Optimal Sludge treatment of your wastewater
Alumichem provide sludge treatment chemicals, equipment, and the expertise to optimize the sludge thickening and dewatering process.
Optimal combination of equipment, dewatering chemicals and process tuning, results in cost effective sludge treatment.
Sludge treatment is an important part of the wastewater treatment process, including both biological and chemical wastewater treatment plants. The first step is often a thickening process, where the solid content of the sludge needs to be increased, either for further processing of the sludge in a digester, or simply to condition the sludge, before feeding it to the dewatering equipment. Dewatering of sludge has most often a goal of achieving the highest possible dry matter content, reducing the volume significantly.
In many biological wastewater treatment plants, the sludge undergoes a thickening process after biological treatment, before entering the digester for biogas production. In the thickening process, the goal is to remove water and increase the dry matter content in the sludge, to a level that is optimal for the digester. Often this means increasing the dry matter to 5-7%, where sludge is still pumpable, but still containing a lot of solid material for digestion.
The thickening is done by adding dewatering chemicals, most often polymer, to the sludge which flocculates the solids and separates water. Dewatering equipment is used to separate the released water phase from the sludge. Equipment used could be rotating drum filter, centrifuge or other.
In chemical treatment plants, sludge thickening may be included if the sludge from a flocculation process is too wet (dry matter content too low), to feed directly to dewatering equipment.
Dewatering of sludge is the final step before disposing the sludge (unless a sludge drying step is added), so the goal is to remove as much water as possible, leaving a high dry matter content. In this process a polymer is added to create strong flocs that can withstand the shear forces needed to press as much water as possible from the solids in the sludge.
Depending on the nature of the sludge and the dewatering equipment, different types of polymers may be used. Choosing the right polymer and optimizing equipment settings will have a huge impact on the result of the process and thereby the cost of disposal.
In biological and larger chemical wastewater treatment plants dewatering equipment like decanter centrifuge or screw press is often used, but other equipment may also be used. In small scale industrial chemical treatment plants, the process may be a separation in a drum or belt filter, combined with big bag dewatering, where the sludge is left in a big bag for final water release. This can be a cheap way to dewater sludge, but only suitable for low sludge volumes and when sludge is biologically stable.
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Experts in Sludge Treatment
Our experts are experienced in process optimization, which include identifying the most suitable chemicals and optimizing the dewatering process from dosing of chemicals to optimizing settings of the equipment used.