DAGYEE High pressure belt sludge dewatering machine

Introduction to DAGYEE Solutions:Auto Sludge Dewatering Screw Press Sludge Solid Liquid Separator

About This Guide:

This document is designed to serve engineers, plant managers, environmental consultants, and procurement officers who are evaluating sludge dewatering technologies. As a specialized manufacturer, **DAGYEE** focuses on tailoring Multi-disk Screw Press solutions to meet specific sludge characteristics and discharge requirements. Unlike off-the-shelf trading companies, we engineer our units to fit your process.

## Section 1: Fundamentals & Working Principles

### **Q1: What is a Multi-Disk Screw Press, and how is it different from a traditional screw press?**

**Multi-Disk Screw Press** (often called a Volute Dewatering Press) is distinct from a traditional high-pressure screw press used in food processing.

* **Traditional Screw Press:** Uses a screw inside a perforated metal screen. It requires high pressure and often clogs easily with sticky sludge.

* **DAGYEE Multi-Disk Screw Press:** Uses a unique filtration body consisting of a central screw shaft running through a series of rings. These rings are stacked: **Fixed Rings** and **Moving Rings** alternate.

* As the screw rotates, it pushes the edges of the Moving Rings against the Fixed Rings.

* This constant movement creates a self-cleaning action that prevents clogging.

* This design allows it to handle oily and sticky sludges that would destroy a belt press or clog a filter press.

### **Q2: How does the dewatering process work step-by-step?**

The process inside a DAGYEE unit occurs in three distinct zones:

1.  **Conditioning (Flocculation):** Sludge is pumped into the Flocculation Tank where it is mixed with polymer. This creates "flocs" (clusters of solids) and separates free water.

2.  **Thickening Zone:** The flocculated sludge enters the thickening zone of the screw body. Here, the spacing between the screw pitch is wider, and the gaps between the rings are larger. Gravity drains the majority of the filtrate (free water).

3.  **Dewatering Zone:** As sludge moves toward the discharge end, the screw pitch narrows, and the gaps between the rings become tighter. This progressively increases internal pressure.

4.  **Discharge:** An adjustable **End Plate (Back Pressure Plate)** at the outlet restricts the flow, creating maximum pressure to squeeze out the remaining water before the dry sludge cake is discharged.

### **Q3: Why is the "Self-Cleaning" mechanism so important?**

In traditional dewatering (like Filter Presses or Belt Presses), the filter cloth meshes get blocked by fine particles or grease. This requires massive amounts of high-pressure wash water to clean.

In the **DAGYEE Screw Press**, the moving rings are constantly shifting relative to the fixed rings. This continuous motion naturally dislodges any particles stuck in the gaps.

* **Benefit:** It prevents clogging.

* **Benefit:** It enables the machine to run continuously (24/7) without operator intervention.

* **Benefit:** It drastically reduces wash water consumption (cleaning is only needed periodically for the exterior of the rings, not to unblock the filter).

### **Q4: What is the typical Dry Solids (DS) content I can expect?**

The output dryness depends heavily on the *nature* of your sludge, not just the machine.

* **Biological Sludge (WAS/RAS):** Typically **15% – 20%** Dry Solids.

* **Coagulated Chemical Sludge:** Typically **20% – 25%** Dry Solids.

* **Paper/Pulp Fiber Sludge:** Can achieve **25% – 35%** Dry Solids.

* **Oily Sludge (DAF Float):** Typically **12% – 18%** Dry Solids.

*Note:* While a Filter Press might achieve slightly higher dryness (e.g., 30%), the Screw Press offers significant savings in labor, energy, and water, making the overall OPEX (Operational Expenditure) lower despite a slightly wetter cake.

## Section 2: Comparison with Other Technologies

### **Q5: How does DAGYEE Screw Press compare to a Belt filter press?**

* **Odor:** Belt presses are open systems; odors spread easily. DAGYEE Screw Presses are enclosed, minimizing odor.

* **Water Usage:** Belt presses require continuous high-pressure spray bars to keep the belt clean. A Screw Press uses <1% of the water required by a belt press.

* **Footprint:** Screw presses are more compact.

