A system and a process to treat a wastewater stream

Abstract

A process for treating a wastewater and a system to perform the process is developed. The process comprises contacting an incoming wastewater stream with at least one microorganism, activating the at least one microorganism, purifying the incoming wastewater, reducing a nitrate pollution of the incoming wastewater, sedimentation of a plurality of activated sludge aggregates, discharging a clarified effluent, and discharging a stabilized odorless activated sludge after at least 25 days wherein due to a design of the system, the process is carried out in a semi-continuous mode and can withstand the chemical, organic, and hydraulic shocks. The process results in production of a high-quality clarified effluent and the odorless sludge as well as removing a suitable and pre-determined amount of nitrogen.

Description

A SYSTEM AND A PROCESS TO TREAT A WASTEWATER STREAMCROSS REFERENCE TO RELATED APPLICATION

[0001] The present invention application claims priority from pending IRAN Patent Application Serial No. 140250140003005039, filed on October 22, 2023, entitled “WASTEWATER TREATMENT BASED ON ADVANCED SEQUENCING BATCH REACTOR”, which is incorporated by reference herein in its entirety.

[0002] The present application is related to a process, especially based on a sequencing batch reactor process, for treating a wastewater and a system to perform the process such that the process biologically treat the wastewater and produce a stabilized sludge aggregate after at least 25 days.BACKGROUND

[0003] Biological wastewater treatment is one of the most important processes for industrial and sanitary wastewater treatment. Various processes are used in this type of treatment. The purpose of the various biological wastewater treatment processes includes: changing a shape of soluble and particulate matter with an ability to biodegrade into a plurality of final acceptable products, trapping a set of suspended and non-settleable colloidal solids within a biological mass and biofilm, changing a chemical composition of or removing nutrients such as nitrogen and phosphorus especially in wastewater entering agricultural centers, as well as removing a plurality of rare compounds and organic substances in the wastewater, and reducing organic compounds.

[0004] The processes used in the biological treatment include the Anaerobic / Anoxic / Oxic (A2 / O) processes, the Moving Bed Biofilm Reactor (MBBR) process, an anaerobic process such as the anaerobic baffled reactor (ABR), and in more advanced cases, a combination thereof. Another biological treatment process that wildly is in use comprises a sequential batch reactor (SBR) process, which was established in 1920; But since 1960, due to the advances in technology and the production of more modern electromechanical parts, such as high-efficiency blowers and more efficient pumps, the SBR process received more attention.

[0005] High adaptability to an incoming wastewater treatment process, production of healthy bacteria, flexibility in setting process parameters, hydraulic balancing compared to other processes to treat an equal amount of incoming wastewater, are among the advantages of this process, which lead to more usage of this process in wastewater treatment. It has become biological in the following years. Although, along with these advantages, the SBR process has serious operational and strategic problems, such as difficult and complex process control, the need to build two complete and parallel reactors, maintenance that is more complicated, excess sludge production, odor generation, as well as higher investment price, which makes this process faces many challenges.

[0006] Therefore, to overcome the above-mentioned problems and improve the SBR process, an advanced and cost-effective process and a system to perform the process have been developed such that a biological wastewater treatment is performed semi-continuously and produces stabilized odorless sludge aggregates.SUMMARY

[0007] This summary is intended to provide an overview of the subject matter of this patent, and is not intended to identify essential elements or key elements of the subject matter, nor is it intended to be used to determine the scope of the claimed implementations. The proper scope of this patent may be ascertained from the claims set forth below in view of the detailed description below and the drawings.

[0008] In one general aspect, the present disclosure is directed to an exemplary process for treating a wastewater. The exemplary process may comprise seven steps comprising contacting an incoming wastewater stream with at least one microorganism in at least three process vessels, activating the at least one microorganism by an air blowing mechanism into the at least three process vessels for at least one time, purifying the incoming wastewater by carrying out a reaction between the activated microorganism and the incoming wastewater, reducing a nitrate pollution of the incoming wastewater by carrying out at least one time an anaerobic process through stopping the air blowing mechanism into the at least three process vessels, sedimentation of a plurality of activated sludge aggregates resulting from activation of the at least one microorganism, discharging a clarified effluent after a sufficient time, and discharging a stabilized odorless activated sludge after at least 25 days. The exemplary process is carried out in a semi- continuous mode.

