FI125067B - Combined cooling, heating and electricity generation plant - Google Patents

Description

TECHNICAL FIELD The present invention relates to refrigeration, heating and power generation, without a compressor. It deals with a combined central cooling and power plant consisting of a water tank, where the water is boiled at the vacuum pressure produced by the ejector, whereby the reduction in the required energy level in the water causes it to freeze. For example, salt is added to the ice, whereby the liquid ice formed is transferred to heat exchangers, which cool the air, refrigerators, freezers and freezers etc. The melting water of the ice is transferred back to the tank. The steam required by the ejector is produced in a steam boiler. The steam released from the ejector is transferred to a steam turbine which, when combined with a generator, produces electricity.

State of the art

Globally, a great deal of energy is used for cooling, because of course the thermal energy is always cooler. With global warming, more energy needs to be spent on cooling.

Conventional electrically driven compressor cooling is energy-intensive and has a high electrical connection power requirement. Its efficiency is at its best when the temperature difference between indoor and outdoor is minimal, ie when cooling is the least needed. Under extreme conditions, the efficiency of COP is known to be 1. Compressor cooling utilizes the phase change energies of the medium in the evaporator and condenser, but when it is heated by the compressor, it is immediately cooled in the condenser, so efficiency is not optimal. Absorption cooling utilizes e.g. waste heat is energy efficient. Based on the Seebeck phenomenon, the thermoelectronic unit converts heat into electricity, but is expensive to produce, making it unsuitable for applications requiring higher amounts of energy.

Compressor cooling is the main cause of power outages in warm areas. Compressor-cooled condensers, on the other hand, intensify the abundant warming of urban areas. Urban Island Effect.

In addition to air cooling, the compressor is used for cooling refrigerators, refrigerators and sinks. For example, in a large store, the heat generated by the compressors heats the interior, which needs to be electrically cooled. The efficiency of electricity production is about 40%. Combined heat and power (CHP) production is about 30% and heat production efficiency is about 60%, ie CHPs total about 90%, which reduces energy consumption by about 25% compared to separate production. The CHP plant may include a steam turbine combined with a generator. Electricity is also needed for lighting, technical equipment, etc.

The standards govern the use of refrigerants as follows: CFCs, fully halogenated chlorofluorocarbons, eg R11, R12, R502, which are prohibited in new refrigeration equipment as well as in its maintenance. HCFCs, hydrochlorofluorocarbons, eg R22, are prohibited for use in new refrigeration equipment and refrigeration with the exception of recycled refrigerant. HFCs, hydrofluorocarbons, e.g.

R1 34a, R404A, R407C, R410A and R413A, these materials may be used in both new equipment and maintenance. HCs, hydrocarbons such as propane and butane, are good and efficient refrigerants, but unfortunately combustible. For more than a decade, all household refrigerators and freezers have had isobutane as a refrigerant. Natural refrigerants, e.g. ammonia and carbon dioxide; ammonia is a powerful refrigerant, but toxic and (poorly) combustible, carbon dioxide operating pressures are high.

ODPs also aim to control their use as follows: ODP = Ozone Depletion Potential (R-11 = 1.0) describes its ozone depletion potential relative to the worst refrigerant R11. GWP = Global Warming Potential (C02 = 1.0), its ratio is 1, which describes the effect of one kilogram of carbon dioxide on the greenhouse effect over a hundred years. The GWP of the invention is 0.0.

It is known that liquid water begins to boil if its vapor pressure is higher than the ambient air pressure, regardless of temperature. Evaporation of water requires 540 calories per gram. In a vacuum, this energy is drawn from the liquid water until the water freezes. In this process, latent heat is utilized as the state of the water changes from a liquid to a vapor and is still solid.

The vacuum can be obtained by a vacuum pump, which normally uses electricity, or by an ejector, which is a steam flow suction pump.

District cooling is recommended if it can utilize already existing piping used for eg district heating.

Purpose of the Invention

If electricity is produced, it is worth producing as CHP, as a cogeneration of heat and electricity, but in warmer regions the crucial question is: What is the use of thermal energy? It is an object of the invention to provide the energy required for cooling with waste or other carbon-based materials so that the electricity produced is used for purposes other than cooling.

The ejector is, at its simplest, two nested tubes, of which the inner, shorter tube tapers evenly towards the end; the outer tube has a separate suction tube on the side.

When, for example, water or steam is added to the combination, the flow rate increases; it follows that it tends to absorb the air in the outer tube and create a vacuum in the tube. And because the suction tube is located on the side of the outer tube, a suction effect depends on the flow rate. Ejectors are used, for example, in laboratories when dehumidification of a test unit is required.

