Patent Application
20190263696
The disclosure relates generally to water, reuse and wastewater treatment and, more particularly, to removal of constituents from water in water systems.
Biofilm systems have traditionally been used in wastewater treatment and more recently have received increased attention in reuse and drinking water systems. These biofilm systems have often been approaches where management of diffusion was of low priority with a greater focus being placed on providing support for organisms at a high enough solids retention time (SRT), and typically more SRT is better.
According to a non-limiting aspect of the disclosure, a technological solution is provided for removing constituents from water and providing an effluent having low turbidity and low pollutant residual. The technological solution includes a system, an apparatus and a methodology for treating water to achieve low turbidity, low chemical oxygen demand, low total organic carbon, or low pollutant residual. The technological solution includes an application of a reactant followed by a biofiltration system, among other things. The technological solution includes application of one or more chemical reactants (for example, oxidants or reactants) in combination with a biofilm system in water treatment.
According to a non-limiting example of the technological solution, an apparatus is provided for removing constituents from an influent. The apparatus comprises: a biological processor that receives a water mixture as influent and outputs a liquor; a solid-liquid separator that receives the liquor and separates the liquor into a liquid and a solid; and a biofilm media that includes at least one media surface, the biofilm media having a biofilm mass, biofilm volume, biofilm density, biofilm thickness, hydraulic retention time or solids residence time, wherein the at least one media surface grows a biofilm that removes one or more constituents contained in the influent, and wherein the biofilm mass, biofilm volume, biofilm density, biofilm thickness, hydraulic retention time or solids residence time is controlled by at least one of a physical process, a biological process or a chemical process.
The biological processor can comprise a bioreactor or a biofiltration system.
The biofilm media can have two or more media surfaces, each media surface having a different biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time. At least one of the two or more media surfaces can be sheltered, partly sheltered, or unsheltered.
The biofilm media can include at least one of a ridge, a grid, a macro-pore inclusion, or a micro-pore inclusion on at least one of the two or more media surfaces or within the biofilm media.
The apparatus can comprise: a pretreator that applies a chemical agent such as ozone, chlorine, ultraviolet radiation, hydrogen peroxide, potassium permanganate or a biological agent to the influent or a recycle stream, wherein the chemical agent comprises a reactant, an oxidant, or a reductant, wherein the biological agent comprises a phage, a vector or a virus, and wherein the physical process or biological process comprises adding the chemical agent or the biological agent to the influent or recycle stream to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time. The chemical agent can include ozone, hydrogen peroxide, ultraviolet radiation, or potassium permanganate.
The apparatus can further comprise an augmentor that adds a nutrient or a cofactor to the influent or a recycle stream, wherein the nutrient comprises a trace element, nitrogen or phosphorous, wherein the cofactor comprises an organic coenzyme or an inorganic metal, and wherein the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time is controlled by the nutrient or cofactor. The inorganic metal can include iron, zinc, or copper.
The apparatus can further comprise a selector that applies the physical process by shearing the biofilm media to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time and also perform solids classification as needed.
The apparatus can further comprise a gas source that applies the physical process by scouring the biofilm media to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time.
The apparatus can further comprise a backwashing device that applies the physical process by backwashing the biofilm media to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time.
The constituents can comprise at least two of a micropollutant, a nanopollutant, a carbonaceous material, a nutrient, or an inorganic compound.
The biological processor can comprise a bioreactor and the biofilm media can comprise two or more carriers.
The apparatus can further comprise a controlled biofilm zone comprising a first carrier of the two or more carriers; and an uncontrolled biofilm zone comprising a second carrier of the two or more carriers, wherein a biofilm growing on the second carrier is sheared by the first carrier within the uncontrolled zone.
According to another non-limiting example of the technological solution, a method is provided for removing constituents from an influent, the method comprising: receiving a water mixture as influent; treating, by a biological processor, the influent to output a treated liquor; separating a solids mixture from the treated liquor; and controlling a biofilm mass, biofilm volume, biofilm density, biofilm thickness, or a solids residence time of a biofilm comprised in at least one media surface provided by a biofilm media to grow and remove one or more constituents contained in the influent, wherein the controlling the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or the solids residence time comprises at least one of a: applying a physical treatment process; applying a biological treatment process; or applying a chemical treatment process.
In the method, the biofilm media can include at least one of a ridge, a grid, a macro -pore inclusion, or a micro-pore inclusion on the at least one media surface or within the biofilm media. The biofilm media can have two or more media surfaces, each media surface having a different biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time. The method separating the solids mixture from the treated liquor can comprise applying a membrane, a filter, a clarifier or a hydrocyclone to the liquor.
In the method, the chemical treatment process can comprise adding a chemical agent or a biological agent to a recycle stream, wherein the chemical agent comprises a reactant, an oxidant, or a reductant, wherein the biological agent comprises a phage, a vector or a virus, and wherein the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time is controlled by the chemical agent or biological agent. The chemical agent can include ozone, chlorine, hydrogen peroxide, ultraviolet radiation, or potassium permanganate.
In the method, the biological treatment process can comprise adding a nutrient or a cofactor to a recycle stream, wherein the nutrient comprises a trace element, nitrogen or phosphorous, wherein the cofactor comprises an organic coenzyme or an inorganic metal, and wherein the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time is controlled by the nutrient or cofactor. The inorganic metal can include iron, zinc, or copper.
In the method, the physical treatment process can comprise applying a shearing force to the biofilm media by a solid-liquid separator to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time; scouring the biofilm media by a gas to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time; or backwashing the biofilm media to control the biofilm mass, biofilm volume, biofilm density, biofilm thickness, or solids residence time.
Additional features, advantages, and embodiments of the disclosure may be set forth or apparent from consideration of the detailed description and drawings. Moreover, it is to be understood that the foregoing summary of the disclosure and the following detailed description and drawings provide non-limiting examples that are intended to provide further explanation without limiting the scope of the disclosure as claimed.
The accompanying drawings, which are included to provide a further understanding of the disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the detailed description serve to explain the principles of the disclosure. No attempt is made to show structural details of the disclosure in more detail than may be necessary for a fundamental understanding of the disclosure and the various ways in which it may be practiced.
The present disclosure is further described in the detailed description that follows.
The disclosure and its various features and advantageous details are explained more fully with reference to the non-limiting embodiments and examples that are described or illustrated in the accompanying drawings and detailed in the following description. It should be noted that features illustrated in the drawings are not necessarily drawn to scale, and features of one embodiment may be employed with other embodiments as those skilled in the art would recognize, even if not explicitly stated. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the embodiments of the disclosure. The examples are intended merely to facilitate an understanding of ways in which the disclosure may be practiced and to further enable those skilled in the art to practice the embodiments of the disclosure. Accordingly, the examples and embodiments should not be construed as limiting the scope of the disclosure. Moreover, it is noted that like reference numerals represent similar parts throughout the several views of the drawings.
