Industrial application of combined process of continuous reforming isomerization

The 0.3Mt/a low-temperature C5/C6 isomerization device was delivered in mid-March 2014, the preparation began in April. After the completion of the device's purging, air-tight and instrument debugging, various additives were filled in May, the trial operation of the isomerization device was started. In early July, the acidizing and drying treatment of the hydrogen hydroforming system was carried out, and the water mass fraction of the hydrogen hydroforming system was controlled below 1μg/g. 

From July 14 to 18, the isomerization catalyst was loaded with a total loading capacity of 36.2t. At the same time, the operation of other units of isomerization was adjusted to meet the oil intake conditions of the reactor, the adjustment operation of the reforming pre-fractionation tower was carried out to ensure that the properties of the top pull oil met the feeding requirements of the C5/C6 isomerization device, and the properties of the bottom reforming feed met the feeding requirements of the reforming device. On July 20, the isomerization device was injected with oil, the device began to operate smoothly soon after the oil was injected. On August 5-7, the initial calibration of the isomerization device was carried out.

Compared with the design value, the calibration range of the actual raw material is 30.5~79.6℃, the content of C4 component is slightly increased, the mass fraction is 5.19%, and the content of recombination C7+ is also increased, reaching 4.59%. The inlet temperature of the prereactor is 135.7℃, the outlet temperature is 169.8℃, and the temperature rise is 34.1℃. The inlet temperature of the post-reactor was 121.7℃, the outlet temperature was 124.7℃, the temperature rose to 3℃. It could be concluded that the isomerization catalyst had good isomerization activity from the temperature changes. 

The yield of the isomerized product was 87.71%, the RON and MON of the isomerized product reached 85.2 and 84.9, respectively, which increased by 18.0 and 19.8 units compared with the feedstock. The saturated vapor pressure of the product was 87.5kPa, each index reached the design control index. As of July 2017, the unit has been running smoothly for more than 3 years, producing high-quality clean gasoline blending component -- isomerized gasoline with RON no less than 85.