21754 results about "Wastewater disposal" patented technology

The invention relates to a catalysis and micro-electrolysis combined technology for high-concentration refractory organic wastewater; the organic wastewater is collected to an adjusting tank and enters an air floatation tank for air floatation treatment to remove part of the organic matters after the adjustment of water volume and water quality; the scruff is collected or recovered; the wastewatergoes through Ph adjustment and then enters a catalytic iron-carbon and micro-electrolysis unit to improve the biochemical quality; the effluent goes through Ph adjustment and then enters a sedimentation tank; the effluent of the sedimentation tank adopts anoxic-aerobic biochemistry treatment to remove the organic matters and ammonia nitrogen and then is emitted after reaching the standard; and the filler of the catalytic iron-carbon and micro-electrolysis unit comprises iron, carbon and a catalyst, wherein the mass ratio of the iron, carbon and catalyst is 1: (0.3-1.5): (0.01-0.5). The invention can effectively improve the micro-electrolysis electrochemical reaction efficiency and the degrading capability to the organic matters, and reduce the wastewater treatment cost with convenient technological operation.

The invention is directed to a method and apparatus for treating wastewater. The wastewater treatment system includes a bioreactor including activated carbon and a first biological population. The wastewater treatment system may also include a membrane bioreactor and / or a wet oxidation unit.

Methods and systems for a subsurface upflow wetland for wastewater treatment that includes a series of parallel treatment cells, each cell including from bottom to top, a layer of gravel, a layer of sand over the gravel to remove pathogens from a septic effluent, a pollution control medium above the sand layer to remove nutrients, total suspended solid, and biochemical oxygen demand and a growth media mixture layered on top of the pollution control media to grow plants, and a gravity distribution system to distribute effluent to the series of parallel treatment cells. The pollution control medium includes at least one recycled material and at least one naturally occurring material. In an embodiment it includes recycled tire crumb, sand and limestone or recycled tire crumb, compost, sand and limestone.

Contaminated wastewaters comprising biochemical oxygen demand (BOD), nitrogen and phosphorus are treated by an activated sludge process. The process utilizes an activated sludge tank, a solid-liquid separator, and a bioreactor to significantly reduce, or eliminate, waste activated sludge (WAS) within a sludge stream. A sidestream reactor is employed downstream from the bioreactor to remove soluble phosphates left in the sludge stream by the low WAS process. Within the sidestream reactor, a source of multivalent metal ions is added to a slightly alkaline sludge stream to precipitate the phosphates. The solid phosphates have a specific gravity higher than that of the organic matter in the sludge stream and may be separated from the sludge stream based upon differential settling velocity.

A method and process for the treatment of wastewater containing phosphorous and nitrogen. The wastewater is first anaerobically treated to produce an anaerobic effluent from which insoluble organic carbon is separated to form a sludge rich in organic carbon that is used as a substrate during anoxic treatment of the wastewater by de-nitrifying phosphorous accumulating organisms (DPAO's) and ordinary de-nitrifying organisms. The separation of insoluble organic carbon is normally conducted using a clarifier located intermediate the anaerobic and anoxic bio-reactors. In one embodiment, the ammonia rich clarifier supernatant is directed to an aerobic reactor for nitrification and the nitrate produced is recycled to the anoxic bio-reactor. The final effluent may be membrane filtered to retain nitrifying biomass within the aerobic bio-reactor. The invention reduces overall hydraulic residence time and sludge volume, which results in a smaller, less expensive wastewater treatment system.

The invention relates to a method for preparing a graphite-phase carbon nitride (g-C3N4) material. The method includes the steps that a carbon nitride precursor and ammonium salt are evenly mixed, and then calcination is conducted so that the porous g-C3N4 material can be obtained. The ammonium salt is any one of ammonium base salts capable of generating ammonia gas through thermal decomposition or is the combination of at least two of the ammonium base salts. In the preparation process of the g-C3N4 material, the ammonium salt is added into the carbon nitride precursor to be mixed. In the high-temperature calcining process, the ammonium salt is subjected to pyrogenic decomposition to generate gas, a pore-forming effect on the g-C3N4 material is achieved, and the cellular porous g-C3N4 material is obtained. In the preparation process of the g-C3N4 material, template agents are not used, and thus the method is simple, efficient and environmentally friendly; the prepared g-C3N4 material is high in photocatalytic activity and can be used in the pollution control processes such as exhaust gas and wastewater treatment.

