Method for preparing alkali by ammonia-alkali process without generating ammonia distillation waste liquid

Abstract

The invention discloses a method for preparing alkali by using an ammonia-alkali method without generating ammonia distillation waste liquid, which comprises the following steps: preparing refined salt water from a solid material containing sodium salt, preparing sodium carbonate by using the ammonia-alkali method, crystallizing and separating ammonium chloride in alkali-making mother liquor, and reacting the obtained ammonium chloride crystal with quick lime or lime milk to regenerate and recover NH3. According to the invention, recycling of NH3 in the alkali production process is realized, generation of ammonia distillation waste liquid is avoided, a calcium chloride product is obtained, and the ammonium chloride crystallization mother liquor is returned to the refined brine production process for recycling, so that the utilization rate of sodium chloride in the alkali production process is greatly improved, and the production cost is reduced. Newly-added equipment needed for transformation of a traditional ammonia-alkali process alkali production line is few, the transformation cost is low, and the transformed alkali production process is clean, environmentally friendly, economical and efficient.

Description

Technical Field

[0001] The invention relates to a soda ash production process, in particular to an ammonia-soda process for producing soda ash without generating ammonia evaporation waste liquid, and belongs to the field of inorganic chemical industry and environmental protection. Background Art

[0002] Sodium carbonate is also called soda ash, and its molecular formula is: Na 2 CO 3 According to chemical theory, sodium carbonate is not an "alkali" but a salt. However, because it exhibits many characteristics of an alkali, it is usually called an alkali in industry. Soda ash is the product with the largest output in the basic chemical industry and is a basic industrial raw material with a wide range of uses.

[0003] Humans have been using alkali in their daily lives for thousands of years, and the earliest ones were obtained from wood ash and natural soda. The artificial alkali industry originated in the middle of the 18th century, and it has been more than 200 years. At present, about 27% of the global soda ash production is produced by natural soda minerals, and the rest is synthetic soda ash. A large part of the synthetic soda ash is obtained by the ammonia-soda process.

[0004] The inventor of the ammonia-soda process for producing soda ash was the Belgian Solvay, so it is also called the Solvay process. It uses salt (sodium chloride) as the raw material. The salt is first dissolved in water to produce ammonia brine, and then the CO generated by burning lime is introduced into the ammonia brine. 2 Sodium bicarbonate precipitate is generated, and the NaHCO obtained by filtration 3 Solid and alkali mother liquor. NaHCO 3 The mother liquor contains NH 4 + 、Na + , Cl - , HCO 3 - Plasma contains 1.1-1.2 mol / L of free ammonia, 3.5-3.51 mol / L of fixed ammonia, and 4.51-4.52 mol / L of total chlorine. The mother liquor of alkali production is sent to the ammonia evaporation tower, where excess lime milk is added and heated to near boiling to decompose the ammonium chloride therein. The ammonia produced by the decomposition is collected and returned to the alkali production process for recycling:

[0005] NaCl + NH 3 + H 2 O + CO 2 = NH 4 Cl + NaHCO 3 ↓ (1)

[0006] 2NaHCO 3 =Δ= Na 2CO 3 + H 2 O + CO 2 ↑ (2)

[0007] CaCO 3 =Δ= CaO + CO 2 ↑ (3)

[0008] CaO + H 2 O = Ca(OH) 2 (4)

[0009] 2NH 4 Cl + Ca(OH) 2 = CaCl 2 + NH 3 ↑ + H 2 O (5)

[0010] The Solvay process is widely used in Europe and even the world for its advantages such as easy raw material sources, simple varieties, low cost, pure quality, and suitability for large-scale continuous production. However, the Solvay process also has some defects, such as low salt utilization rate of only about 75%; difficult to handle ammonia waste liquid, 8 to 10 m3 of waste liquid is used to produce 1 ton of soda ash. 3 Waste liquid discharge, silting up rivers and harbors, polluting water bodies, and harming aquatic life. In this regard, people have conducted a lot of research, which mainly focuses on the harmless treatment of ammonia evaporation waste liquid, ignoring the transformation of the ammonia-soda process.

