Systems and methods for treating non-point source pollutants in water runoff using slow-release agents

A slow-release method of treating non-point source pollutants in water runoff with advanced oxidation processes (AOPs), including Fenton's reagent, as said runoff travels through a storm sewer system, comprising:

• providing a first slow-release AOP form including sodium percarbonate and sodium persulfate dispersed within a matrix;
• providing a second slow-release AOP form comprised of a matrix having dispersed therein one or more materials selected from the group consisting of ferrous sulfate heptahydrate, zero-valent iron, and other salts that produce reduced iron upon dissolution in water;
• placing at least one first slow-release AOP form together with at least one second slow-release AOP form in at least one or more inlets of the storm sewer system;
• and
• causing runoff water to contact the first and second slow-release form(s) as the water flows through the storm sewer system, thereby producing at least sulfate, and hydrogen peroxide and reduced irons (Fe0, Fe2+) that combine to produce Fenton's reagent, the sulfate and Fenton's reagent acting together to at least partially oxidize the pollutants in the runoff water.

A slow-release Fenton's reagent, comprising:

• a first slow-release form having sodium percarbonate dispersed within a matrix;
• and
• a second slow-release form having iron dispersed within a matrix;
• wherein, the first slow-release form and the second slow-release form are located in close proximity to one another so that, when concurrently exposed to a flow of water to be treated, the first slow-release form will slowly release hydrogen peroxide and the second slow-release form will supply reduced iron that will activate the hydrogen peroxide to produce Fenton's reagent.

A method of treating non-point source pollutants in water runoff using slow-release advanced oxidation process (SR-AOP) agents as said water runoff travels through a storm sewer system, comprising:

• providing a combination at least one persulfate SR-AOP form, at least one hydroxide SR-AOP form and at least one hydrogen peroxide SR-AOP form;
• placing the combination of forms in at least one or more inlets of the storm sewer system;
• and
• causing runoff water to collectively contact the combination of forms as it flows through the storm sewer system so as to at least partially oxidize the pollutants in the runoff water by slowly releasing persulfate, hydroxide and hydrogen peroxide thereto.

A slow-release advanced oxidation process water treatment system, comprising:

• a first slow-release form having sodium persulfate dispersed within a matrix;
• a second slow-release form having sodium hydroxide dispersed within a matrix;
• and
• a third slow-release form having hydrogen peroxide dispersed within a matrix;
• wherein, all of the slow-release forms are located in close proximity to one another so that, when concurrently exposed to a flow of water to be treated, the first slow-release form will slowly release persulfate, the second slow-release form will supply hydroxide ions to encourage the formation of sulfate radicals, and the third slow release form will supply hydrogen peroxide to enhance sulfate radical formation.