FR2726546A1 - Descaling and cleaning of drain pipes using bacterial culture - Google Patents

Abstract

Process and device for the descaling and cleaning of water pipes by circulation of a bacterial culture comprise 2 reservoirs (8 and 8') contg. a bacterial culture capable of digesting scale and cleaning pipes, and a suitable nutrient solution. The 2 liqs. are fed (13 and 13') to a mixing vessel (30) where they are diluted in water and mixed (33) at a controlled temp. (9-12, 16). After mixing, the bacterial culture is distributed (32) to the pipes requiring treatment.

Description

DEVICE FOR FILOU CURING DESCALING OF
WASTEWATER PIPES BY CIRCULATION OF A
BACIERIAN CULTURE IN THEIR BREAST, AND METHOD OF IMPLEMENTING
WORK OF SAID DEVICE
The present invention relates to the field of hygiene and quality of life. More particularly, the invention relates to a device for cleaning and / or descaling waste water pipes, in particular building pipes, by circulation of a bacterial culture within them. The invention also relates to a method of implementing said device.

 One of the problems resulting from the growing demand from the public for better hygiene and a better quality of life lies in the scaling of the wastewater networks of apartment buildings, which essentially consist of wastewater collection columns (ci -after called "columns") to which are connected the waste water evacuation pipes from the private parts of the building. When the wastewater networks are scaled up, a toxic gas, sulfurous hydrogen (H2S), is produced. Saturating the air, this gas corrodes the cast iron pipes, dries the PVC conduits and damages the joints. In addition, this gas is also very unpleasant for residents of buildings because it produces a foul odor whose origin is often difficult to locate. The old columns pose in particular real problems to the technical managers in charge of a building , because they become very porous or brittle, with damaged joints. Traditional methods of cleaning and / or descaling, such as the use of high-capacity hydrocure vehicles (in particular tankers) to carry out the treatment at the foot of the columns or directly on the sewage pipes, is generally not not sufficient and may cause water damage. In addition, the pipes of the private parts which had previously been abandoned, reach a fouling rate which limits the effectiveness of the treatment of the column.

 The drawbacks and shortcomings mentioned above are resolved by the present invention, which provides a device and a method for cleaning and / or descaling wastewater networks by circulation of an activated bacterial culture within it, which allows to process the entire said network without being obliged to intervene on each of its pipes.

The device according to the invention comprises:
- At least two tanks containing one, an aqueous solution of bacterial strains capable of ensuring said cleaning and / or descaling and the other, an aqueous solution of a nutrient suitable for the development of said bacterial strains;
- Means for transferring said solutions of bacterial strains and nutrients to a conditioning chamber;
a conditioning chamber in which the bacterial culture is carried out by seeding an appropriate volume of water with said aqueous solution of bacterial strains contained in one of the reservoirs and said aqueous solution of the nutrient contained in the other reservoir;
- Means for mixing the bacterial culture in said conditioning chamber;
- means for controlling and regulating the temperature in the conditioning chamber;
- Means for the distribution of the bacterial culture contained in the tank in the pipes to be cleaned and / or descaled.

The bacterial strains which are suitable for the purposes of the invention are all the bacterial strains, well known to those skilled in the art, capable of degrading and / or decomposing the organic materials from the effluents of the wastewater networks. These strains must be non-pathogenic and conform to the nomes
AFNOR NFX 42070 and NFX 42000 concerning safety. The specific strains of the triacylgiycerol cycle are particularly suitable for the purposes of the invention.

 These strains and their nutrients are generally commercially available in lyophilized form.

 To perform the cleaning and / or descaling according to the invention, it is therefore necessary firstly to "wake up" the strains and to rehydrate the nutrients. These operations are carried out in the tanks into which the lyophilized strains and nutrients are introduced respectively with water at a temperature of between 25 and 30 ° C. In general, 5 liters of water are used for 750 g of lyophilized powder of bacteria and / or nutrient.

 The bacterial culture is then carried out in the conditioning chamber by seeding an appropriate volume of water using the solutions contained in the two reservoirs; these solutions being brought into the tank by appropriate transfer means, such as pipes fitted with pumps or other devices allowing the contents of the tanks to be emptied into the packaging chamber.

 The amounts of bacterial solution and nutrient solution to be used depend on the amount of water to be seeded. For example, it will be indicated that 5 liters of each solution (bacterial and nutrient) can be used to seed 250 to 300 liters of water in the conditioning chamber.

