
are available, handmade and small-scale paper manufactureres find
it very hard to compete. Large or small, where these industries
exist they represent potential markets for recycling waste paper--particularly
in developing countries which may lack other
resources for producing pulp.
Collecting waste paper is only difficult in a few poorer and more
rural parts of the world. Elsewhere it is abundant. Selling it is
often far more difficult, and only those who thoroughly understand
stand the market are successful. The different types of wastepaper
will therefore be considered in relation to their markets,
starting with the most valuable, and going on to those of less
Printing and Writing Papers
This category includes the best quality, most expensive papers
that bring the highest waste paper prices. They are mainly made
from bleached kraft and sulphite pulps. They are listed here in
descending order of value.
Computer printouts. This is usually used to make high quality
printing and writing papers.
Computer punched cards (tab cards). These may be buff-colored,
the most valuable, or colored.
Printer trimmings. These are the edge trimmings left when a
printer, boxmaker, or converter cuts the product to its final
size. Their high value results from cleanness, lack of printing,
and quality of the material. The value is increased if the
printer has kept different grades separate. If not, it is usually
worthwhile for the collector to sort the paper into different
grades and separate the printed material from the unprinted. This
labor-intensive activity needs no investment and can create many
jobs. White trimmings should be sorted from colored, but different
colors need not be separated. All may be sold to makers of
printing and writing papers.
Office papers. Such papers as invoices, ledgers, letter papers,
and record cards are included in this group. Printed or written
on papers are separated from blank paper, and whites are separated
from colors. Carbon paper and self-duplicating paper are also
separated from the rest.
Grease proof and plastic-coated papers, file covers and bookbindings,
metal file clips, string, and other office materials should
be removed. For sales to a big mill it is unnecessary to remove
staples or paper clips as the mill will remove these with magnets;
smaller mills may reject them. Envelopes, including a few
of the cheaper manilla variety (light brown), can be mixed in
with whites, as can cream-colored envelopes and papers in any
quantity. Adding machine rolls are usually good, white and unprinted.
Office papers may be sold to makers of printing paper
and high quality board.
School and letter papers. Letter papers may be of good quality,
but school exercise books are low in value, although they often
contain little ink (faint ruling does not count), because they
are mostly of mechanical pulp. They can be sold to makers of
printing and writing papers.
Pamphlets and magazines. Known in the trade as "pams," these are
the lowest grade of (printing) papers other than newsprint. They
are often coated and have heavy printing and large amounts of
color. They are not worth sorting unless a paper mill has a
Particular demand. They are heavy and it is easy to collect a
great weight quickly. They are best sold to makers of low quality
Newspapers. In some countries, newspapers are little in demand
due to their low strength. Telephone directories and some magazines
are also made from newsprint. Their principal uses are as
mixed waste paper for the manufacture of cheap flutings, grey
board (cheap cardboard), or the middle layers of multilayer
boards. There are three important exceptions:
o  In poor countries where little is thrown away, even low
   quality raw materials are in short supply.
o  Some countries that are heavily industrialized but lack
   their own sources of mechanical pulp, operate "de-inking
   plants." These remove ink from old newspapers by washing or
   bleaching. If such plants exist, or if it is economical to
   ship to countries that have them, prices for newspapers may
   be higher.
o  Unprinted newsprint is discarded by the newspaper presses,
   as are trimmings from the sides of the paper and reel ends
   (the material at the center of the reel of newsprint, which
   cannot be used for technical reasons). The former can be
   sold back to manufacturers of newsprint and low quality
    writing paper. The latter is clean and large enough to be
   cut up and sold at a high price for food wrappings.
Packaging Papers
Several types of packaging papers may be collected and recycled.
Again, they are described here in descending order of their
Kraft Sacks. Kraft paper is recognized by its strength and brown
color. It is used for large sacks, in two or three ply thicknesses,
or for smaller bags and wrapping papers. Occasionally, whitish,
bleached kraft is used. Watch out for sacks with polyethylene
linings, often used to protect chemicals from damp, which
are frequently reinforced with canvas or similar material. Tarred
Papers (waterproof) are unmarketable and reduce the value of the
load. Be sure sacks are empty.