The object of the invention is to provide a combined cooling, heating and power generating plant which, without a compressor, evaporator or condenser, acts as a cooling device, refrigerator, cold sink, freezer, snow and ice maker, desalinator, heater and power generator.

Latent or latent heat is not detectable as heat, but is the energy required to change the state of the material, eg from ice to water and from water to steam. These state changes can be endothermic or energy-binding or exothermic. For example, the energy needed to evaporate water is released when the steam condenses back into water.

There is enough water in the world and it is inexpensive and environmentally friendly compared to, for example, conventional heat transfer agents. As is well known, water phase transition energies, when properly utilized, offer significant advantages.

The invention utilizes a number of transformational energies of water states. The temperature around the container containing the Kim fluid drops, at some point the pressure of the saturated vapor corresponding to the temperature is equal to the pressure of the vapor in the air. This is the Dew Point. The water begins to condense or condense while releasing the energy needed for evaporation. Evaporation is the reverse reaction to this. The invention provides a dew point, condensation release and evaporation binding energy are utilized optimally.

Further, the invention utilizes boiling and freezing of liquid water as follows. The specific heat of evaporation of water at normal pressure is about 2260 kJ / kg, which is equivalent to 40.8 kJ / mol. This is about five times the amount of energy needed to heat the water from 0 ° C to 100 ° C. Condensation, or condensation, is the counterproductive process of evaporation, which, due to the loss of energy, releases the same amount of energy as when evaporated. In the pursuit of high energy efficiency, it would make sense to make the most of these state-of-the-art energies, namely latent heat.

Freezing water at overpressure is known, but due to high pressure it is not cost effective, at least not in air conditioning.

The difference between boiling water and evaporation is that in boiling steam is also generated inside the water and not just on its surface. The boiling point of water decreases as the external pressure decreases, this is called vacuum distillation.

When the water vapor pressure is equal to or greater than the external pressure, evaporation also occurs inside the water, gas bubbles are formed and the water boils. Evaporation intensifies as the surface of the liquid is no longer blocked. If the differential pressure is maintained, the entire fluid will boil. Boiling needs energy, it is taken from the liquid water until all the energy is utilized, and the state of the liquid water changes to a lower level, whereby the water is in solid form, that is, in ice.

Example of partial pressure of saturated water vapor: If the room temperature is 21 ° C and the relative humidity is 37% and the dew point is 5,6 ° C.

The partial pressure of saturated water vapor at 5 ° C is 8.72 mbar and at 6 ° C it is 9.35 mbar. Since this pressure is almost directly proportional to the temperature, an interpolation of f = p / p max x 100% gives a partial pressure of 9.10 mbar. At 21 ° C, the maximum pressure pmax = 24.9 mbar, respectively, at 0 ° C is 6.1; 20 ° C 23; 23 ° C 28; 25 ° C 32; 30 ° C 42.4; 40 ° C at 74 and 50 ° C at 123 mbar. The specific heat of melting ice is 333kJ / kg. As hot air is directed through a tank containing ice, the air temperature drops, while the ice begins to melt.

Liquid ice is a crystallized form of water, is highly fluid and easy to transport by piping.

The invention is characterized in that the water-tight sealed container is connected, for example, by a tube to the ejector. When it draws in air from the tank, a vacuum builds up, whereupon the water in the tank begins to boil, and when the energy required for it is taken from the water, it freezes.

The vacuum required in the invention is not achieved by vacuum pumps using electricity or otherwise by electricity, but by the ejector, the steam required for which is produced, for example, by burning a gas produced by a heating plant utilizing waste or carbon-based materials. The steam is used as electricity in a steam turbine, which is connected to an electric generator, the electricity from which is used in electric motors required by the plant, such as pumps. The waste heat from the steam turbine is utilized for preheating the incineration or gasification plant. The rest of the electricity is used for eg lighting and electronic equipment, or it can be sold on the mains. The water and steam released from the steam turbine is transferred back to the tank, whereby the system is closed and no water needs to be added. Salt, sea water, glycol may be added to the ice if desired, such as fluidity or a high freezing point which may be low, e.g. -6 ° C. It can, for example, be pumped into heat exchangers in pumps, which can act as coolers for air, refrigerators, freezers and the like. Liquid ice formation can be made centralized, so to speak of central cooling, or decentralized. Liquid ice can be moved hundreds of meters.

The liquid ice transfer duct is installed inside the ventilation duct. The ventilation duct does not need to be insulated because its surface does not condense because its internal and external temperature difference is not sufficient to produce a dew point because the coolness is transferred only in a well insulated liquid ice transfer piping.

