langley separation & process belt press 101 operational ......2 sludge inlet dewatered sludge...

Langley Separation & Process Belt Press 101

Operational Training

Applying 40-Years of Experience and Process Knowledge

Belt Press 101

2

sludge inlet

dewatered

sludge outlet

wedging

roll

mixer upper belt

washing system

lower belt

washing system

upper belt

centering system

lower belt

centering system

lower belt

Tensioning

system

upper belt

tensioning

system

Belt Press Side View

July 2018 LS&P BFP Operational Training 101

• Process

• Mechanics

LS&P BFP Operational Training 101 3

Dewatering Fundamentals Belt Press 101

July 2018

• Flocculation / Conditioning

• Gravity zone

• Low pressure

• High pressure


Process Components Belt Press 101

July 2018

Filtration Zones


Gravity

L

Wedge

High Pressure

Linear Pressure

Belt Press 101

July 2018

Colloidal Particles


+ +

+ +

+ +

+

+

+ +

+ +

+ +

+

+

• Most of the particles we must remove have a negative charge.

• Shells of cationic charges form around the particles.

• The force of repulsion between the particles is stronger than the force of gravity.

• As a result the particles stay in suspension.

Belt Press 101

July 2018

Flocculation


Suspended Solids

Polymer

Floc

-

- -

- -

-

-

-

+ +

+ +

+

+ +

+ +

+

+

+

+ +

+

+

Belt Press 101

July 2018

How Polymers Work


The primary mechanism is electrostatic attraction Attractions between positive and negative charges Analogous to magnetic attraction

Belt Press 101

July 2018

Types of Water in a Biological Suspension


Cell walls

Intra cellular water

Free water

Cohesive Water

Belt Press 101

July 2018

• Venturi Effect

• Mechanical

• Combined


Conditioning Systems Belt Press 101

July 2018


Belt Press 101

• Polymer injection

• Mixing o Static

o Mechanical

• Detention time

Conditioning

July 2018

• Static o Zero detention time

o Sensitive to changes in velocity and viscosity

o Increase head loss

o Reduced effectiveness >2%

o Inexpensive


Mixing Devices Belt Press 101

• Mechanical

July 2018

Venturi Effect


Velocity Gradient

Laminar Flow Turbulent Flow

Polymer

Belt Press 101

July 2018

BPF WR Sludge Mixer


Outlet

HIGH ENERGY

LOW ENERGY

Inlet

Belt Press 101

Outlet

Gearbox

Agitator

July 2018


Venturi Effect Process Schematic

Polymer Feed Pump

Sludge Feed Pump

Belt Filter Press

Mixing Valve

Dilution Water

Belt Press 101

July 2018


Mechanical / Combined Mixing Process Schematic

Belt Filter Press

Dilution Water

Belt Press 101

Polymer Feed Pump

Sludge Feed Pump

July 2018

IDEAL MIXING SCHEME


Mix Tank

Venturi Mixer

SLUDGE

POLYMER

Belt Press 101

POLYMER

July 2018


Belt Press 101

July 2018

• Distribution

• Drainage o Plows

o Support grids


Gravity Zone Function Belt Press 101

July 2018

LS&P BFP Operational Training 101

20

sludge inlet

dewatered

sludge outlet

wedging

roll

mixer upper belt

washing system

lower belt

washing system

upper belt

centering system

lower belt

centering system

lower belt

Tensioning

system

upper belt

tensioning

system


July 2018

Belt Press Top View


sludge inlet

mixer

lower belt

tensioning

system

upper belt

tensioning

system

Shower Cleaning

Handwheels

Belt Press 101

July 2018

Gravity Zone Nomenclature


Running Direction

Support Grid

Belt

Headbox

Plow (raised for cleaning)

Plow (engaged)

Belt Press 101

July 2018

Gravity Zone


Gravity Area (ft2) = L x W

Gravity

Gravity Zone Inlet

Low Pressure Zone Inlet

W

Sludge – Belt Contact Area

L

Belt Press 101

July 2018


WATER DRAINING

ZONE

Belt Press 101

Thickening Plows Series Arrangement

July 2018

• Provide a transitional pressure o >Atmospheric ~ 0.0

o <1st high pressure roller- 1.5 PSI


Low Pressure / Wedge Function Belt Press 101

July 2018

Rolling Radial Wedge


1-2 in. .

1st pressure

roll

0.2- 1.5 PSI

2.0- 3.5 PSI

Belt Press 101

July 2018

LS&P BFP Operational Training 101

27

sludge inlet

dewatered

sludge outlet

wedging

roll

mixer upper belt

washing system

lower belt

washing system

upper belt

centering system

lower belt

centering system

lower belt

Tensioning

system

upper belt

tensioning

system


July 2018

Perforated Roller


Belt Press 101

July 2018

High Pressure Filtration Area


1

Area = (2 x Ri x x (i / 360) x W) i = 1

n

Ri

i

Roll

W Sludge - Belt

Contact Area

Roller

Belt Press 101

July 2018

• Linear o Expressed as PLI ( pounds / linear inch)

• Area o Expressed as PSIG


Pressure Belt Press 101

July 2018

Calculating Area Pressure


r1

i i = <180o

r1

T1=50

T2=50

Pa= T1

r1

50

5 = 10 PSI

10”

Belt Press 101

July 2018

• Converts linear tension (PLI) to area pressure (PSI)

• Shearing forces are created as a result of differential in tangential belt speed


