The complete skid‑mounted sludge dewatering package has finished assembly, joint commissioning and factory acceptance test and will soon be shipped to a customer in Europe. This solution consists of **GNDL303 Sludge Dewatering Screw Press** and **GNSJY3000 Chemical Dosing Unit**, with the whole workflow orchestrated by GN’s in‑house developed **GN Smart Control electric control system**, which acts as the intelligent brain for the entire skid‑mounted package GN Solids ....

Wastewater treatment operators across Europe are facing challenges of limited on‑site manpower, high sludge disposal cost and strict local electrical regulations. Conventional separate dewatering and polymer dosing equipment often suffer from poor process coordination, requiring frequent manual tuning and heavily relying on operator experience. To tackle such pain points, GN adopts GN Smart Control integrated control solution to realize deep‑level process interlock between screw press and chemical dosing unit, forming a closed‑loop sludge treatment workflow.

GN Smart Control — Intelligent Central Brain of the Package

Developed in‑house for solid‑liquid separation equipment, GN Smart Control adopts PLC and HMI touch‑screen architecture. The control cabinet is engineered in compliance with European electrical standards with full EMC protection and safety interlock functions to meet overseas project requirements. Beyond simple start‑stop control, it coordinates the full workflow including sludge feeding, polymer preparation, chemical dosing, screw extrusion dewatering, cake discharge and filtrate return.

 **Multi‑unit process interlock**: GN Smart Control synchronizes GNDL303 screw press and GNSJY3000 dosing unit. According to real‑time sludge feed load, the system automatically adjusts dry‑polymer feeding, mixing, curing and metered output. When abnormal load occurs on the screw press, the control system will adjust chemical dosing or trigger alarm and shutdown, preventing poor flocculation and polymer waste.
 **Full‑automatic operation to cut on‑site attendance**: Both automatic and manual modes are available. One‑touch startup enables unattended continuous operation. All process data such as motor current, feed flow, liquid level and running hours are displayed on HMI for straightforward operation.
**Built‑in fault diagnosis & safety protection**: Overload, low/high‑level, feed loss, motor overheating and interlock shutdown logics are integrated. HMI shows fault code and description for fast troubleshooting to minimize downtime.
 **Open communication interface for plant digitalization**: Reserved industrial communication ports support connection to customer‑site SCADA system for remote monitoring, matching digital operation requirements of European plants.

Process Units Maximized by GN Smart Control

GNDL303 Sludge Dewatering Screw Press

As the solid‑liquid separation executor, it transmits real‑time screw rotating speed and torque data to GN Smart Control. Facing fluctuating sludge concentration, the control system gives early warning and coordinates dosing unit for process adaptation. Overload and jam protection are implemented by GN Smart Control for stable dewatering performance with consistent cake dryness.

GNSJY3000 Automatic Chemical Dosing Unit

All procedures of the three‑chamber dosing unit are managed by GN Smart Control: dry powder feeding, water proportioning, mixing‑curing and metered dosing. Liquid‑level interlock stabilizes polymer solution concentration. Signal exchange between dosing unit and screw press achieves well‑matched sludge‑polymer conditioning performance.

All mechanical parts, piping and wiring are pre‑integrated and pre‑tested on one skid base in GN factory, with control logic pre‑commissioned within GN Smart Control. Upon arrival at European site, customers only need to connect power, sludge inlet, water and discharge pipelines for quick commissioning, greatly reducing field wiring and debugging workload.

This shipment demonstrates GN’s capability of delivering turn‑key solutions combining process machinery and self‑developed GN Smart Control electric products, rather than supplying standalone machines only. Going forward, GN Smart Control will keep upgrading to deliver safer, smarter and local‑standard‑compliant automation control for municipal and industrial sludge‑treatment projects worldwide.