JPS58178810A - Low-heat power generating equipment - Google Patents

Abstract

PURPOSE:To keep the gasification of cold liquified gas in a condensor by a method wherein a liquid level adjuster is arranged in the condensor and the pump is not stopped even if the thermal medium level in the condenser is decreased lower than the specified liquid level. CONSTITUTION:When the liquid level of cold liquified gas, for example, the liquid level of propane in a condensor 1 is decreased lower than the specified liquid level due to a reduction in a volume of condensation, the signal from a liquid level adjuster 21 is preferentially selected by a selector switch 22 and a liquid level adjuster valve 4 is operated in its closing direction. Therefore, the volume of propane which is increased pressure by the pump 3 and fed to an evaporator 5 through the liquid level adjuster valve 4 and via conduits 15, 16, respectively, is decreased and the liquid level of the propane in the condensor 1 is recovered to one more than the specified liquid level. When the liquid level of the propane in the condensor 1 is higher than the specified liquid level, a signal from the liquid level adjuster 6 is selected by the selector switch 22 to control the degree of opening of the valve of the liquid level adjuster valve 4 and thereby the liquid level of the propane can be adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention 1'i relates to cold power generation equipment, particularly cold power generation equipment having a Rankine cycle.

An example of conventional cold power generation equipment will be explained with reference to FIG.

FIG. 1 is a system diagram of a cold power generation facility that uses propane as a heat medium and uses the cold heat of a low-temperature liquefied gas, for example, LNG, to generate electricity.
abbreviated as condenser). Here, propane at atmospheric pressure and −43° C. entering from the conduit 18 is condensed by LNG. As a result, the LNG is vaporized to -50°C and then passed through the conduit, and is sent out as fuel from the conduit 13 as natural gas at a temperature of 0°C or higher using seawater from the conduit that enters the warmer 2I.

On the other hand, propane condensed by LNG passes through a conduit 14, enters a heat medium pump (hereinafter referred to as pump) 31, is pressurized from atmospheric pressure to a predetermined pressure, and passes through a liquid level control valve 4 to a conduit 15.
．． The heat medium is supplied to a heat medium evaporator (hereinafter referred to as evaporator) 5I via 16.

evaporation! R5 is a system in which the opening degree of the liquid level control valve 4 is controlled by the liquid level regulator 6 to adjust the supply amount of propane so as to maintain the liquid level of evaporated propane at a constant level. In such a system, if LNG suddenly decreases, the amount of propane condensed in the condenser 1) or the liquid level decreases due to a decrease in μ, or the amount of liquid held in the evaporator 5 and the amount of gropan liquid held in the condenser 1 decrease. The evaporator 5 is structurally larger, and even if there is a slight fluctuation in the liquid level in the evaporator 5, the fluctuation in the propane liquid level in the condenser 1 appears as a relatively large fluctuation. In particular, in pump 3, there is a possibility that cavities may occur due to a drop in liquid head pressure on the suction side. The pump 3 is damaged due to the occurrence of cavities and re-drip.

In such cold power generation equipment, if the heat medium liquid level in the condenser falls below the specified level, the pump will stop and the heat medium cannot be circulated, so the entire equipment will have to be stopped and the condensation will occur. The drawback was that the vaporization of the low-temperature liquefied gas in the vessel could not be sustained.

The present invention is aimed at eliminating the above-mentioned drawbacks, and includes providing a liquid level regulator in the condenser and transmitting a signal from the liquid level regulator when the heat medium liquid level in the condenser is below a specified level. An automatic signal selector is connected to the liquid level control valve and operates the liquid level control valve provided between the pump and the evaporator in the closing direction. The feature is that the liquid level regulator installed in the condenser and the liquid level regulator installed in the evaporator are connected to each other, and the cold power generation equipment is capable of sustaining the vaporization of low-temperature liquefied gas without stopping the pump. This is what we provide.

An embodiment of the present invention will be explained with reference to FIG.

FIG. 2 is a four-way diagram of the cold-heat power generation equipment according to the present invention. In FIG. 2, the same equipment (a) as in FIG.

In FIG. 2, the condenser #II 1 is provided with a liquid level regulator 21, and the liquid level regulating valve 4 is connected and provided with an automatic signal selector, for example, a selector switch n.

The selector switch η indicates that the liquid level of the heat medium, for example, propane, in the condenser 1 has become below the specified liquid level.

In this case, the signal from the liquid level regulator 21 is preferentially selected and the liquid level regulating valve 4 is operated in the closing direction. The liquid level regulators 6 and 21 are connected to the selector switch 22G, respectively.

Now, if the liquid level of propane condensed by low-temperature liquefied gas such as T or NG in the condenser 1 drops below the specified liquid level due to a decrease in the amount of propane condensed, the liquid level controller 21 The signal is preferentially selected by the selector switch n, and the liquid level control valve 4 is operated in the closing direction. Therefore, the amount of propane that is pressurized by the pump 3 and supplied to the steamer 51i via the liquid level control valve 4 and the conduit 15.16 decreases, and the propane liquid level in the condenser 1 recovers to above the specified liquid level. do. In addition, when the propane liquid level in the condenser 1 is below the specified liquid level, the signal from the liquid level regulator 6 is selected by the selector switch n, and the valve opening degree of the liquid level regulating valve 4 is controlled, and the evaporator 5 The propane liquid level is adjusted.

In the cold power generation equipment like this example, when the propane liquid level in the condenser drops below the specified liquid level, 4. The signal from the liquid level regulator installed in the condenser is prioritized by a selector switch. By selecting and operating the liquid level control valve in the closing direction, the propane liquid level in the condenser is restored to the specified liquid level or higher, thereby preventing the pump from stopping and allowing LNG to continue vaporizing.

As explained above, the present invention provides a liquid level regulator in the condenser, and transmits a signal from the liquid level regulator only when the heat medium liquid level in the condenser becomes below the specified liquid level. An automatic signal selector is connected to the liquid level control valve and operates the liquid level control valve provided between the pump and the evaporator in the closing direction. By connecting the two liquid level regulators and the liquid level regulator on the evaporator, it is possible to operate without stopping the entire facility, allowing continuous vaporization of low-temperature liquefied gas in the condenser. There is an effect that can be achieved.

[Brief explanation of drawings]

FIG. 1i is a system diagram of a conventional cryogenic power generation facility having a Rankine cycle, and FIG. 2 is a system diagram showing an embodiment of a cold power generation facility having a Rankine cycle according to the present invention. l...Condenser, 3...Pump, 4...
・Liquid level control valve, 5... Evaporator, 6.21 Curved liquid level regulator, 7... Heat medium expansion turbine, 8... Generator, 11.12.14 to 18. ... Conduit, n...
・Selector switch・7 Ogo diagram

Claims (1)

[Scope of Claims] 1. Consisting of a heat medium condenser, a heat medium pump, a heat medium evaporator provided with a liquid level regulator, a heat medium expansion turbine, and a generator, the heat medium pump In a cold power generation facility having a Rankine cycle in which a liquid level control valve is provided between the heat medium condenser and the heat medium evaporator, it is common to provide a liquid level regulator in the heat medium condenser. An automatic signal selector is connected to the liquid level control valve, which selects the signal preferentially only when the liquid level in the heat medium condenser is below a specified liquid level and operates the liquid level control valve in the closing direction. A cold-thermal power generation facility characterized in that a liquid level regulator provided in a heat medium condenser and a liquid level regulator provided in the heat medium evaporator are respectively connected to an automatic signal selector. 2. The cold heat power generation equipment according to claim 1, wherein the automatic signal selector is a selector switch.