Mechanism for granulometric distribution of solid particles

A mechanism for the granulometric distribution of solid particles being loaded into a vessel of relatively large dimensions, such as a process reactor, blast furnace, silo, incinerator, dryer, etc., from equipment of small dimensions in relation to the vessel, includes a feed hopper which has an outlet opening that can be variably positioned within the mechanism to introduce the solid particles into a chamber located above the uppermost ends of a plurality of concentric, inclined, preferably conical or pyramidal surfaces. The latter define respective generally downwardly directed free flow paths for the particles to conduct them to a lower location where they enter the upper ends of a corresponding plurality of concentric sets of descending tubes. The discharge ends of the tubes where they feed into the vessel being charged are disposed in a symmetric array. The entire arrangement is such that, during the loading operation, the particles form a continuous bed of solids from the location where they accumulate in the space above the inclined plates to the location where they leave the descending tubes and accumulate in the vessel, so that the formation of "valleys" in the surface of the bed in the vessel and consequent segregation of the particles in the bed are effectively minimized.

This invention relates to a mechanism for charging large vessels, such as 
process reactors, dryers, incinerators, blast-furnaces, silos, etc., with 
solid particles from equipment of small dimensions in comparison with said 
large vessels. More particularly, the present invention relates to such 
mechanism which will effect the charging operation in either a continuous 
or an intermittent way, but in any event substantially uniformly in order 
to avoid segregation of the particles which can occur due to heterogeneity 
of the dimensions of said particles. The invention further relates to such 
mechanism which, when necessary, as in the case of blast-furnaces, enables 
the particles to be directed to previously determined regions of the 
vessel being charged. In general, the present invention renders it 
possible to obtain a dependable control over the granulometric 
distribution of the particles during the charging operation. 
At the present state of the art, it is well known that, in processes which 
involve the granulometry of solid particles, said particles are not simply 
allowed to fall down at random to the interior of the vessel into which 
they are being charged. It is necessary to provide means to give them a 
certain orientation to avoid irregularities on the surface of the bed of 
solids. Heretofore, those skilled in the art have been particularly 
interested in keeping the surface of the bed flat. However, when heat 
transfer or contact between solids and gases are involved, granulometry 
has proved to be a very important factor to be observed due to 
irregularities which could occur in the process if the particles were not 
properly arranged in the bed. Thus, the basic purpose of the present 
invention is to provide a mechanism enabling a well-controlled 
distribution of the particles according to their granulometry to be 
achieved, though it is also a purpose of the invention to provide a 
mechanism capable of working as a loading equipment. 
The invention herein disclosed is the result of improvements introduced in 
the equipment as described in Brazilian patent application No. PI-7805842 
(owned by the assignee of the present invention) in order to avoid some 
difficulties that have been encountered when the principles of the 
equipment of the referred application were employed in large volume 
receptacles. 
The basic principle of the invention described in Brazilian application No. 
PI-7805842 is to permit the solid particles to flow downward, from a 
rotating hopper over a conical or pyramidal surface whereon said particles 
slip to a plate provided with a row of holes and thence into the upper 
regions of a number of descending tubes that are in communicaton with said 
holes, thus forming the path for the descending particles to the interior 
of the vessel in a uniform arrangement. For better understanding, an 
example of a geometric model of an embodiment of said invention is given. 
Thus, in the equipment of Brazilian application No. PI-7805842, an inclined 
plane on which the solid particles slip is represented by a cone. The 
plate provided with holes, to which the descending tubes are attached, 
would be represented as a narrow brim fixed around the base of said cone. 
The assembly of said cone and the narrow brim at its base is enclosed and 
protected by a plate formed in the shape of a frustum of a cone, the lower 
rim of said frustum being welded to the outside circumference of the rim. 
Thus, it is easy to understand that the solids falling on the conical 
surface will be invariably guided to the bottom plate whence they will 
flow through the holes to the descending tubes. 
According to the same line of thought (analogy with a geometric model), it 
can be seen that the present invention shows several new aspects in 
respect to that disclosed in the aforesaid Brazilian application No. 
