JPS5922043B2 - Cold energy power generation plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a Rankine cycle cold energy power generation plant, and more particularly, to a cold energy power generation plant that enables circulation of a cycle working medium even in the event of a power outage or failure of a cycle condensate pump.

In conventional cold energy power generation plants, in the event of a power outage or condensate pump failure, the cold energy power generation plant is shut down and the supply of working medium to the condenser is cut off, causing the heat source on the refrigerant side of the condenser, such as LNG, to disappear. The drawback was that even the refrigerant system, which had no problems, had to be shut down.

Particularly when the refrigerant is the fuel for a power plant, the loss of the heating source for the refrigerant is a problem that must be avoided at all costs.

An object of the present invention is to provide a cold energy power generation plant in which the working medium of a turbine is used as a heat source on the refrigerant side in a condenser, even when the pump that feeds the working medium to the evaporator stops for some reason. It is an object of the present invention to provide a cold energy power generation plant that enables circulation of the medium and allows the refrigerant side system to continue operating.

A feature of the present invention is that the working medium condensed liquid level in the condenser real well is located higher than the liquid level in the evaporator where the working medium is evaporated, so that even when the pump is stopped, the liquid level drop between the two is maintained. The vapor side of the working medium is normally led to the evaporator and the condenser through the bypass passage of the turbine, and the condensed side of the working medium is passed through the bypass passage of the pump to the evaporator from the condenser. This allows the working medium to circulate, and this natural circulation allows heat to continue to be transferred from the working medium to the low-temperature refrigerant such as LNG in the condenser, thereby interfering with the operation of the system on the refrigerant side. This is because we tried to prevent this from happening.

Next, a power generation plant using a refrigerant, which is an embodiment of the present invention, will be described.

In FIG. 1, a condenser 1 condenses the working medium of the cycle through heat exchange with a refrigerant such as LNG.

Normally, the refrigerant enters the condenser 1 in a liquid state 13, is heated by a working fluid, evaporates, becomes a vapor state 14, and is supplied to necessary equipment (not shown).

Further, the condenser 1 exchanges heat with the refrigerant, and the condensed working medium is stored in the real well 2 at a level above the liquid level 20 .

Furthermore, the medium is a real well 27) and a pump artificial tube 1.
2 and is pressurized by the condensate pump 3, then flows into the evaporator 4 through the liquid supply pipe 11, and is stored at a level equal to or higher than the liquid level 21.

Note that a pump bypass pipe 18 is disposed in the pump inlet pipe 12.

The working medium supplied by the condensate pump 3 is heated and evaporated in the evaporator 4 by a relatively low temperature heat medium 15 such as seawater or exhaust gas.

The evaporated medium is transferred to the main steam pipe 10 and the turbine inlet shutoff valve 5.
It passes through the turbine 6, performs work in the turbine 6, and is extracted as electric power by a generator 7.

The working medium exhausted from the turbine 671 is received into the condenser 1 through the turbine exhaust pipe 19.

Note that the turbine 6 has a bypass pipe 9 equipped with a bypass valve 8.
is installed.

Here, in the condenser pedestal 16 on which the condenser 1 is installed and the evaporator pedestal 17 on which the evaporator 4 is installed, the liquid level 20 of the condenser real well 2 is the liquid level 2 of the evaporator 4.
The condenser 1 and the evaporator 4 are arranged so that the condenser 1 and the evaporator 4 are higher than 1 by H.

This H is determined so that the required amount of the working medium in the real well 2 flows into the evaporator 4 by natural flow even when the pump 3 is stopped.

In addition, the evaporated working medium flows through the turbine bypass pipe 9 into the condenser 1 to form a natural circulation cycle.

In general, the cold energy utilization system is an accessory to the main system, so even when the cold energy utilization system is tripped, if the refrigerant is LNG or the like and is used as fuel for the thermal power plant that is the main system, this LN()k It is absolutely impossible to stop it.

In this case, by applying the present invention, it is possible to avoid stopping the LNG side, that is, the main system, even when the condensate pump 3, etc., which is said to frequently fail in the case of image width, trips or during a power outage. It is.

In applying the present invention, it is desirable to reduce the amount of (2) as much as possible in terms of equipment costs, so the bypass valve 8 on the bypass pipe 9 is opened to reduce the flow resistance in the cycle. The working medium is made easy to flow into the condenser 1, and the pump bypass pipe 18 is opened to make it easy for the condensed working medium to flow down to the evaporator 4, thereby promoting the natural circulation function.

Therefore, according to the present invention, in a cold energy power generation plant in which the working medium of a turbine is used as a heating source on the refrigerant side in a condenser, even if the pump that supplies the working medium stops for some reason, It is possible to achieve the effect of realizing a cold energy power generation plant in which the circulation of the medium is enabled and the operating skeleton of the system on the refrigerant side can operate.

[Brief explanation of drawings]

FIG. 1 is a system diagram of a cold energy power generation plant that is an embodiment of the present invention. 1... Condenser, 2... Real well, 3... Condensate pump, 4... Evaporator, 6... Turbine, 9 ...Bypass pipe, 13...Liquid gas, 14...Gas gas, 15...Heating medium, 16...Condenser mount, 17 ...Evaporator stand, 18.
... Pump bypass, 20 ... Real well liquid level, 21 ... Evaporator liquid level, H ......
・Liquid level difference.

Claims (1)

[Claims] 1. A turbine that performs work using a working medium, a condenser equipped with a real well that exchanges heat with a cold medium and condenses the working medium that has passed through the turbine, and is installed on a water supply system to supply the condensed working medium in the condenser. In a cold energy power generation plant having a pump that heats and vaporizes a working medium supplied by the pump, the real well liquid level of the condenser is located higher than the liquid level of the evaporator. The condenser and the evaporator are respectively disposed, the turbine is provided with a bypass flow path for guiding the working medium to the condenser, and the water supply system is further provided with a pump bypass flow path that bypasses the pump. A cold energy power generation plant.