For example, warm water is needed for washing even in warm conditions. It comes from a steam boiler. The hot water duct may be installed adjacent to the liquid ice duct in a pipe mounted in the ventilation duct. In this case, there is no need to go through structures more than one pass-through, which is a significant advantage especially in renovation sites. Liquid ice and warm water may have their own heat exchangers.

Conventional water cooling does not utilize latent heat at all. In the icing arrangement according to the invention, the proportion of latent heat can be 55%, whereby its overall efficiency is at most seven times better than conventional water cooling. The temperature of the incoming air close to 0 ° C is, of course, too low in housing conditions, but it can be used in some processes. There are several ways in which the low temperature can be raised in the invention, for example by increasing the amount of warm air, reducing the amount of ice. More specifically, the combined refrigeration, heating and power generating plant according to the invention is characterized in what is set forth in the characterizing part of claim 1.

The formula for the coefficient of performance is COP = Q1 (heat transfer) / W (work). Thermally, the air cannot be cooled, it can only be moved out of the room. The smaller the workload, the better the efficiency. The plant of the invention requires no external energy in addition to waste. A conventional compressor-driven refrigeration unit has an average COP of 2.7.

When the invention uses exclusively pure water as the heat transfer medium, its environmental effect is zero. Furthermore, when the invention optimally utilizes aqueous phase state changes, it has a high COP. When it uses no electricity at all but produces it in addition to cooling, overall efficiency is superior to any other technology on the market. And all the water is recycled in the process so you don't have to add it. In addition to cooling, it can also be a by-product of dehydration, desalination, sludge purification and the like.

The device according to the invention is simple, inexpensive, lightweight, maintenance friendly and does not contain hazardous substances.

The electrical connection power requirement of the device according to the invention is zero. In the invention, the so-called. instead of freon gases, only water is used. The invention has a wide range of uses: almost everything that is needed for refrigeration, for drying, for separating salt from water, for sludge purification.

Conventional refrigeration units have very long payback times. Heat pumps using outdoor heat pumps do not work in frost. Indoor heat pumps, on the other hand, do not benefit when the outdoor air is warmer than the indoor air. Their annual operating time is thus very short. Depending on the conditions in the warm regions of the United States and the average electricity prices there, the payback period of the plant of the invention may be as low as one year. The very good annual efficiency - the Seasonal Performance Factor (SPF) - is due to the long annual operating time, which is practically all year round as the device operates in summer and winter.

Various embodiments of the invention are set forth in the dependent claims. For example, skiing on ski slopes is possible with the traditional ice system only in frost, often it starts at 3 ° C. If the temperature rises to the plus side after snow, the snow starts to melt. To prevent this, a system has been developed for the country where the piping system is located, where cold liquid circulates. Of course, this system is expensive to build. Kekinstö offers two advantages for this purpose. First, the ice is crystalline ice, the size of the ice crystals is about 0.001 mm. An additional advantage is that it has a high heat capacity of 80 kcal / kg. Which means that compared to normal ice, it needs a lot of energy to melt, that is, using the same amount of energy, the crystallizer stays on ice longer. The advantage of preserving meat and fish, for example, is that the crystal is not broken by the cellular structure of Kuta's normal ice. Speaking of snowmaking, liquid ice can be made in warm conditions and lasts longer than normal ice.

US 5448892 describes a conventional vacuum process for producing water from ice (column 3, lines 10-21), but does not mention the steam-powered ejector as a vacuum generator. It relates to the desalting of seawater (column 3, lines 21-31) and is therefore not of the same class as the invention. Its class may be E03C while it may be F25B-J in the invention.

In WO 2006095055, the containers are not interconnected and do not use an ejector, unlike the invention. Thus, the patent class of the publication is F28D when it is F28C at the center.

