JPS5821554B2 - distillation equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a distillation apparatus using solar heat to obtain fresh water from seawater or brine.

Conventionally, various types of distillation apparatuses that utilize solar heat have been known.

In particular, for seawater or brine distillation equipment, the most common method is to introduce hot water from a collector to absorb solar energy into a multi-stage flash method or multiple effect method to heat and distill seawater. Met.

However, according to this method, the amount of heating per 1 kg of distilled water is large, such as the multi-stage flash method or the multiple effect method, and the area of the collector needs to be large, so it is not necessarily possible to obtain distilled water economically. Ta.

The present invention eliminates these drawbacks and provides a distillation apparatus that obtains distilled water using a compact apparatus with high thermal efficiency.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

Reference numeral 1 denotes an evaporator, which has an upper water chamber 2, a lower brine reservoir 3, and a hard tube type evaporative heat transfer tube 4 that communicates the two.A distribution nozzle 5 is provided above the evaporative heat transfer tube 4, and a heating chamber 6. A production water reservoir 7 is provided on the lower side of the lower brine reservoir 3, and an evaporator gas-liquid separator 9 having a demister 8 is further provided on the upper side of the lower brine reservoir 3.

10 is suction port 11, diffuser 12, impeller 1
3, etc., a suction port 11 serving as a vapor inlet communicates with the gas-liquid separator 9 via a conduit 14, and a diffuser 1 serving as a vapor outlet.
2 communicates with the heating chamber 6 via a conduit 15.

A gas turbine 17 is provided on a rotating shaft 16 common to the impeller 13, and the rotating shaft 16 is supported by a bearing 18.

Reference numeral 19 denotes a shell-and-tube type, one-plate type, or multi-stage flash type three-component heat exchanger, into which raw water (seawater, etc.) 20 is supplied via a conduit 22 by a raw water supply pump 21, and the conduit 22 has: A conduit 24 from a chemical injection pump 23 for scale suppression is connected.

The raw water 20 from the three-component heat exchanger 19 passes through a conduit 27 to a vent condenser 28 (separating non-condensable gases contained in the raw water);
A conduit 29 from 8 communicates with the upper water chamber 2 via a conduit 31 having a feed water heater 30, which is an example of a heating device for feed raw water, in the middle.

The lower brine reservoir 3 communicates via a conduit 32 with a brine discharge and circulation pump 33 and further communicates with the conduit 31 via a conduit 34.

At the upper end of the conduit 34 is a liquid level adjustment valve 3 which is controlled by detecting the amount of brine (condensed water) 35 in the lower brine reservoir 3.
6 is provided, and further downstream a flow rate regulating valve 31 is provided.

A conduit 38 is branched from between the two valves 36 and 37, and the brine 35 is discharged through the three-component heat exchanger 19.

The product water reservoir 7 is configured to communicate with a distilled water pump 41 via a conduit 40, and further to be sent to a three-component heat exchanger 19 via a conduit 42, through which product water 43 is obtained. It is.

The heating chamber 6 is provided with an opening 44, and this opening 4
4 communicates with the vent condenser 28 via a conduit 45.

46 indicates a vent pipe.

The gas turbine 17 is a vapor compressor and serves as the prime mover of the machine 10, and is driven by refrigerant gas such as fluorocarbon gas flowing through a closed circuit 47.

The closed circuit 47 is provided with, in order from the exit side of the gas turbine 17, a refrigerant gas condensing condenser 49 through which the cooling water 48 is passed, a refrigerant liquid condensation heat pump 50, and a heat exchanger 51.

52 is a solar heat collector (heat collector), and in the closed circuit 53 of the solar heat absorption system, there is an expansion tank 54 which also serves as a heat storage for absorbing the amount of expansion and contraction of circulating water due to changes in the amount of solar heat radiation. and a hot water circulation pump 55,
Then, it passes through the heat exchanger 51.

Reference numeral 56 designates a supply conduit that communicates the upper end of the heat exchanger 51 and the feed water heater 30 to the closed circuit 53, and 57 represents a discharge conduit that communicates the lower end of the feed water heater 30 and the heat exchanger 51.

The functions of this device will be explained below.

The raw water 20 that has been sucked up is supplied to a conduit 22 by a raw water supply pump 21, and a scale inhibitor solution is injected from a scale inhibitor injection pump 23 in the middle of this conduit 22, and then
The brine 3 from the evaporator 1 enters the three-component heat exchanger 19.
5 and produced water 43 to be heated.

The raw water 20 then passes through a vent condenser 28 separating non-condensable gases and, during its flow through conduits 29.31, is heated by solar heat in a feed water heater 30 before being heated in the upper water chamber of the evaporator 1. Enter 2.

The inside of the evaporator 1 is equipped with a plurality of hard tube type evaporative heat transfer tubes 4, and a distribution nozzle 5 is installed above each evaporative heat transfer tube 4 to uniformly distribute the raw water 20. It flows down the inner wall of the tubular evaporation heat transfer tube in the form of a thin film and falls into the lower brine reservoir 3.

