| 摘要 |
<p>FIELD: building industry. SUBSTANCE: method involves preliminary milling waste paper and cardboard (22.5-25.6 wt.-%) to unit fiber (length is 2-3 mm), its mixing with boric acid (0.7-3.4 wt.-%) for 3-10 s, stirring the obtained mixture with filling agent (wood saw-dust, pile flax, hemp, jute, chopped straw and so on or their mixture at the ratio 1:0.5-1:1.5) at amount 5 wt.-% for 3-10 s at addition of gas-forming filling agent (0.5-0.9 wt.-%) - a mixture of gypsum semihydrate and oxalic acid at ratio 7.5:1 and waste gypsum production (0.4-1.0 wt.-%) and stirring for 5-10 s. Dry cover is formed from the obtained composition, treated in magnetic field, thickened, wetted and impregnated with magnetized water. Water excess is removed under vacuum at four zones and product is pressed successively for 2 stages at definite pressure values and subjected for thermic treatment at 18 zones at definite temperature ranges. EFFECT: improved quality and suitable utilization of material. 2 cl, 2 tbl</p> |
