BioCycle Magazine

Marine Resources : Chitin Research Opens Up Crab Shell Profits

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Courtesy of BioCycle Magazine

 Building Human Resources Instead of Landfills

“The product originally designed was a chipboard four-drawer dresser that retailed for $20,” explains McDonald. The material used was chipboard “blows” or imperfect boards that would normally go to the dump. While durable, it was suitable only for garage or storage use. Manufacturing this dresser allowed the woodshop to learn the process and identify markets while perfecting the succeeding products. Examples are the pine/melamine dressers and nightstands that are made from virgin western pine for the drawer face and trim plus imperfect melamine from the cabinet industry. “We are able to access an appropriate product at reduced cost that often is landfilled. The drawer back, bottom and sides are made from postmanufacturing waste hardboard material which we divert from a local manufacturer,” McDonald adds.

“The interesting thing about the wood shop is that we continue to find new ways to add recycled materials into its mix,” he continues. “For example, when one of our housing projects needed expensive triple bead molding, we made it out of recycled water bed frames. Rail materials in another project were made out of a special run of ashwood that would normally be used in our area as firewood. Odd lots of exotic woods from local manufacturers have been remilled to make bases for our glass awards from Aurora Glass. With a little creativity and thought, postmanufacturing waste and recycled materials are now finding their way into all our wood products and housing production.”

A primer painting system for preprimed molding and trim for the construction industry has been set up next to the wood shop that is experimenting with use of recycled paint. If successful, it will solve a problem for the Eugene solid waste department, which is having a difficult time developing a consistent market for its recycled paint program, as well as adding another revenue stream for St. Vincent.


In 1990, St. Vincent did not have enough reusable used mattresses coming into the thrift operation, so staff recommended setting up a mattress factory for rebuilding box springs and mattresses. Since the factory has been operating, thousands of mattresses have been diverted from the landfill. At local transfer sites, trailers have been set up to drop off discarded mattresses. Then the filled trailers are hauled to the SVDP factory, where employees sort the rebuildable and reusable products. New fabric, ticking, foam and cotton are put on the frame, and all rebuilt mattresses are given a one-year warranty. McDonald estimates an 80 percent diversion from the dump of twins, fulls and queen mattresses.

An interesting outgrowth of the mattress factory is a shredding program to deal with mattresses still winding up at landfills. St. Vincent is designing a system to shred all residual products that cannot be either reused or rebuilt. An SVDP affiliate in Oakland, California is implementing a deconstruction system to divert mattresses collected in Alameda and San Francisco counties. For the Bay area, this amounts to more than 300 daily. Processed materials will be directed to these markets: Poly foam and toppers to the carpet pad industry; Steel back to the steel industry; and Wood to hog fuel users. St. Vincent is working with the International Sleep Products Association, the Alameda and San Francisco solid waste departments, and others to demonstrate and expand the process.


Twenty years ago, St. Vincent was rebuilding an average of 25 appliances per month in Eugene. This year, McDonald estimates the number is over 300. White goods that are not rebuildable have their motors removed, oil drained and CFCs recycled. “St. Vincent operations recycle over 16 tons of appliances per day,” he calculates. “Our next venture is likely to be in computer recycling. Our solid waste district is absorbing over 25 tons of computer junk per month. The need is to separate what can be reused, create usable products, and develop new training for our vocational services program. I hope to have this venture in place in Eugene within the year and that our experiences will spur others to develop this kind of sustainable community model where they are located.”

As part of its emphasis on community outreach programs, SVDP has built or restored over 300 units of affordable housing, with 250 more under development this year. Increasingly this focus is incorporating green building activities. Housing encompasses permanent affordable rentals, duplexes, single residence occupancy units, apartments and transitional housing for homeless families.

Explains Amanda Saul of the SVDP staff: “Our program is now taking steps to further its innovative approach to housing development to ensure new buildings have less environmental impact and are healthier to live in.” This means that whenever possible, future housing built by SVDP will use green building materials and techniques such as wheatboard, tankless water heaters, solar heaters and biofiltration swales. “Wheatboard is a particle board alternative that utilizes an agricultural waste product (wheat straw), is superior in performance to particleboard and made with a low toxic formaldehyde-free binder. Tankless water heaters are incredibly energy efficient while grassy swales hold stormwater on site and act to naturally filter water runoff from streets and parking lots before it runs into the river,” Saul continues. “We are looking at all the processes involved in developing housing to find low or no-cost ways to create healthier, more livable housing. Examples include orienting homes to gain maximum solar efficiency, placing developments close to jobs, transportation, and soil services. This strategy will affect all stages of the development process from planning and design, to construction and even deconstruction of buildings. We have compiled a resource book to help members of the development team (from architects to contractors to property managers) identify and locate green products, as well as weigh the costs and benefits of those products.”

