TITLE “Mixing Technology”

SPEAKER: Mr. Jan Siert Tjeerdsma

JOB TITLE: Sr. Project Manager

DATE : Antwerp, March 20th, 2013

WWW.STOCEXPO.COM

Content:

• Mixing Technology, sufficient turbulence and blending on demand.

• How to minimize downtime on mixers and what propellers can do.

SUBJECT

• Introduction

• Why Mixing ? – Laminar and Turbulent Flow

– Blending time & improvement of heat-transfer

– Mixer positioning

• Common mixer specifications – Mechanical design

– Propeller design

– Process innovation

• Summary

Introduction

• Jan Siert Tjeerdsma

• Bsc Chemical Engineering

• Project Engineer Jongia Mixing Technology

• 18 years experience with Major contractors

• Responsible for projects in Biofuels, Tank Storage farms, Petrochemical & Fine Chemicals

• Linkedin-profile

Mixer specification • Power calculation according API (conventional

method)

– Minimal required power:

Vessel volume * 0.00115 * C1 * C2 * C3

C1 = correction for Non Ideal Vessel

C2 = correction for Bulk viscosity

C3 = correction for difference in density

• Propeller to be installed through

mounting flange

(retractable through nozzle)

Laminar & Turbulent Flow

Laminar & Turbulent Mixing

• Reynolds < 2000 Laminar flow

• Reynolds 2000 – 3200 Transition region

• Reynolds >3200 Turbulent flow

• Reynolds in mixing depends on: – Liquid density

– Rotational speed of propeller

– Propeller Diameter

– Viscosity of the liquid

– Independent of propeller geometry

Flow in the tank

• Mixer produces a turbulent flow in propeller zone. (Viscosity < 1000 cP)

• Flow degrades from turbulent in propeller zone to laminar in tank

Why should we mix in a tank ? • Preventing settling of solids

• Homogenize temperature (Prevent stratification)

• Blending various fluids or fractions

• Prevent emission of volatile components

Why should we NOT? • High power consumption, useless?

• Risk of oilspill

• Maintenance required

• Cost aspect

Mixing methods

• Jet Mixing

– High power consumption compared to mechanical mixing

• Air mixing

– Emission of volatile components

Mixing methods

• Jet Mixing – Relatively long blending time, compared to

mechanical mixing

60 minutes 640 minutes

Mixing methods

• Side Entry Mixers

– Mixing element below liquid level

• Top Entry mixer

– Not always applicable due to floating roof, long shafts, price competitiveness

Blending time & Heat transfer

• Blending only takes place in turbulent zones

• The only real turbulent zone in the tank is the propeller area

• Blending depends on vessel content passes propeller zone

Blending time & Heat transfer

Heat dissipation through flow created by mixer

Blending time & Heat transfer The pump capacity / thrust of the mixer(s) determines the blending time Blending and support of heat transfer are identical

Blending time

• Important to specify required blending

• Relation between blending time and power is quadratic

• Blending time is based upon completely topped-up vessel

• Positioning of mixer has a major influence on blend time

• Flow of impeller determines blend time

Position Mixer(s)

Flow Impeller

• Flow = Nq * n (1/sec) * D^3

• Nq depends on propeller geometry (blade angle & projected area)

• n = rotational speed of propeller

• D = diameter of propeller

Flow vs. Required power • RPM reduction by 2 Flow reduces by 2

• To compensate loss of flow; increase propeller by 2^1/3

• Result : power consumption drops

Example, different propellers at equal flow:

Power consumption with propeller 600 mm at 430 rpm = 42,22 kW

Power consumption with propeller 755 mm at 215 rpm = 16,68 kW

Conventional design • Is this your tank farm??

And this your Mixer ?

Consider

• Reliable product

• High efficient thrust

• Easy to maintain

• Versatile commodity parts applied

• Compact and Modular design

• Developed for relability

• The Jongia Sydmikser RWM range!

Marine Propeller design , based on best practice and many years of experience

7 Degree angle for optimal position wallmount

Standard IEC motor sizes, optional explotion proof, PTC’s, etc

Heavy duty bearings, dismountable at full tank

DIN , ANSI or other flange sizes available

100% polycarbonate Belt drive Cover.

Tank Shut –Off device, even with full tank!

Jongia Sydmikser

“Shut-off Device “ enables maintenance on mixer during full tank mode

Mechanical Seal according to DIN standards or alternaitive configurations

Air Vent, to prevent Dry-running of sealfaces

WWW.STOCEXPO.COM

See for yourself

It is at our booth # F1

Get your free brochure

Get your Sydmikser RWM from

Jongia Mixing Technology!!

Thank you!