WO 02077536 and WO 2012151429 show the general level of the invention as well as CN 201903217 U (FUJIAN SNOWMAN CO LTD), US 6672099 B1 YOSHIMI MANABU et al), JP2000338278 A (TOSHIBA CORP) and EP 0005825 A1 (EGOSI DAN). In the summary and Figure 1 of the jukebox CN 201903217 U, the steam is directed to an ejector which produces a vacuum sufficient for the water to evaporate and freeze, the ice being transferred to the tank. The publication differs from the arrangement according to the invention in that it does not mention the arrangement of the arrangement with the cooling, heating and power generating plant, nor the directing of its liquids to the heat exchanger, the injection of steam into the turbine or the use of waste heat for preheating.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which FIG. 1 schematically shows a cooling, heating and power generating plant and its air, gas and fluid or fluid flows, FIG. 2 shows a cross section of a cap and ducts. According to FIG. 1, the combined cooling, drying and power generating plant consists of a sealed water tank 1 connected by a conduit 2b to an ejector 2. Steam 2a is supplied to the Kim ejector 2, and the ejector conducts air through conduit 2b to equal or lower than the partial pressure of saturated water vapor, as a result of which the water in tank 1 begins to boil. At 21 ° C, for example, it has a maximum pressure pmax = 24.9 mbar. The energy needed for boiling is taken from liquid water, which eventually solidifies or freezes. The ice from the tank 1 is led to the tank 5, where, for example, salt is added to the ice so that liquid ice is formed from the ice, which is transferred via tube 6 to the heat exchanger 7 to cool the object. In the heat exchanger 7, the liquid ice melts into water, which is transferred back to the tank 1 by means of the pipe 6. In the areas requiring cooling, the recommended comfort temperature is about 23 ° C, which means that the temperature of air entering the space is significantly lower. The recommended relative humidity of the indoor air is up to 55%, so the relative humidity of the indoor air could be 40%. For example, to achieve a replacement air temperature of 16.8 ° C and a relative humidity of 40%, the air dew point is 3.14 ° C, 40 ° C and 90% RH, respectively. The dew point is 38 ° C.

The steam flow required by the ejector is produced, for example, by incineration or gasification of the waste material, heat is transferred to the water in the steam boiler 4, from where the steam is transferred to the ejector 2, from the steam 2c to the steam turbine 8. The waste heat from the steam turbine 8 is directed to the preheating of the combustion or gasification plant and the water and steam are transferred back to the tank 1 whereby the system is closed and no water and steam need be added.

A well-insulated liquid-cooled transfer tube 6 is mounted inside the ventilation duct 10, whereby the ventilation duct 10 does not need to be insulated, since cool air does not pass through the duct so that no dew point is formed. Fig. 2 shows an exceptional section of the ventilation duct 10, which has a pipe 6 installed therein, which has a duct 11 for liquid ice and another duct 12 for warm water. Even in warm conditions, water is needed. washing up. The hot water is obtained from the steam boiler 4. Both the liquid ice and the hot water 12 may have their own heat exchangers. When the duct 6 and the ducts 11,12 are located inside the ventilation duct 9, there is no need to pass through, for example, structures of buildings. At the renovation sites, pipes 6 and ducts 11,12 can be easily transported inside the ventilation duct 10.

The invention is applicable to buildings and transport equipment as well as industrial processes, refrigeration and freezing of meat, fish and agricultural products, refrigeration of various devices such as computers and electronics, drying in the food industry, agriculture, bakeries, etc., heating and power generation.

Claims (6)

A combined cooling, heating and power generation plant consisting of a watertight tank (1), a combustion or gasification plant (3), a steam boiler (4) and an ejector (2) having openings (2a, 2b, 2c), from a tank (5), a steam turbine (8), a generator (9), a pipe (6), a ventilation duct (10), characterized in that the steam produced by the combustion or gasification plant (3) is directed to the ejector (2). 2a), where (2.2b) is produced in the tank (1) a vacuum which is sufficient for the water to evaporate and freeze, the ice formed in the tank (1) is transferred to the tank (5) where it is converted into liquid ice, e.g. transferred to a heat exchanger (7) via a duct (11) mounted in the tube (6) where the ice has melted into water and the water is returned to the tank (1), the steam (2c) released from the ejector (2) is transferred to the steam turbine (8) to the generator (9), Mik is produced electricity and steam turbine (8) the waste heat is transferred to the combustion or gasification plant (3) for preheating and steam turbine of (8) released from the steam and the water is transferred back to the tank (1). Combined cooling, heating and power generating plant according to claim 1, characterized in that the hot water produced in the steam boiler (4) is conveyed via a duct (12) to a heat exchanger (7), for example for heating water and air. Combined cooling, heating and power generation plant according to claim 1, characterized in that a pipe (6) is installed inside the ventilation duct (10), in which various ducts for liquid ice (11) and hot water (12) are installed. Combined cooling, heating and power generating plant according to one of the preceding claims, characterized in that there are several heat exchangers (7) for, for example, liquid ice (11) and hot water (12). Combined cooling, heating and power generating plant according to one of the preceding claims, characterized in that its water, liquid ice and steam circulation is a closed system, whereby no need to add water. Combined cooling, heating and power generating plant according to one of the preceding claims, characterized in that it is used, for example, for heating air and water, for cooling air, refrigerators, freezers and freezers, computers, gsm base stations, data centers and processes such as snow and ice, cryogenic processes, desalination, sludge purification, drying, eg in the confectionery, meat and fish industries, and in power generation.