[0009] The above general aspect may have one or more of the following features. In an exemplary implementation, the exemplary process may further comprise eliminating a plurality of objects by passing the incoming wastewater stream through at least one separating compartment before entering the incoming wastewater into the at least three process vessels. In an exemplary implementation, a higher aeration rate into a first process vessel of the at least three process vessels may be applied compared to a second process vessel and a third process vessel of the at least three process vessels. In some exemplary implementations, an aeration rate into a first process vessel, a second process vessel, and a third rector of the at least three process vessels may be in a same level. In an exemplary implementation, the steps of activating the at least one microorganism, reducing a nitrate pollution of the incoming wastewater, sedimentation of a plurality of activated sludge aggregates as well as discharging a stabilized activated sludge after at least 25 days may be performed in a same time in a first, second, and third process vessels of the at least three process vessels. In this exemplary implementation, the at least three process vessels maybe hydro-dynamically connected to each other. In some exemplary implementations, a level of aeration rate into a first, a second, and a third process vessels of the at least three process vessels may be reduced by or of a primary level of aeration rate, when an incoming wastewater flow rate into the at least three process vessels is reduced. In an exemplary implementation, the sufficient time for discharging the clarified effluent may be at least 12 hours in accordance with a flow rate of the incoming wastewater. In some exemplary implementations, activating the at least one microorganism and reducing a nitrate pollution of the incoming wastewater may be periodically performed in order to further remove nitrate pollution of the incoming wastewater.

[0010] In another general aspect, the present disclosure is directed to an exemplary system to perform a wastewater treatment process. The exemplary system may comprise at least three process vessels that may be chemically different from each other while may hydrodynamically be connected, at least one air blower, and at least one control unit. The at least three process vessels may configure to perform the treating process and the at least one air blower may configure to provide a sufficient amount of oxygen for activating at least one microorganism. Furthermore, a plurality of process parameters may be controlled utilizing the at least one control unit.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The drawing figures depict one or more implementations in accordance with the present teachings, by way of example only, not by way of limitation. In the figures, like reference numerals refer to the same or similar elements.

[0012] illustrates an exemplary flowchart of an implementation of a general representation of a process for treating a wastewater, consistent with one or more exemplary embodiments of the present disclosure.

[0013] illustrates an exemplary isometric view of a system to perform a wastewater treatment process, consistent with one or more exemplary embodiments of the present disclosure.DETAILED DESCRIPTION

[0014] In the following detailed description, numerous specific details are set forth by way of examples in order to provide a thorough understanding of the relevant teachings. However, it should be apparent that the present teachings may be practiced without such details. In other instances, well-known methods, procedures, components, and / or circuitry have been described at a relatively high-level, without detail, in order to avoid unnecessarily obscuring aspects of the present teachings. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined only by the appended claims.

[0015] The following detailed description is presented to enable a person skilled in the art to make and use the methods and devices disclosed in exemplary embodiments of the present disclosure. For purposes of explanation, specific nomenclature is set forth to provide a thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that these specific details are not required to practice the disclosed exemplary embodiments. Descriptions of specific exemplary embodiments are provided only as representative examples. Various modifications to the exemplary implementations will be readily apparent to one skilled in the art, and the general principles defined herein may be applied to other implementations and applications without departing from the scope of the present disclosure. The present disclosure is not intended to be limited to the implementations shown, but is to be accorded the widest possible scope consistent with the principles and features disclosed herein.

[0016] The present disclosure describes an exemplary process for treating a wastewater comprising at least seven main steps such that an exemplary process may carried out in a semi-continuous mode. The first step may comprise contacting an incoming wastewater stream with at least one microorganism in at least three process vessels. The second and third steps may comprise activating the at least one microorganism by an air blowing mechanism into the at least three process vessels for at least one time and purifying the incoming wastewater by carrying out a reaction between the activated microorganism and the incoming wastewater, respectively. In fourth step, a nitrate pollution of the incoming wastewater may be reduced by carrying out at least one time an anaerobic process through stopping the air blowing mechanism into the at least three process vessels. Furthermore, the fifth step may comprise sedimentation of a plurality of activated sludge aggregates resulting from activation of the at least one microorganism. Additionally, the sixth and seventh steps may comprise discharging a clarified effluent after a sufficient time and discharging a stabilized odorless activated sludge after at least 25 days, respectively. Some benefits from utilizing the exemplary process described within the present disclosure may include, but are not limited to, developing an advanced and eco-friendly process for treating a wastewater, produce an effective stabilized sludge, enhance a decomposition of a plurality of sludge aggregate resulted in a reduction of excess sludge production, removing an unpleasant smell of the plurality of sludge aggregate and produce an stabilized odorless sludge, and produce a higher Mixed Liquor Suspended Solids (MLSS).

[0017] Furthermore, the present disclosure describes an exemplary system to perform an exemplary wastewater treatment process comprising at least three main parts. The first part may comprise at least three process vessels such that the at least three process vessels may configure to perform the treating wastewater process. The at least three process vessels may be chemically different from each other while the at least three process vessels may be hydrodynamically connected with each other. The second part may comprise at least one air blower that may configure to provide a sufficient amount of oxygen for activating at least one microorganism and the third part may comprise at least one control unit such that the control unit may configure to control a plurality of process parameters. In an exemplary system. Some benefits from utilizing the exemplary process described within the present disclosure may include, but are not limited to, developing a cheap and easy-to-use system to perform a semi-continuous wastewater treatment process, eliminating a primary balancing vessel and integrating the concept of balancing with the at least three process vessels, and integrating the sedimentation vessel with the at least three process vessels.

