To secure access to healthy water resources, efforts should be directed toward river remediation, real-time water quality monitoring, and related initiatives. Water quality analyzers are employed to monitor various aquatic parameters, ensuring the safety of water bodies. This paper focuses on exploring the application of chemical methods for river remediation, analyzed from the following two perspectives:

1.Chemical Algae Removal  

Chemical algae removal involves eliminating algal biomass in rivers through chemical interventions, primarily by adding chemical agents to disrupt colloidal structures in water and achieve algal elimination. Common strategies include chemical oxidation and algaecide-based treatments. Traditional algaecides such as potassium permanganate and copper salts are widely used; in recent years, natural flocculants have also been extensively researched and applied for this purpose. Key oxidants for algae removal include chlorine, chlorine dioxide, and hydrogen peroxide (H₂O₂).

While chemical algae removal processes are relatively simple, rapid, and highly operable, improper control of agent dosage during application may lead to adverse consequences—excessive dosing risks inducing secondary pollution.

2.Chemical Immobilization of Heavy Metals  

Heavy metals in river sediments can migrate into the water column under specific conditions, existing in bound or ionic forms. By introducing alkaline substances to elevate the pH of river water, heavy metals undergo precipitation reactions to form insoluble compounds (e.g., carbonates, silicates), which are then immobilized in sediments. Commonly used alkaline materials include calcium silicate slag. This method offers rapid efficacy and operational simplicity, effectively inhibiting the release of heavy metals into the water column in dissolved forms. However, excessive dosage must be avoided, as it may exert detrimental impacts on aquatic ecosystems.