JPS58171492A - Working fluid for rankine cycle - Google Patents

Abstract

PURPOSE:To provide a novel working fluid for Rankine cycle, having high energy conversion efficiency and high stability at high temperature, by mixing chlorodifluoromethane with difluoroethane. CONSTITUTION:The objective working fluid is prepared by mixing (A) usually 60-95wt% of chlorodifluoromethane with (B) usually 5-40wt% of 1,1- and/or 1,2-difluoroethane. USE:Suitable especially as a working fluid of a cycle having small temperature difference of the heat sources, such as ocean thermal difference power generation utilizing the temperature difference between the cold deep sea water and the hot surface sea water of the ocean.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel working fluid for run-on cycles.

A cycle is carried out in which a liquid medium is heated and evaporated using heat energy f- and expanded in an expansion device to obtain a mechanical fuel f-, which is then condensed and added by a pump to form a liquid medium. In the Ugyu Cycle, which converts heat energy into mechanical energy by repeated cycles, water is used as the medium, that is, the working fluid for the Ranki Cycle, which has traditionally been used. It is. Water as a working fluid has been used in steam engines for a long time. However, since water has a high freezing point and a large steam specific volume, its range of use is limited, and especially when a low-temperature heat source is used, the disadvantage is that the equipment becomes large and the efficiency decreases.

Many organic working fluids have been proposed to improve the drawbacks of water, but many of them are flammable or corrosive, so there are still no books that can be used satisfactorily. It has not yet grown.

In particular, from the perspective of effective use of energy, the use of bell heat sources with various temperatures has recently been promoted, and for low temperatures, LNG cold energy,
For high temperatures, #I sources such as waste heat and geothermal heat are used.

Among them, difluoro, methane ()O is used as a working fluid for heat sources in the low temperature range of -25℃ to 100℃.
However, the working fluid for the Lanxi cycle consisting of Freon 22 has a low conversion efficiency from heat energy f- to mechanical energy f-.・As a result of repeated research in order to meet such demands, the inventors of the present invention discovered that while the conventional operation is based on a single component substance, we have developed a system that mixes and mixes substances that each have different characteristics. It was found that nine working fluids have superior properties compared to single substances.

In particular, it is used as a working fluid for cycles with small heat source temperature differences, such as ocean temperature difference power generation that utilizes the temperature difference between deep low-temperature seawater and shallow high-temperature seawater.
It was discovered that a mixed medium of 2) and difluoroethane (152) had excellent properties, and the present invention was completed.

The mixed yarn of the fold 22 and the fold 152 of the present invention is
It has the following characteristics as a working fluid for cycycle.

Firstly, in the Lanxicycle using a mixed system of methane and difluoroethane, the mechanical energy f-1 obtained from IAR Enel f-1, that is, the energy fluctuation efficiency, is It has sufficiently higher characteristics than Freon 22, which is used as a fluid.

Second, although high stability is required as an important property for a working fluid for Lanxicycle, the fluoride of the present invention does not decompose at room temperature;
It maintains high stability even at high temperatures. This mixture also has the same high stability.

Furthermore, although difluoroethane is flammable, its flammability can be reduced by mixing it with 00 difluoro 0 metal, and a composition with a large mixing ratio of 00 difluoro 0 metal has no flammability.

The difluoroethane of the present invention has two isomers: 1,
It does not matter whether it is I-difluoroethane or 1,2-difluoroethane, or a mixture thereof.

FIG. 1 is a pressure-ental diagram (p-ttH
In the figure, the composition is 90% oO difluoromethane and 10% difluoroethane.

Figure 2 is a system diagram of the Ranxi cycle for converting thermal energy f- into mechanical energy f-, and Figure 3 is a Ranxi cycle using a mixture of 00 difluoro methane and difluoroethane as the working fluid. The temperature - ent oeM
It is shown written on the diagram. Note that the alphabets (A" to E) in FIG. 2 correspond to the state points indicated by the alphabets (A, E) in FIG. 3.

The working fluid heated by the steam generator (4) evaporates and becomes high-temperature, high-pressure steam. This state is represented by υ and ■ in Figure 3.
, indicated by the change in prisoners. During this time, the liquid working fluid is heated, its temperature rises, and the entire amount begins to boil. This working fluid vapor then enters the expansion bag @ (1) and undergoes adiabatic expansion, resulting in a decrease in temperature and temperature, as shown in Figure 3 (2)-■
Do the work in between. The working fluid, which has undergone work in the expansion device () and has become low temperature and low pressure, then enters the condensation device (2) and is condensed and liquefied as shown by @-○ in FIG.

