Abstract: A wastewater treatment system includes a tidal, sequential vertical flow marsh cell system having at least three marsh cells in serial forward fluid communication. Incoming wastewater to be treated is channeled to at least the first and a second marsh cell, and a portion of water exiting a final marsh cell, to the first marsh cell surface. Each marsh cell is alternately flooded and drained for enhancing aeration of incoming water and marsh cell contents, which include media and plant roots having biofilms growing thereon, the biofilms including a population of nitrifying and denitrifying bacteria, for achieving substantially simultaneous nitrification and denitrification of the wastewater.

Abstract: A wastewater treatment process integrates a tidal nitration system with a wastewater treatment lagoon. Raw effluent enters a lagoon having a persistent anoxic or anaerobic state and a long residence time to permit suspended solids to settle to the bottom, forming a blanket of sludge. Water above the sludge blanket is comparatively clearer than raw influent. Discharge from the clear water zone contains organic carbon, organic nitrogen, ammonia, and other nutrients. In the lagoon, complex carbohydrates and fats are broken down into simpler organic compounds by bacterial action, a substantial portion transformed to carbon dioxide by bacterial respiration, reducing BOD. Organic forms of nitrogen are transformed into ammonium ions by bacterial action. Adjacent to the lagoon is a sump that takes water from the clear zone to a tidal cell, and recycles water from the clear zone into the tidal cell, which then discharges back into the lagoon.

Abstract: The wastewater treatment systems have a plurality of treatment modules between the inlet and the outlet, each for treating water with a selected process. Influent is directed to a covered anaerobic reactor, and then to an attached growth pretreatment filter that is at least intermittently exposed to atmospheric oxygen. Following the filter is a hydroponic reactor followed by a vertical-flow wetland. A second embodiment includes, following the filter, a tidal vertical-flow wetland and a pump for recycling water exiting the wetland upstream of the filter.

Abstract: A wastewater treatment system includes a tidal, sequential vertical flow marsh cell system having at least three marsh cells in serial forward fluid communication. Incoming wastewater to be treated is channeled to at least the first and a second marsh cell, and a portion of water exiting a final marsh cell, to the first marsh cell surface. Each marsh cell is alternately flooded and drained for enhancing aeration of incoming water and marsh cell contents, which include media and plant roots having biofilms growing thereon, the biofilms including a population of nitrifying and denitrifying bacteria, for achieving substantially simultaneous nitrification and denitrification of the wastewater.

Abstract: A wastewater treatment system includes a vertical flow marsh cell that is adapted to contain media and to support plants having roots extending into the media, the roots and media positioned to contact water flowing downward through the marsh cell during a flooding stage, the media and plant roots providing surfaces to which biofilms can adsorb, the biofilms containing bacteria adapted to adsorb ammonium ions and nitrify ammonium ions to nitrate during an aerated drained phase. The marsh cell is configured to receive water from an outlet of a horizontal wetland that functions essentially anaerobically/anoxically to contain bacteria for transforming nitrate into nitrogen gas. Water to be treated and water exiting the marsh cell outlet are transportable to a wetland inlet, providing dilution of incoming wastewater. Treated water is discharged from the wetland outlet.

Abstract: The wastewater treatment system includes at least one fluidized bed reactor, such as a vessel containing media to which biofilms may attach. The vessel has an inlet and an outlet adjacent a bottom, and an overflow outlet adjacent a top, of the vessel. An element for admitting wastewater into the vessel and for agitating wastewater therein with sufficient energy to scour biofilm from the media, and for admitting additional wastewater into the vessel following a predetermined time to a level sufficient to cause water and at least some of the scoured biofilm to exit via the overflow outlet. Wastewater is drainable through the bottom outlet after a predetermined time for permitting aeration of the media. These fill and drain cycles effect a “tidal” nitrification and denitrification of the wastewater, with, for example, ammonia being converted ultimately to nitrogen gas.

Abstract: A wastewater treatment system includes a first lagoon having an inlet for receiving wastewater to be treated and a first vertical flow marsh cell having a bottom outlet. Water can be transported from the first lagoon to the first marsh cell. A second lagoon has an inlet for receiving water from the first marsh cell outlet and a second vertical flow marsh cell having a bottom outlet. Water can be transported from the second lagoon to the second marsh cell. At least a portion of the water exiting the second marsh cell outlet can be recycled to the first lagoon. The first and the second lagoon are adapted to function essentially aerobically and to contain plants having roots positioned to contact water flowing thereinto. The first and the second marsh cell are adapted to contain plants having roots positioned to contact water flowing thereinto.