An important decision is whether a greater profit can be made by
selling kraft for re-use as sacks or to board or kraft paper
mills for pulping. Re-use may entail repair or more sorting,
transportation, and selling costs, but this usually pays off.
Corrugated Cardboard. This is a brown board made of three layers.
The flat top and bottom layers are called liners and the corrugated
(wavy) center is the fluting. The liners are often made of
primary kraft, sometimes with secondary material (e.g., kraft
sacks or old corrugated boxes) mixed in. The fluting is made from
low quality material. Its function is to give stiffness to the
wall of the finished box. Pulp for fluting manufacture may have a
high proportion of mixed waste paper. Corrugated board is used to
make packing boxes or cartons and these are in demand everywhere.
Where there is no board mill, boxes can often be sold for re-use.
They are rarely contaminated with impurities, though some corrugated
board and sack paper has been treated with an invisible
resin, which gives it superior strength when wet. This material
will cause problems for the paper mill, since it will be very
hard to repulp. As a result, the value of this otherwise attractive
waste paper will be lower.
Special Packaging and Wrapping Papers. These come last in the
order of value because of the problems they cause with impurities,
or contraries. Much modern packaging mixes plastics, metals,
and other materials with paper and board, and it is difficult
or uneconomical to separate them. Greaseproof, cellophane,
and "wet strength" papers do not break down in water, cannot be
pulped, and are difficult to recognize and remove. The main
material is cardboard, containing a high proportion of cheap grey
board (sometimes inside an outer layer of good quality).  'he
amount of color printing is high too. Therefore, although such
papers or boards are expensive to produce, their value as waste
is no higher than that of mixed waste paper and may be lower due
to contraries.
Mixed Waste Paper
Mixed waste paper is the lowest usable grade, and may have almost
any composition. Grey board or multilayer board and similar
packaging materials not acceptable in any other grade, as well as
mixed, unsorted grades are satisfactory. A number of points are
worth noting:
o  This is the material often collected from municipal (town)
   garbage dumps by scavengers, or at specially built composting
   or refuse-sorting plants.
o  In a district of offices, factories, or wealthy homes, mixed
   waste paper may contain valuable grades, worth sorting out
   for separate sale if labor costs are low or time is available.
   It is important to realize that the material left,
   after better grades have been removed, may bring a lower
   price. This leftover material is principally made up of
   newspapers, packaging, and cheap cardboard. However, if
   local mills make corrugated board, toilet tissues, and cheap
   grey board, then separated kraft sacks, brown paper, and old
   cartons can go to the first and printing and writing papers
    to the second. These can be sold for higher prices and will
   not reduce the price of the remainder for making grey board.
o  Mixed waste paper can be an important source of material for
   recycling because, although merchants may have cornered
   supplies of high quality materials such as kraft, corrugated
   cartons, and printing and writing papers, quantities
   of mixed waste paper may still be obtained from municipal
   refuse by those who know what is valuable and what is not.
o  Opportunities exist here for creating more jobs. Once the
   principles of sorting have been taught, the work requires
   neither capital, technical skill, nor bodily strength and
   may be undertaken by the disabled or mentally retarded.
o  Mixed waste paper is worth half to a third of the value of
   old cartons, and this value is reduced if it is dirty, as
   is most material extracted from refuse dumps. By sorting
   out the higher grades and selling to the right market, a
   value equal to that of cartons may be achieved. The gain,
   however, has to be compared with the time and cost of sorting,
   selling, and transporting to several markets instead
   of only to one.
Waste paper can be collected from the following places, starting
with that which is likely to be the most profitable:
Computer offices produce the most valuable of all.
Printing shops usually sell the trimmings themselves, or else
they are collected by a merchant.
Newspaper presses almost always sell the edge trimmings and reel
ends themselves.
Offices throw out quantities of blank paper as well as office
records, letters, etc. If offices are small or located away from
the city center, they may not have made arrangements to sell
their waste.
Warehouses receive goods in sacks and corrugated boxes and often
discard these after unpacking. Quantities may be large.
Factories may also have large quantities of packaginq that they
do not want. These will get dirty on the factory floor unless
Shops receive goods in cartons; supermarkets and food stores
often give or sell these to their customers. Small shops may not
Produce enough to make a visit worthwhile unless there are other
shops nearby.
