RU2537661C1 - Periodic acting thermal energy storage - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: periodic acting thermal energy storage containing in the heat insulated housing a heat accumulator from solid high-temperature working medium with the channels for the flow of heat transfer gas, input and output unions for it, tubular electric heaters, ventilator, connected to the output union of the housing, the automation unit for determination of the operating time with the night tariff of the electric power and for processing of signals from temperature transmitters in heat accumulator and consumers, it contains in addition the connected water heat accumulating storage, the housing of which contains the tubular heat exchanger with input and output unions, connected through the ventilator respectively to output and input unions of the heat accumulator, backup peak tubular electric heater, output and input union of hot water supply for consumers by means of additionally enabled pump, and tubular electric heaters, ventilator and pump are connected to the automation unit.

EFFECT: decrease of costs.

3 cl, 1 tbl, 1 dwg

Description

The present invention relates to heat energy accumulators that are charged from electric energy periodically at a given time, for example, when using a cheaper nightly rate for electricity and the delivery of thermal energy to consumers at their request at other times of the day.

Well-known "Heat accumulators" - liquid systems for the storage of thermal energy, for example, the company HEATLEADER (Heatlider), [electronic resource]. Access mode http://www.heatleader.ru [1] with a volume of up to 100,000 liters at a water temperature of 95 ° C (analogue), JÄSPI heat accumulators [electronic resource]. Access mode http://kaukora.fi/ru/nodel87 [2] (analogue) and others.

However, due to the limited specific heat capacity of water, the heat storage tanks of enormous sizes, which are impossible or inexpedient to place inside the objects, are required to supply thermal energy to the building and other larger objects. The construction of a separate structure outside the building requires additional significant costs for materials for insulation in order to ensure minimal heat loss.

In connection with the above, a similar electric heating with heat accumulation in autonomous water tanks is used mainly only for hot water supply (DHW) and, in part, for heating small rooms.

Also known are electric “Heat Storage” (VT) compact volumes with periodic operation of LLC “Tagil-Technoterm” [Electronic resource]. Access mode http://www.tagiltt.ru [3] for power up to 5 kW, StiebelEltron [Electronic resource]. Access mode http://electrocente.com.ua for power up to 7 kW [4] and a number of other foreign companies containing a central high-temperature core of magnesite or talc chloride (analogues). The working fluid in these heat accumulators is the air of heated rooms.

The automation unit of these devices controls the inclusion of thermoelectric heating elements (TEN) at night, which heat the core in a thermally insulated casing to 600-650 ° C. In the daytime, by convection or by means of a fan, hot air is forced out of the housing, mixing with the cold air of the room.

The disadvantages of these analogues are as follows:

- Only air heating of rooms with power consumption up to 5 ... 7 kW is provided.

- The part of the air that has passed the temperature of 600 ... 650 ° C is called "dead" heavy air devoid of negative air ions.

- Already at temperatures above 100 ° C, the amount of oxygen in the inhaled air burns out (decreases).

In this regard, such products are not recommended for long-term use (see, including the Conclusion of the section of the MTS "Mosenergosbyt") (Appendix 1 to this application).

The closest in technical essence (prototype) is "Stationary heat accumulator used for heating rooms for various purposes." Utility Model Certificate No. 40759, IPC class. E04B 1/74. Author Anisimov A.M. [5].

These heat accumulators are structurally made in the form of a wall or furnace, in which heaters of the corresponding power up to 100 and more kW are laid. The set large volumes of the solid core of the talcochloride structures allow the accumulated heat to heat large rooms or small buildings.

Thermal energy from the device is also transmitted by natural convection or by changing the speed of rotation of the fan, which supplies hot air to the premises. Thermal insulation of the body is provided by basalt mats, blocks based on schungizite and vermiculite.

The main disadvantage of the prototype, as well as analogues, is that it provides only air heating of the premises.

In addition, the high temperature of the same order as that of the analogs, in the zone of contact of the heating elements with the core of talc chloride, creates the conditions for the burning of oxygen and the reduction of negative aero ions in indoor air.

This is due to the fact that the device pumps the air of the room into its structure, passes part of it through the high-temperature zone and mixes it again with the cold part of the air. Thus, the movement of the air flow is open-ended with the gradual mixing of the unhealthy part of the air, which is especially important for poorly ventilated rooms.

The task of the invention is to remedy these disadvantages of the prototype, expanding its scope for both heating and domestic hot water.

