WO2012000693A1

WO2012000693A1 - A method, an apparatus and a method to install the apparatus for biological treatment of water

Info

Publication number: WO2012000693A1
Application number: PCT/EP2011/055112
Authority: WO
Inventors: Anal Chavan; Vrajesh Mehta
Original assignee: Siemens Aktiengesellschaft
Priority date: 2010-06-28
Filing date: 2011-04-01
Publication date: 2012-01-05

Abstract

A method for biological treatment of water including providing an inlet (1) for water inflow, providing an outlet (2) for water outflow, providing a water flow-path (3) comprising a surface (4) adapted to deposit and culture a bio-film (5) of micro-organisms from plurality of micro-organism types, depositing and culturing the bio-film (5) of micro-organisms, wherein the micro-organism types are adapted to be in symbiotic relationship with each other, the water flow-path (3) is adapted to receive water from the inlet (1) and transmit water to the outlet (2), and the bio-film (5) is adapted to treat the water flowing through the water flow-path (3). Prior to treating water, a biological water treatment apparatus (11) having the inlet (1), the outlet (2), the water flow-path (3) and the surface (4) to deposit the bio-film (5) is installed and then the bio-film (5) is deposited and cultured. The bio-film (5) deposited on the surface (4) includes a first layer (6) of the algae and the second layer (7) of the bacteria.

Description

A method, an apparatus and a method to install the apparatus for biological treatment of water.

Biological treatment of water is a process of removing contaminants from water by using micro-organisms through microbial metabolic activities, so as to reduce chemical oxygen demand (COD) and/or biochemical oxygen demand (BOD) of water. COD is a test to measure amount of oxygen required by organic compounds in water, which can be oxidized by

chemicals, while BOD is a test to measure amount of

biodegradable organic matter in the water. BOD is performed under strictly specified conditions and procedures and slight deviations may result in substantial errors. Also, BOD is more time consuming.

To make the testing process fast, easy and accurate, COD is used. Commonly used COD removal techniques are conventional activated sludge process (ASP) , ASP with extended aeration and membrane bioreactor (MBR) , which are based on degradation of organic matter using bacterial cultures. For this purpose, bacterial cultures require oxygen for the degradation of organic matter, which is supplied by provision of aeration systems. The operation of this aeration system is associated with huge power consumption resulting in high operation cost.

One way to reduce operational cost due to aeration is

suggested by the US Pat. No. 6596171, wherein ASP is provided with aeration and re-aeration zone, so that the air once entered into the process can be re-used. But, still the operational cost is high, as still the power consumption cannot be substantially reduced. It is an object of the invention to biologically treat the water in a cost-effective way.

The object of the invention is achieved by a method for biological treatment of water according to claim 1, a method for installing a biological water treatment apparatus according to claim 9 and the biological water treatment apparatus according to claim 10. The underlying idea of the invention is to treat water biologically by flowing the water through a water flow-path having a surface with a bio-film of various micro-organisms having symbiotic relationship with each other. Due to the symbiotic relationship between the micro-organism types, the requirement for aeration is fulfilled by the micro-organism type which releases oxygen while generating energy for its growth and sustenance. This helps to make the water treatment system self-sustainable for aeration requirement, thus reducing the operation cost for running the water treatment system. This also helps to make the system less complex and easy to handle due to self-sustainable aeration within the apparatus .

According to one embodiment, the micro-organism types are algae and bacteria, so that, oxygen produced by algae is consumed by bacteria. Such a system provides for sustainable growth of both algae and bacteria, as algae and bacteria has good symbiosis for each other growth. Also, algal surface acts as a substratum for the growth of bacteria, which in turn increases the retention time of the biofilm over the surface of the water flow-path, which in turn enhances the treatment efficiency of the system. According to an exemplary of the invention, the bio-film comprises multiple layers of micro-organisms, so that, each layer of micro-organism is having distinct micro-organism types. This helps to provide for systematic culturing and maintenance of the cultured bio-film.

According to yet another embodiment, the bio-film comprises of a first layer of algae and a second layer of bacteria, wherein the first layer adapted to be deposited on the surface of the water flow-path and the second layer is adapted to be deposited on the first layer. This helps to systematically place the algae and bacteria as a bio-film, so that when oxygen is generated by the algae, it is

systematically absorbed by the layer of bacteria which is directly in contact with the layer of algae, thus helping for healthy and fast culturing of the bacteria, which in turn enhances the removal of organics from water.

