RU2301380C2 - Powerful solar electro-thermal station - Google Patents

Abstract

FIELD: solar radiation engineering.

SUBSTANCE: solar electro-thermal station has motionless spherical mirror concentrator, open-type energy generation air circuit, movable girder rotating around center of sphere and watching Sun's movement, preliminary, basic and water heat exchangers, compressor, turbine and electric generator. Preliminary heat exchanger has cylindrical profile; basic heat exchanger has profile specified by parametric equation. Basic heat exchanger is made of two parts connected in series: lower part, which has profile truncated from the top in correspondence with equation, and top part made in form of truncated cone. Both parts as Preliminary heat exchanger are made in form of longitudinal adjoining separate air ducts having cross-section in form of trapezoid. Preliminary heat exchanger is mounted in air duct between compressor (or regenerative heat exchanger, if any) and basic heat exchanger. Output of basic heat exchanger is connected to input of turbine. Regenerative heat exchanger is mounted at output of turbine. Water heat exchanger is mounted behind regenerative heat exchanger in output airflow coming from turbine. Compressor, regenerative heat exchanger, preliminary heat exchanger, basic heat exchanger, turbine, electric generator and heat exchanger are connected in small-sized energy generating un it disposed in lower and central parts of movable girder.

EFFECT: improved reliability of operation, increased efficiency.

4 dwg

Description

The invention relates to solar engineering, in particular to powerful solar electric heat stations (MSEC).

Known MSETS [1] with a fixed spherical mirror-hub, a movable farm that monitors the Sun, an open air circuit for generating electric and thermal energy, with a main heat exchanger (GTR) for generating electricity and an additional heat exchanger (DTO) for generating electric or thermal energy.

In the specified MSETS, GR has a profile in accordance with the equation

x = cos θ - A cos 2θ- (sinθ) ctg 2θ,

y = A sin 2θ,

where x, y are the coordinates of the points of the GR profile,

l is the distance from the center of the sphere (i.e., the origin) to the top of the GR profile,

θ is the angle between the axis of symmetry of GR directed towards the Sun and the radius of the sphere at the point of incidence of the current ray from the Sun,

x, y, l - are expressed in fractions of the radius of the sphere, taken as a unit.

The same equation defines the profile of the envelope of GR made in the form of a spiral duct.

This equation ensures the perpendicularity of the rays from the mirror at each point in the GR profile.

However, such a general relativity has low efficiency and reliability, because its walls (in particular, in the region of the top of the GTR and the entire spiral-shaped GTR) do not have close enough contact with the purged air-coolant, and there is a high probability of melting of the upper part of the GTR (where the intensity of incoming rays is maximum); as well as the formation of cracks in the body of general relativity due to severe temperature deformations arising from a rapid and uneven temperature drop (heat stroke) at the time of introducing general relativity into the focal region of the mirror, in which the temperature of the blown metal reaches 2000 ° C, while the air temperature at the inlet of the turbine (and at the output of the GTR) should be about 800 ° C.

In addition, the long path of transferring hot air from the GTR to the turbine mounted on top of the support tower or at its base, as well as unused heat from the hot air from the turbine exhaust (with a temperature of about 400 ° C) lead to heat losses and reduce the efficiency of GTR and ITEC as a whole.

The aim of the present invention is to significantly increase the efficiency, reliability and durability of general relativity and MSETS in general.

This goal is achieved by the fact that the proposed Powerful solar electric heat station Geruni - "APEB", containing a motionless mounted mirror collimator made in the form of a hemisphere cutout, an open-type energy production air circuit, a movable farm that watches the Sun, mounted with rotation around the center of the sphere , heat exchangers, compressor, turbine and electric generator, contains RTO, PTO, GTR and GTR, where GTR has a cylindrical working profile, GTR is made of two series-connected parts, neither of the entrance duct with a top-truncated profile, to which the rays come perpendicular to the working surface at each point, and the upper output, made in the form of a truncated cone, both parts made in the form of a series of longitudinal, adjacent to each other individual ducts of trapezoidal section, the PTO is made of of the same air ducts and is installed in the air path between the compressor and the main heat exchanger, the output of which is connected to the turbine inlet, at the outlet of which a PTO is installed, and after it in the exhaust air stream from t Rbin installed the WTO; wherein the compressor, PTO, PTO, VTO, turbine and electric generator are connected to a compact power generation unit located in the lower and middle parts of the mobile farm.

The presence of causal relationships between the totality of the essential features of this invention and the achieved technical result (the purpose of the invention) is primarily as follows.

The new configuration of general relativity (in two parts) and the new design of general relativity (from a number of longitudinal ducts) can dramatically increase its efficiency and avoid the melting of the body of general relativity in the region of the apex, as well as cracks during thermal shock.

The new line-up of PTO, OTO, PTO and BTO together with a compressor, turbine and electric generator into a single power generation unit located in the lower and middle parts of a rotating truss allows to increase the efficiency, reliability and uptime of the MSETS by eliminating heat losses in high-temperature connecting ducts and exclusion of flexible (in two planes) connections of these ducts.

Figure 1 shows the scheme of rays from the Sun in the MSETS system, and the rays are renumbered (0.1, 0.2, ...) in fractions of the radius of the mirror. Figure 2 presents the deformation of general relativity during thermal shock. Figure 3 shows the walls of GR and PTO, made of separate ducts. Figure 4 shows the layout of the main nodes of the power generation circuit MSEC.