The claimed object in comparison with the known device has the following distinctive advantages.

- Hot air from the heat accumulator with a solid core does not directly enter the room, but is supplied in a closed circuit to the coil - the tubular heat exchanger of the water heat storage accumulator and then returns to the heat accumulator.

- The next advantage is that the proposed “Battery of periodic thermal energy” is easily integrated into the existing hydraulic heat supply system, which has a pipe interchange, heating registers, etc., as an autonomous micro-mini-boiler using an economical mode of operation at a night rate.

- The next advantage is that the thermal storage drive is equipped with an additional heating element, which is switched on by the automation unit, as well as the heating element heating accumulator with a solid working fluid, when operating at a night rate, intensively heating water.

In the daytime, additional heating of the water during its analysis by consumers is carried out from a heat accumulator with a solid working fluid.

Another advantage is that graphite blocks with channels for gas flow are used as the heat accumulator working medium.

Another advantage is that carbon dioxide is used as the heat transfer gas, which, when heated above 125 ° C, reaches its supercritical state and obtains the properties inherent in liquids.

These advantages compared to the prototype provide a technical result, which consists in increasing the accumulated heat energy by the battery and expanding its functions as a device for heating not only indoor air, but also water for heating and hot water supply at the most favorable (cheap) tariffs for electricity.

As a result of a search by sources of patent and scientific and technical information, the totality of features characterizing the described “Battery of thermal energy of periodic action” was not found. Thus, the proposed technical solution meets the criterion of "novelty."

Based on a comparative analysis of the proposed solution with the prior art according to the sources of patent and scientific and technical information, it can be argued that between the set of distinctive features, their functions and the task achieved, the proposed technical solution does not follow explicitly from the prior art, therefore, meets the eligibility criterion " inventive step ".

The proposed technical solution can find application in public utilities in the integrated supply of thermal energy for heating and for hot water supply to various consumers. The use of a cheaper tariff for unclaimed electricity at night and the delivery of thermal energy to consumers at their request at another time of the day helps to equalize the load schedule of electric networks.

The structural diagram of the "Battery thermal energy of periodic action" is shown in the drawing. The structure of the "Battery 1 thermal energy of periodic action" includes a heat accumulator 2 in a thermally insulated housing, containing a high-temperature working fluid 3 with channels for the passage of gas flow, a heat-electric heating element (TEN) 4, outlet 5 and inlet 6 for circulation of the gas flow through the fan 7 .

To the heat accumulator with a high-temperature working fluid, there is additionally connected a water thermal storage accumulator 8 of thermal energy in a thermally insulated housing, comprising an inlet 9 and an outlet 10 connected, for example, by a tubular heat exchanger 11, as well as a heating element 12, a water make-up valve 13, an outlet 14 and inlet fitting 15, connected by means of a pump 16 to the heating networks of consumers 17.

The “periodic thermal energy accumulator” is controlled by the automation unit 18 according to signals from a timer (program clock), external temperature sensors (t ° C) indoors, weather sensor, temperature sensors inside a heat accumulator with a solid working body and inside a water storage tank (in the drawing not shown).

The proposed device operates as follows. In the charging mode, at the command of the timer of the automation unit 18, the time range with the lowest cost of kilowatt-hour of electric energy at night in this region is selected and connected to the network TEN 4 of heat accumulator 2 and TEN 12 of heat storage accumulator 8 of thermal energy. When the set temperature is exceeded (t ° C), the sensors issue a command to the automation unit 18 to turn off the corresponding heating elements.

The consumers 17 are supplied with heat for heating and hot water supply by the circulation of hot water from the water thermal storage tank 8 through the outlet fitting 14, the pump 16, the consumer network 17 and the inlet fitting 15.

Make-up of the thermal storage tank 8 with water, when it is parsed by consumers, is carried out through the valve 13.

After partial cooling of the water in the accumulator 8 in the heat-discharge mode, the automation unit 18, according to the readings of the sensors, gives a command to turn on the fan 7, which distills the hot air along the circuit: outlet nozzle 5 of the heat accumulator 2, fan 7, inlet nozzle 9 of the water accumulator 8, heat exchanger 11, the outlet fitting 10 of the water storage device and the inlet fitting 6 of the heat accumulator 2 with a working fluid 3.

The high-temperature working fluid 3 has channels for passing through them a gas stream and intensive gas extraction of thermal energy from the working fluid.

Manufacturers of heat accumulators with a core from a solid working fluid use magnesite [3, 4] or talc chloride [5], which have an operating heating temperature of 600 ... 650 ° C.