PI-7805842. 
(a) Instead of the solids (which come from a rotatory hopper) falling over 
the external surface of a single cone or pyramid, they are divided into 
two parts, each part flowing on a respective one of two conical or 
pyramidal concentric surfaces. 
(b) Instead of a single line of holes on the bottom plate which envelops 
the lower rim of the conical surface (as shown in Brazilian application 
No. PI-7805842), the present invention includes two lines of holes each at 
the bottom of a respective conical surface which permits a greater number 
of descending tubes in the same surface area because two ring plates are 
provided at the base of the two conical surfaces. 
(c) Since there are more descending tubes in the equipment of the present 
invention than in that disclosed in Brazilian application No. PI-7805842, 
for the same available space, it is possible to obtain a distribution of 
the lower ends of the tubes according to a more compact model than in the 
prior equipment. 
It is well known by those skilled in the art that the minimum diameter of a 
tube in a multitubular arrangement of a loading equipment is a function of 
the granulometry of the particles that are being loaded. This happens 
because, if the cross-section available for the solids to flow into is 
small in respect to the diameter of the particles, there will be problems 
due to the building up of static agglomerates known as "bridges" or 
"cages," which, in common parlance, is called "clogging." In the current 
practice, said tube diameter cannot be smaller than three times the 
particle diameter. On the other hand, if the cross-section of the tube 
available for the flowing of the solids is extremely large in respect to 
the diameter of the particles, segregation is liable to occur inside of 
the tube and, accordingly, in the loading points. 
It is evident that knowledge of these facts is the result of scientific 
research on problems regarding the flow of solids. Some factors, like the 
case of the diameter of the particles being larger than that of the tubes 
or the case of free fall of the particles without any interaction among 
them, are not considered. 
Another factor that must be observed when conveying solid particles by 
means of multitubular loaders is the interval among the tubes on the 
loading site, i.e. the distribution of the lower extremities of the tubes 
which end in the interior of the vessel to which the solids are being 
conveyed. If the lower extremity of each tube is quite far apart from that 
of the next tube, the bed of solids immediately under the extremities of 
said tubes will not present an even arrangement. The space comprised among 
several open extremities immediately under the plane formed by the said 
lower tube extremities to a certain distance downwardly in a vertical 
direction (said distance being a function of the distance from one 
extremity to the next one), will remain empty due to a phenomenon well 
known by those skilled in the art as the formation of "valleys." More 
specifically, such "valleys" are voids in the bed which are formed because 
of a tendency of the granulated solids to accumulate in conic piles. When 
said solid particles flow continuously, there is a tendency for these 
cones not to be formed due to the conjoining of them at their bases; 
instead, there is a tendency of the bed to become compact. However, such 
ideal arrangement of the solid particles in vertical flow is never 
obtained (expecially if the flow is continuous) because the lower 
extremities of the loading tubes are always somewhat spaced apart from 
each other. Thus, the formation of "cones," even if highly minimized, is 
almost impossible to avoid and "valleys" will always be present. 
From what was said above, it is clearly understood that the more distant 
the lower extremity of one tube (through which the particles flow to the 
interior of the vessel) is positioned in relation to that of the next 
tube, the larger is the width of the associated "valley". As each "valley" 
is formed by the side surface of the "cones" formed by the solids, it is 
easily understood that, when a "valley" has a very large width, it 
corresponds to "cones" of great dimensions and that will provide 
conditions for the particles to slide freely on such cone surfaces, thus 
causing an unavoidable segregation of the large particles from the small 
diameter particles (fines). It is one of the objectives of the present 
invention, if not to eliminate the formation of "valleys," at least to 
minimize the appearing of said "valleys" in such a manner that, with the 
"cones" having only a small slope and a little "height," the sliding of 
the solids and consequent segregation are not so likely. Thus, the solids 
bed, from the top of the mechanism to the bottom of the large vessel where 
the solids are being accumulated, functions as an agglomerate which flows 
with a uniform flow through its entire height. 