[0011] As we all know, ammonia waste liquid is a high pH industrial waste liquid containing calcium chloride and sodium chloride. Although it contains a large amount of calcium chloride and sodium chloride, calcium chloride and sodium chloride are both cheap inorganic salts. There is no economic benefit in separating and recovering calcium chloride and sodium chloride from ammonia waste liquid. Therefore, many alkali-making enterprises have to store ammonia waste liquid to form artificial salt lakes. If the traditional ammonia-soda alkali production process can be transformed so that it does not produce ammonia waste liquid, the economic and environmental benefits of the process will be significantly improved. Summary of the invention

[0012] In view of the defects of the traditional ammonia-soda process for alkali production, the present invention aims to provide an ammonia-soda process for alkali production without generating ammonia evaporation waste liquid. The method comprises firstly separating the ammonium chloride crystals in the alkali production mother liquor, and then reacting the obtained ammonium chloride crystals with lime milk or quicklime powder to regenerate NH 3 , in the realization of NH 3 The recycling process in the alkali production process avoids the generation of ammonia evaporation waste liquid, and the transformation process requires less new equipment and low transformation costs, which is suitable for the technical transformation of traditional production lines for ammonia-soda alkali production.

[0013] In order to achieve the above technical objectives, the present invention provides an ammonia-soda process for producing alkali without producing ammonia evaporation waste liquid, comprising the following steps:

[0014] 1) preparing refined sodium chloride from a solid material containing sodium salt, wherein the refined sodium chloride is dissolved in water to obtain refined brine;

[0015] The sodium salt in the sodium salt-containing solid material is sodium chloride or a combination of sodium chloride and at least one of sodium sulfate, ammonium sulfate, sodium nitrate and ammonium nitrate;

[0016] 2) The refined brine is filled with NH 3 Ammonia brine is obtained, and then CO is introduced 2 Sodium bicarbonate precipitate is generated, which is filtered and washed to obtain NaHCO 3 solid and alkali-making mother liquor containing ammonium chloride; the NaHCO 3 The solid is calcined to obtain soda ash;

[0017] 3) The alkali-making mother liquor containing ammonium chloride is crystallized and separated from the ammonium chloride by cold or hot method to obtain ammonium chloride crystals and ammonium chloride crystallization mother liquor; wherein the ammonium chloride crystallization mother liquor is returned to the step of preparing refined brine for recycling;

[0018] 4) Regenerate ammonium chloride crystals and quicklime by pyrolysis to recover NH 3 , and at the same time obtain calcium chloride product;

[0019] or;

[0020] Ammonium chloride crystals and lime milk are added to calcium chloride solution to react and regenerate NH 3 , and at the same time obtain calcium chloride product;

[0021] The NH 3 Return to step 2 for recycling.

[0022] The key to the technical solution of the present invention is to improve the Solvay alkali process, separate the ammonium chloride crystals in the alkali mother liquor, and then react the obtained ammonium chloride crystals with quicklime or lime milk to regenerate NH 3 , thus avoiding the generation of ammonia waste liquid in the traditional Solvay alkali process. At the same time, the present invention combines the process of refining sodium chloride from solid materials containing sodium salts, and uses the obtained sodium chloride as the source of sodium chloride in the Solvay alkali process, thus achieving the regeneration of NH 3 The ammonium chloride product can be obtained by recycling, and the ammonium chloride crystallization mother liquor can be recycled as a refined brine preparation process, thereby improving the utilization rate of sodium chloride.

[0023] As a preferred solution, when the sodium salt in the sodium salt-containing solid material is sodium chloride, water washing is used to purify the sodium chloride; as is well known, the essence of alkali production is to convert sodium chloride into sodium carbonate. Therefore, before preparing refined brine from the sodium-containing solid material, refined sodium chloride must be prepared first.

[0024] As a preferred solution, when the sodium salt in the sodium salt-containing solid material is a combination of sodium chloride and at least one of sodium sulfate, ammonium sulfate, sodium nitrate and ammonium nitrate, ammonium chloride is used as a transformation agent for transformation refining.