This liquefied working fluid enters the pump (3), is pressurized, and enters the steam generator (4) again, repeating the cycle described above. Note that the middle point (a) in Figure 3 shows the state when warm seawater, which is the heat source, enters the steam generator of the Lanxi cycle, and <b> shows the state when the warm seawater leaves the steam generator. The arrow on the straight line from point (d) to point (A) indicates the direction of flow of warm seawater. In addition, points (→<1> indicate the state of cold seawater in the condenser, (7) indicate the state of cold seawater in the condenser, (4 indicates the state of cold seawater at the condenser inlet, and (I) indicate the state of cold seawater in the condenser. Indicates the condition of cold seawater at the outlet, and indicates the condition of the cold seawater at the outlet (
The arrow on the straight line from b) to point <1> indicates the direction of the flow of cold seawater.

As the expansion device used in the above-mentioned Lanxi cycle, a rotary or reciprocating type expander or a turbidity expander can be used, and as a steam generation device, it is the same as a boiler used to generate steam. For condensation equipment, the type used in refrigeration equipment can be used.As for pumps and closures, organic solvents commonly used in chemical equipment can be used. A pressurized liquid pump can be used.

Next, the present invention will be explained in more detail by way of examples.

EXAMPLES According to the cycle shown in Figures 1 to 3 above, the mixture of 900 difluoro methane and difluoroethane of the present invention and the single component 900 difluoro methane were used as working fluids under the following conditions. did.

(1) Warm seawater 1) Flow rate 27,000 tam/kr i) Evaporator inlet humidity 30°C (point a in Figure 3) i) Evaporator outlet temperature 27.5°C (point in Figure 3) (2) Cold seawater i ) Condenser inlet temperature 6.3°C (point d in Figure 3) i) Condenser outlet temperature 8.8°C (point in Figure 3) (3) Medium condensing temperature 10°C, 11°C, +2°C Results is shown in Table 1. In other words, the power generation output obtained using warm seawater is F0. :/15'2 The mixed working fluid is large. Furthermore, it is clear that the output increases as the mixture composition of Freon 152 increases, and for each condensation temperature of 10°C, 11°C, and 12°C, the maximum output can be obtained at Tojiro where the composition of Freon 152 is around 30%. It was.

As described above, the Freon 22/Foxy 152 mixed system of the present invention can effectively recover the energy of the heat source, and because the static pressure is lower than that of the single component of Freon 22, the force of media bombardment can be reduced.

In particular, it is superior to conventional Freon 22 as a working fluid used in thermal cycles where the difference between high and low heat sources is small, such as those that utilize ocean temperature differences, and it can be used as a working fluid for nine-cycle cycles. can.

[Brief explanation of the drawing]

FIG. 1 shows a mixture system of Freon 22/Fron 152, which is the working fluid for the racin cycle of the present invention.
152 composition 10% Z-H diagram, Figure 2 is a systematic diagram of the Run Cycle, and Figure 3 is the R- s
@This is the diagram filled in above. 1... Expansion device 2... Condensing device 3... Pump 4... Steam generator (and above) Figure 2 Δ Figure 3 Entropy procedure amendment (Restraint 1, Incident indication 1982 special Permit No. 54642 2 Invention o
Name: Cow 5. ．． A. Working fluid 3. Person making the correction 4. Agent 1O Tairaheiwa Building, 2 Hirano-cho, Higashi-ku, Osaka City, main phone number 06203.
~0941 (Representative) (6521) Patent Attorney Eiji Saegusa 5. Date of amendment order Voluntary 6. No number of inventions increased by the amendment Contents of the amendment 1 [in the 16th line of page 2 of the specification] Belongs to -25℃~10
0℃" is deleted. 2. Change “variable efficiency” in the second line of page 4 of the specification to “conversion efficiency”
I am corrected. 3 “Ri00 Difluoro0 Metashi” on page 4, line 7 of the specification
``re00 difluoro0 methane and diflu state,
” to be deleted. 5 In the description in Table 1 on page 9 of the specification, in the second line of the left column, "
)0C22/F0:J152-” to “Freon22/F00
152”. 6 Correct figures 1 to 3 according to the attached drawings O (and above) 20 A 3rd figure engineer 2-to-Dhi 9 Procedural amendment (voluntary) March 2-y, 1988, Incident Indication of 1981 Patent axis No. 54642 2, Name of the invention Working fluid for Rankine cycle 3, Relationship with the person making the amendment Patent applicant Zan Hankyu Building 4, 1-12-39 Umeda, Kita-ku, Osaka City, Amendment Date of order 6, Contents of amendment (11 Specification, page 3, line 4

Claims (1)

[Claims] CI> Ri(]] Owl; A dynamic ablation fluid for run+on cycles characterized by mixing difluoroethane with fluoro-methane. (2) RiOO difluoro-methane 60-95 heavy rut attack Reach