As it was decribed above, according to the scheme of the invention 
disclosed in Brazilian application No. PI-7805842, the middle part of the 
loading mechanism includes a limited area which envelops the base of a 
cone or a pyramid, being on said limited area attached to a series of 
descending tubes which lead the flow of solids to an area defined by the 
cross-section of the body of the vessel following a very compact pattern 
of distribution of the lowest extremeties of said tubes. In other words, 
as it has been seen that the solid particles, before reaching the interior 
of the vessel, are forced to flow on an inclined surface, the upper 
apertures of the loading tubes were adapted to holes at the bottom of said 
inclined surface. The downwad direction of each of said tubes is 
conveniently deviated in each case to provide a compact arrangement of the 
lower ends of the tubes in the interior of the vessel. 
Depending on the size of the particles which will define the diameter of 
the loading tubes for a certain cross-section of the vessel to the 
interior of which solid particles are being loaded, the scheme of the 
prior equipment has proved to be completely efficient. However, when it is 
necessary to design a vessel to work with great quantities of solids (the 
specifications for the size of the solids and consequently the diametere 
of the tubes being kept unchanged), the number of tubes required may be so 
large that even only one line of holes disposed in an arrangement around 
the base of the cone or pyramid, would require exceedingly large 
dimensions for said cone or pyramid to include all the tubes. The problem 
may become so serious that, for a given cross-section of the vessel, if a 
great number of descending tubes is necessary (for the technical 
principles of Brazilian application No. PI-7805842 to be followed), the 
dimensions of said cone or pyramid would be disproportionately large in 
comparison with the dimensions of said vessel and the descending tubes 
would be exceedingly long in order to compensate for the inclination 
necessary to position the lower extremeties of said tubes in the loading 
area. On the other hand, many problems would arise in regard to the 
stability of the assembly, unnecessary material would be spent to make the 
equipment and, principally, the basic scope of the invention would not be 
fulfilled, because, instead of a large vessel being charged by means of a 
small equipment, the loading equipment would be larger than the vessel. 
Another obstacle that must be overcome is the unnecessary length of the 
tubes, because an increase in the time of flow of solids inside the tubes 
(especially if they are inclined) would provide conditions for segregation 
instead of avoiding it. 
Another difficulty that may arise with the disproportional increase in the 
size of the cone or pyramid on whose surface the solids have to slide, is 
the increase in the time of residence of the solids during all stages of 
the process, which would mean a loss in efficiency of the 
antisegregational effect. 
Thus, for certain conditions of granulometry of the particles and size of 
the vessel, the invention disclosed in Brazilian application No. 
PI-7805842 would be satisfactory, but in cases like those just described 
above (say, great dimensions of the equipment) changes in the scheme of 
the invention become necessary in order to avoid the above-mentioned 
problems. This is the basis on which the mechanism of the present 
invention was conceived. dr 
The foregoing and other objects, characteristics and advantages of the 
present invention will be more clearly understood from the following 
detailed description thereof when read in conjunction with the 
accompanying drawings, in which: 
FIG. 1 is a diagrammatic illustration of the mechanism according to the 
present invention, in vertical section; 
FIGS. 2, 3, 4 and 5 are cross-sectional views, on greatly enlarged scales, 
taken along the lines O-O, A-A, B-B and C-C, respectively, in FIG. 1; 
FIGS. 6, 7 and 8 are fragmentary diagrammatic illustrations, in vertical 
section, of the upper part of the mechanism of FIG. 1 and show certain 
variants thereof according to the present invention; 
FIGS. 9 and 10 are schematic representations of regions of the mechanism of 
the present invention to aid in the discussion of the functioning of the 
mechanism; and 
FIGS. 11 to 14 are graphs of data taken from actual granulometric analyses 
and workings of the mechanism of the present invention.

Referring now to the drawings, and especially to FIGS. 1 to 8, in greater 
detail, it is seen from FIG. 1 that the mechanism of the present invention 
has, over its vertical extent, four distinct regions denoted I, II, III 
and IV. 