[0025] As a preferred solution, the transformation refining is as follows: adding water to dissolve the solid material containing sodium salt to form a nearly saturated salt solution or a saturated salt solution, adding ammonium chloride to the nearly saturated salt solution or the saturated salt solution under heating and stirring, and dissolving the ammonium chloride until it reaches or approaches saturation, using Cl - The common ion effect of ions forces Na + The ions are converted into NaCl, which is selectively crystallized and separated by filtration to obtain sodium chloride crystals and a salting-out liquid. The sodium chloride crystals are washed and filtered to obtain refined sodium chloride. The salting-out liquid is cooled and crystallized to obtain ammonium chloride crystals, which are filtered and separated to obtain ammonium chloride crystals and an ammonium chloride crystallization mother liquor. The ammonium chloride crystals are returned to the salting-out step for recycling, and the ammonium chloride crystallization mother liquor is returned to the sodium salt-containing solid material dissolution step for continued use until it has a significant inhibitory effect on the dissolution of the sodium salt-containing solid material, and the circuit is opened for comprehensive recovery. The amount of ammonium chloride added is 1 to 3 times the amount required to dissolve in the obtained nearly saturated salt solution or saturated salt solution to reach saturation.

[0026] The basic principle of preparing refined sodium chloride by transforming solid materials containing sodium salts with ammonium chloride is:

[0027] 2NH 4 Cl(excess)+Na 2 SO 4 =Δ=2NaCl↓+(NH 4 ) 2 SO 4 (6)

[0028] NH 4 Cl(excess)+NaNO 3 =Δ=NaCl↓+NH 4 NO 3 (7)

[0029] In the process of transformation refining adopted by the present invention, ammonium chloride can be used as a transformation agent and a salting-out agent at the same time to indirectly recrystallize the solid material containing sodium salt, and the added ammonium chloride can be separated from other by-products by utilizing the difference in solubility to realize recycling.

[0030] As a preferred solution, when the sodium salt-containing solid material contains organic impurities and / or other inorganic impurities, it is necessary to perform impurity removal pretreatment before adding ammonium chloride, and the impurity removal pretreatment includes at least one of the following methods:

[0031] When the solid material containing sodium salt contains organic impurities, the solid material containing sodium salt is subjected to pyrolysis treatment or oxidation treatment;

[0032] When the sodium salt-containing solid material contains insoluble inorganic impurities, filtering the nearly saturated solution or saturated solution formed by dissolving the sodium salt-containing solid material;

[0033] When the sodium salt-containing solid material contains water-soluble inorganic impurities, the nearly saturated solution or saturated solution formed by dissolving the sodium salt-containing solid material is subjected to anion impurity removal treatment and cationic impurity removal treatment: the anion impurity removal treatment process is: adding iron salt and / or aluminum salt, and adjusting the pH of the solution system to 3.5-6.5, stirring for 0.5-1.5h, and removing anion impurities including phosphate and silicate; the cationic impurity removal treatment process is: using lime-soda method to remove Mg 2+ , Fe 3+ , Mn 2+ 、Zn 2+ and Cu 2+ The iron salt and / or aluminum salt comprises at least one of ferric sulfate, aluminum sulfate, ferric nitrate and aluminum nitrate.

[0034] As a preferred solution, the dissolution temperature of the solid material containing sodium salt is 25-75°C, and the temperature for selective crystallization of sodium chloride is 65-115°C. As the temperature rises, the solubility of ammonium chloride increases significantly, which is much greater than that of sodium chloride, and the higher the temperature, the greater the difference in solubility between the two. Therefore, adding excess ammonium chloride within the temperature range selected by the present invention can utilize Cl - The common ion effect produced by ions forces the Na + The ions are converted into NaCl and selectively crystallized.

