A BIOTECHNOLOGICAL METHOD FOR THE REGENERATION OF HYDROCARBONS FROM DREGS AND MUDS, ON THE BASE OF BIOSURFACTANTS

Abstract: A biotechnological method for the regeneration of hydrocarbons from dregs and muds, comprising the use of special products belonging to the class of biosurfactants of the kind of control, sophorolipid, rhamnolipid, trehalose-6.6' dimycolate, cellobiose lipid, belonging to the class of surfactant or surface-active agents of natural origin of the extra-cellular kind of the class called ramnolipids, and the relative process for industrial production, with the following phases: -fluidification, -addition, -emulsifying, of the hydrocarbons and circulation, -separation of the phases or desemulsifying, -final cleaning.

Description: A BIOTECHNOLOGICAL METHOD FOR THE REGENERATION OF HYDROCARBONS FROM DREGS AND MUDS, ON THE BASE OF BIOSURFACTANTS The present invention concerns a biotechnological method for the regeneration of hydrocarbons from dregs and muds, based on the use of compounds class known as biosurfactants. It is well known that the accumulation of sediments on the bottom of storage tanks for crude oil/fuel is a great problem for the oil companies. The dregs mainly consist of particles of heavy paraffin, water and inorganic residues precipitated from the crude oil/fuel during the storage. The accumulation of sediments on the bottom of the dosing tanks causes different problems: - a reduced storage capacity; - contamination of the stored oil with water, particles of heavy paraffin and inorganic residues; - obstruction of the water drainage pipes with consequent problems of accumulation and corrosion; - possible obstruction of the oil extraction pipes; - the sediment rises and the roof can not lower to the resting position. For the oil companies, the cleaning of the storage tanks for crude oil fuel of great dimensions is a difficult and expensive operation. Until now, the manual removal of the muds has been the safest method for assuring the efficiency of the cleaning of storage tanks of great dimensions. However, the manual cleaning shows many disadvantages, like: - the tanks must stay standing for the whole cleaning; - an important contamination of the surrounding area, dangerous for the personnel and for the equipment of the refinery; - a great number of hands are needed; - the removed mud can not be used and the quantity of regenerated hydrocarbons is very low; - high discharging costs for dregs and muds are very high. It is the aim of the present invention to realize a method for the regeneration of hydrocarbons under elimination of all above mentioned disadvantages. The aim set forth is reached by means of the method for the regeneration of hydrocarbons from dregs and muds according to the present invention that comprises the use for special products belonging to the compound class known as biosurfactants, and the process for realizing the same. Said compounds are of the kind of control, sophorolipid, rhamnolipid, trehalose-6.6' dimycolate, cellobiose lipid, belonging to the class of surfactant or surface-active agents of natural origin of the extra-cellular kind of the class called ramnolipids, with the chemical name of RLL or Rl (α-L-ramnopiranosil-α-L-ramnopiranosil-β-hydroxidecanoil-β- hydroxidecanoate) RRLL o R2 (2-O- -L-ramnopiranosil-α-L- ramnopiranosil-β-hydroxidecanoil-β-hydroxidecanoate), and the production whereof occurs by means of an aerobic fermentation in a rigorously controlled conditions, making use of a bacteria branch called pseudomonas aeruginosa, without any bacterium and biodegradable in short time, thus having a very low environmental impact at a very low toxicity. The physical features show that they may be used as emulsifying and surface-active agents. In a number of applications, they have shown a greater efficiency than conventional surfactants or surface-active agents, with the same concentration. Following to the method according to the present invention, the product consisting of biosurfactants, water and the carrying hydrocarbon is introduced in the muds or dregs by shaking the content of the tanks by means of recirculation pumps and adjustable nozzles. The demolition of mud banks is influenced by a combination of water, carrying hydrocarbon and biosurfactant, with the energy supplied inside the tank. After a period of suitable recirculation and a constant monitoring by means of test in loco and in laboratory, the shaking will be interrupted. The content of the tank will be now divided into three phases consisting of layers of regenerated hydrocarbons, water and residual sediments, nearly all consisting of inorganic material. The two products - oil and water - are separately removed according to their destinations. Now an aesthetical cleaning operation is performed, using conventional manual methods, and this operation proves to be easy due to the minimum residual remaining (usually about 5% to 10% of the original muds); this means that the time used and the labour employed in this part of cleaning are reduced to a minimum and the intervention may be finished under safe conditions. In a possible variant, the process according to the present invention may be described as follows: - fluidification: - the hydrocarbons determined for the partial fluidification are introduced, - a first fluidification shaking is performed, with the eventual help of biosurfactants, for the predetermined time period; - addition: - water mixed with biosurfactants is injected (through recirculation and/or mixing tanks, and nozzles), using the fireproof net as a retrieval source, or other sources; - emulsifying of the hydrcarbons and circulation: - the recirculation is performed for the predetermined time period; through the pumps, sampling takes place in the morning and during the night and the water quantity is regulated so as to obtain the correct relationship for regenerating the hydrocarbons, - the water level, determined through sounding or a water revealing paste, is interrupted for 24 hours or for as long as it has been predetermined, - crude oil or gas-oil is added and mixed, for a predetermined time period on a simulation basis and following to laboratory tests and to the worked out data, using the tools for the treatment of the tank (interface sucking between hydrocarbon and water phase; - separation of the phases or desemulsifying: - for a time period of at least 24 hours (or for a predetermined time period and/or for a period determined in the treatment phase), the separation process takes place, or until the complete separation is obtained and the hydrocarbons are transferred into a tank of appropriate dimensions, - the interface is transferred into a tank of appropriate dimension, eventually passing through API-separators, and the water (after a COD-test and an oil-content test) is led to a depuration or discharge section; - final cleaning phase: - the final cleaning takes place, if necessary wit h conventional methods.