Householders may sell their waste paper. It may be dirtied by
food waste or ashes and may    not be in large enough quantities to
make a visit worthwhile. Still, thousands of people in many
countries make a living by collecting household waste paper,
sometimes paying the householder a small sum.
Refuse dumps receive only the paper that no one else has collected.
Refuse collectors often keep saleable materials, but
quantities of good quality waste paper continue to arrive at
refuse dumps all over the world.
Some method of transporting the collected material is essential.
This may be:
o  Sacks
o  Handcarts
o  Handcarts supported by a vehicle. When full, each cart is
   wheeled to the pick-up point, material is transferred to a
   vehicle, and the cart returns to collection. A good balance
   might be six carts to one vehicle.
o  Horse-drawn carts. For the stop-go process of waste paper
   collection, this is not "old fashioned" but highly effective.
o  Motor vehicle. Vans and trucks are a very expensive way of
   collecting any but the most valuable grades. With a wire
   mesh cage on top, to increase the load, they may be more
o  Trailers. These, also fitted with a cage top, make collecting
   even more profitable.
Cartons and boxes must be flattened before transport, by treading
down or "baling."
Waste paper is baled to reduce the costs of transportation and
storage. Baling involves squashing loose material into a densely-
Packed, square-shaped bundle that is then strongly tied, in two
or three directions, with wire or string.
Baling makes transport cheaper because a load of loose paper will
overflow before it reaches the weight limit that the vehicle  an
carry. Baling makes storage cheaper because material, as well as
being denser, can safely be stacked much higher.
Baling also reduces the risk of fire--a serious and ever-present
risk in waste paper processing. Baling prevents air reaching the
inside of the bundle, so flames only char the outside. However,
baling does not totally remove the risk of fire, particularly if
there is unbaled material lying around or if paper is wet, which
causes it to ferment and the temperature to rise high enough for
burning to begin.
Baling is most efficiently done in a press, a strong box equipped
with some means of compressing the material and holding it while
it is tied. In order of cost, this may be:
Treading Box: The simplest, cheapest baling press is a strong,
hinged four-sided wooden frame with no top or bottom but a joint
at one hinge. To operate, strong string is laid in the empty box,
which is filled with paper, well trodden down. The string is
tied, then the box joint opened to release the bale.
Hand-powered mechanical presses are used to obtain higher baling
pressures. Some use levers; some use screws with capstan nuts
(nuts fitted with long turning arms); and some use steel cables
wound (with a handle) around a spindle bearing a ratchet (a
device to keep the spindle from turning the wrong way). See
Figure 1.

upr1x11.gif (600x600)

Motorized screw presses can be used where electric power is
available. The press has a strong steel frame bearing an electric
motor. The motor turns a vertical screw, which moves the "platen"
(the strong, flat board that compresses the paper) up and down.
Bales are so tight that thick wire must be used to bind them.
Hydraulic baling presses can be built to almost any size and
power. They are expensive and need careful maintenance, especially
in countries where there is desert sand or gritty soil nearby,
but they are fast and very efficient. A wide range of automatic
Controls and automatic wiring devices can be fitted onto the
The markets for waste paper may be any of the following:
Merchants, who buy from printers, converters, and small collectors
and sell at a profit to the mills;
Exporters, who buy from anyone, to sell on the world market;
Mills, full-size industrial paper or board mills;
Papermakers, small-scale operations (usually plants producing
less than 30 tons per day); and
Small industries that make high-quality paper by hand, or that
use paper to make other products.
In countries where large-scale paper mills do not operate, or
where subtantial amounts of products are imported, there may be
opportunities to set up small-scale or even handmade papermaking
industries. These processes are described in the technical paper,
"Understanding Small-scale Papermaking." Readers should be extremely
cautious about any plans to compete with the economics of
large-scale papermaking within any given country, as that paper
makes clear.   Other possible uses of waste paper--other than for
repulping and paper production--are described below.
Banks, government agencies, and other organizations often shred
waste paper into thin strips to prevent confidential information
from being read. In England, this material is being marketed as
bedding for animals. One commercial company, Shredabed Limited,
markets both the material and the machinery for making it. They
claim that:
1. Pigs bedded on this material keep cleaner.
2. Poultry gain a little more weight and suffer less mortality
than birds bedded on wood shavings, straw, or sand.