Industrial, agricultural or residential practices can release a variety of constituents in water. The micropollutants can be harmful to animal health if not properly removed or disposed. The constituents can include, for example, organic contaminants, inorganic contaminants, micropollutants, nanopollutants, chemical compounds, pesticides, drugs, cleaning products, or industrial chemicals, which can be toxic to animal health, including human health. Some of the constituents can bioaccumulate in living organisms such as humans, resulting in serious harm to the organisms.
A biological treatment process can be used to remove constituents from water. The biological treatment process can be used in, for example, wastewater treatment, drinking water treatment, water reuse, distribution systems for drinking water, collection systems for wastewater, residential or institutional plumbing, natural or constructed wetlands, storm water treatment, agricultural buffers, or river bank filtration systems. Biological treatment can be carried out by microorganisms such as, for example, bacteria, mold, fungi, protozoa (for example, amoebae, flagellates, or ciliates), algae, metazoa (for example, rotifiers, namatodes, or tardigrades), or prokaryotes (for example, alphaproteobacteria, betaproteobacteria, gammaproteobacterial, bacteroidetes, or actinobacteria). The microorganisms can remove carbon or nutrient from the water by employing various metabolic or respiratory processes. Biodegradable organic material can be biochemically oxidized by, for example, heterotrophic bacteria under aerobic conditions, or under anaerobic conditions by, for example, methanogenic archaea.
The technological solution can include a biofilm system, a water treatment apparatus or a water treatment process for removing constituents from water, including, for example, wastewater. The technological solution can include a biofilm system that facilitates or carries out biodegradation of constituents in a water treatment apparatus (such as, for example, a water treatment apparatus shown in any of
The technological solution can include a solid-liquid separator or a solid-liquid separation process that can be combined with a biological processor or a biological treatment process. The solid-liquid separator or processor can manage concentration of constituents or turbidity in the effluent output from the technological solution. Since the growth function of biofilms to degrade constituents (such as, for example, complex substrates or pollutants) can run counter to solid-liquid separation in water treatment systems or processes, the technological solution provides a mechanism for optimizing biofilm growth and solid-liquid separation to provide an effluent that can meet or exceed water purity requirements for human consumption, or for discharge into the environment, such as, for example, in a stream, a river, a wetland, or an ocean. Additionally, there are influent characteristics that could result in constituents being degraded at different rates. The biofilm system and process in the technological solution can include a plurobiolm having multiple (for example, two or more) biofilm surfaces to degrade constituents with different degradability rates and to support microorganisms needing different SRTs, thereby providing a comprehensive solution for, not only managing biofilm thicknesses (or the underlying diffusion or their relative SRT management), but also the solid-liquid separation process. The technological solution provides a comprehensive solution for achieving low turbidity and low pollutant residual in effluent. The technological solution can provide an effluent having, for example, a turbidity level of 0.05 nephelometric turbidity units (NTU) or less, and in the influent, a color of about 20 to 60 mgPt/L (in Platinum Cobalt Units on the Hazen Scale), and a TOC of about 0.2 to 10 mg/L. The technological solution can achieve residual levels or concentrations of constituents in the effluent safe for human consumption or for discharge into the environment. Turbidity can be measured using, for example, a turbidimeter.
The technological solution can include, among other things, a step of applying a reactant, such a, for example, a chemical, followed by a biofilm media or floc system contained in a membrane reactor, or the application of a reactant, such as, for example, a chemical like chlorine or a gas such as ozone, followed by a biofilm system. The technological solution can include a roughing media to degrade a readily degradable organic material that is made labile by the reactant, followed by a downstream media that can be used to degrade more refractory substrates. The two media can remove turbidity associated with the solid-liquid separation function.
The biofilm system includes biofilms that facilitate degradation in constituents such as, for example, total organic compounds (TOC), micropollutants or nanopollutants. The biofilm system can effectively and efficiently remove constituents from water. The technological solution can manage and control effluent properties such as, for example, turbidity, pH level, or constituent concentration levels. The technological solution can manage and control film thickness(es) or biomass(es) in a manner that can provide exceptional effluent quality without a treatment system or process becoming biomass (SRT) limiting or turbidity limiting. For instance, the technological solution can be used in treating wastewater to output a final effluent that meets or exceeds quality standards for human consumption or for discharge in the environment.
As noted above, the biofilm system can include a monobiofilm or a plurobiofilm having two or more media surfaces for growing different (or the same) types of biomasses. The plurobiofilm can include sheltered, partly sheltered or unsheltered biofilms. The biofilm(s) can be controlled or uncontrolled. The biofilm(s) can be thin or thick, or tailored for specific degradation of constituents or to otherwise support slowly or more readily growing organisms. The technological solution can manage and control turbidity or a solid-liquid separation process that can be decoupled from the biofilm management process.
As seen in
In the biofilm system, the biofilm thicknesses can range anywhere from, for example, about 5 μm (or less) to about 50 μm for a thin biofilm, and from about 50 μm (or less) to about 500 μm for a thick biofilm. The biofilm, along its thickness, can include anywhere from, for example, five (or fewer) numbers of microorganisms (end-to-end) to fifty (or more) microorganisms. Each biofilm thickness should be such that it can be actively managed to minimize turbidity or constituents in the effluent. Readily biodegradable constituents tend not to be too limited by biomass, as seen in the curve A in
According to a non-limiting example of the disclosure, a biofilm can be grown in a shelter or an inclusion such that the biofilm can self-regulate its biomass and biofilm thickness. This self-regulation can address temperature changes or mass loading changes. The self-regulated biofilm can have a higher SRT compared to a non-self-regulated biofilm. The higher SRT can facilitate growing or degrading a difficult to degrade constituent in a shelter, such as, for example, an unrestricted self-regulated SRT shelter. A substrate, a micronutrient or a co-substrate provision can be included in or applied to the biofilm, or provided through an annulus of a porous biofilm support to facilitate growth. The self-regulated or sheltered biofilm can have more diffusion resistance than an unsheltered, actively managed biofilm that can be used to degrade readily degradable constituents, or constituents that have a larger mass or concentration. This can allow for microorganisms that use readily or more easily degradable carbons or substrates to preferentially coexist in low diffusion conditions, since microorganisms will prefer to locate in conditions of low diffusion to access substrates more easily. The more difficult to degrade constituents can be degraded or grown on a slightly more diffusion resistant biofilm. The thickness of the more diffusion resistant biofilm can depend on the thickness of the more actively managed biofilm.