When the evaporator 1 is started, the hot water heated by the solar collector 52 is passed through the feed water heater 30 through the supply conduit 56 and the discharge conduit 57 to heat the raw water 20, and is flash-evaporated by the distribution nozzle 5.

The steam generated by flashing passes from the lower brine reservoir 3 through a demister 8 installed in a gas-liquid separator 9, and is separated into gas and liquid by the demister 8, and only the steam and non-condensable gas are passed through the conduit 14. It is sucked into the suction port 11 of the vapor compressor 10.

At this time, in the closed circuit 47, the refrigerant liquid condensed by the condenser 49 is circulated by the condenser heat pump 50, enters the heat exchanger 51, becomes high temperature and high pressure gas, enters the turbine 17 again, and performs work.

The turbine 17 is operated by the refrigerant vapor which has become high temperature and high pressure due to solar heat, and the vapor compressor 10 is driven.

Therefore, the vapor generated by the evaporator 1 is transferred to the vapor compressor 1
The vapor is adiabatically compressed by the vaporizer 1 and becomes vapor at a higher temperature and pressure than the vapor evaporated in the evaporator 1, and is introduced into the heating chamber 6.

This high-pressure, high-temperature steam is used as heated steam in the evaporator 1 to heat the raw water 20 and its brine flowing along the inner wall of the heat exchanger tube in the heating chamber 6, and evaporates a portion of it to form steam.

The heated steam is condensed and becomes distilled water, that is, produced water 43.

The steam and unevaporated residual brine pass through the interior of the evaporative heat transfer tubes 4 and enter the lower brine reservoir 3.

Then, as described above, the steam flows into the vapor compressor 10 through the gas-liquid separator 9 and the like.

The brine 35 in the lower brine reservoir 3 is supplied to the brine pump 33.
A portion is discharged through the three-component heat exchanger 19, and the remaining portion is mixed with fresh raw water 20 through the flow rate regulating valve 37 and circulated through the conduit 31 to the evaporator 1.

At this time, the water level in the lower brine reservoir 3 is kept constant by the liquid level adjustment valve 36.

Product water 43 generated by condensation in heating chamber 6 is collected in product water reservoir 7 .

It is then discharged through conduit 40 and distilled water pump 41 and enters three-component heat exchanger 19 through conduit 42.

The produced water 43 and the aforementioned brine 35 that have entered the three-component heat exchanger 19 in this way heat the raw water 20 by heat exchange.

The non-condensable gas present in the heating chamber 6 enters the vent condenser 28 through the opening 44 and the conduit 45 and is discharged into the air via the vent pipe 46.

Both open circuits 47 and 53 may be combined into one, the heat exchanger 51 may be omitted, and refrigerant liquid may be directly circulated instead of circulating water.

As explained above, in the solar heat-utilizing distillation apparatus according to the present invention, solar thermal energy is converted into kinetic energy by a turbine to drive a vapor compressor, thereby operating a vapor compression type distillation apparatus.

A comparison of the desalination equipment using the combination of the present invention and the conventional multi-stage flash method or multi-effect method using solar heat as follows: (A) In the conventional multi-stage flash method or multi-effect method using solar heat, 1 kg of distilled water The amount of heat required for is 56K
ca1 or more.

(B) In the solar heat-utilizing steam compression distillation apparatus of the present invention, the amount of heat required for 1 kg of distilled water is approximately 25 Kcal when the turbine efficiency is 60%.

Therefore, in the present invention, the collector area can be reduced by less than half (
Distilled water can be obtained economically.

[Brief explanation of the drawing]

The drawing is a process flow sheet showing one embodiment of the present invention. 1...Evaporator, 4...Evaporation heat transfer tube, 6
... Heating chamber, 9 ... Evaporator gas-liquid separator, 10 ... Rotary vapor compressor, 11 ...
・Suction port, 12... Diffuser, 13...
... Impeller, 16 ... Rotating shaft, 17.
... Gas turbine, 19 ... Three-component heat exchanger, 20 ... Raw water, 23 ... Chemical injection pump, 30 ... Water supply Heater, 35...
...Brine, 43...Produced water, 47.53.
...Closed circuit, 49...Condenser for refrigerant gas condensation, 50...'' Refrigerant liquid condensation heat pump, 51... Heat exchanger, 52... Solar heat collector (heat collector).

Claims (1)

[Claims] 1 The steam generated from the evaporator is compressed into high-temperature, high-pressure steam using a vapor compressor, and then supplied to the evaporator as heated steam, and in the evaporator, two parts of the raw water are converted by heat exchange between the high-temperature, high-pressure steam and the raw water. In a distillation apparatus configured to evaporate water and condense heated steam, a turbine is provided which is linked to the vapor compressor, and this turbine is driven by solar thermal energy absorbed by a collector. A distillation apparatus characterized in that the distillation apparatus is configured to heat raw water before being supplied to the evaporator by a portion of the water.