萘是稠环芳烃，是有机化合物。分子式为C10H8，无色，有毒，易升华，片状晶体，有特殊气味。它是由焦化煤焦油和石油蒸馏大量生产的，主要用于邻苯二甲酸酐的合成。过去，卫生球是由萘制成的，但是由于萘的毒性，现在已禁止使用萘作为一种成分。接触萘和溶血性贫血会导致肝和神经系统损害，白内障和视网膜出血。合理预期萘是人类致癌物，可能与喉癌和结直肠癌的风险增加有关。

Naphthalene is a polycyclic aromatic hydrocarbon and an organic compound. The molecular formula is C10H8, colorless, toxic, prone to sublimation, plate-like crystals, with a special odor. It is produced in large quantities from coking coal tar and petroleum distillation, mainly used for the synthesis of phthalic anhydride. In the past, sanitary balls were made from naphthalene, but due to its toxicity, the use of naphthalene as a component is now prohibited. Exposure to naphthalene and hemolytic anemia can lead to liver and nervous system damage, cataracts, and retinal hemorrhage. Reasonable expectations suggest that naphthalene is a human carcinogen and may be associated with an increased risk of laryngeal and colorectal cancer.

生产和制备简介：

Introduction to Production and Preparation:

从石油烃类制造：催化重整油，轻循环油催化裂化，乙烯裂解副产物焦油等；

From petroleum hydrocarbon manufacturing: catalytic reforming oil, light cycle oil catalytic cracking, ethylene cracking by-product tar, etc;

与煤焦油分离，高温煤焦油中的萘约占8％-12％。将煤焦油蒸馏，将煤油切碎，并通过脱酚和脱喹啉蒸馏获得终的萘。

Separate from coal tar, naphthalene in high-temperature coal tar accounts for about 8% -12%. Distill the coal tar, cut the kerosene into small pieces, and obtain the final naphthalene through dephenolization and quinoline removal distillation.

精萘是将粗萘精制而成。

Refined naphthalene is refined from crude naphthalene.

降膜分步结晶结晶生产工艺流程由产品生产工艺系统，能量系统，氮气密封系统和计算机控制系统组成。生产过程系统将大周期用作生产周期。每个大周期包含4个小周期，每个小周期包含4至6个段。每个段包括3个步骤：结晶，部分熔融和全部熔融；

The production process of falling film fractional crystallization crystallization consists of a product production process system, an energy system, a nitrogen sealing system, and a computer control system. The production process system uses large cycles as production cycles. Each large cycle contains 4 small cycles, and each small cycle contains 4 to 6 segments. Each section includes three steps: crystallization, partial melting, and complete melting;

从工业萘装置送来的液态工业萘被送到馏出罐，当进行第四阶段结晶操作时，罐中的原料液体被送到动态结晶器收集槽

The liquid industrial naphthalene sent from the industrial naphthalene unit is sent to the distillation tank. When the fourth stage crystallization operation is carried out, the raw material liquid in the tank is sent to the dynamic crystallizer collection tank

未结晶的萘油和汗液放入纯度较低的分馏罐中，并且在五阶段中可以将全部熔体用作原料。可以根据预定程序在六个阶段的晶体精制之后获得精致的萘。为了提高萘的萃取率，可以将富含硫茚的馏分送入静态结晶器进行处理。从静态结晶器中获得的产品返回到动态结晶系统的相应分馏罐中，残留液体可以作为减水剂出售。由于该设备同时使用动态和静态结晶器，因此不仅可以确保更高的萘回收率，而且可以减少能耗。

Uncrystallized naphthalene oil and sweat are placed in a lower purity fractionation tank, and in the fifth stage, all the melt can be used as raw materials. Refined naphthalene can be obtained after six stages of crystal refinement according to the predetermined program. In order to improve the extraction rate of naphthalene, the fraction rich in sulfur indene can be sent to a static crystallizer for processing. The product obtained from the static crystallizer is returned to the corresponding distillation tank of the dynamic crystallization system, and the residual liquid can be sold as a water reducing agent. Due to the use of both dynamic and static crystallizers, this device not only ensures higher naphthalene recovery rates but also reduces energy consumption.