Claims: CLAIMS 1. A biotechnological method for the regeneration of hydrocarbons from dregs and muds, characterized in the use of special products belonging to the class of compounds called biosurfactants, of the kind of control, sophorolipid, rhamnolipid, trehalose-6.6' dimycolate, cellobiose lipid, belonging to the class of surfactant or surface-active agents of natural origin of the extra-cellular kind of the class called ramnolipids, and the production whereof occurs by means of an aerobic fermentation in a rigorously controlled conditions, making use of a bacteria branch called pseudomonas aeruginosa, without any bacterium and biodegradable in short time, thus having a very low environmental impact at a very low toxicity. 2. A method according to claim 1, characterized in the following industrial process: - the product consisting of biosurfactants, water and the carrying hydrocarbon is introduced in the muds or dregs by shaking the content of the tanks by means of recirculation pumps and adjustable nozzles; - after a period of suitable recirculation and a constant monitoring by means of laboratory tests, the shaking will be interrupted and the content of the tank will be divided into three phases consisting of layers of regenerated hydrocarbons, water and residual sediments from which the hydrocarbons present since the beginning are extracted and regenerated; - oil and water are separately removed according to their respective destinations; - a cleaning operation is performed. 3. A method according to claim 1, characterized in that the process comprises the following phases: - fluidification: - the hydrocarbons determined for the fluidification are introduced, - a first fluidification shaking is performed, with the eventual help of biosurfactants, for the predetermined time period; - addition: - water mixed with biosurfactants is injected (through recirculation and/or mixing tanks, and nozzles); - emulsifying of the hydrcarbons and circulation: - the recirculation is performed for the predetermined time period; through the pumps, sampling takes place in the morning and during the night and the water quantity is regulated so as to obtain the correct relationship for regenerating the hydrocarbons, - the water level, determined through sounding or a water revealing paste, is interrupted for 24 hours or for as long as it has been predetermined, - crude oil or gas-oil is added and mixed, for a predetermined time period on a simulation basis and following to laboratory tests and to the worked out data, using the tools for the treatment of the tank (interface sucking between hydrocarbon and water phase; - separation of the phases or desemulsifying: - for a time period of at least 24 hours (or for a predetermined time period and/or for a period determined in the treatment phase), the separation process takes place, or until the complete separation is obtained and the hydrocarbons are transferred into a tank of appropriate dimensions, - the interface is transferred into a tank of appropriate dimension, eventually passing through API-separators, and the water (after a COD-test and an oil-content test) is led to a depuration or discharge section; - final cleaning. 4. A method according to claim 1, characterized in the following ramnolipids: RLL or Rl (α-L-ramnopiranosil-α-L-ramnopiranosil-β- hydroxidecanoil-β-hydroxidecanoate) RRLL or R2 (2-O-α-L- ramnopiranosil-α-L-ramnopiranosil-β-hydroxidecanoil-β- hydroxidecanoate).

Inventors: PESCE LUCIANO, PESCE, LUCIANO
Applicants: IDRABEL ITALIA S R L, JENEIL BIOSURFACTANT COMPANY L, IDRABEL ITALIA S.R.L., JENEIL BIOSURFACTANT COMPANY, LLC
Application year: 2001
Main classification: B08B9
IPC codes: B01D17, B01F17, B08B9