The Arkenol Technology Center (located in Orange, CA) is contained within a 15,000 sq. ft. warehouse building in an urban area zoned for light industrial use. The Center contains the Arkenol Pilot Facility and support facilities and is operated by Applied Power Concepts. The Analytical and Fermentation Laboratories are also operated by Applied Power Concepts.The Arkenol Pilot Facility is rated at a nominal 1 ton per day biomass throughput, assuming a 24 hour, 3 shift operating schedule. During normal operation, 1 shift per day is sufficient for feedstock studies, design trials, and normal maintenance. The Facility was constructed using readily available pilot equipment using no exotic materials.An integrated, full-scale commercial process plant consists of five basic unit operations:
The production of chemicals by fermenting various sugars is a well-accepted science. Its use ranges from producing beverage alcohol and fuel-ethanol to making citric acid and xantham gum for food uses.
Arkenol Inc. has developed significant proprietary improvement to a well known conversion technology known as concentrated acid hydrolysis such that the process is ready for commercial implementation. The Technology is unique in that, for the first time, it enables widely available cellulosic materials, or more commonly, biomass, to be converted into sugar in an economically viable manner, thereby providing an inexpensive raw material for fermentation or chemical conversion into any of a hundred different specialty and/or commodity chemicals. We call this our biorefinery concept.
Biomass feedstocks include:
The ability to utilize low cost feedstocks, and/or those that command tipping fees, to produce products that sell into highly efficient markets provides a viable business that can be sited in almost any geographic area, urban or rural. Due to its moderate use of thermal energy, the production of no waste streams, its significant environmental benefits, and minimal permitting requirements, the Technology also makes an ideal “thermal host” for cogeneration facilities.
Development History - It has been known for over 100 years that acids act as catalyst to convert (“hydrolyze”) cellulose and hemicellulose into simple sugars (hexose and pentose, or “C6 and C5″ sugars). The Germans and Russians used this simple procedure in the early part of this century to produce alcohol fuels and chemicals from wood in order to supply their war efforts. During this same period, a similar plant was operated in the United States in Oregon. However they all shared a similar characteristic – they were not economically competitive with low cost petroleum products because of poor yields, high wastage, and the large volume of unmarketable by-products. Except for a few plants in Russia, the technology fell out of use after World War II.
However, interest in the conversion of biomass-to-sugars picked up in the mid 1970’s due to the oil embargo and the United States’ desire to lessen its dependence on foreign chemical and fuel feedstocks. Further interest was stirred in 1983 when DuPont published an article in Science magazine detailing the variety of chemical products that could be produced via fermentation of sugar. Since that time many universities and government laboratories have been studying the hydrolysis of cellulose, either through the application of various acids or enzymes. Most notable in regard to acid hydrolysis, had been the work undertaken at the Tennessee Valley Authority and Mississippi State University.
In 1989 Arkenol, as a related company to ARK Energy, began researching several technologies in order to develop thermal hosts for siting in conjunction with ARK Energy power plant projects that were being bid into local utilities. Arkenol determined that the concentrated acid hydrolysis process could be made economically viable through the use of new technology, modern control methods, and newer materials of construction. Arkenol engineers and their consultants were able to solve the problems with the following proprietary improvements that now make the process economically viable:
Process - To demonstrate the efficacy of the Technology, Arkenol has constructed a pilot plant near its Southern California offices. An integrated, full-scale commercial process plant consists of five basic unit operations:
Simply put, the process separates the biomass into two main constituents: cellulose and hemicellulose (the main building blocks of plant life) and lignin (the “glue” that holds the building blocks together), converts the cellulose and hemicellulose to sugars, ferments them and purifies the fermentation liquids into products. These unit operations require a series of material and energy inputs to produce the primary products of fermentation and the resultant by-products.
If there is no power plant present from which to obtain steam, the production facility would use natural gas or lignin as fuel for its own boilers.
Incoming biomass feedstocks are cleaned and ground to reduce the particle size for the process equipment. The pretreated material is then dried to a moisture content consistent with the acid concentration requirements for decrystallization (separation of the cellulose and hemicellulose from the lignin), then hydrolyzed (degrading the chemical bonds of the cellulose) to produce hexose and pentose sugars at the high concentrations necessary for commercial fermentation. Insoluble materials, principally the lignin portion of the biomass input, are separated from the hydrolyzate by filtering and pressing and further processed into fuel or other beneficial uses.
The remaining acid-sugar solution is separated into its acid and sugar components by means of an Arkenol-developed technology that uses commercially available ion exchange resins to separate the components without diluting the sugar. The separated sulfuric acid is recirculated and reconcentrated to the level required by the decrystallization and hydrolysis steps. The small quantity of acid left in the sugar solution is neutralized with lime to make hydrated gypsum, CaSO4 · 2H2O, an insoluble precipitate which is readily separated from the sugar solution and which also has beneficial use as an agricultural soil conditioner. At this point the process has produced a clean stream of mixed sugars (both C6 and C5) for fermentation into a wide assortment of fuels and chemicals.