Region I comprises a hollow cylinder 1 provided with a lid 2, said lid 
being provided with a plurality of charging holes or openings 2a through 
which solid particles are introduced from outside by means of any suitable 
device. 
A funnel shaped hopper 3, which in its lower extremity is provided with a 
discharge opening or hole 8 through which said solid particles flow 
downwardly, is positioned under the loading holes 2a. This funnel shaped 
hopper 3 is attached to a shaft 6 supported in a bearing 7 and impelled to 
a slow circular motion by means of a motor 4 connected to said shaft 6 by 
means of a reduction gear 5. 
Region II presents, as an outstanding feature, a space for the solids to 
flow freely, such space being defined by conical surfaces which direct 
said solids to region III. More specifically, there are three conical 
surfaces: one is an inner surface that is formed by the cone 10; the 
second one is an intermediate surface 12 that is constituted by a metallic 
plate formed in the shape of a frustum open at its top and making an 
envelope to the central cone 10; and the third one is the inner surface of 
the external wall 9 surrounding the entire region II of the equipment. 
Said conical surfaces thus form two compartments for the solid particles 
to flow through: the compartment 16 between the inside face of the 
external wall 9 and the outside face of the intermediate conical surface 
12, and the compartment 17 between the inside face of the conical surface 
12 and the outside face of the cone 10. 
The top of the cone 10 extends upward into the region I by means of a small 
diameter cylinder 18 that is situated precisely under the lower extremity 
of the shaft 6. The cylinder 18 terminates substantially at or slightly 
above the level of the opening 8 in the bottom of the rotary funnel shaped 
hopper 3, thus providing the compartment 19 defined in the cylinder 1 with 
the shape of an annular ring in cross-section (see also FIG. 2) in which 
the free surface of the bed of solids is formed. 
As shown in FIG. 1 (in a lengthwise cross-section), the conical plate 12 at 
its top opens upwardly by means of a rim 11. From FIG. 2 (which shows the 
cross-section O-O) and FIG. 3 (which shows the cross-section A-A) it is 
seen, therefore, that by means of its relative position the rim 11 acts as 
a flow divider. 
In FIG. 2 the relative position of the loer opening 8 of the rotating 
hopper 3 in relation to said rim 11 can be seen, as also the relative 
position of the cylinder 18 that is an extension of the cone 10. According 
to FIG. 2, the free surface of the solids accumulated in the compartment 
19, after having entered the compartment when the discharge opening 8 of 
the hopper 3 is centered (as indicated by the dot-dash circle in FIG. 2) 
in the annular space surrounding the inner cone cylinder extension 18, 
will have an angle of rest whose vertex will coincide, i.e. be in 
substantial vertical alignment, with the rim 11, as can best be seen in 
FIG. 6. Thus the solids slide uniformly on each of the inclined surfaces, 
thereby causing an homogeneous granulometric distribution in each of the 
two compartments 16 and 17. 
There are two other possible ways of positioning the discharge opening or 
hole 8 of the funnelled hopper 3 in respect to the rim 11 of the open 
conical plate 12: 
(a) On the one hand, as shown in FIG. 7, the opening 8 may be closer to the 
internal face of the wall 1a of the cylinder 1 in the region I in such a 
way that, as the mass of solid particles accumulates in the compartment 
19, its free surface has a funnel-like shape according to which 
arrangement the uppermost portion of said surface is closely adjacent to 
the cylinder wall and the lowermost portion, i.e. the bottom of the 
funnel-like surface, is closely adjacent to the central cylinder 18. 
(b) On the other hand, as shown in FIG. 8, the opening 8 may be positioned 
closer to the periphery of the extension cyclinder 18, which causes the 
solid particles to accumulate so as to form a conical pile the top of 
which is situated closely adjacent to the cylinder 18 and the lower limit 
of which is closely adjacent to the external wall 1a. 