 The water thus sown is then stirred and maintained at a temperature of the order of 25 to 30 ° C. for a time sufficient to allow the development of the bacterial strains until an effective bacterial culture is obtained. The term effective bacterial culture designates an aqueous suspension containing 108 to 1016 bacteria / ml. In general, this time called "conditioning time" is of the order of approximately 12 hours. The mixing of the seeded water is ensured by any suitable mixing means to increase the contact surfaces of the water with the air contained in the conditioning chamber.

It is possible, for example, to use agitators of different types, such as paddle agitators.

 According to a preferred variant of the invention, the transfer and stirring means can be combined as illustrated in FIG. 1 below.

 The bacterial culture obtained is then distributed in the wastewater network to be treated by appropriate distribution means, operating under conditions which do not alter the activity of the bacterial culture and which are adapted to ensure an adequate flow rate thereof. this.

The invention will now be described in more detail with reference to the accompanying drawings in which:
- FIG. 1 is an embodiment of the device according to the invention;
- FIG. 2 is a representation of the waste water discharge column of a building being treated.

The device according to the invention shown in FIG. 1 includes:
- two tanks (8) and (8 ');
- a conditioning chamber (30);
- combined transfer and mixing means, consisting of:
* a main pipe (33) on which is mounted a pump (4) and possibly a valve (5), said pipe (33) being arranged so as to take the water sown in the lower part of the conditioning chamber and recycling it in the upper part of said chamber;
* secondary pipes (13, 13 ') coming from the tanks (8, 8') and opening out via the venturis (6,6 ') in said main pipe (33) to bring there, in a controlled manner, respectively the bacterial solution and the nutrient solution, said lines (13, 13 ') each further comprising a valve (7, T);
The end of the column (33) in the lower part of the conditioning chamber is advantageously provided with a strainer (3) and the end (331) of the column (33) in the upper part is provided with perforations. Thus during the recycling of the water taken from the lower part of the conditioning chamber, it is diffused into the chamber in fine jets, which makes it possible to increase the contact surfaces of the water with the air.

The conditioning chamber (30) also includes:
a water inlet pipe (1), the end of which is situated in the chamber (30) is advantageously provided with a strainer (2) and
- A drain pipe (34) on which is mounted a valve (13), said pipe (34) being advantageously provided at its end with a strainer (14).

 The conditioning chamber (30) may also include means for controlling the level of liquid, consisting for example of a transparent tube (28) situated outside said chamber which connects the lower part and the upper part of the chamber and a ball (27) which indicates by the system of communicating vessels the level of liquid.

The means for controlling and regulating the temperature in the conditioning chamber can be constituted respectively:
- temperature measurement probes (10) and (11), one of them being connected to a recorder (16), the other to a control panel (9);
- an ambient temperature measurement probe (15), also connected to the recorder (16), the data recorded by the recorder (16) being transmitted to the control panel (9) by conventional means not shown on the face;
- a heating resistor (12) which is automatically put into operation according to the temperatures recorded so that the temperature inside the chamber (30) is maintained at an appropriate constant value, preferably approximately 30 ° C., to promote development bacterial strains.

 The device according to the invention also comprises a pipe (32) which constitutes, with the connection pipes (20, 22), the means for distributing the bacterial culture in the wastewater network to be treated. One end of the pipe (32), provided with a strainer (17) is located in the lower part of the conditioning chamber and the other end is connected to the connection pipes (20, 22).

 On the pipe (32) is mounted a pump (18) having suitable characteristics to allow the distribution, at a flow rate of the order of 10 Vmin, of the bacterial culture of the conditioning chamber of the device of the invention located at foot of a building, for example in a vehicle, to the top of that without altering the activity of said culture. The pump (18) is advantageously a vane pump. Advantageously, this type of pump makes it possible to obtain a flow rate of the bacterial culture in the column to be cleaned and / or descaled in the order of 10 Vmn at 50 m high without creating point pressures greater than 10 bars.

The implementation of the device of the invention consists in:
1 / introduce a given quantity of water into the conditioning chamber (30) via the pipe (1);
V inoculate this water with the bacterial solution contained in one of the reservoirs (8, 8 ') and the nutrient solution contained in the other reservoir (8, 8') by starting the pump (4) and opening the valves (5, 7, 7 ');
3 / stir the water thus sown for a sufficient time to obtain an effective bacterial culture, for example by taking the water from the bottom of the tank through the pipe (33) and by recycling it in the upper part of said chamber while maintaining the temperature inside the chamber (30) at around 30 ° C .;
4 / when the bacterial culture has reached its desired degree of efficiency, stop the pump (4) and distribute said culture in the wastewater network to be cleaned and / or descaled after connection of the pipe (32) to the pipes connection (20, 22) and operation of the pump (18) and opening of the valves (19, 21).