A computer system linked by the internet to various remote waste water treatment facilities. The system receives real-time data from the facilities and analyzing the data to determine likely operational upsets and future effluent water quality. The computer system sends signals to a hierarchy of parties depending on the severity of predicted upsets problems and events. The computer also provides a probability distribution of such upsets and water quality and recommendations as how to adjust facility operating parameters to avoid or reduce the upsets to acceptable parameters and maintain effluent water quality parameters within preselected limits.

A wastewater treatment system is provided that includes first and second reactors, each operative to nitrify or denitrify wastewater contained therein. Downstream from the first and second reactors is a membrane reactor that operates under aerobic conditions and includes one or more submersed membranes for separating solids. Extending between the membrane reactor and each of the first and second reactors is a return activated sludge line with appropriate controls for permitting return activated sludge to be directed to one of the reactors at a time. To nitrify and denitrify wastewater, a wastewater influent stream is alternatively directed to the anoxic reactors which are alternatively operated under aerobic and anoxic conditions so as to nitrify or denitrify the wastewater contained therein. To reduce or minimize the dissolved oxygen return from the membrane reactor to the first and second reactors, the flow of return activated sludge is controlled such that generally return activated sludge is returned to the reactor operating under aerobic conditions.

An inter-zone aerobic to anoxic zone flow rate control system for single vessel multi-zone bioreactor plants for wastewater treatment is described herein. The system of the invention provides control of the relative treatment times of the mixed liquor in the horizontally disposed and adjacent aerobic and anoxic treatment zones of the bioreactor by providing one or more flow rate adjusting gates located between the aerobic and anoxic zones of the bioreactor. The opening of the gates is adjustable in accordance with sensed conditions in the treatment zones. An automated embodiment of the invention includes a programmable logic controller that provides control scripts for adjusting the opening of one or more flow control gates according to inputs from sensors and per programmed instructions. An automated and supervised embodiment of the invention includes a computer interfaced with a programmable automating controller. The computer provides status reports, commands to the programmable automating controller, storage and analysis of data, as well as a means of communicating to remote monitoring centers and networks.

A simple yet effective and robust identification method is presented using process step responses for process identification that can provide a continuous transfer function with time-delay without iteration. A cascade relay provides accurate and reliable more points on the process frequency response. The internal model principle is employed to design single-loop controller of PID or high-order types with best achievable control performance for controller tuning, e.g. both single and multivariable cases are covered. The process identification and control design portions can be easily integrated into a control system auto-tuning package. Further, a general control scheme for disturbance rejection is given which can significantly improve disturbance rejection performance over conventional feedback systems with time delays. Practical issues such as noises, real-time implementation and tuning guidelines are also provided. The present invention provide general, systematic, effective, and applicable methods for process identification and control for a wide range of industries such as process and chemical plants, food processing, waste water treatment and environmental systems, oil refinery, servo and mechatronic systems, where a system model is needed for analysis, prediction, filtering, optimization and management, and / or where control or better control is required for their systems.

This is a method of filtration of a liquid comprising steps of sequential filtration of said liquid through at least one deep bed medium producing at least one first filtrate followed by at least one membrane medium filtration producing at least one second filtrate, wherein said membrane medium is at least periodically within said deep bed media Many types of deep bed and membrane media can be used. The domain of using contact clarification (direct filtration) can be expanded towards greater solids concentration. Operation and backwash, is simplified, continuous filtration becomes possible. Water can be water from natural source water, process water, wastewater, aqueous or non-aqueous suspensions, emulsions, solutions. Treatment can include mechanical interception of suspended particles, chemical, physical chemical, electrochemical, and biological processes. In water and wastewater processing, control over suspended solids, BOD, COD, nitrogen and phosphorus compounds, bacteria and viruses, heavy metals, color, and other constituents can be dramatically improved as compared to conventional processes. The method can be accommodated in new and modified existing treatment systems.

Wastewater treatment systems and processes for: removal of solids, pathogens, nitrogen, and phosphorus from municipal and agricultural wastewater include nitrification of wastewater and increasing the pH of the nitrified wastewater by adding a metallic-containing salt and hydroxide to precipitate phosphorus to form a useable effluent having a specified nitrogen:phosphorus ratio that is useful as a fertilizer or spray for remediation of contaminated soils. The presence of infectious microorganism such as enteropathogenic bacteria and picarnoviruses will be reduced in the useable effluent. The precipitated phosphorus is recovered and used to form useable phosphorus products.

