Presentation of Pulse Jet Fabric Filter FabriClean TM General FF schematic layout Pulse Jet Fabric Filter FabriClean TM May 7, 2010 1 Edition EMB Rev 13
FabriClean UniClean PulseClean FabriClean Side entry with gas/dust distribution Down flow in bag zone Split into compartments Designed for use of long bags (6-8 m) Used in power boilers, mineral industry, waste incineration etc. Low pressure cleaning Semi compartment offline cleaning UniClean Bottom entry to compartments Up flow in bag zone Big pre-seperation effect incorporated Act as one compartment Designed for use of bags up to approx. 4.5 m For processes with high dust load or where on-line maintenance is not required PulseClean Bottom entry to compartments Up flow in bag zone Split into compartments Designed for use of bags up to approx 4.5 m Used in the mineral industry, waste incineration etc. Semi compartment offline cleaning Pulse Jet Fabric Filter FabriClean TM May 7, 2010 2
Highlights Modest space requirements Unique gas/dust distribution system Modern control system to control cleaning Auxiliary equipment Designed to meet the most stringent emission requirement Designed to accommodate long life time of filter media Low steel weight Easy maintenance Pulse Jet Fabric Filter FabriClean TM May 7, 2010 3
General layout The FF consists of a number of groups Cleaning principle (Needle Felt Bag & Glass Bag) Control system Construction Highlights Site photos FF types References Weather enclosure Top box Outlet damper Access Outlet duct Inlet duct Casing Gas distribution Inlet damper Dust removal systems Insulation Support Hopper Bags and cages Pulse Jet Fabric Filter FabriClean TM May 7, 2010 4 to front page
Details of gas/dust distribution 7 Outlet damper Outlet duct 1 6 Inlet duct 2 4 5 8 Inlet damper 9 Guide vane Distribution screen 3 1 Gas inlet ( 15-18 m/sec) 2 Inlet to compartment 3 Dust extraction Pulse Jet Fabric Filter FabriClean TM May 7, 2010 5 4 Gas is distributed and goes through distribution screen 5 Dust down flow between bags 6 Clean side of filter 7 Gas outlet 8 Collected dust 9 Dust drop out
Gas/dust distribution Dust laden gas enters the inlet duct from the process equipment and flows through the inlet damper into the individual compartments containing the filter bags. The gas velocity is lowered significantly in the gas distribution chamber, therefore a big part of the dust will drop out directly into the hopper reducing the dust burden on the filter bags. The direction in the gas distribution chamber is upward and baffle plates ensure a uniform flow across the distribution screen. Clean gas outlet Distribution screen Type T Collected dust Distribution screen (Shown schematic) Baffle plate (One of more options) Dust drop out Dust plane Guide vanes Raw gas with dust inlet Pulse Jet Fabric Filter FabriClean TM May 7, 2010 6 Distribution screen (Shown schematic) Distribution types Dust drop out to previous
Gas distribution Types Type T Type L Type I Pulse Jet Fabric Filter FabriClean TM May 7, 2010 7 to previous
Cleaning principle Needle Felt Bag Bag cleaning phase Venturi Tube sheet Filtration phase Clean gas outlet Filter cake Raw gas with dust Clean gas outlet Primary purge air Secondary purge air Tube sheet Dust fallout Purge air 250 Filter bag Cage 12 pieces Filter bag Cage Pulse Jet Fabric Filter FabriClean TM May 7, 2010 8 Unique function Glass Bag
Cleaning principle Glass Bag Bag cleaning phase Venturi Tube sheet Filtration phase Clean gas outlet Filter cake Raw gas with dust Clean gas outlet Primary purge air Secondary purge air Tube sheet Dust fallout Purge air 150 Filter bag Cage 16 pieces Filter bag Cage Pulse Jet Fabric Filter FabriClean TM May 7, 2010 9 Unique function Needle Felt Bag
Bags Each filter bag incorporates a stainless steel snap ring sewn into the top of the bag which, when fitted, locates securely in the tube sheet effecting a seal. A B C D E F G Installation Typical bag material Temperature limits o C Bags pre-erected with cages Up to 8 m bag design 10 Snap ring Correct bag/cage fit is Essential for long bag life A: PTFE needle felt B: PPS needle felt C: Wowen glass with e-ptfe membrane D: Polyimide needle felt E: Polyester needle felt F: m-aramid needle felt G: Pan 125 Cages to Cleaning princp. 260 190 260 240 150 200
