Application of ceramic fiber products in ethylene cracking furnace

时间：2015-06-24 Application of ceramic fiber products in ethylene cracking furnace
I. overview:
Cracking furnace is one of the key equipment in ethylene plant, it is the small molecule alkanes or heavy oil atomization and other raw materials in a tube furnace heated to a certain temperature, the reaction equipment of cracking reaction for ethylene 07:48:472010-09-15 (CH2= CH2) propylene CH3CH=CH2 a four carbon C4) products and their by-products.
Two. The technical basis for the application of the refractory fiber products in the ethylene cracking furnace:
Due to cracking furnace temperature higher (1300 DEG C), the centre of the flame temperature high up 1350~1380 DEG C, must have a full understanding of a variety of materials to the material economy reasonable, safe and reliable, can meet the application.
The traditional lightweight refractory brick or refractory brick structure, which is caused by heat conduction coefficient and thermal shock resistance, leads to the super temperature and heat loss of the furnace shell. Refractory fiber as a new type of high efficiency and energy saving material, it has advantages of good insulation properties, high temperature resistance, thermal shock and mechanical shock and convenient construction, is in the world the most ideal refractory heat insulating material. It has the following advantages compared with the traditional refractory materials:
1, with the use of high temperature: with refractory fiber production and application technology development, refractory fiber product has achieved the series and function, product from the use of temperature can meet from 600 C to 1500 DEG C temperature of different grades. From the shape of the most traditional cotton, blankets, blankets, felt products to fiber module, plate, shaped pieces, paper, fiber textile and other forms of two processing or deep processing products. It can meet the needs of different applications in different industries.
2, small volume density:
The volume density of refractory fibre products generally 64~320kg/m3, about 1 / 3 of the light brick, light refractory pouring material of 1 / 5, to design a new furnace body, not only can save steel, can also be further simplifying the structure of the furnace body.
3, heat capacity is small:
The thermal capacity of the refractory fiber products is very small compared with the refractory brick and heat insulating brick. Because their density is different, so the heat capacity difference is very big. The thermal capacity of the refractory fiber products is about 1/14~1/13 of the refractory brick, and the 1/7~1/6 of the heat insulating brick. A cracking furnace for periodic operation can reduce the consumption of non production of fuel.
4, the construction is convenient, the cycle is short
Refractory fiber or a prefabricated into various shapes of block, blanket, blankets, rope, fabric, paper and other, facilitating the adoption of a kind of construction method, due to its excellent elasticity, compression can be predicted, so construction without leaving expansion joints, generally cooked refining industry and trade.
5, after the construction does not require baking and curing
Using of refractory bricks and refractory castable structure to strictly abide by the curve of curing oven and curing period, especially refractory castable health for a long period, usually 4-7 days and reduce the utilization rate of the stove. If the whole fiber lining, such as from other metal components limit, after construction can quickly rise to the process temperature. Not only improves the effective utilization rate of the industrial furnace, so as to reduce the consumption of non production of fuel.
6, the thermal conductivity is very low
Aluminium silicate fiber is a fiber with a diameter of 3-5um, and has a lot of space, and the thermal conductivity is very low. But at different temperatures, the lowest thermal conductivity and its corresponding optimal bulk density, the lowest thermal conductivity and the corresponding volume density, with the increase of temperature. According to the experience of the whole fiber structure of the cracking furnace in recent years, the volume density of the kg/m3 200~220 is the best.
7, have good chemical stability and resistance to air scour:
Refractory fiber only in phosphoric acid, hydrofluoric acid and hot alkali was corroded, is stable to other corrosive media.