[0035] As a preferred solution, the regeneration recovery NH 3 The process is as follows: ammonium chloride crystals are mixed with quicklime powder and calcined to prepare NH 3 , and produce anhydrous calcium chloride as a by-product;

[0036] or,

[0037] By NH 4 Cl and Ca(OH) 2 The ammonium chloride crystals and lime milk are stirred and added to the NH 4In a calcium chloride solution with a Cl concentration of ≥5wt.% and a temperature of ≥105°C, it is reacted rapidly at a temperature of 105-145°C. The NH 3 Rapidly and completely evaporate, the overflowed reaction slurry is filtered while hot to remove insoluble impurities, and the filtrate is directly returned to the reaction bottom liquid for recycling or the filtrate is diluted with water to control CaCl 2 The concentration is 20-45wt.%, cooling crystallization, using Cl - The common ion effect produced forces the ammonium chloride to be deeply crystallized and precipitated, and the ammonium chloride crystals or mixed crystals of ammonium chloride and calcium chloride and their crystallization mother liquor are filtered out. The obtained crystals are returned to the ammonia distillation process for recycling, so that the effective utilization rate of ammonium chloride is maximized, and the crystallization mother liquor is further processed to produce calcium chloride products.

[0038] It must be pointed out that the process of adding ammonium chloride crystals and lime milk to a calcium chloride solution at a temperature of 105-145°C to produce ammonia is essentially different from the traditional process of directly adding lime milk to the mother liquor of alkali production to evaporate ammonia. 2 The contents of NaCl in the former are only 90-120 g / L and 40-50 g / L respectively. Under negative pressure, the highest temperature of the waste liquid in the later stage of the operation is only 95-105°C, while the evaporation rate of ammonia in the waste liquid increases with the increase of temperature. Therefore, during the reaction, the NH 3 can volatilize quickly, while the latter NH 3 The volatilization of NH 3 With H 2 O can form hydrogen bonds, resulting in NH 3 It is very difficult to completely volatilize NH, especially in the later stage of ammonia evaporation, which seriously restricts the operating efficiency of the ammonia evaporation tower. However, in a high-concentration calcium chloride solution with a temperature of 105-145°C, the violent movement of molecules prevents NH 3 With H 2 O. Although the temperature of ammonia evaporation in the former is higher than that in the latter, its energy consumption is much lower than that in the latter, because only a high concentration of calcium chloride solution can raise its temperature to 105-145°C, and a high concentration of calcium chloride solution has strong water absorption, and it is difficult to evaporate the water in the high concentration of calcium chloride solution. Therefore, to regenerate the same mass of ammonia, the amount of water evaporated in the former is much smaller than that in the latter, and the corresponding energy consumption will naturally be reduced. In addition, the former speeds up the reaction of lime and ammonium chloride by increasing the reaction temperature of the solution and increasing the concentration of ammonium chloride in the solution, and forces the NH 3 Rapid evaporation, after the reaction is completed, the filter residue obtained by filtration is mainly the insoluble impurities brought in by lime. The effective utilization rate of lime is high, while the latter relies on adding excess lime to force NH3 The lime used in the former is not only used to evaporate ammonia to form calcium chloride, but also to remove carbonate ions to form calcium carbonate precipitation. Therefore, for the same amount of ammonia evaporated, the latter consumes more lime.

[0039] As a preferred solution, the ammonium chloride crystals and quicklime powder are added according to a chemical reaction stoichiometric ratio.

[0040] As a preferred solution, the solid-to-liquid ratio of the total mass of the ammonium chloride crystals and the lime milk to the calcium chloride solution is 1:(0.5-10) g / mL.

[0041] As a preferred solution, the calcium chloride product is calcium chloride dihydrate or anhydrous calcium chloride or liquid calcium chloride.

[0042] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0043] (1) The present invention uses solid materials containing sodium salt to prepare refined brine, which not only broadens the source of raw materials for alkali production, but also reduces or avoids the interference of impurities such as calcium, magnesium and sulfate on the alkali production process.

[0044] (2) The present invention first separates the ammonium chloride crystals in the alkali production mother liquor, and then reacts the obtained ammonium chloride crystals with lime or lime milk to regenerate NH 3 At the same time, the process of refining sodium chloride from solid materials containing sodium salt is combined to achieve NH 3 In the recycling process of the alkali production process, the generation of ammonia evaporation waste liquid is avoided, and calcium chloride products are obtained. At the same time, the obtained ammonium chloride crystallization mother liquor is returned to the refined brine preparation process for recycling, which greatly improves the utilization rate of sodium chloride.