The thicknesses of the biofilms can be managed in series or in parallel, or any combination of in series or in parallel, or in a tributary or distributary configuration. For example, an actively managed biofilm can be a roughing biofilm that precedes a sheltered biofilm that is passively managed. In one example, an actively managed biofilm can consist of anthracite or expanded clay on top of a granular activated carbon (GAC) that consists of shelters. The anthracite or expanded clay can be actively scoured or backwashed to manage biofilm thickness and SRT, while the GAC can support the degradation of constituents. The actively managed biofilm can be used to control effluent solids and turbidity through scouring or one or more backwash cycles. The vice-versa can also take place, depending on the application of the technological solution.
In a non-limiting example of the technological solution, a monofilm can be included in a depth or a length of a reactor (for example, a bioreactor 40 shown in
The Ks can be lowered by making the biofilm thinner. This can be achieved by, for example, increasing a surface area for a biofilm to grow, thereby allowing the biomass to spread out over a larger surface area. This can also be achieved by a plurobiofilm that includes two or more biofilms in the biofilm system, including a thin unsheltered biofilm with a managed SRT for the faster degrading substrates, and a slightly thicker sheltered biofilm to grow the longer SRT needing substrate. According to a non-limiting example of the biofilms system, the thinner unsheltered biofilm can have a thickness of about 5 μm (or less) to about 50 μm (or less), and the thicker sheltered biofilm can have a thickness of about 10 μm to about 500 μm. These two approaches can provide for a decrease in Ks and a decrease in the self-regulated biofilm thickness and effluent concentration. The Ks can be, for example, about 10 μg/L to about 100 μg/L for constituents.
According to a non-limiting example of the disclosure, the biofilm system can be included in a wastewater treatment process to remove constituents from influent wastewater. In wastewater treatment processes, an increase in constituent concentrations in effluent from summer to winter can occur due to an increase in thickness of a biofilm, which can result in an increase in diffusion resistance and an increase in Ks and thus a movement of the minimum point, as seen in
It is noted that in this specification, wherever a description is provided in terms of thickness associated with a biofilm, the term applies equally to a biofilm mass, biofilm volume, or a biofilm density, but the dimensions of mass, volume or density will need to be appropriately proportioned, as understood by those skilled in the pertinent art. Any implementation of a biofilm can include arrangements of two or more biofilms arranged in series, in parallel, in tributary (for example, where additional flows such as a bioaugmentation, co-substrate, or micronutrient are added to a downstream reactor) or in distributary (for example, where flow from one reactor is distributed into two or multiple parallel reactors) configurations. A distributary configuration can be particularly beneficial where a small roughing reactor is used to degrade easy to degrade but high mass pollutants followed by either a larger reactor or multiple downstream reactors. The reactors can precede a solid-liquid separator (SLS), which can include a device or a process. Instead of reactors, one or more filters (such as, for example, BF 41 shown in
The reactor (or filter) can be preceded by either a chemical oxidation step or device, a chemical reduction step or device, a rapid mix or flocculation step or device that adds a coagulant or a flocculant, a mixing step or device that adds or mixes in a biofilm support media (such as, for example, powdered activated carbon, granular activated carbon, or any material with reactive properties), a mixing step or device that adds or mixes in a biofilm support media for biofilm attachment, a mixing step or device that adds or mixes in a biofilm support media for biofilm ballasting, a pre-settling step or device, or an equalization step or device. These preceding steps or devices can be configured as a single process or device, or multiple processes or devices. Depending on the biodegradability of a constituent, a differentiation in solids retention times might be needed while maintaining the thin biofilm to support a bulk effluent constituent concentration. The graph in
As seen in
A device such as a hydrocyclone or an air scouring device, or other approaches to scour or shear the biofilm can be used to physically manage thickness. Exposure of biofilms to a microbe specific toxicant, inhibitor, co-substrate (especially to degrade a refractory pollutant), enzymes, cofactors or other nutrients can also be used to chemically control the biofilm. Biological control can be used in the form of microbe specific phage or biological vector, or bioaugmented organisms for biofilm thickness and composition control. Analyzers or other instrumentation (manually or on-line) can be used to monitor or control the biofilm mass, volume, density or thickness, directly or indirectly. For instance, the effluent can be monitored and constituent concentration measured and, based on measurement results, shearing or scouring of the biofilm(s) can be controlled to adjust the constituent concentration in the effluent to predetermined values. Surrogates for biofilm thickness, mass, volume or activity measurement, such as, for example, using adenosine triphosphate (ATP), respirometry, optics or acoustics, can also be used.
The apparatus can include a post-filtration device (PF) 60 or a disinfector (D) 70. The PF 60 or D 70 can be located downstream of the SLS 50, as seen in
The apparatus can include a pretreator 80, a selector 90, or an augmentor 95. An input of the pretreator 80 can be connected to an output of the SLS 50. The pretreator 80 can be configured to receive gravity-selected constituents from the SLS 50 at its input and apply a chemical, biological or physical treatment process on the input constituents to output pretreated constituents at an output. The output can be connected to an input of the selector 90. The
The selector 90 can be configured to receive the pretreated constituents at its input and separate constituents based on, for example, density or size. The selector 90 can include the gravimetric selector 11 in U.S. Pat. No. 9,242,882, titled “Method and Apparatus for Wastewater Treatment Using Gravimetric Selection,” or the gravimetric selector 260 in U.S. Pat. No. 9,670,083, with disclosures in both patents being incorporated herein in their entireties by reference. The selector 90 can select larger or denser constituents from smaller or less-dense constituents and output the larger or denser constituents at a first output to the augmentor 95 (or directly to the BP 40) and the smaller or less-dense constituents at a second output as waste 92.
An input of the augmentor 95 can be connected to the first output of the selector 90, and an output can be connected to the BP 40. The augmentor 95 can be configured to apply bioaugmentation, nutrients, or cofactors to the received constituents before outputting augmented constituents at an output to be supplied to the BP 40.
The AOP 10 can include a device that implements an oxidation or reduction method, including, for example, an aqueous phase oxidation method. The method can consist of a highly reactive component that can be used in the oxidative destruction of target pollutants. The reactive component can include, for example, ozone (O3), ultra-violet (UV), or hydrogen peroxide. The component can be applied to the influent wastewater 5 to destroy target pollutants and output a liquid flow having reduced pollutants.
