Haile et al. Bioresour. Bioprocess.
(2021) 8:35
Page 3 of 22
Fig. 2 Global consumption of paper by major countries
estimated on average around 55 kg/person per year. The utilization of paper and board is increasing year to year though digitalization is expected to influence produc- tion and consumption in different ways. The dominant countries like North America, Europe, and Asia and low producers and consumers like African countries are still utilizing huge amounts of paper. The key components in the paper are cellulose sheets. There are also other constituents derived from the woody and related raw materials. The raw materials for manu- facturing pulp and paper are ample and mainly consist of cellulose. Besides wood which is a chief source of cellu- lose, recycled paper and other cellulose bearing agricul- tural residues can be used as a raw material. The scenario in developing countries showed around 60% cellulose is obtained from jute, sisal, bamboo, bagasse, and similar non-wood resources. Wood is considered the primary raw material and the major source of pulp in paper production (Eugenio et al. 2019). The gross characteristic composition of wood indicates its major constituents are cellulose, lignin, and hemicellulose. It also contains a trace amount of extrac- tives of different types. Numerical observation revealed that wood contains around 40–50% of cellulose (Table 1) (Sjöström and Westermark 1999). Considering ultimate properties such as strength and printability of paper it is possible to use hardwood and softwoods separately or combined in the manufacturing process. (Liu et al. 2018; Asmare 2017). An onsite availability study has been conducted on paper mills in Ethiopia. According to the study report, 25 paper enterprises are assessed and of which 12 companies
Table 1 Composition of wood S. N Component
% Composition
1 2 3 4
Cellulose
40–50%
Hemicellulose
25–30 25–30 Minor
Lignin
Extractives
are effective in producing different kinds of paper prod- ucts with measurable production losses (Table 2). The main aim of the preliminary study was to deter- mine the availability of waste and possible ingredients for biomaterial synthesis. The production loss indicated the potential availability of wastes and allied potential ingre- dients from the mills. The availability study in the speci- fied country ensured a potential for conversion of pulp and paper mill biomass into biomaterials. Limitation to produce pulp indigenously can also be solved for the sat- isfaction of the demand for paper and paper products. Overview on pulp and paper manufacturing process The availability of raw materials for pulp and paper man- ufacturing is versatile and mainly cellulosic fibers from wood and selected plants are utilized. Besides wood used most widely in many countries of the world plant resources such as sugar cane residues, residues on cot- tonseed, and remnants from flax and rags are also used (Osman Khider et al. 2012; Asmare 2017; Enayati et al. 2009; Jahan et al. 2004; Tutus et al. 2010). Besides, in case of scarcity of virgin raw material resources recycled paper after proper after-treatment, through appropriate
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