GB2452828A

GB2452828A - Installation for combusting fats and/or oils of plant and/or animal origin in an i.c. engine

Info

Publication number: GB2452828A
Application number: GB0816253A
Authority: GB
Inventors: Anthony Kerihuel; Luc Gerun; David Guianvarch
Original assignee: S3D SAS
Current assignee: S3D SAS
Priority date: 2007-09-11
Filing date: 2008-09-05
Publication date: 2009-03-18
Anticipated expiration: 2028-09-05
Also published as: BE1018610A3; GB2452828B; ES2368046B1; ES2368046A1; DE202008012127U1; GB0816253D0; FR2920783B1; IT1393659B1; FR2920783A1; ITMI20081602A1

Abstract

The installation comprises a heated chamber 1 for storing in the liquid state the products to be exploited, an internal combustion engine 2 and a heated circuit 3 for circulating the products to be exploited between the storage chamber 1 and the engine 2. The circuit 3 comprising a main intake 4 connected to the storage chamber 1, and at least one auxiliary intake, eg 5,6, for feeding in water and alcohol and/or alcohol derivative. A further auxiliary intake 7 may also be provided for feeding in a surface active agent. The liquids are pumped to a static mixer 26 in the form of a vertically oriented conduit having internal stationary recessed or projecting blades or fins. The static mixer 26 is arranged in series with a collection and dynamic mixing reservoir 8 for the combustible emulsion originating from the static mixer 26, the reservoir 8 comprising a storage tank 9 with at least one moving device 10, eg a rotating bladed shaft, for agitating the contents. The reservoir 8, which is interposed between the outlet of the static mixer 26 and the intake 16 for feeding fuel to the engine 2, forms a buffer volume which is capable of levelling out variations in the fuel consumption of the engine.

Description

Installation for exploitation of fats and/or oils of plant and/or animal origin The present invention relates to an installation for the exploitation of fats and/or oils of plant or animal origin Several industries, in particular the agri-food industries, produce in the course of their activities fats and/or oils of animal or plant origin which qualify as waste which they must dispose of Such is the case, for example, for abattoirs or industrial delicatessens. For a long time this waste or these animal residues were used to manufacture food for the said animals. This practice has now been banned. The fats or oils, known for their capacity for combustion, have led manufacturers to use these products as fuel in boilers. Combustion enables these by-products to be eliminated by producing heat. However, proper combustion requires the addition of troublesome products. Furthermore, the is thermal energy produced by exploiting all the fats of an agri-food manufacturer often exceeds the actual requirements, resulting in dimensioning problems or reselling of the energy. Other industrial routes used are methanization, which exploits the fat waste as combustible gas but does not eliminate its co-products, *c c' since the substrate obtained must subsequently be distributed. Finally, biodigestion is a solution for elimination of fat waste, but does not exploit this waste. If the route of use of fats or oils as fuel, in particular as liquid engine fuel o suitable as a substitute for diesel, has not been widely used, this is in particular * * because the rheological properties (viscosity, pour point etc.) of the fats or oils make their direct use in a diesel engine impossible. In fact, several studies have shown that the combustion of pure animal fat, even of short duration, causes serious fouling of the engine which can lead to it being damaged.

To break free from the poor predispositions of animal fats as a substitute for diesel, a chemical route has been proposed which uses a process for conversion of fats into biodiesel by transesterification of fatty acids. This chemical route, although providing good results, remains very troublesome because of the equipment required, and excludes any possibility of an in situ installation, that is to say on the site where the waste is produced, because of its cost. Physical routes give acceptable results. These physical routes consist of dilution of the fats by a diesel engine fuel fraction and emulsification of the product obtained by an aqueous fraction.

Another technique consists of emulsification of the fats in the presence of water and alcohol These techniques allow a fuel to be obtained without the addition of complex synthetic products and without a complex chemical reaction. To date, production of such a fuel has been developed in the laboratory using complex solutions with the aid of dynamic mixers.

An object of the present invention is therefore to propose an installation of the abovementioned type, the design of which allows both elimination and exploitation, in particular with respect to energy, of the fats and oils to be exploited.

