BAGHOUSE 101 TRAINING Presented by: March 10, 2005

Baghouse 101 Outline Overview Design Fabric Types Shaker Baghouse Reverse Air Baghouse Pulse Jet Baghouse R & D

OVERVIEW

Why Do We Need A Baghouse Recover useable product Keep plant clean and workers safe Comply with state and federal regulations

Typical System Components Emission Source Pickup Points Ductwork Collection Equipment Baghouse Air Mover Fan

Types of Dust Collection SETTLING: dust settles on surfaces. CYCLONE: cyclone is utilized to capture larger particles ELECTROSTATIC PRECIPITATORS: positively charged particles become negatively charged for release. WET SCRUBBERS: mix water with dust, dust settles in a pond and is drawn back into the system. BAGHOUSES: dust collection method gathers dust on a piece of filter media and then it is removed from the material by air, or mechanical shaker.

Components of a Baghouse Hopper Housing Tubesheet Plenum

3 Types of Baghouses Shaker Baghouse Reverse Air Baghouse Pulse Jet Baghouse

Shaker Baghouse The first and oldest cleaning style Utilizes mechanically driven devices to “shake” the filter bag Particulate collects on the inside surface of the filter bag

Reverse Air Baghouse The second and next oldest cleaning style Utilizes a system of reversing air flow through the filter bag to create a “back washing” effect on the particulate, changing the filter bag surface contour, and releasing the collected particulate. Particulate collects on the inside surface of the filter bag

Pulse Jet Baghouse The third and newest cleaning style Differs drastically from both the shaker and reverse air baghouse Utilizes a powerful, short blast of compressed air in a reverse direction Particulate collects on the outside surface of the filter bag

BAGHOUSE DESIGN

Baghouse Design Inlet Velocity Can Velocity Inlet Grain Loading Inlet Temperature Outlet Emissions Inlet Grain Loading Air-to-cloth Ratio Differential Pressure (P) Fabric Selection and Efficiency

Inlet Grain Load 0.1 to 5.0 grains/ft3 = Light 6.0 to 15.0 grains/ft3 = Medium 16.0 to 30.0 grains/ft3 = Heavy 1.0 Grain = 1/7000 LB

Air-to-Cloth Ratio Shaker: 1.5:1 to 3.0:1 Reverse Air: 1.5:1 to 2.5:1 Pulsejet: 4.0:1 to 8.0:1

Differential Pressure Differential pressure (P) not to exceed 6” static pressure water gauge (S.P.W.G). Magnehelic gauge/manometer used for monitoring differential pressure Magnehelic gauge

Fabric Selection Operating temperature Abrasion resistance Collection efficiency Chemical make-up of gas stream Dust loading Air-to-cloth ratio Cleaning method

Air Flow Volume (CFM) Temperature Inlet velocity (3000 FPM or less) Can velocity (300 FPM or less)

Outlet Emissions Location dependent Application dependent Media dependent Regulatory impact

MEDIA TYPES

Media Types Natural Fibers Synthetic Fibers – Most Widely Used Cotton Wool Paper Synthetic Fibers – Most Widely Used Woven Felts

Fabric Selection Chart

Fabric Finishes

SHAKER BAGHOUSE

3 Basic Styles of Shaking Action Horizontal Shake Tube Shake Cradle Shake

Shaker Cleaning

REVERSE AIR BAGHOUSE

Components of a Reverse Baghouse

Reverse Air Cleaning Cycle Close the outlet or poppet damper Provide a period of “null” period to provide for settling of particulate Open reverse air poppet valve to allow reversed air flow to “backwash” through the fabric filters Close reverse air poppet valve, allowing a “null” period to all for settling of particulate Open outlet or poppet damper Compartment is brought back “on-line”

Reverse Air Cleaning

Points of Inspection Hanging structure Tensioning hardware Failure due to weight and elevated temperatures Chemical reaction will also deteriorate hanging hardware Filter caps may contain corrosion Clamps and fasteners usually cannot be used safely more than once

Points of Inspection Condition of thimbles Corrosion Particulate build-up Broken welds Cell plate for broken welds, corroded leakage Exterior door seals Biggest cause of compartment corrosion and collection efficiency

Points of Inspection Hopper evacuation equipment Hopper screws, rotary airlock valves, dump valves Magnehelic gauges. All lines should be cleared and cleaned before gauges are inspected Particulate removed from the hopper

Filter Bag Installation Cell plates should be carefully cleaned Thimbles should be brushed to remove particulate build-up Cell plates without thimbles should be carefully swept and holes brushed clean of particulate build-up

Filter Bag Installation (cont) Filter bags should be located in boxes, nearest the locations that they are to be installed. Beginning should be furthest from the compartment entry and furthest from any provided walkways Install hanging hardware prior to installing filters Attach filter bags at the top first, leaving the bottom of the filters to remain loose.

Filter Bag Installation (cont) Install bottom of filter bags Seams of each filter bag should face the walkway that serves that row of filters Check that seams are not twisted Tension filter bag

Installing Bag On Thimble STEP 1 STEP 2 STEP 3 INSTALL ONE SIDE OF BEADED CUFF OF BAG OVER THIMBLE BEAD INSTALL OTHER SIDE OF BEADED CUFF OF BAG OVER THIMBLE BEAD INSTALL CLAMP ABOVE BEADED CUFF OF BAG JUST UNDER THIMBLE BEAD IMPROPER IMPROPER IMPROPER

Proper Tensioning Typical Filter Bag Tension 5” diameter 35 lbs. 11.5” diameter 50 lbs. (Polyester) 11.5” diameter 75 lbs. (Fiberglass)

Tension Guidelines Excessive Tension: Results in high stress around ring covers and cuffs. Prevents the proper flexing needed to release the dust cake. Insufficient Tension: Results in bag to bag abrasion. Results in bag to structure abrasion. Inhibits flow of dust out of bag. Accelerates fatigue failures.

