Water Quality in Industrial Systems
Understanding the pH-Algae connection is important in preserving and efficiently utilizing water resources as a global priority. Water quality plays a critical role in industrial settings, impacting operational efficiency, regulatory compliance, and environmental responsibility. Globally, harmful algal bloom occurrence has risen since the 1980s, including a 44% increase from the 2000s to 2010s, especially in Asia and Africa. Enhanced nutrient pollution owing to urbanization, wastewater discharge and agricultural expansion are key drivers of these increases. One often underestimated yet significant challenge in industrial water quality management is the interplay between algae and pH levels. Algae are directly related to pH levels, as the slightly alkaline condition provides optimal growth conditions for it. Consequently, high pH levels encourage excessive algae proliferation, leading to a range of problems in industrial water systems, including oxygen depletion and equipment corrosion.
Potential Hydrogen Explained
pH, or “potential hydrogen,” is a measure of the acidity or alkalinity in water, it plays a crucial role in industrial water management. It is a logarithmic scale that ranges from 0 to 14, with 7 being neutral, values below 7 indicating acidity, and values above 7 indicating alkalinity. Because many algae grow most abundantly at an alkaline pH, an attempt to reduce corrosion by raising the pH can lead to an algal bloom. Different species of algae prefer different pH ranges for optimal growth.
In the context of industrial water, maintaining the right pH level is critical. Water with extreme pH values can corrode pipes and equipment, leading to costly maintenance and reduced operational efficiency.
Managing Algae Blooms and pH in Industrial Water Systems
Many algae species, including green algae and blue-green algae, thrive in environments with increased pH, typically alkaline conditions. These algal blooms can lead to oxygen depletion and the production of unpleasant moldy odors, adversely affecting water quality in industrial aquatic systems.
The dynamic relationship between algae growth and pH changes is critical to monitor because elevated pH levels can lead to corrosion of equipment and pipelines, impacting industrial operations. Understanding how carbon dioxide dissolves in water and interacts with calcium carbonate and carbonic acid in aquatic systems helps explain these pH fluctuations. Chlorophyll and phycocyanin are key pigments that should be monitored for early detection of harmful algal blooms. For more on how carbon dioxide affects water chemistry, see EPA’s guide on pH in water.
Effective management of algae and pH requires continuous monitoring of water quality parameters such as pH levels, oxygen concentration, and nutrient availability. Industrial water systems often face challenges from harmful algal blooms, which can disrupt biological processes and threaten aquatic life. Moreover, dissolved oxygen levels decrease as algal blooms die off and are degraded by bacteria. This leads to suffocation of aquatic life. Therefore, maintaining the buffering capacity of water bodies and controlling nutrient inputs, including total nitrogen and dissolved organic carbon, are essential strategies.
How to Keep pH and Algae in Check?
Monitoring and controlling pH levels is essential to prevent excessive algae growth and maintain optimal water quality in industrial aquatic systems. Algae effect on pH is significant because as algae grow, they consume carbon dioxide, which reduces hydrogen ion concentration and causes pH to rise, often leading to alkaline conditions. Such algae-driven pH fluctuations can have adverse effects on equipment, aquatic life, and regulatory compliance.
The raipd growth of algae can push pH levels beyond the permissible limits set by regulatory bodies such as the National Pollutant Discharge Elimination System (NPDES). Exceeding these limits not only risks fines and legal penalties but can also lead to operational shutdowns if discharge permits are violated. Moreover, high pH levels contribute to corrosion of pipes and machinery, increasing maintenance costs and shortening equipment lifespan.
Maintaining a neutral pH or slightly alkaline conditions is important because most species of algae and aquatic plants thrive within specific pH ranges. For example, freshwater systems typically favor a pH near 7.0, while marine algae prefer slightly higher pH values around 8.2. Deviations from these environmental conditions can reduce species richness and disrupt the balance of other organisms in the water column.