Chitin Research Opens Up Crab Shell Profits

Dorchester County accounts for half of the crabs caught annually in the state of Maryland, packing 500 tons of meat in a normal year. Since the early 1990s, Pat Condon and his composting company, New Earth Services, has provided an outlet for the crab chum left after processing (see “Crab Composter Gets Claws On New Feedstocks,” August, 1997). In the past few years, the business has expanded to serve the poultry, clam and food processing industries. Condon’s newest venture, ChitinWorks America, extracts and sells the chitin in crab shells, then sends the residual solids to his composting operation. For the most part, feedstock suppliers in the beleaguered Eastern Shore crabbing industry — who face a labor shortage, price pressures from Asian competition and concerns about Chesapeake Bay pollution — will drop off crab chum at Condon’s chitin factory for free instead of paying a $25/ton tipping fee at the composting site.

The state has provided extensive support for the chitin enterprise in the hopes that Condon will divert more of the millions of pounds of crab chum produced each year on Maryland’s Eastern Shore. “This will provide the crab packing industry with an economical, reliable and responsible method of disposal,” says Condon. “We’re set up to take everything produced in the county.”

Chitin is a naturally occurring plastic component of the crab shell, notes Condon. According to Beyond Waste: Navigating Fishery Byproducts in the Northeast, a publication of Coastal Enterprises, Inc., chitin is the second most abundant organic compound on earth. Its two major sources are the shells of arthropods (e.g. crabs, lobster, shrimp, insects) and bodies of fungi. It is employed most commonly in industrial applications. It can be used for biodegradable sutures or second skins for burn victims, or be woven into bandages that stop bacterial infection and bleeding. Chitin increases the shelf life of meat, fruits and vegetables, and flowers. It is used in the paper and textile industries to produce certain surface properties, and has many other applications. When processed in a chemical treatment to make it soluble in dilute acids, it becomes chitosan, “one of the most versatile chemicals in wastewater treatment.” It can remove organic molecules, heavy metals and PCBs. Chitosan has become more popular recently as a health food product because it reportedly can remove body fats.


Condon became aware of chitin’s value through phone calls from brokers looking for the commodity. He partnered with another company, Venture Chemicals, to conduct research and participated in a project with University of Maryland faculty in 1996 to develop the best production process. Funding included two $70,000 Maryland Industrial Partnership grants and investments from a state fund that targets high-risk, high-yield, high-tech businesses. A few years later, Condon formed ChitinWorks America to pursue commercialization. He assembled a team of engineers and scientists to design the physical plant and equipment that would replicate the chitin extraction process perfected in the laboratory. The National Science Foundation contributed two grants totaling $400,000.

Condon also raised $2 million in capital for the facility, which was built in a Cambridge, Maryland industrial park about 15 miles from the composting facility in Hurlock, Maryland. He established operations in February, 1999, processing 50 to 100 tons of crab shells that year, which essentially served as a shakedown period. In the spring of 2000, more experimentation narrowed the gap between results in the test tube and those in a 6,000-gallon vat. This year, he processed about 400 tons of crab chum in the factory. “In the past two months, we’ve been manufacturing fairly consistent, quality product,” Condon said in November. “We’re only operating at 20 to 25 percent of our daily capacity, which is 20 tons of crab chum — a peak day for Dorchester County crab packers. That only happens from late August through mid-November. We recently started to sell product.”


The process begins when dump trucks offload crab chum onto the factory’s concrete floor. Fresh crab chum smells like steamed crabs, says Condon. Even when there are ten tons at the factory, as long as the material does not sit for a few days, there are no odor problems. A small skid steer loads the material into a hopper. A series of augers delivers shells into a 25-000 gallon holding tank. A dilute solution of caustic soda with a pH of 13.5 dissolves any remaining flesh and prevents further microbial activity or shell degradation. From there, shells are pulled out of the tank with a drag chain. The pieces go up a discharger snout and into a wash process. They are then chopped into quarter-inch particle sizes and conveyed into a mixing vessel, where they is treated with hydrochloric acid to gasify the minerals. The shells go through a sieve screen for solids separation and are washed before entering another caustic solution with a slightly elevated temperature to liquify proteins and produce chitin. After another screening, the chitin is washed and put through boiling lye to remove acetate from the molecule. It is now chitosan. Acid is consumed in the reaction and the caustic solution is recovered. The chitosan is then washed, dried, ground, weighed and packaged for sale.

On a dry weight basis, there is 12 percent yield in the process of extracting chitin from crab chum. Of the remainder, about half is gasified as CO2 and the rest is taken to Hurlock for composting. Due to concerns about soluble salts, it is processed separately from crab chum used for New Earth Services’ premium Chesapeake Blue compost. “It’s in a study pile,” says Condon. “Once it’s finished, we’ll need to test for high conductivity.”