In accordance with paragraph 2 of the claims, it is proposed to use graphite as a high-temperature working fluid. Comparison of the main properties of magnesite and graphite are shown in table 1.

Table 1 THERE Temperature ° C (max.) Specific heat, kJ / kg · K The coefficient of thermal conductivity, W / m · K Magnesite 1700 0.8 ... 1.1 1.7 ... 2.8 Graphite 3500 2.0 40 ... 170

Currently, graphite is produced by industry in large volumes as a moderator of reactions in uranium blocks of nuclear power plants, for a number of other technological purposes, and can be used as a high-temperature working fluid in the proposed heat accumulators. It follows from the table that the maximum permissible heating temperature and specific heat are almost two times higher, and the coefficient of thermal conductivity, on which the rate of transfer of thermal energy to the intermediate coolant depends, is many times higher.

In accordance with paragraph 3 of the claims, it is proposed to use carbon dioxide instead of air in this closed system, which, when heated above 125 ° C, becomes supercritical. In this state, carbon dioxide acquires the properties inherent in a liquid, its thermal conductivity and density sharply increase, which makes it possible to intensify the heat transfer process between the heat accumulator 2 with a solid high-temperature working fluid and a water thermal storage tank 8.

The daily load schedule of electric networks has pronounced peaks and half peaks of energy consumed during the day. For example, for a city of one and a half million people, the difference between the daily peak of consumed electric power and the night minimum is 300 ... 350 MW.

In patents of the Russian Federation [6, 7] it is recommended to install autonomous peak heat sources for subscribers.

As such sources, it is possible to use the proposed “Battery of thermal energy of periodic action” in cases where obsolete equipment does not provide the necessary heat capacity with worn-out slag networks, as well as in case of new construction as an autonomous micro-boiler room.

According to the authors, the claimed invention meets the condition of "industrial applicability", because the components of the device and the device as a whole can be used in the power system, the claims confirm the possibility of implementing the device with the described means to achieve the stated result.

The introduction of large amounts of such thermal batteries using nightly “failed” energy among individual consumers will contribute to the task of leveling the daily load schedule of electric networks, which is currently an urgent task for the power system.

Information sources

1. HEATLEADER heat accumulators [electronic resource]. Access mode http://www.heatleader.ru (analogue).

2. Heat accumulators of the company JÄSPI [electronic resource]. Access mode http://www.kaukora.fi/ru/node187 (analogue).

3. Heat storage TH2520 ... TH2550 LLC Tagil - Technoterm [electronic resource]. Access mode http://www.tagiltt.ru (analogue).

4. Heat storage ETS200 ... ETS700 firms StiebelEltron, ADL-2012-5030 firms ELNuR and others. Representative office in Ukraine [electronic resource]. Access mode http: /electrocente.com.ua (analogues).

5. Stationary heat accumulator (STE), used for heating rooms for various purposes. Utility Model Certificate No. 40757, IPC class. E04B 1/74. Author Anisimov A.M., Petrozavodsk, 185003, ul. Kalinina, 25, LLC Energoresurs-STE (prototype).

6. The method of heat supply. RF patent No. 2235249, cl. F24D 3/08. Authors: Sharapov V.I., Orlov M.E., Rotov P.V.

7. Heat supply system. RF patent No. 2235250, cl. F24D 3/08. Authors: Sharapov V.I., Orlov M.E., Rotov P.V.

Claims (3)

1. A batch heat pump containing a heat accumulator in a thermally insulated housing made of a solid high-temperature working fluid with channels for the flow of heat-transfer gas, inlet and outlet fittings for it, heating elements, a fan connected to the outlet fitting of the housing, an automation unit for determining night time tariff for electricity and signal processing from temperature sensors in the heat accumulator and among consumers, characterized in that an additional water thermal accumulator is connected a storage tank, in the housing of which there is a tubular heat exchanger with inlet and outlet fittings connected through a fan to the outlet and input fittings of the heat accumulator, a backup peak heating element, an outlet and input fitting for supplying hot water to consumers by means of an additionally introduced pump, and heating elements, fan and pump are connected to the automation unit. 2. The periodic heat accumulator according to claim 1, characterized in that graphite blocks with channels for gas flow are used as the working medium of the high-temperature heat accumulator. 3. The periodic heat accumulator according to claim 1, characterized in that carbon dioxide is used as the heat transfer gas.

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