A system and method for wastewater treatment and nutrient removal

Abstract

The present invention relates to a system (1000) for use in treatment of a wastewater stream and nutrient removal by continuous-flow operation in accordance with a general flow direction (F) from a wastewater influent (500) towards a treated water effluent (501). The system (1000) comprises a base (10) configured to, when in use, support the wastewater stream against gravity (g); and further comprises a first section (1) and a second section (2) that are consecutively arranged along the flow direction (F). The first section (1) is configured for anaerobic operation by, when in use, blocking air entrance; and comprises one or more introduction sections (101) suitable for use as a biophosphorus phase, followed by one or more continuation sections (102), and a roof (11) positioned distal to the base (10) opposite to gravitational (g) direction; whereas the second section (2) is integrated to and in fluid flow communication with the first section (1), and comprises one or more denitrification sections (201) configured for subjecting the wastewater arriving from the first section (1) to denitrification, and one or more aeration sections (202) configured for aeration of the wastewater. The present invention further proposes a method that is suitable for employing such system, and that provides wastewater treatment along with nutrient removal.

Description

[0001] A SYSTEM AND METHOD FOR WASTEWATER TREATMENT AND NUTRIENT REMOVAL

[0002] Technical field of the Invention

[0003] The present invention relates to wastewater treatment technology. In particular, the present invention relates to anaerobic treatment and nutrient removal in a reactor.

[0004] Background of the Invention

[0005] Anaerobic reactors are employed in commercial treatment of wastewaters with high organic content, yet, such wastewaters can also include a high extent of nutrient content. In order to fulfill the requirements of discharge standards, it is important to employ biological nutrient removal processes after the anaerobic reactors in treatment of this type of wastewaters.

[0006] To this end, it is desired to develop systems with low investment and operating costs.

[0007] Brief Description of the Invention

[0008] Primary object of the present invention is to overcome the shortcomings in the prior art. Another object of the present invention is provision of a system that enables wastewater treatment and biogas production simultaneous with nutrients removal with low investment and operating costs, along with a method within the same context. These objects are achieved with the system and method that are described in the present specification and within the scope of the appended independent claims.

[0009] The present invention relates to a bioreactor system in which a wastewater treatment apparatus with an anaerobic baffle is combined with a biological nutrient removal apparatus, and a method within the same context. The developed novel system and method enable biogas and energy generation by anaerobic treatment of wastewater, in combination with biological nutrients removal.

[0010] The bioreactor system (abbreviated as: system) that is proposed within the context of the present invention, is configured for use in wastewater treatment and nutrient removal by continuous operation along a flow direction from a wastewater influentinfluent towards a treated water effluent. Said system includes a base that is configured for, in use, supporting the wastewater stream against gravity. The system further includes the following features, that are consecutively configured along the flow direction: a first section that includes one or more introduction sections that are suitable for use as biophosphorus phase, followed by one or more continuation sections, a roof that is positioned distal with respect to the base in a direction opposite to the gravity; the first section being configured for anaerobic operation by, when in use, blocking atmospheric air from entering thereinto; and a second section that is integrated to and in fluid flow communication with the first section; comprising one or more denitrification sections and one or more aeration sections, that are respectively configured for denitrification and aeration of wastewater flowing from the first section.

[0011] A preferred embodiment of the system according to the present invention comprises one or more overflow baffles that, when in use, extend from the base towards the roof along a height in the gravitational orientation.

[0012] Said embodiment preferably includes one or more separators (in other terms, separation baffles) that are positioned at a distal end of the roof with respect to the wastewater influent regarding the general flow direction. Preferably, a closest distance of the separator orthogonal to the base has a value that is smaller than said height. This feature provides that the separator extends from the roof in the gravitational direction to a level that is below the liquid level; thereby, when the system is in use, air contact is blocked between the first section and second section, air passage into the first section (in a direction that is opposite to the general flow direction) is prevented, thus providing the anaerobic operation of the first section.

[0013] In a preferred embodiment, the system according to the present invention further comprises one or more first transfer lines configured for conduction of liquid content (here: mixed liquor suspended solids, abbreviated as MLSS; that is a liquor that contains sludge and / or suspended biomass) from the denitrification section to the introduction section. In a preferred embodiment, the system according to the present invention further comprises one or more second transfer lines configured for conduction of liquid content (here: wastewater, biomass and / or MLSS) from the introduction section to the aeration section. The system according to the present invention enables a successful provision of an efficient nutrient removal during the treatment of wastewaters with a high extent of chemical oxygen demand.

[0014] A preferred embodiment of the system according to the present invention comprises one or more separation units configured for separation of sludge and biomass from the wastewater (that is, a liquid mixture that includes biomass) that passes through the second section. Said embodiment further comprises one or more third transfer lines configured for conduction of liquid content (here: biomass) from the separation unit to the second section. In the case where the aeration section in the second section is configured after the denitrification section in accordance with the general flow direction, preferably, the system comprises one or more fourth transfer lines that are configured for conduction of liquid content (here: wastewater that includes MLSS and / or nitride(s) / nitrate(s)) from the aeration section to the denitrification section.