High Pressure Objectives Belt Press 101

July 2018


Shearing Force Belt Press 101

July 2018

Shearing Forces


= S 1 +S 2 +S 3 .......S 10

R 1 = 1205 mm

R 2 = R 1 + Sludge thickness

Felt

sludge

Displacement

R 1

R 2

Belt Press 101

Felt

July 2018

Conventional Pressure Section

0

2

4

6

8

10

G W S1 S2 S3 S4 S5 S5 S6 S7 S8

PS

I

Rollers LS&P BFP Operational Training 101 35

36

24

18

14

12

10

10

Belt Press 101

July 2018

Optimum Pressure


F F F F

Belt Press 101

July 2018

Excessive Pressure


F F F F

Belt Press 101

July 2018


Belt Press 101

July 2018

Performance Relationships


Belt Press 101

July 2018

Feed Solids Vs. Cake


15

17,5

20

22,5

25

27,5

30

32,5

35

1,00 2,00 3,00 4,00 5,00 6,00 7,00 8,00

Feed solids [%]

Cak

e d

ryn

es

s [

%]

ANAEROBIC DIGESTED SLUDGE

Belt Press 101

July 2018

Polymer Vs. Volatile Solids


0

5

10

15

20

25

30

35

30,00 35,00 40,00 45,00 50,00 55,00 60,00 65,00 70,00

Po

lye

lectr

oly

te d

osin

g [lb

s/t

on

]

Volatile solids [% on TS]

Belt Press 101

July 2018

Volatile % Vs. Cake Solids


15

17,5

20

22,5

25

27,5

30

32,5

35

30,00 35,00 40,00 45,00 50,00 55,00 60,00 65,00 70,00

Cake

dry

ne

ss [%

]

Volatile solids [% on TS]

Belt Press 101

July 2018

10.00

15.00

20.00

25.00

30.00

35.00

40.00

0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00

TSS %

Cake %


Anaerobic %Cake Solids vs %TSS Belt Press 101

July 2018

High Solids Machines


Municipal waste sludge (TSS = 4% ; VS= 65%)

0,00

2,00

4,00

6,00

8,00

10,00

12,00

14,00

16,00 gra

vity

wedge

1°

roll

2°

roll

3°

roll

4°

roll

5°

roll

6°

roll

7°

roll

8°

roll

9°

roll

10°

roll

11°

roll

12°

roll

13°

roll

14°

roll

15°

roll

Pressure zone

Su

rfa

ce

pre

ssu

re [p

si]

0,00

5,00

10,00

15,00

20,00

25,00

30,00

35,00

Dry

ne

ss [

%]

Torque

Dryness

Belt Pressure

Belt Press 101

July 2018

Modular configuration


WR 5: working zones

WR5

WR7

WR 5: working zones

WR9

WR11

WR 5: working zones

WR 5: working zones

WR13

WR15

BELT WIDTH (M): 1.2 – 1.6 – 2.0 – 2.5 – 3.0

Belt Press 101

July 2018

• Wrap angles greater than 180 o Increase filtration area

o Decrease area pressure


Wrap Angle vs. Area Pressure Belt Press 101

July 2018

• Throughput

• Cake solids

• Polymer dosage

• Capture

• Belt speed

• Pressure


Performance Relationships Belt Press 101

July 2018

• Polymer dosage

• Detention time / belt speed

• High pressure filtration area

• Area pressure

• Cake stability


Factors Affecting Cake Solids Belt Press 101

July 2018

Area Pressure Vs. Cake Solids

15%

17%

19%

21%

23%

25%

7 8 9 10 11

Solids

• Diminishing returns

• Reduced capture %

• Reduced belt life


Belt Press 101

July 2018

Polymer Vs Cake Solids

• Dependent upon: o Operator attention

o Solids variance

o Bandwidth

0%

5%

10%

15%

20%

25%

30%

10 12 13 14 15 18

lbs / ton

Ca

ke


Belt Press 101

July 2018


Factors Affecting Polymer Dosage Belt Press 101

• Dynamic o Cascade effect

o Detention

o Mixing energy

o Media impact

• Static o Feed suspended solids

o Dissolved solids

o Volatile solids concentration

o Zeta potential

July 2018

Throughput Terminology


Input

Filtrate Loss

Output

Belt Press 101

July 2018

• General method o Input

• The belt press equation o Output

• Mass balance

• Hydraulic loading vs. Solids loading


Calculating Throughput Belt Press 101

July 2018

General Input Calculation


• Q = flow rate (gpm)

• Ts = % concentration (TSS)

• Sg = specific gravity

Throughput = Q *Sg* Ts * 500.4

Belt Press 101

July 2018

The Belt Press Equation

55

• W = cake width (in)

• T = cake thickness (in)

• V = belt speed (fpm)

• Cs = cake solids (%)

• Sg = specific gravity

• K = 0.26

Throughput = W x T x V x Cs x Sg x K

Belt Press 101

LS&P BFP Operational Training 101 July 2018

• Capture o Polymer Dosage

o Fabric Weave / Permeability

o Proper Throughput

o Pressure

56

Factors Affecting Throughput & Capture % Belt Press 101

• Throughput o Belt speed

o Cake solids

o Effective belt width

o Cake thickness

o Specific gravity


• CAUTION WHEN CLEANING MACHINE!

• NEVER stand on side beams when operating

• NEVER place hands inside operating machine

• Verify Function of Tag Lines

• NEVER WORK ON ACTIVE MACHINE!

57

Safety Considerations Belt Press 101


Contact Langley Separation and Process

1405 Pecan Circle

Canyon Lake, Texas 78133

Main: 512-662-9917

Cell: 817-269-8388

Email: [email protected]

Web: www.langleyseparation.com

58

Questions or Comments Belt Press 101


mailto:[email protected]

http://langleyseparation.com/

langley separation & process belt press 101 operational ......2 sludge inlet dewatered sludge...

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