Another aim of the invention is to propose an installation of extremely simple design which allows exploitation in situ, that is to say on the site where the fats and/or oils to be exploited are produced, it being possible for this exploitation to be carried out in-line and continuously. *...

To this effect, the invention provides an installation for exploitation of fats and/or oils of plant and/or animal origin, the said installation comprising at least a * ** chamber for storing in the liquid state the fats and/or oils to be exploited, an internal combustion engine and a circuit for circulating the fats and/or oils to be S..

exploited between the storage chamber and the engine, the said circuit at least comprising, in addition to a main intake for liquid connected to the storage chamber, at least an auxiliary intake for liquid for feeding at least water and alcohol and/or alcohol derivative to the said circuit, at least a mixer fed, by pumping, with liquids originating from the said intakes of the circuit, this mixer, which is capable of forming from the components introduced into the said circuit an emulsion of the water-in-oil type which can be used as a liquid fuel, being arranged in series with at least a collection reservoir for the combustible emulsion, this reservoir, which is interposed between the outlet of the static

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mixer and the intake for feeding fuel to the engine, forming a buffer volume which is capable of levelling out variations in the fuel consumption of the engine, characterized in that the storage chamber and the circuit for circulating the fats and/or oils to be exploited between the storage chamber and the engine are equipped with heating means arranged respectively on the outside of the storage chamber and on the outside of the circuit, in that the mixer, which is arranged upstream of the collection reservoir, is a static mixer which takes the form of a vertically orientated conduit with its intake(s) for feeding with liquid positioned higher than its outlet(s) for discharge of liquid, this conduit being io fitted internally with stationary recessed parts or projecting parts of the type of blades or fins ensuring mixing of the contents of the conduit during their axial displacement inside the said conduit, and in that the collection reservoir is formed from a storage tank for the combustible emulsion fitted internally with at least one moving device for agitation of the contents of the tank.

The use of a static mixer allows an emulsion to be obtained in-line at a lower cost from fats and/or oils circulating in the said installation. * ** * * * * **

The use of a static mixer also allows continuous production of liquid fuel which can be used as engine fuel for an engine integrated into the said installation. S.. *

Furthermore, the presence of a collection reservoir forming a buffer volume and positioned downstream of the static mixer on the circuit for circulating the fats * ** and oils to be exploited between the storage chamber and the engine allows continuous adaptation to variations in the fuel consumption of the engine. In *..

fact, it is known that the engine consumes more or less engine fuel as a function of its load. Due to the presence of the collection reservoir forming a buffer volume, it is possible, regardless of the level of consumption of the engine, to feed the latter in an optimum manner.

According to a preferred embodiment of the invention, the installation is equipped with means which control the functioning of the pump(s) for feeding the liquid to the static mixer according to the filling level of the collection reservoir.

Due to the presence of these control means, the pump(s) for feeding the liquid to the mixer function(s) only if the collection reservoir has not reached its maximum filling level. This arrangement again allows engine fuel to be produced virtually continuously and a possibility of feeding engine fuel to the motor to be ensured under all circumstances, without the risk of overflowing of the said installation.

The invention will be properly understood by reading the following description of embodiment examples with reference to figure 1, which shows in simplified form the elements making up an installation according to the invention.

As mentioned above, the present Invention relates to an installation for the exploitation of fats and/or oils of plant and/or animal origin. Although numerous industrial fields can be envisaged, the invention is more particularly aimed at abattoirs which produce raw fatty co-products, industrial delicatessens which produce cooked fatty co-products and, more generally, any agri-food industry which produces flotation fats. Although the invention is described below more particularly in the case of application to animal fats, the invention can of course be applied analogously to oils of plant origin or to an animal fatlp!ant fat mixture. *.

In the precise case of raw slaughter co-products, melting down, that is to say grinding and cooking of the co-products, is carried out and a triphase separation * * is applied to the said product in order to dissociate the pure fats from the proteins and water present in the waste. Only the pure fats are used in the installation according to the invention.