[0015] A preferred embodiment of the system according to the present invention comprises a biogas outlet that is configured for discharge of biogas from a gas phase that is in the first section.

[0016] A preferred embodiment of the system according to the present invention comprises one or more deflectors that are configured for redirecting wastewater stream that flows in the general flow direction into the gravitational direction. In this embodiment, said one or more deflectors can be configured with a distance from the base, such that wastewater stream is allowed to pass over the base.

[0017] In a preferred embodiment of the system according to the present invention, the continuation section in the first section comprises one or more overflow baffles, that extend from the base towards the roof in the gravitational orientation.

[0018] Further preferably, said embodiment comprises one or more deflectors matching with the one or more overflow baffles, such that, in accordance with the general flow direction, said one or more deflectors are configured successive to respective one or more overflow baffles.

[0019] A preferred embodiment of the system according to the present invention comprises one or more sludge outlet ports configured for discharge of sludge from the first section and / or second section.

[0020] A preferred embodiment of the system according to the present invention comprises one or more liquid sample ports configured for provision of wastewater sample from the first section and / or second section.

[0021] A preferred embodiment of the system according to the present invention comprises a gas inlet line configured for, when in use, feeding of gas (here: air, or a mixture that includes oxygen) from outside into the wastewater in the aeration section.

[0022] In a possible embodiment of the system according to the present invention, the separation unit is in the form of a sedimentation unit that is configured outside the second section, or in the form of a membrane unit that is considered "external" by being also configured outside the second section.

[0023] In another possible embodiment of the system according to the present invention, the separation unit is in the form of an internal membrane unit that is configured suitable to be operated such that, when in use, the separation unit is dipped inside the second section (that is, inside the MLSS that is in the second section).

[0024] A preferred embodiment of the system according to the present invention is suitably configured for, when in use, separation of sludge from the third transfer line.

[0025] A preferred embodiment of the system according to the present invention comprises one or more means for mixing in the denitrification section.

[0026] In accordance with the context that is disclosed above, the present invention proposes a method for wastewater treatment and nutrient removal using a system with continuous operation in accordance with a general flow direction from a wastewater influent towards a treated water effluent. The method according to the present invention includes the following features: i) transferring of a wastewater that enters into the system, to one or more introduction sections that function as a biophosphorus phase configured for release of phosphorus; ii) transferring of the wastewater that exits from said one or more introduction sections into a continuation section that is formed from one or more stages; iii) protecting of a first section that is formed from said one or more introduction sections and continuation section from access of air thereinto; and iv) transferring of the wastewater that exits from said first section, into a second section that includes a denitrification section that functions as an anoxic phase that is configured for subjecting said wastewater to denitrification, and an aeration section that functions as an oxic phase that is configured for subjecting said wastewater to an aerobic treatment; thereby subjecting the wastewater to denitrification and to anaerobic treatment.

[0027] A preferred implementation of the method according to the present invention includes passing the wastewater over one or more overflow baffles that have a height, for arranging that the wastewater has a pre-determined level along the gravitational orientation whilst proceeding through the first section.

[0028] A preferred implementation of the method according to the present invention includes, at the passage of the wastewater from the first section into the second section, passing the wastewater under one or more separators that extend from a roof of the first section towards a base of the first section, and that are configured for blocking air communication into the first section.

[0029] A preferred implementation of the method according to the present invention can include one or more, preferably all of the following features: v) subjecting the wastewater that passes through the second section to a separation at one or more separation units, thereby division of the wastewater into the following fractions: treated water, waste sludge and biomass (here, the biomass can be considered as a return sludge); vi) transferring of sludge and / or MLSS from the second section into the introduction section; vii) transferring of wastewater, biomass and / or MLSS from the introduction section into the aeration section; viii) transferring of biomass from the separation unit into the second section.

[0030] In an implementation of the method according to the present invention, the aeration can be performed prior to the denitrification. On the other hand, in a preferred implementation, the denitrification in the second section can be performed prior to the aeration; in such case, the method according to the present invention includes transferring of MLSS and / or wastewater that contains nitride(s) / nitrate(s) from the aeration section into the denitrification section. In other words; a preferred implementation of the method according to the present invention includes, in the second section, subjecting of the wastewater to denitrification and then to aeration in accordance with the general flow direction. This implementation further includes transfer of wastewater that contains MLSS and / or nitride(s) / nitrate(s) from the aeration section into the denitrification section.

[0031] A preferred implementation of the method according to the present invention includes discharging of biogas from the first section.

[0032] A preferred implementation of the method according to the present invention includes redirecting of the wastewater stream that flows in the flow direction into the gravitational direction, by means of one or more deflectors, and passing the wastewater stream under said deflectors.

