Hydrogenated diesel color issue?
Thread Content
My unit is used for the mixed hydrogenation of coker diesel and gasoline; the reactor pressure is 3.5–4.0 MPa. It has just started operating recently. The color of the diesel sample is acceptable, but its chromaticity is 2.0. The color turns red after being left for some time. What could be the reason for this?
The hydrogenation depth is probably not sufficient. If it turns red upon placement, it indicates poor oxidation stability, meaning that the impurities in the coker diesel and gasoline have not been completely removed. The reaction pressure of coker gasoline and diesel at 3.5–4 Mpa is a bit low; it would be better to increase the amount of recycled hydrogen as much as possible in order to raise the hydrogen-to-oil ratio.
We keep the device pressure at 4.8 MPa; devices with higher pressures exist as well. If the pressure is too low, it can also have an impact on the desulfurization efficiency···
Reply to 1#: Haike, the quality of coker diesel is already poor. With such low reaction pressure, it definitely won’t work; a low pressure means a low hydrogen-to-oil ratio, and as a result the denitration effect will be poor. Raising the pressure to 6.5 Mpa should solve the problem.
Reply to 2# net2002163: Your pressure control is too low, and the hydrogen-to-oil ratio is relatively low as well. The pressure or the amount of circulating hydrogen should be increased
Have the organic compounds (aromatics) been oxidized?