According to another embodiment, a light source is provided for photosynthesis by micro-organisms to culture the micro^¬ organisms. This helps to provide an additional lightning source beyond natural light or room light reaching the micro^¬ organism, so that, the micro-organisms can receive required amount of light for proper photosynthesis, hence healthy culturing of micro-organisms.

According to yet another embodiment, the light source is an arrangement of LEDs placed over a body and the body placed above the water flow-path, so that the bio-film is exposed to the light. This helps to provide lighting uniformly to the micro-organisms for proper distribution of light among micro^¬ organisms, so that, each part of the bio-film can be cultured efficiently . According to an exemplary embodiment, an opening is provided for allowing a waste gas produced by micro-organisms while treating the water to flow out of the apparatus. This helps to prevent dissolution of the waste gas into the water being treated.

According to one embodiment, the apparatus for the biological water treatment has a processing tray comprising a pattern of walls making a water flow-path. Such an apparatus provides additional surface for depositing and culturing of micro^¬ organisms due to the heights of the walls.

According to another embodiment, the pattern of walls

comprises of a plurality of wall arranged in a fashion to make the water flow-path having zig-zag geometry. This helps to optimize the size of apparatus by utilizing maximum space for providing the water flow-path.

According to yet another embodiment, the pattern of walls comprises of two walls arranged in a fashion to make the water flow-path having spiral geometry. This helps to provide smooth water flow-path for swift and laminar flow of water.

According to one embodiment, the apparatus includes a

plurality of the processing trays, wherein the processing trays are detachably interconnected to each other

sequentially to make the water flow-path. As the processing trays are detachably arranged, so the system can easily assembled and dismantled or the capacity can be decreased or reduced by increasing and decreasing number of the processing trays in the apparatus. This also makes monitoring of the apparatus easily, as while any problem in apparatus,

particular trays can be easily identified where the problem occurs . The above-mentioned and other features of the invention will now be addressed with reference to the drawings of a

preferred embodiment for the present method and apparatus for biological water treatment. The illustrated embodiment of the method and apparatus for biological water treatment is intended to illustrate, but not limit the invention. The drawings contain the following figures, in which like numbers refers to like parts, throughout the description and

drawings.

FIG 1 illustrates a lateral view of an apparatus for

treatment of water having a processing tray with a pattern of walls arranged in a fashion to make a water flow-path having zig-zag geometry.

FIG 2 illustrates a lateral view of the apparatus with the processing tray and a body having an arrangement of LEDs placed over the processing tray.

FIG 3 illustrates a dissected front view of the apparatus having two layers of algae and bacteria deposited on the surface of water flow-path. FIG 4 illustrates a front view of the apparatus having a plurality of processing trays.

FIG 1 shows an apparatus 11 for biological treatment of water having an inlet 1 for water inflow, an outlet 2 for water outflow, a water flow-path 3 comprising a surface 4 for depositing and culture a bio-film 5 of micro-organisms from plurality of micro-organism types, and the bio-film 5, arranged in such a way that the water flow-path 3 is adapted to receive water from the inlet 1 and transmit water to the outlet 2 and the bio-film 5 is adapted to treat the water flowing through the water flow-path 3.

The micro-organism types can be classified as aerobic and anaerobic types. The micro-organism types can also be further classified by there cellular structure as prokaryotes like bacteria, etc and eukaryotes like algae, fungi, etc.

The micro-organism types are in symbiotic relationship with each other, so that, each of the micro-organism types can grow sustainably and support each other during culturing.

For cleaning the water, firstly, the apparatus 11 is

installed. During installation, the bio-film 5 is deposited and cultured for some time before starting process for water treatment. When the bio-film 5 is cultured to a required level, the water treatment starts by flowing water from the inlet 1 and after treatment the water is flown out from the outlet 2. According to an exemplary embodiment, the bio-film 5 is deposited in a multiple layer format, where each layer represents different micro-organism types. In such a case, while installation, the layer deposited over the surface 4 of water flow-path 3 is deposited and cultured first and then each subsequent layer of micro-organism is deposited and cultured separately over prior layer to make the bio-film 5 of micro-organism sustainable and healthy for water