The C/P 20 can include a device that implements a coagulation or flocculation method. The C/P 20 can include a device that can introduce natural or synthetic water-soluble compounds to, for example, a liquid flow input from the AOP 10. The compounds can include one or more polymers, such as, for example, macromolecular compounds that have the ability to destabilize or enhance coagulation or flocculation of the constituents in the liquid flow. The compounds can be included in solid or liquid form.
The PAC 30 can include a device that includes a coagulation method, including, for example, a device that adds a poly-aluminum chloride-based coagulant or other coagulant that has, for example, low generation of waste sludge in a wide pH range, event at varying temperatures (for example, at low temperatures). The PAC 30 can include a device that includes a filtration method. The PAC 30 can include, for example, powdered activated carbon (PAC) media or a granular activated carbon (GAC) medium.
The BP 40 can include a reactor, a bioreactor, or a plurality of reactors or bioreactors. The reactor can include a tank or a vessel. The bioreactor can include a biological treatment tank that can receive influent and contain a biological treatment process. The biological treatment process can include an aerobic biological treatment process or an anaerobic treatment process that can treat organic constituents in the influent. As seen in
The SLS 50 can include a clarifier, a settling tank, a cyclone, a centrifuge, a membrane, disc filter, or any other device or process that can separate solids from liquid. In the example seen in
The PF 60 can include a post-filtration device that includes a sand filter, granular activated carbon (GAC), powder activated carbon (PAC), biological-activated carbon (BAC) or any other mechanism for biological degradation or adsorption of constituents.
The D 70 can include a device that disinfects an influent. The device can include a device that applies a gas or radiant energy to the influent. The radiant energy can include, for example, energy having a frequency in the ultraviolet (UV) range of the spectrum. The gas can include, for example, ozone (O3).
The pretreator 80 can include a device that applies chemical pretreatment such as, for example, chemical coagulation. The pretreator 80 can include sedimentation unit (not shown), which can follow coagulation to sediment and remove of flocs or coagulants.
The pretreater 80 can include a device that applies biological pretreatment, such as, for example, adding a flocculent to maximize flocculent dispersion. The flocculant can include a polymer.
The pretreator 80 can include a device that applies physical pretreatment, such as, for example, a screen (not shown), a membrane (not shown), a clarifier (not shown), a cyclone (not shown), a centrifuge (not shown), or any other device or methodology that can separate solids from liquid or from other solids, or that can shear a biofilm from the support media. The pretreator 80 can include oxidation, nanofiltration, reverse osmosis filtration, or activated carbon filtration.
The selector 90 can include physical selector device such as, for example, a settling tank, a cyclone, a centrifuge, or any other device or process that can separate solids from liquid. In the example seen in
The augmentor 95 can include a device that applies a bioaugmentation process, or a nutrient or cofactor adding process. The augmentor 95 can include a devices that adds a combination of microbes, enzymes and cofactors to the constituents. The bioaugmentation process can include adding microorganisms that can, for example, biodegrade recalcitrant molecules in the constituents. The added microorganism can include a variety of different microorganisms that can biodegrade a variety micropollutants or nano-pollutants in the constituents. The augmentor 95 can include a device that adds one or more types of nutrients or cofactors to the constituents to promote enrichment and growth of microorganisms. The cofactors can include enzymes such as, for example, proteinic enzymes, proteidic enzymes, or any other cofactors that can promote enrichment and growth of the microorganisms.
As seen in
In the apparatus in
After the solid-liquid separation (for example, SLS 50) a filtration step (for example, PF 60) can be added, which can include, for example, sand filtration, GAC, BAC or other filtration technologies. A disinfection step (for example, D70) can follow the filtration step. The disinfection step can include a technology such as application of UV energy on the effluent line.
According to one or more non-limiting examples of the technological solution (including, for example, the apparatus in any of
treatment apparatus constructed according to the principles of the disclosure. This apparatus is similar to the apparatus in
As seen in
In
In
Referring to
In
In
In
The BF 41 can include, for example, a continuous filtration system with internal cleaning. The BF 41 can include, for example, a discontinuous backwash filter. The BF 41 can include a biofilm system that includes a plurality of biofilms arranged in series, in parallel, a combination of in series and in parallel, a tributary configuration, or a distributary configuration to provide for specific and targeted substrate removal using chemical, physical or biological means. The tributary configuration can be implemented for growing specific biofilms or degrading specific pollutants. The distributary configuration can be implemented for managing or controlling hydraulic or solids loading rates or solids residence times.
As seen in the diagram in
When operating under optimal biofilm thickness for substrate 1 (fast rate), biomass limitation can occur for substrate 2 when the surface area is limited. In this case, at least two options might be available, including: (1) providing about 4 times more surface area to accommodate biofilm to remove substrate 2 at slower rate and thinner biofilm; or, (2) providing sheltered biofilm area where biofilm can be about 4 times thicker than optimal for substrate 2 to accommodate optimal kinetics for substrate 2 while managing substrate thickness for substrate 1 in non-sheltered biofilms and thus thinner biofilms.
Substrate removal rates can be determined by substrate type, concentration or organism growth rates on such substrate or environmental conditions impacting microbial growth, such as, for example, temperature, pressure, or availability of micronutrients.
If a change occurs in a biofilm structure or composition, the diffusion rate will be impacted and the dynamics between biofilm thickness and effluent concentration will change.
Effluent quality can be determined by diffusion kinetics when enough biomass or biofilm is present. The concentration can be dependent on the biofilm structure and thickness. Improving effluent quality can be done by managing biofilm thickness. When biomass is limited, decreasing EBRT can result in increased effluent quality as the apparatus (or process) is loaded higher than the substrate removal rates, which can be determined by diffusion. In case of biomass limitation, EBRT can be used as control parameter for effluent quality, which can be done to the determined effluent concentration set by the diffusion kinetics. The use of media with increased surface area can lead to management of biofilm thickness (diffusion) as a major control variable.
In the biofilm system according to the present disclosure, a biofilm thickness can be managed to have sufficient biomass to achieve target substrate degradation or effluent concentrations. As long as the effluent concentration decreases at increased biofilm thickness, biomass limitation can be apparent (for example, as shown in FIGA. 1A, 1B). An optimal biofilm thickness can be achieved at minimal effluent quality. Diffusion can become a major limitation when operating at thicker biofilms than optimal. Based on Fick's law of diffusion, effluent quality can increase linearly with biofilm thickness once a biofilm has enough area or volume to overcome biomass limitation. As a result, overall degradation rates can decrease rapidly with biofilm thickness.