[0018] In an exemplary embodiment, an exemplary process disclosed within the present disclosure may result in producing a treated wastewater. In an exemplary embodiment, the terms “treating”, “treatment”, “treated” or the like may refer to a biological process in which a plurality of aerobic and / or anaerobic microorganisms decompose and remove a plurality of organic substances by feeding on the plurality of organic substances.

[0019] In an exemplary embodiment, an exemplary process disclosed within the present disclosure may result in a stabilized odorless sludge. The term “stabilized odorless sludge” may refer to a semi-solid material that does not undergo a putrefaction after an aeration process is stopped, so leads to prevent spreading any unpleasant odors.

[0020] In an exemplary embodiment, the term “process vessel” or “process vessels” may refer to a container or containers for conducting a reaction between a wastewater and a plurality of microorganisms, which a container / containers volume may be changed in accordance with an incoming wastewater volume as well as an incoming wastewater flow-rate. In an exemplary embodiment, the term “a plurality of microorganisms” may refer to a mass of microscopic organisms that can decompose and eliminate a mass of organic materials through an aerobic process and / or an anaerobic process.

[0021] In an exemplary embodiment, aspects and features of an exemplary process for treating a wastewater and a system to perform thereof in greater detail described, below.A PROCESS FOR TREATING A WASTEWATER STREAM

[0022] The sequential batch reactor process is one of typical wastewater treatment processes that has received a lot of attention over these years. Although, the disadvantages of the SBR process such as difficult and complex process control, complex maintenance, a need to build two complete and parallel process vessels, high production of excess sludge that can result in spreading an unpleasant odor in the environment, etc., can affect the use and efficiency of the SBR process. Therefore, developing an advanced and cost-effective wastewater treatment process is required.

[0023] In an exemplary embodiment, to treat a wastewater stream, specially based on biological reactions, a process has been developed to overcome above-mentioned disadvantages of the SBR process.

[0024] illustrates an exemplary flowchart of an implementation of a general representation of a process100for treating a wastewater, consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, as illustrates in, the process 100 may comprise seven main steps. In step 1 (102), an incoming wastewater stream may contact with at least one microorganism within at least three process vessels. Step104may comprise activating the at least one microorganism by an air blowing mechanism into the at least three process vessels for at least one time. Then, in steps106and108, the incoming wastewater may be purified by carrying out a reaction between the activated microorganism and the incoming wastewater and a nitrate pollution of the incoming wastewater may be reduced by carrying out at least one time an anaerobic process through stopping the air blowing mechanism into the at least three process vessels, respectively. Following that, step110may comprise sedimentation of a plurality of activated sludge aggregates resulting from activation of the at least one microorganism. In step112, a clarified effluent may discharge after a sufficient time and in the final step (114), a stabilized odorless activated sludge may discharge after at least 25 days. In an exemplary embodiment, the process100may carried out in a semi-continuous mod.

[0025] In some embodiments, the process100may further comprise another step. In this step, before entering the incoming wastewater into the at least three process vessels, the incoming wastewater stream may pass through at least one separating compartment that may configure to eliminate a plurality of objects. By entering the incoming wastewater stream into the at least one separating compartment, the incoming wastewater stream may be passed through a plurality of grids that may be mounted within the separating compartment and result in collecting the plurality of objects, for example, but are not limited to, a plurality of large and untreatable components. In one or more exemplary embodiments, a mesh and a size of the plurality of grids may be selected in accordance with a type of the incoming wastewater stream, so the eliminating and separating of the plurality of objects may be done with a highest efficiency. In one or more exemplary embodiments, an arrangement of the plurality of grids may be considered in such a way that a separated mass of objects within the separating compartment do not cause blocking the wastewater stream path, and also after a long period of time, for discharging the separated mass of the objects, there may be no need for stopping the process100.

[0026] In some exemplary embodiments, the separating compartment may comprise at least two channels such that the incoming wastewater stream can pass through the at least two channels lead to the large and untreatable components may be eliminated under normal conditions utilizing at least one grid that may be mounted within each channel of the at least two channels. In one or more exemplary embodiments, the at least two channels may be mounted in a parallel position to each other according to a horizontal axis of the separating compartment. So, during a service period or when it’s necessary to empty the separated mass of the large and untreatable components, the entry of the incoming wastewater stream into a first channel of the at least two channels may be interrupted and the wastewater stream may pass through a second channel of the at least two channels, thus an discharging of the separated mass may be easily done without a need to stop the process100.