Cages To support the fabric of the bag a mild steel wire (or stainless steel) cage is provided. The cage is designed to support the fabric evenly and restrict flexing and abrasion of the filter bag whilst allowing optimum dust release at the time of cleaning. The cage will be without joints as standard, but can be offered with a split joint if required. Each cage consists of 10 to 16 vertical wires, depending of the choice of the fabric, evenly spaced about its circumference which are, in turn, attached to horizontal bracing rings placed at appropriate intervals along its length. Venturis Divided cages Cages with venturis Different styles of surface protection are available. (Epoxi, galvanising) Cage for Glass Bag Cage for Needle Felt Bag A feature of each cage is a venturi, a spun section, located at the top of the cage, designed to enhance the pulse cleaning of the filter bag. 11 Cages up to 10 m bag design Bags to Cleaning princp.
Top box Tube sheet Tube sheet Venturi Cage 170 mm Filter bags Filter wall Minimum 4 mm thickness Stiffened to reduce distortion Precision cut holes Mild or stainless steel Tube sheet 175 mm 127 or 150 mm 175 mm 12 to Cleaning princp.
Casing The complete filter casing will normally be fabricated from 5 mm mild steel, stiffened internally and externally by rolled steel sections and tubes to withstand the gas pressure, wind loads and the earthquake zone if required. Top box Single type Division wall Parallel type Outlet duct Inlet duct Side panel 13 Gable panel Support beam
Top box Assembly Diaphragm valve Compressed air manifold Lifting eye Insulation lid Top box lid Soft glass fibre gasket Purge tubes Tube sheet Venturis Designed for efficient thermal insulation to prevent corrosion in the top box. Top box types 14 Tob box examples
Top box Types Single type Double type Outlet damper Outlet damper Pulse Jet Fabric Filter FabriClean TM May 7, 2010 15 to Top box assembly
Top box Compressed air manifold Air actuated diaphragm valves The compressed air manifolds for each compartment will be fitted with 1 pressure switch (CE marked if required) to monitor the correct performance of the diaphragm valves. When the diaphragm valves are activated the pressure in the compressed air manifolds is detected to identify that the valve open and closes correctly. The signals from the compressed air pressure switches are wired into the local filter controller. Quality proprietary valves used 38 mm minimum size Easily accessed and maintained 16 to top box assembly
Top box Top boxes during construction 17 to top box assembly
Top box Purge tubes Purge tube Purge tube easy on/off slip on connection Each purge tube has nozzles in the form of small holes positioned concentrically over the venturi of each cage/bag assembly. 18 to top box assembly
Hopper Pyramid type Hoppers with air heated area Level indicator Inspection hatch Bottom with heated area (Optional) Insulation Pneumatic hammer (Optional) Thermo sensor Hammering edge Air heated area Heating element 19 Longitudinal hopper
Hopper Longitudinal type Hopper with heating area Bottom with heated area (Optional) Insulation Inspection hatch Level indicator Hammering edge or Pneumatic hammer (Optional) Heating element Air heated area 20 Pyramid hopper
Weather enclosure If the filter is located outdoor a weather enclosure is often provided to facilitate good conditions for inspection and replacing of the filter bags. The enclosure can be offered either designed for use of single piece cages or split cages. Axial fan is also offered to ventilate the weather enclosure. Hoist 21 Natural ventilation
Dampers Outlet dampers with three blades Double inlet damper Mechanical safety lock Limit switch Pneumatic actuator Pneumatic actuator Mechanical safety lock NB:The damper leak rate is less than 1 % 22
Control system Modern proven control system Parallel or serial communication to plant control system Profi bus or mode bus are preferred. Communication to field components either parallel or serial. Operator panel can be located either in weather enclosure or in electrical room. Associated process plant can be controlled if required Communication with plant control systems if required Compressed air manifold pressure Valve operation Compartment emission Filter control system Plant control system Filter pressure drop Auxiliary equipment (Dampers etc.) 23 Measurements