[0045] (3) The present invention uses calcium chloride solution as ammonium chloride to react with lime milk to regenerate NH 3 The reaction medium makes full use of the existing equipment of the current production line of ammonia-soda alkali production, greatly reducing the cost of transforming the traditional alkali production process. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with examples. The following examples are intended to illustrate the present invention rather than to further limit the present invention.

[0047] Example 1

[0048] First, the refined industrial salt obtained by washing the crude brine was dissolved in water to prepare a refined brine with a NaCl concentration of 312.5 g / L. The refined brine was ammonia-filled to make NH 3 The molar ratio of NaCl to CO is 1.14:1 to obtain ammonia brine, and then CO is introduced into the ammonia brine. 2 , keep CO in solution 2The concentration of sodium chloride is 35-38 g / L, so that sodium chloride is converted into sodium bicarbonate and precipitated, and NaHCO is obtained by filtration. 3 Solid and alkali mother liquor, NaHCO 3 The solid was calcined at 250°C for 0.5h to obtain first-class industrial sodium carbonate with a purity of 98.8%.

[0049] The obtained alkali mother liquor is first added with refined industrial salt to raise the NaCl concentration to 240g / L, and then cooled to 10℃ to force the NH 4 Cl crystals are precipitated, and ammonium chloride crystals and ammonium chloride crystal mother liquor are obtained by filtration. The ammonium chloride crystal mother liquor is returned to the refined brine preparation process for recycling. The utilization rate of sodium chloride in the process reaches 98.03%.

[0050] The obtained ammonium chloride crystals were washed with saturated ammonium chloride solution, filtered, dried and ground, and then NH 4 Cl reacts stoichiometrically with CaO. Ammonium chloride powder and quicklime powder with a CaO content of 91.27 wt% at -600 mesh are slowly mixed evenly under air-tight conditions. The mixture is then roasted in a kiln at 350-450°C for 1.5 hours. The roasting flue gas is collected and returned to make ammonia brine, thereby realizing the recycling of ammonia in the alkali production process.

[0051] Example 2

[0052] The first mechanical mining contains 96.01wt% NaCl and NaSO 4 3.11wt%, CaCl 2 0.59wt%,MgCl 2 0.28wt% rock salt is used as a raw material to prepare refined sodium chloride: rock salt is added with water, stirred and dissolved, and the temperature is raised to prepare a saturated NaCl solution at 55°C, and then aluminum chloride solution is added at 3 times the stoichiometric amount of aluminum phosphate to form, the solution pH is adjusted to 4.5, stirred at a constant temperature for 1h, and anionic impurities such as phosphate and silicate are removed by filtration, and then lime milk-sodium carbonate slurry is added to the filtrate, the pH is adjusted to 10.7, stirred at a constant temperature for 0.5h, and cationic impurities such as calcium and magnesium are removed by filtration, and then the purified solution is heated and stirred, and chloride is slowly added to the solution at 1.6 times the solubility of ammonium chloride at 55°C. The ammonium crystals are used as the salting-out agent, and the solution temperature is heated and stirred until it rises to 95°C. After confirming that the ammonium chloride is completely dissolved, the sodium chloride crystals and the salting-out liquid are filtered while hot and kept warm to obtain the sodium chloride crystals and the salting-out liquid. The sodium chloride crystals are then washed, filtered and dried to obtain the refined sodium chloride with a purity of 99.8% (the contents of Ca and Mg are both less than 0.01%). The obtained salting-out liquid is cooled to precipitate ammonium chloride, which is filtered to obtain the ammonium chloride crystals and the crystallized liquid. The ammonium chloride crystals are returned to continue to be used as the salting-out agent, and the ammonium chloride crystallized liquid is directly returned to the rock salt dissolution process for continued use, or after adding calcium chloride for denitration, it is returned to the rock salt dissolution process for continued use.