According to a non-limiting example of the technological solution, a biofilm system can have multiple biofilms of distinct thicknesses and solids residence times for the removal of carbonaceous material, inorganic substrates, nutrients or micropollutants (or nanopollutants). At least one of the biofilms can be controlled to maintain a certain thickness (for example, between 0 and 500 μm). The latter can be achieved by selection of media with specified ridges or grids, allowing for the biofilm to meet a specified maximum thickness before being corrected by abrasion or by chemical or biological means. These structures can be diverse in shape, form, or grids, and can result from molding, casting or firing processes used to produce the media. In addition to the selection of specific media, physical abrasion, chemical treatment or the use of biological agents can be used to control biofilm thickness.
Multiple solids residence times can be maintained by managing the ratio of masses or volumes of multiple biofilm thicknesses, or by managing different tank volumes or hydraulic residence times for the multiple biofilms. Other methods for maintaining multiple solids residence times can include, for example, use of metabolic responses by the organisms degrading substrates or targeting degradation rates or residual substrate concentrations. This can be based on direct measurements, including concentration measurements of the target compound, or it can be based on surrogate measurements
A bulk liquid concentration or a surrogate measurement related to a limiting substrate concentration can be minimized or controlled by, for example, adjusting a flow or a mass rate or frequency of operation of a device or physical, chemical or biological mechanism controlling the biofilm thickness in the apparatus according to the principles of the disclosure.
The flow or mass rate, or the frequency of operation of the device controlling biofilm thickness can be increased as long as the bulk liquid concentration or its surrogate measurement is above a minimum concentration and the decreasing response in the bulk liquid concentration or surrogate measurement is observed. This can be based on achieving thinner biofilm without moving into biomass limitation (for example, as shown in
The biofilm can include an agglomeration of organisms. The biofilm can be a suspended floc, a granule or an attached growth biofilm.
The selection or out-selection of organisms can be managed by, for example, adjusting the biofilm thickness control device operation based on the product concentration. For example, in case of nitrifiers, nitrite can be used as an indicator to control biofilm thickness and out-select nitrite oxidizing organisms and select for ammonium oxidizing organisms. At decreased nitrite, and thus increased presence of nitrite oxidizing organisms, increased biofilm thickness control can be applied to target thinner biofilms to out-select nitrite oxidizing bacteria. In this example, ammonium can be used as a signal to make sure the mass of aerobic ammonium oxidizing organisms is not limited while out-selection other organisms. The same process can be applied to other examples where management of biofilm thickness can be used to out-select one organism from other, different organisms.
Niches can be created within a biofilm to provide a multifunctional biofilm. The control of biofilm thickness can allow for balancing of the different functions or to control competition between organisms. Through biofilm thickness control, the mass and content of the organisms residing on the surface of the biofilm can be affected. The organisms can include aerobic organisms and their location within the biofilm can be driven by oxygen gradients or anoxic. The organisms can include anaerobic organisms where electron donors or competitive substrates can control their location within the biofilm.
The flow or mass rate or frequency of the operation of a device controlling the biofilm thickness can be adjusted based on, for example, head loss or pressure differential. Head loss is often a good surrogate measurement for increased turbidity or increased biofilm thickness. However, in some cases head loss might be an earlier limitation of filters (or turbidity) than diffusion limitation, thus causing potentially biomass limitation when control is based on head loss. It is thus important to balance overall physical throughput limitation with biomass limitation and diffusion limitation. Therefore, two different approaches may be available for managing turbidity or biofilm thickness, thus decoupling a main feature of solid/liquid separation and turbidity removal in a filter from biofilm thickness control, such as, for example, by using air scouring or other physical, chemical or biological means.
A surrogate measurement can be used to control biofilm thickness. The surrogate measurement can be based on, for example, pressure, fluorometry, spectrometry, a solute or gas concentration, or turbidity.
A target substrate for which a biofilm thickness or solids residence times is to be optimized can be an electron donor, electron acceptor or a carbon source.
A biofilm thickness can be controlled based on, for example, physically limiting a maximum biofilm thickness using specialized carriers or textiles that create grid, super structures or a certain porosity allowing different degrees of exposure to shear and substrate levels within one biofilm (such as, for example, the carrier 200 shown in
Multiple biofilm thicknesses can be created within a single carrier in which one or more biofilm thicknesses can be directly controlled through specified structures on the carrier. Uncontrolled biofilms can be feasible within protected areas of the carrier (for example, carrier 200, shown in
A carrier (or biofilm system) that can be used to create multiple biofilms can include, for example, powdered activated carbon, granular activated carbon, anthracite, sand, lava rock, green sand, ceramic media (for example, based at different temperatures), glass, expanded clay, calcified media such as sea shells, synthetic or plastic media, naturally occurring media, other impregnated or encapsulated natural or synthetic media, or a combination thereof. The media can contain special micro or macronutrients such as, for example, calcium, magnesium, iron, copper or other metals or catalysts, phosphorus, sulfur or other inorganics, or, light, heat, magnetic, or electromagnetic or radiation producing media that can change the rates of reaction within the biofilms. Encapsulated media can include specialized bacteria or organisms, such as, for example, fungi or algae, to degrade pollutants of concern. The encapsulation can be adjusted to manage or enhance pollutant sorption or adhesion characteristics by increasing surface attraction of the pollutant within the encapsulated material, thus making it more accessible to the encapsulated microorganism. Thus, the encapsulation can serve multiple purposes, such as, for example, for solid-liquid separation, protective coating for organisms, attracting substrates, managing diffusion characteristics, or sensing (such as, for example, sensing color change when a pollutant is internalized).
A device that can control a biofilm thickness can be based on or include managing shear or abrasion on the biofilm using mechanical or hydraulic approaches including but not limited to backwashing, flushing, scraping, air or water scouring, cyclones, or screens.
A device that can control the biofilm thickness can be based on or include controlled addition of chemicals such as oxidants, organic polyelectrolytes, inorganic coagulants, organic or inorganic flocculants, acids, bases, free nitrous acids, cations, anions, metal, nutrients, enzymes, ATP or other cofactors or growth promotors, growth inhibitors or toxicants.
A device that can control the biofilm thickness can be based on or include controlled addition of chemicals that can target a gross biofilm thickness or can specifically stimulate, inhibit or kill a certain organism or group of organisms including but not limited to heterotrophs, autotrophs, nitrifiers, denitrifiers, methanotrophs, manganese oxidizers, iron oxidizers, anaerobic methanogens or fermenters. These can include organisms with specialized abilities to degrade micropollutants.
