Using Ozone Nanobubbles to Eliminate Algae Blooms and Cyanobacteria from Water Bodies
Water Reservoirs in Israel and Their Challenges
In many regions of Israel, water reservoirs fed by runoff and treated wastewater at varying levels can be found. These reservoirs, which are replenished every winter by runoff water and throughout the year by treated wastewater from municipal wastewater treatment plants, serve as an important water source for agriculture in Israel. The benefits of these reservoirs lie in their ability to address the issue of treated wastewater disposal, reduce pollution of rivers and groundwater, and provide a stable and reliable water source for farmers seeking alternative water supplies to freshwater.
Algae Blooms in Reservoirs
However, there is a drawback. The high nutrient concentrations in these reservoirs create fertile ground for the development of algae and cyanobacteria (phytoplankton), which sometimes reach high concentrations and result in “blooms.” These blooms are characterized by high levels of suspended biological material, high turbidity, and a greenish hue in the water. In some cases, when certain cyanobacteria species dominate the phytoplankton population, floating mats may develop, drifting with the wind and surface waves. Over time, the phytoplankton bloom may decline due to the growth of zooplankton populations, which feed on algae.
This unusual population dynamic poses a challenge for water supply systems for agriculture, as removing suspended matter from the water is essential to ensure the proper functioning of drip and irrigation systems in orchards and agricultural fields. Advanced filtration systems installed on water intake lines are designed to remove suspended materials. However, when algae concentrations are high and blooming species form colonies with numerous cells, the filtration systems frequently clog, leading to increased filtration and maintenance costs.
Treating Water for Agricultural Irrigation
The treatment of reservoir water used for agricultural irrigation aims to reduce algae and cyanobacteria populations, lower concentrations of suspended solids, improve filtration efficiency, and prevent clogs in irrigation systems. In Israel and worldwide, various treatment approaches have been developed, tested, and implemented to control and mitigate extreme algae and cyanobacteria bloom events. These include removing biomass, employing physical methods for biomass collection, and applying direct chemical treatments.
While common herbicides such as copper sulfate, diuron, or endothall are available for controlling algae and cyanobacteria blooms in reservoirs, their use is limited due to their adverse effects on the broader aquatic ecosystem. The recommended approach involves using oxidizers like hydrogen peroxide or ozone, which specifically inhibit cyanobacteria growth with minimal impact on other populations in the system. The advantage of these oxidizers is their selective targeting of cyanobacteria with minimal effects on algae and zooplankton. Additionally, they are biodegradable and do not persist in the environment.
What Are Ozone Nanobubbles, and How Do They Work?
An innovative technology recently tested and applied for treating algae and cyanobacteria blooms in water bodies is based on ozone nanobubbles (NBO3). Nanobubbles are microscopic gas bubbles with diameters smaller than 200 nanometers. Ozone nanobubbles contain ozone gas, a powerful oxidizer that is effective in breaking down organic pollutants and is known for its antibacterial, antiviral, and algae-destroying properties.
Ozone is typically produced on-site using an ozone generator that converts oxygen from the air into ozone through high-voltage electricity. Due to the high surface-to-volume ratio of nanobubbles, ozone transfer into the water is more efficient. Additionally, the bubbles are stable in water and remain active for extended periods. Their tiny size increases the contact area with algae cells, enabling effective oxidation that collapses algae cells and reduces their population.
The combination of nanobubble technology and ozone treatment can significantly reduce algae populations, including harmful species, increase dissolved oxygen levels in the water, and enhance filtration efficiency while maintaining a healthy ecosystem. Unlike some chemical treatments, ozone nanobubble treatment is environmentally friendly and does not leave harmful residues.
NANO+ NBO3 Systems: A Tailored Solution
NANO+ develops floating systems tailored for agricultural water reservoirs. Beyond its extensive experience in manufacturing and supplying NBO3 systems for water and wastewater treatment, NANO+ offers unique advantages with its proprietary nanobubble generators. These generators are configured to meet specific customer needs.
Floating NANO+ systems have been installed in several wastewater reservoirs used for agriculture. At this stage, the operation of these systems is supported by technical expertise, specialized equipment, and monitoring systems that track water quality and treatment efficiency, ensuring the client’s objectives are met.
If you’re interested in using the NBO3 system to control and manage algae and cyanobacteria blooms in irrigation water reservoirs, consult our experts, who are knowledgeable in nanobubble technology. Treatment effectiveness may vary depending on the specific characteristics of the water body (e.g., size, algae types, environmental conditions). Therefore, an initial assessment of water quality is recommended to understand the reservoir’s unique challenges and customize the system accordingly.
