Pneumatic conveying of mono-sized particles was previously analyzed with two models of uniform flow and annular flow. Those results are applied in this report to elucidate the relationship between particles hold-up and velocities of air and particles in a vertical line where mixtures of two different particles are transported. The relationship can be expressed with the same type of equation as the one obtained previously.
v_F=b_mix+m_mixεv_P/1-ε
The constants b_mix and m_mix are combination of the characteristic constants of both components multiplied with their weight fraction. This linearity was well satisfied with the experimental data of b_mix and m_mix.
The change of weight fraction in the line was predicted by the model fairly well but there was some deviation of its theoretical value from the actual one.

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High density and low velocity pneumatic transportation of granules, the conveying state of which is like the state of moving bed, has been obtained using both a reciprocating feeder and an orifice attached at the exit of the tube. In this experiment the maximum velocity of a particle was 7.5cm/sec. The authors have named “Rod-like flow” for this state of pneumatic transportation and have discussed the pressure drop of gas and the flow rate of granules at the steady state. It has been concluded that the pressure drop is approximately expressed by Ergun's equation using the porosity εmf at the minimum fluidization. It is shown that the formula which expresses the flow rate of granules can be related to the effective superficial gas velocity u*=u_f-u_mf (u_f: superficial gas velocity, u_mf: superficial minimum fluidizing gas velocity) and the opening of the orifice attached at the exit of the tube. The empirical equation of flow rate has been obtained as follows.
εu_p=α′{(D_e-2D_p)/D_p}ⁿ′(u*)ⁿ

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In the blow-tank conveying system materials are charged and sealed up in the tank at the beginning of each transport cycle and then blown off into a conveying pipe by a high compressed air. By this system it is possible to transport the materials in high concentration over a long distance. In recent years the application of this system has been widely made in many fields of industory, but investigations into the performance characteristics are scarce with its practical importance.
This work is made to investigate into the effect of the following terms on the characteristics; tank inlet pressure; initial charging fraction of solids in the tank; length of conveying pipe and primary air fraction.
From the experimental study, the following results are obtained. The mass flow rate of solids is proportional to the initial charging fraction of solid in the tank and to the tank inlet pressure. The efficiency of transport of solids of a given mass flow rate is better when a large value of initial charging fraction and primary air fraction and a small value of tank inlet pressure are selected.

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