FR2810367A1 - Multiple fuel power station uses synthetic and conventional fuels to supply turbine or thermal engine - Google Patents

Abstract

The multi-fuel power station includes either a gas turbine or a combustion engine running on multiple fuels, powering an alternator to generate electricity from the cheapest fuel available at a particular time. The electric power station comprises at least one dual fuel thermal engine (D). This may be a gas turbine or a combustion engine which is able to be fuelled by one or several fuels (C). These are selected according to price. The output from this turbine or engine is applied to an electrical generator (E), producing a power of between 1 and 10 MW. The fuels used may be synthetic fuels (A) or conventional fuels (B). The synthetic fuels may be formed by a pyrolysis and gasification of industrial or agro-chemical waste. The waste may include old tyres, oils, plastic materials sludge and/or biomass. The conventional fuels may be derived from refining petroleum.

Description

The present invention relates to a supplementary electric power station operating in a bi-fuel system. fuel and its use, especially in decentralized production. Such a plant allows the cogeneration of electrical energy of another energy, for example thermal, chemical or physicochemical energy from conventional fuels and / or fuels.

Currently, in most industrialized countries, most of the electrical energy is produced by three types of power plants, namely traditional coal or oil-fired power plants, hydroelectric power plants and nuclear power plants.

We know all the problems that nuclear power plants can pose in their operational safety first and especially in the problem of radioactive waste disposal.

At the same time, we know the ecological interest that can be represented by natural energies and, more recently, the use of domestic or industrial waste as a source of energy.

There is therefore a compelling need to produce electricity more cleanly and as close as possible to the places of consumption, which amounts to multiplying the places of production by correspondingly decreasing the powers involved.

Hydroelectric booster plants are known which, even if they do not generate polluting derivatives, are, despite everything, decried by the protectors of nature, accused of denaturing the landscapes, and by the fishermen, who see their fishing sites seriously disturbed.

There are also additional gas-fired plants, the combustion of which generates a large amount of energy that can be used in mechanical or electrical form, as well as natural elements, water vapor and carbon dioxide that can be used or recycled. However, adding to the fact that they have low yields, these backup plants have sometimes too high utilization costs, especially during periods when demand for gas is higher are, unfortunately limited to the use of this fuel with fluctuating costs. In fact, it is important to note that electricity demand is often important for winter because of the heating and lighting services that are added to the usual needs related to economic activities. If the demand for electricity is significant during a certain so-called "peak" period, gas demand is parallel increasing and, as a result, the gas less available and more expensive. Nevertheless, there are no consistent rules on energy consumption, and national electricity and gas networks often face imbalances between generation and the need for electricity and gas, depending on the region. dwelling and according to the seasons.

In addition, for security reasons, certain installations and industries can not risk encountering power outages that may be due to, among other things, failures or overloading of the national network.

The present invention aims to solve these problems by proposing a booster power plant comprising at least one energy-efficient twin-fuel thermal machine using, as a primary energy source, renewable and conventional energies. The invention is part of a heat recovery chain that meets the needs of ecological, industrial and domestic. Thus, the power plant according to the invention comprises a dual-fuel thermal machine, the thermal machine consisting of a gas turbine (TAG) or a combustion engine (MAC) that can be powered by one or more combustible fluids liquids and / or gases, and means for converting the energy supplied by the combustion into electrical energy. The fuel (s) are synthetic fuels and / or conventional fuels. Advantageously, the plant according to the invention is capable of co-generating electricity and heat. It is thus used in the cogeneration of electrical, thermal, chemical and / or physicochemical energy.

According to a preferred embodiment, the power plant according to the invention comprises means for recovering the released thermal energy. Advantageously, it comprises means for recovering the carbon dioxide from the exhaust gas and means for converting recovered carbon dioxide for use in the chemical or biochemical industry or in agri-food production. For example, the recovered can be used to feed agricultural crops in greenhouses that require maintaining a sufficient level of CO2 as a carbon source for plants.

The dual-fuel thermal machine may be at least one combustion engine (MAC) or a gas turbine (TAG). The combustion engine (s) may be a gas engine or a diesel engine. The fuels used are in the gaseous or liquid state; some engines even use a liquid gas mixture, the compressed liquid can be used to initiate the combustion of the gas.

