By SHARON UDASIN
04/13/2011 03:04
Next step is to use organic wastes to create fuel for coal-fired power plants.
In an effort to combat the annual dumping of 250,000 tons of sludge into the Mediterranean Sea from the Dan Region Wastewater Treatment Plant, a network of companies have come together to launch a technology that transforms it into useable, fertilizing soil.
The project, called DAN-VIRO, has been a decade in the making and employs the patented system and machinery designed by American company N-VIRO, which for 21 years has been transforming American sludge into viable soil and is excited to have Israel as its first foreign customer other than Canada.
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Over the past couple of weeks, the DAN-VIRO system officially started running its pilot program based at its facility within the treatment plant (the Shafdan) and it has already begun distributing soil to southern kibbutzim.
DAN-VIRO is 61 percent owned by Global Environmental Solutions, a branch of Granite Carmel in the Azrieli Group, with the remaining shares held by Shtang Construction & Engineering, CRM Military and Civilian Technologies, MID company and Waxman Govrin Engineering.
“There is a commitment to take the sludge from the sea and start to make it in the ground process for land,” said Meir Carmel, director of both DAN-VIRO and CRM Military and Civilian Technologies, during a tour of the facility on Tuesday.
“This is the first such system in the Shafdan, which in the beginning will take 15% of the sludge.”
Meir noted that until now, that the only solution for all of the sludge produced at the plant has been “dumping [it] into the Mediterranean Sea” through a 5-km. pipe.
“It’s against what we call the Mediterranean Barcelona treaty,” Meir added, referring to the Barcelona Convention for the Protection of the Mediterranean Sea Against Pollution, signed in February 1976.
Leading a tour in the facility on Tuesday, Meir gestured from the wastewater plant to the ground, pointing to concealed pipes that carry the Shafdan sludge to the treatment facility – what Meir called “the blending house” – where the mud is emptied into a “special mixer that we brought in from the States.”
Into that same mixer then come the soil “additives,” limestone and fly ash collected from Israeli power plants, whose quantities are controlled by computers that sit below the sludge churners.
“We can arrange the ratio between the additives and the sludge according to what required end prod we need. It’s very flexible,” Meir said, noting that depending on who is receiving the soil, the customer may prefer different concentrations of limestone or fly ash.
“You have three ingredients – you have sludge, fly ash and limestone all coming together and being combined,” said Timothy Kasmoch, CEO and president of N-VIRO International Corporation, who had come to Israel to observe the Israeli plant in its pilot stage. “It’s a recipe of combining by-products to make beneficial reused product.”
Meanwhile, because the limestone (calcium carbonate) and water have an immediate exothermic reaction that raises the temperature 50 to 60 degrees Celsius, no additional energy is needed from outside sources to pasteurize the sludge – to eliminate any pathogens, according to Meir.
Organic metals, however, are preserved because “this is very, very important to agriculture,” added Lior Abukasis, the plant manager.
The entire mixing process takes an average of five to 10 minutes, and the machine has the capacity to mix 50 tons of sludge per hour, Meir said.
Eyeing a garbage bin filled with already produced soil samples, Kasmoch said “this is the best part,” as he began running his bare hands through the “clean” dirt, which he called “a full package of nutrients” and an ideal fertilizer.
“They say you can put it in a coffee pot and perk water through it – it’s that safe,” Kasmoch added, noting that he had not tried this. “The N-VIRO process does achieve Class-A stabilization, which is a complete elimination of any pathogenic organisms, anything in sludge that could be harmful. When we finish the process, this is a safe material.”
After remaining in the mixing facility 24 hours for quality testing, the end product rides on a horizontal conveyor belt to storage silos before making its way to a truck, which will cart it to its final destination.
Loading the trucks in the garage – which smelled strongly from what Meir and Kasmoch said was ammonia – takes about 15 to 20 minutes, and each truck can take up to 32 tons, Meir said.
“To convert sludge into fertilizer is very good,” said Dr. Raya Vulkan, laboratory manager at GILAT Field Service Laboratory, who studied the reuse of organic wastes like sewage sludge in agricultural soils as part of her doctoral degree at Ben-Gurion University.
While Vulkan could not comment on the DAN-VIRO project directly, she said that sewage sludge has the potential to be an “excellent fertilizer” in Israel’s farms – but not without limits.
“It should be limited on several points,” Vulkan added.
“There should be a process of getting rid of the pathogens and there could be a problem of phosphorous and heavy metals” – both of which DAN-VIRO staff guarantee they are eliminating.
Meir hopes that the current process will soon be extended further, with greater quantities of sludge becoming soil in the near future.
“If you take about [two-and-ahalf] of [the mixing facilities] you can process all the sludge of the Shafdan,” Meir said, explaining that the Shafdan puts out about 250,000 tons of sludge per year – 10% of Israel’s total sludge – and that each of these units has the total capacity to process about 100,000 tons annually.
In its pilot stages, the current unit won’t be working to full capacity. The mixer, for the first few months, is only doing one shift per day, and will increase throughout this period until it reaches 15% of the Shafdan sludge, the current amount approved for processing by the government, according to Meir.
The other 85% will continue to be dumped into the Mediterranean Sea, until the country makes a decision about what to do with it, Meir said.
“That’s a big debate,” he continued. “The government is now discussing whether to take a few technologies, or if this pilot is successful and there is no problem, then in a short time [we could potentially] enlarge the capacity to cover the whole 100,000 tons per year or even more, all 100% of the Shafdan sludge.”
If granted the authority by the government, Meir said that the plant would be able to build additional equipment within a year.
“It’s much easier – the initial development process was a decade,” Kasmoch agreed.
“Now that we’re here it’s a perm installation that’s much easier to expand. We believe it’s going to be much easier to introduce our N-VIRO fuel technology to really utilize a complete solution.”
N-VIRO plants in Toledo, Ohio, and Daytona Beach, Florida – where 75,000 and 250,000 tons of N-VIRO soil are produced annually – are also producing biomass fuel as well, made from organic wastes blended with coal or petroleum coke and burned as a coal substitute in coal-fired plants.
DAN-VIRO is hoping to do the same soon. Meir said he is now working with the Israel Electric Corporation to begin using sludge by-products as a green fuel for Israel’s coal power plants.
“It’s a further enhancement of what we have here today,” Kasmoch said. “That product can be further used for the generation of electricity and again it stays in the same category of creating safe, alternative, renewable energy.”
Kasmoch was enthused to have an Israeli plant as its first foreign franchise, as he sees the country as very forward-thinking in terms of renewable energies.
“It often feels as though in countries such as Israel you see an overwhelming acceptance for green and renewable and alternative technologies,” he said. “It almost feels sometimes that it’s more accepted in Israel than it is in the United States.”
Since a decade ago, when CRM Military and Civilian Technologies manager Yoram Malchi first approached N-VIRO about using the technology, Kasmoch said it has been “a successful partnership,” one that he hopes to soon replicate in other countries.
http://www.jpost.com/Sci-Tech/Article.aspx?id=216373