Rotary Press Revolutionizes Sludge Compaction Presented by: Ross - - PowerPoint PPT Presentation

Rotary Press Revolutionizes Sludge Compaction

Presented by:

Ross Elliot VP & GM Tecumseth Filtration Inc.

Rotary Press Introduction

• Waste sludge dewatering issues
• Pulp and Paper mill sludge categories
• Mechanical dewatering methods
• Rotary press system design overview
• Rotary press benefit analysis
• Preliminary performance results
• Summary

Sludge Management Issues

• Final % Solids

– Difference between cake and slumping sludge – Handling issue if it does not pile easily – Transport water or solids - economics

• Solids Capture Rate and Filtrate Clarity
• Operator Activity
• Maintenance and Support
• Energy Consumption
• Raw Water Usage

Sludge Management Issues

• Final % Solids
• Solids Capture Rate and Filtrate Clarity

– High capture rate versus throughput efficiency – Clear filtrate means less ‘dead-load’ in wwtp

• Operator Activity
• Maintenance and Support
• Energy Consumption
• Raw Water Usage

Sludge Management Issues

• Final % Solids
• Solids Capture Rate and Filtrate Clarity
• Operator Activity

– Manpower should focus on revenue generation – Requires equipment that accepts variable input – Equipment and area cleanup should not be required

• Maintenance and Support
• Energy Consumption
• Raw Water Usage

Sludge Management Issues

• Final % Solids
• Solids Capture Rate and Filtrate Clarity
• Operator Activity
• Maintenance and Support

– Total Cost of Ownership is a big issue – labor, parts – Rotating parts wear, belts need to be changed – Downtime expense and impact on process – Ongoing chemical usage – polymers, wash-up

• Energy Consumption
• Raw Water Usage

Sludge Management Issues

• Final % Solids
• Solids Capture Rate and Filtrate Clarity
• Operator Activity
• Maintenance and Support
• Energy Consumption

– Moving parts have drive motors, the higher the speed the greater the energy required

• Raw Water Usage

– Wash-up, flushing, cleanliness

Pulp and Paper Sludge

Four types of WWTP residuals in P&P:

• Primary sludge

40%

• Secondary or waste activated

1%

• Combined primary and secondary

54%

• Dredged sludge

5%

• Key issue is the presence of fiber

Types of Mechanical Dewatering

• Typical to have a thickener prior to dewatering
• Belt press – most common
• Screw press – added after belt press or standalone
• Centrifuge – not commonly used in pulp & paper

because of fiber filtration characteristics; high speed rotation requiring large motors

• Rotary press – new application

Belt Press Dewatering

• Many designs and evolutions, requires pre-thickening
• Stages – gravity filtration, medium pressure between belts,

higher pressure between nip(s)

• Susceptible to variation in feed; cleanliness issues; poor

capture rate

Screw Press Dewatering

• Wide variation in designs and concepts
• Screw moves sludge through perforated shell or

screen to thicken then dewater

Rotary Press Dewatering

• Technology transfer from municipal WWT industry
• Flocculation chamber followed by drainage, pressing

and restriction zones

System Animation

Rotary Press Animation

Rotary Press System

6-Channel Rotary Press System

Rotary Press Examples

Operating Parameter Adjustments

• Inlet sludge pressure
• Rotation speed of the filter
• Outlet restriction pressure on bellows
• Polymer dosage

Impact on Performance

• Throughput
• Cake solids
• Filtrate clarity

>50% Solids >98% Capture Rate

Example Results – Breakey Fibres

• Deink pulp producer – installed system trials
• Sludge contains 40-50% ash

Operator Procedures

Start-up

• Check to ensure gap is restricted
• Start filter drive, start sludge & polymer pumps
• Watch until cake is produced

Shutdown

• Stop feed pumps
• Watch until no cake is produced, stop filter drive
• Knock remaining cake out with prod – cleanup done

Maintenance Requirements

Change Interval(hr) Time(hr)/channel Gear box oil 4000 0.5 Scraper blades 7000 0.5 Deflector liner 7000 0.5 Shroud seals 15,000 Filter disks 65,000 3.5

Energy Usage

• Slow rotation speed of disks (0.2 to 2 rpm) requires
• nly small drive motors

– 1-channel unit has 5 hp (3.7 KW) motor – 6-channel unit has 20 hp (15 kW) motor

• Installed 6-channel unit uses about 6.65 kWh/dry ton
• Polymer mixer has a 1 hp motor

Economic Benefit Summary

• Energy – low operating consumption
• Maintenance – reduced time &parts; fewer outages
• Operations – reduced attention while in operation;

reduced cleaning

• Solids – higher solids reduces handling and disposal
• Chemicals – lower coagulant/flocculant usage

Lab Sample Testing – OCC Linerboard

Projected Installation Results

• Linerboard mill projected results from sample tests

Summary of 2014 YTD Sample Testing

Site Pilot Testing

• Following sample testing, a site test is the next step
• Two channel types, complete lab, sludge & polymer tanks

Rotary Press Summary

• Improved technology for dewatering mill sludge
• Designed for:

– Low power usage – Low maintenance and upkeep – Low operator attention and support – Minimal polymer usage – Low water usage – 5 minute/day internal shower cleaning

• Completely automated with alarming
• Quiet, clean and odor free

Thank you! Ross Elliot ross@tecumseth.com