DE102010022902A1 - Method and device for operating cogeneration plants - Google Patents

Abstract

The invention relates to a method and apparatus for operating cogeneration units, by which power generation from the heat of the engine cooling allows and the power generation can be continued without heat loss without emergency cooling.
In a rotary piston engine that drives a generator for power generation, the piston chamber (40) is enclosed by a housing (41) in which hot water from a hot water tank (26) circulates under high pressure. In the hot water tank steam is generated, which acts on a connected to a second generator steam turbine (29). The exhaust steam of the steam turbine condenses in a hot water tank (50) which contains a heat exchanger (4) for heat supply of the housing complex.
The hot water tank and the hot water tank have a water connection and a level control for replacing the evaporated water.
In the absence of heat loss of the exhaust steam is directed into the open and the power generation in both generators can be continued.
The invention is particularly suitable for installed in large numbers in houses small power plants that replace dangerous and environmentally harmful large power plants.

Description

The This invention relates to a method and apparatus for Operating combined heat and power plants for power generation, for the space heating and for the warming of the Domestic hot water.

It can fossil fuels such as gasoline, diesel or natural gas, but also renewable energy, such as biogas, biodieser or vegetable oil. In both cases By combined heat and power plants, the energy sources are doubled used.

at the production of electrical energy from chemical energy sources, always falls to a thermal power, for space heating and can be used for heating domestic water. The energy consumption of the internal combustion engine becomes about one third into electrical energy and about two Third converted into thermal energy. For combined heat and power plants is the ratio of power generation and heat output constant, Electricity consumption and heat demand, however, are usually the same not this relationship. That's why for storage of thermal energy provided a hot water tank.

If however in the warmer seasons no space heating and little hot water is needed after a short time Time the hot water tank overheated, an emergency shutdown or emergency cooling is required. In addition, in warmer Countries more electricity for air conditioning and less Hot water needed for space heating.

The European Patent Application 1 962 362 A1 indicates the problem caused by the restriction of heat consumption in the summer months.

The The solution to the problem is that the exhaust gases be used with the help of fuel cells for power generation. This is the ratio of electrical power and Although thermal performance improved in favor of electrical power, Overheating of the hot water tank in the summer will then adjust later, but not prevented. fuel cells are exceptionally expensive and therefore become mainly for military purposes and used in space travel.

The publication DE 10 2008 003 333 A1 contains the proposal to drive a turbine with a generator through the exhaust gases of the internal combustion engine. As a result, the efficiency of the cogeneration plant is also improved, but not solved the problem of lack of heat loss in the summer.

Increasingly become combined heat and power plants of electricity suppliers in private houses set up, which you turn on if necessary by radio for power delivery. The power requirement arises especially when dependent on the weather Wind turbines fail. In case of insufficient heat loss but in the house system, the cogeneration plant but no electricity or an emergency cooling system with circulating pumps, large fans and high power consumption must be turned on become. It must then be used part of the electricity generated will destroy thermal energy.

The Invention has the task of solving this problem and the possibility to create the combined heat and power plant with better efficiency and particularly cost-effective to operate.

The Invention solves this problem by the cooling water of the internal combustion engine passed through a hot water tank, the heat supplied to the heat consumers, in case of missing or insufficient heat loss of the hot water tank heated to evaporation temperature, the further heat input resulting steam derived and the hot water tank the evaporation of the corresponding amount of water supplied is, with the promotion of cooling water off the hot water tank to the internal combustion engine while adjusting the Flow rate to the cooling demand and with a pressure which is higher than the vapor pressure in the hot water tank.

The The main advantages are that power generation for a home system and also for external customers unlimited can be continued if no or only low heat demand exists and for the necessary cooling no electricity is consumed. The operational safety is absolutely guaranteed because no switching devices, no circulation pumps and no fans necessary for emergency cooling are.

The Cooling of the internal combustion engine is therefore not carried out Contact of the coolant with the outside air, but by evaporation. The lower temperature difference between the cooling liquid and the cylinder walls is due to a higher flow rate of the cooling water pump balanced.

Of the Hot water tank can be heated up to 100 ° C and in a pressure-resistant container to much higher Temperatures. The flow temperature of the heating system is through Interposing a heat exchanger and a pump with Volume control easily adjustable. Due to higher temperatures becomes a larger heat supply for formed a later heat demand.

By further heating of the hot water storage evaporates the Water and is replaced by cold water. This does not limit the cooling capacity the power generation. The heat of evaporation of water is yes, as you know, very large and the water costs, which in This amount only incurred if the house is not sufficient Heat consumed amounts to less than 0.01 Euro / KWh while for the electricity at least 0.10 Euro / KWh remunerated becomes. The self-consumption of the house, the minimum of 0.20 € / KWh Saves, can be covered even in the absence of heat demand. Large power plants also consume large amounts of water (in Germany: 470 billion cubic meters per year), where the Power plant in the house plant still has the advantage that the transport losses accounted for electricity.

