CA2360981A1

CA2360981A1 - Process for producing high-octane fuels from renewable resources

Info

Publication number: CA2360981A1
Application number: CA002360981A
Authority: CA
Inventors: Ronald B. Fletcher
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-11-02
Filing date: 2001-11-02
Publication date: 2003-05-02

Abstract

A process for efficiently manufacturing a synthetic fuel from a renewable resource whereby grains and fruits are first converted to alcohol and the alcohol is then partially converted to a high-octane, high-quality hydrocarbon fuel. The processed grains and fruits can be reused for other purposes.

Description

TEM File no. 240.1 TITLE: Process for Producing High-octane Fuels from Renewable Resources FIELD OF THE INVENTION
The present invention relates to producing high-octane fuels in general, and in particular to producing such fuels in a cost and energy efficient manner using renewable resources.
BACKGROUND
Gasoline usage worldwide is increasing while natural reserves are decreasing and therefore it appears essential that gasoline or alternatives fuels must be manufactured from renewable resources in the coming future.
One such fuel, which can be made from a renewable resource, is Ethanol.
Specifically, organic vegetation, such as wheat, barley, corn, etc., containing carbohydrates may be converted to sugar, which may then be converted to alcohol when allowed to ferment. The overall process is somewhat energy intensive, as the final product (namely alcohol) must be separated from water utilizing a distillation process. The efficiencies of conversion plants vary as some require an energy input of up to 50,000 b.t.u.'s to produce one (1 ) gallon of alcohol having an energy value of 85,000 b.t.u.'s.

The small net gain in energy becomes a limiting factor with respect to the economical feasibility of using a renewable resource for fuel. Further, although alcohol can be utilized as fuel in internal combustion engines, its inherent energy value of 85,000 b.t.u.'s per gallon is low compared to gasoline with a value of approximately 110,000 b.t.u.'s per gallon.
In view of the aforementioned problems, it is an object of the present invention to provide a process for efficiently and economically producing a high-octane fuel from a renewable resource with an energy value comparative to gasoline.
DESCRIPTION OF PROCESS
Drawing #1 illustrates a typical prior art ethanol production process where grains (such as barley, wheat, corn, etc.) and water are introduced into tank 1.
The grains and water are initially mixed and cooked in tank 1 at a temperature of 190 degrees F for approximately 12 hours. The resulting grain/water mixture is then cooled to 140 degrees F and allowed to remain at this temperature for 12 hours. Yeast is then added and the mixture is cooled to 90 degrees F, and allowed to ferment for approximately 60 hours. The mixture, or "mash", is then pumped to a separation tank 2 where the solids exit from the bottom of the tank and the remaining liquid, which is approximately 12% alcohol at this point, is pumped to the distillation tower 3. Water exits from the bottom of the distillation

2 tower and 190 proof alcohol exits from the top and is passed by a series of cooling fins 4 to reduce the alcohol's temperature. Depending on design and other conditions, the energy requirement to produce a gallon of alcohol ranges generally between 19,000 to 50,000 b.t.u.'s.
Drawing #2 illustrates a process for producing synthetic fuel according to a preferred embodiment of the present invention. The prior art ethanol production process is modified in two manners. First, a heat exchanger 8 and a hot water storage tank 7 are added to the production process as shown to re-use the heat generated in the ethanol production process. In doing so, the theoretical energy input requirements are reduced to an estimated 6000 b.t.u.'s as compared to the earlier noted requirement of about 19,000 to 50,000 b.t.u.'s, namely an anticipated decrease in energy input of approximately 68%.
Second, a catalytic converter 5 is provided downstream of the cooling fins 4 for de-oxygenating the alcohol to produce a useable hydrocarbon fuel in the - Coo range, and in so doing the fuel becomes immiscible with any remaining water and may be separated in the separator 6.
In the catalytic reaction, conversion from alcohol to a hydrocarbon is a function of pressure, temperature and space velocity, and normally would be operated to achieve 100% conversion. In contrast, it is an object of the process of the present invention to provide operating conditions, with respect to temperature, pressure, and space velocity, wherein only 85% conversion is

3 accomplished. In doing so, a more commercially valuable, higher-octane fuel is produced.
Accordingly, additives, whether lead or non-lead, should not be required downstream to enhance octane ratings prior to sale or use of the fuel.
In addition to the benefits of producing a high-octane fuel by the present process, the catalytic conversion is an exothermic process whereby heat is generated. Hence, by including an additional heat exchanger in the present process, the aforementioned heat may be cycled back to the primary alcohol section of the process to further reduce energy requirements.

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