[0033] In a preferred implementation of the method according to the present invention, the wastewater is passed over one or more overflow baffles that have a height, for provision of the wastewater with a level along the gravitational orientation whilst proceeding through the first section.

[0034] In a preferred implementation, upon passing over each of the overflow baffles that are provided in a plurality, the wastewater is redirected in the gravitational direction by means of respective deflectors, and passed below said deflectors.

[0035] A preferred implementation of the method according to the present invention includes discharging of sludge from the first section and / or second section.

[0036] A preferred implementation of the method according to the present invention includes obtaining of liquid sample from the first section and / or second section. A preferred implementation of the method according to the present invention includes feeding of air or an oxygen-containing mixture from outside into the wastewater (here: MLSS) in the aeration section.

[0037] Said feeding of air or oxygen-containing mixture can be performed by means of one or more diffusors and / or one or more mechanical aeration units.

[0038] A preferred implementation of the method includes removal of waste sludge prior to the transfer of biomass (here: return sludge) from the separation unit into the second section.

[0039] Detailed Description of Drawing(s)

[0040] Fig.l is a perspective section view of an exemplary system within the context of the present application.

[0041] Detailed Description of the Invention

[0042] With reference to the Fig.l that is briefly explained above, the present invention relates to a system (1000) for use in wastewater treatment and nutrient removal by continuous operation along a flow direction (F) from a wastewater influent (500) towards a treated water effluent (501). Said system (1000) comprises a base (10) that is adapted for, when in use, supporting the stream of the wastewater against gravity (g). The system (1000) further comprises the following features that are consecutively configured along the flow direction (F): a first section (1) that includes one or more introduction sections (101) that are suitable for use as biophosphorus phase, followed by one or more continuation sections (102), a roof (11) that is positioned distal with respect to the base (10) in a direction opposite to the gravity (g); the first section (1) being configured for anaerobic operation by, when in use, blocking atmospheric air from entering thereinto; and a second section (2) that is integrated to and in fluid flow communication with the first section (1); comprising one or more denitrification sections (201) and one or more aeration sections (202), that are respectively configured for denitrification and aeration of wastewater flowing from the first section (1).

[0043] Regarding the suitability of said one or more introduction sections (101) for use as biophosphorus phase: in the technical field environmental engineering, the criteria for evaluation of a treatment unit or stage as a biophosphorus phase (in other words; parameters, conditions and configurations required for biological phosphorus removal in activated sludge systems) are within the common general knowledge. Within the scope of said general knowledge, in order to utilize as a biophosphorus phase, the introduction section (101) is operated anaerobically, and used with polyphosphate accumulating organisms (abbreviated as: PAOs) (e.g., suitable heterotrophic bacteria). Said organisms can be produced inside MLSS, for instance, by using an inoculation sludge (Lat: inoculum}.

[0044] By means of the set of features of the system (1000) according to the present invention, that are compiled above, an effective nutrient removal can be successfully achieved during the treatment of wastewaters with a high extent of chemical oxygen demand (COD).

[0045] A preferred embodiment of the system according to the present invention can include one or more overflow baffles (110) that, when in use, extend from the base (10) towards the roof (11) along a height (h) in the gravitational (g) orientation. Hence, when the system (1000) is in use, each of the overflow baffles (110) determine the fluid level of the wastewater stream that flows through the first section (1), by provision of the wastewater stream with an overflowing level that corresponds to said height (h); and furthermore, a stage is formed in-between each couple of consecutively configured overflow baffles (110).

[0046] Said embodiment preferably further comprises one or more separators (12) that are positioned at a distal end of the roof (11) with respect to the wastewater influent (500) regarding the general flow direction (F). Preferably, a closest orthogonal distance between the separator (12) and the base (10) has a value that is smaller than said height (h). The system (1000) embodiment as described here sets an example that, when in use, prevents air communication into the first section (1) from surroundings and from the second section (2).

[0047] A preferred embodiment of the system (1000) according to the present invention further comprises one or more separation units (3) configured for separation of the wastewater that passes through the second section (2) from sludge and biomass.

[0048] A preferred embodiment of the system (1000) according to the present invention further comprises one or more first transfer lines (Hl) configured for conduction of liquid content (here: sludge and / or MLSS) from the denitrification section (201) to the introduction section (101). A preferred embodiment of the system (1000) according to the present invention further comprises one or more second transfer lines (H2) configured for conduction of liquid content (here: wastewater, biomass and / or MLSS) from the introduction section (101) to the aeration section (202). A preferred embodiment of the system (1000) according to the present invention further comprises one or more third transfer lines (H3) configured for conduction of liquid content (here: biomass) from the separation unit (3) to the second section (2). In a further possible embodiment of the system according to the present invention, the third transfer line (H3) can be configured for conduction of liquid content from the separation unit (3) to the biophosphorus phase (introduction section, 101). In such case, one or more first transfer lines (Hl) that is configured for conduction of liquid (here: sludge and / or MLSS) may be not necessary. In the case where the aeration section (202) in the second section (2) follows the denitrification section (201) regarding to the general flow direction ( F), preferably, one or more fourth transfer lines (H4) can be provided for conduction of liquid content (here: MLSS and / or wastewater containing nitride(s) / nitrate(s)) from the aeration section (202) to the denitrification section (201).