Abstract: A wastewater treatment system includes a vertical flow marsh cell that is adapted to contain media and to support plants having roots extending into the media, the roots and media positioned to contact water flowing downward through the marsh cell during a flooding stage, the media and plant roots providing surfaces to which biofilms can adsorb, the biofilms containing bacteria adapted to adsorb ammonium ions and nitrify ammonium ions to nitrate during an aerated drained phase. The marsh cell is configured to receive water from an outlet of a horizontal wetland that functions essentially anaerobically/anoxically to contain bacteria for transforming nitrate into nitrogen gas. Water to be treated and water exiting the marsh cell outlet are transportable to a wetland inlet, providing dilution of incoming wastewater. Treated water is discharged from the wetland outlet.

Abstract: A wastewater treatment system includes a first lagoon having an inlet for receiving wastewater to be treated and a first vertical flow marsh cell having a bottom outlet. Water can be transported from the first lagoon to the first marsh cell. A second lagoon has an inlet for receiving water from the first marsh cell outlet and a second vertical flow marsh cell having a bottom outlet. Water can be transported from the second lagoon to the second marsh cell. At least a portion of the water exiting the second marsh cell outlet can be recycled to the first lagoon. The first and the second lagoon are adapted to function essentially aerobically and to contain plants having roots positioned to contact water flowing thereinto. The first and the second marsh cell are adapted to contain plants having roots positioned to contact water flowing thereinto.

Abstract: A wastewater treatment system includes a tidal, sequential vertical flow marsh cell system having at least three marsh cells in serial forward fluid communication. Incoming wastewater to be treated is channeled to at least the first and a second marsh cell, and a portion of water exiting a final marsh cell, to the first marsh cell surface. Each marsh cell is alternately flooded and drained for enhancing aeration of incoming water and marsh cell contents, which include media and plant roots having biofilms growing thereon, the biofilms including a population of nitrifying and denitrifying bacteria, for achieving substantially simultaneous nitrification and denitrification of the wastewater.

Abstract: The wastewater treatment systems have a plurality of treatment modules between the inlet and the outlet, each for treating water with a selected process. Influent is directed to a covered anaerobic reactor, and then to an attached growth pretreatment filter that is at least intermittently exposed to atmospheric oxygen. Following the filter are a first and a second hydroponic reactor in series, followed in turn by a vertical-flow wetland. A second embodiment includes, following the filter, two or more tidal vertical-flow wetlands in series, and a pump for recycling water exiting the final wetland upstream of the filter.

Abstract: The wastewater treatment systems have a plurality of treatment modules between the inlet and the outlet, each for treating water with a selected process. Influent is directed to a fixed-film reactor. Water then flows to a hydroponic reactor, in which aquatic plants are suspended atop the liquid for achieving aquatic-root-zone treatment. A filtration device removes any remaining suspended solids following the hydroponic reactor. Recycling may occur to the fixed-film reactor to enhance nitrogen removal from one or both of the hydroponic reactor and the filtration device.

Abstract: A wastewater treatment system includes a tidal, sequential vertical flow marsh cell system having at least three marsh cells in serial forward fluid communication. Incoming wastewater to be treated is channeled to at least the first and a second marsh cell, and a portion of water exiting a final marsh cell, to the first marsh cell surface. Each marsh cell is alternately flooded and drained for enhancing aeration of incoming water and marsh cell contents, which include media and plant roots having biofilms growing thereon, the biofilms including a population of nitrifying and denitrifying bacteria, for achieving substantially simultaneous nitrification and denitrification of the wastewater.

Abstract: A wastewater treatment system includes a first lagoon having an inlet for receiving wastewater to be treated and a first vertical flow marsh cell having a bottom outlet. Water can be transported from the first lagoon to the first marsh cell. A second lagoon has an inlet for receiving water from the first marsh cell outlet and a second vertical flow marsh cell having a bottom outlet. Water can be transported from the second lagoon to the second marsh cell. At least a portion of the water exiting the second marsh cell outlet can be recycled to the first lagoon. The first and the second lagoon are adapted to function essentially aerobically and to contain plants having roots positioned to contact water flowing thereinto. The first and the second marsh cell are adapted to contain plants having roots positioned to contact water flowing thereinto.

Abstract: The wastewater treatment systems have a plurality of treatment modules between the inlet and the outlet, each for treating water with a selected process. Influent is directed to a fixed-film reactor. Water then flows to a hydroponic reactor, in which aquatic plants are suspended atop the liquid for achieving aquatic-root-zone treatment. A filtration device removes any remaining suspended solids following the hydroponic reactor. Recycling may occur to the fixed-film reactor to enhance nitrogen removal from one or both of the hydroponic reactor and the filtration device.

Abstract: The wastewater treatment systems have a plurality of treatment modules between the inlet and the outlet, each for treating water with a selected process. Influent is directed to a covered anaerobic reactor, and then to an attached growth pretreatment filter that is at least intermittently exposed to atmospheric oxygen. Following the filter are a first and a second hydroponic reactor in series, followed in turn by a vertical-flow wetland. A second embodiment includes, following the filter, two or more tidal vertical-flow wetlands in series, and a pump for recycling water exiting the final wetland upstream of the filter.