As regards the cooking fats and the flotation fats, extraction of the fatty fraction can be carried out directly by means of a process which allows a liquid-liquid or liquid-solid separation These fats can thus be animal fats made up of the liquid phase resulting from the liquid-solid separation at elevated temperature of agri-food waste originating from abattoirs. In each case, the aim of prior treatments of these fats is the elimination of the water and solid impurities present in the waste. This prior treatment is necessary especially in the case of waste -.4 originating from abattoirs. Once the fatty fraction of this waste has been obtained, the fats and/or oils to be exploited are stored in a storage chamber 1 and kept in the liquid state in the said chamber. To this effect, the storage chamber 1 is equipped with heating means, such as a resistance, arranged outside the storage chamber 1. These heating means allow a temperature of between 45 and 60 °C to be reached in the said chamber 1.

In addition to the storage chamber 1, the installation also comprises an internal combustion engine 2 and a circuit 3 for circulating the fats and/or oils to be exploited between the storage chamber 1 and the engine 2. This circuit 3 at least comprises, in addition to a main intake 4 for liquid connected to the storage chamber 1 and allowing the fats and/or oils to be exploited to be fed to the circuit 3, at least an auxiliary intake 5 for liquid for feeding at least water and alcohol and/or alcohol derivative to the circuit.

The circuit 3 for circulating the fats and/or oils to be exploited can comprise one or several auxiliary intakes. In fact, it can comprise either one auxiliary intake connected to a source for feeding aqueous liquid containing at least water and an alcohol and/or an alcohol derivative to the circuit, or two auxiliary intakes, 4êS one connected to a source for feeding aqueous liquid, in particular water, to the *. S $ .. : circuit, and another connected to a storage reserve of alcohol or an alcohol derivative. Such is the case in the example shown, where the circuit comprises two auxiliary intakes, one represented by 5 and connected to a source 15A for feeding aqueous liquid, in this instance water, to the circuit, the other *..

represented by 6 and connected to a storage reserve 15B of alcohol and/or an alcohol derivative.

In the examples shown, the circulation circuit 3 also comprises an additional auxiliary intake 7 connected to a reserve 15C of surface-active agent. This additional auxiliary intake 7 of course is not obligatory. It is noted that in the examples shown the circuit is fed first with alcohol, then with surface-active agent and then with water. The alcohol or the alcohol derivative is therefore introduced into the circuit 3 before the water. All the components necessary for the production of an emulsion are introduced into the circuit 3 in liquid form.

Due to the components present, the fuel obtained from the said components can have a composition, expressed by volume with respect to the total volume of the said composition, as follows.

-oils or fats: 68 -90 % -water: 5 15 % -alcohol and/or alcohol derivative: 5 -15 % -surface-active agents: 0 -2 %.

In addition to its main intake and its auxiliary intake(s), the circuit 3 for circulating the fats and/or oils to be exploited between the storage chamber 1 and the engine 2 comprises at least one static mixer 26. This static mixer 26 is fed with liquids originating from the said circuit intakes by pumping. In fact, the installation preferably comprises, for each liquid to be introduced into the circuit 3 for circulating the fats and/or oils to be exploited, a metering pump for delivery of the said liquid into the circuit. Thus, as illustrated in the figure 1, the pump 11 allows the fats and/or oils to be exploited to be delivered into the circuit 3, the *U* pump 12 allows introduction of water into the circuit, the pump 13 allows * .*s introduction of alcohol and/or an alcohol derivative into the circuit and the pump *sSS 14 allows introduction of surface-active agent into the said circuit. * S..

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In a manner characteristic of the invention, the installation is equipped with * ** means 27, 28 which control the functioning of the pump(s) 11, 12, 13, 14 for feeding the liquid to the static mixer 26 according to the filling level of the collection reservoir 8. These pumps generally function in synchronization. This collection reservoir 8, which is arranged in series with the static mixer 26, is interposed between the outlet of the static mixer 26 and the intake 16 for feeding fuel to the engine 2. It therefore allows the formation of a buffer volume upstream of the intake 16 for feeding fuel or engine fuel to the engine such that the engine can be fed in an optimum manner regardless of the load required.