[0049] A preferred embodiment of the system according to the present invention can comprise one or more biogas outlets (H5) configured for discharge of biogas from a gas phase that is in the first section (1), when in use.

[0050] A preferred embodiment of the system according to the present invention comprises one or more deflectors (111) configured for, when in use, redirecting wastewater stream that flows in the general flow direction (F) into the gravitational (g) direction. In this embodiment, said one or more deflectors (111) can be configured with a distance from the base (10), such that wastewater stream is allowed to pass over the base (10). Thus, after passing each deflector (111), the wastewater sweeps the base (10) and thereby increases the agitation of the sludge that accumulates on the base, thereby enhancing the mixing and uniform distribution.

[0051] In a preferred embodiment of the system according to the present invention, the continuation section (102) in the first section (1) can comprise one or more overflow baffles (110) that extend from the base (10) towards the roof (11) in the gravitational (g) orientation. Thus, a stage is formed in-between each consecutive overflow baffles (110) on the general flow direction (F), thereby the system is provided with a plurality of stages that are arranged as an anaerobic treatment cascade.

[0052] Said embodiment can further preferably comprise deflector(s) (111) that match with the one or more overflow baffles (110) and respectively follow the one or more overflow baffles (110) in the general flow direction (F). So, a stage is formed in-between each consecutive overflow baffle (110) - deflector (111) pairs; thereby each stage, in which the anaerobic treatment takes place, receives wastewater from bottom, the agitation of the sludge that accumulates on the base is increased, thus enhancing the mixing and uniform distribution inside the respective stage(s).

[0053] A preferred embodiment of the system according to the present invention can comprise one or more sludge outlet ports (112), that are suitably configured for discharge of sludge from the first section (1) and / or second section (2). The sludge, amount of which gradually increases in the system (1000) can be discharged via said sludge outlet ports (112); thereby enabling an uninterrupted and predictable operation of the system.

[0054] A preferred embodiment of the system according to the present invention can comprise one or more liquid sample ports (113), that are suitably configured for sampling of wastewater from the first section (1) and / or second section (2). With this embodiment, momentary compositions inside the system (1000) can be tracked, and it can be observed whether the related parameters necessitate any arrangement.

[0055] A preferred embodiment of the system according to the present invention can comprise a gas inlet line (H6) configured for, when in use, feeding of gas (here: air, or a mixture that includes oxygen) from outside into the wastewater in the aeration section (202).

[0056] In a possible embodiment of the system according to the present invention, the separation unit (3) can be in the form of a sedimentation unit or an external membrane unit. The sedimentation unit or membrane unit can be considered as external units by being disposed outside the second section (2).

[0057] In another possible embodiment of the system according to the present invention, the separation unit (3) is in the form of an internal membrane unit that is configured suitable to be operated such that, when in use, the separation unit (3) is dipped into the wastewater that is inside the second section (2). In the case where the separation unit (3) has a membrane structure and it is operated by being dipped inside the aeration section (202), the third transfer line ( H 3) can be configured to provide liquid content transfer from the aeration section (202) into the denitrification section (201); this can particularly be the case for the embodiments in which the denitrification section (201) is followed by the aeration section (202) in accordance with the general flow direction (F).

[0058] A preferred is suitably configured for separation of waste sludge (A3) from the third transfer line (H3), when in use. In an exemplary case where the separation unit (3) is in the form of a sedimentation unit; the system (1000) can comprise a further means for separation that is configured for separation of waste sludge (A3) from a biomass - sludge mixture that deposits to the bottom of the separation unit (3), when in use.

[0059] On the other hand, in the case where the separation unit (3) is in the form of a membrane unit that is internal (that is, dipped into the second section (2)); as a cake layer accumulates on its surfaces when in use, the separation unit (3) can be cleaned upon extracting the same from the second section (2).

[0060] A preferred embodiment of the system according to the present invention can comprise one or more means for mixing (114) in the denitrification section (201).

[0061] In accordance with the context that is disclosed above, the present invention proposes a method for wastewater treatment and nutrient removal using a system (1000) with continuous operation in accordance with a general flow direction (F) from a wastewater influent (500) towards a treated water effluent (501). The method according to the present invention includes the following features: i) transfer of a wastewater stream (Al) that is introduced into the system (1000), to one or more introduction sections (101) that function as a biophosphorus phase that is configured for release of phosphorus; ii) transfer of the wastewater that exits from said one or more introduction sections (101) into a continuation section (102) that is formed from one or more stages; iii) protection of a first section (1) that is constituted from said one or more introduction sections (101) and continuation section (102) from communication with outside air; and iv) transferring of the wastewater that exits from said first section (1), into a second section (2) that comprises a denitrification section (201) that functions as an anoxic phase that is configured for subjecting said wastewater to denitrification, and an aeration section (202) that functions as an oxic phase that is configured for subjecting said wastewater to an aerobic treatment; thereby subjecting the wastewater to denitrification and to anaerobic treatment.