treatment. Yet alternatively, the bio-film 5 can be installed in a way to create a pattern of parts of bio-film 5, where the parts of the bio-film 5 represent different type of micro-organisms in a random or a regular repeated pattern. The water flow-path 3 provides a continuous flow of water from the inlet 1 to the outlet 2. The water flow-path 3 has the surface 4 on which the bio-film 5 is deposited. The surface 4 for bio-film 5 deposition is continuous for regular treatment and continuous treatment of water. Alternatively, the surface 4 for deposition of the bio-film 5 can be

discontinuous with a regular or irregular inter-leaving pattern of space. Yet alternatively, the space for deposition can be of some regular denting, so that, the micro-organism are deposited on the dented part to allow proper culturing of the bio-film 5 or for treatment of water to remove the COD and BOD optimally. The apparatus 11 includes a processing tray 12 having a pattern of walls 13 to make the water flow-path 3. The pattern of walls 13 is arranged in a way to make the water flow-path having zig-zag geometry. Also, the pattern of walls 13 is in a way to provide continuity in flow of water. The arrangement of walls 13 is made to provide maximum volume flow of water through the water flow-path 3. According to an alternative embodiment, the arrangement of walls 13 should be in a way to optimize the surface 4 for bio-film 5 requirement and the volume of flow of water through the water flow-path 3. Yet alternatively, the pattern of walls 13 has two walls 13 arranged in a way to make the water flow-path having spiral geometry, so that the flow of water through the water flow-path 3 is smooth and laminar without turbulence and disturbance .

In an exemplified embodiment, the apparatus 11 need not include the processing tray 12 having water flow-path 3, rather the apparatus 11 can include a pipe having the water flow-path 3 or any such structure sufficient to provide a water flow-path 3.

In one exemplary embodiment, an aeration source can be provided regularly or on certain time intervals as required by the culturing of micro-organisms. The aeration can be provided as a concentrated flow of oxygen by using an oxygen source or providing natural flow/ pressurized flow of air through the water flow-path 3 or by mixing oxygen/air in water flowing into the water flow-path 3 through the inlet 1 or by providing an opening 10 for air to flow naturally inside the apparatus 11 or any such way to provide aeration to the micro-organism to be absorbed by micro-organisms for culturing of micro-organisms. Flow of water through the water flow-path 3 can be regulated using a mechanical mechanism of valves like ball-check valves, control valves, gate valves, shut-off valves, etc or an automated mechanism to control the flow of water into the apparatus 11 on a basis of various factors like level of COD, over flow of water, quality of water, efficiency of bio-film 5 to treat water, quantity of clean water required, or any such factors which can be quantified to control flow of water . The apparatus also helps to remove ammonia due to higher pH of water under treatment, as culturing of algae and presence of algae or because of the consumption of ammonia by algal culture removes ammonia from the water. Moreover, this system does not convert ammonia to nitrate, which needs further treatment.

FIG 2 illustrates the apparatus 11 according to one of an exemplary embodiment, wherein the apparatus 11 is having the processing tray 12 and a body 9 with an arrangement of LEDs 8 placed over the processing tray 12. The LEDs 8 are uniformly placed in such a way that the micro-organisms of the bio-film 5 are receiving light uniformly and equally. The LEDs 8 are arranged in such a fashion that the arrangement is

complementary to the water flow-path 3 and makes a zig-zag arrangement in complement to zig-zag water flow-path 3. The light from LEDs 8 is used by micro-organisms for undergoing photosynthesis while culturing and functioning of the bio- film 5. Alternatively, the bio-film 5 need not receive light from the uniform arrangement of LEDs 8, rather the LEDs 8 can be randomly arranged on the body 9 to provide light non- uniformly. Yet alternatively, the light source need not be LEDs 8, rather the light source 8 can be a single sodium lamp or any other generally used electrified light source 8 placed in centre of the body 9 or in any part of the body 9 to provide light optimally to the micro-organisms of the bio- film 5. Still alternatively, the light source 8 need not be placed on the body 9, rather light source 8 can be embedded inside the surface 4 of the water flow-path 3 or the surface 4 of the water flow-path 3 can itself function as the light source 8 or light source 8 can be hung over the water flow- path 3 to provide light uniformly and optimally to the micro^¬ organisms of the bio-film 5. According to one exemplary embodiment, the body 9 having the LEDs arrangement 8 is such that it is placed on the water flow-path 3 and not the whole of the processing tray 12.

However, it will illuminate the whole surface of the tray 12 to provide uniform illumination for the growth of bio-film 5.