 Advantageously, a nozzle (25) is fixed to the end of the connection means (22) making it possible to diffuse the bacterial culture in the column for discharging the wastewater (24) of a building (23) and the taps of the pipes for removing waste water from the private parts (26) of the building.

 The device and method according to the invention are very advantageous compared to conventional devices and methods since they allow in particular to clean and / or descale the waste water pipes of a building without having to intervene at the foot of the column or in private apartments. They also offer the advantage of considerably limiting the risks of water damage, major inconvenience of conventional cleaning and scaling.

 In addition, the device and method according to the invention represents an undeniable economic advantage: the bacterial strains stopping the emanation of H2S and consuming the fatty sediments (or softening them in the worst case) contained in the pipes, it is now it is possible that old cast iron pipes over 20 or 30 years old that have never been cleaned and which have become porous by oxidation, recover their initial flow capacity. This procedure is carried out without risk of water damage and at very much lower costs than those generated by an outright replacement of these pipes, or by the passage of a water-purifying vehicle working at a pressure of 300 bars which would explode the joints and would disembowel, under pressure, the majority of the portions to be cleaned.

Claims (5)

 1. Device for cleaning and / or descaling wastewater pipes by circulation of a bacterial culture within them, characterized in that it comprises:  - at least two reservoirs (8, 8 ') containing one, an aqueous solution of bacterial strains capable of ensuring said cleaning and / or descaling and the other, an aqueous solution of a nutrient suitable for the development of said strains bacterial;  - Means for the transfer (13,13 ') of said solutions of bacterial strains and of nutrient towards a conditioning chamber;  - A conditioning chamber (30) in which the bacterial culture is carried out by seeding an appropriate volume of water with said aqueous solution of bacterial strains contained in one of the reservoirs and said aqueous solution of the nutrient contained in the other tank;;  - Means for mixing (33) the bacterial culture in said conditioning chamber;  - means for controlling and regulating the temperature in the conditioning chamber (9, 10, 11, 12, 16);  - Means for the distribution (32, 20, 22) of the bacterial culture contained in the chamber (30) in the pipes to be cleaned and / or descaled.  2. Device according to claim 1, characterized in that the transfer and stirring means are combined and made up:  * a main pipe (33) on which is mounted a pump (4) and possibly a valve (5), said pipe (33) being arranged so as to take the water sown in the lower part of the conditioning chamber and recycling it in the upper part of said chamber;  * secondary pipes (13, 13 ') coming from the tanks (8, 8') and opening out via the venturis (6,6 ') in said main pipe (33) to bring there, in a controlled manner, respectively the bacterial solution and the nutrient solution, said lines (13, 13 ') each further comprising a valve (7, 7');  3. Device according to one of claims 1 or 2, characterized in that the containment chamber (30) further comprises:  a water inlet pipe (1), the end of which is situated in the chamber (30) is advantageously provided with a strainer (2) and  - A drain pipe (34) on which is mounted a valve (13), said pipe (34) being advantageously provided at its end with a strainer (14).  4. Device according to any one of claims 1 to 3, characterized in that the means for controlling and regulating the temperature consist of:  - temperature measurement probes (10) and (11) in the conditioning chamber (30),  - an ambient temperature measurement probe (15);  - a heating means (12), the probes (10) and (11) being connected, one to the recorder (16), the other to a control panel (9), the control panel (9) and the recorder (16) being connected.  5. Method for cleaning and / or descaling waste water pipes by using the device according to any one of claims 1 to 4, characterized in that it consists in:  1 / introduce a given quantity of water into the conditioning chamber (30) via the pipe (1);  V inoculate this water with the bacterial solution contained in one of the reservoirs (8, 8 ') and the nutrient solution contained in the other reservoir (8, 8') by starting the pump (4) and opening the valves (5, 7, 7 '); ;  3 / stir the water thus sown for a sufficient time to obtain an effective bacterial culture, for example by taking the water from the bottom of the tank through the pipe (33) and by recycling it in the upper part of said chamber while maintaining the temperature inside the chamber (30) at about 30- C;  4 / when the bacterial culture has reached its desired degree of efficiency, stop the pump (4) and distribute said culture in the wastewater network to be cleaned and / or descaled after connection of the pipe (32) to the pipes connection (20, 22) and operation of the pump (18) and opening of the valves (19, 21).