In the examples shown, this collection reservoir 8 is formed by a storage tank 9 for the combustible emulsion fed with fuel by at least one intake 8A connected to the outlet of the static mixer 26. This tank 9 is fitted internally with at least one moving device 10 for agitation of the contents of the tank 9. The reservoir 8 thus forms a dynamic mixer. This moving device 10 is formed here by a rotating shaft with blades. Level sensors, one 28 detecting the minimum filling level of the collection reservoir 8, the other 27 detecting the maximum filling level of the collection reservoir 8, are also arranged inside this collection reservoir 8 These sensors also emit a signal in the direction of a control relay for the pumps 11 to 14 allowing liquids to be fed to the circuit 3 when the level of fuel in the io collection reservoir 8 is lower than the maximum level. These sensors therefore constitute means which control the functioning of the pump(s) for feeding liquid to the static mixer 26 according to the filling level of the collection reservoir 8.

When the collection reservoir 8 is equipped with a moving agitation device, it also acts as a dynamic mixer, completing and reinforcing the action of the static IS mixer 26 for formation of the emulsion.

The advantage of using a static mixer is that it allows in-line production of the emulsion to be achieved. This static mixer 26 takes the form of a conduit fitted internally with stationary recessed parts or projecting parts, of the type of blades or fins, ensuring mixing of the contents of the conduit during its axial displacement inside the said conduit. The conduit constituted by the static mixer 26 is vertically orientated with its intake(s) for feeding with liquid positioned higher than its outlet(s) for discharge of liquid such that circulation of liquid inside the said mixer by gravity is also promoted.

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Preferably, in the example shown, the static mixer used is a known mixer of the : tubular type manufactured by Verder. The use of a static mixer and a dynamic mixer in series allows the formation of a fine homogeneous emulsion. The liquid *:*::* fuel or engine biofuel originating from these stages of mixing is then used for * 30 continuous feeding of the internal combustion engine 2. S. S

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The installation is preferably an installation of the type in which at least a part of the fuel feeding the engine 2, in particular the injection circuit 23 of the engine 2, is returned by means of a suitable pipe 19, called a return pipe. Preferably, the collection reservoir 8 comprises a second intake 8B for feeding with liquid fuel, the said intake 8B being connected to the opening of the return pipe 19 from the s engine which is activated during feeding of the engine with fuel originating from the circuit 3 for circulating the fats and/or oils to be exploited The engine 2 is preferably a hybrid engine functioning alternatively from one or the other of two sources 3, 18 which feed in liquid fuel and can be activated JO selectively, one source 3 of the sources 3, 18 being formed by the circuit 3 for circulating the fats and/or oils to be exploited, and the other by a reserve 18 of fuel oil or diesel.

The reserve 18 of fuel oil or diesel is thus more particularly used during the phase of starting the engine 2, and after production of the liquid fuel based on fats and/or oil to be exploited has stopped. The engine is therefore fed by its reference engine fuel, such as fuel oil or diesel, before and after any use of the liquid fuel obtained from the fats and/or oils to be exploited.

In this particular case, the installation is equipped with a change-over device 17, such as a slide valve, arranged at or close to the intake 16 for feeding fuel to the engine 2, for transfer from one source feeding fuel to another as a function of the desired engine fuel for feeding the engine.

When the installation is of the type in which at least a part of the fuel feeding the engine 2, in particular the injection circuit 23 of the engine 2, is returned by means of a suitable pipe 19, called a return pipe, the installation is preferably equipped with at least two pipes 19, 20 for returning the liquid fuel from the *:*::* engine, which pipes 19, 20 can be activated selectively as a function of the * 30 source activated for feeding fuel. Thus, when the source for feeding fuel is formed by the circuit 3 for circulating the fats and/or oils exploited, return pipe 19 is activated. Conversely, when the reserve 18 of fuel oil is used, return pipe is activated. A change-over device 21, such as a slide valve, allowing transfer from one return pipe to another, is again provided. Preferably, the slide valves 17 and 21 function in synchronization and are controlled from the same control device. It is noted that the change-over device 21 between the two return pipes is positioned between the injection system 23 of the engine and the combustion chamber 22 of the engine 2.

