The Paper Making Process, Part 2: Paper Making in Developing Countries

Statistics show that there is a strong link between the per capita income of a country and the amount of paper consumed. Whilst in the industrialized countries of the world consumption can be as high as 300 kg per capita per year, in some of the world’s poorest nations this figure can be as low as 1 kg, and rarely exceeds 15kg per capita per year in the developing world. Illiteracy is also closely associated with low levels of paper consumption, as few books or newspapers are available and schools lack basic resources. As per capital income grows, and society demands higher rates of literacy, so the demand for paper grows. Only with indigenous manufacturing capacity and locally sourced raw materials can this demand be met at a reasonable cost, avoiding import taxes, high purchase prices and loss of valuable foreign exchange.

Technically, there are several ways of meeting this demand. Large-scale paper making plants are one solution, but these larger plants often fail to meet the broader socio-economic requirements of developing nations. Smaller mills provide higher levels of employment, not only in the mill, but amongst associated industries, such as waste paper collection and machinery manufacture. Smaller mills are more flexible in their acceptance of raw materials. With the growing concerns over deforestation and natural resource depletion in many parts of Asia, Africa and South America, the use of agricultural residues such as baggase, wheat or rice straw for paper production, is often a necessity. The product range is also more flexible in small paper making plants, with the ability to cater for a variety of demands, albeit, sometimes, with a slightly lower quality than that of the larger dedicated plant.

With many governments now opting for rural and regional development as a model for their country’s growth, it is becoming more popular to assist in the development of small-scale industries in the regions. Paper making is an ideal example of how small industry can be developed to make of use of local resources, both in terms raw materials and energy, while cutting transport costs and catering for a slowly growing local market.

The initial capital investment requirement for small-scale papermaking plant is also lower and therefore more attractive to prospective small business people with limited capital to hand. This is especially so in countries like India where machinery and equipment for manufacture is produced in-country. Government measures are often needed to support such initiatives, and where such measures are put in place small-scale industry can flourish.

Types, characteristics and physical properties of paper

Paper comes in an enormous variety of shapes, sizes, qualities, grades, colors and finishes. There are as many types of paper as there are uses for paper. Some common types of paper in production include the following:

  • Printings and writings (stationery paper)
  • Currency paper
  • Newsprint
  • Hygienic tissue paper
  • Corrugated case material § Photographic paper § Light-weight coated paper for magazines
  • Wrapping and packaging paper
  • Paper card
  • Solid board for boxes

The above probably make up 80-90% of all paper produced

Physical properties of paper. Some of the typical characteristics used to determine paper quality are given here. The types of tests that will be carried out on a batch of new paper depend upon the use for the paper.

  • Weight in grams per square meter (referred to as gsm or grammage)
  • Brightness / shade
  • Porosity
  • Thickness or calliper (measured in microns) § Smoothness / gloss § Density or bulk (a function of the previous two qualities)
  • Oil-resistance
  • Moisture absorption
  • Tensile strength § Moisture content
  • Burst
  • Folding
  • Optical properties

The quality of paper is often controlled by the National Standards organization in the country concerned. It is always worth consulting these Standards well in advance if contemplating setting up a paper manufacturing facility.

Raw Materials and Additives

Raw Materials

For economic production of paper there must be a secure supply of suitable raw material at a reasonable price. Fortunately, there are many fibers which are well suited to paper making. In tropical developing countries, where wood is often in short supply there are a number of other sources of fiber, often by-products of the agriculture or textile industries. Below are some examples.

Table 2: Raw materials commonly used for paper production

Raw Material Source Suitability
Straw (e.g. from
wheat, barley or rice)
Between 5 and 10%
of all straw which is
produced is burned.
Short fibered (1.5mm), it is often mixed with
other pulp to provide a suitable pulp stock for
a variety of uses.
Bagasse* From sugar cane
after the sugar has
been extracted.
Slightly longer fiber than straw. Suitable for
high quality writing and printing paper.
Maize stalks Remaining after
maize harvest.
The high moisture content and need for
collection make maize stalks suitable only for
very small-scale production. Properties
similar to straw.
Bamboo Grown for use. Fibre length of 2.7mm, suitable for all types
of paper making without addition of other
fibre. Supply is often limited.
Cotton Cuttings, lint and fluff
from cotton mills.
Cotton is a high value fabric and is therefore
only used for specialist papers. Has a fibre
length of 25 32mm.
Rags (from cotton material) Collected Often require sorting and bleaching.
Flax A residue from the
manufacture of linen.
Long fibers make this material suitable for
high quality paper.
Hemp and sisal From old ropes and
tow from ropemaking
factories.
6mm fiber length, processing similar to that
of cotton.
Jute From old sacks and
hessian.
Jute does not bleach well and is therefore
used for its strength rather than for high
quality grades

source: www.practicalaction.org

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