FR2607490A1 - Biological process for the treatment of vegetable and animal fats using bacteria in purification stations and application of the said process - Google Patents

Abstract

Biological process for the treatment of vegetable and animal fats. The fats to be destroyed arrive via a pipeline 1 from the station scrapers; these fats overflow into a first tank 2 which precedes a second tank 3 and a third tank 4; tanks 2 and 3 comprise oxidation dip-pipes 5 which are fed with compressed air by a compressor unit 6; heating coils 7 are arranged on the walls 8 of tanks 2 and 3; dispensers for bacteria 9 and 10 are arranged at the tanks 2 and 3; a pump is arranged at the bottom of tank 2, tank 3 comprises a pump 12 which draws in the treated water and discharges it towards tank 4, which is used to recover the water thus treated. The invention applies to the treatment of animal and vegetable fats in sewage.

Description

 The subject of the invention is a biological process for the treatment of vegetable and animal fats by bacteria in treatment plants and a device for implementing said process.

 Animal and vegetable fats have always been a problem.

 Currently, the transportation of wastewater to treatment plants follows two separate routes.

1) Sewerage
This flow is helped by several lifting pumps located downstream from the treatment plant. The mains drainage drains all the water, including household and catering grease, not trapped by grease traps.

 Grease frequently remains trapped in lifting stations, blocking floats and hydraulic systems. They are regularly pumped by tanker trucks which clean and empty the grease traps and which discharge the grease thus recovered in treatment plants.

2) The drainers
The emptiers empty the contents of their truck directly to the treatment plant when it is a septic tank. These emptiers empty these greases in the stations which accept them, that is to say unfortunately in withdrawn sewers, thus harming the whole network.

 These fats are indestructible if not by chemical means which considerably affect the proper functioning of treatment plants, biological or physico-chemical.

 On the other hand, these fats can be treated directly by a bacterial process (digestion by bacteria, rejection of water and methane gas). This bacterial process is already used in conventional grease traps (catering, community, large hotels). This process makes it possible to eliminate 90% of the greases, but does not solve the problem of the emptiers who, empty the greases either in station, or in sewers withdrawn by polluting the network.

 The device according to the invention consists in treating fats by a bacterial process at the purification station.

 The device according to the invention consists in treating the fats in successive tanks whose water temperature is maintained between 20 and 400C, by means of heating coils, supplied by an electric boiler to obtain a better yield in the bacterial development. and in the digestion of fats by bacteria, the tanks are oxygenated by oxygenation rods which ensure, on the one hand, the oxygenation of the liquid in said tanks and, on the other hand, the stirring to bring up the fats on the surface where they are digested by bacteria; lifting pumps placed at the bottom of said tanks evacuate the water from the first tank to the second and so on, in cascade, to the last tank which is a settling tank and an analysis tank.

 The attached drawings are given as indicative and non-limiting examples. They represent a preferred embodiment according to the invention. They will allow the invention to be easily understood.

 Figure 1 is a schematic view of the device for implementing the method according to the invention.

 The grease to be destroyed arrives via a line 1 of the station scrapers.

 These greases are poured into a first tank 2, which precedes a second tank 3 and a third tank 4.

 The tanks 2 and 3 include oxygenation rods 5 which are supplied with compressed air by a compressor group 6. This compressed air forms an emulsion which allows the fats to rise or remain on the surface.

 Heating coils 7, supplied by an electric boiler, are arranged on the walls 8 of tanks 2 and 3 in order to maintain the temperature around 20 to 400C which is the ideal temperature for a better yield of bacteria.

 The bacteria may for example be PROLIBAG.G bacteria (trademark registered by SANOSIL).

 Bacteria feeders 9 and 10 are placed at the level of tanks 2 and 3 in order to pour and seed the quantity of bacteria necessary for good biological destruction of fat.

 A suction pump 11 is disposed at the bottom of the tank 2, it sucks the water and delivers it to the tank 3 for a second bacterial treatment which can be milder.

 The tank 3 also includes a pressure suction pump 12 which sucks the treated water and delivers it to the tank 4 which is used to recover the water thus treated, decant it and analyze it to determine the place of final discharge (treatment plant , drainage or discharge into a stream).

 To this end, this last tank 4 can also include a pressure suction pump 13.

Claims (4)

 1. Biological process for the treatment of vegetable and animal fats by bacteria, characterized by the fact  that it consists in treating the waste water by a bacterial process at the purification station and this, in a series of successive tanks where the bacterial action is exerted, the treated water of the first tank (2), being treated then by the second tank (3) and so on until the last tank (4) which is an analysis and settling tank.  2. Method according to claim 1 characterized in that  that the bacteria used are bacteria known for example under the trade mark PROLIBAG.G registered by SANOSIL or the like.  3. Method according to any one of claims 1 or 2 characterized in that  that it consists of treating the greases in successive tanks (2, 3, 4) whose water temperature is maintained between 20 and 400C by means of heating coils (7), supplied by an electric boiler, to obtain the best performance in bacterial development and in the digestion of fats by bacteria, the tanks (2, 3, 4) are oxygenated by oxygenation rods (5) which ensure, on the one hand, the oxygenation of the liquid in said tanks and, on the other hand, stirring to bring up the fat on the surface where they are digested by bacteria; lifting pumps arranged at the bottom of said tanks evacuate the water from the first tank to the second and so on, in cascade, to the last tank (4) which is a settling tank and an analysis tank.  4. Device for implementing the method according to any one of claims 1, 2 or 3 characterized in that  that the grease to be destroyed arrives via a pipe (1) from the station scrapers; these greases are poured into a first tank (2), which precedes a second tank (3) and a third tank (4); the tanks include oxygenation rods (5) which are supplied with compressed air by a compressor unit (6); heating coils (7) are arranged on the walls (8) of the tanks (2 and 3); bacteria feeders (9 and 10) are arranged at the level of the tanks (2 and 3) to discharge and seed the quantity of bacteria required; a pressure suction pump (11) is disposed at the bottom of the tank (2), it sucks the water and delivers it to the tank (3) for a second bacterial treatment which can be milder; the tank (3) also includes a pressure suction pump (12) which sucks the treated water and delivers it to the tank (4) which is used to recover the water thus treated, to decant it and analyze it.