From figure 1 it is clear that the density of incoming rays in the region near the top of the profile curve of the former GR (see the dashed line with the vertex at point l) is much higher than at the lower edges of GR. As a result, thermal energy with a power of up to megawatts is collected in the vertex region (i.e., in the quasi-focus of the mirror) and the execution of this region along the dashed line (as in the prototype) will lead to the melting of the GR material. Calculations show that without a jet of air from the compressor (blown between the double walls of GR), the material of GR (steel) will warm up to a temperature of more than 2000 ° C. But this stream of air cools GTR to about 800 ° C. At the same time, the air itself heats up (from the walls) also to about 800 ° C and gives this heat to the turbine, rotating it. This is our goal, but how to get rid of the threat of meltdown?

The problem can be solved by increasing the area (former) of the working surface of general relativity at its top. Figure 1 shows that the upper part of GTR smoothly passes into a truncated cone with a substantially larger (than dashed) surface. In the conical part, the angles of incidence of the rays on the working surface are not straight, i.e. the absorption coefficient is lower, but the reflected part of the energy is directed to the opposite wall of the cone and is absorbed by it. Such multiple reflections from the walls of the cone provide almost complete absorption of energy from each beam. In this sense, the conical part of general relativity can be called a “black body”, from where the rays that got there do not go outside, i.e. give up their heat completely (efficiency is almost 1).

In the lower part of GR, which has a profile in accordance with the above equation, the rays come perpendicular to the working surface at each point, which ensures a high absorption coefficient.

In addition, heat exchangers, in particular GTR and PTO, have the problem of heat stroke when the latter are introduced into the focal region of the mirror. A sharp expansion of the walls of GR and PTO occurs, and their inner walls (working surface) are deformed more and earlier than the outer walls, which warm up to the same temperature later, after a few minutes. But this is enough for cracks to appear in the body of general relativity and technical conditions due to uneven heating. Figure 2 shows the longitudinal deformation of the walls of general relativity during thermal shock. Here it is conditionally accepted that a junction between the upper and lower parts of GR is fixed. The problem can be solved and deformations sharply reduced if the walls are made in the form of longitudinal individual trapezoidal air ducts shown in Fig. 3a. In this case, heat from the working wall to the outer wall of GR will be transferred not only by a stream of air, but also by metal jumpers between the inner and outer walls, which will dramatically accelerate the temperature equalization between the walls. On figb shows a cross section of the ducts and visible jumpers between the walls and a trapezoidal section of the ducts. The introduction of individual air ducts is fruitful in that the walls of general relativity and technical and technical conditions are able to “breathe” during thermal shock, have more flexibility, have the same deformations and do not break.

Figure 4 presents the layout of the entire node power generation. A chain of the following units is presented above GRT: starter (C), compressor (K), turbine (T), regenerative heat exchanger (RTO), water heat exchanger (WTO), electric generator (EG), gearbox (R). The preliminary heat exchanger (PTO) in figure 4 is not shown, because it can be excluded from the system, in the presence of PTO. At the same time, the efficiency of MSEC is increased, since the length of the hot RTO-OTO ducts and the loss of heat in them are reduced.

The upper chain of nodes (C, K, T, PTO) shown in Fig. 4 indicates that its role in the MSEC can be played by an aircraft (or tank) gas turbine engine (GTE) with small alterations: no combustion chambers are needed, it is necessary to provide flanges for air exit from the compressor and its entrance to the turbine. Moreover, many types of gas turbine engines are mounted inside and PTO (as shown in figure 4).

The diagram in FIG. 4 is exaggerated. In fact, the total length of the upper chain is less than the lower diameter of GR, so that the whole chain is included in the cross-sectional dimensions of the movable truss carrying GR.

The operation of the entire system shown in figure 4, is as follows. The starter (C) is turned on from an external power source (e.g., battery) and the compressor (K) drives air through the PTO and GTR, after which the GTR is introduced into the focal region of the mirror, the starter is turned off, and the air heated in the GTR and GTR goes to the turbine ( T) and, giving it heat, rotates it and the generator. In the path of the still hot exhaust air stream from the turbine is a water heat exchanger (WTO), the input of which is supplied with water, which leaves the WTO in hot form or in the form of steam.

MSETS "Arev" is environmentally friendly. She takes air from the atmosphere and returns it without polluting it with combustion products, without burning its oxygen, etc.

MSETS "Arev" can be up to 20 MW each, and this capacity is the same in winter and summer. The efficiency of each powerful station is 0.4-0.5. The cost of electricity generated is about 0.002 am. dollar (0.2) or about 5.6 kopecks per 1 kWh. If it is necessary to have very large capacities, it is more economically feasible to build several MSEC “Arev” of 10-20 MW each.

Literature

1. Geruni P.M. RF patent 2034204, priority 18.08.92, publ. Of. No. 12, 1995

Claims (1)

Geruni-Arev powerful solar electric heat and power station, containing a motionless mounted mirror collimator made in the form of a hemisphere notch, an open-type air circuit for generating energy, a movable farm that monitors the Sun, is mounted for rotation around the center of the sphere, heat exchangers, a compressor, a turbine and an electric generator, characterized in that the electric power station contains regenerative, preliminary, main and water heat exchangers, where the preliminary heat exchanger has a cylindrical working nth profile, the main heat exchanger is made of two series-connected parts, the lower inlet with a profile truncated from above, to which the rays come perpendicular to the working surface at each point, and the upper outlet, made in the form of a truncated cone, both parts made in the form of a series of longitudinal, adjacent to each other individual trapezoidal ducts, the preliminary heat exchanger is made of the same ducts and is installed in the air duct between the compressor and the main heat exchanger, which is connected to the turbine inlet, at the outlet of which a regenerative heat exchanger is installed, and after it, a water heat exchanger is installed in the exhaust air stream from the turbine, while the compressor, regenerative, preliminary, water heat exchangers, a turbine and an electric generator are connected to a compact power generation unit located in the lower and middle parts of the mobile farm.

Images