[0062] An efficient nutrient removal can be successfully performed simultaneous with treatment of wastewater with a high extent of chemical oxygen demand (COD), with the merits of the set of method features that are compiled above.

[0063] A preferred implementation of the method according to the present invention can include can include passing the wastewater over one or more overflow baffles (110) that have a height (h), in order to arrange that the wastewater has a pre-determined level along the gravitational (g) orientation whilst proceeding through the first section (1). Thus, by means of each overflow baffle (110), the wastewater stream is provided with an overflow level that corresponds to said height (h) thereby determining the level of the wastewater stream flowing through the first section (1); and furthermore, providing a stage in-between each couple of consecutively arranged overflow baffles (110).

[0064] A preferred implementation of the method according to the present invention can include, whilst the wastewater passes from the first section (1) into the second section (2), passing the wastewater under one or more separators (12) that extend from a roof (11) of the first section (1) towards a base (10) of the first section (1), and that are configured for blocking air communication into the first section (1). Thereby, whilst the implementation of the method, an exemplary application is provided that allows the prevention of air communication into the first section (1) from surroundings and from the second section (2).

[0065] In order to maximize the efficiency in nutrient removal, preferred implementations of the method according to the present invention can include one or more, preferably all of the following features: v) subjecting the wastewater that passes through the second section (2) to a separation at one or more separation units (3), for dividing the wastewater into treated water (A2), waste sludge (A3) and biomass (here, the biomass can be considered / utilized as a return sludge); vi) transferring sludge and / or MLSS from the second section (2) into the introduction section (101); vii) transferring wastewater, biomass and / or MLSS from the introduction section (101) into the aeration section (202); viii) transferring biomass from the separation unit (3) into the second section (2).

[0066] In an implementation of the method according to the present invention, the aeration can be performed prior to the denitrification. In a yet preferred implementation, the denitrification in the second section can be performed prior to the aeration; if this is the case, the method according to the present invention includes transfer of the sludge and / or MLSS from the aeration section into the denitrification section. That is, a preferred implementation of the method according to the present invention can include subjecting the wastewater to denitrification and then aeration in the second section (2) with regard to the general flow direction (F), and refluxing of nitride(s) and nitrate(s) by transferring of content (preferably, MLSS) from the aeration section (202) to the denitrification section (201). Said reflux operation provides removal of nitride(s) / nitrate(s) after the aeration. Said transfer operation can be performed through one or more fourth transfer lines (H4) that is described above.

[0067] A preferred implementation of the method according to the present invention can include discharging of biogas from the first section. Said discharging operation can be performed through one or more biogas outlets (H5).

[0068] A preferred implementation of the method according to the present invention can include redirection of the wastewater stream that flows in the flow direction (F) into the gravitational (g) direction, by means of one or more deflectors (111), and passing the wastewater stream under said deflectors (111). Thus, when passing each of the deflectors (111), the wastewater stream sweeps the sludge that has the tendency to deposit on the base (10) due to the gravity, thereby increasing the agitation, and provides enhanced mixing and uniformity in distribution.

[0069] In a preferred implementation of the method according to the present invention, the wastewater can be passed over a plurality of overflow baffles (110) with a height (h), in order to provide the wastewater with a level in the gravitational (g) orientation as it proceeds through the first section (1). Thus, an anaerobic treatment cascade can be provided by formation of a respective stage in-between each consecutive couple of overflow baffles (110) along the general flow direction (F). In a preferred implementation, after passing each of the overflow baffles (110), the wastewater can be redirected in gravitational (g) direction by means of a respective deflector (111), and passed below said deflectors (111). In such case, a stage is formed in-between of each consecutively arranged overflow baffle (110) - deflector (111) couples; an increased extent of agitation of sludge that accumulates on the bottom zones of each of the sections, is achieved; thereby enhancing the mixing and uniform distribution throughout respective stage(s).

[0070] A preferred implementation of the method according to the present invention can include discharging of sludge from the first section (1) and / or second section (2). Thereby the amount of sludge inside the system can be maintained at a pre-determined extent, thus allowing the extension of time period along which the method is implemented without interruption.

[0071] A preferred implementation of the method according to the present invention can include obtention of wastewater sample from the first section (1) and / or second section (2). By obtaining and analyzing the wastewater sample, it can be anticipated whether the parameters necessitate an adjustment.

[0072] A preferred implementation of the method according to the present invention can include feeding of air or an oxygen-containing mixture from outside into the aeration section (202). Oxygen that is introduced by means of said feeding, is thus brought into contact with the wastewater that undergoes treatment inside the aeration section (202). Regarding its content / category, the wastewater that undergoes treatment inside the aeration section can be considered as MLSS.

