Environmental Testing & Water Testing Laboratory for Industries

With state-of-the-art technology and technical expertise, EP Aqua carried out a treatability study to optimize effluent treatment at a major automotive company.

The Challenge

A large company in the sector was faced with the challenge of reducing the concentration of phosphorus in its industrial effluents, in compliance with the environmental limit of 0.1 mg/L. To do this, it enlisted the support of EP, a benchmark in environmental solutions, which carried out a complete technical study focusing on the efficiency and sustainability of the process.

Meeting the demanding phosphorus removal target in a complex industrial environment required more than conventional treatment.

Did you know?

The concentration levels of phosphorous in wastewater can vary throughout the U.S.?

The total phosphorus effluent limits are issued in regions throughout the U.S., and some areas are beginning to achieve ultra-low limits below 0.1 mg/L T.P. 

The EP Aqua Solution

EP applied a methodology based on thorough treatability tests, using the JAR-TEST method to simulate and optimize each stage of the process. The strategy included:

• Coagulation with Poly Aluminum Chloride (PAC)
• Flocculation for efficient floc formation
• Safe removal of generated sludge

In addition, different tests were carried out with samples, simulating critical scenarios to ensure the robustness of the proposed solution.

Significant results

The reduction in the dosage of phosphorus, which was previously much higher than the amount allowed by the regulations, was reduced to practically zero.

The solution was improved with adjustments that significantly increased treatment efficiency, guaranteeing a clearer final effluent that met the required standards. The performance achieved is the result of a combination of good operating practices and applied technical knowledge.

Commitment to sustainability

With the solution applied, the company achieved compliance with current environmental standards and strengthened its commitment to sustainability. The study reaffirms EP Engenharia’s ability to offer tailor-made solutions, based on data and technical tests, for the most diverse challenges in the industrial sector.

More about EP Aqua:

With over 50 years’ experience in the environmental sector, EP iAqua is company that is a benchmark in integrated solutions for the treatment of water, effluents and reuse, serving industries, environmental consultancies and sanitation operators.

Through the 360° Solution, we offer a complete and centralized model, capable of uniting all stages of the environmental process – from initial analysis to full system operation – with high efficiency, safety and standardization.

Recognized for its personalized approach and focus on innovation, EP Aqua delivers everything from treatability studies to the ongoing operation of sustainable systems, adapting each project to the technical and regulatory needs of its clients.

Operating throughout Brazil and now expanding internationally, including to the United States, EP AQUA is prepared to meet the demands of different sizes and sectors, offering flexibility, scalability and excellence in every delivery.

Context and Objective:

Goodyear, one of the world’s largest tire manufacturers, faced challenges with the wastewater generated from its operations, primarily composed of three types: Boiler Blowdown, Oily Water, and Soapy Water. These effluents were not compliant with the disposal requirements of Article 15 of Decree 6067/12. The objective of the study, conducted by EP Engenharia, was to perform treatability tests to reduce contaminants, enable legal disposal, and explore possibilities for water reuse.

Characterization of the Effluents:

• Boiler Blowdown: pH 11.6; COD of 468.5 mg/L.
• Oily Water: COD of 787 mg/L; Total Solids of 1,872 mg/L.
• Soapy Water: The most challenging, with COD of 3,878 mg/L and Total Solids of 10,344 mg/L.

Treatability Tests:

bench-scale tests were performed using advanced oxidation processes (AOP) and pH adjustments to assess the removal of organic load (COD) and total solids.

1. Boiler Blowdown: treatment reduced the COD from 468.5 mg/L to 44.6 mg/L, falling within the permitted limit (600 mg/L).
2. Oily Water: treatment was less effective, with COD reduced to 960.5 mg/L, exceeding the legal limit.
3. Soapy Water: this effluent showed low treatability due to its complex physical-chemical characteristics, and external treatment was recommended.

Conclusion:

despite improvements in the treatment of Boiler Blowdown and Oily Water, the effluents did not fully meet all legal disposal parameters. For reuse, additional treatment steps, such as filtration and reverse osmosis, would be required. Soapy Water, due to its complexity, was recommended for external treatment.

Context and Objective:

Mars Guararema’s industrial plant required a technical consultancy to assess the effluent treatment system and ensure compliance with CONAMA Resolutions 357/05 and 430/11, as well as State Decree 8468/76. The main objective was to align the effluent discharge with the regulations for Class 2 water bodies and explore possibilities for reusing treated effluent within the factory.