In case (a), the solid particles which fall from the opening 8 of the 
rotating hopper 3 slide over the inclined surface of the bed in the 
compartment 19 in such way that the large particles tend to accumulate 
close to the cylinder 18 and the small particles gather close to the 
internal face of the wall 1a which envelops the region I. As the bed of 
solids flows downward to the interior of the mechanism, therefore, coarser 
particles concentrate in the compartment 17 from where they pass through 
the inner ones of the descending tubes 13 within the region III to the 
central zone of the vessel 15 defined in the region IV. The smaller 
particles tend to flow to the compartment 16 and then, after passing 
through the outer ones of the descending tubes 13, accumulate in the 
peripheral zone of the vessel 15. 
In case (b), the result is exactly the contrary of what happens in case 
(a). Thus, the coarser particles, which again gravitate to the lower 
region of the conical mass of particles, now adjacent the wall 1a, flow to 
the compartment 16 and then, from there, to the peripheral zone of the 
vessel 15, while the fine particles enter the compartment 17 and flow from 
there to the central zone of the vessel 15. 
In both cases (a) and (b), an oriented segregation is achieved. If, 
instead, the center of the opening 8 of the funnel shaped hopper 3 is 
aligned with the top of the circular rim 11 of the upwardly open conical 
plate 12, then the loading of the vessel is effected without segregation, 
i.e. in all internal zones of the vessel 15 located in region IV, the same 
granulometry is achieved as existed in the material prior to loading, this 
being obtained because of the unique characteristics of design of the 
mechanism described in the present invention. 
As can be seen from FIG. 1, the presence of the two concentric conical 
regions 16 and 17 is the characteristic which enables one, as shown in 
cross-setion in FIGS. 4 and 5, to include in the same circular area a 
larger number of descending tubes 13 of a given diameter, specifically 
because said tubes 13 are arranged in two concentric circular rings. This 
advantage, which is peculiar to the present invention, enables the 
formation of "valleys" to be minimized through the more compact 
distribution of the outlet openings 13a (FIG. 1) at the lower extremities 
of the tubes 13 in the interior of the vessel 15 (region IV) that can be 
achieved, and, consequently, also leads to a reduction of the additional 
segregation problems at this step of the loading. 
It is important to note that the number of descending tubes 13 which is 
disclosed herein for use in the mechanism of the present invention (as 
shown in FIGS. 1, 4 and 5) is limited to 22, but it should be realized 
that this number has been given just to simplify the understanding of the 
invention and that the number may be, for any given case, the largest that 
can be included in a given area. In the present application it was deemed 
advisable not to present a very large number of tubes 13 in the drawings, 
in order not to render them very complex without contributing to the 
understanding of the scope of the invention. 
The descending tubes 13 in the region III undergo changes in direction when 
passing from the scheme of FIG. 4, where they are identified as tubes 1B 
to 22B, to that of FIG. 5, where they are identified as 1C to 22C. This is 
clearly seen, because from the level of the lower end of the concentric 
conical compartments 16 and 17, in which said tubes 13 are distributed in 
two concentric circular rings (see FIG. 4), the tubes 13 change to a more 
homogeneous distribution (see FIG. 5) at the level of discharge into the 
interior of the vessel 15 (region IV). This rearrangement is accomplished 
because some inclination is applied to some tubes, as clearly shown in 
FIG. 1. 
Insofar as the general operation of the mechanism of the present invention 
is concerned, it is to be noted that an automatic level control CN (see 
FIG. 1) is provided which operates according to sensors equipped with 
photoelectric cells, gamma rays or any sensible radiation therein provided 
which senses the loading of the chamber 19, stopping the admission of feed 
from the outside in order to avoid blocking the rotary movement of the 
funnel shaped hopper 3 whenever the level of solids in the region I 
reaches a critical maximum value. 
It is deemed advisable to add that the examples given herein of cylindrical 
and conical surfaces have been presented only in order to make the 
conception of the present invention easily understood, but they are by no 
means limiting factors of this invention. The same principles as those 
described herein, can be applied to pyramidal and prismatic surfaces whose 
cross-sections may be triangles, squares, hexagons, etc. The only 
important aspects that have to be maintained in all cases are the 
rotational system of loading, the inclination of the surfaces on which the 
solid particles slip, the presence of two concentric inclined surfaces, 
the relative positioning of the funnel-shaped hopper, the downward 
distribution of the loading tubes, and the level control. 