Disclosed are: a catalyst which can exhibit an excellent catalytic activity and excellent durability for a long period in the wet oxidation treatment of waste water; a wet oxidation treatment method for waste water using the catalyst; and a novel method for treating waste water containing a nitrogenated compound, in which a catalyst to be used has a lower catalytic cost, the waste water containing the nitrogenated compound can be treated at high purification performance, and the high purification performance can be maintained. The catalyst for use in the treatment of waste water comprises an oxide of at least one element selected from the group consisting of iron, titanium, silicon, aluminum, zirconium and cerium as a component (A) and at least one element selected from the group consisting of silver, gold, platinum, palladium, rhodium, ruthenium and iridium as a component (B), wherein at least 70 mass% of the component (B) is present in a region positioned within 1000 [mu]m from the outer surface of the component (A) (i.e., the oxide), the component (B) has an average particle diameter of 0.5 to 20 nm, and the solid acid content in the component (A) (i.e., the oxide) is 0.20 mmol / g or more. The waste water treatment method uses a catalyst (a pre-catalyst) which is placed on an upstream side of the direction of the flow of the waste water and can convert the nitrogenated compound contained in the waste water into ammoniacal nitrogen in the presence of an oxidizing agent at a temperature of not lower than 100 DEG C and lower than 370 DEG C under a pressure at which the waste water can remain in a liquid state and a downstream-side catalyst (a post-catalyst) which is placed downstream of the direction of the flow of the waste water and can treat the waste water containing ammoniacal nitrogen.

The invention proposes a processing technology of heterocatalysis persulfate Fenton oxidation water. In the method, transitional metal, transitional metallic oxide and a transitional metal / transitional metallic oxide composite material are used as out-phase Fenton reagents; and persulfate is catalyzed and decomposed to generate hydroxyl radical free radical, thus oxidizing to remove the organic matters in the waste water. Compared with the water treatment technique of homogeneous phase persulfate, the out-phase transitional metal and the transition metal oxide catalyst can slowly release transitional metal icons, thus ensuring that the organic matters in the water are purified lastingly and efficiently by the processing method of the heterocatalysis persulfate Fenton oxidation water. The processing technology of heterocatalysis persulfate Fenton catalyzed oxidation water built by the invention is suitable for processing various organic wastewater, has the advantages of good durability, high efficiency, environmentally friendliness, and no secondary pollution, is easy to operate, conforms to the requirements of actual water treatment units, and has great application potential in the field of environmental pollution regulation.

The invention discloses a treatment method of high saline wastewater, and relates to the treatment technology. The method comprises the following steps: preparing high saline wastewater, regulating in a regulating pond, chemically pre-treating in a settling pond, filtering in a V-shaped filter pond, the first section ion exchange softening, ultrafiltering in an ultrafiltration system, reverse osmosis treating through a first section reverse osmosis system, the second ion exchange softening, nano-filtering through a high-pressure nano-filtration system, nano-filtering to produce water, reverse osmosis treating through a second section reverse osmosis system, concentrating through a first section high-pressure flat film system, MVR evaporating and crystallizing to obtain the industrial level sodium chloride; nano-filtering to concentrate water, concentrating through a second section high pressure flat film system, freezing and crystallizing to obtain the industrial level mirabilite. The ultra-filtration, the nano-filtration, the reverse osmosis and high-pressure flat film methods are reasonably coupled to combine with the MVR crystallization and freezing crystallization to treat the high saline wastewater, the defect of single technology is overcome, the combination advantage is developed, the problems of efficiently and economically treating and recycling the high saline wastewater can be solved, and the treatment method has obvious economic benefit and social benefit.