The body 9 is placed over the processing tray 12 in a way to provide a gap between the processing tray 12 and the body 9 for providing an access to flow out waste gases generated by the micro-organisms while treating the water. In one

embodiment, the body 9 with the opening 10 can be placed tightly over the processing tray 12, so that the waste gas can escape from the opening 10 on the body 9. In an

alternative embodiment, the body 9 can be placed tightly over the processing tray 12 with the opening 10, so that the waste gas can escape from the opening 10 on the processing tray 12.

Exemplarily, the apparatus 11 having bio-film 5 with two layers of algae and bacteria deposited on the surface 4 of water flow-path 3 is shown in FIG 3. The first layer 6 of the bio-film 5 includes algae and the second layer 6 of the bio- film 5 includes the bacteria. While installing the apparatus 11, firstly, the first layer 6 of algae is deposited over the surface 4 of the water flow- path 3 and subsequently, after culturing of the first layer 6 for some time, the second layer 6 of the bacteria is

deposited over the first layer 6. The first layer 6 is in symbiotic relationship with the second layer 6, as bacteria and algae are symbiotic to each other. The algae produces oxygen while undergoing photosynthesis and the oxygen

produced is utilized by the bacteria for culturing of

bacteria. While, bacteria during culturing produces carbon- di-oxide which can be utilized by the algae while

photosynthesis. Thus first layer 6 and second layer 6

supports each other to grow and function properly.

The second layer 6 of bacteria is deposited over the first layer 6 of algae, in a way that the bacteria get stuck on pores of algae. Such depositing facilitates proper absorption of oxygen by the bacteria, as when algae produces oxygen, the bacteria absorbs oxygen from pores of algae directly. This further helps to facilitate healthy culturing of bacteria without any external source of aeration.

In one exemplary embodiment, the first layer can be of bacteria and the second layer can be of algae, so that, while installation, firstly the first layer of the bacteria is deposited and cultured by providing a aeration source for culturing the bacteria, subsequently, the second layer of algae is deposited and cultured. In this case, when the second layer of algae is cultured to a level to provide sufficient oxygen to bacteria for bacterial growth, the aeration source can be removed to make the water treatment self-sustainable for aeration.

In one alternate embodiment, there can be alternate layers of algae and bacteria placed as the bio-film 5 over the surface 4 of the water flow-path 3. While installing, each of the layer is deposited one on another certain interval of time required for growth of each of the layer. This time interval can be different for each of the layer depending on the culturing needs of each of the layer. For optimal culturing of bacteria, additional aeration source can also be provided for certain time interval as required by culturing of a layer of bacteria. The apparatus according to FIG 3 also helps to remove ammonia due to higher pH of water under treatment, as culturing of algae and presence of algae or because of the consumption of ammonia by algal culture removes ammonia from the water. Referring to FIG 4, an embodiment is exemplified, wherein the apparatus 11 is having a plurality 14 of processing trays 12. According to the illustrated embodiment, the processing trays 12are interconnected and placed on one another, in such a way that the inlet 1 of the apparatus 11 is providing water to a processing tray 12 placed on top and the outlet 2 of the apparatus 11 is providing exit to the water after treatment from a bottom most processing tray 12 amongst the plurality of processing trays 12. The processing trays 12 are

interconnected in a way to make water flow-path 3 continuous, so that water enters into the top-most processing tray 12, then enters into a second tray 12 from the top, then subsequently to processing trays 12 which are consecutively placed one below another, and finally to the bottom most processing tray 12 to exit through the outlet 2 of the apparatus 11.

Claims

What is claimed is: 1. A method for biological treatment of water comprising:

- providing an inlet (1) for water inflow,

- providing an outlet (2) for water outflow,

- providing a water flow-path (3) comprising a surface (4) adapted to deposit and culture a bio-film (5) of micro- organisms from plurality of micro-organism types,

- depositing and culturing the bio-film (5) of microorganisms ,

wherein the micro-organism types are adapted to be in symbiotic relationship with each other, the water flow-path (3) is adapted to receive water from the inlet (1) and transmit water to the outlet (2), and the bio-film (5) is adapted to treat the water flowing through the water flow- path (3) .

2. The method according to the claims 1, wherein the micro^¬ organism types are algae and bacteria, so that, oxygen produced by algae is consumed by bacteria.

3. The method according to any of the claims 1 or 2, wherein the bio-film (3) comprises multiple layers (6, 7) of micro^¬ organisms, so that, each layer (6, 7) of micro-organism is having distinct micro-organism types.