[0073] A preferred implementation of the method can include removal of waste sludge prior to transfer of biomass (here, the biomass can be considered as return sludge) from the separation unit (3) into the second section (2).

[0074] Throughout the present specification, the term "in use" with reference to the system (1000) and / or sections thereof refers to operation of the system (1000) and / or sections thereof; and preferably it is intended to make reference to operation in steady state.

[0075] A preferred embodiment of the system (1000) and am preferred implementation of the method according to the present invention can also be presented as follows:

[0076] Anaerobic treatment processes are considered suitable for treatment of wastewaters with high COD concentrations, because they allow biogas and energy to be obtained. Yet, anaerobic processes alone cannot provide nutrient removal. In order to also ensure nutrient removal, a separate nutrient removal is to be implemented following the anaerobic treatment. The present invention proposes a singlepiece apparatus that enables anaerobic treatment along with nutrient removal. The present invention proposes an apparatus comprising a nutrient removal process, that includes an anaerobic baffleed reactor (continuation section, 102) and biophosphorus phase (introduction section, 101), anoxic phase (denitrification section, 201) and oxic phase (aeration section, 202). The present invention provides biogas generation during the anaerobic treatment of the wastewater in a single system (1000) and simultaneously enables removal of biological nutrients (nitrogen and phosphorus). As a result, space requirement is reduced and also operational costs are reduced by eliminating transportation costs that would incur in the case where separate processes were used.

[0077] The system (1000) according to the present invention is a bioreactor in which an anaerobic baffleed reactor for anaerobic treatment, is integrated with phases that effect nutrient removal (biophosphorus phase, that is, introduction section 101; anoxic phase, that is, denitrification section 201; and aerobic phase, that is, aeration section 202). Within the scope of treatment of wastewaters with high extent of organic matter and nutrients content, in the continuation section (102) that can be considered as baffleed anaerobic partitions, the system (1000) provides a high extent of organic matter removal in parallel to biogas and energy generation. Furthermore, by means of nutrient removal phases (biophosphorus phase, that is, introduction section 101; anoxic phase, that is, denitrification section 201; and aerobic phase, that is, aeration section 202), the system (1000) enables the combined removal of nutrients such as nitrogen and phosphorus, which cannot be removed by anaerobic treatment, yet bear importance in view of discharge standards to receiving bodies. Thanks to the combination of all of these treatment methods in a single system (1000), the initial investment costs as well as the operational costs are decreased to a minimal extent. The roof (11) is separated from the second section (2) (e.g., from the anoxic compartment, that is, the denitrification section 201) by means of a separation baffle (separator 12); thereby, the first section (1) that includes anaerobic compartments is prevented from contacting with oxygen. Furthermore, thanks to this measure, nitrogen gas from the anoxic compartment, that is, from the denitrification section (201) that is disposed in the second section (2), and oxygen outlet from the oxic compartment, that is from the aeration section (202), are prevented from harming the zone that is operated anaerobically and that is disposed in the first section (1).

[0078] The system (1000) is equipped with one or more wastewater influent (500) pipes and one or more wastewater outletwastewater outlet pipes (501), and provides biogas and energy generation along with removal of carbon, nitrogen and phosphorus from wastewaters.

[0079] The wastewater stream (Al) that enters the system (1000) is preferably redirected towards the base (10) in gravitational (g) direction by means of a deflector (111) right after the wastewater influent (500); thereby starts moving along a vertical passage gap (4) that is disposed in-between said deflector (111) and a vertical wall of the reactor. Each of the introduction section (101) and continuation section (102) that are disposed in the first section (1), and of denitrification section (201) and aeration section (202) that are disposed in the second section (2), and possible stages thereof can be defined as an "active zone". Substrate-biomass contact is provided in said active zones, and thus, treatment is achieved.

[0080] Preferably, the anoxic zone, that is, the denitrification section (201), and the oxic zone, that is, the aeration section (202) are separated from each other by means of a deflector (111) that functions as a baffle for protection of the general flow direction (F). Upper portions of the anoxic zone and / or of the oxic zone can be left open for releasing the gases that are generated, to the surroundings. Alternatively, the denitrification section (201) and aeration section (202) can be covered with respective lids that are configured to allow discharge of generated gases (nitrogen, oxygen, carbon dioxide, etc.). For instance, said sections can be respectively equipped with denitrification section gas outlets (H7) and one or more aeration section gas outlets (H8).

[0081] Preferably, the system (1000) is provided with reflux of reactor content at three or more points: first transfer line (Hl) that enables reflux of liquid content (here: biomass-water mixture or sludge and / or MLSS) from the denitrification section (201) which is anoxic zone, to the introduction section (101) which is biophosphorus zone second transfer line (H2) that enables reflux of liquid content (here: wastewater-biomass and / or MLSS) from the introduction section (101) which is biophosphorus zone, to the aeration section (202) which is oxic zone, and once for all, a third transfer line (H3) that enables reflux of biomass that is separated at the separation unit (3) which can for instance be a final sedimentation unit, into the second section (2), for instance, to the denitrification section (201) which is an anoxic zone.

