ES2370878B1 - PROCEDURE FOR THE CLEANING OF WASTEWATER THROUGH ECOLOGICAL EQUIPMENT AND COMPACTS. - Google Patents

Abstract

Procedure for wastewater treatment through ecological and compact equipment consisting of a tank with three compartments. The raw water enters the first compartment to perform a pretreatment before its passage to the second compartment where the fine bubble diffusers that provide oxygen to the wastewater are located for what is called the biological treatment of water. The last compartment is a decanter where sludges are to be deposited in the fund that periodically have to be removed by an authorized manager and another part of them will be recirculated again to the first compartment, having an outlet for purified water.

Description

Procedure for the purification of wastewater by means of ecological and compact equipment.

The present invention is based on a wastewater treatment equipment and process by means of emerging aquatic plants in fl owation especially applicable to urban wastewater treatment equipment.

This invention belongs to the technical area of wastewater treatment equipment.

Description of the invention

The present invention consists of a tank with three compartments. The raw water enters the first compartment where it is possible to carry out a pretreatment of the raw water before its passage to the second compartment where the fine bubble diffusers that provide oxygen to the wastewater are located for what is called the biological treatment of the water . The last compartment is a decanter where sludges are to be deposited in the fund that periodically have to be removed by an authorized manager and another part of them will be recirculated again to the first compartment.

State of the art

Oxidation systems allow the degradation of water pollutants by using dissolved air, rich in oxygen. In conventional purification technologies this oxygen is supplied by electromechanical equipment (blowers, turbines, compressors or the like) with the consequent expense of electrical energy, noise and maintenance of these equipment by highly qualified personnel.

The present invention is in line with the P.I. 9700706, W 9800086 ES, W 06000570 ES, P.I. 200502496, W 08000369 ES, W 08000370 ES, P.I. 200101015, P.I. 200900811, P.I. 200901122, P.I. 201030651 and with utility models 201031138 and U201031140.

The present invention aims to simplify the equipment and procedures with the consequent savings.

Advantages of the present invention

The advantages of this invention with respect to the above-mentioned inventions is that with the equipment a significant percentage of oxygen is contributed to the water by means of floating aquatic plants. What entails an important energy saving, elimination of noise, odors and for its maintenance it is only necessary to perform own gardening tasks.

Emerging plants acquire a larger size than floating plants, increasing the diffusion of air from the non-submerged area to the parts of the rhizome that are underwater, so they are more interesting from the point of view of purification. However, in order for them to occupy the surface of the water sheet, they must be provided with a support where they can grow, so despite being emergent, we will force them to float using this support that acts as a float and free all the rhizome area that is found under the sheet of water to favor the diffusion of oxygen from these rhizomes to wastewater.

The present invention provides two embodiments according to the volume of water to be purified.

Description of the designs

To complete the description that has been made and a better understanding of this report, the accompanying drawings that show a preferred, non-limiting embodiment of the object of the invention and in which:

Figure 1 is a vertical section view of a compact urban wastewater treatment equipment designed for a population of one to 12 h-e1.

Figure 2 is a vertical sectional view of a compact urban wastewater treatment equipment designed for a population of 12 to 200 h-e.

Figure 3 is a plan view of the support base for floating plants adaptable to the compact equipment of Figure 1.

Figure 4 is a plan view of two embodiments of the support base for floating plants adaptable to the compact equipment of Figure 2.

1 h-e (equivalent inhabitant), is the biodegradable organic load with a biochemical oxygen demand of five days (BOD5), of 60 grams of oxygen per day.

Preferred embodiment of the invention

Description of a preferred embodiment for compact urban wastewater purification equipment that would consist of a substantially rectangular elongated rectangular tank (1) vertically in the embodiment of smaller size and in the larger horizontally elongated capacity whose side terminations are in the form of hemispheres (A and C). In this embodiment of greater capacity for the first of them enters the discharge (3) of wastewater and on it there is a manhole (2). In the third body (C) in its upper part there is another manhole (2) and the outlet (4) for the purified water.