[0027] In a common sequencing batch reactor (SBR) process, a residence time of the activated sludge is very short, and before the activated sludge reaches the stabilization stage, the activated sludge is removed from the process vessels and following that is transferred to a sludge storage compartment, thus leads to spread a very unpleasant smell due to exposure of the activated sludge to the anaerobic processes. In one or more exemplary embodiments, in contrast to the common SBR process, the produced activated sludge during the process100may be resided for at least 25 days within the at least three process vessels, so the activated sludge may be stabilized during this period which is also called a “mature sludge”. The residence time of at least 25 days causes the produced stabilized sludge to be odorless even after stopping the aeration process and discharging from the at least three process vessels. In one or more exemplary embodiments, the stabilized odorless sludge may be decomposed to a plurality of safe materials that can be used as a fertilizer in the agricultural industry.

[0028] In one or more exemplary embodiments, the activated sludge can treat the wastewater stream based on different processes, for example, but are not limited to, an attached growth process, a suspended growth process, a combination thereof, and / or other processes that are well-known by those skilled in the art. In some exemplary embodiments, the activated sludge may treat the incoming wastewater stream based on the suspended growth process. In this case, the microorganisms decompose a plurality of organic materials of the wastewater stream due to performing the aerobic process and produce a plurality of biomasses free of harmful substances. The produced biomasses are connected together in a form of granular clusters and settled in a bottom of the at least three process vessels.

[0029] In an exemplary embodiment, the at least three process vessels may be hydrodynamically connected to each other and steps104,108,110, and114of the process100for treating the wastewater stream may be performed in each of at least three process vessels in a same time.

[0030] In an exemplary embodiment, a same level of an aeration rate for activation the microorganism may be blown into each process vessel of the at least three vessels.

[0031] In another exemplary embodiment, a higher aeration rate into a first process vessel of the at least three process vessels may be applied compared to a second process vessel and a third process vessel of the at least three process vessels due to a different chemical composition of the wastewater stream in each vessel of the at least three process vessels.

[0032] In MBBR or A2O processes, a level of aeration rate is fixed and there is no feedback from the wastewater treatment plant conditions. Therefore, when an incoming wastewater stream is reduced, a level of aeration rate is higher than a level of the existing pollution in a process vessel, which means the presence of a very large amount of oxygen in the wastewater stream that is placed inside the process vessel that can lead to two unpleasant phenomena. In a first phenomenon, an equilibrium reaction of the converting ammonium to nitrite and converting nitrite to nitrate proceed one-way towards the production of nitrate, and due to the acidic nature of nitrate, the pH of the wastewater inside the process vessel significantly decreases resulting in an acidification phenomenon of the wastewater that causes the death of the microorganisms and a destruction of the activated sludge. In a second phenomenon, a high concentration of oxygen causes a phenomenon called endogenous respiration in microorganisms that this phenomenon also causes the destruction of the activated sludge. Both of these phenomena will cause a severe decrease in a quality of the effluent, a stench release as well as a production of the excess sludge.

[0033] In an exemplary embodiment, when an incoming wastewater flow rate into the at least three process vessels is reduced, a level of aeration rate into each process vessel of the at least three process vessels may be automatically reduced by or of a primary level of aeration rate. The reduction of the aeration rate level result in preventing the wastewater stream acidification phenomenon as well as the endogenous respiration in microorganisms.

[0034] In one or more exemplary embodiment the sufficient time for discharging the clarified effluent may depend of an incoming wastewater flow-rate. In one or more exemplary embodiment, the sufficient time may be in range of 12 hours to 4 weeks. In an exemplary embodiment, clarified effluent may be discharge after 12 hours.

[0035] In an exemplary embodiment, to further remove of the nitrate pollution from the incoming wastewater, the steps104and108of the process100may be periodically performed.

[0036] In an exemplary embodiment, the process100may be carried out in a semi-continuous mode due to perform the process100in a wastewater treatment system. In an exemplary embodiment, the aspects and features of an exemplary system to perform the process100in greater detail described, below.A SYSTEM TO TREAT A WASTEWATER STREAM

[0037] illustrates an exemplary isometric view of a system200to perform a wastewater treatment process, consistent with one or more exemplary embodiments of the present disclosure. In an exemplary embodiment, the system200may be configured to perform the exemplary process100that is disclosed in the present disclosure. In an exemplary embodiment, as illustrated in, the system200may comprise three main parts. A first part may comprise at least three process vessels that may configure to perform the treating wastewater process100.The at least three process vessels may comprise a first process vessel206, a second process vessel208, and a third process vessel210that the first, second, and third process vessels206,208,210may be hydrodynamically connected to each other while a chemical composition of the first, second, and third process vessels206,208,210are different. A second part may comprise at least one air blower202that may configure to provide a sufficient amount of oxygen for activating at least one microorganism and a second part may comprise at least one control unit212that may configure to control a plurality of process parameters.

