CN102092744A

CN102092744A - Method for melting fused salt with pure water

Info

Publication number: CN102092744A
Application number: CN 201010556648
Authority: CN
Inventors: 张建
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-11-23
Filing date: 2010-11-23
Publication date: 2011-06-15

Abstract

The invention discloses a method for melting fused salt with pure water, which is characterized by comprising the following steps of: (1) starting pure water circulation: firstly, adding pure water accounting for 30% of the volume of a fused salt storage tank into the fused salt storage tank, and starting a fused salt pump to ensure that the pure water inside the fused salt storage tank enters an evaporator through a fused salt furnace and returns to the interior of the fused salt storage tank so as to circulate the pure water as much as possible; and (b) heating a salt solution, continuously and slowly putting fused salt into the fused salt storage tank at the same time of starting the pure water circulation, and starting the fused salt furnace at the same time to ensure that the salt solution is subjected to circular heating by a gradient of temperature rise of 6 DEG C per hour so as to heat the salt solution, wherein when the temperature of the solution reaches 142 DEG C, the water is completely evaporated and the fused salt is in a liquid state, namely, the fused salt melting process is completed and the salt reaches a melting state. By means of the method, the fused salt melting time is short and lasts for only one day, other heating equipment are unnecessary to mount additionally, the entire fused salt melting process is stable, and the fused salt cannot be decomposed so that cost is saved; and compared with the traditional method, the method has the advantages of saving a large amount of time, omitting a large amount of equipment and reducing energy consumption.

Description

A kind of method of pure water fused salt

Technical field

The present invention relates to change in a kind of chlor-alkali industry the method for fused salt, particularly a kind of method of pure water molten-salt growth method.

Background technology

Fused salt: be a kind of mixture of being made up of three kinds of pure nitrate, it mixes the synthetic KNO that is divided in back ₃: NaNO 53%, ₂: NaNO 40%, ₃: 7%, this mixture is the white crystal that is similar to salt under the normal temperature situation, fusing point is 142 ℃, highly stable below 427 ℃, begins to have slow decomposition more than 450 ℃, therefore in use need temperature is controlled at below 450 ℃, in the time of between 350 ℃～450 ℃, its viscosity is 2.4～4.9 centipoises (because of viscosity is low, good fluidity), specific heat capacity is 1.42kJ/kg ℃ (higher because of specific heat capacity, heat load is bigger).In sum: the liquid wide ranges of this mixture, good fluidity, heat load is big, and therefore, it is widely used in the thermophore of about 400 ℃ of heating in chemical process.Therefore, all fused salt is produced solid caustic soda, i.e. molten-salt growth method solid caustic soda as thermophore heating caustic soda soln at chlor-alkali industry.But, need to use after the fusing because of fused salt is the solid that is similar to salt at normal temperatures.

In the molten-salt growth method solid potash device of chlor-alkali industry, the method for traditionization fused salt has two kinds:

1, uses the steam heating fused salt, make the fused salt fusing, this method three shortcomings are arranged, one: it is the saturation steam (saturated-steam temperature of 0.7Mpa is 164 ℃) of 0.7Mpa that the solid potash device scene of chlor-alkali industry generally can only provide pressure, fused salt need be heated to 142 ℃ of ability fusings, because heat transfer temperature difference is little, only there be 164-142=22 ℃, and be indirect heating, make the fused salt fusing, must need extremely for a long time, the general time was at 7～10 days.Its two: steam heat-exchanging equipment need to be installed.Its three: need expend a large amount of steam.

2, use the electrically heated fused salt, make the fused salt fusing, also there are three shortcomings in this method, one: the electric heater surface temperature is up to 550 ℃, and this makes the part generation pyrolytic decomposition that electric heater contacts with fused salt: (5NaNO ₂=3NaNO ₃+ Na ₂O+N ₂↑), the composition ratio in the fused salt changes, and will cause the fusing point of fused salt to raise, and heat transfer efficiency reduces.Its two: electrical heating device need to be installed.Its three: need expend a large amount of electric energy.

Summary of the invention

Purpose of the present invention is exactly at the deficiencies in the prior art, and a kind of method of pure water molten-salt growth method is provided.