The Overall Water Chemistry
Water chemistry plays a fundamental role in regulating aquatic systems. The balance of nutrients, dissolved inorganic carbon species, acidic conditions and buffering capacity directly influences the chemical environment where algae thrive. Nutrients such as nitrogen and phosphorus serve as critical drivers of algal blooms. This fuels the rapid growth that alters the water’s chemical composition. During photosynthesis, algae consume carbon dioxide, which reduces the concentration of hydrogen ions. This causes the pH to rise, often leading to alkaline conditions. This shift in pH affects the speciation of dissolved inorganic carbon, including carbon dioxide, bicarbonate and carbonate ions, each of which plays a distinct role in algal metabolism. For instance, at lower pH values, carbon dioxide is the dominant form available for photosynthesis. Whereas at higher pH, bicarbonate becomes more prevalent, and carbonate dominates in highly alkaline waters. The water’s buffering capacity, largely determined by the presence of calcium carbonate and other minerals, helps moderate pH fluctuations by neutralizing excess hydrogen or hydroxide ions. However, when nutrient inputs are excessive, this buffering system can be overwhelmed, resulting in significant and rapid pH changes that disrupt aquatic life and water quality.
The Last Resort
Chemical treatments may be used as a last resort but have drawbacks including potential adverse effects on aquatic life, the risk of algae die-off causing oxygen depletion, and environmental contamination. Many freshwater systems use chemical treatments for several species of algal blooms. However, overtime, algal blooms get used to the same treatment methods and hence, become resistant. Therefore, industries are increasingly adopting sustainable and preventive approaches. Those that can address algae growth before it escalates, helping to maintain water quality and preventing fish kills associated with oxygen depletion during algae die-off.
In summary, understanding the algae effect on pH and its observed effects on aquatic systems is vital for industrial water management. By maintaining balanced environmental conditions and monitoring key parameters, industries can prevent significant changes in pH, protect aquatic life, comply with drinking water and discharge regulations, and ensure the long-term sustainability of their water bodies.
Better Solutions than Chemicals
As mentioned, chemical treatments are effective short term and offer fast results, yet they kill the algae only after they’ve grown and caused problems. They need to be frequently dosed and aren’t environmentally safe. Also, chemicals may cause corrosion and other problems within a water treatment plant. Some may even raise pH levels. Additionally, reliance on chemical treatments can lead to the development of resistant algae bloom strains, making long-term control more challenging. The environmental impact of chemical runoff can affect surrounding ecosystems, harming beneficial aquatic organisms and disrupting the natural balance. Therefore, industries are seeking sustainable and preventive solutions that address algae growth.
Real-world Applications
Understanding the pH-algae connection is vital, but how does it translate into real-world applications within industrial settings? Let’s take a closer look at Power generation facilities as an example. Cooling ponds play a crucial role in power generation, but excessive algae growth can push pH levels beyond permissible limits. To comply with regulations, power plants must implement strategies to manage algae and adjust pH levels before discharging cooling water.
NIPSCO, a power plant in the United States, successfully implemented the ultrasound solutions in their reservoir. NIPSCO uses a large reservoir for settling out suspended solids prior to discharging the water back to the Kankakee River. This water is rich in nutrients, causing algae to grow at an undesired rate. Algae has a direct effect on pH and TSS levels in water. NIPSCO’s main goal was to reduce TSS levels to comply with NPDES Regulatory Discharge Limits. After installing ultrasonic technology, they managed to reduce algaecide and eliminated a UV Blocker chemical from their treatment program. This resulted in improved water quality and a positive environmental impact.
Conclusion
In industrial water management, understanding the connection between pH levels and algae is crucial. As we’ve seen, maintaining the balance between pH and algae growth can prevent equipment damage. Which also reduces maintenance costs, ensures regulatory compliance, and protect the environment. By embracing advanced technologies and proactive strategies, industries can navigate this dynamic relationship. Which also ensures the health and sustainability of their water systems while simultaneously advancing their operational goals.
Learn more from our case studies on algal bloom management.