August 15, 2004 | General


BioCycle August 2004, Vol. 45, No. 8, p. 46
With facilities in Montana, Idaho and Hawaii, a company takes stock of its accomplishments, challenges and opportunities – while getting ready to accept an award for excellence.

LAST MONTH, the staff who operate the EKO Systems composting site on Maui, Hawaii learned that they received the Gold 2004 Composting Excellence Award from Solid Waste Association of North America (SWANA) for their “commitment to achieving the highest standards in the solid waste industry.” According to John Harder, chief of Maui County’s Solid Waste Division, nearly 50 percent of the county’s landfill diversion is the direct result of EKO and its sister company, Pacific Biodiesel (see sidebar).
Opened in 1995, the 10-acre site processes biosolids, yard trimmings, woody residuals, paper waste and grease trap cleanings. “The cocomposting program has become the cornerstone of our diversion program, accounting for over 40,000 tons of material a year,” points out Harder.
Maui County’s efforts to develop a cocomposting project were initiated in the early 1990s with the anticipation of the implementation of Subtitle D of RCRA. EPA’s regulations banning commercial liquid residuals from being landfilled would take effect in October, 1993. At that time, all of the County’s sewage sludge – nearly 30 tons/day – was disposed at the Central Maui Landfill. To comply with new state and the federal Subtitle D requirements, the county initiated a pilot project using a small Morbark chipper and windrow composting to manage the sludge. “The project encountered numerous problems, such as unacceptable odors, flies, and cross contamination of finished product,” recalls Harder. “We learned a great deal about the process, especially about what not to do. However, being certain we never wanted to return to landfilling sludge, the county issued a Request for Proposals in 1995 for a contractor to manage all of its sewage sludge and fats, oils, and greases (FOG) and awarded an operating contract to Maui EKO Systems.”
EKO quickly upgraded the existing site, converting the windrow operation to an aerated static pile system, purchasing a Duratech HD 10 Tub Grinder, and aggressively monitoring and maintaining the required temperatures. Within a few months odors decreased, vector problems were eliminated, and the issues with recontamination were corrected. EKO initiated an aggressive public education and marketing plan that resulted in a high level of public acceptance of a project that had almost been shut down due to odors and poor management.
“Our biggest challenge, ” says EKO vice president Mike Hegedus, “is that we’re operating in a landfill and handling five major waste streams. The good news is that we’re recycling 100 percent of all these feedstocks. We grind all wood and green waste coming into the landfill, even though it’s more than what we need for combining with the biosolids. Excess ground green waste is used as mulch on closed county landfills and other sites.”
Adds Harder: “The operation was quickly integrated into the County’s overall Solid Waste Management strategy and EKO became more of a partner in our waste diversion efforts than a contractor.”
Yard trimmings, wood and paper residuals (everything from leaves and limbs to palm fronds and cardboard) are received at a site adjacent to the landfill and ground into 5-inch minus size. The resulting mulch is placed on the sludge receiving bay floor along with oversized woody material from the compost screening process.
Cooking oil is delivered and processed into biodiesel through a process known as transesterification, with the extracted glycerol and oil wash waters placed on the sludge bay floor. The ester is then processed to yield the biodiesel. Grease trap waste is processed into bunker (boiler) fuel, with the extracted grit and minor amount of food scraps placed on the sludge bay floor.
Biosolids are placed on the sludge bay floor and combined, using a Harsh mixing truck, with the mulch, glycerol extract, wash waters, grit and food scraps. Materials then are put into aerated static piles for 60 days to complete the first composting phase, followed by another 60 days of initial curing on a separate pad. Next, material is screened through a Powerscreen trommel, with the overs reused in the initial mix. Samples from the screened material are analyzed at an independent lab for Part 503 requirements, and if that batch receives a passing analysis, it is screened a second time and cured for about 45 days, after which is it put into windrows on another pad to bring temperatures down. A Scarab turner is used for aeration during this final curing phase, which takes another 60 days – bringing total processing time to about nine months.
EKO Systems has found that the low-tech aerated static pile method planned for the site is more adaptable in accepting various feedstocks than some of the more modern high- tech systems that are restricted to specific feedstocks. For example, the types of vegetation on Maui are different from those found in many areas of the mainland. Composting techniques were modified to deal with the high percentage of fibrous palm fronds, plant trimmings with high water content, and hard koa woods.