3. Other livestock suffer less from respiratory (breathing)
problems when bedded on paper instead of straw.
4. Shredded paper is much easier to remove from pens and stables
after use. It spreads easily on fields and breaks down to
form excellent manure.
5. Shredded waste paper is easy to bale; as a result, the cost
of transportation and storage is low.
In cities where livestock sell for high prices, but straw or
other bedding materials are hard to obtain, this business may
yield good profits, particularly if combined with an operation to
sell the manure to gardeners.
A variety of strong, compartmented packing boxes can be produced
from old, corrugated cartons with a small amount of hand-operated
equipment (i.e., guillotine or paper shears, folder, punch for
slotted tray pieces, and stapling machine).
The old cartons are cut down to accurate size, refolded, and
stapled. It is important that the trays fit exactly and do not
move during transportation. To make the trays, off-cuts from the
boxes are guillotined to a standard size and punched.
Another process makes egg cartons from paper pulp using a small-scale
paper plant called the Super Melbourne. Waste paper is
first soaked, then pulped  and refined. Pulping can be done in a
domestic washing machine.
The equipment includes a refiner that reduces the pulp to basic
fibers. The slurry that results is poured onto a sheet of mesh
stretched over the forming tank of the Super Melbourne and a
valve in the tank is opened. The water draining from the tank
sucks moisture from the layer of pulp, which is then pulled from
the tank on its sheet of mesh. The layer of pulp is folded over
once and pressed between specially shaped dies, then it is laid
to dry.
The process employs four people but labor costs are reduced when
Super Melbourne machines are batched together for greater output.
Output is 60 egg trays per hour, or 60 sheets of paper 84 x 66
cm. The machine requires only 300 watts of electrical power. Most
of the water used is recycled. Floor space required is two
square meters for the machinery and five square meters for
More sophisticated machinery is availale for producing form 200
to 4,000 30-egg trays or equivalent products per hour      Such a
machine is made by Tomlinsons, but careful market research is
essential before contemplating the heavy cost of a machine that
tends to saturate any but the largest market.
All over the world the poor use waste paper to construct their
homes. It is cheap, and will offer protection from wind and sun,
but there the advantages end. It does not resist water, is highly
flammable, and is eaten by rats. It is also weak, tears easily,
and rots or becomes brittle after a short time. It is an unsuitable
material that demonstrates the desperate condition of those
who have no alternative. Asphalted paper, described below, is a
great improvement.
Low-quality, low-cost roofing sheets with a life of about five
years can be made from the very lowest grades of mixed waste
paper, grades that would not be acceptable for papermaking due to
the amount of dirt and contraries present. A factory with three
molding machines costs about $200,000 for plant and machinery
and can produce about 8,000 sheets daily, each about one square
meter in area (over two million square meters annually). About 35
people are employed and 50 tons of paper per week are used. In
India, the roofing material retails at around $0.25 per sheet; in
South America, at about $0.60 per sheet. The manufacturing process
consists of the following steps:
1.   The waste paper is washed and pulped in a hydropulper. A
     mechanical hammer mill or a Hollander beater may be used
2.   The pulp is passed through a screen, to remove dirt, grit, or
     other impurities, and a board-forming machine to produce a
     continuous length of board that is cut to length as it comes
     off the machine.
3.   The board is spread on the ground and dried in the open air.
     The edges are trimmed on a rotating slitter.
4.   The board passes through an oven at the end of which are
     corrugating rollers. The corrugated sheets are then trimmed
     again and stacked in cradles.
5.   Next, they are dipped in a bath of hot asphalt. (Asphalt is
     flammable so the means of heating must be carefully chosen.
     The asphalt hardens rapidly at air temperature and the sheets
     are unloaded and stacked.
6.   When quite hard the sheets are either:
     o   taped in bundles for sale as third quality;
     o   sprinkled with mineral chips (while asphalt is soft) prior
        to packing as second quality; or
     o   hand painted and packed as first quality.