In a wastewater treatment system and process utilizing membrane bioreactors (MBRs), multiple, parallel series of tanks or stages each include, an MBR stage. Under conditions of normal flow volume into the system, influent passes through several parallel series of stages or process lines, which might be, for example, an anoxic stage, an aeration stage and an MBR stage. From the MBR stages a portion of M.L.S.S. is cycled through one or more thickening MBRs of similar process lines, for further thickening and further processing and digesting of the sludge, while a majority portion of the M.L.S.S. is recycled back into the main process lines. During peak flow conditions, such as storm conditions in a combined storm water / wastewater system, all of the series of stages with their thickening MBRs are operated in parallel to accept the peak flow, which is more than twice normal flow. M.L.S.S. is recycled from all MBR stages to the upstream end of each of all the parallel process lines, mixing with influent wastewater, and the last one or several process lines no longer act to digest the sludge. Another advantage is that with the thickened sludge in the last process line of basins, which ordinally act to digest the sludge, there is always sufficient biomass in the system to handle peak flow, the biomass being available if needed for a sudden heavy flow or an event that might bring a toxic condition into the main basins.

The invention discloses a preparation method of a catalytic wet oxidation catalyst and a treatment method of organic wastewater. The preparation method comprises the following steps of: (1) taking a porous inert material as a carrier, and performing pre-impregnation treatment on the carrier by adopting an organic acid solution; and (2) preparing an impregnating solution with a water-soluble compound containing transition metal elements and a water-soluble compound containing auxiliary elements, impregnating the carrier after treatment in the step (1) with the impregnating solution, drying in shade for 12-48 hours in air at appropriate humidity, then drying and roasting to obtain a final catalyst. When the catalyst prepared by the method disclosed by the invention is used for high-concentration organic wastewater, the characteristics of high activity, good stability and the like are realized, and the energy consumption and the investment can be reduced.

The invention features methods and systems for producing commercial quality carbon dioxide (CO2) of 90% to +99% purity using, wet, fine particle limestone produced in a manufacturing operation, for instance, a limestone quarry as a feedstock to a multi-stage limestone calcination process. This process may be fueled with negative cost waste water treatment plant (WWTP) sludge, biomass, coal, or other low cost solid fuels. High reactivity lime product required in the an adjacent paper mill's PCC manufacturing plant is also produced, and steam and heated boiler feed-water is generated and exported to the mill's steam distribution and generation system as well as hot process water for use in the mill's manufacturing operation. The system for calcining fine particle limestone produced in a quarry manufacturing operation and converting it to lime and CO2 comprises a calciner and a combustor linked by a moving media heat transfer (MMHT) system or apparatus. The MMHT system or apparatus thermally links separate fluid bed combustion (exothermic) and calcination (endothermic) stages with a solid particulate media. The fluid bed calcination stage is fluidized with steam. The system further comprises a dryer / pre-heater that utilizes exhausted heat from the calcination stage.

The invention relates to a method for carrying out oxidation treatment on organic waste water by utilizing a three-dimensional electrode electro-fenton and a device thereof. The device comprises a reactor shell, a carbon material cathode, an iron plate anode, a three-dimensional particle electrode of a fixed bed, a direct-current voltage-stabilizing power supply, a microporous aeration plate and an air pump, wherein a reactor consists of a reaction chamber and a gas chamber; the carbon material cathode, the iron plate anode and the particle electrode are positioned in the reaction chamber at the upper part of the reactor; and the gas chamber is formed between the bottom of the reactor and the microporous aeration plate. After direct current is introduced, the iron anode is oxidized to generate iron ions, oxygen in the gas chamber is reduced on the surface of the cathode to generate hydrogen peroxide, and the iron ions and the hydrogen peroxide form a fenton reagent to oxidize and remove organic matters in waste water; and simultaneously, due to the particle electrode, the contact area and the contact time of the waste water and the fenton reagent are increased, and the mass transfer effect of the waste water in the reactor is reduced. The invention is applicable to treatment of various types of organic waste water, the equipment is compact, the operation is easy, the whole reactor is easy to control, and the requirements of an actual water treatment unit are met.

The invention provides a zero-discharge treatment method of salt-containing organic wastewater. The method comprises the following steps that biochemical treatment and filtering treatment are performed on wastewater; then, membrane concentration is performed; pure-water-producing high-organic-matter-content membrane concentration concentrated water and optional low-organic-matter-content membrane concentration concentrated water are obtained; the high-organic-matter-content membrane concentration concentrated water is used for high-grade oxidation treatment; high-grade oxidation produced water is used for regulation treatment to obtain high-grade oxidation outlet water; the obtained high-grade oxidation outlet water is subjected to evaporation treatment; or the obtained high-grade oxidation outlet water and the low-organic-matter-content membrane concentration concentrated water are mixed under the condition that the low-organic-matter-content membrane concentration concentrated water exists in the step, and then, the evaporation treatment is carried out; external discharge concentration liquid of an evaporator and / or high-salt-content high-organic-matter-content wastewater discharged during the tank brushing of the evaporator are conveyed back into a high-grade oxidation treatment unit; after the liquid is mixed with the high-organic-matter-content membrane concentration concentrated water, the high-grade oxidation treatment is carried out. The wastewater treatment method is stable and reliable; the long-period and stable operation of an evaporation system can be ensured; the zero discharge of the industrial wastewater is realized.

