Reduced Crude Conversion
Publication Date: 2012-Sep-15
The IP.com Prior Art Database
Page 01 of 16
REDUCED CRUDE CONVERSION *
~URPHY, E.L. WHITTINGTON AND C.P. CHANG PULLHAN KELLOGG - HOUSTON, TEXAS
Throughout the history of petroleum refining, the industry has faced challenges. Today is no exception. Today's challenges fall into three main areas.
One is a change in the pattern of product demand. In many parts of the world, there is a shift in demand from heavy fuel to lighter products. Table 1 illustrates this. Except in the United States, the growth in demand for fuel oil is well below the growth in demand for lighter products.
A second challenge is the growing concern for protection of the environ- ment. This affects the refiner in two ways. He must control pollution within the refinery and at the same time produce products which are more environmentally acceptable. Within the refinery he must concern himself with control of emissions of particulates, sulfur oxides, carbon monoxide~ control of water pollution and even solid waste disposal associated with spent catalysts. Environmental concern is affecting products in the removal of lead from-gasoline andthe lowering of permissible sulfur
levels in fuels. ,
A third challenge facing refiners is the higher cost of crude oil and energy. This prompts him to shift his product slate to maximize the most valuable products and to do this using a minimum amount of energy- consuming utilities.
Trends in Product Demand Toward Light Products
The impact of the~e several factors is pa#ticularly great on the prgc~ssing of residual oils. Historically, most crude residues have been used for heavy fuel production. We can see the recent pattern in Table 2. This shows the trend of refinery yields of fuel oil in various parts of the world outside of the Communist area. In 1974, about 28 percent of crude processed was yielded as residual fuel. Notice this varies greatly from one part of the world to another, from a high of 48 percent in South America to a low.of only seven percent in the United States. In 1975, South American yield decreased to about 43 percent while U.S. yield increased to eight percent. Other areas fall in between, but are mainly on the higher side. The low yield of residual fuel in the United States partly reflects the lighter crudes which have been run, but mainly, it results from the processing schemes used in the refineries. This suggests that on a worldwide basis a large shift in yields can be made using
* Presented by A. K. Logwinuk
Page 02 of 16
The various needs for processing the bottom of the barrel fall basic categories: desulfurization to produce low sulfur fuel conversion to produce lighter products.
into two oils and
Much has been published on the subject of desulfurization. It is well known that the contained metals and the coke forming tendency of residues greatly complicate desulfurization. Crudes with relatively low metals and asphaltenes can be desulfurized directly. Crudes with higher metals and asphaltenes require indirect desulfuriz...