[0038] In an exemplary embodiment, the system200may further comprise at least one separating compartment204that may configure to eliminate and remove a plurality of objects, for example, but are not limited to, a plurality of large and untreatable components from the wastewater stream. In an exemplary embodiment, at least one grid2042may be mounted within the separating compartment204to create at least an obstacle for eliminating the plurality of objects. In one or more exemplary embodiments, a type and a mesh size of the at least one grid may be chosen based on a type of the incoming wastewater steam as well as a type and size of the plurality of objects that cause a higher efficiency of elimination of the objects.

[0039] In one or more exemplary embodiments, the separating compartment204may be comprise a plurality of grids to eliminate and remove the objects. In this case, the plurality of grids may be arranged in a specific mode such that a separated mass of objects do not blocking the wastewater stream path. Also, it can cause no need for stopping the system200as well as the process100after a long operation time. In an exemplary embodiment, the specific mode may comprise mounting the plurality of grids in a height above of a surface floor of the separating compartment204such that the height may be at least 15 cm. It is experimentally and operationally proved that almost 99 percent of the plurality of objects are captured and removed by the specific mode arrangement of the grids without interrupting the regime of the incoming wastewater stream.

[0040] In an exemplary embodiment, the system200may further comprise at least one wastewater inlet202, at least one outlet (not shown) that may configure to discharge the stabilized odorless activated sludge, and at least one conduit (not shown) that may configure to discharge a treated effluent.

[0041] In an exemplary embodiment, the at least one outlet (not shown) to discharge the stabilized odorless activated sludge may be mounted within and / or outside the third process vessel210. A stabilized odorless activated sludge content is measured utilizing the Sludge Volume Index (SVI) test after at least 25 days to three months, and if there is a need to discharge the stabilized odorless activated sludge based on the result of SVI, the discharge of the stabilized odorless activated sludge may be done utilizing the at least one outlet (not shown).

[0042] In another exemplary embodiment, each of the first, second, and third process vessels206,208,210may comprise at least one outlet that may configure to discharge the stabilized odorless activated sludge from the first process vessel206, the second process vessel208, and the third process vessel210such that each outlet may be positioned in within and / or outside of each of the first, second, and third process vessels206,208,210. The discharge of the stabilized odorless activated sludge may be done based on the result of SVI test from each process vessel after 25 days or more.

[0043] In an exemplary embodiment, the system200may further comprise a storage compartment214that may configure to maintain the discharged clarified effluent. In an exemplary embodiment, the storage compartment may be positioned next to the third process vessel210.

[0044] In one or more exemplary embodiments, the separating compartment204may comprise at least two channels (not shown) that the at least two channels may be configured to eliminate and remove the plurality of objects under a normal condition such that at least one or a plurality of grids may be positioned within each channel of the at least two channels.

[0045] In some embodiments, the at least two channels (not shown) may be mounted in a parallel position to each other according to a horizontal axis of the separating compartment204. During a service period or when it’s necessary to empty the separated mass of the plurality of the objects, this arrangement of the at least two channels help to operate the process100utilizing the system200without a need to stop the process100. In this case, the incoming wastewater stream into a first channel of the at least two channels may be interrupted, so the incoming wastewater stream may pass through a second channel of the at least two channels and the separated mass can be discharged from the first channel or vice versa.

[0046] In one or more exemplary embodiments, a passage of the incoming wastewater stream through the at least three process vessels206,208,210utilizing the wastewater treatment system200may be contemplated to operate the process100in a semi-continuous mode. In these exemplary embodiments, the first process vessel206may be separated from the second process vessel208utilizing a first barrier205and the second process vessel may be separated from the third process vessel210utilizing a second barrier207. In one or more embodiments, a first aperture and a second aperture with a predetermined dimensions may be embedded within the first barrier and the second barrier, respectively. The first process vessel206may be connected to the second process vessel208and the second process vessel208may be connected to the third process vessel210utilizing the first and second apertures, respectively. Therefore, by using such an arrangement and design, the first to third process vessels206,208,210may be hydrodynamically connected to each other. The wastewater stream may directly enter the first process vessel206after passing the incoming wastewater through the separated compartment204. In these exemplary embodiments, when the incoming wastewater stream enters the first process vessel206, a wastewater level will rise in the first, second, and third process vessels206,208,210in accordance with each other. Although, a chemical connection of the process vessels206,208,210may be disconnected and a plurality of chemical parameters of the first to third process vessels206,208,210may be very different from each other. Additionally, the third process vessel210may be completely closed and it’s not possible to extract the clarified effluent by gravity. Therefore, the disclosed process100may be operated in the semi-continuous mode utilizing the disclosed system200. In other words, the incoming wastewater can enter the first to the third process vessels (206, 208, 210) at any time, while the wastewater stream cannot leave the process vessels206,208,210until a cycle of biochemical and biological reaction between the microorganisms and the wastewater stream is completed.

