METHOD FOR OPTIMIZING CONSUMPTION OF THE OPERATING RESOURCES OF OZONE GENERATORS

Abstract

The present invention comprises a method for optimizing the consumption of an operating resource of ozone generators in which an oxygen-containing gas is conveyed through an existing gap between two conductors, between which there is a potential difference, wherein the ozone generator has a generator rated power P.sub.n that is achieved when the ozone generator has an electrical power P.sub.el=P.sub.el,max coupled and the oxygen-containing gas is conveyed through the gap with a gas flow φ.sub.N, such that the gas that flows through has an ozone concentration c.sub.ozN, wherein the method comprises the following steps: A) specify a required generator power P.sub.target, B) if 0<P.sub.target<P.sub.n, reduce both the electrical power P.sub.el=P.sub.el,actual<P.sub.el,max and the ozone concentration c.sub.oz,actual<c.sub.ozN, wherein P.sub.el,actual and c.sub.oz is selected in order to achieve the required generator power P.sub.target.

Claims

1. A method for optimizing the consumption of an operating resource of ozone generators in which an oxygen-containing gas is conveyed through an existing gap between two conductors, between which there is a potential difference, wherein the ozone generator has a generator rated power P.sub.n that is achieved when the ozone generator has an electrical power P.sub.el=P.sub.el,max coupled and the oxygen-containing gas is conveyed through the gap with a gas flow φ.sub.N, such that the gas that flows through has an ozone concentration c.sub.ozN, wherein the method comprises the following steps: A) specify a required generator power P.sub.target, B) if 0<P.sub.target<P.sub.n, reduce both the electrical power P.sub.el=P.sub.el,actual<P.sub.el,max and the ozone concentration c.sub.oz,actual<c.sub.ozN, wherein P.sub.el,actual and c.sub.oz is selected in order to achieve the required generator power P.sub.target.

2. The method according to claim 1, wherein P.sub.el,actual and c.sub.oz,actual are selected in such a way that the operating costs of the consumption of the operating resources are reduced in comparison by both a reduction in electrical power with consistent gas flow φ.sub.N,max with an ozone concentration c.sub.ozN and a reduction in gas flow φ.sub.N,actual with consistent ozone concentration c.sub.ozN.

3. The method according to claim 1, wherein a performance map P.sub.oz(P.sub.el, φ.sub.N) is determined for the ozone generator, and according to step A) based on the characteristic performance map a minimum gas flow φ.sub.min and/or a minimum electrical power P.sub.el,min is determined and in step B) φ.sub.actual≥φ.sub.min and/or P.sub.el,actual≥P.sub.el,min is selected.

4. The method according to claim 1, wherein based on the characteristic performance map, multiple combinations of reduced electrical power P.sub.el,actual and reduced ozone concentration c.sub.oz,actual are determined and for each of these combinations, the associated operating costs are determined and in step B) the combination is selected at which the operating costs are the lowest.

5. The method according to claim 3, wherein based on the characteristic performance map, multiple combinations of reduced electrical power P.sub.el,actual and reduced ozone concentration c.sub.oz,actual are determined and for each of these combinations the associated operating costs are determined and an interpolation is made between the determined operating costs and based on the interpolation, a combination is determined, at which the operating costs are minimal, wherein the combination determined in this way is selected in step B).

6. A method according to claim 1, characterized in that in step B), the gas flow is also reduced (φ.sub.N,ACTUAL<φ.sub.N,max).

Description

[0039] Further advantages, characteristics, and possible applications of the present invention will become apparent from the following description of a preferred embodiment and corresponding figures. Here:

[0040] FIG. 1 is a schematic layout of an ozoniser,

[0041] FIG. 2 is an exemplary characteristic performance map,

[0042] FIG. 3 is a graph of the operating costs as a function of the gas flow, and

[0043] FIG. 4 is a comparison of the operating costs.

[0044] FIG. 1 shows a schematic cross-sectional view of an ozoniser 1.

[0045] The ozoniser 1 is constructed as a sandwich structure and comprises a plurality of planar or plate-shaped elements. The first electrode 2 is shown in the middle. High voltage can be applied between this first electrode 2 and the second electrode 3. A first dielectric 5 is arranged between the first electrode 2 and the second electrode 3 and divides the space remaining between the first electrode 2 and the second electrode 3 into the gas channel 7 and the coolant channel 9. An oxygen-containing gas is conveyed through the gas channel 7. Due to the voltage applied between the first electrode 2 and the second electrode 3, an electrical field is formed within the gas channel 7 so that the oxygen molecules can be converted to ozone molecules. However, this produces heat so that the first dielectric 5 heats up. The latter is made of a material having a high thermal conductivity, namely, in the example shown, of ceramic.

[0046] On the side of the first dielectric opposite the gas channel 7, the first coolant channel 9 is arranged. Through it, a coolant, such as water, is channelled through. The coolant channel 9 can be free or filled with a porous material 11 as shown in the example.

[0047] In the shown example, the ozoniser has a substantially mirror-symmetrical construction, i.e., it has a third electrode 4 and a second dielectric 6. The second dielectric 6 is arranged in such a way that it divides the distance between the first electrode 2 and the third electrode 4 into a gas channel 8 and a second coolant channel 10, wherein a second porous material 12, is arranged in the second coolant channel 10. If a voltage is now applied between the first electrode 2 on the one hand and the second and third electrodes 3, 4 on the other hand, and an oxygen-containing gas is conveyed through the two gas channels 7 and 8, ozone is formed therein. The corresponding heat generated is transferred via the two dielectrics 5, 6 into the coolant channel and in the example shown to the porous materials 11 and 12, through which a corresponding coolant flows, in order to dissipate the heat.

