What is the handling of solids? | WWD
Solids handling includes thickening, digestion, dewatering, and sludge disposal / reuse.
What is solids management?
The processes used to stabilize sludge and reduce its volume are known as solids treatment.
The process occurs when a wastewater treatment plant is functioning properly. Most of the solids in the wastewater will be removed at the plant, while the water is discharged as an effluent to the receiving water. These solids, or sludges, must be stabilized and reduced in volume before they can be reused or disposed of.
Solids handling includes thickening, digestion, dewatering and sludge disposal / reuse.
Once the sludge is treated, it can be converted to biosolids. Biosolids can be used for compost, fertilizer and landfill cover.
Biosolids can add nutrients, improve soil structure, and improve moisture retention.
Handling solids can reduce downtime and labor costs. Some foreign debris that can be avoided through the solids handling process include: disposable wipes, string, rags, hair, plastic shards and more.
What solids handling equipment can be used?
Two-shaft macerators and crushers are two options for stabilizing sludge.
Macerators are designed for in-line piping installations and protect against solids and damage to downstream pumps and equipment. Macerators must circulate liquid through the hose as they cannot run dry. This method works best with smaller solids like hair, rags, and plastics.
Maceration produces ideal results when installed after primary or overhead screening systems. Macerators cannot cut through hard solids like rocks, metals, etc.
When an object becomes lodged in the screen and cannot be cut during the first pass through the grinder, an increase in intensity is detected by the control panel and causes the Smart Relay to launch the Auto Reverse program. Ultimately, this can help remove the lodged object.
Double shaft shredders
Double shaft crushers are designed for pipe installations and in-line channels. Unlike macerators, crushers can run dry continuously and can process larger solids to protect against solids and damage to downstream pumps and equipment.
Double shaft grinders operate with two counteroperating shafts with cutting blades attached. As the cutting blades rotate, solids are drawn to the center between the cutting blades. All solid materials are processed by the crusher, with no debris trap.
Liquid, however, still flows around the outer opening of the housing, against rotation. The diagram on the right illustrates the principle. All the fluids that pass through the pipeline pass through the blades of the crusher, so everything is crushed into small particles.