In High water price areas is a recovery by condensation by means of a steam outside air heat exchanger possible, which requires no pumps and fans.

Of the in the hot water tank in the absence of heat demand resulting steam drives according to another Embodiment of the invention with a generator generating electricity connected steam engine. This is a steam turbine, a piston steam engine or other engine.

The Power of the steam engine is increased by adjusting the vapor pressure greatly increased in the hot water tank, the Flow rate of the cooling water pump increased is at a higher cooling water temperature to achieve sufficient cooling.

The Cooling with cooling water temperatures make up for 100 ° C is possible because during the combustion process very high temperatures arise and thus the cooling necessary temperature difference is present. In the process, the water becomes kept liquid by higher pump pressure.

condensation minimizes the volume of water vapor and the resulting Pressure difference to the steam from the hot water storage ensures for the high speed of the steam at Drive the additional used for power generation Steam engine. Instead of destroying the heat Consuming electricity is added to the heat Electricity generated.

When Capacitor becomes an outdoor air / steam heat exchanger used. If this is difficult because of structural conditions, is proposed the exhaust steam of the steam engine in a hot water tank to direct where it condenses and heats a heat exchanger, which supplies the consumers in the house. Missing or too low Heat is dissipated steam and stored in the hot water tank missing water replaced.

Of the in the cooling of the internal combustion engine resulting steam can be derived directly into the environment, if the missing Heat consumption in power generation rarely occurs and the bigger investment for one Steam turbine and a second generator is not worthwhile. If the power generation is paramount, is inventively the Water vapor for additional power generation in a heat engine directed.

at too low power consumption and high heat demand is also proposed, an electric water heater to turn on in the heating circuit. It is known that the current consumption is too low and heat demand electrical heating resistors in to turn on a hot water tank, the water heater in the Heating cycle, however, takes effect much faster.

By The invention operates the combined heat and power plant with high power requirements and with any heat requirement with a good efficiency.

With simultaneous heat and Power Requirements:

Of the Hot water tank can be heated to 100 ° C and forms a larger reserve.

For electricity demand and lack of heat requirement:

Of the Hot water tank supplies steam for a steam engine, which a second generator for additional power generation drives or supports the internal combustion engine, thereby fuel is saved.

For heat demand and missing Power Requirements:

Of the Electricity from both generators gets into a water heater in the Heating circuit initiated and the space heating supplied immediately. At the same time, the cooling water circuit of the hot water tank heated.

Especially is advantageous as a combustion engine, a rotary piston engine to use, for example, a Wankel engine. These internal combustion engines are vibration-free, have a small footprint and are suitable for gaseous fuels very well suited. The heat output to the cooling water is lower than in reciprocating engines.

The device for carrying out the method according to the invention has a hot water tank with connections to the internal combustion engine and a cooling water pump, a heat exchanger with connections to the heat consumers in the house system, a water level regulator for the production of a water level with distance to the top of the water reservoir and a steam discharge.

By This distance will be in the hot water tank a large Surface for evaporation and a space below the steam outlet formed to collect the steam and this evaporation worried the Cooling of the internal combustion engine.

To Another embodiment of the invention is in the line between the hot water tank and a condenser a steam engine installed, which drives a second generator or the internal combustion engine supported. A pressure-resistant hot water storage tank receives a pressure control valve, this being at a pressure is set, which is lower than that of the cooling water pump generated pressure. Furthermore, a level switch is installed, the controls a solenoid valve for the supply water requirement.

The Exhaust gases of the internal combustion engine are passed through a heat exchanger passed and as known for overheating the steam used.

If the steam engine is a steam turbine, which in support the internal combustion engine is used, they must be through a gearbox and a clutch are connected. The transmission is required because the steam turbine has a higher speed has as the internal combustion engine and the clutch disconnects when no steam is available. The relief means lower consumption of natural gas, diesel etc.

embodiments The invention are illustrated in the drawings and are in Described in more detail below. Show it:

1 A combined heat and power plant in a house with evaporative cooling of the internal combustion engine.

2 A combined heat and power plant with steam turbine to support the internal combustion engine.

3 A combined heat and power plant with Wankel engine, steam turbine and an additional generator.

4 Use of the exhaust steam of the steam turbine.

On 1 is the internal combustion engine 1 with the generator 2 and the exhaust pipe 20 represented, which is supplied by gas, diesel oil or other energy sources with energy. Its cooling circuit consists of a cooling water pump 5 and a line 6 and is with the hot water tank 3 connected to a heat exchanger 4 contains. This heats over a pipe 8th with pump 7 via a mixing valve 13 the space heating circuit 10 with pump 9 , The water heater 11 will be over line 12 and heat exchangers 14 supplied with heat. The regulation is done by mixing valves 13 Having fresh water supply through water pipes 16 ,

A line 15 leads hot water to consumers. A check valve 25 secures the space heating cycle. The hot water tank 3 is through water pipe 17 via a float valve 19 supplied with water and he has a vapor extraction 18 , The power supply of the consumers in the house by the generator 2 via line 23 and the power supply to the outside via counters 24 and direction 21 , For exhaust and exhaust steam is a chimney 22 intended.