In the particular embodiment of the invention in which at least a part of the fuel feeding the engine 2, in particular the injection circuit 23 of the engine 2, is returned by means of a suitable pipe 19, the opening of which is connected to io the second intake 8b feeding liquid fuel to the collection reservoir 8 when the source feeding fuel formed by the circuit 3 for circulating the fats and/or oils to be exploited is activated, the fuel returned by the engine 2 is reintroduced directly into the collection reservoir 8 forming a buffer volume. This liquid fuel can then be reintroduced at any time into the engine 2 through the intake 16 for is feeding fuel to the engine 2. A closed-loop circuit of at least a part of the engine fuel necessary for functioning of the engine 2 is thus established between the collection reservoir 8 and the engine 2. The collection reservoir 8 therefore has two functions: one consists of serving as a buffer volume allowing the amount of engine biofuel produced to be matched to the effective consumption of the engine, the other of recovery of the engine biofuel returned by the engine when this is not functioning under full load. The engine 2 can then be used for various applications.

In the example shown in figure 1, this engine 2, represented in the form of a **,* 25 block with the aid of dotted lines, is an engine for co-generation combined with at least on the one hand a generator 24 and on the other hand a heat s.

: exchanger 25 for production of electrical and thermal energies. In fact, this engine is connected to an alternator, which converts the mechanical work into electricity. Furthermore, recovery of heat is possible from the gas escaping and from the system for cooling the engine.

The electrical efficiency (ratio between the electrical power produced and the calorific value of the fuel consumed) of the installation is between 25 and 35 %.

The thermal efficiency (ratio between the useful thermal energy produced and the calorific value of the fuel consumed) can reach 45 % if suitable heat exchangers are used It is of course also possible to omit the heat exchangers shown.

The installation is an installation for production of electricity, the engine 2 of which forms one of the elements of an electric generator. This application is preferred.

The process of in-line emulsification of the fats and/or oil uses a static mixer optionally combined with a dynamic mixer The mixing system comprising the static mixer alone or the combination of static mixer and dynamic mixer is designed to reduce the average diameter of the water droplets to below is 100pm. The alcohol or alcohol derivative added to the circuit is preferably a Cl-ClO lower alcohol, preferably a C1-C4 alcohol, such as methanol or ethanol.

Furthermore, the surface-active agent, if present, has an HLB index of less than 10, preferably between 3 and 6.

To avoid any damage to the installation, and in particular any solidification of the fats and/or oils in the circuit 3 of the installation, means for heating the contents of the circuit are provided on at least a part of the circuit 3 for circulating the fats and/or oils to be exploited, the said heating means being arranged outside the circuit 3. These heating means are generally in the form of an electrical resistance or a circuit for circulating hot water, the water having been heated from the heat released by the engine 2. The aim of these heating S...

means is to maintain a temperature of generally between 35 °C and 60 00 inside the circulation circuit 3 and the various elements which make up this *: *::* circuit.

In its basic version, the installation as described above can comprise simply a storage tank 1 for the oils and/or fats to be exploited, a circuit for circulating the fats and/or oils to an engine, with a main intake and an auxiliary intake for ii feeding with liquid, the said liquid being in the form of a mixture containing at least water and alcohol and/or an alcohol derivative, a static mixer and a storage reservoir for fuel originating from the mixer arranged on the said circuit and an engine fed by fuel constituting engine fuel contained in the reservoir 8 forming a buffer volume. An installation of extremely simple design results. * ** * * * * S. * . * * * S.. *** * S * *. S

