Vacuum Belt Filter

A vacuum belt filter is an industrial filtration system that separates solids from liquids in slurries using a moving reinforced rubber belt with drainage holes. The vacuum-assisted filtration process achieves higher throughput and improved cake dewatering. The slurry is conveyed to the top of the belt, where a vacuum box draws the liquid through the belt and filter cloth, leaving a dewatered filter cake on the top. The filter cake can then be washed, dried, and discharged, forming a continuous unit process with applications in various industries, including mining, chemicals, and wastewater treatment.

Working Principle

1. Feed: The slurry passes through the feed box onto a horizontal conveyor belt.

2. Filter: This belt, consisting of filter cloth and a grooved drainage belt, passes through a vacuum box system.

3. Vacuum Action: The vacuum draws the liquid through the filter cloth and the belt's drainage holes, while the solids remain on the belt, forming a filter cake. 4. Dewatering and Washing: As the conveyor moves, the filter cake is vacuum-dewatered. The conveyor then passes through several stages where water sprays are used to clean and dry the cake.

4. Discharge: At the end of the process, the dewatered cake is removed from the conveyor with a knife.

5. Belt Cleaning: The filter cloth travels beneath the rubber belt and passes through a cleaning system before the next cycle begins.

Key Features and Benefits

1. High Throughput: Continuous, vacuum-assisted operation enables high filtration rates.

2. Continuous Operation: Filtration, cake cleaning, washing, and drying are all performed in a single, integrated unit.

3. Versatility: Effectively filters a wide range of slurries and materials containing heavy solids.

4. Improved Cake Dewatering: Vacuum support enables even better cake dewatering.

5. On-site Visibility: The operator can observe the entire filtration process from feed to discharge.

Common Applications

1. Mineral Processing: Filtering minerals, ores, and tailings.

2. Chemical Industry: Processing chemicals, catalysts, and dyes.

3. Wastewater Treatment: Dewatering and filtering sludge and flue gas desulfurization byproducts.

4. Food and Beverage: Used in separation processes in the food industry.