EKO’s contract with Maui County only requires that it accepts and processes the quantities of green waste necessary to provide adequate bulking agent for the cocomposting operation. However, as the County’s program to maximize green waste diversion has grown, EKO has taken on the task of managing all the green waste entering the landfill. Currently, they receive about 50 tons/day from commercial haulers, businesses, and residences, processing it in a Morbark 1300 tub grinder. EKO doesn’t charge the county a tipping or grinding fee for this service. The County is buying some of the excess mulch for erosion control at the new landfill entry and at two closed landfills. The availability of this mulch has resulted in improved operations and reduced costs to the county.
Five different products are made with the EKO compost: 3/8th inch compost (30 percent of sales); 3/16th inch (20 percent of sales); 3/8th inch plus topsoil (30 percent); 3/8th inch or 3/16th inch with sand (15 percent); and the newest, Greenscape Blend that includes sand and gypsum. The compost facility participates in the U.S. Composting Council’s Seal of Testing Assurance program.
In its bagging plant, the company uses a Bouldin & Lawson 1.5 cu. ft. and 1 cy bagger, packaging 12 percent of its volume for sale to nurseries and hardware stores. The rest – 88 percent is sold in bulk to golf courses, resorts, condominiums and highway departments. Golf courses include the Plantation Course at Kapalua, home of the PGA Mercedes Championship; Kanapali North, home of the Senior PGA; and the courses at Makena in Wailea. The Grand Wailea and Hyatt Regency in Lahaina are some of the resorts using the compost.
Product pricing is as follows: Bags — $4-$4.25 wholesale, $7-$9 retail; Bulk (cy) — $25-$33 wholesale, $36-$47 retail; Blends — $30-$52 wholesale, $35-$65 retail.
In addition to the Maui facility, EKO Systems, Inc. operates two other sites – in Missoula, Montana and Lewiston, Idaho. Though all three use aerated static piles, different feedstocks, tract sizes, regulations and markets lead to operational contrasts. (That’s why Maui is only one-third of the story.)
The Missoula location was launched in 1977, cocomposting biosolids with wood residuals from lumber mills, log home producers and Christmas trees. Annual capacity is estimated at 33,000 cubic yards; the 34-acre site includes a large bagging plant and warehouse, sales and administration office, plus a large maintenance shop.
Product sales in Missoula break down this way: 3/8th inch compost (64 percent); 3/8th inch minus lawn topdressing (8 percent); 3/8th inch compost plus pumice “clay buster” (6 percent); 3/8th inch compost plus sphagnum peat plus pumice (6 percent); 3/8th inch planting mix with compost, peat and pumice (6 percent); and 3/8th inch potting mix of compost, peat and perlite (10 percent).
Bagged material – 40 percent – is marketed to Home Depot and nurseries. The balance of 60 percent moves in bulk to mine reclamation, landscapers, nurseries, athletic parks, municipal parks and several golf courses. Product pricing is as follows: Bags – $2.99-$3.59 wholesale, $3.99-4.99 retail; Bulk (cy) – $16.35-$34.65 wholesale, $25-$46.75 retail.
When it comes to the biggest opportunity for EKO’s Montana site, Mike Hegedus sums it up this way: “Because of our 27 year branded image, Home Depot approached us in 2001 as they opened stores in the Northern Rockies. This actually led to a major hurdle for us, as all prior consumer sales were through independent nurseries that have an aversion to ‘big box’ retailers. But, as things turned out, the independents experienced only a minor dip in sales since we were selling to all at the same wholesale price and Home Depot was selling at suggested retail. Our biggest challenge comes from a logging company that started composting to move wood waste that was costing money to landfill. Though product quality is not comparable, the company sells it for a few dollars over what it costs it to make the product, putting extreme pressure on bulk prices, especially in mining reclamation and revegetation projects.”
The EKO Lewiston, Idaho program began in 1991 to compost biosolids with green waste from six cities as well as homeowners. Annual capacity on the tight, eight-acre site is 25,000 cy. That includes a small bagging plant, shop, outdoor warehousing, plus small sales and administration office.
Product sales are similar to the Montana operation: 3/8th inch minus compost (77 percent); 3/16th inch minus lawn topdressing (5 percent); 3/8th inch compost plus pumice (3 percent); 3/8th inch compost/peat/ pumice planting mix (7 percent); 3/8th inch compost/peat/perlite potting mix (8 percent). Thirty percent of bagged product (1.5 cu.ft. bags) is sold to Home Depot and nurseries; 70 percent bulk goes to landscapers, nurseries, parks and some golf courses. Product pricing is the same as in Missoula.
