--- title: "Bar Screens and Rotary Drum Filters" description: "Mechanical bar screens and rotary drum filters (micro screens) that remove debris and fine solids from wastewater, process water and aquaculture water." url: https://www.waste-water-equipment-factory.com/products/screening-filtration/ updated: 2026-11-10 --- # Screening & Filtration First-line protection that removes debris and fine solids from water. Screening and filtration equipment removes floating debris, rags, fibers and suspended solids from water before they can damage pumps or overload downstream treatment. Mechanical bar screens are used at the inlet of municipal and industrial wastewater plants, while rotary drum filters (micro screens) are used for fine solids removal in wastewater, process water and recirculating aquaculture systems. ## How it works A mechanical bar screen is installed in a channel at an angle to the flow. Water passes between parallel bars or a mesh, and solids larger than the openings are retained. A rake or chain-driven mechanism lifts the captured material to a discharge point, where it drops into a bin or conveyor. A rotary drum filter consists of a slowly rotating drum covered with fine mesh. Water flows through the mesh, leaving solids on the screen surface. As the drum turns, a spray bar backwashes the retained solids into a collection trough, allowing continuous filtration without stopping flow. ## Models - [Rotary Rake Mechanical Bar Screen, SS304](https://www.waste-water-equipment-factory.com/products/screening-filtration/rotary-rake-mechanical-bar-screen/): This mechanical bar screen uses a 304 stainless steel rotary rake to remove floating debris and coarse solids from wastewater at the plant inlet. It runs automatically 24 hours a day, protecting pumps and downstream equipment from clogging. It is designed for municipal sewage plants and industrial wastewater systems that need reliable solid-liquid separation at the headworks. - [Rotary Drum Micro-Filter, SS304/316](https://www.waste-water-equipment-factory.com/products/screening-filtration/rotary-drum-micro-filter/): This rotary drum water filtering machine uses a welded SS304/316 wire mesh screen to remove suspended particles in pretreatment. Water enters the rotating drum, solids are retained on the mesh and backwashed away, and filtered water flows out continuously. With a 10–500 m³/hour capacity range, it serves municipal, industrial and aquaculture systems that need low-maintenance mechanical filtration. - [Internal-Feed Rotary Drum Screen](https://www.waste-water-equipment-factory.com/products/screening-filtration/internal-feed-rotary-drum-screen/): This micro screen rotary drum separator dewaters fibrous materials such as seaweed, sugarcane bagasse and paper pulp. A rotating stainless steel screen retains solids while water drains through, and PLC control allows 24-hour automatic operation. It is intended for seaweed, sugar and pulp processors that need continuous, low-labor separation of solids from process water. ## How to choose - **Opening size:** Coarse screens protect pumps and equipment, fine screens reduce solids loading on downstream processes, and micro screens capture very fine particles. Choose the opening to suit the process objective. - **Flow rate and channel dimensions:** Size the screen for peak flow at an acceptable approach velocity and head loss. Existing channel width and depth often fix the frame size. - **Type of solids:** Rags, fibers, hair, grease and sand behave differently on screens. Fibrous or sticky solids may require a specific screen design or cleaning method. - **Cleaning and backwash:** Check the cleaning mechanism, backwash water demand and pressure, and how screenings will be washed, compacted or removed. - **Materials and environment:** Stainless steel is common for wetted parts. Consider corrosion, outdoor exposure and whether the screen must be enclosed for odor control. ## Applications - Municipal wastewater plant headworks - Pump station protection - Food processing and slaughterhouse wastewater - Pulp and paper fiber recovery - Recirculating aquaculture systems - Textile and tannery effluent - Pretreatment before DAF or MBR ## FAQ ### What is the difference between a bar screen and a rotary drum filter? A bar screen uses parallel bars or a mesh in a channel to remove coarse and medium debris. A rotary drum filter uses fine mesh on a rotating drum with backwash to remove much finer suspended solids. ### Why is screening important before MBR treatment? Membranes are vulnerable to hair, fibers and debris that can clog or damage modules. Fine screening upstream is a standard requirement for reliable MBR operation. ### How are rotary drum filters cleaned? Spray nozzles backwash the mesh from the inside or outside as the drum rotates, washing retained solids into a trough. Cleaning is automatic and can be triggered by water level or timer. ### Are rotary drum filters used in aquaculture? Yes. They are widely used in recirculating aquaculture systems to remove fish feces and uneaten feed before biological filtration. ## Contact - Email: inquiry@waste-water-equipment-factory.com - WhatsApp / Tel: +86 176 2154 1688 - Quotation form: https://www.waste-water-equipment-factory.com/contact/ - Company: Shanghai Mars Industrial Co., Ltd., Shanghai, China