The invention relates to an ultrasonic combined waste water treatment process of refuse leachate, relating to the technical field of waste water treatment and recycling of resources and environmental protection. The ultrasonic combined waste water treatment process of the refuse leachate comprises the following steps of: enabling waste water to enter a regulating pond; treating colloids, amphoteric substances and heavy metals in a coagulation sedimentation pond; eliminating ammonia nitrogen in an ultrasonic catalytic oxidation pond; sequentially sedimentating through biological treatment in an ABR (Acrylate Butadience Rubber) baffle plate anaerobic pond, a hydrolytic pond, a facultative pond and an aerobic pond; filtering in a CMBR (Chatter Membrane Bioreactor); eliminating waste gases and stench in a carbon filter pond; disinfecting in a contact disinfection pond; and filtering in an RO (Reverse Osmosis) membrane reverse osmosis system so as to obtain water meeting the requirements for emission standards. The invention also provides a treatment system for the ultrasonic combined waste water treatment process. The ultrasonic combined waste water treatment process and system can obtain the outflow water with stable quality by treating the refuse leachate; the treatment system has the advantages of small size and occupying area, high efficiency, low energy consumption and easy realization for mechanical-electrical integration control and management; and in addition, the invention is beneficial to the protection of the original landscapes of a construction party by adopting a non-buried type structure and also reduces the influence of the operation of the treatment system on an office area.

The invention discloses a microbial agent for treating ammonia-containing waste water and a preparation method thereof. The microbial agent for treating ammonia-containing waste water mainly comprises three bacterial strains of nitrobacter sp, nitrosobacteria nitrosomonas sp., denitrobacter sp., and the contents of the three bacterial strains can be regulated or proportioned according to specificcultivation conditions and product requirements through methods of oriented domestication, and the like. The cultivation method comprises the following steps of: enriching a bacterial source, purifying and amplifying stage by stage for cultivating. The microbial agent can be used for oriented domestication according to a waste water treatment result so as to improve the content of a target bacterial strain. The cultivation method has the advantages of high cultivation efficiency, large production capacity, and the like and is suitable for commercially producing complex microorganisms for treating the ammonia-containing waste water in a large scale. The obtained microbial agent can effectively treat low-COD (Chemical Oxygen Demand) and high-ammonia-nitrogen waste water, such as waste water of catalyst production, and the like.

A self-sustaining wastewater treatment facility abates greenhouse gas abatement, captures CO2 and produces biomass to address multiple critical environmental needs. The facility includes an array of rotating media wheels that create an optimum ordered mixing of algae for sustained growth. Biomass harvested from the rotating media wheels may be provided to other processing facilities to produce, for instance, bio-fuels. Waste CO2 from the processing facility may also be returned to the treatment system for enhanced algae growth. Bacteria are provided to form a symbiotic relationship with the algae, fueled by sunlight to effectively remove toxic materials from the wastewater. The multi-functional facility may also be integrated into a regenerative facility in which the biomass obtained from the algal and bacterial colonies is used in a separate facility and byproducts of the operation of the separate facility are used by the multi-functional facility to fuel further algal growth.

The invention relates to an aerobic wastewater digestion unit useful for degrading organic material dissolved or suspended in a wastewater stream. The wastewater is fed to a vessel, wherein it is circulated by a liquid conveyor between the vessel and a downwardly-directed tube. Expulsion of fluid from the tube into the lower portion of the vessel agitates the liquid in the vessel and disperses into the liquid air that has been entrained in the liquid in the tube. The digester can be operated using varying liquid levels, and is amenable to batch, semi-batch, and continuous operation. The digester is suitable for use in combination with other components of wastewater treatment systems, and can be included as a module in modular wastewater treatment systems.