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Claims

1. Installation for exploitation of fats and/or oils of plant and/or animal origin, the said installation comprising at least a chamber for storing in the liquid state the s fats and/or oils to be exploited, an internal combustion engine (2) and a circuit (3) for circulating the fats and/or oils to be exploited between the storage chamber (1) and the engine (2), the said circuit (3) at least comprising, in addition to a main intake (4) for liquid connected to the storage chamber (1), at least an auxiliary intake (5, 6, 7) for liquid for feeding at least water and alcohol Jo and/or alcohol derivative to the said circuit (3), at least a mixer (26) fed, by pumping, with liquids originating from the said intakes (4, 5, 6, 7) of the circuit, this mixer (26), which is capable of forming from the components introduced into the said circuit (3) an emulsion of the water-in-oil type which can be used as liquid fuel, being arranged in series with at least a collection reservoir (8) for Is the combustible emulsion, this reservoir (8), which is interposed between the outlet of the static mixer (26) and the intake (16) for feeding fuel to the engine (2), forming a buffer volume which is capable of levelling out variations in the fuel consumption of the engine, characterized in that the storage chamber (1) and the circuit (3) for circulating the fats and/or oils to be exploited between the storage chamber (1) and the engine (2) are equipped with heating means arranged respectively on the outside of the storage chamber (1) and on the outside of the circuit (3), in that the mixer (26), which is arranged upstream of the collection reservoir (8), is a *:*::* static mixer which takes the form of a vertically orientated conduit with its

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intake(s) for feeding with liquid positioned higher than its outlet(s) for discharge of liquid, this conduit being fitted internally with stationary recessed parts or .. : projecting parts of the type of blades or fins ensuring mixing of the contents of the conduit during their axial displacement inside the said conduit, and in that *:*::* the collection reservoir (8) is formed from a storage tank (9) for the combustible * 30 emulsion fitted internally with at least one moving device (10) for agitation of the contents of the tank (9).

2. Installation according to claim 1, characterized in that it is equipped with means (27, 28) which control the functioning of the pump(s) (11, 12, 13, 14) for feeding the liquid to the static mixer (26) according to the filling level of the collection reservoir (8)

3 Installation according to one of claims 1 and 2, characterized in that the circuit (3) for circulating the fats and/or oils to be exploited comprises at least two auxiliary intakes, one (5) connected to a source (15A) for feeding the circuit with aqueous liquid, another (6) connected to a storage reserve (15B) of alcohol and/or an alcohol derivatives, and possibly an additional auxiliary intake (7) connected to a reserve (15C) of surface-active agent.

4. Installation according to any of claims 1 to 3, characterized in that the installation comprises, for each liquid to be introduced into the circuit (3) for circulating the fats and/or oils to be exploited, a metering pump for delivery of the said liquid into the circuit, the said pumps (12, 13, 14), the functioning of which is controlled by the filling level of the collection reservoir (8), functioning in synchronization.

5. Installation according to any of claims 1 to 4, characterized in that the collection reservoir (8) comprises a second intake (8B) for feeding with liquid fuel, the said intake (8B) being connected to the opening *:.: of the return pipe (19) from the engine which is activated during feeding of the engine with fuel originating from the circuit (3) for circulating the fats and/or oils to be exploited S.. * . * *. .

6 Installation according to any of claims ito 5, *:*::* characterized in that the engine (2) is a hybrid engine functioning alternatively * 30 from one or the other of two sources (3, 18) which feed liquid fuel and can be *..

activated selectively, one source (3) of the sources (3, 18) being formed by the circuit (3) for circulating the fats and/or oils to be exploited, and the other by a reserve (18) of fuel oil or diesel.

7. Installation according to claim 6, characterized in that it is equipped with a change-over device (17) such as a slide valve, arranged at or close to the intake (16) for feeding fuel to the engine (2), for transfer from one source for feeding fuel to another as a function of the requirements of the engine.

8. Installation according to either of claims 6 or 7, of the type in which at least a part of the fuel feeding the engine (2), in particular the injection circuit (23) of the engine (2), is returned by means of a suitable pipe (19), called a return pipe, io characterized in that it is equipped with at least two pipes (19, 20) for returning the liquid fuel from the engine, which pipes (19, 20) can be activated selectively as a function of the source activated for feeding the fuel.

9. Installation according to any of claims 1 to 8, is characterized in that the said installation is an installation for production of electricity, the engine (2) of which forms one of the elements of an electric generator.

10. Installation according to claim 9, characterized in that the engine (2) of the installation is an engine for co-generation combined with at least on the one hand a generator (24) and on the other hand a heat exchanger (25) for production of electrical and thermal energies. * .* * , * * a. * a -.. * . a * . S S. S a.. * S. * % S * ,a

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