Initial Effluent Characterization:

effluent samples were collected from various stages of the treatment process, including raw effluent, flotation, anaerobic treatment, aerobic treatment, and final output. The raw effluent presented the following characteristics:

• pH: 4.5
• Total Dissolved Solids (TDS): 1,950 mg/L
• Biochemical Oxygen Demand (BOD): 19,997 mg/L
• Dissolved Iron: 23.95 mg/L.

Study of Treatability:

the study explored several treatment methods to achieve compliance:

1. Color Removal:

→ Sodium hypochlorite (12%) was used to remove color from the effluent. Tests showed that a dosage of 0.04 mL per 500 mL of effluent effectively eliminated color with a contact time of 30 minutes.

2. Free Chlorine Removal:

→ A pilot test using activated carbon filtration demonstrated effective free chlorine removal. After treatment, the effluent showed a chlorine level below 0.01 mg/L, meeting regulatory limits.

3. Phosphorus Removal:

○ The use of aluminum polychloride (PAC) and hydrochloric acid (HCl) helped reduce phosphorus levels to less than 0.05 mg/L, meeting legal requirements for effluent discharge.

4. BOD Reduction:

○ Chlorination followed by activated carbon filtration resulted in a reduction of BOD from 101 mg/L to 4 mg/L, ensuring compliance with CONAMA 357/05.

Implementation of Reverse Osmosis:

to meet the strict standards for Total Dissolved Solids (TDS), the study recommended the installation of a reverse osmosis (RO) system. The proposed system would produce permeate with a TDS of 107 mg/L, suitable for reuse, while the reject stream would contain higher concentrations of dissolved solids.

Conclusions:

the study concluded that Mars Guararema’s effluent treatment system could be optimized with chemical precipitation for phosphorus, sodium hypochlorite for color removal, activated carbon for chlorine removal, and reverse osmosis for TDS reduction. The treated effluent could potentially be reused within the factory, reducing water consumption and improving sustainability.

Recommendations:

• Odor Control: the report suggests consulting a specialized company to evaluate the best technique for controlling odor emissions, such as condensation or activated carbon adsorption.
• Cost Estimates: the reverse osmosis system is estimated to cost between R$ 600,000 and R$ 1,000,000, while other components, such as activated carbon filters and evaporation systems, add to the total investment

Context and Objective:

IFF Essências e Fragrâncias, located in Taubaté (SP), requested a

treatability study for the wastewater generated from its production processes. The objective was to reduce contaminant levels such as Chemical Oxygen Demand (COD) and oils and greases, improving treatment efficiency and ensuring compliance with Decree 8468/78, which regulates wastewater discharge.

Wastewater Characterization:

initial characterization of the effluent revealed that the levels of oils and greases, as well as COD, exceeded the regulatory limits:

Oils and Greases: 63.5 mg/L (limit of 5 mg/L).

• COD: 4128 mg/L.

Treatability Study: the treatability study was conducted using coagulation and flocculation with Aluminum Polychloride (PAC 18%) and Anionic Polymer (0.2%), applied in jar tests to assess the efficiency in reducing turbidity and COD.

1. General Washing Effluent:

→ The optimal PAC dosage was 0.2 mL/200 mL, resulting in a significant reduction in COD from 12035 mg/L to 3137 mg/L (74% removal).

2. Cocoa Washing Effluent:

→ A composition of 80% effluent mixed with general washing water showed the best efficiency, reducing COD from 13030 mg/L to 6054 mg/L (53% removal).

3. Cheese Washing Effluent:

→ Tests with 80% effluent resulted in COD reduction from 10585 mg/L to 3761 mg/L (64% removal).

4. Chicken Washing Effluent:

→ The 60% effluent mixture demonstrated the highest efficiency, reducing COD from 11930 mg/L to 4238 mg/L (64% removal).

Conclusion:

based on the results, it was recommended to implement an enhanced treatment system consisting of an anaerobic UASB reactor and an activated sludge system to ensure greater efficiency in removing organic load, COD, and oils and greases. Additionally, automating the chemical dosing system, such as for alkalizing agents, was suggested to improve operational control.

Context and Objective:

the General Motors (GM) plant in São José dos Campos requested a technical study to optimize its effluent treatment system, focusing on the removal of phosphorus. EP Engenharia was tasked with conducting treatability tests to ensure compliance with environmental standards, aiming to reduce total phosphorus concentration to less than 0.1 mg/L, as required by current regulations.

