Mixing capacity

Experimental Analysis of the Melting and Mixing Capacity of a Screw... 

The mix capacity was also varied using the full-size mixer with the same concrete mixes and admixtures. Results are given in Table 3.10 where it will be seen that the effect of batch size is only slight and, in the higher cement content mixes, shows a trend towards higher air content as the capacity of the mixes is approached. 

Table 3.10 Slightly higher air contents are obtained as the volume of mix approaches that of the mix capacity, particularly for the higher cement content mix ...

The expts were conducted in stainless steel sigma-blade type mixers with proplnt mixing capacities of 60, 600 and 2000 lbs, respectively. Radioactivity measurements on samples taken from various locations in the batch at different mixing times were performed with a sodium iodide scintillation detector system... 

Most of the indices of the mixing capacity in the left-hand side column in Table 2.1 are related to the mixing rate—residence time for the flow system (e.g., ratio of the standard deviation of the probability density distribution of the residence time to the average residence time residence time is the stay time of the inner substance in an equipment), circulation time for a batch system (e.g., ratio of the standard deviation of the probability density distribution of the circulation time to the average circulation time circulation time is the time required for one circulation of the inner substance in an equipment), mixing time (e.g., the time required for the concentration of the inner substances at a specific position in the equipment to reach a final constant value within some permissible deviation), and so on. 

Index of Mixing Capacity Index of Mixing State... 

When the base of the logarithm is e, the denominator in this equation becomes unity and Eq. (2.6) becomes simpler. The mixing capacity defined by Eq. (2.6) has a value from zero for the piston flow to unity for the perfect mixing flow ... 

It is not easy to precisely express the RTD function obtained by experiments by using a formula. Therefore, in order to calculate the mixing capacity practically, it is convenient to treat the residence time as discontinuous time, that is, as a function of the discrete time in an interval of At (dimensionless residence time interval). From this, the probability that the observed element reaches the outlet in r, t +At is shown as Efr At, and the amount of uncertainty regarding... 

Challenge 2.1. Relationship between the mixing capacity and the number of tanks in series of perfectly mixed vessels model (a string of perfectly mixed tanks of equal size model)... 

Figure 2.4 (a) SPMV model in a flow system, (b) RTD curves in SPMV model in a flow system, (c) Mixing capacity change with number of tanks in SPMV model in a flow system. 

To clarify the relationship between the mixing capacity M defined by Eq. (2.10) and the number of tanks n of the SPMV model. 

Figure 2.4(c) (Mixing capacity M versus number of tanks n). 

Challenge 2.2. Relationship between mixing capacity and impeller rotational speed and set of positions of the inlet and outlet in a flow-stirred vessel... 

The tracer is injected at the inlet by using an injector in the form of an impulse, and the concentration of the tracer at the outlet is measured by the electrode conductivity probe. Based on the change in concentration with time, the mixing capacity M defined by Eq. (2.10) is calculated. 

Figure 2.5(c) (Mixing capacity versus dimensionless time for each set of positions of the inlet and outlet when Q = 41/min). 

As observed, it becomes possible to quantitatively express the degree of the mixing state based on the spatial distribution of the concentration of tracer in the equipment. Accordingly, the evaluation of the mixing capacity of the operation/equipment becomes possible by using the change in mixedness with time. 

The order of the mixing capacity of each impeller style is considered to be identical to that of the mixing rate described above. Therefore, the order of the mixing capacity of each impeller style is considered to be the same as that of the mixing rate. 

The whole mixing capacity defined above takes a value from zero for piston flow to unity for perfect mixing flow ... 

Needless to say, the whole mixing capacity can also be derived by taking the average of the local mixing capacity (MGj(R) or Mlj(R) or MLj(R)) in all the regions. 

The mixing capacity for the case where only the inflow from a specific o-region to each region occurs is a modified index that is obtained by setting 1 = 0 and then multiplied by VT/V0 in Eq. (2.30). The expression of the modified index becomes identical to the definition of the mixedness in the case of the transient response method in the previous section. This is only the contact point with the mixedness based on the transient response method. The CPD can be calculated if the transient probability of the inner substance is known. 

Until now, a quantitative evaluation of the local mixing capacity and whole mixing capacity based on the movement of the inner substances among regions has been shown. 

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