2 shows a pressure-resistant hot water tank 26 connected to the cooling circuit of the internal combustion engine via line 6 and pump 5 connected is. A pressure control valve 27 and a steam line 28 connect to a steam turbine 29 that have a gearbox 36 and a clutch 37 the internal combustion engine 1 supported. A capacitor 31 for the exhaust steam of the steam turbine 29 is installed outside the building. The hot water tank 26 contains a level switch 33 , which in case of lack of water a solenoid valve 34 in cold water connection 17 opens.

The exhaust pipe 20 directs the exhaust gases of the internal combustion engine 1 through an exhaust gas heat exchanger 32 which overheats the steam, to the fireplace 22 , The in the hot water tank 26 installed heat exchangers 4 provides the heat with the help of the pump 7 via lines 8th to the heat consumer in the house system, whereby for faster heat delivery, an electric instantaneous water heater 35 can be turned on.

3 shows a combined heat and power plant, in which the internal combustion engine is a Wankel engine whose piston chamber 40 from a cylindrical, pressure-resistant housing 41 is enclosed. The coolant is pumped by a pump 42 promoted in this case and kept liquid by increased pressure. Appropriately is the connection 43 near the place where in the piston room 40 the ignition of the fuel takes place. The generator 2 is with the Wankel engine through a belt drive 44 connected. The vapor pressure is through the pressure control valve 27 set, the pump 42 Cooling water with a higher pressure than the pressure in the hot water tank 26 in the case 41 initiates. The administration 28 leads the steam to overheat in the heat exchanger 34 , which has a pipe 46 is heated by the exhaust gases and then into the steam turbine 29 which is an additional generator 30 driving. The fuel-air mixture occurs at the connection 45 in the piston chamber 40 one and the pipe 20 directs the exhaust gases outside. The heat supply of the house takes place as in 2 shown.

On 4 an embodiment is shown in which as in 2 and 3 Steam in the hot water tank 26 generated and via the heat exchanger 34 into the steam turbine 29 arrives. The exhaust steam of the steam turbine 30 However, it is in a hot water tank 50 directed by a water connection 51 over Schwimmerschaltet 52 and solenoid valve 53 filled with water. The exhaust steam pipe 54 With a perforated part immersed in the water, the steam condenses and the heat is transferred to the heat exchanger 4 transferring the house via wire 8th and pump 7 supplied with heat. In the absence of heat demand, the container is heated to 100 ° C and with further heat supply steam over the line 55 dissipated.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1962362 A1 [0005]
• DE 102008003333 A1 [0007]

Claims (10)

Method for operating cogeneration units, for generating electricity, for space heating and for heating the process water, characterized in that the cooling water of the internal combustion engine passed through a hot water tank, the heat supplied to the heat consumers, heated in the absence or too low heat loss of the hot water storage to evaporation temperature Derived from the hot water storage, the evaporation of the corresponding amount of water, wherein the promotion of the cooling water from the hot water tank to the engine under adjustment of the flow rate to the cooling demand and with a pressure is higher than the vapor pressure in the hot water storage. Method according to claim 1, characterized in that that the resulting steam in the hot water tank in a steam engine connected to a power generating generator is directed. Method according to Claims 1 and 2, characterized that increases pressure and temperature in the hot water tank and steam with higher pressure of the steam engine supplied while the delivery rate the cooling water pump is increased. Method according to Claims 1 and 2, characterized that the steam engine is supplied with steam, which overheated in a heated by the exhaust gases of the internal combustion engine heat exchanger becomes. Method according to Claims 1 and 2, characterized that the exhaust steam of the steam engine for condensation in a Hot water tank guided, there via a heat exchanger the consumers in the house supplied and too little or missing Heat dissipation is derived. Apparatus for carrying out the method, characterized characterized in that the internal combustion engine is a rotary piston engine is, the piston chamber of a predominantly rotund, pressure-resistant container is surrounded and the connections with a pump to a Has hot water tank. Device for carrying out the method, characterized in that the cooling circuit of the internal combustion engine ( 1 ) by a hot water storage ( 3 ), which is a vapor extraction ( 18 ), a cold water connection ( 17 ) with water level controller ( 19 ) and a heat exchanger ( 4 ) with connection to the heat consumer owns. Apparatus for carrying out the method, characterized characterized in that the vapor pressure in the hot water tank is adjustable by a pressure control valve. Device for carrying out the method, characterized in that the exhaust pipe ( 20 ) with a heat exchanger ( 32 ) is connected by the steam line ( 28 ) to the steam turbine ( 29 ) leads. Device for carrying out the method, characterized in that a perforated exhaust steam pipe in the Water of the hot water tank is immersed.

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