[0047] In an exemplary embodiment, a height of the first aperture from a bottom surface of the first barrier as well as a height of the second aperture from a bottom surface of the second barrier may be considered such that a minimum level of the incoming wastewater may be in a higher level of both of the first and the second apertures.

[0048] In one or more embodiments, the first aperture height from the bottom surface of the first barrier may be in a range of 0.2 to 0.4 of a total height of the first process vessel206and / or the second process vessel208, and the second aperture height from the bottom surface of the first barrier may be in a range of 0.2 to 0.4 of a total height of the second process vessel208and / or third process vessel210. In one or more embodiments, a first aperture length and a second aperture length may be in a range of 0.08 to 0.14 of a first barrier length and a second barrier length, respectively.

[0049] In one or more exemplary embodiments, a time period of completing the biochemical and biological reaction cycle may depend on a flow-rate of the incoming wastewater stream into the first, second, and third process vessels206,208,210. The time period can be dynamically changed without disturbing a chemical balance of the process vessels206,208,210corresponding to the incoming wastewater stream flow rate changes. Due to this dependence of the time period of completing the biochemical and biological reaction cycle on the incoming wastewater stream flow-rate, the disclosed process100can be operated dynamically and intelligently with respect to the chemical, organic, and hydraulic shocks.

[0050] In an exemplary embodiment, the system200may further comprise a second conduit (not shown) that may configure to return a portion of the activated sludge mass from the third process vessel210to the first process vessel206in order to provide a suitable concentration of the activated microorganism in the first process vessel206.

[0051] In an exemplary embodiment, the biological and biochemical reaction between the incoming wastewater stream and the activated microorganism may configure to take place in a first volume of each of the first process vessel206, the second process vessel208, and third process vessel210.

[0052] In an exemplary embodiment, unlike the MBBR or A2O processes, sedimentation may take place within a second volume of the first, second, and third process vessels206,208,210which eliminates the need for at least one sedimentation compartments in the system200. In other words, in the disclosed wastewater treatment system200, at least one sedimentation compartment may be integrated into each of the at least three process vessels206,208,210. Therefore, a fixed sedimentation time through the process100may be set utilizing the control unit212so a high and low load phenomena will not have any effect on the sedimentation time as well as a wastewater treatment time result in the process100will be independently and constantly done and a high-quality clarified effluent will be achieved. Meanwhile, in the MBBR or A2O processes, a plurality of sedimentation compartments are separately designed next to the process vessels and a treated effluent is entered into the plurality of sedimentation compartments along with the activated sludge. Then, the activated sludge is separated from the treated wastewater by various mechanical and physical process, for example, but are not limited to, the separating processes utilizing decanters, lamella plates, centrifuges, etc. Therefore, due to the continuous nature of these processes, in case of overload phenomenon due to an incensement of the incoming wastewater flow-rate, the sedimentation time within the plurality of sedimentation compartment is decreased and a quality of the treated effluent is greatly reduced. On the other hand, in this exemplary embodiment, the second volume of each process vessels may result in maintaining the activated sludge mass over a period of at least 25 days lead to obtain the stabilized odorless activated sludge.

[0053] In one or more exemplary embodiments, the Mixed Liquor Suspended Solids (MLSS) may be increased to a high level due to carrying out of the process100in the semi-continuous mode as well as the integration of at least one sedimentation compartment within each of the at least three process vessels206,208,210.

[0054] In one or more exemplary embodiments, the Mixed Liquor Suspended Solids (MLSS) may be in a range of 5000 to 7000 mg / L. A higher level of the MLSS causes increasing a tolerance of the process vessels206,208,210to overloading and organic and chemical shocks, for example, but are not limited to, sudden pH changes. On the other hand, the Mixed Liquor Suspended Solids (MLSS) higher level may lead to an increment in a ratio of a receiving volume to an incoming wastewater volume, as a result of which the disclosed process100can withstand the chemical and organic shocks up to 4 times its nominal capacity.

[0055] In one or more exemplary embodiments, an aeration rate to the first process vessel206may be different from an aeration rate to the second process vessel208as well as to the third process vessel210, so this difference in the aeration rate to each of the first, second, and third process vessels206,208,210result in production of a various amount of the activated sludge in each process vessel that the amount of the produced activated sludge depends on a concentration ratio of the biological oxygen demand and the chemical oxygen demand.

