Petroleum Coke is a good Resource for Electrical Energy Generation due to its Price, Availability and its Ability to Produce Hydrogen

Petroleum coke is the residual material from the processing of heavy oils at refinery plants. The petroleum coke is a byproduct of the oil cracking process which converts the heavy oils into further fuels or products. However, in addition, sometimes the heavy oils must be pre-processed by other manufacturing stages known as Flexicoking or Delayed Coking unit operations [ 1. Trommer et al 2005 ]. The use of Petroleum Coke used as fuel in electrical power plants has been steadily increasing since 1995 according to the figure shown above [ 2. EIA 2009 ]. In fact, the use of petroleum based liquids such as distillate oils or diesel has declined markedly during this time period also, maybe due to the fact that alternative carbon based power sources are being used instead. The combustion of petroleum liquids causes more pollution, carbon dioxide emissions and particulates than other means of electrical generation such as Gasification. Although petroleum coke does have some metal content as well as a good amount of sulfur content (~ 5 %), but is still good to use due to its in gasification technology along with calcinization that may help to alleviate the high sulfur content. Coal and other carbon sources have been used in cleaner electrical generation from the use of Circulating Fluidized Bed CFB Boilers. Petroleum coke has also been used in mills such as Pulp and Paper as well as Cement and Brick kilns [Same Internet Reference as Above]. In order for Petroleum Coke to be used effectively in CFB units it must be sold in its Pulverized form, like what is required with coal to operate in CFB's. Even though Petroleum Coke may not be considered a renewable resource by many since it is produced by the Petroleum industry, it is cheap carbon source that should be taken advantage of to produce electrical power.

Like coal, Petroleum Coke may usually be transported by rail not far from the place of its generation. In fact, it appears that only around less than 20 states implement the use of Petroleum coke for power generation according to the EIA. This may mostly be due to the fact that it is not transported far from the places of its generation, which are oil refineries. Petroleum coke also has the advantage in that it can be used to generate hydrogen for electrical fuel cell generation, which is also a cleaner renewable energy based technology. In most of these systems, petroleum coke would also be gasified and then steam reformed into synthesis like gas where hydrogen is then produced. Hydrogen produced from the synthesis gas from petroleum coke has been experimented with solar reactors as well as molten carbonate type of fuel cells [ 3. Trommer 2005 & Cherepy et al 2005 ]. There has also been mention for the use of petroleum coke based power plants in sequestering carbon dioxide by putting it underground near oil wells. This would help to replenish an existing oil well that is partially depleted. Since many oil refineries may be near oil wells, it may make sense to use petroleum coke as an energy source near oil wells and oil refineries. An advantage of petroleum coke is that it is a cheap source of energy and it may be abundant. It is said that petroleum coke is less expensive as an energy source than natural gas. It is uncertain by the author what other products petroleum coke is used as other than electrical energy generation. It is known that coal based coke is used in producing other types of products, somewhat from the tars that are generated. Even though petroleum coke is derived from the petroleum industry, it is a potential energy source that can be used in electrical energy generation, whether it drives turbines or produces hydrogen for fuel cells. The fact that it is cheap and abundant makes it an ideal energy source to help solve our sustainable energy needs.

REFERENCES

1. "Hydrogen Production by Steam-Gasification of Petroleum Coke using Concentrated Solar Power - I. Thermodynamic and Kinetic Analysis", International Journal of Hydrogen Energy Vol 30 No 6 pgs 605-618 [2005] by P.Trommer, F.Noembrin, M.Fasciana, D.Rodriguez, A.Morales, M.Romero, A.Steinfeld

2. "Net Generation by Energy Source", Energy Information Administration (EIA) [2009]

3a. Same as Reference #1

3b. "Direct Conversion of Carbon Fuels in a Molten Carbonate Fuel Cell", Journal of the Electrochemical Society Vol 152 issue 1 pgs A80-A87 [2005] by NJ Cherepy, R. Krueger, AF Jankowski, JF Cooper

KEYWORDS: Petroleum Coke, Sulfur and Metal Content in Petroleum Coke, Hydrogen Generation from Petroleum Coke, Heavy Oil Refinery, Carbon Sequestration in Underground Wells, Solar Generators of Synthesis Gas, Price and Abundance of Petroleum Coke, Circulating Fluidized Beds, Pulverized Petroleum Coke, Pulp and Paper Mills, Cement and Brick Kilns, Products from Petroleum Coke, Electrical Generation from Petroleum Coke

Photos taken from Picasa and graph generated from EIA source 2009 data