* **Wear & Tear:** Belt presses have belts, rollers, and bearings that wear out frequently. The Screw Press has one major moving part (the shaft) which turns very slowly (<4 RPM), resulting in minimal wear.

### **Q6: How does it compare to a Decanter Centrifuge?**

* **Energy:** Centrifuges spin at 3000+ RPM and consume massive amounts of electricity. DAGYEE Screw Presses spin at 2–4 RPM. The energy consumption is roughly **1/10th** of a centrifuge.

* **Noise:** Centrifuges are very noisy (>80dB). Screw Presses are almost silent (<60dB).

* **Vibration:** Centrifuges require special heavy foundations. Screw Presses can be mounted on skids or standard floors.

### **Q7: How does it compare to a Plate & Frame Filter Press?**

* **Automation:** Filter presses usually run in batches (Batch process). They require an operator to open the press and shake out the cakes. DAGYEE Screw Presses run **continuously** and are fully automated.

* **Labor:** Filter presses have high labor costs. Screw Presses are "Set and Forget."

* **Consistency:** Filter presses handle inorganic sludge well but struggle with sticky biological sludge. Screw Presses excel with sticky sludge.

## Section 3: DAGYEE Customization & Engineering

### **Q8: What construction materials can DAGYEE provide?**

Standard units are usually SS304. However, because we manufacture to order, we can customize based on corrosion levels:

* **SS304:** Standard for municipal sewage and general industry.

* **SS316/316L:** Required for high-salinity (seawater), food and beverage, or pharmaceutical applications.

* **Duplex Stainless Steel (2205):** For extremely abrasive or high-chloride environments.

* **Shaft Surfacing:** We can apply Tungsten Carbide or hardened surfacing to the screw edges for abrasive sludges (like sand washing or mining).

### **Q9: Can DAGYEE customize the system for "Oily Sludge"?**

Yes, this is a specialty of the Screw Press.

* We do not use filter cloths, so oil cannot "blind" the filter.

* For high oil content (e.g., slaughterhouses, refineries, DAF sludge), we can adjust the **ring spacing gaps** to be slightly wider to facilitate flow and prevent pressure blockage.

* We can also upgrade the **motor power** to handle the higher viscosity of oily sludge.

### **Q10: Can you supply a "Containerized" or "Skid-Mounted" solution?**

Absolutely. DAGYEE specializes in plug-and-play systems.

* **Skid-Mounted:** We mount the Screw Press, the Polymer Dosing Unit, the Sludge Feed Pump, and the Control Panel on a single SS or CS skid. You only need to connect power and pipes.

* **Containerized:** For mobile applications or sites without buildings, we install the entire system inside a 20ft or 40ft ISO container, complete with lighting, ventilation, and non-slip flooring.

### **Q11: How do you size the machine? What is the model number meaning?**

Our models (e.g., MDL-301, MDL-302) usually refer to the diameter of the screw and the number of shafts.

* **Screw Diameter:** 100mm, 130mm, 200mm, 300mm, 400mm, etc.

* **Number of Shafts:** We can build single-shaft, double-shaft, or even triple-shaft machines to handle massive flows.

* **Sizing Factor:** We size based on **Dry Solids Loading Rate (kg-DS/hr)**, not just hydraulic flow ($m^3/hr$). A flow of 10 $m^3/hr$ at 1% concentration is very different from 10 $m^3/hr$ at 3% concentration.

### **Q12: Do you offer Explosion-Proof (ATEX/Ex-Proof) options?**

Yes. For Oil & Gas or Petrochemical clients, we can equip the unit with:

* Explosion-proof Motors (Ex d II BT4, etc.).

* Explosion-proof Control Panels.

* Anti-static wiring and grounding.

As environmental policies tighten and the development of ‘Zero-Waste Cities’ advances, efficient sludge dewatering technology has become a key driver for sustainable development. Moving forward, DAGYEE remains committed to innovation, dedicated to providing smarter and more energy-efficient sludge treatment solutions for municipal and industrial clients. We will continue to empower global customers to tackle environmental challenges with cutting-edge technology, working together to chart a new course for a greener future.