The degradation of micro-pollutant can be controlled, for example, using bioaugmentation of acclimated biofilms or biomass or addition of specialized enzymes, cosubstrates or nutrients. Bioaugmentation products or other additives can be added for example at the end of the backwash cycle (as shown, for example, in
A device that can control biofilm thickness or solids residence time can be based on or include the out-selection of targeted organisms through mechanical shearing using cyclone or screens for removing an outer layer of the biofilm at a faster rate compared to the inner layers and thus uncoupling of sludge retention times. The device can maintain a maximum biofilm thickness formed on top of a carrier applied in the physical separated.
Application of a biofilm to physical forces within an external selector (for example, selector 90), such as, for example, screens or cyclones or within the device controlling biofilm thickness through abrasion, can result in the formation of denser biofilms that can impact the diffusion resistance and increase a microbial cell concentration within the biofilm.
A device for controlling a biofilm thickness can be based on substrate composition control through chemical processes such as ozonation, chlorination, chloramination, permanganate addition, peroxidation, vacuum, UV or other oxidation or advanced oxidation processes. Chemical reducing processes or advanced reducing processes can also be used (such as, for example, for refractory materials in a higher oxidation state), especially if the desire is to dehalogenate compounds or to reduce a complex oxidized chemical (for example, ringed compounds) that are resistant to further reactions. Reducing reactions can be achieved using reactive metals, hydrogen -based compounds, reducing radicals, electron or proton beams, or other chemicals. Substrate composition is typically the characteristics of a chemical or particle found in the influent that chemical processes can be modified to make the chemical more labile or biodegradable or to mix chemical and biological processes. The chemical process can also be applied during a backwash step or in the recycle (of clarified water or media) to create more targeted chemistries of refractory material in the water that have for example not degraded after a single pass of treatment. The chemical treatment can also be used to impact also the biofilm on the media that are subject to backwash or recycling (within reactors or between multiple reactors). These chemicals can be inhibitors or stimulants or cosubstrates or nutrients. These chemicals can also be any oxidant or reductant mentioned above.
The biofilms are maintained on filters, reactor vessels, polymeric or ceramic membrane reactors, deep clarifiers, fixed or moving bed processes, fluidized bed processes, trickling or biological aerated filters, continuous or intermittent backwash filters, fuzzy filters, cloth or fabric media, disc filters, membrane biofilm filters, or suspended processes or a combination of fixed and suspended processes.
A device that controls the biofilm thickness can be based on or include controlled addition of biological agents such as bacteria, fungi, algae, phages, protozoa or other higher life form predators, organisms or molecules that facilitate biofilm formation or microbial competition through quorum sensing or bioaugmentation to control gross biofilm thickness or microbial composition.
A biofilm thickness can be managed in, for example, a drinking water treatment plant, a water reuse plant, a distribution system for drinking water, a collection system for wastewater, a wastewater treatment plant, a plumbing system, a natural or constructed wetland, a storm water treatment system, an agricultural buffer, or a river bank filtration system.
A substrate concentration in a bulk or immediate boundary layer of a biofilm can be increased through physical or chemical approaches, including, but not limited to, charge attraction or repulsion, physical or chemical sorption, van der waals forces, proton gradients, or channeling for convection such as with activated carbon or extracellular polymeric substances. Sorption of carbonaceous material or of micropollutants onto extra cellular polymeric substances, activated carbon or other media, can create an increase in substrate concentration or driving force that can result in increased removal rates at increased biofilm thicknesses. Retention time of the compounds can be increased to allow for removal at decreased biomass content. Creating a combination of sorption with biological removal can result in increased substrate removal and achievement of decreased effluent concentrations.
The PAC or GAC can provide adsorption of organic or inorganic materials, including, for example, but not limited to, metals, micropollutants, organic carbon, non -biodegradable or recalcitrant organics.
Polyelectroytes, inorganic coagulants, flocculants or a combination thereof can be applied for coagulation of incoming particulate or colloidal material as a means of improving effluent quality or maintaining increased membrane permeability and flux, or, providing further support for biofilm growth.
Aeration can be included for membrane cleaning or to provide for oxygen transfer as an electron acceptor for biofilm growth or modulation or to maintain multiple biofilm oxidation states.
Sparged gas or electron acceptors such as hydrogen, nitrogen, carbon dioxide, or argon can be provided for membrane cleaning and control of oxidation-reduction potential and dissolved oxygen concentration.
A physical separator can be included to recover a biofilm support media (for example, the carrier 200, shown in
The physical separator can include a gravimetric device such as a cyclone, centrifuge, settler, screen, filter, or dissolved air floatation.
The physical separator can include an upstream shearing device to modulate biofilm thickness.
The physical separator can provide an inventory that is granular to maintain high membrane permeability and flux and that resists membrane fouling.
The media can provide scouring of the membrane filter surface to maintain high membrane permeability and flux and resist membrane fouling.
The membrane can be polymeric, ceramic or made of other inorganic material, cloth or other fibrous material such as a disc filter.
The membrane can be hollow fiber, flat sheet, flat plate, spiral wound or where the membrane is located in the reactor or in a separate membrane compartment with transfer of solids to and from the membrane tank.
The biodegradation of organics within the different apparatuses and processes can be enhanced with an upstream oxidation or advanced oxidation process. The oxidation can include ozone, UV, hydrogen peroxide, potassium permanganate, or any combination thereof. The biodegradation of organics containing halogens or other recalcitrant material can be enhanced using reducing or advanced reduction processes.
The biofilms can be optimized for growth of probiotic organisms for distribution system stability and for improving human health.
The membrane or filter can be replaced by a clarifier or solids contact clarifier that can return biomass, separated water, or a mixture of biomass and water to the bioreactor, or between two reactors, such as, for example, in internal recycle applications.
The backwash or air scour or surface wash can be applied at multiple levels or heights or depths to provide different solids residence times in a filter. The backwash and air scour can be used for differentiated turbidity removal (for example, of influent colloids OR solids) or for biofilm control (for example, by directly or indirectly controlling SRT). The differentiation can be used by for example focusing backwash for managing turbidity and using air scour for managing biofilms. This differentiation can be key to decouple different functions in a filter intended for managing micropollutants but also receiving a load of particulates and colloids and other material.
Chemicals can be applied to backwash water or the filter feed water to manage biofilm thickness along the depth of a filter.
According to a non-limiting embodiment of the technical solution, an apparatus is provided having a granular media filter preceded by another apparatus that promotes chemical oxidation or chemical reduction of flow entering the filter. The apparatus comprises a biofilm medial having two or more media surfaces carrying different biofilm mass, volume, density or thickness ranges or different solids residence times using sheltered, partly sheltered or unsheltered surfaces to grow biofilms for the removal of carbonaceous material, nutrients, inorganic compounds and/or micro-pollutants, wherein, at least one biofilm mass, volume, density or thickness range is managed using, ridges, grids, macro pore inclusions or micro pore inclusions on media surfaces or within the media, and/or chemical treatment or through the use of biological agents, and/or backwash, air scour or other physical means.