In Canada and the United States, there has been some experience
using shredded waste paper as a thermal insulation material (a
material that keeps warm houses warm and cool houses cool.  The
thermal efficiency (i.e., the effectiveness in preventing movement
of heat) of the shredded and fluffed-up waste paper is
almost as good as glass fiber. To guard against fire, the paper
is soaked in a solution of borax or alum, or other fire retardant,
and then dried. Such material is much cheaper than other
thermal insulators and could be used widely where no straw is
available, provided each batch is tested to ensure that the fire-retarding
treatment is effective. It should be noted that rodents
like the salty treated waste paper for bedding and penta-chlorphenol
Phenol is sometimes used against them. This is carcinogenic, however,
and very hazardous to use.
It is possible to pulp waste paper, compress it into briquettes,
sun-dry these, and burn them as fuel. However, these briquettes:
1.  produce sooty smoke, making them a poor choice for cooking or
    use in the home;
2.  burn poorly, unless made as very small sticks; and
3.  give out low heat.
Only in the absence of any conventional fuel are they likely to
be regarded as acceptable for domestic use. Industrial users have
tried "refuse-derived" fuel pellets made from municipal garbage
but these have not proved satisfactory. Undoubtedly, there is a
Potential here but research and development are needed.
Ainsworth, J.H. "Paper the 5th Wonder," Thomas Printing and Publishing
     Company, 1959.
Appropriate Industrial Technology for Paper Products and Small
     Pulp Mills.   Vienna, Austria: United Nations Industrial
     Development Organization (UNIDO) , 1979.
Brook, S. "The Fine Art of Printing," Atlantic Monthly, April,
     1974 (112-115) .
Becker, W.J.  "The First Ten Years of the Fourdrinier,"   Paper
     Trade Journal, April 17, 1972 (34-41).
Becker, W.J.  "The First 145 Years of the Paper Machine in the
     U.S.," Paper Trade Journal, May 27, 1972 (140-150).
Casey, James P.  "Papermaking," Pulp and Paper, Vol. II, New
     York, New York: Interscience Publishers, Inc., 1960.
Goodwin, Rutherford  "The William Parks Paper Mill at Williamsburg,
     Virginia", Lexington, Virginia: Bibliographical Society
     of America, 1939.
Hunter, Dard Papermaking Pilgrimage to Japan, Korea, and China,
     New York, 1936.
Hunter, Dard Papermaking, New York, New York: Alfred A. Knopf,
Hunter, Dard Papermaking in the Classroom, the Manual Arts Press
     Peoria, Illinois.
Hunter, Dard "Watermarking Handmade Papers," Scientific American,
     March 26, 1921.
Norris, F.H. Paper and Paper Making, New York, New York: Oxford
     University Press, 1951.
Sarjeant, Peter T. Hand Papermaking Manual. Covington, Virginia:
     Paper Make, 1976.
Small-scale Paper-making, ILO Technical Memorandum No. 8.
     Geneva, Switzerland: International Labour Office, 1985.
Sweetman, J. "Making Paper by Hand," Appropriate Technology,
     Vol. 3, No. 4. London: Intermediate Technoloqy Publications
Thomas, C. The Paper Chain. London: Earth Resources Research
     Ltd., 1977.
Tsein, Tsuen-Hsuin  "China, the Birthplace of Paper, Printing and
     Moveable Type," Pulp and Paper International Journal, February,
von Hagen, V.W. The Aztec and Maya Papermakers, New York, New
     York: Hacker Art Books, 1944.
Western, A.W. Small Scale Pulp and Paper Manufacture, London:
     Intermediate Technology Publications Ltd., 1979.
                      EQUIPMENT SUPPLIERS
             Paper Mill Plant and
             Machinery Manufacturers Ltd.
             181 S V Road
             Jogeshwari, Bombay
             400060 India
             Hindon Engineering Works
             Clubley, Bajoria Marg,
             Saharanpur 247001
             UP India
             Indo Berolina Industriea, Pvt. Ltd.
             I.B.I. House
             5-86 Andheri Kurla Road
             400059 India
             Jessop and Co Ltd.
              63 Netaji Subhas Road  
             P.O. Box 108
             Calcutta, India
                        SOURCES OF INFORMATION
Association of the Pulp and Paper Industry
One Dunwoody Park
Atlanta, Georgia 30341
Write for free four-page booklet, "How You Can Make Paper":
     American Paper Institute
     260 Madison Avenue
     New York, NY