Separative capacity definition

This angle plate gravity separator removes suspensions of solids from a dilute liquid. The unit is more compact than a box-type settler due to the increased capacity achiev ed by the multiple parallel plates. The concept is fairly standard (U.S. Patent 1,458.805—year 1923) but there are variations in some details. For effective operation, the unit must receive the mixture with definite particles having a settling velocity. The units are not totally effective for flocculants or coagulated masses that may have a tendency to be buoyant. 

It is this ordering that gave the concept a theoretical bent as real separations are not ordered the retention times in most separation techniques appear almost random across a range of separation time. The mathematical definition of peak capacity, nc, for an isocratic separation is given as (Grushka, 1970)... 

This chapter examines another measure of the space used by 2D separations subject to correlation. Some researchers use the words, peak capacity, to express the maximum number of zones separable under specific experimental conditions, regardless of what fraction of the space is used. By definition, however, the peak capacity is the maximum number of separable zones in the entire space. No substantive reason exists to change this definition. The ability to use the space, however, depends on correlation. In deference to previous researchers (Liu et al., 1995 Gilar et al., 2005b), the author adopts the term, practical peak capacity, to describe the used space. The practical peak capacity is the peak capacity, when the separation mechanisms are orthogonal, but is less than the peak capacity when they are not. The subsequent discussion is based on practical peak capacity. 

The author anticipates that many readers will find the results reported here to be commonplace. If so, then why do we so often report the individual peak capacities of the two dimensions and their product as the 2D peak capacity One answer—the conservative one—is that the latter is indeed the maximum number of peaks that can be separated, in agreement with the definition. A more realistic answer is that it is easy to do and appears more impressive than it really is—especially to those who fund our work. In fact, as a practical metric it is often nonsense. Because orthogonality is so difficult to achieve, especially in 2DLC, the peak capacity is a measure of only instrumental potential, not of separation potential, and consideration of... 

Next, the case of m = n in Eq. (2.41), that is, the case that the number of components equals the number of imaginary equivolume partitioned regions, is considered. In this case, the denominator in Eq. (2.41) is log n and the formula coincides with the definition of the whole mixing capacity defined by Eq. (2.30). This is the point of contact between the multi-component mixedness and whole mixing capacity that is, both indices need not be discussed separately. 

For steady-state zones, where H and N also lack definition, we turned to the peak capacity as a common denominator for different methods. We have learned how to estimate peak capacity for ID separations we now extend this concept to incorporate two axes. For this we must reconsider the matter of spot dimensions when migration occurs along both axes rather than just one. 

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