An example of the technological solution includes a method comprising a media -based filtration process that consists of two or more media surfaces carrying different biofilm mass, volume, density or thickness ranges or different solids residence time ranges for the removal of carbonaceous material, nutrients, inorganic compounds and/or micro-pollutants, wherein, at least one biofilm mass, volume, density or thickness is controlled using, ridges, grids or other casting, molding or firing processes, and/or, physical abrasion, chemical treatment or through the use of biological agents, or, at least one solids residence time is controlled by managing the ratio of masses or volumes of multiple biofilm thicknesses, and/or managing different reactor volumes or hydraulic residence times for the multiple biofilms, and/or, metabolic response by the organisms degrading substrates, and/or, targeting degradation rates or residual substrate concentrations, and/or using physical abrasion, chemical treatment or through the use of biological agents.
The biofilm thickness, mass, volume or density can be managed to have sufficient biomass to achieve target substrate degradation or removal rates or effluent concentrations.
The bulk liquid concentration or surrogate measurement related to the limiting substrate concentration can be minimized or controlled by adjusting the flow or mass rate or frequency of the operation of a device or physical, chemical or biological mechanism controlling the biofilm mass, volume or thickness.
The flow or mass rate or frequency of the operation of the device controlling biofilm thickness can be increased as long as the bulk liquid concentration or its surrogate measurement is above the minimum concentration and the decreasing response in bulk liquid concentration or surrogate measurement is observed.
A set-point concentration can be determined above the minimum bulk liquid concentration or surrogate measurement concentration required to maintain the minimum mass of active organisms for substrate degradation.
The selection or out-selection of organisms can be managed by adjusting the biofilm thickness control device operation based on the product concentration; or, where the biofilm mass, volume or thickness is controlled based on physically limiting the maximum biofilm mass, volume or thickness using specialized carriers or textiles that create grid, super structures or a certain porosity allowing different degrees of exposure to shear and substrate levels within one biofilm; or, where multiple biofilm mass, volume or thicknesses are created within a single media or carrier; or where the biofilm is made of self-agglomerating organic and inorganic material in the form of granules, flocs or other structures.
The flow or mass rate or frequency of the operation of a device controlling the biofilm mass, volume or thickness can be adjusted based on head loss or pressure differential.
The surrogate measurement can be pressure, fluorometry, spectrometry, a solute or gas concentration, or turbidity.
The substrate can be an electron donor, electron acceptor or a carbon source.
The carriers can be powdered activated carbon, granular activated carbon, plastic media, ceramic media, sand, anthracite, sponges, rocks, chitin, shells, anthracite, sand, lava rock, glass, expanded clay, green sand, calcified media such as sea shells, synthetic or plastic media, naturally occurring media, other impregnated or encapsulated natural or synthetic or a combination thereof media, media containing special micro or macronutrients such as calcium, magnesium, iron, copper or other metals, phosphorus, sulfur or other inorganics, or, light, heat, magnetic, or electromagnetic or radiation producing media.
The device controlling the biofilm mass, volume or thickness can be based on managing shear or abrasion on the biofilm using mechanical or hydraulic approaches including but not limited to backwashing, flushing, scraping, air or water scouring, cyclones or screens.
The device controlling the biofilm mass, volume or thickness can be based on controlled addition of chemicals such as oxidants, organic polyelectrolytes, inorganic coagulants, organic and inorganic flocculants, acids, bases, free nitrous acids, cations, anions, metal, nutrients, enzymes, ATP or other cofactors or growth promotors, growth inhibitors or toxicants; and, where the chemicals can be applied to the backwash water or the filter feed water to manage biofilm thickness along the depth of the filter.
The device controlling the biofilm mass, volume or thickness can be based on controlled addition of chemicals that can target the gross biofilm mass, volume or thickness or can specifically stimulate, inhibit or kill a certain organism or group of organisms including but not limited to heterotrophs, autotrophs, nitrifiers, denitrifiers, methanotrophs, manganese oxidizers, iron oxidizers or reducers, sulfur oxidizers or reducers, anaerobic methanogens or fermenters.
The degradation of micro-pollutant can be controlled using bioaugmentation of acclimated biofilms or biomass or addition of specialized enzymes, cosubstrates or nutrients.
The device controlling biofilm thickness and/or solids residence time can be based on the out-selection of targeted organisms through mechanical shearing using cyclone or screens removing the outer layer of the biofilm at a faster rate compared to the inner layers and thus uncoupling of sludge retention times.
The composition of the influent to filtration can be controlled through oxidation or pre-oxidation process such as ozonation, chlorination, chloramination, permanganate addition, peroxidation, ultra violet or other advanced oxidation processes, or through reduction or pre -reduction process associated with a reducing agent.
The biofilms filters can be fixed or moving bed systems and reactors, fluidized bed filters, trickling or biological aerated filters, continuous or intermittent backwash filters, fuzzy filters, cloth or fabric media, disc filters, membrane biofilm filters or, a combination of fixed and suspended processes.
The device controlling the biofilm thickness can be based on controlled addition of biological agents such as bacteria, phages, protozoa or other higher life form predators, organisms or molecules that facilitate biofilm formation or microbial competition through quorum sensing or bioaugmentation to control gross biofilm thickness or microbial composition.
The biofilm thickness can be managed in a drinking water treatment plant, a water reuse plant, a distribution system for drinking water, a collection system for wastewater, a wastewater treatment plant, a plumbing system, a natural or constructed wetland, a storm water treatment system, agricultural buffers, river bank filtration.
The substrate concentration in the bulk or immediate boundary layer of the biofilm can be increased through physical and chemical approaches including but not limited to charge attraction or repulsion, physical or chemical sorption, van der waals forces, proton gradients, channeling for convection such as with activated carbon or extracellular polymeric substances.
The biofilms can be optimized for growth of probiotic organisms for distribution system stability and for improving human health.
Backwash or air scour or surface wash can be applied at multiple levels or heights or depths to provide different solids residence times in a filter or to separately manage or control for effluent turbidity and biofilm mass, volume or thickness.
Another example of the technological solution includes a method for water treatment, wherein a biofiltration process is maintained using single or multiple media surfaces, that are in series, in parallel, or as a tributary, that are used for biofilm retention and a membrane, fabric filter or a blanket clarifier is used for solid-liquid separation, and where the influent to the biofiltration process is subject to chemical treatment using a reactant, oxidant or reductant in a manner that the altered influent material can be further treated if necessary within the biofiltration process.
