The Companhia Águas de Joinville (CAJ) in Brazil inaugurated the Jarivatuba wastewater treatment plant in October 2020, the largest such facility in the state of Santa Catarina. PENETRON ADMIX was used to treat all new concrete structures for protection from the aggressive sewage environment.
A major industrial, financial, and commerce center, Joinville is the largest city (600,000 inhabitants) in the state of Santa Catarina, in southern Brazil. The city’s previous wastewater treatment plant was in service for three decades and its operational capacity had reached its limits. Prior to the completion of the Jarivatuba facility, Joinville had one of the poorest rates of access to wastewater treatment in the country, with only 30% of households integrated into the municipal sewage network.
Bacteria activated by oxygen
Now considered one of the most modern facilities in Latin America, the new US$12 million Jarivatuba plant uses sequencing batch reactors (SBR), which utilize an ‘activated sludge process’ to treat wastewater. The SBR process treats the output from anaerobic digesters or mechanical biological treatment facilities in batches. Oxygen is injected into the mixture of wastewater and activated sludge to reduce the organic matter. Final disinfection of the treated effluent is done by a UV reactor system before release into the local watershed or for use in agriculture.
Featuring four large concrete treatment tanks, the treatment capacity of the new Jarivatuba plant is 600 liters/second, three times the capacity of the previous plant. At full capacity, the new plant will treat 90% of the sewage generated in Joinville.
Economic Benefits of WWTPs
“A more efficient and comprehensive sewage treatment system not only helps clean up the environment, but also reduces the incidences of disease in the local population,” explains Cláudio Neves Ourives, CEO & Managing Partner of Penetron Brazil. “This illustrates how the Jarivatuba plant will impact other sectors of the local economy. For example, every dollar invested in sanitation saves $4 in healthcare costs.”
Due to the high concentration of sulphate and chloride contents in the Joinville effluent, Cosatel, the general contractor, realized the WWTP project needed special protection to ensure the long-term durability of the Jarivatuba plant’s concrete structures. After consultation with the Penetron Brazil team, PENETRON ADMIX was specified to treat all the concrete structures, a total of approximately 12,000 m3 of concrete.
Keeping Concrete Impermeable
The active ingredients in PENETRON ADMIX react with water to form insoluble crystals, which fill in cracks, pores, and voids in the concrete – becoming an integral part of the concrete matrix. The formation of the crystals throughout the concrete matrix results in impermeable concrete. These crystals prevent liquid molecules (and harmful chemicals found in effluent) to pass through the concrete that would otherwise cause corrosion and concrete deterioration.
"Impermeability to sulfates, chlorides, and other potentially harmful substances is a vital characteristic of concrete durability,” explains Cláudio Neves Ourives. “PENETRON ADMIX enhances concrete durability by reducing permeability and preventing the penetration of harmful substances by providing a self-healing capability that automatically seals hairline cracks in concrete for the lifetime of the structure.”