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The new alchemy: turning waste into oil and chemicals.

As an energy source in Europe, as an environmental breakthrough in North America, Ensyn Technologies' bio-oil is a winner all around

Canadians are a rather skeptical lot. Breakthroughs in engineering/science are meant for other countries; they couldn't possibly happen here. Oh yes, we know that Bombardier invented the snowmobile, Spar Aerospace's Canadarm on the space shuttle is world famous and that John Polanyi won a Nobel prize, but these and other accomplishments not withstanding, there remains an air of disbelief that Canadians can beat or lead the world in technical fields.

Now, though, there's an ambitious Ottawa-based company challenging this myth and poised to take its place as the world leader in the area of biomass fuels. Ensyn Technologies Inc. has developed the process to produce liquid fuel from waste materials.

Ensyn's Rapid Thermal Processing (RTP) heats biomass to an extremely high temperature (400 to 950 [degrees] C) for just 0.5 seconds at ordinary atmospheric pressure with no oxygen. RTP is also known as fast cracking and is similar to the catalytic cracking process used by the oil industry.

The rapid heating of the biomass causes fragmentation of the structure ("cracks" the chemical bonds) thus producing the liquid bio-oil. The rapid cooling prevents the completion of chemical reactions thus preserving the liquids. Perhaps best of all, the process produces no waste stream. The feedstock can vary: wood waste, cardboard, newsprint, straw, bagasse, lignin, pulp sludge, tires, agricultural residue, rice husks, all kinds of petroleum products.

The idea was born at UWO

The general concept for RTP came from Maurice Bergougnou, FCIC, University of Western Ontario. Ensyn president Robert Graham explained that Bergougnou had worked for 10 years with the oil industry on the development of reactor systems. The aim was to shorten the residence time the raw crude spent in the catalytic cracking unit while simultaneously increasing the process temperature. (The half-second residence time Ensyn has achieved is a fraction of the time used by the oil industry in its catalytic cracking.) This would increase productivity while lowering process costs. At that time -- late 1970s -- Graham noted that the industry was looking at the possibility of a barrel of oil costing $60.

"When we arrived at Western (Graham and Barry Freel, now Ensyn's vice-president, engineering), Bergougnou was convinced that the process could also work with biomass, particularly wood."

The bench unit was built at the University of Western Ontario in 1979-80. The main element in the process is the use of sand as the heat carrier into the reactor system. "That's been the germ idea ever since Western," Graham said.

After graduation, Graham and Freel came to Ottawa and along with Don Huffman founded Ensyn Engineering, now Ensyn Technologies, in 1984. They did a number of scale-ups. These were funded by outside consulting the trio did. "We did not want to sell the technology as a way to raise the capital," Graham explained.

The bench units went from producing a few hundred grams per hour of fuel to 5 kg/h to 10 to 30 all the way up to 200 kg/h. Now, the commercial plant can process 1,000 kg/h. The use of sand was the initial idea; achieving 0.5 second residence time in a commercial plant was the breakthrough.

"It's been an excellent experience going from bench scale units to commercial plants," Graham added. "What's nice is that all the original people have seen it through."

Having the commercial plant (Red Arrow Products Ltd., WI) in the U.S. has been "everything", according to Graham. It's given Ensyn credibility and opened the doors to many other offers worldwide.

Red Arrow produces various food flavorings. Its old process was based on slow pyrolysis of wood. With RTP, the liquid yield is up to 2.5 times as much and the chemical yield is up to 10 times larger. The plant uses 25 to 30 tonnes per day (t/d) of sawdust. This makes 20,000 L/d of fuel.

The chemicals that are stripped out are used for flavorings or can be sold. They include hydroxyacetaldehyde, a substance with many industrial uses, but hard to produce synthetically. The residual liquids are burned to supply process heat to the plant. Red Arrow is number one in the U.S. market for its products with a 55% market share. Graham said that RTP should help Red Arrow increase that share.

The feedstock is not burned

The patented RTP process uses a special reactor and feedstock handling system to convert the wastes into the liquid fuel and saleable chemicals. The technology breaks down the complex chemical bonds of the feedstock into useful fuel and chemical building blocks by subjecting it to a short burst of intense, uniform and precisely controlled heat.

Unlike incineration, RTP does not burn the feedstock. It creates a fast, predictable chemical decomposition process and then arrests the process before the feedstock can degenerate into lower value products such as char or coke.

It must be noted that the RTP bio-oils are not petroleum. The bio-oils are generally not secondary viscous tars such as produced in a traditional slow pyrolysis method. The bio-oils are a mixture of oxygenated chemicals resulting from the degradation of complex biomass structure. The three major components are: water, depolymerized lignin and carbonyls. Other chemical groups include carboxylic acids, carbohydrates, lignin-derived phenolics and alcohols.

The physical and chemical characteristics of the bio-oils are very much dependent on the type of feedstock, process conditions and recovery techniques. Generally, bio-oil has half the heating value of light oil but is still considered to be competitive with petroleum fuel oils on the basis of equivalent energy. The cost to produce bio-oil is about $0.05/L, competitive with No. 6 heating oil.

Graham explained that the more lignin the feedstock contains, the more heat will be generated. Wood wastes usually contain the most lignin. However, the liquid yield will be less. Agricultural products behave like wood. If the feedstock contains mostly cellulosic material, i.e., newsprint, cardboard, the liquid yield will be large, but the heat values will decrease.