[0053] The obtained refined sodium chloride is used as a raw material to produce sodium carbonate by adopting the improved process of ammonia-soda method: 500g of refined sodium chloride is dissolved in water to prepare a refined brine with a NaCl concentration of 312.5g / L, and the refined brine is charged with ammonia to obtain ammonia brine, wherein the refined brine and ammonia gas are added according to the stoichiometric ratio, and then CO is introduced into the ammonia brine according to the stoichiometric ratio 2 Sodium bicarbonate precipitate is generated and filtered to obtain NaHCO 3 Solid and alkali mother liquor, NaHCO 3 The solid was calcined at 205°C for 1 hour to obtain an industrial high-quality sodium carbonate product with a purity of 99.2%.

[0054] The obtained alkali-making mother liquor is heated to 65°C and evaporated under negative pressure for 0.5h to convert the residual ammonium bicarbonate and sodium bicarbonate therein into ammonium carbonate and sodium carbonate, and then refined sodium chloride is added to increase the concentration of NaCl to 220g / L, and the mixture is cooled to allow the ammonium chloride therein to selectively crystallize and precipitate, and the ammonium chloride crystals and their crystallization mother liquor are filtered out, and the crystallization mother liquor is returned to the refined brine preparation process for recycling, and the obtained ammonium chloride crystals are washed with a saturated ammonium chloride solution and then heated to NH 4 Cl and Ca(OH) 2 The molar ratio is 2:1. Stir and slowly add it into the NH 4 Cl concentration is 10wt%, CaCl 2 In the ammonia evaporation tower with a reaction bottom liquid of 35wt% and a temperature of 108℃, the solid-liquid ratio of the reaction slurry is controlled to be 1:3.5g / mL, so that it reacts quickly at a temperature of 108-135℃. The residence time of the material in the reactor is less than 1h. The NH 3 The collected solution is used to make ammoniacal brine. The overflowed reaction slurry is filtered while hot to remove insoluble impurities. The filtrate is diluted with water to a CaCl 2 The content is 38.5wt%, and the ammonium chloride is cooled to 10°C to crystallize. The ammonium chloride crystals and calcium chloride solution are filtered. The calcium chloride solution is further evaporated and concentrated to obtain high-quality calcium chloride dihydrate. The utilization rate of sodium chloride in the alkali production process is 98.42%.

[0055] Comparative Example 1

[0056] Take 1000g of refined industrial salt and dissolve it in water to prepare a refined brine with a NaCl concentration of 310.6g / L. The refined brine is ammonia-filled to make NH 3 The molar ratio of NaCl to CO is 1.15:1 to obtain ammonia brine, and then CO is introduced into the ammonia brine. 2 , keep CO in solution 2 The concentration of sodium chloride is 37-39 g / L, which converts sodium chloride into sodium bicarbonate and precipitates it. Then, NaHCO is obtained by filtration. 3 Solid and alkali mother liquor, NaHCO3 The solid was calcined at 250°C for 0.5h to obtain first-class industrial sodium carbonate with a purity of 98.9%.

[0057] The obtained alkali-making mother liquor was added with excess lime milk and ammonia was evaporated under negative pressure at 85-95°C for 2.5 hours to obtain CaCl 2 115.2g / L, 6.36L of ammonia waste liquid with NaCl 40.5g / L, the utilization rate of sodium chloride in the alkali production process is 74.01%, and the volatilized NH 3 The collected water is returned to prepare ammonia brine.

Claims

1. A method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid, characterized in that: The following steps are involved: 1) preparing refined sodium chloride from a solid material containing sodium salt, wherein the refined sodium chloride is dissolved in water to obtain refined brine; The sodium salt in the sodium salt-containing solid material is sodium chloride or a combination of sodium chloride and at least one of sodium sulfate, ammonium sulfate, sodium nitrate and ammonium nitrate; 2) NH3 is added to the refined brine to obtain ammoniacal brine, and then CO2 is introduced to generate sodium bicarbonate precipitation, which is filtered and washed to obtain NaHCO3 solid and alkali-making mother liquor containing ammonium chloride; the NaHCO3 solid is calcined to obtain soda ash; 3) The alkali-making mother liquor containing ammonium chloride is crystallized and separated from the ammonium chloride by cold or hot method to obtain ammonium chloride crystals and ammonium chloride crystallization mother liquor; wherein the ammonium chloride crystallization mother liquor is returned to the step of preparing refined brine for recycling; 4) Regenerating ammonium chloride crystals and quicklime by pyrolysis to recover NH3 and obtain calcium chloride product; or; Adding ammonium chloride crystals and lime milk to a calcium chloride solution for reaction, regenerating and recovering NH3, and obtaining a calcium chloride product at the same time; The NH3 is returned to step 2 for recycling.

