Coal-fired power plants clean their flue gas with a wet lime slurry process, absorbing more than 95% of the sulphur dioxide (SO2) before it reaches the stack. This reaction produces large volumes of gypsum slurry that must be dewatered into a dry, reusable by-product — and this is where the vacuum filter belt does its critical work. On a horizontal vacuum belt filter, the belt carries the gypsum slurry over a vacuum chamber, drawing the water through the mesh to leave a dry filter cake.
The wet lime slurry method is the most widely used flue gas desulfurization (FGD) process: it absorbs SO2 quickly, adapts well to a wide range of fuels, and is installed in about 90% of coal-fired power plants worldwide, especially large-capacity units. The high-purity by-product gypsum (>90% purity) is recycled and reused as building material — turning a pollutant into a saleable product.
On a horizontal vacuum belt filter, the filter belt forms a continuous moving filter surface. Gypsum slurry from the absorber is fed onto the belt, vacuum is applied from below, and the liquid is pulled through the mesh while the gypsum solids build up as a filter cake that is washed, dried and discharged — continuously, without stopping the process.
Step 1 Slurry Feed Gypsum slurry from the absorber is fed evenly onto the moving filter belt. | Step 2 Vacuum Filtration Vacuum pulls the liquid through the belt, forming a gypsum filter cake on top. | Step 3 Washing & Drying The cake is washed and further dewatered to raise gypsum purity and dryness. | Step 4 Gypsum Discharge The dry gypsum cake releases cleanly for recycling as building material. |
01 High Permeability Good air and water permeability for fast, efficient gypsum dewatering | 02 Uniform Aperture Uniform, precise aperture for consistent filtration and clean filter cake | 03 Easy to Clean Easy fabric cleaning with good filter cake release between cycles | 04 Dimensional Stability Good dimensional stability with stainless steel 316 clipper seam and apron cover |
| Coal-Fired Power Plants● Dewatering FGD gypsum in horizontal vacuum belt filters● Wet lime slurry desulfurization process● Large-capacity generating units | Gypsum Recycling● Producing >90% purity by-product gypsum● Recycling gypsum as building material● Turning a pollutant into a saleable product |
To deliver this dewatering performance, PFM Screen weaves its vacuum filter belt with polyester monofilament on the diameter (warp) yarn and multifilament on the weft yarn — combining high filtration efficiency and good air permeability with strong mechanical strength. Robust PFM Screen filter mesh belts are deployed for the fast and efficient dewatering of FGD gypsum in vacuum belt filters.
● Easy cleaning of the fabric ● Good filter cake release ● Uniform precise aperture | ● Good filtration property and air & water permeability ● Stainless steel 316 clipper seam with apron cover cloth ● Good dimension stability |
| Feature | Detail |
|---|---|
| Warp yarn | Polyester monofilament — strength and wear resistance |
| Weft yarn | Polyester multifilament — filtration fineness and air permeability |
| Aperture | Uniform, precise aperture for consistent filter cake |
| Seam | Stainless steel 316 clipper seam with apron cover cloth |
| Stability | Good dimensional stability for straight running under vacuum |
View Vacuum Filter Belt Product
Q1: What is an FGD vacuum filter belt? It is a filter mesh belt used in horizontal vacuum belt filters to dewater the gypsum produced during the wet flue gas desulfurisation process in coal-fired power plants. |
Q2: What construction gives the belt its strength and permeability? The belt is woven with polyester monofilament on the diameter (warp) yarn and multifilament on the weft yarn, combining high filtration efficiency and air permeability with strong mechanical strength. |
Q3: What joining/seam options are available? The belt uses a stainless steel 316 clipper seam with an apron cover cloth for secure, reliable joining and good dimensional stability. |
Q4: Can the belt match my existing vacuum belt filter? Yes. We manufacture to your exact width, length and seam type, and can match an existing belt for a drop-in replacement on your horizontal vacuum filter. |
Q5: What is the purity of the gypsum produced? The wet lime slurry process produces high-purity by-product gypsum with purity above 90%, which is recycled and reused as building material. |
Q6: How do I get a quote? Send your belt width/length, vacuum filter model and mesh preference to polyestermesh@pfmscreen.com or WhatsApp +86 153 6967 9157 for a factory-direct quotation. |
Get a Custom FGD Vacuum Filter Belt Specification Within 24 Hours Share your belt width/length, vacuum filter model and mesh preference — PFM Screen will recommend the right belt and send a factory-direct quotation. WhatsApp: +86 153 6967 9157 Email: polyestermesh@pfmscreen.com |
