As early as the ancient Egyptian period, people used simple tools to remove silt from the bottom of rivers, and after thousands of years of development, dredging technology has been applied to shipping, environmental protection, mining and many other fields. Undoubtedly, dredging has become an important means for human beings to transform nature and develop the economy.
This article will give you more professional information, including working principles, applications, dredger types and more.
What is Dredging?
Dredging projects are generally aimed at clearing, widening, and deepening rivers, lakes, and waterways, or building new ports and canals.
Dredging is the process of digging out silt, sand, gravel and other sediments from the bottom of rivers and lakes through mechanical equipment and transporting them to hopper or discharge them to the designated location.
Dredger is the main equipment in dredging projects. The dredging process generally includes dredging, transporting, and discharging mud.
Eco-friendly dredging dredgers regularly clean the silt in lakes, which can improve water quality and water ecological environment and prevent secondary pollution.
How Does Dredging Work?
Dredgers are the main equipment for dredging projects. Generally speaking, there are two main types of dredgers: hydraulic dredgers and mechanical dredgers. The following content will explain to you the main processes of dredging projects, dredging, transportation and discharge.
Dredging process: The cutter suction dredger or trailing suction hopper dredger uses a mechanical arm to push the cutter head and the drag head deep into the river bottom. The cutter head cuts the silt, gravel and other sediments on the river bottom into mud that is easy to transport.
Transportation process: Dredge pumps play an important role in the transportation process. Dredge pumps are installed in dredgers and connected to the river bottom through pipelines. Under the high-pressure water flow of the dredge pumps, the mud and water are mixed. Then the dredge pumps transport the mixed mud from the pipeline to the hopper of the dredger.
Discharge process: After the mud in the hopper is processed, it is transported to the designated location by a dredger and then discharged.
There are many ways to discharge dredged material, and the most common one is spray mud. After the dredging pump extracts the mud from the riverbed, it sprays the mud to the shore through a mud spraying pipe or transports it through a pipeline and then sprays it to the mud discharge location.
Watch & Learn: What is Dredging? [Explainer Video]
Why Dredging Matters? Where is Dredge used for?
Dredging has created enormous wealth for people. Countless seabed mineral resources have been excavated one by one, making dredging technology a tool for creating wealth.
Through dredging technology, humans can not only create islands and build ports, but also remove lake silt, restore the ecological environment, and make nature a better place.
Dredging for Industrial
Remove Silt: Dredging river silt, sand and gravel, Removal of tailings waste, Remove fly ash
Mineral Mining: Dredging for metal and sand mining, Deep sea mining, Mining of building materials
Construction: Island and reef construction, Port construction, Land reclamation, Excavation of new waterways and canals
Maintain: Dredging river channels, Widening and deepening waterways, Channel and port maintenance
Dredging for Environment
Garbage Removal: Remove underwater obstacles
ECO-Dredging: Remove polluted sludge and improve water quality, Restore wetlands and protect animal biodiversity, Widen the riverbed and reduce flood disasters
Coastline Protection: Prevent erosion from waves and tides
What Negative Impacts Might Dredging Have?
1. During the dredging process, the dredging equipment stirs up the sediment at the bottom of the lake, causing the silt to spread and pollute the surrounding waters.
2. When dredgers are transporting silt, the transport pipelines may leak, causing secondary pollution to the water body.
3. The excavated sediment may contain pollutants and may have an impact on the environment if not properly disposed of.
What Is A Dredger?
Dredgers are the main working equipment of dredging projects. Dredgers can dredge waterways, reclaim land, build islands and reefs, and even exploit marine resources. According to different working principles, there are three types of dredgers: hydraulic dredgers, mechanical dredgers and special dredgers. The following is a detailed introduction to different types of dredgers.
The Different Types of Dredges
Hydraulic Dredges
Hydraulic dredgers mainly use dredging pumps to suck mud into the hopper or directly transport it to the mud discharge site.
Cutter Suction Dredger: A cutter suction dredger is equipped with a rotatable cutter head at the head of the pipe. During dredging operations, the cutter head rotates to cut sand and impurities on the riverbed, and the dredging pump pumps the silt to the discharge site through the sludge suction pipe.
Trailing Suction Hopper Dredger: There is a drag head at the pipe head of the trailing suction dredger. Through the movement of the drag head, the dredger sucks in the silt and then transports the silt to the hopper through the dredging pump.
Suction Dredger: Suction dredgers do not have cutters or drag heads. It only relies on the strong suction of the dredging pump to suck the silt into the pipe. It is suitable for relatively soft soil.
Airlift Dredger: Airlift dredger mainly transports sediment through the principle of air compression, but its efficiency is relatively low and it is suitable for deep-water dredging.
Mechanical Dredges
Mechanical dredgers mainly use equipment such as grab buckets or backhoes to dredge up the mud and sand by making hard contact with it.
Grab Dredger: A grab dredger uses a boom to push the grab bucket deep into the river bottom. After the grab bucket grabs the mud and sand, the boom lifts the grab bucket out of the water to discharge the mud.
Backhoe Dredger: A backhoe dredger is like an excavator that uses a backhoe to dig mud and sand.
Bucket Dredger: Bucket dredger uses a chain with a bucket, driven by a guide wheel, to continuously dredge underwater. Bucket dredger has strong adaptability.
Special Type Dredges
Amphibious Dredger: Amphibious dredger can work not only in water but also on land. When working in water, it can float on the water through buoyancy devices.
Autonomous Dredger: Autonomous dredger can autonomously dig on the water through GPS positioning and intelligent facilities, saving manpower.
Dredging Equipment
Dredge Pump: Dredge pump is the core device of dredging project. The dredger sucks the silt from the river bottom into the pipeline through the strong suction of the pump, and then the dredge pump pressurizes the silt and discharges it.
Pipeline Transport System: Includes floating pipes and submerged pipes, used to transport excavated sediment.
Cutter Head: The suction cups on the cutter suction dredger can cut sand and impurities on the seabed, so that the dredger can suck up the dredged material more easily.
Drag Head: The drag head used to suck up silt on a trailing suction dredger.
Bucked: Used on bucket dredgers to dig out sand, gravel and debris.
How to Choose the Right Dredge for Your Project
There are several factors to consider when choosing the right dredging facility. Here are a few areas to consider.
Excavation method: Different dredgers have different excavation methods. You need to consider which industry your dredging project is in, construction or waterway maintenance?
Soil type: Different soil types require different dredgers. For example, mechanical dredgers are recommended for harder soil with larger particles, while hydraulic dredgers are recommended for softer, fine sandy soil.
Dredging workload: When choosing a dredging method, you need to consider the dredging workload and working time, which involves the power of the dredging pump and even the size of the dredger.
Cost control: With accurate cost control, you can narrow down the choices and design a cost-effective solution.
Conclusion
Dredging plays a very important role in today’s society. It can not only improve the increasingly harsh ecological environment, but also help humans create wealth and develop the economy. In the future, increasingly intelligent dredging equipment will make important contributions to the global ecological environment and water resources management.
If you have dredging needs, please feel free to contact Kingda experts and we will provide you with professional answers.