[0056] In another exemplary embodiment, the aeration rate into the first process vessel206, the second process vessel208, and the third process vessel210may be in a same level.

[0057] In one or more exemplary embodiments, a nitrogen-containing compounds in the incoming wastewater may be removed during the steps104and108of process100through converting the ammonium ions to nitrite and nitrate ions in step104due to the aerating into the incoming wastewater within the process vessels206,208,210and the conversion of the nitrate ions to the nitrogen molecules in step108as a result of the anaerobic reactions, so the nitrogen molecules leave the environment of the process vessels206,208,210in a neutral and healthy way. In these embodiments, the aeration into the first process vessel206, the second process vessel208, and the third process vessel210and the aeration stopping may be periodically performed utilizing the control unit212of the wastewater treatment system. Although, in the MBBR and A2O processes, due to the continuous nature of these processes, it is not possible to perform an anaerobic state in the aeration process vessels.

[0058] In an exemplary embodiment, a total volume of the process vessels206,208,210may comprise a third volume in each of the first, second, and third process vessels206,208,210that may configure to provide an extra space to prevent stopping or incompletion of the treating wastewater process100due to overloading phenomena of the incoming wastewater stream. Additionally, the third volume may provide a suitable level of the Mixed Liquor Suspended Solids (MLSS) to complete the biological reaction that is required for treating the extra volume of the incoming wastewater stream. While, in MBBR or A2O processes, there is no extra volume to accommodate an additional wastewater stream during a high load to provide a sufficient air required to complete the wastewater treatment reactions. Therefore, in these conditions, the mixture of the incoming wastewater without completing the biochemical reactions and the un-stabilized sludge are forced to leave the process vessels that can strongly affect the quality of the treated effluent as well as a nitrogen removal quantity of the treated effluent. Furthermore, the Mixed Liquor Suspended Solids (MLSS) in these processes is designed and calculated at a low level; Therefore, with the smallest increase in the incoming wastewater stream, the systems cannot tolerate the decomposition of an additional organic load, which itself leads to a production of unpleasant odors.

[0059] In an exemplary embodiment, the plurality of process parameters that may control utilizing the control unit212may comprise a desired amount of nitrate compounds in the clarified effluent, an aeration rate into each of the process vessels, a time for stopping the aeration, and a number of alternating cycles of the aeration and stopping aeration.EXEMPLE 1: TREATMENT OF A WASTEWATER

[0060] InExample 1, treatment of a wastewater through an exemplary process was carried out utilizing the exemplary system, consistent with one or more exemplary embodiments of the present disclosure. In this example, consistent with the exemplary wastewater treatment process100of, an incoming wastewater enters the exemplary separating compartment204and a plurality of large and untreatable object are separated utilizing the exemplary mounted grid2042within the exemplary separating compartment204. Following that, the incoming wastewater is directed to the first process vessel206, the second process vessel208, and the third process vessel210by passing through the first and second apertures embedded in the first barrier205and the second barrier207and the incoming wastewater stream contacts to the at least one microorganism102.The first process vessel206plays a main role for treating the incoming wastewater stream, so a higher aeration rate is applied to the first process vessel206utilizing the at least one air blower. Therefore, following that, a different aeration rate was blown into the first, second, and third process vessels206,208,210in order to activate the at least one microorganism104. Then, a biological reaction between the activated microorganism and the incoming wastewater for purifying the incoming wastewater106and forming the plurality of activated sludge aggregate was took place. Afterward, the air blowing mechanism was stopped to remove a plurality of nitrate compounds and convert them to the plurality of nitrogen molecules108. The steps106and108was repeated periodically to reach a high efficiency of purification as well as nitrate ions removal. Following that, sedimentation of the plurality of activated sludge aggregates resulting from activation of the at least one microorganism110was occurred. After 12 hours of starting the exemplary process100, the produced clarified effluent was discharged112from the exemplary third process vessel210without stopping the exemplary process100. After 25 days or more of starting the process100, the stabilized odorless activated sludge can be discharge from each of the exemplary first, second, and third process vessel206,208,210.

[0061] A desired amount of nitrate compounds in the clarified effluent, a aeration rate into each of the process vessels, a time for stopping the aeration, and a number of alternating cycle of the aeration and stopping aeration are controlled online and automatically utilizing the exemplary control unit212of the wastewater treatment system200.

[0062] While particular aspects of the present subject matter described herein have been shown and described, it will be apparent to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this subject matter described herein and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this subject matter described herein. Furthermore, it is to be understood that the invention is solely defined by the appended claims. It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one”, to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and / or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations or two

[0063] It will be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein. Relational terms such as first, second, and third and the like may be used solely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” “include,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, apparatus, or device that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, apparatus, or device. An element proceeded by “a” or “an” does not, without further constraints, preclude the existence of additional identical elements in the process, method, article, or device that comprises the element. Moreover, “may”, “can” and other permissive terms are used herein for describing optional features of various embodiments. These terms likewise describe selectable or configurable features generally, unless the context dictates otherwise.

