Sulzer tertiary treatment delivers class A irrigation water

A wastewater treatment plant (WWTP) in Spain has completed a project to expand its capacity and improve effluent water quality at the same time. The installation of additional filtration equipment from Sulzer has enabled the plant to meet Class A water standards, allowing it to be used for irrigation and support local agriculture with a sustainable source of water. The project has enabled the WWTP to be the first in Spain where a tertiary treatment has achieved Class A water quality for irrigation.

“This is the first tertiary treatment installation in Spain to achieve class A water quality, making it suitable for immediate use agriculture – a major step forward for improved water sustainability.”

Maria del Mar Aymerich, Sulzer

The challenge
The plant had already installed DynaSand filters in 2007. Following their success, the operator wanted to increase capacity and improve the quality of water to a level acceptable for agricultural irrigation. European regulations specify minimum quality standards for water reuse, and these needed to be exceeded by the revised installation. More specifically giving warranty of very low turbidity, phosphorus removal, absence of nematode eggs and strict bacteriological reductions.

The plan to double the treatment capacity of the plant at the same time would require expert specification and planning to ensure an efficient installation.

The solution
Sulzer supplied 15 DynaSand filters with continuous backwashing as well as the pumps and auxiliary systems. In addition, a DynaDisc unit providing 10-micron filtration, including an automated cleaning system, was also installed.

The final step required ultra-violet disinfection. Sulzer and its specialist partner on disinfection, provided the WWTP with a complete tertiary treatment solution and full warranty on the water quality at the outlet from the tertiary treatment plant.

Customer benefit
Following the successful upgrade, the WWTP’s capacity is now 30’000 m³/day, which is supplied primarily for agriculture, but also urban and recreational use. The additional filtration equipment has expanded throughput and also achieved authorization from local government for water reuse.

This additional resource will help to address local water scarcity and reduce water stress in the area.