In the central horizontal body of this embodiment there is a support base (6) that supports emerging aquatic plants (10) holding their rhizomes under water sufficiently aerated. These support bases can have a square, rectangular landscape or round plan and will be formed by HDPE meshes (8) surrounded perimetrically by a PVC pipe or by a hydrotube (7) to which they are joined by means of fixing flanges (9) equidistant.

The blower group (11) will be placed in an area under roof, booth or similar for protection, is connected to a solenoid valve (12) that provides through the tube (5) air and oxygen to the bottom of the central tank where there is a network of air diffusers (13) that provides oxygen to the rhizomes of plants.

The tank is equipped with a venturi tube (14) for the recirculation of wastewater, as well as an inverted U-bent tube (15) whose innermost end has an upward arc and communicates the area A of the tank with B. Zone B communicates with C through a smaller S tube (16).

In the first hemisphere (A) through which the discharge of wastewater enters (3) the separation of solids and fats occurs by decantation, in the central body (B) the aeration and oxygenation of the wastewater occurs and in the second Semi-sphere (C) proceeds to the recirculation of water, the decantation and the discharge of the discharged effluents outwards.

In a second embodiment with lower capacity, the reservoir can have a cylindrical shape with convex lower edges, the center occupying a water plant holder (6 ’).

The deposit has two vertical zones with a cylindrical sector shaped plant (A ’and C’). In the inlet area of the discharge (A ') the separation of oils and grease occurs and is joined by an inverted U-shaped tube that ends at a concave termination and (15') that effects the circulation of water between the two zones (A 'and B'). The equipment consists of a blowing device (11 ’) that injects air into the base of the central tank through two or more diffuser circles (13’) of air. The central deposit (B ’) communicates with the third deposit by a U-shaped tube whose intermediate section has an arcuate shape (16’). In the third tank (C1) there is a submersible pump (17) that recirculates sludge to the first tank (A ’).

In both embodiments, this third zone of the deposit has a sedimentation chamber (C-C) and a discharge outlet (4-4 ’) at its base.

In the embodiment of greater capacity (Figure 2), the tanks located on both sides (AC), are provided with openings with a lid (2) called manhole, the covers are removed and thus the interior of the tank could be accessed in case of having to make any repairs, to observe the characteristics of the wastewater. In both embodiments in the second compartment there is no cover because it is an open compartment above just where we support the plants in fluctuation and in case of having to make repairs or cleaning they are easily removed.

The blower group (11) provides air to the diffusers. It consists of a continuous use membrane compressor without any kind of lubrication or maintenance. It is maintained by inducing an air current for 20-22 hours / day through PVC pipes, D = ½ ”, connected to the diffusers.

The thin bubble membrane diffuser devices (13) are formed by a plastic structure that supports a microperforated rubber membrane with micro-holes that act as a valve: they expand to let the air out, but close once the fl ow has stopped, to prevent water from entering.

They have been widely accepted in wastewater treatment in aerobic processes because of their advantages in terms of oxygen transfer efficiency and energy savings. The membrane diffusers are installed covering the surface of the bottom of the tank, the exact number defined as a function of the amount of oxygen to be transferred.

Debugging procedure

1.-Pretreatment: Degreasing / sanding (first compartment)

Its purpose is the elimination of fats, oils, foams and floating materials lighter than water to avoid interference in subsequent processes. This avoids the overload of the following compartments and the appearance of harmful, harmful organisms in the biological systems.

Degreasing in urban waters is essential and in this case it is carried out in combination with sanding, an alternative that has the following advantages:

The sedimentation velocities of the sands and fluctuation of the fat particles are practically not modified by performing the sanding and degreasing in the same deposit, which is logical if the difference in densities between the particles of sand and fat is considered.

Sand particles, when settling, decelerate the ascending velocities of fat particles. They thus have more time to get in touch with each other during their journey to the surface, increasing the performance of fat flotation.

In the joint system, in the same sandblasting tank (A) a reassuring zone is created where fats accumulate on the surface, being evacuated by surface scanning.

2.-Aerobic biological treatment (second compartment)

Its purpose is the reduction of organic matter present in wastewater once the pretreatment and primary treatment phases have been overcome. The secondary treatment that we propose consists of a biological process carried out by the active sludge procedure.