The invention relates to a high-capacity intermittent industrial wastewater microwave photocatalytic degradation device, belonging to the technical field of wastewater treatment. The existing microwave photocatalytic degradation technology for the organic pollutant-containing industrial wastewater has the problems that microwave energy is wasted and practical single-jar wastewater treatment quantity is relatively small, and has the problem of scaling since an electrodeless ultraviolet lamp screen protector in the device is soaked in wastewater liquid by the outer side face of a quartz tube for a long term. The invention intends to solve the problems globally.In order to solve the problems, an electrodeless ultraviolet lamp is arranged in a silk screen cage-shaped nonopaque microwave restraining device made from metal material, the microwave is guided into the microwave restraining device to be restrained, the useless dissipation of the microwave can be stopped, and the designed volume of an expander can be allowed to be greatly enlarged on the basis of the structure, so that the single-jar wastewater treatment quantity of a reactor can be greatly improved. An ultrasonic transducer is attached to the outer side face of the side wall of the reactor, so that the scale can be timely removed after the high-frequency ultrasonic wave reaches up to the scale.

A compact portable modular wastewater treatment system which integrates several processing technologies to provide a substantially purified water source. A wastewater stream is sent through an initial filtration step. The filtered wastewater is then subjected to electrocoagulation and then further filtered. The resulting stream containing substantially only organics is then treated in an advanced oxidation process which can include passing an electrical current through the water during the oxidation process. The partially treated water is then passed through ion-exchange columns to polish ammonium and other contaminants. The ion-exchange columns are cycled through regeneration cycles to provide continuous ion-exchange medium. The ammonium rich brine solution used in regeneration is subjected to an ammonium destruct process and then reused in regenerating ion-exchange columns. The water can then be sent through a final disinfection oxidation process to destroy or inactivate pathogens and / or remove any remaining colorants or odor to provide a water source suitable for almost any use.

The invention discloses a salt-tolerant microbial agent and a preparation method thereof. The microbial agent contains staphylococcus cohnii FSND-C, arthrobacter creatinolyticus FDN-1, flavobacterium mizutaii FDN-2, paracoccus denitrificans DN-3 and methylobacterium phyllosphaerae SDN-3. The microbial agent can achieve removal of ammonia nitrogen, total nitrogen and CODcr in the same reactor, has a good wastewater treatment effect, and can achieve short-cut nitrification and denitrification or simultaneous nitrification and denitrification while removing COD. Staphylococcus cohnii FSND-C can utilize various carbon sources, has certain salt tolerance, can be applied to the high-salinity wastewater treatment process, simultaneously can secrete a substance under environmental stimulus to enhance the flocculability of sludge, and further widens the application range of the microbial agent.

A wastewater treatment system and process includes a treatment system for biologically treating wastewater to produce substantially clean water effluent and byproducts. The treatment system includes an array of rotating media wheels for sustained algae growth. The media wheels are supported so that the algae rotates into and out of the wastewater for exposure to sunlight. One byproduct is algae removed from the rotating media wheels, which may be provided to other processing facilities to produce, for instance, bio-diesel fuel. Waste CO2 may also be provided to the facility for enhanced algae growth. Bacteria is provided to form a symbiotic relationship with the algae, fueled by sunlight to effectively remove toxic materials from the wastewater. Rotation of the media wheels can be accomplished by air jets that also operate to dislodge excess algae as a byproduct of the system and process.

The invention relates to a green flocculant- ammonium type cation starch flocculant with high replace degree. Said flocculant employs one of corn starch, wheat starch, tapioca starch, potato starch or any of mixture of them as raw material, takes 3-Chloro-2-hydroxypropyl-trimethylammonium Chloride, or epoxypropyl trimethyl ammonium chloride as cationic etherifying agent, and employs dry method to synthesize said flocculant by using sodium hydroxide and co-catalyst as complex catalyst system. The invention combines the advantage of dry method and semi-dry method, overcomes problem of agglomeration of starch during solution ejection, and solves problems of pasting and agglomeration of starch during reaction process when together with base. The invention is characterized by non post treatment, non three waste, simple processes, short reaction period, mild reaction condition, high efficiency and low cost. The flocculant is characterized when compared with normal ones by less consumption, fast settling speed, high transparency, and wide use for wastewater treatment and sludge waterless in industries such as paper making, dyeing, leathering making and petrochemical industry.

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.