To provide a practical demonstration of efficiency of the mechanism therein 
described in the loading of fragmented solids, there are presented in the 
following description some average values taken from granulometric 
analysis of samples of material obtained from vertical vessels loaded with 
the hereinbefore referred to equipment in continuous operation. Of the two 
tables set forth below, Table I presents data from a vessel loaded without 
the employment of the mechanism described in this invention, solid 
particles being dropped at random due to the action of gravity forces. 
Table II, on the other hand, presents data obtained from the same vessel, 
but this time it was loaded by means of the mechanism herein described 
fitted to promote a granulometric distribution without segregation of the 
size of particles in the bed. 
The regions of the vessel from which samples are taken are schematically 
outlined as two concentric cylinders in FIG. 9 (the outer cylinder is 
denoted Region 1 and the inner one Region 2, in each case over its entire 
length) just to give an idea of the positioning of the points of sampling 
when said samples are taken radially or in depth. It is important to bear 
in mind, however, that the sampling points denoted A, B and C in the 
sketch for each region are not intended to be exactly located; rather they 
are shown only to make clear that the samples are taken from different 
levels. Furthermore, each point does not represent a specific "sample"; it 
is rather the average of several samples taken from a level approximately 
indicated by the arrow. Accordingly, the numbers set forth in the tables 
are averages of many values obtained in several levels in the same region. 
Region 1, as sketched in FIG. 9, includes the peripheral zone of the bed 
which represents 63.6% of the total volume of solid particles loaded. 
Numbers in the tables are the percentages in weight of each size of 
particle found in the granulometric analysis of the solids sampled in the 
various levels of the two concentric regions of the vessel. More 
precisely, each number represents the average of several values for each 
level in the same region. 
The ranges for the size of particles are limited by preestablished values, 
so that granulometric ranges of particle diameters between 5.08 cm and 
2.54 cm, between 2.54 and 1.90 cm, and under 1.90 cm are covered. 
TABLE I 
______________________________________ 
% of Solid Particles 
from 5.08 from 2.54 under weight 
to 2.54cm to 1.90cm 1.90cm of sample 
(coarse) (medium) (fine) kg 
______________________________________ 
Feed 56.27 13.07 30.66 1320 
Region 1 
61.28 13.08 25.64 840 
Region 2 
47.03 13.11 38.96 420 
______________________________________ 
TABLE II 
______________________________________ 
% of Solid Particles 
from 5.08 from 2.54 under weight 
to 2.54cm to 1.90cm 1.90cm of sample 
(coarse) (medium) (fine) kg 
______________________________________ 
Feed 32.37 15.68 51.95 1100 
Region 1 
32.50 15.68 52.22 700 
Region 2 
32.28 15.90 51.82 400 
______________________________________ 
From an examination of Table I it can be seen that, without the use of the 
mechanism of the present invention, a significant segregation occurs in 
the two concentric regions. The peripheral region (Region 1) presents a 
high concentration of particles with diameter larger than 2.54 cm when 
compared with the central region (Region 2). On the other hand, particles 
with diameter smaller than 1.90 cm are concentrated in the central region 
(Region 2). 
From an examination of Table II, on the other hand, it is seen that when 
using the equipment of the present invention with the funnel-shaped hopper 
3 positioned in such a manner that the center of its bottom opening 8 
coincides with the line formed by the rim 11 on top of the conically 
shaped plate 12, a loading without segregation is achieved, since the 
granulometric analysis of the particulate solids after the loading (in the 
two concentric regions) presents almost no alteration in respect to the 
granulometric analysis of the original feed. 
FIG. 10 shows a sketch of a cross-section of the vessel 15 where the 
numerals 24 and 25 represent circumferences of specific regions within the 
outer boundary, denoted 23, of the vessel, the relative positions of these 
various regions to the center of the vessel, here denoted 26, defining the 
zones from which the samples were taken. 