Claims

A process for treating a wastewater, comprising:i) contacting an incoming wastewater stream with at least one microorganism in at least three process vessels;ii)activating the at least one microorganism by an air blowing mechanism into the at least three process vessels for at least one time;iii) purifying the incoming wastewater by carrying out a reaction between the activated microorganism and the incoming wastewater;iv) reducing a nitrate pollution of the incoming wastewater by carrying out at least one time an anaerobic process through stopping the air blowing mechanism into the at least three process vessels;v) sedimentation of a plurality of activated sludge aggregates resulting from activation of the at least one microorganism;vi) discharging a clarified effluent after a sufficient time; andvii) discharging a stabilized odorless activated sludge after at least 25 days,wherein the process is carried out in a semi-continuous mode.The process according to claim 1, further comprising eliminating a plurality of objects by passing the incoming wastewater stream through at least one separating compartment before entering the incoming wastewater into the at least three process vessels.The process according to claim 1, wherein a higher aeration rate into a first process vessel of the at least three process vessels is applied compared to a second process vessel and a third process vessel of the at least three process vessels.The process according to claim 1, wherein an aeration rate into a first process vessel, a second process vessel, and a third rector of the at least three process vessels is in a same level.The process according to claim 1, wherein the steps ii), iv), v), and vii) are performed in a same time in a first, second, and third process vessels of the at least three process vessels wherein the at least three process vessels are hydro-dynamically connected to each other.The process according to claim 1, wherein a level of aeration rate into a first, a second, and a third process vessels of the at least three process vessels is reduced byorof a primary level of aeration rate, when an incoming wastewater flow rate into the at least three process vessels is reduced.The process according to claim 1, wherein the sufficient time for discharging the clarified effluent is at least 12 hours in accordance with a flow rate of the incoming wastewater.The process according to claim 1, wherein steps ii) and iv) are periodically performed in order to further remove nitrate pollution of the incoming wastewater.A system to perform a wastewater treatment process comprising:at least three process vessels configure to perform the treating wastewater process;at least one air blower configure to provide a sufficient amount of oxygen for activating at least one microorganism; andat least one control unit configure to control a plurality of process parameters,wherein the at least three process vessels are chemically different from each other while the at least three process vessels are hydrodynamically connected with each other.The system according to claim 9, further comprising at least one wastewater inlet, at least one separating compartment configure to eliminate a plurality of objects from an incoming wastewater stream, at least one outlet configures to discharge a stabilized activated sludge, and at least one conduit configures to discharge a treated effluent.The system according to claim 10, wherein the separating compartment comprises a first channel and a second channel configures to eliminate the plurality of objects, wherein during a periodic service of the system without a need to turn the system off, an entrance of the incoming wastewater into the first channel or the second channel in order to discharge a mass of a plurality of separated objects is cut off.The system according to claim 9, wherein a first process vessel of the at least three process vessels is separated from a second process vessel of the at least three process vessels utilizing a first barrier and the second process vessel of the at least three process vessels is separated from a third process vessel of the at least three process vessels utilizing a second barrier, wherein a first opening mounted within the first barrier and a second opening mounted within the second barrier are hydrodynamically connected the first process vessel to the second vessel and the second process vessel to the third process vessel, respectively.The system according to claim 12, wherein a total volume of each process vessel comprises a first volume configure to carry out at least one biological reaction for the treatment of the incoming wastewater, a second volume configure to sediment of the activated sludge mass while the treating wastewater process is carried out, and a third volume configure to provide an extra space to prevent stopping or incompletion of the treating wastewater process due to an overloading phenomena of the incoming wastewater.The system according to claim 9, wherein each process vessel of the at least three process vessels comprise a reacting portion configure to carry out at least one biological reaction for the treatment of the incoming wastewater.The system according to claim 9, wherein each process vessel of the at least three process vessels comprise a sedimentation portion configure to sediment of the activated sludge mass while the treating wastewater process is carried out.The system according to claim 9, wherein each process vessel of the at least three process vessels comprise a portion configure to provide an extra space to prevent stopping or incompletion of the treating wastewater process due to overloading phenomena of the incoming wastewater.The system according to claim 9, further comprising a second conduit configure to return a portion of the activated sludge mass from the third process vessel to the first process vessel in order to supply a suitable concentration of the activated microorganism.The system according to claim 9, wherein a duration of discharging a stabilized odorless activated sludge mass from the at least three process vessels is after at least 25 days.The system according to claim 9, wherein a duration of discharging a clarified effluent from the at least three process vessels is at least 12 hours according to a flow rate of the incoming wastewater.

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