الفهرس 
Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
Rakta is considering a 100 t/day deinking unit for production of bleached pulp from office waste paper in case it is forced to close down its polluting rice straw production line. Implementing of the deinking project is in need of basic data concerning deinking evaluation of both locally available and needed imported office waste, evaluation of bleachability, physical properties, environmental impact and production cost of the bleached deinked pulp versus bleached rice straw pulp.
The experimental part involved construction of pilot units (a high consistency hydrapulper and a deinking cell) to simulate actual production units. The obtained results indicated that conventional alkaline deinking (with 1% NaOH, 1% H2O2, 4.7% Na2SiO3 Rs 1100 Henkel surfactant and 0.2% DTPA-Na5) of local mixed office waste /books followed by 1% peroxide bleached pulp of 82.5 G.E brightness (vs only 78 G.E brightness for bleached rice straw pulp), and better physical properties (4.72 Km breaking length, 33.93 burst, and 81.77 tear). Peroxide bleaching is preferable to hypochlorite bleaching since the latter gave inferior 2 G.E decrease in brightness and 10% less in physical properties. Alkaline deinking of low grade relatively inexpensive American office waste paper gave lower brightness (56.2 G.E) and lower physical properties in comparison to local office waste, while better quality but expensive Asian office waste paper gave high brightness pulp (85 G.E) of comparable physical properties to Rakta,s pulp. Alkaline deinking of office waste resulted in drastic reduction (91%) of environmental effluent load in comparison to very polluting rice straw bleached pulp.