magra high-rate thickener presentation 2011

7/18/2019 Magra High-Rate Thickener Presentation 2011

http://slidepdf.com/reader/full/magra-high-rate-thickener-presentation-2011 1/5

CLARIFICATION

REACTOR

THE CONCEPT

THE MAGRA HIGH-RATE THICKENER

WAS DEVELOPED TO FULFILL THE ROLE OF A

THICKENER, REACTOR AND CLARIFIER

THE ADVANTAGES

MOST AFFORDABLE & VERSATILE HIGH-RATE

THICKENER ON THE MARKET

BEST PERFORMANCE PER UNIT AREA AND

SMALLEST FOOTPRINT OF ANY THICKENER

THICKENING COMBINED WITH CLARIFICATION

NO MOVING PARTS

MINIMAL MAINTENANCE AND LOWEST

OPERATING COST OF ALL THICKENERS

QUICK RESPONSE AND LITTLE RESIDENCE

TIME WITH ZERO LOCK-UP

PATENT PROTECTED

THICKENING

PASTE WITHOUT PAIN

ASTE WITHOUT PAIN

MAGRA HIGH PERFORAN E

MAGRA HIGH PERFORAN E

THI KENER/REA TOR/ LARIFIERHI KENER/REA TOR/ LARIFIER



THE DESIGN

1. CYLINDRICAL CONICAL TANK TO MAINTAIN

HIGH-RATE THICKENING, PURE OVERFLOW CLARITY AND HIGH UNDERFLOW DENSITY

. FEED PIPE CULMINATING IN !BULLHORNS"

FOR REDUCED DISCHARGE VELOCITY

#. SLOPED HEIGHT AD$USTABLE OVERFLOW

LAUNDER PROVIDES SELF CLEANING

%. MIING CHAMBER DESIGNED FOR NON

DESRUCTIVE,THOROUGH SLURRY ANDFLOCCULANT MIING

'. CENTRAL DEWATERING PIPE & COLLECTOR

CONE FOR INTERNAL DILUTION CYCLE

(. CONICAL BAFFLE TO SUSPEND FLOC BED

AND PROVIDE AN INCLINED SURFACE FOR

CONSOLIDATION

) CONSOLIDATION CONE FOR EFFICIENT

AND RAPID DEWATERING

*. DRAW OFF BO DESIGNED FOR SUSTAINED

UNDERFLOW WITHDRAWAL AND EASE OF

MAINTENANCE

1

2

3

4

5

6

7

8



HOW IT COMES TOGETHER + LOW DENSITY FEED

A suspension of solid particles in the carrier liquid at low

density enters the mixing chamer and mixes with the

flocculant! "he mixing chamer extends down to the

free settling #one! "he downward $elocity of the

suspension suddenly decreases passing from the

mixing chamer %small diameter& to the thic'ener tan'

%larger diameter&!

"he sudden decrease in the downward $elocity allows the

large particles to settle out!

"he small particles are carried upward and accelerate

through the annular throat creating turulence and

collisions! "he settling $elocity of the fines particles

increases as the particles grow larger! "he upward flow$elocity ao$e the throat decreases until the top of the

conical affle is reached! (hen the settling $elocity of

the particles exceeds the upward $elocity) the particles

start to drop downwards and on its downward path

collisions occur with upward mo$ing particles! "his

causes agglomeration and the particles finally ecome

large and hea$y enough to drop ac' through the

annular throat into the free settling #one! "he fines

particles form a floc ed which act as a filter and a

clarified #one is formed ao$e the floc ed! *larified

liquid o$erflows into the o$erflow launder!

"he fines particles dropping down from the floc ed mixes

with the feed exiting from the mixing chamer di$erted

y the collector cone! *oagulation of fines now ta'es

place and fewer fines are carried upward through the

throat! "his increases the capacity of the +agra

"hic'ener far eyond any other 'nown unit!

FLOW DIAGRAM FORLOW DENSITY FEED



"he passage of solids particles exiting the mixing

chamer and annular throat are intercepted

y the inclined surfaces of the consolidation

cone! *onsolidation ta'es place and the

particles slide or roll down the inclined

surfaces! ,iquid separating the solids is

displaced and collects elow the collector

cone! -ome liquid returns to the free settling

#one resulting in continuous dilution of thefree settling #one leading to faster settling of

solids particles!

,iquid collected under the collector cone mo$e up

the dewatering pipe! .pward mo$ement of the

liquid in the dewatering pipe is caused y the

difference in pressure at position 1 %liquid

pressure& and position 2 %pressure due to

liquid #one ao$e floc ed plus floc eddensity and feed density&! "he liquid in the

dewatering pipe contains unspent flocculant

which o$erflows into the mixing chamer and

therey acts to dilute and flocculate the feed!

A continuous internal dilution cycle is

created! /ilution further reduces flocculant

consumption and settling rate is increased!

/ensity increases with consolidation andcompaction due to the inter0granular contact

pressure etween the particles! "he depth of

the compaction #one can e used to control

the underflow density! (ith an increase in

height) the residence time increases and

together with the additional pressure eing

exerted on the compaction #one allows for

liquid to escape from the compaction #one

therey further increasing the density! FLOW DIAGRAM FORLOW DENSITY FEED



HIGH DENSITY FEED + UP TO '' SOLIDS

UNDERFLOW DENSITY + UP TO )#,

SOLIDS

A suspension of solids particles in the carrier

liquid at high density enters the mixingchamer and mixes with the flocculant!

ecause of the high density of the

suspension there will e a le$el displacement

in the mixing chamer! "he top edge of the

mixing chamer is modified to include 0

notches similar in shape to the o$erflow

launder 0notches! A portion of the o$erflow

is di$erted into the mixing chamer!

A second internal dilution cycle is now created

with an increase in the upward flow $elocity!

+uch less dewatering is required at high feed

density compared with low feed density to

otain the same underflow density! ncreasing

the up flow $elocity to the pre$ious low

density condition will not affect the operation

or the o$erflow clarity!

"he thic'ener again operates li'e a low feed

density unit! locculant consumption is at the

same le$el as a low feed density unit!

"he +agra igh0ate "hic'ener is self regulatory

and oth the internal dewatering cycles

adust automatically to accommodate feed

conditions and pro$ide for reliale operation! FLOW DIAGRAM FORHIGH FEED DENSITY

magra high-rate thickener presentation 2011

Documents