Lime is another byproduct of the chitin process. “It’s not in a form that is saleable,” says Condon. “I don’t know whether we can compost it or process it into a form that can be sold as lime.”

Next season, New Earth Services will take as much crab chum as possible at its chitin factory. Condon expects eventually to pay a nominal fee for it. “It will be an incentive to the industry to keep it clean and fresh, and then maybe we can contract to be sure we have raw material. The tipping fee at the composting site has generated tens of thousands of dollars each year, but the price of chitin is $10,000 a ton.” His research company, Venture Chemicals, has developed a new application for chitin that should increase its market share. Chitin also may become more popular if concern grows about the toxicity of synthetic polymers used for removal of heavy metals in municipal wastewater treatment.

What remains to be seen is how crab chum will get to the chitin factory. Condon would like to see cooperation among the state, crab packers and his operation. “These guys are in the middle of the boondocks, in remote areas driving on country roads, and not everybody has a reliable vehicle to travel the distance every day,” he says. “Funds could be made available for pilot transportation projects, like a transfer station for crab shells. The county brings garbage 40 miles north; there’s no reason why it can’t provide similar service for crab chum.”


Even as the potentially lucrative chitin enterprise takes off, composting remains an important enterprise for Condon. This year, New Earth Services composted about 3,000 tons of clam processing byproducts, 1,000 tons of crab chum, 5,000 tons of feathers and offal, 5,000 tons of poultry processing flotation skimmings, 5,000 tons of poultry litter, and 4,000 to 5,000 tons of food residuals. Roughly equal amounts of wood chip amendment were added to produce 10,000 tons of compost.

Prior to composting, feedstocks are combined in a Jalor vertical mixing wagon. Condon primarily composts in windrows turned by a loader or a 16-foot Scarab turner. A study he conducted with Lewis Carr of the University of Maryland Cooperative Extension compared static pile and windrow composting, as well as different recipes. “They all pretty much ended up making the same type of product in the same amount of time for the same amount of money,” says Condon. He has used feedstock selection and tipping fees to bring the cost of poultry litter composting down from $35 to $5/ton. 
 The easily handled materials are placed in large piles and turned every few weeks. More difficult feedstocks include clam shucking residue, which is the solids portion of clam processing water. “It’s been flocculated with bentonite clay and filter pressed,” says Condon. “It comes to us looking like a big, wet brick. It doesn’t really want to break up, but you need to break it up and expose the surface. Otherwise, at the end of composting, you end up with balls of raw clam protein. We also get 10 tons/day of mustard bran, which is the waste product of a Nabisco Foods plant in Cambridge that makes Grey Poupon for the whole country. It’s very viscous; it mixes with the clams and acts like a lubricant. In addition, feathers and offal are high in nitrogen and tend to clump together. We get the materials that the rendering plant can’t handle. They need to be aggressively turned and agitated to break them open. All of those materials and the crab shells continue to be a challenge.”

Odor control is a matter of proper recipe and pile management, says Condon. A layer of compost is applied to fresh feedstock piles when needed. The situation is helped by the fact that the site is next to a landfill and located in a rural community where many people make a living by raising chickens. “We keep an eye on wind and weather when scheduling turnings,” adds Condon. A series of created wetlands has been installed to control erosion and stormwater runoff. Planting of marsh grasses is continuing.

In the past, New Earth Services shipped its product to West Virginia to have it bagged. The Environmental Protection Agency awarded a $150,000 grant to install a regional bagging facility at the composting site. The plant is operated by New Earth Services, but the grant itself went to the Warrington Foundation, a nonprofit organization run by Herb Brodie, a retired University of Maryland professor, to assist the farming community with nutrient management issues. A $300,000 grant from the Maryland Animal Waste Technology Fund also funded the project. Construction has just been completed on the 7,000-square-foot building, which has an Inglett bagging line capable of filling one million bags/year. It is available for any other poultry litter composters on the DelMarVa Peninsula who are willing, like New Earth, to pay an access fee for every bag filled. “It may be that the future of our company is helping people make good compost by assisting with techniques, and helping sell material in the market,” says Condon. “We see our forte as getting product to market, whether we do it as a broker or for ourselves. I don’t see any reason to dissuade other people from composting — there are 800,000 tons of poultry litter to manage in the region.”

More government assistance is available through a transportation subsidy for movement of poultry litter from inundated farmland areas to farms that need it. Delaware and Maryland have initiated programs, and Delaware has approved alternative use facilities such as composting sites as destinations for the litter. Maryland’s decision on this addition to the program is pending. “We’ve just started to receive manure from Delaware,” says Condon. “If I were left to my own resources, I would have to charge a tipping fee for taking poultry litter. Before, we took minimal amounts. With the transportation subsidy and the ability to get a better value through bagging, there is an economic reason to get into it more.”

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