Another example of the technological solution includes an apparatus for water treatment, wherein a biofiltration reactor is maintained using single or multiple media surfaces, that are in series, in parallel, or as a tributary, that are used for biofilm retention; and a membrane, fabric filter or a clarifier is used for solid-liquid separation, and where the influent to the biofiltration reactor is subject to chemical treatment using a reactant, oxidant or reductant in a manner that the altered influent material can be further treated if necessary within the biofiltration process.
The apparatus can include powdered activated carbon, granular activated carbon, plastic media, ceramic media, sand, anthracite, sponges, rocks, chitin, shells, anthracite, sand, lava rock, glass, expanded clay, green sand, calcified media such as sea shells, synthetic or plastic media, naturally occurring media, other impregnated or encapsulated natural or synthetic or a combination thereof media, media containing special micro or macronutrients such as calcium, magnesium, iron, copper or other metals, phosphorus, sulfur or other inorganics, or, light, heat, magnetic, or electromagnetic or radiation producing media.
PAC or GAC can provide adsorption of organic and inorganic material including but not limited to metals, micropollutants, organic carbon, non-biodegradable or recalcitrant organics.
Polyelectrolytes, inorganic coagulants, flocculants or a combination thereof can be applied for coagulation of incoming particulate and colloidal material as a means of improving effluent quality or maintaining increased membrane permeability and flux, or, providing further support for biofilm growth.
Aeration can be provided for membrane cleaning or also provides for oxygen transfer as an electron acceptor for biofilm growth or modulation or to maintain multiple biofilm oxidation states.
Sparged gas or electron acceptors such as hydrogen, nitrogen, carbon dioxide, argon can be provided for membrane cleaning and control of oxidation-reduction potential and dissolved oxygen concentration.
A physical separator can be included to recover biofilm support media or provide shear to control biofilm thickness and solids residence time, or to maintain and control the biofilm inventory in the reactor.
The physical separator can include a device such as a hydrocyclone, centrifuge or a settler, or a screen, filter, dissolved air floatation and, wherein the physical separator could include an upstream shearing device to modulate biofilm thickness.
The physical separator can provide an inventory that is granular to maintain high membrane permeability and flux and resists membrane fouling.
The media can provide scouring of the membrane filter surface to maintain high membrane permeability and flux and resists membrane fouling.
The membrane could be polymeric, ceramic or made of other inorganic material, cloth, mesh or other fibrous material such as a disc filter.
The membrane could be hollow fiber, flat sheet, flat plate, spiral wound or where the membrane is located in the reactor or in a separate membrane compartment with transfer of solids to and from the membrane tank.
The oxidant can be ozone, chlorine, Ultraviolet, hydrogen peroxide, potassium permanganate, or the combination thereof.
The membrane, filter or clarifier, including a lamella or a solids contact clarifier, can be outfitted with a return pipe to the reactor or coagulation zone.
The terms “a,” “an,” and “the,” as used in this disclosure, means one or more, unless expressly specified otherwise.
The term “biological processor,” as used in this disclosure, means a tank, a vessel, a column, a cylinder, a reactor, or any other structure or device that can contain a liquid, a solid and a water treatment process that can include a biological, chemical or physical mechanism to remove or facilitate removal of constituents from water. A “biological processor” can include, for example, a sequencing batch reactor (SBR), a moving bed biofilm reactor (MBBR), a moving bed biofilm membrane reactor (MBB-MR), a membrane bioreactor (MBR), an activated sludge process (ASP), an up flow anaerobic sludge blanket (UASB) reactor, a granular activated carbon (GAC) filter, a disc filter, a ceramic filter, or any other device or process that can contain or facilitate containment or growth of a biofilm for purposes of removing constituents from water.
The term “constituent,” as used in this disclosure, means any organic contaminant, inorganic contaminant, micropollutant, nanopollutant, organic compound, total organic compound (TOC), inorganic compound, molecule, chemical compound, pesticide, drug, cleaning product, industrial chemical, organism, virus, or any other element or article that can be harmful to an organism or the environment, or any element or article that might not be desirable in water to be used for human consumption or for discharge into the environment, such as, for example, into a stream, a river, a wetland, an ocean, or any other waterway, body of water, or the ground.
The term “constituent concentration,” as used in this disclosure, means an amount of a constituent in a unit of water, such as, for example, but not limited to, an amount of a constituent in moles, μg, or mg of the constituent per-liter of water, or a pH level of the water, or the turbidity level in NTUs (nephelometric turbidity units).
The term “control” and its variations, as used in this disclosure with respect to biofilm(s) or constituent(s), includes, but is not limited to, managing thickness, mass, volume or a composition of a biofilm, or mass or concentration of substrate or an influent constituent (feed forward), effluent constituent (feedback), a constituent within a recycle stream, a constituent within a backwash stream, or a constituent within a waste stream. Control can constitute a manual approach, an automatic approach, or approaches using artificial intelligence or self-learning algorithms.
The terms “including,” “comprising,” “having” and their variations, as used in this disclosure, mean including, but not limited to, unless expressly specified otherwise.
The term “pollutant,” as used in this disclosure, means a micropollutant, a nanopollutant, a total organic compound, or a biodegradable pollutant.
Devices that are in communication with or connected to each other need not be in continuous communication or connection with each other unless expressly specified otherwise. In addition, devices that are in communication or connection with each other may communicate or connect directly or indirectly through one or more intermediaries.
Although process steps or method steps may be described in a sequential or a parallel order, such processes or methods may be configured to work in alternate orders. In other words, any sequence or order of steps that may be described in a sequential order does not necessarily indicate a requirement that the steps be performed in that order; some steps may be performed simultaneously. Similarly, if a sequence or order of steps is described in a parallel (or simultaneous) order, such steps can be performed in a sequential order. The steps of the processes, methods or algorithms described in this specification may be performed in any order practical.
When a single device or article is described, it will be readily apparent that more than one device or article may be used in place of a single device or article. Similarly, where more than one device or article is described, it will be readily apparent that a single device or article may be used in place of the more than one device or article. The functionality or the features of a device may be alternatively embodied by one or more other devices which are not explicitly described as having such functionality or features.
While the disclosure has been described in terms of examples, those skilled in the art will recognize that the disclosure can be practiced with modifications in the spirit and scope of the appended claims. These examples are merely illustrative and are not meant to be an exhaustive list of all possible designs, embodiments, applications, or modifications of the disclosure.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/634,432, titled “Apparatus and Method for Biofilm Polishing in Water Systems,” filed Feb. 23, 2018, which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62634432 | Feb 2018 | US |
