Waste water treatment at your construction site

Proper water management at construction and tunnel sites provides many advantages. Even the rain and ground water that finds its way into a project site can be managed to increase the efficiency of the process. Alfa Laval decanter centrifuge is the technology you can trust to help you manage the water through one of the most effective separation technologies there is. This process saves time, money, resources and can help you meet the increasing regulatory demands facing the industry.

• Small footprint equipment that delivers big results 
• Fine particle separation, unlike sedimentation tanks
• Produces a drier solid that is less expensive and easier to dispose of
• Meets requirements for water disposal or re-use, such as suspended solids, acidity (pH), and biological and chemical oxygen demans
• Low operating costs and high separation capacity help contractors to compete effectively 

The importance of cleaning waste water at your construction site

The construction and engineering industries play a crucial role in the continued social and economic development of our world. Any serious project (whether public or private) is now subject to requirements to minimize impacts on people and the environment. A contractor’s environmental impact assessments (EIA) and environmental management plans (EMP) set the minimum levels for efficient use of resources, the protection of biodiversity, climate change and, not least the risk of accidents and the protection of our health in general.

An important part of a construction project’s EIA is water management, especially in civil engineering. Water plays a key role whether it is used in excavation and foundations, to cool machines, keep pressure, move solids (for example tunnel boring machines, drilling rigs and cutting machines) or as a means of cleaning. Rainwater and effluent seepage also need to be managed. Companies that can optimize consumption and ensure water meets the national and local regulations regarding cleanliness will always be at an advantage.

Alfa Laval’s range of centrifuge decanters are built to meet the high environmental demands for solid-liquid separation in tunnelling construction and similar applications. The proven separation technology removes the finest particles (unlike sedimentation tanks) making it easier to meet requirements for water disposal or re-use, such as suspended solids, acidity (pH), and biological and chemical oxygen demand. Low operating costs and high separation capacity help contractors to compete effectively and to meet these evermore-stringent environmental demands.

On-site production waste water

While the volume of water needing to be treated for the operation of your construction drilling process may vary from site to site, the requirement to clean it remains none the less. Implementing an Alfa Laval LYNX decanter will significantly lower the costs of transporting untreated water away from the site while decreasing treatment costs as well. This process makes it possible to reuse the water, thus reducing the need to buy and ship water in as well. However, reusing water that is not properly cleaned can lead to damage in other equipment. Alfa Laval takes care of those demands with equipment that has a footprint small enough to fit in your site while producing big enough results to help you meet the regulations you face.

On-site rain and ground water

Alfa Laval LYNX decanters deliver effective and cost-efficient rain and groundwater treatment. Water that may become contaminated with items used on the site. Regardless of how water finds its way on to your site, the responsibility of treating it should not be a major issue for you. Let Alfa Laval, with our extensive experience in the construction drilling industry, help you meet these regulatory requirements in as simple a way as possible.

How it works - decanter

The rotating assembly is supported on a compact welded box beam frame with main bearings at both ends. The in-line main motor is flange- or foot mounted onto the unit with adjustable brackets for belt tension adjustment. The bowl is driven at the conical end by an electric motor with a V-belt transmission. The bowl, conveyor, casing, inlet tube, outlets and other parts in contact with the process media are made of AISI 316 or duplex stainless steel with tungsten carbide inserts in the areas most susceptible to wear.

Separation takes place in a horizontal cylindrical bowl equipped with a screw conveyor. The feed enters the bowl through a stationary inlet tube and is accelerated smoothly by an inlet rotor. Centrifugal forces cause sedimentation of the solids on the wall of the bowl. The conveyor rotates in the same direction as the bowl, but at a different speed, thus moving the solids towards the conical end of the bowl. The design enables the decanter to scroll out high loads of solids without blockages caused by high levels of dryness. Only the very driest fraction of the sludge cake leaves the bowl through the solids discharge openings into the casing.

The decanter centrifuge can be adjusted to suit specific requirements by varying the bowl speed, the conveying speed, the pond depth and the feed rate

Product portfolio

LYNX construction drilling decanter

Alfa Laval LYNX centrifugal decanter systems are made for muck handling. They efficiently remove solid particles from water and oil-based slurries resulting in better penetration rates, shorter drill times, less wear on key components as well as longer sludge service life. It also reduces chemical usage as well as drill waste, which contributes to lower disposal and waste water treatment costs.

Normally installed in a bypass system, our LYNX centrifugal decanters operate continuously without interrupting drilling operations. The range can handle muck flow rates from 5 m3/hour up to 100 m3/hour. The variable bowl speed ensures the right G force required for the most efficient separation while the conveying speed can be adjusted for optimal balance between liquid clarity and solids dryness. The adjustable pond depth also contributes to the best balance between clarity and dryness.

• Developed specifically for the tunnel boring and construction industry
• Small footprint – easy installation and mobilization
• Continuous and automatic operation with option of remote surveillance
• High separation efficiency – clean slurry improves drill penetration rate
• Highly sustainable cleaning capacity – less waste due to dry cake and reused slurry