It consists of a continuous process in which the residual water is stabilized biologically in tanks or activation rafts, in which aerobic conditions are maintained. The effluent, once subjected to the pretreatment process, is sent free of thick solids and fats, to the aeration tank (B) where it receives the oxygen supply necessary for the metabolic action of the microorganisms. This contribution is made through diffusers (13) arranged inside the raft.

3.-Mud accumulation (third compartment)

In a biological treatment of sewage sludge is obtained. One part is recirculated at the beginning of the system to provide the discharge of sufficient organic load and the rest must be evacuated.

4.-Sludge recirculation

The system used for recirculation is the so-called "Venturi System", which takes advantage of the energy of the same air impeller group and aspirates the decanted sludge into the aeration compartment, making the use of other electromechanical elements unnecessary, a circumstance that minimizes both energy expenditure and equipment maintenance itself.

The system is automatic, commanded by a solenoid valve and timer clock.

It consists of a continuous process in which residual water is stabilized biologically in compartment B, in which aerobic conditions are maintained. The effluent of the first compartment passes to a second compartment with an oxygen supply for the metabolic action of the microorganisms that will constitute the active sludge of the treatment plant. This oxygen supply is made through a blower connected to electricity and through diffusers arranged inside the raft.

Claims (4)

1. Procedure for the purification of wastewater by means of ecological and compact equipment, characterized by a substantially rectangular horizontally elongated tank whose lateral terminations are in the form of hemispheres (A and C). In the realization of greater capacity there are at both ends of the tank two manholes with closing lids. In the first department there is an inlet for wastewater and in the last tank there is an outlet for the purified water. In the upper part of the central body there is a base of support that supports emerging aquatic plants holding their rhizomes under water sufficiently aerated. Its support base has a rectangular landscape, being formed by HDPE meshes surrounded perimetrically by a PVC pipe or by a hydrotube to which they are joined by equidistant fixing flanges. In a zone under roof a blowing group connected to an electrovalve is placed that contributes through the tube air and oxygen to the lower part of the central tank where there is a network of air diffusers that contributes oxygen to the rhizomes of the plants. The blower group consists of a continuous use membrane compressor without any kind of greasing. The tank is equipped with venturi-type pipes for the recirculation of wastewater, as well as an inverted U-bent tube whose innermost end has an upward arc and that communicates zone A of the tank with B. Zone B communicates with the C through a smaller S tube. The thin bubble membrane diffuser units are formed by a plastic structure that supports a microperforated rubber membrane with micro holes that act as a valve. 2. Procedure for the purification of wastewater by means of ecological and compact equipment created for a lower capacity, characterized by presenting a cylindrical shape divided in its interior into 3 compartments, the sides with a circular shaped floor plan and the center with a rectangular shape. The first tank through which the water to be purified enters is connected to the central tank by an inverted U-shaped recirculation tube. The equipment consists of a blowing device that injects air into the base of the central tank through two or more air diffuser circles. The central tank (B ’) communicates with the third tank by a U-shaped tube whose intermediate section has an arcuate shape. The third tank has at its base a settling chamber with an inverted U-shaped tube pump and an outlet for the purified water at the top. 3. Procedure for the purification of wastewater, characterized by performing the degreasing combined with the sanding in the first part of the tank creating a calming zone where fats accumulate on the surface. In the central department the aerobic biological treatment is carried out to reduce the organic matter by stabilizing the residual water in the tank with aerobic conditions receiving an oxygen supply to activate the metabolic action of the microorganisms. A part of the accumulated sludge recirculates at the beginning of the system through the venturi system and the rest must be evacuated. SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 201131143 SPAIN Date of submission of the application: 05.07.2011 Priority Date: REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: C02F3 / 32 (2006.01) C02F3 / 20 (2006.01) RELEVANT DOCUMENTS

Category

Documents cited Claims Affected

X

US 2003024874 A1 (WALLACE SCOTT D et al.) 06.02.2003, 1-3

paragraphs [0085-0088], [0091-0092], [139], [141-142]; Figures 3,5,6,17.

