1、 Product Features
Walnut shell filter is a filtering device suitable for oily wastewater treatment. The device uses walnut shells with strong adsorption capacity, compressive strength, stable chemical properties, high hardness, good hydrophilicity, oil resistance, and special processing as the filter material. Its characteristic is that the filter material is easy to backwash and regenerate, and can be directly backwashed with pre filtered water without the need for gas source and chemical agents.

2、 Scope of application
1. Suitable for the filtration treatment of oily wastewater and other oily wastewater recycling systems in the steel, metallurgical, and coal industries;
2. Suitable for fine filtration of oilfield reinjection water with large water volume, treatment of produced water from offshore oil platforms, and water treatment for thermal recovery boilers in heavy oil fields;
3. Suitable for filtration and deep treatment of cooling circulating water in power plants, refineries, and petrochemical plants.

3、 Product Features
Walnut shell filter is resistant to oil immersion, with dual effects of oil and suspended solids removal, strong adsorption capacity, and large interception capacity; Easy to regenerate, backwash and optional dosing.

4、 Technical parameters
1. Processing effect

straining	Inlet water: oil content, ≤ 100mg/L SS，≤50mg/L； Outlet water: oil content, ≤ 10mg/L SS，≤10mg/L；
refined filtration	Inlet water: oil content, ≤ 20mg/L SS，≤20mg/L； Outlet water: oil content, ≤ 5mg/L SS，≤5mg/L；
Secondary series connection	Inlet water: oil content, ≤ 100mg/L SS，≤50mg/L； Outlet water: oil content, ≤ 5mg/L SS，≤5mg/L；
filtration capability	6-20kg/m2

2. Working environment parameters
①. Working temperature: 5-60 ℃ (special temperature can be customized);
②. Work pressure: ≤ 0.6MPa；
③. Inlet water pressure: ≥ 0.04MPa；
④. Backwash inlet water pressure: ≥ 0.15 MPa；
⑤. Import and export pressure difference: 0.1-0.2 MPa.
3. Operating parameters
①. Working mode: pressure based;
②. Operation mode: Water flow from top to bottom;
③. Filtration speed: 20-25m/h;
④. Operating cycle: 8-24h;
⑤. Backwash method: Air water combined backwash;
⑥. Backwash water consumption: 1-3%;
⑦. Backwash strength: 4-15l/s • m2;
⑧. Backwash duration: 20-30 minutes;
⑨. Backwash expansion rate: 30-50%.

5、 Working principle
This filter is a separation device successfully developed based on the principle of filtration and separation. It uses oil resistant filter material - special walnut shell - as the filtering medium, and utilizes the characteristics of walnut shell, such as large specific surface area, strong adsorption force, and large pollutant interception capacity, to remove oil and suspended solids from water. This device has two control modes: automatic and manual. When filtering, the water flows from top to bottom, passing through the water distributor, filter layer, and collector to complete the filtration. During backwashing, the agitator flips the filter material, and the water flow is from bottom to top to thoroughly clean and regenerate the filter material.

6、 Specifications, models, and external dimensions
1. Outline dimension diagram

2. List of Specifications and Models
List of Specifications and Models for Walnut Shell Filters
3. Model Description