In evaluating the Idaho site’s biggest opportunity, Hegedus sees major market potential in Spokane and Tri-Cities Washington along with Boise “though freight to the latter is expensive and there are quite a few dairy manure composters in that Boise-region. We have significant opportunity with mining reclamation work in Silver Valley, Idaho if specs between government and contractors can be enforced.” The biggest challenge in his opinion comes from odor complaints from a vocal minority “of two” who blame EKO for all odors, even though immediate neighbors to the site include a large paper mill, a brine water pea processing plant, and two wastewater treatment facilities. Explains Hegedus: “While the high amount of green waste, especially grass clippings during spring, can cause a temporary problem, only one citation was given in 14 years, and it was immediately solved by getting rid of the premix pile and adding biofilters. But some people will always smell with their eyes and once their minds are made up, they’re made up.” – J.G.
Much information used in this article was excerpted from the County of Maui’s nomination package prepared for the SWANA 2004 Composting Excellence Award. The nomination package was prepared by John Harder, Chief of the Solid Waste Division in the Maui County Department of Public Works and Environmental Management and Hana Steel, Recycling Coordinator, both of whom have been champions of composting and organics recycling in Hawaii.
THE SWANA 2004 Composting Excellence Award – to be presented at the organization’s 42nd Annual Expo in Phoenix in September – will be given to both EKO Systems and Pacific Biodiesel. Founded by Robert King in 1996 and now a sister company to EKO Compost, Pacific Biodiesel grew out of local concerns over discarded grease that was clogging the central Maui Landfill, leading KIng to develop his alternative energy approach. His Maui plant annually produces up to 200,000 gallons of premium fuel, while recycling over 36,000 tons/year of used cooking oil from the landfill.
As described in the nomination application prepared by the Solid Waste Division of Maui for the SWANA award, the initial contract with EKO required that they receive and process the fats, oil and grease (FOG) as part of the composting operation. While cooking oil waste is more easily handled in composting than grease trap waste, serendipity was about to happen. King Diesel, a local diesel generator supplier, identified a new process to convert cooking oil into an environmentally friendly biodiesel. Approaching the County and EKO, it proposed a joint venture at the composting facility. In fact, not only would it produce a sellable biofuel, the residuals (water, potassium hydroxide, and triglycerides) that had no identifiable after-market, would be useful feedstocks for the composting process.
On the other hand, the grease trap waste was an operating problem (versus the opportunity with the cooking oil) for both Maui County and EKO. At the time, the major issue for the county was the management of the residue from the sewer lift stations. In 1999, after a number of costly sewage spills, the county’s Wastewater Division began the implementation of an aggressive grease interceptor ordinance, requiring restaurants and other food service businesses to significantly increase their grease trap capacity and keep the problem material out of the sewer lines.
The volumes of grease trap waste grew nearly exponentially, putting a strain on the composting process. It was creating “hot spots” within the piles, leading to spontaneous combustion fires that were not appreciated by the local fire department, especially since they tended to occur at night. Further, it compounded odor and vector problems. Also, it was arriving in sporadic amounts, imbalancing the necessary blending ratios.
The county, EKO, and Pacific Biodiesel asked themselves if they could convert the cooking oil, why not the grease, albeit into a lower grade boiler fuel. The separation of the grease trap waste was much more problematic than the cooking oil residual, but again, the synergy of the two operations resulted in an innovative and cost-effective solution for the county. Today, over 120,000 gallons of biodiesel and 75,000 gallons of boiler fuel are being produced and consumed yearly. A number of large users are realizing the benefits of the new biofuels, including Maui Electric Company. Maui Recycling Service, a private curbside collection service, uses biodiesel in all its vehicles. Maui Bio-Beatle converted the new Volkswagen Bug to diesel and started the only biodiesel car rental company in the country. Hawaii Cane and Sugar and RimRock Asphalt are converting their boilers to biofuel. During the past few years, the county has been using biodiesel in a number of its vehicles and will be converting its diesel tanks at all county baseyards to biodiesel next year.
The high-tech biofuels side of the system uses a series of varying sized tanks for receiving, heating, washing, reacting, storing, and dispensing of the liquids. A combined office, laboratory, and control room runs the entire operation, which all sits atop a curbed concrete pad to catch any spills. The system is self-contained and, thus, not only effective, but highly efficient.

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