Mechanical dewatering separates sludge (residual sludge from wastewater treatment plants or faecal sludge from on-site sanitation systems) into a solid and a liquid part. It is a highly technical process that reduces the volume of the sludge, making it easier and less expensive to transport, compost, or incinerate.
What is Dewatering?
The process of mechanical dewatering involves pumping out water that has been collected on a construction site or excavation. This allows crews to work in drier conditions and reduces the risk of structural failure due to groundwater pressure or sand soiling.
In wastewater treatment plants, dewatering removes the water from sludge to make it easier to transport and dispose of. It also helps to reduce energy consumption by reducing the amount of energy needed to heat the sludge.
In construction, dewatering is essential for preparing a work area. It prevents mudslides and equipment failure caused by standing water and provides a stable foundation for building. In addition, it ensures worker safety and prevents environmental damage by reducing harmful pollutants discharged into natural water courses and rivers.
Why is Dewatering Important?
Dewatering is a critical step in construction, especially during the excavation and foundation stages. Uncontrolled groundwater can flood excavated areas, damage construction materials, cause trench collapses, and threaten the safety of crew members.
In addition to removing excess water, dewatering also allows for more accurate soil assessments and reduces the negative environmental impact of your construction project. Selecting the right dewatering method based on your soil conditions and water table level is important.
Dewatering Processes
Construction sites often use dewatering methods to remove water accumulated in excavations and trenches. This is important to protect materials and equipment from damage caused by water and also helps keep workers safe.
Mechanical dewatering separates sludge (residual sludge from wastewater treatment plants or faecal sludge from on-site sanitation) into liquid and solid parts. Still, it does not treat the sludge to remove pathogens or pollutants. Instead, the dewatered sludge is transported and stored.
This dewatering method uses a belt filter press or centrifuge to extract the water from the sludge. It also relies on air drying to achieve the final dry solid product, but it requires large land areas and can be heavily influenced by weather conditions. In addition, local and federal agencies typically regulate discharged groundwater to ensure that harmful pollutants are not released into the environment.
Dewatering Equipment
Manufacturer of equipment for industrial dewatering systems. Provides vacuum pumps, suction/the boxes, strips & covers for vacuum box & gravity filters, and barometric drop legs. It also provides lubrication showers, separators of vacuum process water, discharge pumps, and liquid ring vacuum pumps. Offers 24-hour customer services, including pump selection, installation & maintenance.
Dewatering filters separate solids from liquid components, creating dry, more easily handled material and reusable process water. They can be used to dewater municipal, tank, paint & industrial sludges; drilling mud; and frac sands. They also help reduce stockpile drying time and free up space on your site. Centrifuges are the most popular type of dewatering equipment. They sling the water out using centrifugal force.
Dewatering Solutions
Construction sites often have accumulated surface and subsurface water that needs to be removed before excavation works can begin. This is important for keeping the site safe by preventing dirt from becoming slippery mud, providing stabilization and erosion control, and ensuring all the work can be completed on time.
Four major dewatering solutions can be employed: sump pumping, well point systems, eductor wells, and deep wells. These methods can be used alone or in combination depending on the soil and hydrologic conditions.
While the most common way to remove water from a construction site is to pump it away, paying attention to where you discharge the water is important. If the water is pumped to lakes, rivers, wetlands, or directly to storm sewer inlets, it could cause problems such as erosion and sedimentation.
