1.由石油烃制得：催化重质重整油，催化裂化轻循环油，裂解制乙烯的副产焦油等；

1. Produced from petroleum hydrocarbons: catalytic heavy reforming oil, catalytic cracking light cycle oil, by-product tar from cracking to ethylene, etc;

2.由煤焦油分离，高温煤焦油中萘约占8%-12%，将煤焦油蒸馏，切取煤油，经脱酚，脱喹啉，蒸馏得成品萘。每吨萘消耗10t煤焦油；

2. By separating coal tar, naphthalene accounts for about 8% -12% in high-temperature coal tar. Distill the coal tar, cut the kerosene, remove phenols, remove quinolines, and distill to obtain finished naphthalene. Each ton of naphthalene consumes 10 tons of coal tar;

3.粗萘经白土精制而得精萘；

3. Refined naphthalene is obtained by refining crude naphthalene with clay;

4.降膜分步结晶法 结晶法生产过程由产品生产工艺系统、能源系统、氮气密封系统和计算机控制系统等组成。生产工艺系统以大循环为生产周期，每个大循环包含4个小循环，每个小循环又包含4～6个段，每个段由结晶、部分熔融和全部熔融3个步骤组成；

The production process of the falling film step-by-step crystallization method consists of a product production process system, an energy system, a nitrogen sealing system, and a computer control system. The production process system takes a large cycle as the production cycle, with each large cycle containing 4 small cycles and each small cycle containing 4-6 segments. Each segment consists of three steps: crystallization, partial melting, and complete melting;

（降膜结晶法操作工艺实例：由工业萘装置送来的液态工业萘送入馏分槽中，当进行第四段结晶操作时，用泵将槽中的原料液送入动态结晶器收集槽中。未结晶萘油与发汗液放入纯度低一级的馏分槽中，全熔液可作为第五段的原料。按预定程序进行六段结晶精制后即可得到产品精萘。为提高萘的提取率，可将富含硫茚的馏分送往静态结晶器中处理，静态结晶器所得的产品返回动态结晶系统的相应馏分槽，残液可作为减水剂出售。由于该装置同时采用动态和静态结晶器，既可保证较高的萘回收率，又能降低能耗。）

Example of falling film crystallization operation process: 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 pumped into the dynamic crystallizer collection tank. Uncrystallized naphthalene oil and sweating liquid are placed in the lower purity distillation tank, and the full melt can be used as the raw material for the fifth stage. After six stages of crystallization refining according to the predetermined procedure, the product refined naphthalene can be obtained. To improve the extraction rate of naphthalene The fraction rich in sulfur indene can be sent to a static crystallizer for processing, and the product obtained from the static crystallizer can be returned to the corresponding distillation tank of the dynamic crystallization system. The residual liquid can be sold as a water reducing agent. Due to the use of both dynamic and static crystallizers in this device, it can ensure a high naphthalene recovery rate while reducing energy consumption

5.静态分步结晶法 将原料工业萘装入结晶箱后进行快速降温，降至82℃后转为均匀降温，以2℃/h的降温速度冷却至60℃，排放富含硫茚的第一次晶析萘油，作为中间馏分待后处理。然后结晶箱内的物料以4℃/h的速度升温，间隔0.5h取样一次，测定其结晶点，根据结晶点的不同，分别排入对应馏分槽，如此进行3～4次分步结晶，可得到较高纯度的精萘。

5. Static stepwise crystallization method: The raw material industrial naphthalene is loaded into a crystallization box for rapid cooling, and after cooling to 82 ℃, it becomes uniformly cooled. It is cooled at a cooling rate of 2 ℃/h to 60 ℃, and the first crystallization naphthalene oil rich in sulfur indene is discharged as an intermediate fraction for post-treatment. Then, the material inside the crystallization box is heated at a rate of 4 ℃/h, and samples are taken every 0.5 hours to determine its crystallization point. According to the different crystallization points, they are discharged into the corresponding distillation tanks. This process is carried out 3-4 times in steps to obtain high-purity refined naphthalene.

更多的关于精萘厂家问题或者详细的内容，请进入我们公司的网站：http://www.jnjdbc.cn网站中会有很多的内容仅供参考

For more questions or detailed information about refined naphthalene manufacturers, please visit our company's website: http://www.jnjdbc.cn There will be a lot of content on the website for reference only