Data from granulometric analysis of said samples, after some mathematical 
treatment that will be more fully described presently, are plotted on 
graphs as shown in FIGS. 11, 12, 13 and 14 which give a clear view of the 
loading of a bed free from segregation. 
Reference is now made to FIG. 10 in greater detail. Taking the distance 
from the central point 26 to the outer wall 23 of the vessel as the basis 
for reference, the distances from the circumferences 24 and 25 to the 
center 26 will be referred to in terms of the relation between the said 
distances and the distance from the center 26 to the outer wall 23 of the 
vessel. Evidently, therefore, in any case, the respective relations will 
always be less than 1.00, which defines the precise point of sampling. 
Circumference 24 represents a sampling region at a certain distance from 
the center 26 in such a manner that the quotient obtained by dividing said 
distance by the total radius is 0.808, which defines the sampling points 
Q, R, M and V. 
Circumference 25 represents a sampling region where the quotient obtained 
by dividing the distance from the circumference 25 to the center 26 by the 
total radius of the vessel, is equal to 0.467. The said circumference 25 
defines the sampling points N, P, S and T. 
Only to keep a certain discipline in the systematics used and to provide 
that the data are typical of well localized sampling points, a series of 
samplings were made in the north-south direction, which corresponds to the 
points R, S, T and V on said circumferences 24 and 25, the pair of points 
R and S on the one hand and the pair of points T and V on the other being 
located, respectively, in the north and in the south regions of the 
cross-section, approximately on the points determined by the intersections 
of the north-south diameter (vertical in FIG. 10) with said 
circumferences. Another group of samples was taken from locations on the 
east-west diameter, specifically the points M, N P and Q where said 
diameter (horizontal in FIG. 10) crosses the circumferences 24 and 25 in 
the east and west regions of the cross-section. 
This choice was taken to make sure that cross-section was scanned according 
to two well representative directions in the bed of solids. Data are the 
average of samplings performed at several levels and are referred to 
specific particle sizes taken from granulometric analyses. 
The "gauges" which define the medium size of the particles are numbers 
referred to the greatest diameter of each granulometry range. This 
definition is given only as a conventional reference to make the results 
easier to understand. 
Table III below gives the correspondence between "gauges" and granulometry 
ranges. 
TABLE III 
______________________________________ 
Granulometric Range Particle Diameter 
larger than 
smaller than 
gauge (in mm) (in mm) 
______________________________________ 
6.35 -- 6.35 
12.70 6.35 12.70 
19.05 12.70 19.05 
25.40 19.05 25.40 
38.10 25.40 38.10 
50.80 38.10 50.80 
______________________________________ 
The experiments were conducted in the following sequence: 
1. Granulometric analyses were performed with the solid particles of the 
feed before dropping them into the vessel, thus obtaining the percentage 
of solids included under each "gauge" of solids in the mixture. 
2. The solid particles were then loaded into the vessel without using the 
anti-segregational mechanism of the present invention, and a new set of 
data were obtained from granulometric analysis. 
3. Finally, the percentage of solids of each "gauge" obtained after loading 
was divided by the percentage of solids of the same "gauge" in the 
original feed before loading. 
In the case that no segregation is found to have occurred during the 
loading operation, the relation obtained pursuant to item 3 above is a 
quotient equal to 1.00. 
If segregation does occur, the quotient will be: 
(a) greater than 1.00 when the percentage of solid particles of a given 
average size ("gauge") after the loading, is greater than the percentage 
of the particles of the same size in the original feed; 
(b) less than 1.00 when the percentage of solid particles of a certain size 
after being loaded into the vessel, is smaller than the percentage of the 
same size of particle before loading. 
It will be clearly understood that, when the quotient is greater than 1.00 
with respect to the samples of a certain region of the bed, values smaller 
than 1.00 will be found for other regions. This is a consequence of the 
migration of particles in the bed and is further evidence that segregation 
occurred. 
4. The vessel was charged employing the anti-segragational mechanism of the 
present invention and granulometric data from the solids, taken from the 
referred sampling points, were obtained. 
