Picket Fence Thickener
The ZCN-type suspended center-drive picket fence thickener is a form of sludge thickening equipment specifically for small and medium gravity sludge thickening tanks at municipal wastewater treatment plants and industrial wastewater treatment projects. The sludge thickener thickens sludge utilizing gravity settling, reducing the sludge volume that needs further treatment, and typically serves as sludge pre-thickening ahead of mechanical dewatering.
The ZCN-type picket fence thickener utilizes a suspended center-drive structure. After sludge enters the tank, a feedwell distributes it evenly. The drive unit slowly turns the center shaft, scraper arms, and picket fence bars. The sludge settles under gravity and gathers at the tank floor, while the picket fence bars gently stir the sludge layer to promote water release. The supernatant flows over the peripheral outlet weir into the effluent channel. This form of sludge handling equipment can operate upstream of mechanical dewatering systems.
| Model | |||||||||
| Tank Diameter Ø (m) | 5 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 |
| Peripheral Tank Depth H (m) | 3.5–4.5 (as required) | 3.5–4.5 (as required) | 3.5–4.5 (as required) | ||||||
| Water Depth at Tank Wall H₁ (m) | 3.0–4.0 (as required) | 3.0–4.0 (as required) | 3.0–4.0 (as required) | ||||||
| Peripheral Speed v (m/min) | 1.5–3.0 | 1.5–3.0 | 1.5–3.0 | ||||||
| Motor Power N (kW) | 0.37 | 0.55 | 0.75 | ||||||
| Installation Dimensions (mm) | 1,050 | 1,050 | 1,050 | 1,050 | 1,250 | 1,250 | 1,250 | 1,250 | 1,250 |
| 1,000 | 1,000 | 1,000 | 1,000 | 1,200 | 1,200 | 1,200 | 1,200 | 1,200 | |
| 500 | 500 | 500 | 500 | 800 | 800 | 800 | 800 | 800 | |
| 700 | 700 | 700 | 700 | 800 | 800 | 800 | 800 | 800 | |
| Working Bridge End Load P₂ (kN) | 30 | 33 | 36 | 40 | 48 | 55 | 65 | 72 | 81 |
| Maximum Operating Torque M (N·m) | 19 | 22.5 | 45 | 56 | 67 | 100 | 122 | 148 | 172 |
- Picket fence bars on the scraper arms assist thickening and water release
- Working bridge in carbon steel, stainless steel, or concrete, based on project requirements
- Submerged support structure and sludge scraping device at the lower end of the center shaft, which helps keep operation stable and clears the sludge collection area
- Mechanical and electrical overload protection, supporting local and remote control