2. The method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid according to claim 1, characterized in that: When the sodium salt in the sodium salt-containing solid material is sodium chloride, the sodium chloride is refined by washing with water; When the sodium salt in the sodium salt-containing solid material is a combination of sodium chloride and at least one of sodium sulfate, ammonium sulfate, sodium nitrate and ammonium nitrate, ammonium chloride is used as a transformation agent for transformation refining.

3. The method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid according to claim 2, characterized in that: The transformation refining comprises: adding water to dissolve the solid material containing sodium salt to form a nearly saturated salt solution or a saturated salt solution, adding ammonium chloride to the nearly saturated salt solution or the saturated salt solution under heating and stirring, and waiting for the ammonium chloride to dissolve until it reaches or approaches saturation, using Cl - The common ion effect of ions forces Na + The ions are converted into NaCl, which is selectively crystallized and separated by filtration to obtain sodium chloride crystals and a salting-out liquid. The sodium chloride crystals are washed and filtered to obtain refined sodium chloride. The salting-out liquid is cooled and crystallized to obtain ammonium chloride crystals, which are filtered and separated to obtain ammonium chloride crystals and an ammonium chloride crystallization mother liquor. The ammonium chloride crystals are returned to the salting-out step for recycling, and the ammonium chloride crystallization mother liquor is returned to the sodium salt-containing solid material dissolution step for continued use until it has a significant inhibitory effect on the dissolution of the sodium salt-containing solid material, and the circuit is opened for comprehensive recovery. The amount of ammonium chloride added is 1 to 3 times the amount required to dissolve in the obtained nearly saturated salt solution or saturated salt solution to reach saturation.

4. The method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid according to claim 3, characterized in that: The dissolution temperature of the solid material containing sodium salt is 25-75°C, and the temperature for selective crystallization of sodium chloride is 65-115°C.

5. The method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid according to claim 1, characterized in that: The process of regenerating and recovering NH3 is as follows: ammonium chloride crystals are mixed with quicklime powder and calcined to prepare NH3, and anhydrous calcium chloride is produced as a by-product; or, According to the molar ratio of NH4Cl to Ca(OH)2≥2:1, ammonium chloride crystals and lime milk are stirred and added into a calcium chloride solution with a concentration of NH4Cl≥5wt.% and a temperature≥105°C as the reaction base liquid, so that it reacts rapidly at a temperature of 105-145°C, and the NH3 produced by the reaction evaporates quickly and completely. The overflowing reaction slurry is filtered while hot to remove insoluble impurities, and the filtrate is directly returned to the reaction base liquid for recycling or the filtrate is diluted with water to control the CaCl2 concentration to 20-45wt.%, and then cooled and crystallized. Cl - The common ion effect produced forces the ammonium chloride to be deeply crystallized and precipitated, and the ammonium chloride crystals or mixed crystals of ammonium chloride and calcium chloride and their crystallization mother liquor are filtered out. The obtained crystals are returned to the ammonia distillation process for recycling, so that the effective utilization rate of ammonium chloride is maximized, and the crystallization mother liquor is further processed to produce calcium chloride products.

6. The method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid according to claim 5, characterized in that: The total mass of the ammonium chloride crystals, the lime milk and the solid-to-liquid ratio of the calcium chloride solution is 1: (0.5-10) g / mL.

7. The method for producing alkali by an ammonia-soda process without producing ammonia evaporation waste liquid according to any one of claims 1 to 6, characterized in that: The calcium chloride product is calcium chloride dihydrate or anhydrous calcium chloride or liquid calcium chloride.