5. The percentage of solid particles of each "gauge" was obtained by 
following the procedure described in item 3 above, i.e. dividing th 
post-loading percentage values obtained pursuant to item 4 by the 
pre-loading percentages obtained pursuant to item 1. 
In this case too, quotients near or at 1.00 represent little or no 
segregation, while quotients greater or less than 1.00 show that 
segregation occurred. 
Said data were plotted on graphs as shown in FIGS. 11, 12, 13 and 14. On 
said graphs the sampling points designated by the above-mentioned letters, 
are plotted on the abscissas at the quotients corresponding to the 
respective ratios of (a) the distance from the sampling point to the 
center point to (b) the total radius, and the quotients of the 
granulometric relations for each "gauge" of solid particles are plotted on 
the ordinates. Finally, the points in the graph corresponding to each 
particle size are united by straight lines, forming in each case an 
irregular line which represents the profile of the arrangement of the data 
for each particle size distribution. It will be apparent that the more 
obtuse the angles formed by the sections of any given irregular line, the 
more the profile of that line will be "flat" and close to the horizontal 
(which corresponds to the quotient 1.00). 
To sum up, the graph of FIG. 11 refers to a loading operation in which the 
mechanism of the present invention was not employed and the samples were 
taken on the north-south direction, while FIG. 12 is the graph of an 
operation similar to that represented by FIG. 11 but in which samples were 
taken on the east-west direction. In contrast thereto, FIG. 13 presents 
the graph which results from an operation in which the anti-segregation 
mechanism of the present invention was employed, the direction of the 
sampling procedure being north-south, and FIG. 14 is the graph prepared 
with data obtained when the anti-segregational mechanism of the present 
invention was employed but the direction of sampling was east-west. Thus 
it will be evident that when the present invention was utilized, almost no 
segregation occurred during the loading operation. 
As previously stated, the present invention is applicable to use with a 
variety of different industrial processes. Merely by way of examle, the 
vessels into which the particles are being charged may be blast furnaces 
employed for the reduction of ores to metals by reaction with coke. Again, 
the solids being processed may be particles of bituminous shale, and the 
vessels into which they are charged may be pyrolysis vertical retorts in 
the interiors of which the shale particles flow downwardly forming a 
moving bed which is heated by contact in counter-current with upwardly 
flowing hot gases. Other examples of like or different operations will 
readily suggest themselves to those skilled in the art. 
Generally speaking, therefore, the present invention can be seen to provide 
a mechanisn for granulometric distribution of solid particles which is 
specially designed to provide the loading of such solid particles into 
large dimension vessels starting from equipment of small dimensions in 
relation to said vessels, the mechanism being characterized by the 
presence of the following features: 
means (3) which can be variably positioned to introduce disaggregated solid 
materials into the mechanism; 
means, constituted of a plurality of inclined concentric surfaces (10, 12) 
positioned under an outlet opening (8) of the introducing means (3), for 
providing for a free flowing of the disaggregated solid materials along a 
plurality of paths from the region of their introduction into the 
mechanism to a lower location; and 
means for conducting the disaggregated solid materials away from the said 
lower location, this last-named means comprising a corresponding plurality 
of concentric closed lines of downwardly inclined tubes (13) under the 
region where the inclined surfaces are located, with each of the lines of 
tubes communicating with the respective one of the flow paths defined by 
the inclined surfaces, and the tubes being provided with a symmetric 
arrangement of their lower extremities in the region where the tubes open 
to the interior of the associated vessel (15); 
the inclined surfaces and the descending tubes being constructed and 
arranged such that, during the loading operation, the disaggregated solid 
materials form a continuous bed from the location where they fall from the 
introducing means (3) to the location where they leave the descending 
tubes (13) and accumulate in the interior of the associated vessel (15). 
It will be understood that the foregoing description of preferred 
embodiments of the present invention is for purposes of illustration only, 
and that the various structural and operational features herein disclosed 
are susceptible to a number of modifications and changes none of which 
entails any departure from the spirit and scope of the present invention 
as defind in the hereto appended claims.