Control system Filter control system Measurement Result 1) Filter p between inlet & outlet manifold Optimized air consumption, filter p and minimum wear of bags 2) Compressed air manifold pressure Check of correct valve operation and compressed air Detection supply Result 1) Dust content in clean gas and next row Able to detect and locate bag failure to be cleaned (optional) 2) Damper position (open/closed) Information regarding which compartments are in operation Plant control system Measurement/Detection Result 1) Hopper level indicator Warning/Alarm in case of high level 2) Hopper temperature (optional) Avoid condensation in hopper by control of heating Compressed air manifold pressure Inlet Outlet p Expansion of the control system to include more options is possible 24 to previous
Supports To enable unrestrained heat expansion of the FF, a number of possibilities are available, depending on customer requirements or local plant conditions Spherical bearing with Teflon covered steel plate Slide bearing FF Direction of motion Roller bearing FF Spherical top Pendular support FF Fixed point Direction of motion Concrete or steel Guide ring Spherical top (To be cut away after erection) Guide ring Spherical top Concrete Foundation bolt 25 Examples
Supports Rigid support FF Roller or slide bearing FF Combined pendular and rigid support Pendular support 26 to previous
Typical dust removal options Chamber Chamber Chamber Chamber Chamber Chamber Hopper Hopper Hopper Hopper Hopper Chamber Chamber Chamber Chamber Chamber Chamber Hopper Hopper Hopper Hopper Hopper Screw conveyor Drag chain Air lock Slide gate 27
Dust removal equipment Drive station FF hopper Drag chain Turning station) Turning roller) Screw conveyor FF hopper Slide gate Air lock Drive station Air lock Traction wheel (Lubricated intermediate bearing) 28 Installation examples to removal options
Dust removal equipment Slide gate Motion detector Air lock Air lock Drag chain, drive station Drag chain, turning station Screw conveyor 29 to removal options
Construction Alternative methods A fabric filter can be mounted in various ways: Mounting on site of minor units; some premounting takes place on ground level (please see the previous slides) Mounting on site of major units; the units have been pre-mounted in the manufacturing workshop Mounting on site of the complete fabric filter on ground level, and later lifting into position by crane Mounting of very big units in manufacturing workshop or other suitable place, transport to site by truck, and lifting into place by crane The solution that proves to be optimal for the customer under the circumstances, financially as well as practically, will be selected economically. Samples of pre-construction methods 30
100 o 20 Access facilities Dimensioned for loads: Walks. Evenly distributed 3 kn/m2 Walks. Single load 3 kn within 100x100mm Railings. Horizontal 0.4 kn/m Stairway angle. 370-450 Standard DIN Materials. Mild steel 260 ~41 0 ESP roof ESP side wall 800 500 500 230 200 500 700 1100 1100 500 550 230 200 Max 9000 6000 2400 800 Tube 48.3 x3.2 Tube 26.9 x 2.6 Grate 30x30x3 Min 2200 Max 3000 Platform Staircase tower 3600 800 31 Example
Access facilities Stair tower Dimensioned for loads: Walks. Evenly distributed 3 kn/m2 Walks. Single load 3 kn within 100x100mm Railings. Horizontal 0.4 kn/m Standard DIN 32 to previous
Insulation An important factor for the function and life of the fabric filter is an efficient heat-insulation. To avoid condensation with consequent corrosion and reduced lifetime as well as to avoid uncontrolled heat expansion and deformation, the total surface of the precipitator is insulated carefully with mineral wool from 100 to 200 mm thick. The insulation is to be covered, taking into account the heat expansion of the FF, with appropriate sheeting. Hopper isolation Casing isolation 33
Thank you for showing interest Air Pollution Control Systems Where Experience and Innovation Meet 34 to front page