4. The method according to the claim 3, wherein the bio-film comprises of a first layer of algae (6) and a second layer

(7) of bacteria, wherein the first layer (6) adapted to be deposited on the surface (4) of the water flow-path (3) and the second layer (7) is adapted to be deposited on the first layer ( 6) .

5. The method according to any of the claims from 1 to 4, comprising :

- providing light from a light source (8) for photosynthesis by micro-organisms to culture the micro-organisms.

6. The method according to claim 5, wherein providing the light uniformly by an arrangement of LEDs (8) adapted to be uniformly placed on a body (9),

wherein the body (9) is adapted to be placed above the water flow-path (3) , so that the bio-film (5) is exposed to the light .

7. The method according to any of the claims from 1 to 6, wherein the micro-organisms are adapted to produce a waste gas while treating the water, the method further comprising:

- providing an opening (10) for allowing the waste gas to flow out to an atmosphere.

8. A method for installing a biological water treatment apparatus (11) comprising:

- providing a biological water treatment apparatus (11) comprising an inlet (1) for water inflow, an outlet (2) for water outflow, a water flow-path (3) having a surface (4) adapted to deposit and culture a bio-film (5) of micro^¬ organisms from plurality of micro-organism types,

- depositing and culturing the bio-film (5) of microorganisms ,

wherein the micro-organisms of one types provide surface for depositing and culturing of micro-organisms of other types, the micro-organisms of different types are adapted to be in symbiotic relationship with each other, the water flow-path (3) is adapted to receive water from the inlet (1) and transmit water to the outlet (2), and the bio-film (5) is adapted to treat the water flowing through the water flow- path (3) .

9. A biological water treatment apparatus (11) comprising: - an inlet (1) for water inflow,

- an outlet (2) for water outflow,

- a water flow-path (3) comprising a surface (4) adapted to deposit and culture a bio-film (5) of micro-organisms from plurality of micro-organism types,

wherein the micro-organism types are adapted to be in

symbiotic relationship with each other and one , the water flow-path (3) is adapted to receive water from the inlet (1) and transmit water to the outlet (2), and the bio-film (5) is adapted to treat the water flowing through the water flow- path (5) .

10. The apparatus (11) according to claim 9 comprising:

- a processing tray (12) comprising a pattern of walls (13) making the water flow-path (5) .

11. The apparatus (11) according to claim 10, wherein the pattern of walls (13) comprises of a plurality of walls (13) arranged in a fashion to make the water flow-path (5) having zig-zag geometry.

12. The apparatus (11) according to claim 10, wherein the pattern of walls (13) comprises of two walls (13) arranged in a fashion to make the water flow-path (5) having spiral geometry .

13. The apparatus (11) according to any of the claims 9 to 12, comprising: - a plurality (14) of the processing trays (12), wherein the processing trays (12) are detachably interconnected to each other sequentially to make the water flow-path (5) .

14. The apparatus (11) according to any of the claims from 9 to 13, wherein the micro-organism types comprise of algae and bacteria .

15. The apparatus (11) according to any of the claims from 9 to 14, wherein the bio-film (5) comprises multiple layers (6,

7) of micro-organisms, so that, each layer (6, 7) of micro^¬ organism is having distinct micro-organism types.

16. The apparatus (11) according to any of the claims 15, wherein the bio-film (5) comprises of a first layer (6) of algae and a second layer (7) of bacteria, wherein the first layer (6) adapted to be deposited on the surface (4) of the water flow-path (3) and the second layer (7) is adapted to be deposited on the first layer (6) .

17. The apparatus (11) according to any of the claims from 9 to 16, comprising:

- a light source (8) adapted to provide light for

photosynthesis by micro-organisms to culture the micro- organisms.

18. The biological water treatment apparatus according to claim 17, wherein the light source (8) is an arrangement of LEDs (8) adapted to be uniformly placed on a body (9) to provide uniform lighting for photosynthesis of micro-organism to culture the micro-organisms,

19. The apparatus (11) according to claim 18, wherein the micro-organisms are adapted to produce a waste gas while treating the water and the body (9) is adapted to be placed above the water flow-path (3) , so that to provide an opening (10) between the body (9) and the water flow-path (3) for allowing the waste gas to flow out of the apparatus (11) .

20. The apparatus (11) according to any of the claims from 9 to 19, comprising:

- an aeration source adapted to stimulate culturing of the micro-organisms .