The biomass does not need to be pretreated but does have to be dried to a moisture level of 12% and reduced to sawdust size ([is less than or equal to]6 mm). The basic reactor stays the same no matter the feedstock. Although its design is proprietary, the system uses a recirculating transported-bed which achieves rapid heat transfer in a turbulent mixing zone.

The recovery system must adjust to the feedstock. Liquids are recovered differently according to the amount of lignin the feedstock contains. The condensers must be adjusted depending on whether the process is trying to recover fuel or chemicals.

Ensyn can build the smaller plants -- up to 25 t/d -- itself. For larger ones, Ensyn deals with three engineering firms in Canada. The general process equipment is fairly standard, Graham said. "It's a question of designing it for the idea the client has."

Why go to all this trouble? Why not burn the material right away? Graham said that this is the one question people ask most when the process is discussed. There are a number of reasons why.

* Retrofitting fossil fuel-burning equipment to burn wood is next to impossible.

* Transportation: Carrying wood or other low-density waste material any distance at all is very expensive.

* For the short-term, Graham said there is still no way solid wood can be fed into a turbine or diesel engine for power generation. A liquid fuel is needed.

* Legislation: Many governments are now prohibiting incineration of wastes.

* Fifth, and probably most important of all, there is a good market for this type of liquid fuel.

In North America, with the mountains of waste available, particularly wood-based, the driving force for the technology is the environment.

In Europe, with the high cost of energy, Graham said Ensyn's product can "fly" on the energy value alone. However, because there is no waste-water stream and no carbon- or sulphur-based emissions, it also qualifies for biomass tax credits.

In Italy, Ensyn will build a 15-t/d demonstration plant in the Umbria region. Purpose-grown sorghum will be the feedstock. Construction should begin this month. "This is probably the ideal project for us," Graham stated. The European Community has stated the Ensyn process is the one it will back to produce liquid fuel from biomass.

There are some other "hot" projects in the offing. The day ACCN visited Ensyn, Graham was forced to cut short an interview to catch a plane to Alabama to discuss a proposal that had just been made. Alabama, like Ontario and BC, has many piles of wood residue which it cannot landfill.

Ensyn is also talking with British Columbia forest industry-based companies to process the mountains of wood waste which exist there. And, Ensyn believes the old Bioshell plant in Hearst, ON, has possibilities.

For the next few years, Graham sees the bio-oil being used strictly as a fuel oil substitute. This is especially true for areas where there are large quantities of biomass and no alternate disposal means. Even in Europe, where the energy benefits of bio-oil are being touted, high landfill fees make bio-oil an environmental godsend also.

Graham thinks the far east can be a "fabulous" market. "The potential is there to produce purpose-grown biomass to fuel power generators. However, we're not aggressive there yet. We want the technology up and running smoothly here first."

Canada has no sulphur or carbon taxes. Therefore, fuel is relatively cheap. To make it economical, a largescale plant would have to be built. This is one of the reasons Ensyn has gone cross-border in its sales efforts. Estimates show that the bio-oil from a 100-t/d plant could be used to generate 7 to 8 MW of electricity in a direct-fired diesel turbine, enough to meet the needs of 400 to 500 homes for a year.

A reason why industrial customers will probably come first is that the bio-oil has the acidity of lemon juice. It cannot be left standing in a tank unless the tank is made of stainless steel or plastic. Rather than heating residential homes directly, the first large-scale uses of bio-oil will be for electrical generation or industrial heating.

Heat vs propellant

Although its short-term future is as a fuel oil substitute, bio-oil has definite possibilities as a propellant. Graham was off to Finland in June for discussions with Finnish multi-national Wartsila. This company is the world's largest producer of medium-sized diesel engines and is committing $5-7 million to develop an engine which could use bio-oil.

The Finnish equivalent of Canada's National Research Council is also interested in the char byproduct. (If wood is used as a feedstock, 12-13% of it becomes char after processing.) It hopes to produce an activated charcoal and is optimistic about the possibilities.

Ensyn now employs 12 staff and sub-contracts work to the universities of Saskatchewan and Sherbrooke. "We have a headstart over everybody in the world. We're the only ones operating commercially," Graham enthused. "We're making improvements at an accelerated rate. We're up and running continuously, therefore, we can continually develop."

Graham stressed that Ensyn could not have achieved what it has without a lot of support, financial and technical, from various groups. At least $6 million has been spent on research in the last 10 years. Graham acknowledged the role of the BioEnergy Development Program of Canada Centre for Mineral and Energy Technology (CANMET). CANMET is Energy, Mines and Resources Canada's main R&D arm. "They have cost shared dozens of our R&D projects."

Also involved are the Ontario Ministry of Energy's EnerSearch Program and RockCliffe Research and Technology Inc. RockCliff is an Ottawa-based company which helps bring Canadian technology to market. Headed by Dr. Stuart Smith, former chairman of the Science Council of Canada and current chairman of Ensyn's board, RockCliff has invested in Ensyn and provides business management expertise and marketing advice.

There are numerous possibilities for this technology; Ensyn is determined to exploit them all. And it comes from Canada.
COPYRIGHT 1993 Chemical Institute of Canada
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Author:Rodden, Graeme
Publication:Canadian Chemical News
Date:Sep 1, 1993
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