Operating Instructions for M-C Tensioning Tool Instruction SHEET

Daily Preventive Maintenance Walk through the baghouse area to check for normal or abnormal visual and audible conditions Check Differential Pressure Check the proper operation of the cleaning cycle Monitor the evacuation system Observe the stack for clean air particulate (opacity)

Weekly Preventive Maintenance Check poppet valves for proper operation Inspect fans/blowers for corrosion and vibration

Monthly Preventive Maintenance Clean the monitoring equipment lines Check the filter cleaning sequence to see that all poppit valves are seating properly Check all moving parts on the evacuation system Inspect inlet and outlet ducts for corrosion, leaks, and particulate build-up

Quarterly Preventative Maintenance Calibrate all monitors, particularly the outlet (opacity) monitors

Yearly Preventative Maintenance Inspect filter bags for leaks and holes Inspect compartments for particulate build-up Inspect hoppers for abrasion and corrosion Inspect door and port gasketing Inspect baghouse structural for corrosion

Start-Up Procedure Process air should be brought up gradually Pre-coating fabric filters can reduce initial particulate impact and help to prevent blinding during initial process air introduction Monitoring systems should be observed and noted

PULSE JET BAGHOUSE

Components of a Pulse Jet Baghouse

Pulse Jet Cleaning Cycle Uses compressed air from air compressors Cleaning pressures of 80 – 110 PSI Components Sequential timer Solenoid valve Diaphragm valve Air header Blowpipes

Cleaning Mechanism Air compressors are used to develop higher pressure air Air is distributed from the compressor storage tank to the baghouse “header” assembly via pipe plumbing Pulse valve is attached to each of the pulse tubes and connected to the compressed air source On command, pulse valves momentarily open and close, allowing a short blast of compressed air to enter the pulse tubes and be distributed to each filter served in that row by that pulse tube

Pulse Jet Cleaning

Clean on Demand vs. Continuous Cleaning Cleaning system is activated when differential pressure reaches high limit set point and deactivated when differential pressure reaches low limit set point. Always keeping a consistent dustcake Continuous Cleaning Cleans on a specific on-time and off-time

Points of Inspection Inspect cages for corrosion, damage, broken wires and areas that might abrade or cut filter surfaces Pulse tubes and nozzle openings for blockage and corrosion Venturis should be observed for uneven abrasion wear Flexible tube connectors inspected for cracks, holes and leaks

Points of Inspection Diaphragm valves and solenoid valves for proper operation Timer board inspected and tested for firing sequence and pulse duration Hopper door and plenum doors should be inspected for seal damage, wear and leaks

Points of Inspection Evacuation equipment inspected to be sure hopper is continually emptied as needed Tubesheet should be cleaned and inspected for corrosion and physical stress leaks Inspect manometer and clean lines Hoppers should be emptied completely and swept clean

Installation Procedure for Snapband Bag Step 1: Bend the snapband into a kidney shape. Place the grooved gasket into the tubesheet hole. Step 2: Move the snapband into place. A sharp popping noise should be noticed as the band is properly seated around the circumference of the tubesheet hole. Step 3: Check to make sure you cannot twist the snapband and that band is securely seated with the metal tubesheet fitted into the center of the band groove.

Installation Procedure for Bag and Cage Assembly

Installation of Top Removal Blowtubes

Daily Preventive Maintenance Walk through the baghouse area to check for normal or abnormal visual and audible condition Check Differential Pressure Check the proper operation of the cleaning cycle for both time between cycles and duration of cleaning cycle Check compressed air and water traps on clean, pulse air system- #1 reason for cleaning problem

Daily Preventive Maintenance Monitor the evacuation system Observe the stack for clean air particulate (opacity)

Weekly Preventive Maintenance Spot check for fabric filter leaks and holes

Monthly Preventive Maintenance Clean the monitoring equipment lines Check temperature indicating equipment Check the compressed air lines and operation of “dryer” if available

Quarterly Preventative Maintenance Perform a leak detection test Calibrate all monitors, particularly the outlet (opacity) monitors

Yearly Preventative Maintenance Inspect hopper and interior of compartments for corrosion and leaks Inspect all control valves and plumbing Inspect entire cleaning air system for moisture and corrosion contamination

What Not To Do When Installing Bags Do not open carton or remove bags until they are ready to install. Do not sit on, stand on, or walk on bags. Damage will occur that is not visible to the naked eye. Do not drag bags over catwalks, guard rails, thimbles, or any rough surface. Do not have hand tools or sharp instruments in pockets or pouches near bags. Do not pull on any loose threads. Do not stack cartons higher than five Do not install bags you have reason to believe will fail prematurely.

RESEARCH & DEVELOPMENT

Typical Fabric Tests Tensile Test Pounds/1” of width to pull apart. Air Permeability Test First Bubble Point Inches w.g. with Isopropyl alcohol  2.5 mean for paper Mullen Burst Test Approximately 90 (wet) psi for strong paper. MIT Flex Test