CN106147724A

CN106147724A - A kind of preparation method of low temperature energy storage molten salt

Info

Publication number: CN106147724A
Application number: CN201510157892.0A
Authority: CN
Inventors: 官景栋
Original assignee: Tianjin Binhai Photo Thermal Power Generation Investment Co Ltd
Current assignee: Tianjin Binhai Photo Thermal Power Generation Investment Co Ltd
Priority date: 2015-04-06
Filing date: 2015-04-06
Publication date: 2016-11-23

Abstract

The present invention discloses the preparation method of a kind of low temperature energy storage molten salt, carries out as steps described below: step 1, selects the salt being up to state standards and purifies；Step 2, the salt purified through step 1 is carried out the mixing of different proportion, uses differential scanning calorimeter to measure fusing point the record heat accumulation energy simultaneously of different ratio salt, with determine the salt-mixture of different proportion character, at according to requirements 100～500 DEG C, determine the proportioning of salt.Compared with other fused salt, this kind of fused salt freezing point is low, the upper limit uses temperature high, when being so applied to solar light-heat power-generation industry, steam turbine can be kept to operate under peak efficiency, can be reduced to again prevent fused salt from the maintenance and management expense that freezing point state is paid occurring, be greatly saved investment and the operating cost at solar light-heat power-generation station, reduce photo-thermal power generation cost, there is extraordinary application prospect.

Description

A kind of preparation method of low temperature energy storage molten salt

Technical field

The present invention relates to the preparation method of a kind of salt, more particularly, relate to the preparation method of a kind of mental retardation energy storage molten salt.

Background technology

At present, in preparing high-purity heat-conduction energy storage molten salt field, the general method using electrolysis of preparation of fused salt, this Plant preparation method and there is shortcomings: (1) cost is high, and investment is big, and income is low；(2) the various corrosive mediums of fused salt Index severe overweight, such as chloride ion 1000ppm, sulfate 1000ppm, water-insoluble 2000ppm, calcium content 100ppm, content of magnesium 200ppm, iron content 100ppm, the corrosive medium of these severe overweights causes equipment short-term Inside it is corroded, shortens service life and the service life of fused salt itself of equipment；(3) right during fused salt uses Various metal material fused salt equipment have stronger corrosivity, substantially reduce the use cycle of metal material fused salt equipment； (4) high due to the impurity of fused salt, purity is low, causes equipment corrosion or fouling, makes heat conductivity and the heat conduction effect of fused salt Rate reduces, and fusing point raises.Therefore the service life of fused salt is typically at about 3 years；(5) because fused salt is often changed, make Short with the cycle, institute is so that cost improves, and environmental pollution is serious.Have begun in the prior art salt is carried Pure, but common purification mode often cannot realize higher purification efficiency, and the use state and the effect that are required for salt are entered Row comprehensive consideration.

Summary of the invention

It is an object of the invention to overcome the deficiencies in the prior art, it is provided that the preparation method of a kind of mental retardation energy storage molten salt, it is intended to It is capable of purification and the mix homogeneously of each component, realizes using effect and performance simultaneously.

The technical purpose of the present invention is achieved by following technical proposals:

The preparation method of a kind of mental retardation energy storage molten salt, is carried out as steps described below:

Step 1, selects the salt being up to state standards and purifies, and in purification process, carries out salt dissolving formation salt Successively carry out adsorbing by adsorbent resin after solution and carry out filter pressing with pressure filter, then after the saline solution after filter pressing is cooled down Recrystallization, finally washs the salt after recrystallization with pure water；

Step 2, carries out the mixing of different proportion by the salt purified through step 1, uses differential scanning calorimeter to measure not With proportioning salt fusing point and simultaneously record heat accumulation energy, with determine the salt-mixture of different proportion character, according to use want Ask 100～500 DEG C, determine the proportioning of salt.

In the inventive solutions, salt is selected from NaNO₃、KNO₃、NaNO₂, take 9%wt NaNO₃, 51%wt KNO₃, 40%wt NaNO₂Proportions time, relatively low 100～500 DEG C of fused salt mixt fusing point, heat accumulation cost is minimum.

Compared with other fused salt, this kind of fused salt freezing point is low, and the upper limit uses temperature high, is so applied to solar energy optical-thermal and sends out During electricity industry, steam turbine can be kept to operate under peak efficiency, can be reduced to again prevent fused salt from solidification point-like occurring The maintenance and management expense that state is paid, is greatly saved investment and the operating cost at solar light-heat power-generation station, reduces light Hot cost of electricity-generating, has extraordinary application prospect.

Detailed description of the invention

Technical scheme is further illustrated below in conjunction with specific embodiment.

Have selected for the fused salt of photo-thermal power generation industry low temperature energy storage apply have in heat transfer, heat reservoir range wide, The salt-mixture of the sodium nitrate of stable in properties, potassium nitrate and sodium nitrite.

Choose and after the salt being up to state standards dissolves respectively, form single product saline solution, adsorbed by adsorbent resin, then By pressure filter filter pressing, then recrystallization after being cooled down by list product saline solution, with pure water, single after recrystallization is savored salt Wash, the more single salt of savoring after washing is put into electric heating reacting kettle, add pure water post-heating, by electrical heating Single product saline solution in reactor is placed in crystallisation by cooling in cooler, by the single salt of savoring after crystallization by centrifuge dewatering, then Washing the single salt of savoring after dehydration with pure water, after washing, single salt of savoring is again by centrifuge dewatering, is then dried, Obtain highly purified single savoring salt.

The mixed nitrate fused salt of 18 kinds of different proportions of configuration, uses differential scanning calorimeter (DSC) to determine different ratio The fusing point of fused salt, on this basis, the specific heat of proportioning fused salt relatively low to several fusing points is measured, and carries out heat accumulation cost Analyze, finally determine, when three kinds of fused salts take 9%wt NaNO₃, 51%wt KNO₃, 40%wt NaNO₂Ratio join Than time, fused salt mixt fusing point is relatively low, and heat accumulation cost is minimum.Compared with other fused salt, this kind of fused salt freezing point is low, the upper limit Use temperature is high, when being so applied to solar light-heat power-generation industry, steam turbine can be kept to transport under peak efficiency Make, can be reduced to again prevent fused salt from the maintenance and management expense that freezing point state is paid occurring, be greatly saved solar energy The investment of photo-thermal power station and operating cost, reduce photo-thermal power generation cost, have extraordinary application prospect.

Above the present invention is done exemplary description, it should explanation, in the case of without departing from the core of the present invention, Any simple deformation, amendment or other those skilled in the art can not spend the equivalent of creative work all to fall Enter protection scope of the present invention.

Claims

1. the preparation method of a mental retardation energy storage molten salt, it is characterised in that carry out as steps described below:

The preparation method of a kind of mental retardation energy storage molten salt the most according to claim 1, it is characterised in that salt is selected from NaNO₃、KNO₃、NaNO₂。

The preparation method of a kind of mental retardation energy storage molten salt the most according to claim 1, it is characterised in that salt is selected from 9%wt NaNO₃, 51%wt KNO₃, 40%wt NaNO₂, fused salt mixt fusing point is 100～500 DEG C.