[0082] In the case where, in the second section (2) of the system, the aeration section (202) comes after the denitrification section (201) according to the general flow direction (F), one or more of fourth transfer lines (H4) can further be provided, that are suitable for conduction of liquid content (here, MLSS and / or wastewater content with nitride(s) / nitrate(s) content) from the aeration section (202) to the denitrification section (201).

[0083] Sludge discharge is provided from the sludge discharge ports (112) at the active zones, and sampling is enabled at each stage of the process through liquid sample ports (113) which are also provided at active zones. As a solid-liquid separation unit (3), for instance, a conventional sedimentation unit or decantor, or an internal or dipped membrane apparatus can be employed. In a further implementation within the context of the present application, denitrification and aeration can be employed in another combination (such that the configuration proceeds along the general flow direction (F) as denitrification, aeration, denitrification, aeration). In such implementation, MLSS and / or wastewater with nitride(s) / nitrate(s) content can be transferred from an initial aeration to an initial denitrification. In such implementation, the third transfer line (H3) can be configured to provide transfer from the separation unit (3) to the biophosphorus phase (introduction section, 101).

[0084] Reference signs:

[0085] 1 first section

[0086] 10 base

[0087] 11 roof

[0088] 12 separator

[0089] 101 introduction section

[0090] 102 continuation section

[0091] 110 overflow baffle

[0092] 111 deflector

[0093] 112 sludge outlet port

[0094] 113 liquid sample port

[0095] 114 means for mixing

[0096] 2 second section

[0097] 201 denitrification section

[0098] 202 aeration section

[0099] 3 separation unit

[0100] 4 passage gap

[0101] 500 wastewater influent

[0102] 501 treated water effluent

[0103] 1000 system

[0104] Al wastewater stream

[0105] A2 treated water

[0106] A3 waste sludge

[0107] F general flow direction g gravity h height

[0108] Hl first transfer line

[0109] H2 second transfer line H3 third transfer line

[0110] H4 fourth transfer line

[0111] H5 biogas outlet

[0112] H6 gas inlet line H7 denitrification section gas outlet

[0113] H8 aeration section gas outlet

Claims

YJClaims1. A system (1000) for use in treatment of a wastewater stream and nutrient removal by continuous- flow operation in accordance with a general flow direction (F) from a wastewater influent (500) towards a treated water effluent (501); the system (1000) comprising a base (10) configured to, when in use, support the wastewater stream against gravity (g); a first section (1) and a second section (2) that are consecutively arranged along the flow direction (F) the first section (1) is configured for anaerobic operation by, when in use, blocking air entrance; comprising one or more introduction sections (101) suitable for use as a biophosphorus phase, followed by one or more continuation sections (102), and a roof (11) positioned distal to the base (10) opposite to gravitational (g) direction; the second section (2) is integrated to and in fluid flow communication with the first section (1), comprising one or more denitrification sections (201) configured for subjecting the wastewater arriving from the first section (1) to denitrification, and one or more aeration sections (202) configured for aeration of the wastewater.

2. System according to claim 1, comprising one or more overflow baffles (110) extending from the base (10) to the roof (11) along a height (h) in the gravitational (g) orientation.

3. System according to claim 2, comprising one or more separators (12) positioned at a distal end of the roof (11) in the general flow direction (F) relative to the wastewater entrance (500); a closest distance between the base (10) and said one or more separators (12) in a direction orthogonal to the base (10) being smaller than said height (h).

4. System according to any of claims 1 to 3, comprising one or more separation units (3) configured for separation of sludge and biomass from the wastewater passing through the second section (2).

5. System according to any of claims 1 to 3, comprising one or more of the following: one or more first transfer lines (Hl) configured for conduction of liquid content from the denitrification section (201) to the introduction section (101); one or more second transfer lines (H2) configured for conduction of liquid content from the introduction section (101) to the aeration section (202).

6. System according to claim 4, comprising one or more third transfer lines (H3) configured for conduction of liquid content form the separation unit (3) to the second section (2).

7. System according to claim 6, wherein the separation unit (3) is in the form of a membrane unit by being configured to be operated in a state where said membrane unit is dipped into MLSS in the second section (2).

8. System according to any of claims 6 or 7, configured for, when in use, separation of waste sludge (A3) from the third transfer line (H3).