The term bi-fuel means that the plant can operate with two types of fuel. The plant thus makes it possible to use fluid fuels, namely conventional liquid and gaseous fuels that are derived from refining or oil extraction; or liquid and gaseous synthesis fuels resulting from the "pyrolysis - gasification" of industrial or agri - food waste. The choice of fuel (s) is made according to their availability and / or price. Different fuels can thus be chosen, particularly according to the seasons or geographical areas. For example, during hot seasons, natural gas is more available and therefore cheaper fuel.

Fuel oil, liquid propane gas (LPG), liquid natural gas (LNG) or natural gas (NG) are examples of conventional fuels.

Used oils, tires, plastics, biomass and sludge are treated by pyrolysis and gasification and thus constitute synthetic fuels as a source of energy for the auxiliary power station, object of the invention.

Advantageously, the plant according to the invention can be used to regulate the national electricity and gas distribution network, notably by enabling the erasing of peak days (EJP). It also makes it possible to secure the installations or industries, in particular by preventing failures of the national network. Thus, the booster plant according to the invention operating in bi-fuel allows to regulate the national gas electricity network and in particular to manage with more flexibility, days of high consumption of gas, fuel and electricity. During these days or periods of "peak", the use of different fuels such as synthetic fuels makes it possible, on the one hand, to provide for energy shortages and, on the other hand, to avoid saturation network that could lead to power cuts to the detriment of consumers.

More particularly, the invention is intended to be installed on sites where the need for electrical energy is greater than normal and to which this energy can hardly be provided by the main power grid, on pain of low profitability or risks to the market. main network. These sites will be primarily urbanized and industrialized sites, precisely where the need for other types of energy, thermal or chemical, is also felt. Such a plant thus allows a decentralized production of energy ranging from 1 to 10 MW and can be considered as an "energy point" located near the installations of source stations of the main electrical network, gas expansion stations brought by gas pipelines. and landfills or industrial or agri-food waste collection sites. It also makes it possible to secure certain installations or industries preventing failures of the national network. The total power delivered during periods of high consumption at the point of use significantly attenuates the phenomena of "micro-cuts" that are detrimental to the quality of the network, particularly in industrial, tertiary or technological areas.

The electrical energy produced by the booster plant according to the invention can be coupled to the main network, and the plant can be equipped with devices for also recovering and in particular the heat energy produced, for example for district heating, since it will be installed where the need arises, ie in urbanized and densely populated areas. In addition, the plant contributes to the elimination of industrial or agro-food waste whose production is also greater in these urbanized areas.

The present invention will be better understood with reference to the accompanying drawings, given by way of non-limiting examples. In these drawings - Figure 1 is a block diagram explaining how to produce heat and electricity from different types of fuels using booster plant according to the invention comprising bi-fuel heat machine.

- Figure 2 is a block diagram explaining how to produce heat and electricity from waste using a booster plant according to the invention and its various uses.

In Figure 1, A and B respectively correspond to synthetic fuels or renewable energies and conventional fuels as defined above. Synthetic fuels A come from a method 1 of "pyrolysis-gasification" detailed in FIG.

The fuel constituting the energy source may be selected from synthetic fuels A or conventional fuels B from refining or oil extraction. The fuel (s) C are selected based on price and availability depending on the time of year and geographical location. They can be in the gaseous state such as natural gas, or the liquid state such as fuel oil or oils.

D is a dual-fuel thermal machine that can be a combustion engine (MAC) or a gas turbine (TAG). engine or the turbine is first of all a high performance tool with a high energy efficiency of about 80%. It is a thermal machine that is clean, economical and extremely reliable and longevity.

The plant according to the invention may comprise a plurality of engines or gas turbines. The air-gas or air-liquid mixture is compressed during the compression stroke of the piston and the ignition of the mixture is achieved by a spark produced by a spark plug or by a pilot injection of a fuel which self-ignites before the top dead center. For engines that use a spark ignition, this can be generated by a low-voltage magneto and contactless electronic switch. A Ruhmhoff type transformer transforms the low voltage pulse into high voltage. One coil per candle and one candle per cylinder is used. The engine or motors of the plant, preferably with a unit power of between 1 and 10 MW, can be connected to an alternator or 60 Hertz / 400 volts. Alternatively, the thermal machine is composed of one of several gas turbines. Electrical energy alternator output E is then raised to the voltage of 20 kV by a three-phase transformer to be delivered to the distribution network G (high voltage service station interconnections and distribution). The thermal machine fed with energy in the form of synthetic fuels A or conventional fuels B, directly supplies the energy electrical transformation to the network G via an alternator E.

