Hence, increases in H 2 dissolution were observed. Also, by increasing the liquid flow rate, there is more liquid volume for H 2 to dissolve in. Therefore, a more liquid feed is introduced into the reactor, evaporation rates also become faster. According to Raoult’s Law, with the increase of mole fraction of a component in a solution, the partial pressure also increases, and consequently the escaping tendency increases. is the symbol used to represent displacement. refers to the value of the initial position. It can be defined mathematically with the following equation: refers to the value of the final position. An increase in LHSV implies a hike in the feed flow rate (liquid). Displacement is defined to be the change in position of an object. The higher the LHSV the faster will be the vaporization of feed as well as H 2 dissolution. A significantly high LHSV not only reduces the feed & catalyst contact time but also increases the reactor pressure drop and other hydraulic challenges. However, an excessive reduction of LHSV can create the operation difficult due to hydraulic perspective & it can cause channeling which leads to liquid mal-distribution and under-utilization of catalyst.

Reducing LHSV generally results in an enhancement of hydrotreating reaction.

So, LHSV is reciprocal of the space-time.

How does LHSV affect hydrotreating reactions?Īs the Liquid Hourly Space velocity (LHSV) is the ratio of the volumetric flow rate (hourly) of the liquid feed to the volume of the catalyst present in the reactor.