For achieving the above object, the present invention adopts following technical scheme:

A kind of method of pure water molten-salt growth method is characterized in that may further comprise the steps:

A), start the pure water circulation

The pure water that in the fused salt storage tank, adds earlier fused salt storage tank volume 30%, start pump for liquid salts make in the fused salt storage tank pure water through molten salt furnace to vaporizer, return in the fused salt storage tank, make pure water row circulation to the greatest extent;

B), saline solution heating

In the fused salt storage tank, drop into simultaneously fused salt continuously, slowly at startup pure water round-robin, start molten salt furnace simultaneously, make saline solution with the intensification that circulates of 6 ℃ heating gradient per hour, make the saline solution heating, when solution temperature reaches 142 ℃, moisture content is evaporated fully and is liquid state, has promptly finished the process of changing fused salt, and salt reaches molten state.

Pure water claims pure water, deionized water again, be meant that with the water that meets drinking water sanitary standard be former water, by electrodialyzer method, ion-exchanger method, reverse osmosis method, distillation method and other suitable working methods, what make is sealed in the container, and does not contain any additive, water white transparency, water capable of direct drinking also can be called pure substance (chemically), uses in test more, again because of being to make, so claim distilled water again with methods such as distillations.The space water of selling on the market, distilled water all belongs to pure water; But pure water should be drunk less, because the inside does not have the mineral substance that too many human body needs.Pure water is easy conductive not, is isolator.To use pure water during the lead acid cell moisturizing.

The effluent quality hygienic requirements of water purifior should meet the requirement in Ministry of Health's promulgation in 1998 " reverse osmosis drinking-water treatment apparatus hygienic safety and functional evaluation regulation ".

The beneficial effect of the method for a kind of pure water molten-salt growth method of the present invention is, it is short to change the fused salt time, only need the time with method fused salt of the present invention, do not need to install in addition other heating installation, wholeization fused salt process stabilization, fused salt can not decompose, saved cost, compare with traditional method, saved a large amount of time, equipment, reduced energy consumption.

Description of drawings

Fig. 1 is the structural representation of molten-salt growth method solid potash device of the present invention;

Fig. 2 is a process flow diagram of the present invention.

The present invention is further illustrated below in conjunction with accompanying drawing for embodiment, but therefore do not limit the present invention among the described scope of embodiments.

Referring to Fig. 1, Fig. 2,1, a kind of method of pure water molten-salt growth method, it is characterized in that may further comprise the steps:

A), start the pure water circulation

In fused salt storage tank 1, add earlier a small amount of pure water, generally add the pure water of fused salt storage tank volume about 30%, start pump for liquid salts 2 make in the fused salt storage tank 1 pure water through molten salt furnace 3 to vaporizer 4, return in the fused salt storage tank 1, make pure water row circulation to the greatest extent;

B), saline solution heating

Start the pure water round-robin simultaneously in the fused salt storage tank 1 continuously, drop in proportion slowly: KNO ₃: NaNO 53%, ₂: NaNO 40%, ₃: 7%, the solid fused salt for preparing, make its continuous stirring and dissolving, start molten salt furnace 3 (the little fire operation of molten salt furnace simultaneously, by control, fire box temperature is remained on about 250 ℃), make saline solution with the intensification that circulates of 6 ℃ heating gradient per hour, make the saline solution heating, because adding in continuous circulation, the fused salt aqueous solution pines for the temperature rising, the solubleness of fused salt in water raises with water temperature, replenishes the solid fused salt gradually along with continuous circulation is heated according to the dissolving situation of fused salt again, and water is evaporated gradually, when solution temperature reaches 142 ℃, moisture content is evaporated fully and is liquid state, has promptly finished the process of changing fused salt, and salt reaches molten state.

Described embodiments of the present invention though combine accompanying drawing, those of ordinary skill in the art can make various distortion or modification within the scope of the appended claims.The technician of the industry should understand; the present invention is not restricted to the described embodiments; that describes in the foregoing description and the specification sheets just illustrates principle of the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.The claimed scope of the present invention is defined by appending claims and equivalent thereof.

Claims

1. the method for a pure water molten-salt growth method is characterized in that may further comprise the steps:

A), start the pure water circulation

The pure water that adds fused salt storage tank volume 30% earlier in fused salt storage tank (1) starts pump for liquid salts (2) and makes the middle pure water of fused salt storage tank (1) arrive vaporizer (4) through molten salt furnace (3), returns in the fused salt storage tank (1), makes pure water row circulation to the greatest extent;

B), saline solution heating

Drop into fused salt continuously, slowly in the startup pure water round-robin while (1) in the fused salt storage tank, start molten salt furnace (3) simultaneously, make saline solution with the intensification that circulates of 6 ℃ heating gradient per hour, make the saline solution heating, when solution temperature reaches 142 ℃, moisture content is evaporated fully and is liquid state, has promptly finished the process of changing fused salt, and salt reaches molten state.