[0048] The ozone generator may also be constructed differently. Thus, the use of the porous material is unnecessary. In addition, only one gas channel is needed between two electrodes. The electrodes need not be plate shaped. For example, they could also be cylindrical or hollow cylindrical so that the electrodes can be arranged coaxially to one another and a hollow cylinder shaped gas channel forms between the electrodes.

[0049] The operating costs of such an ozoniser are determined essentially by the consumption of the gas and coolant used, as well as the electrical energy. Depending on the area of application, a variable S.sub.ext in percentage units of the rated power P.sub.n of the system is provided. The desired amount of ozone P.sub.oz,target may be represented by the flow rate φ.sub.N as well as the concentration c.sub.ozN of the ozone-containing gas as follows:

[00001]$P_{\mathrm{azsoil}}=\frac{S_{\mathrm{ext}}}{100}.Math.P_n={\phi }_N.Math.c_{\mathrm{ozN}}\left(P_{\mathrm{si}},{\phi }_N\right)$

[0050] The index N refers to physical standard conditions T.sub.N=273.15 K and P.sub.N=1013.25 hPa. The ozone concentration c.sub.ozN exiting the generator is determined on the one hand by the coupled electrical power P.sub.el and on the other hand by the gas flow φ.sub.N of the product gas. This means that the desired ozone quantity or desired generator power P.sub.oz,target can be determined under otherwise constant external conditions by the parameter combination (P.sub.el, φ.sub.N). At predetermined power P.sub.el and predetermined gas flow φ.sub.N, a corresponding ozone concentration c.sub.ozN is then automatically obtained.

[0051] This means that the electrical power and/or flow rate can be changed to affect the volume of ozone generated. With regard to the operating costs incurred, the two parameters can be varied accordingly.

[0052] Thus, a worse electrical ozone efficiency factor can be accepted if the electrical energy is available at a reasonable price or even free of charge, e.g., due to the presence of a photovoltaic system, if in exchange the gas consumption is lowered.

[0053] The essence of the present invention is the implementation of the system controller in such a way that operating costs are automatically optimized. Thus, in a preferred embodiment it is provided that the operating costs for electrical power and gas used are entered into the controller. This may be done either manually or, in a preferred embodiment, automatically via an interface. In particular, in the case of automated input, the operating costs may be continuously adjusted as a function of external conditions (e.g., the time of day, weather report).

[0054] The operating costs per unit of time for electrical energy and gas are known by

BmkpT=K.sub.el.Math.P.sub.el+K.sub.gas.Math.φ.sub.n

[0055] The parameters K.sub.el and K.sub.gas can be determined based on the current operating costs.

[0056] In order to be able to perform the optimization process, a P.sub.oz(P.sub.el, φ.sub.N) characteristic performance map of the system should be substantially known. In general, a few values are sufficient here in order to create the characteristic performance map by means of extrapolation and interpolation.

[0057] In FIG. 2, a corresponding characteristic performance map is shown, which has been obtained by interpolation and extrapolation. The x-axis represents the gas flow in arbitrary units. The y-axis shows the ozone amount generated in relation to the nominal ozone amount P.sub.n. The individual curves are each included for different electrical powers. The higher the electrical power, the greater the amount of ozone that is generated. The same applies to the gas flow.

[0058] If, for example, an ozone output is to be generated corresponding to 70% of the rated power, a horizontal straight line can be entered at 0.7, as also shown in FIG. 2. This horizontal straight line intersects the highest electrical power characteristic curve at a point that defines the minimum gas flow necessary to produce the desired amount of ozone with the corresponding ozone generation system. The operating costs can now be calculated for all intersection points that this straight line has with the corresponding characteristic curves.

[0059] In FIG. 3, the corresponding operating costs are shown in arbitrary units on the y-axis and the gas flow relative to the nominal gas flow φ.sub.N on the x-axis. The linearity of increasing cost of gas (represented by the squares), the hyperbolically decreasing cost for electrical energy with increasing gas flow (represented by the triangles), and the sum of the gas and energy costs (represented by the circles) are shown.

[0060] Clearly discernible is a minimum of total cost. This minimum can be determined by interpolation. The corresponding value on the x-axis is then the gas flow that should be used to keep the operating costs as low as possible. In addition, interpolation can be omitted. In that case, only the corresponding intersection points are used to calculate the operating costs and then the gas flow is selected which incurs the lowest operating costs.

[0061] FIG. 4 shows for the desired amount of ozone relative to the rated power (x-axis), the operating costs per unit of time in arbitrary units (y-axis) and once for operation at constant gas flow (dashed line) and once at optimized operating means consumption (solid line), as is the subject matter of the present invention. While with the rated power the two curves show identical operating costs, significant costs can be saved with reduced ozone output. These are greater, the smaller the amount of ozone that is requested.

[0062] According to the invention, it is therefore possible to significantly reduce the operating costs of the ozone generator, which in particular improves the operating cost situation considerably when operating many ozone generators.

LIST OF REFERENCE NUMERALS

[0063] 1 Ozoniser [0064] 2 Electrode [0065] 3 Electrode [0066] 4 Electrode [0067] 5 Dielectric [0068] 6 Dielectric [0069] 7 Gas channel [0070] 8 Gas channel [0071] 9 Coolant channel [0072] 10 Coolant channel [0073] 11 Porous material [0074] 12 Porous material