The plant according to the invention for the production of electricity delivered to the distribution network G, can be used for combined cycle cogeneration, allowing the supply of a power network, which can be associated with a heat network H or air conditioning using the Carnot cycle. Indeed, the engine or the gas turbine also allows the generation of hot water I and / or domestic or industrial steam J. The heat can be captured by heat exchangers F. Two main sources of heat are the engine water circuit ensuring the removal of heat from the combustion chambers, cylinder head, pistons, etc. and / or the exhaust gas circuit of the engine. It will thus be understood that, by this circuit, it is possible to produce both hot water I for domestic use, pressurized hot water I for industrial use and pressurized steam J for industrial use. The energy thus recovered is essentially thermal or caloric energy.

Advantageously, the exhaust gases of the thermal machine are discharged to a condensing tower X cooled by a primary water circuit at low temperature and at the same time making it possible to recover the latent heat of vaporization of the water vapor contained. in the exhaust gas and at least partially dissolve the CO2 gas. In this way, the carbon dioxide present in the exhaust gas is not released into the atmosphere, which helps to reduce the greenhouse effect.

This CO 2 K recovery may be associated with utilization channels such as, for example, the mineral L chemistry sector with production of CAC03 and Na2CO3 carbonates, which can be used in particular for the acidic earth treatment, the organic L chemistry stream. , with production of heavy CH lines, urea, etc., the biochemistry M or the agri-food sector N. In Figure 2, synthetic fuels are derived from the "pyrolysis-gasification" of industrial waste P or agri-food such as tires, used oils, plastics, biomass or sludge. For this purpose, a known pyrolysis device 2 followed by a device allowing gasification 3 leading to the synthesis of light gases Q and synthetic oils R are used. These latter constitute a source of energy that can be stored or used directly as liquid fuels. or gaseous for supplying the heat engines of the booster plants of the invention. Thus, the plant according to the invention contributes to the elimination of industrial and agro-food waste P. After the pyrolysis step, the residual waste W represents only 3% by weight of the waste P. Another advantage comes from the fact that the gasification step may be followed by a condensation step 4. In fact, 85 to 90% of the gases from the gasification of waste are condensable and provide synthetic oils R, storable liquid fuels that can be burned in the diesel cycle including The non-condensable part, the light gases Q, will be directly used to produce combustion energy in a gas engine.

As explained above, the plant allows the combined decentralized production of heat energy and electrical energy, the cogeneration S. In addition, the possibility of choosing the fuel allows to regulate national electricity distribution network and gas according to the seasons, in particular by allowing the erasing of peak days (EJP) T. The booster plant according to the invention also makes it possible to secure certain installations or industries U, in particular by preventing failures of the national network. The total power delivered during periods of high consumption at the point of use significantly attenuates the phenomena of "micro-cuts" that are detrimental to the quality of the network, particularly in industrial, tertiary or technological areas.

Claims (9)

<B> CLAIMS </ B> 1. Power plant comprising at least one dual-fuel thermal machine, the thermal machine consisting of a gas turbine or a combustion engine that can be powered by one or more fuels and means for transforming the energy supplied. by the combustion of electric energy, characterized in that the fuel or fuels are synthetic fuels and / or conventional fuels. 2. Power station according to claim 1, characterized in that the synthetic fuels are derived from a pyrolysis-gasification process of industrial and / or agro-food waste. 3. Power station according to claim 2, characterized in that the industrial waste and / or agro-food are tires, oils, plastics, sludge and / or biomass. 4. Power station according to claim 1, characterized in that conventional fuels are derived from the extraction or refining of oil. 5. Power station according to claim 4, characterized in that conventional fuels are fuel oil, liquid propane gas, liquid natural gas or natural gas. 6. Power station according to one of the preceding claims, characterized in that it comprises means for recovering the released thermal energy. 7. Power station according to claim 6, characterized in that it comprises means for recovering carbon dioxide from exhaust gas and means for converting the recovered carbon dioxide for use in the chemical, biochemical or food industry . 8. Use of the booster plant according to claims 6 and in the cogeneration of electrical, thermal, chemical and / or physicochemical energy. 9. Use of the booster plant according to claims 6 and in the regulation of the national electricity and gas distribution network, in particular by allowing the erasure of peak days and / or in securing facilities or industries, in particular by preventing failures of the national network.