the effect of binder pitch quinoline insolubles content - Coke Oven ...

More documents

Recommendations

Info

BINDER PITCH QI CONTENT – ALUMINIUM ANODE Table 4 gives the same ten anodes properties at optimum baked anode density. Again a comparison of the ten anode properties indicates quite consistent properties. Green Apparent Density Table 4. Optimized Anode Properties Pitch Level QI 3.9 wt.% 142 QI 5.6 wt.% QI 10.1 wt.% QI 16.1 wt.% QI 20.0 wt.% QI 24.3 wt.% 15 16 16 17 18 18 g/cc 1.614 1.630 1.621 1.641 1.646 1.633 Shrinkage Vol. % 0.65 -0.24 1.27 0.68 0.84 1.11 Baked Apparent Density Air Permeability Air Reactivity CO2 Reactivity Electrical Resistivity Thermal Conductivity Coefficient of Thermal Expansion Flexural Strength g/cc 1.544 1.551 1.569 1.569 1.580 1.581 nPm 0.45 0.54 0.32 0.73 0.30 0.25 % Residue % Residue µ Ohms/m 68.09 64.50 74.25 76.80 74.00 81.50 88.96 84.80 92.22 94.10 94.20 92.80 61.9 64.7 58.2 60.1 58.1 60.9 W/mK 2.64 2.52 2.85 2.72 2.77 2.75 *10^-6 @300°C 3.759 4.297 4.469 4.443 4.564 4.404 MPa 6.08 5.31 6.87 6.49 7.70 5.92
Conclusions COKE OVEN MANAGERS’ YEAR BOOK Despite all of the contradictions in the literature studied, we can draw some conclusions: Good quality anode carbon requires a balanced optical texture in the binder coke bridges that bond filler particles together – it should be sufficiently isotropic (i.e. disordered) to give the anode the required mechanical properties, most notably sufficient strength; but with enough anisotropy (order) to give acceptable levels of reactivity and electrical conductivity. Quite fortuitously, the presence of normal QI in pitch delivers such a heterogeneous structure. Normal QI physically inhibits the coalescence of mesophase by absorbing on to their surface during anode baking. As the mesophase grows, they push the normal QI into pockets – these pockets of isotropy in the baked anode impart the necessary strength to the binder coke bridges. The remaining matrix of binder coke, which is still relatively anisotropic, gives the binder coke bridges the desired reactivity and electrical resistivity properties. Since anodes made from 0% normal QI pitch have been found to have unacceptable anode properties [28], it is reasonable to assume that there will be a minimum normal QI level, below which the concentration of normal QI will be too low to deliver this desirable heterogeneous anode structure. The results of the studies reviewed suggest that this minimum normal QI level is less than 2% and may be as low as 1%. This needs to be confirmed experimentally. In several of the studies, reducing normal QI levels from >10% to
Page 1 and 2: COKE OVEN MANAGERS’ YEAR BOOK THE
Page 3 and 4: COKE OVEN MANAGERS’ YEAR BOOK Fig
Page 5 and 6: COKE OVEN MANAGERS’ YEAR BOOK As
Page 7 and 8: COKE OVEN MANAGERS’ YEAR BOOK Fig
Page 11 and 12: COKE OVEN MANAGERS’ YEAR BOOK obv
Page 15 and 16: COKE OVEN MANAGERS’ YEAR BOOK Con
Page 17 and 18: COKE OVEN MANAGERS’ YEAR BOOK Tab
Page 19 and 20: g/cc Vol. % COKE OVEN MANAGERS’ Y
Page 21 and 22: % Residue % Residue COKE OVEN MANAG
Page 23: Avg. Alpha * 10 -6 (@300° C) Mpa 4
Page 27 and 28: COKE OVEN MANAGERS’ YEAR BOOK and

the effect of binder pitch quinoline insolubles content - Coke Oven ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?