X

US 6190553 B1 (LEE SANG EUL) 20.02.2001, 1-3

column 4, line 37 - column 6, line 58; Figures 3-5.

X

US 5618413 A (TODD JOHN H et al.) 08.04.1997, 1-2

column 5, line 3 - column 6, line 11; column 7, lines 28-67; Figures 1,6,7.

X

FR 2833254 A1 (RHIZOS ENGENIERIE) 06.13.2003, 1-2

page 8, lines 3-7; page 9, line 6 - page 10, line 24; figures 1-2.

X

US 5876484 A (RASKIN ILYA et al.) 02.03.1999, 1-2

column 1, lines 30-33; column 8, lines 37-57; column 9, lines 42-58; Figures 1,3,4.

X

US 5156741 A (MORRISON DEAN N et al.) 20.10.1992, 1-2

column 3, line 34 - column 6, line 65; figures 1-2.

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims • for claims no:

Date of realization of the report 25.11.2011

Examiner M. I. Ramos Asensio Page 1/4

REPORT OF THE STATE OF THE TECHNIQUE Application number: 201131143 Minimum documentation sought (classification system followed by classification symbols) C02F Electronic databases consulted during the search (name of the database and, if possible, terms of search used) INVENES, EPODOC State of the Art Report Page 2/4  WRITTEN OPINION Application number: 201131143 Date of Written Opinion: 25.11.2011 Statement

Novelty (Art. 6.1 LP 11/1986)

Claims Claims 1-3 IF NOT

Inventive activity (Art. 8.1 LP11 / 1986)

Claims Claims 1-3 IF NOT

The application is considered to comply with the industrial application requirement. This requirement was evaluated during the formal and technical examination phase of the application (Article 31.2 Law 11/1986).  Opinion Base.- This opinion has been made on the basis of the patent application as published. State of the Art Report Page 3/4  WRITTEN OPINION Application number: 201131143 1. Documents considered.- The documents belonging to the state of the art taken into consideration for the realization of this opinion are listed below.

Document

Publication or Identification Number publication date

D01

US 2003024874 A1 (WALLACE SCOTT D et al.) 06.02.2003

D02

US 5156741 A (MORRISON DEAN N et al.) 20.10.1992

2. Statement motivated according to articles 29.6 and 29.7 of the Regulations for the execution of Law 11/1986, of March 20, on Patents on novelty and inventive activity; quotes and explanations in support of this statement Document D01 discloses a procedure for water purification, which in one of its variants takes place in a compact device (references contained in fig. 17), comprising a solid settling compartment (514), through which the waters to be treated (512), then going to a recirculation chamber (516) from where, once injected with air (546), they are channeled and distributed in a tank with emerging plants (504), to return later to the department of recirculation (475), from where they are evacuated (564). In other embodiments, the oxygen supply is made through tubes (142, fig. 3) or diffusers (164, fig. 6). The invention defined in claim 1 does not differ from the technique described in D01 in any essential way to achieve the same technical effect, which is to contribute to energy saving by providing oxygen to the water by means of aquatic plants. The differences consist of constructive details that do not provide inventive activity, such as the following: the equipment of the invention has two mouths with a lid and that of D01 only one (534, fig. 7); the lateral shape of the tank is hemispherical; it has a central body, on which the plants supported by a mesh are placed; The treated waters are recirculated to the solid separation department and the communication between the departments is done by means of U-shaped and S-shaped tubes. The HDPE (high density polyethylene) type mesh is a known design element of the state of the art, as can be seen in document D02 (col.3, line 58-59). Therefore, claim 1 lacks inventive activity. Claim 2 refers to another embodiment of the invention, whose difference with the previous one consists solely in the shape and size of the equipment, structural features obvious to a person skilled in the art. The sand trap of claim 3 is known from D01 (514, fig. 17) and a person skilled in the art knows that the accumulated fat on its surface is also collected in the decanters. Although it does not indicate in which deposit the sanding / degreasing is performed, it is obvious that it refers to any of those described in the two claimed embodiments, essentially the same except for their capacity. In addition, it is explained in the description. Therefore, claims 1-3 have no inventive activity according to Art. 8 of Patent Law 11/86. State of the Art Report Page 4/4