9. System according to any of claims 1 to 8; comprising one or more fourth transfer lines (H4) for conduction of fluid content from the aeration section (202) to the denitrification section (201); provided that, in the second section (2), the aeration section (202) comes after the denitrification section (201) in accordance with the general flow direction (F). lO.System according to any of claims 1 to 9, comprising one or more biogas outlets ( H 5) configured for biogas discharge from a gas phase in the first section (1), when in use. ll.System according to any of claims 1 to 10, comprising one or more deflectors (111) configured for, when in use, redirection of wastewater stream that flows in the general flow direction (F) into the gravitational (g) direction; wherein said one or more deflectors (111) are configured to allow wastewater to flow on the base (10).12.System according to any of claims 1 to 11, wherein the continuation section (102) in the first section (1) is provided with a plurality of overflow baffles (110), that extend from the base (10) towards the roof (11) along a height (h) in the gravitational (g) orientation.13.System according to claim 12, comprising a plurality of deflectors (111) that are respectively coupled to the one or more overflow baffles (110) and configured to follow the respective overflow baffles (110) in the general flow direction (F).14.System according to any of claims 1 to 13, comprising one or more sludge outlet ports (112) configured for sludge discharge from the first section (1) and / or the second section (2).15.System according to any of claims 1 to 14, comprising one or more liquid sample ports (113) configured for sampling of wastewater from the first section (1) and / or the second section (2).16.System according to any of claims 1 to 15, comprising one or more gas inlet lines (H6) configured for, when in use, feeding of gas from outside into the wastewater in the aeration section (202).17.System according to any of claims 1 to 16, wherein the separation unit (3) is in the form of a sedimentation unit or an external membrane unit that is provided outside the second section (2).18.System according to any of claims 1 to 17, comprising one or more means for mixing (114) in the denitrification section (201).

19. A method for wastewater treatment and nutrient removal by operating a system (1000) with continuous flow from a wastewater influent (500) towards a treated water effluent (501) along a general flow direction (F); the method comprisingi) transferring a wastewater stream (Al) that enters the system (1000), to one or more introduction sections (101) that function as a biophosphorus phase that is configured for release of phosphorus; ii) transferring the wastewater that exits said one or more introduction sections (101) into a continuation section (102) that is formed from one or more stages; iii) protection of a first section (1) that includes said one or more introduction sections (101) and said continuation section (102) from communication with outside air; and iv) transferring of the wastewater that exits from said first section (1), into a second section (2) that comprises a denitrification section (201) which functions as an anoxic phase configured for subjecting said wastewater to denitrification, and an aeration section (202) that functions as an oxic phase configured for subjecting said wastewater to an aerobic treatment; thereby subjecting the wastewater to denitrification and to anaerobic treatment.ZO.Method according to claim 19, wherein the method includes passing the wastewater over one or more overflow baffles (110) that have a height (h), in order to arrange that the wastewater has a pre-determined level along the gravitational (g) orientation whilst proceeding through the first section (1).

21. Method according to any of claims 19 or 20, wherein the method includes passing the wastewater under one or more separators (12) that extend from a roof (11) of the first section (1) towards a base (10) of the first section (1), and that are configured for blocking air communication into the first section (1), whilst the wastewater passes from the first section (1) into the second section (2).

22. Method according to any of claims 19 to 21, including one or more of the following: v) subjecting the wastewater that passes through the second section (2) to a separation at one or more separation units (3), for dividing the wastewater into treated water (A2), waste sludge (A3) and biomass; vi) transferring sludge and / or MLSS from the second section (2) into the introduction section (101); vii) transferring wastewater, biomass and / or MLSS from the introduction section (101) into the aeration section (202); viii) transferring biomass from the separation unit (3) into the second section (2).23.Method according to any of claims 19 to 22, including:subjecting the wastewater that passes through the second section (2) to a separation at one or more separation units (3), for dividing the wastewater into treated water ( A2), waste sludge (A3) and biomass; transferring biomass from the separation unit (3) into the second section (2); removal of waste sludge prior to said transfer of biomass. Method according to any of claims 19 to 23, including aeration of wastewater in the second section (2) after the denitrification in regarding the general flow direction (F); further including return of nitride(s) and nitrate(s) by transferring MLSS from the aeration section (202) to the denitrification section (201). Method according to any of claims 19 to 24, including biogas discharge from the first section (1).Method according to any of claims 19 to 25, including redirection of the wastewater that flows in the general flow direction (F) into the gravitational (g) direction by means of one or more deflectors (111), and passing the wastewater below said deflectors (111). Method according to any of claims 19 to 26, including passing the wastewater over a plurality of overflow baffles (110) that have a height (h), in order to arrange that the wastewater has a predetermined level along the gravitational (g) orientation whilst proceeding through the first section (1). Method according to claim 27, including redirection of wastewater in the gravitational (g) direction upon passing each of said plurality of overflow baffles (110), and then passing the wastewater under respective deflectors (111). Method according to any of claims 19 to 28, including discharge of sludge from the first section (1) and / or the second section (2) and / or collecting wastewater sample from the first section (1) and / or the second section (2). Method according to any of claims 19 to 29, wherein the method includes feeding of air or an oxygen-containing mixture into aeration section. Method according to claim 30, wherein said feeding of air or oxygen-containing mixture is performed using one or more diffusors and / or mechanical aeration units.

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