Methodology:

the treatment process involved chemical phosphorus removal using Aluminum Polychloride (PAC) as the primary coagulant. The bench-scale tests followed the JAR-TEST method, which included the following steps:

1. Rapid coagulation with PAC.
2. Slow flocculation for the formation of flocs.
3. Sedimentation for sludge removal.

Sample Collection and Characterization:

effluent samples were collected at different stages of the treatment process for analysis. Initial phosphorus levels ranged from 2.291 mg/L to 2.494 mg/L. Additional samples were enriched with phosphorus (ranging from 6 mg/L to 12 mg/L) to simulate extreme conditions.

Treatability Tests:

several tests were conducted to identify the optimal PAC dosage and operational conditions:

1. PAC Dosage Tests:

→ Dosages ranging from 1 mL to 6 mL of PAC per liter of effluent were tested. The dosage of 3 mL/L showed the best efficiency, reducing phosphorus levels to 0.0111 mg/L.

2. Tests with Anionic Polymer:

→ The combination of PAC with an anionic polymer was tested to optimize floc formation and sedimentation. The polymer improved effluent clarification, reducing both turbidity and phosphorus levels.

3. Mixing Speed and Flocculation Time:

→ Different mixing speeds (300 s−1 to 600 s−1) and flocculation times were tested. The best results were obtained with a mixing speed of 500 s−1 and flocculation at 60 s−1 for 10 minutes, reducing phosphorus to levels below 0.015 mg/L.

Conclusion:

the treatability study conducted by EP Engenharia demonstrated that efficient phosphorus removal from GM’s treated effluent was achieved using a combination of PAC and anionic polymer, along with optimized control of coagulation and flocculation stages. The reduction of total phosphorus to levels below 0.1 mg/L ensured compliance with environmental regulations, supporting the sustainable and continuous operation of the GM plant.

Context and Objective:

Volkswagen Truck & Bus, located in Resende (RJ), contracted EP Engenharia to conduct a treatability study of the water used in its industrial process. The primary objective was to ensure compliance with the parameters for total iron and apparent color set by Portaria GM/MS No 888, of May 4, 2021, which regulates potable water standards.

Initial Characterization:

water samples were collected from five points: Well 2, Well 6, raw water outlet, sand filter outlet, and the sink. Initial characterization revealed values exceeding the permissible limits for total iron and apparent color, especially in Well 6, which showed total iron of 4.176 mg/L, far above the allowed limit of 0.3 mg/L, and apparent color of 42.5 mg Pt-Co/L, also exceeding the limit of 15 mg Pt-Co.

Methodology:

the treatment involved a combination of chemical oxidation using sodium hypochlorite and activated carbon filtration. Several tests were conducted, adjusting sodium hypochlorite dosages and reaction times to optimize contaminant removal.

Treatability Tests:

1. Well 6: the initial treatment with sodium hypochlorite reduced total iron by 89.08%, reaching 0.456 mg/L, though still above the required limit. The apparent color removal was 12%, indicating the need for further optimization.

2. Well 2: the results were more promising, with total iron reduced by 77.68%, achieving 0.283 mg/L, within the allowed limit. The apparent color, being below the initial limit, showed little variation.
3. Raw Water Outlet: after treatment with sodium hypochlorite and filtration using activated carbon, total iron was reduced by 83.77%, reaching 0.231 mg/L, and apparent color was reduced by 75.25%, within the permitted limit.

4. Sand Filter Outlet: treatment at the sand filter outlet produced consistent results, with total iron reduced by 52.12% and complete removal of apparent color. This indicated the effectiveness of filtration combined with chemical oxidation.

Pilot Unit Operation:

a Pilot Unit operation was conducted to validate the results on an industrial scale. The activated carbon filter demonstrated efficiency in removing residual chlorine, total iron, and apparent color. Final results showed an apparent color of 3 mgPt-Co/L and total iron of 0.131 mg/L, both within the required limits.

Conclusion:

The treatability study conducted by EP Engenharia demonstrated that the oxidation process using sodium hypochlorite, combined with activated carbon and sand filtration was effective in removing total iron and apparent color. The results were satisfactory, meeting the potable water standards defined by current legislation. The success of this study highlights the feasibility of implementing these technologies to ensure water quality at Volkswagen Truck & Bus’s facility.