Got there at 17:15 on Wednesday 22nd May 2024.
I seem to have started on doing the calculations in "Wills" on about
the 24th of April. On-and-off - has been a backdrop to the time,
doing these calculations following the "Examples" in Wills' book.
Having
cover-to-cover
'ed the Wills' "Mineral Processing Technology" by 09 April 2024.
Going through "Examples" to end of Chapter 3.
So that's been 2 months and 1 day since the book arrived.
So topics covered:
Chapter 1
Chapter 3
The point and driving-force?
These are generalities in minerals processing.
Subsequent Chapters in the book are specific processes used in mineral
processing - eg comminution; froth-flotation; etc.
Applying analysis of these generalities I show
An example from Chapter 3 : slurries (finely ground ore in water -
otherwise known as "pulps"):
initially a "brain-buster" for me - in Example 3.5 (in 8th
Edition) which is the second slurries Example - where this time there
is a volume flow-rate of slurry, yet the slurry is described by a
mass % solids. Volume<=>mass...
The most valuable approach is to develop a "model" in your mind which is
easy to recall and from which you could re-derive the maths if you
come back to the same situation again some distant time later. Given
some archane equation alone is hard to remember.
Sketching, I came up with a model of a "Unit mass of slurry" (so in
SI-units that would be 1 kg) which has a "corresponding volume" -
which can now have a % solids and a % liquids...
You have converted to working in volumes - which is useful given the
flow-rate of the slurry is given as a volume per unit time...
For what it's worth - given this may be incomprehensible.
This is my text-file of notes and developing the calculations.
The maths is expressed in Lisp (the "emacs Lisp" of the text-processor
I use), with the answer generated by the text-editor's interpretter
interpretting that expression "inserted" into the text.
Anything to the right-hand-side of a ";" is disregarded by the
interpretter.
Stream 1 5 m^3 hour^-1; 40% solids by mass
Stream 2 3.4 m^3 hour^-1; 55% solids by mass
Density of solids = quartz : 3000 kg m^-3
Density of liquid - assume is water at 1000 kg m^-3
Tonnage of dry solids (equivalent) pumped per hour?
E3.5
====
Stream 1 :
Unit mass
1 ---
liq.|
|
__|__
solid| 0.4
|
0 ---
goes to a "corresponding volume to unit mass"
which is an entire volume conceptually comprising a volume of solid
and a volume of liquids.
rho_w = 1e3
rho_m = 3e3
Water component
V_c-v_l =
(/ (- 1 0.4) 1e3) ;; 0.0006
Solid component
V_c-v_m =
(/ 0.4 3e3) ;; 0.00013333333333333334
Corresponding volume
V_c-v =
(+ (/ (- 1 0.4) 1e3) (/ 0.4 3e3)) ;; 0.0007333333333333332
(* (+ (/ (- 1 0.4) 1e3) (/ 0.4 3e3)) 1e3) ;; 0.7333333333333333 ;; Litres
Stream 1 slurry has 0.733L per kg mass
Density of the slurry 1
becomes accessible
(/
1e0 ;; kg ;; unit mass
(+ (/ (- 1 0.4) 1e3) (/ 0.4 3e3))
) ;; 1363.6363636363637 ;; kg m^-3
rho_sl_1 = 1363.6363636363637
--------------------------------
Stream 2 :
1 ---
liq.|
__|__
| 0.55
solid|
|
0 ---
Water component
V_c-v_l =
(/ (- 1 0.55) 1e3) ;; 0.00044999999999999993 ;; m^3
Solid component
V_c-v_m =
(/ 0.55 3e3) ;; 0.00018333333333333334 ;; m^3
Corresponding volume
V_c-v =
(+ (/ (- 1 0.55) 1e3) (/ 0.55 3e3)) ;; 0.0006333333333333333
0.633L per kg of slurry
Density of slurry 2
(/ 1e0 (+ (/ (- 1 0.55) 1e3) (/ 0.55 3e3))) ;; 1578.9473684210527 ;; kg m^-3
rho_sl_2 = 1578.9473684210527
--------------------------------
With the slurry densities, now going to what is being pumped - the
combined streams...
v-dot = 5
rho_sl_1 = 1363.6363636363637
f_m_min_1 = 0.4
v-dot = 3.4
rho_sl_2 = 1578.9473684210527
f_m_min_2 = 0.55
(+ ;; the two streams
;; stream1
(*
5 ;; m^3 h_1
1363.6363636363637 ;; kg m^-3
;; ;; 6818.181818181819 ;; kg h^-1
0.4 ;; f_m_solids
) ;; 2727.272727272728
;; stream2
(*
3.4 ;; m^3 h-1
1578.9473684210527 ;; kg m^-3
;; ;; 5368.421052631579 kg h^-1
0.55 ;; f_m_solid
) ;; 2952.631578947369
) ;; 5679.904306220096 ;; kg h^-1 of solids pumped
5.7 Tonnes h^-1 of solids in pumped stream(s).
My answer agrees with Wills, but uses different expressions - mine are
derived from my "unit mass => corresponding volume" model
(R. Smith, 23May2024, 25May2024 (eds), 10Jun2024 (ed. diag1st))