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Our Favorite Toxic Chemical: Nitrate

Today’s post is from guest blogger Melissae Fellet, a science writer based in Santa Cruz, California, and was written for the “Our Favorite Toxic Chemicals” blog carnival hosted by Sciencegeist.

Feeding my vegetable garden so it will feed me

I’m eager to grow some of my own food this summer, so I planted a vegetable garden in pots on my porch. Since my previous gardening experience consists of ignoring my plants, learning some gardening tips was a must.

I hope my plants look this healthy in a few weeks! (Image by flickr user despi88)

Like humans, plants need food, too. Those nutrients come from boosts of nitrogen, phosphorus and potassium-containing fertilizer. But plants need help getting their roots on some nutritious nitrogen when that fertilizer contains kelp, alfalfa, crushed bones, chicken poop and ground feathers, like the organic stuff I put in my garden.

Some of those ingredients contain nitrogen as ammonia, which plants can absorb directly. Proteins are another source of nitrogen. Bacteria in the soil separate proteins into amino acids. Other microbes chomp the nitrogen off the amino acids as ammonia. And super-specialized bacteria eat ammonia and release the nitrogen as nitrate (NO3-). Nitrate is great plant food, too, because it zips through the soil straight to a plant’s roots.

This biological nitrogen transformation is slow, so farmers may feed their plants a nitrate-containing fertilizer to speed growth. That’s a touchy subject in the agricultural areas near my home in California.

About 10 percent of 2500 public water wells tested in the Tulare Valley and Salinas Valley exceed the state limits of 45 mg nitrate per liter of water, according to a report prepared for the state water department last March. The majority of the nitrate in groundwater — about 96% — washes off cropland, the report found.

Nitrate takes time to trickle from a field into the groundwater, so most of that contamination is due to decades of past farming in the area. But if the nutrient pollution trend continues, 80% of the people living in those valleys could be drinking nitrate-laden water by 2050.

Nitrate becomes harmful when our bodies convert it to its chemical cousin, nitrite (NO2-). Nitrite transforms the iron in our blood so that it can no longer carry oxygen. Enough altered iron — 10 percent of the hemoglobin in your blood — causes breathing troubles especially in infants and pregnant women. Higher concentrations can lead to suffocation.

Still, it takes a lot of nitrate to harm a person. According to data from the World Health Organization [PDF], an average three-month old baby boy might have to drink about four liters of water contaminated with nitrate at twice the state limit to induce toxicity. An adult might drink up to 56 liters of the same water at once to get a fatal dose of nitrate.

Excess nitrate can be toxic to the environment, too. The nutrient washes into a Central Coast wetland, feeding microscopic algae until they grow into thick green mats that suffocate ponds and channels.

The UC Davis report says that fertilizer fees and improved groundwater monitoring can help protect drinking water. And policy changes are in the works for one part of the state. In March, the Central Coast Regional Water Control Board passed regulations to reduce nitrate-containing runoff from fields. These rules took three years to negotiate and they are still tangled in a lawsuit from growers.

Even without regulations, farmers can prevent nitrogen pollution by controlling the amount of fertilizer on the fields and feeding plants only what they can absorb. The state report also suggests using nitrate-laden ground water for irrigation. Plants absorb the nitrate from the water, and clean water returns to the aquifer.

Lacking a home nitrate test kit for my garden, I’ll choose organic fertilizer when it comes time to feed my plants again. That should give my plants a slow drip of nitrogen and hopefully prevent a build up of excess nutrients. I feed my plants nitrogen so they’ll be strong and healthy enough to produce food for me.

Bring on the orange carrots, yellow peppers and purple beans!

The Money in Dirt

Cleantech firms are sometimes criticized for pie in the sky thinking. Harvest Power, though, looks like a pretty down to earth company. It makes dirt*. Mind you, this is high quality dirt*.

Compost. Black Gold? Credit: Harvest Power

Late last week, Harvest Power said it had raised $110 million in a third round of venture capital funding. That’s a tidy sum for a messy business. Harvest is an industry that some call “organics management.” According to the firm’s website, it works at a community level to gather and re-use organic materials (food waste, lawn clippings, pieces of lumber). It produces mulches, organic fertilizer, and soil products using composting and anareobic digestion.

These technologies are not exactly new. But it seems that the value is in its system approach and its facilities. Harvest ties into local communities where organic materials are separated from the waste stream. In addition to recyling the waste into soil-related products – which it sells to local farmers and gardeners - its digestors produce renewable energy from biogas.

The biogas is used in combined heat and power plants, exported as pipeline-grade (i.e. purified methane) natural gas, or compressed gas to be used for transportation. High heat content materials like wood chips are also processed into fuel for use in industrial boilers.

According to PrivCo, a firm that tracks the finances of privately-held companies, Harvest can boast significant revenues (this contrasts the firm with some cleantech plays that go public before making any money from sales). Founded in 2008, it made close to $50 million last year and is expected to rake in $75-$100 million in 2012.

The financing will be used by the company to expand its reach. PrivCo reports Harvest is finishing two Canadian energy plants and has plans for waste to energy facilities in New Jersey and Florida.

* [update] Harvest actually produces soil, as The Phytophactor points out in his comment.

 

 

Spring Themes: Composting

[you can skip my musings and go straight to Alex's compostable plastics story!]

Today’s forecasted high temperature where I live in the Northeast is 78 degrees. That just doesn’t seem right. This time last year, we still had an impressive layer of snow which didn’t melt until sometime in April. [insert random thoughts of global warming, La Nina, and how yesterday was almost 20 degrees warmer than the forecast promised]

Over the weekend I took the opportunity to turn my compost pile. It’s got mostly kitchen scraps, a few bits of brown paper bag (worms love ‘em) and leaf litter. Home composting is both an art and a science – my pile had too much nitrogen and not enough carbon, so I added more dried leaves.

I also noticed a plastic spoon in the pile, normally a no-no. But this one was made of PLA, a plastic derived from corn that is supposed to be biodegradable. It still looked pretty new, though, mostly because my backyard pile cannot reach the high temperature and rabid microbial activity of an industrial scale composting operation.

If I lived in San Francisco (and today it feels like I do!) I would put the spoon and my kitchen scraps, and perhaps some lawn wastes into a compostable plastic bag and set it out to be picked up. This week’s issue of C&EN features an in-depth, fascinating story by Alex Tullo on how compostable plastic trash bags – plus disposable dinner ware – can enable cities to divert 50% or more of trash away from landfills.

From the story:

In a landfill, food scraps generate methane, a much more potent greenhouse gas than CO2. They also form acids that leech out of landfills. “If you ask all these cities what the largest component of their waste going to the landfill is, it’s food,” he says. “And what is one of the worst things to go to the landfill? It’s food. The only thing worse is hazardous waste.” [quote from Jack Macy, commercial zero-waste coordinator for SF Environment, San Francisco’s environmental department.]

Now think about your household’s waste. To reach San Fran’s goal of diverting 100% of municipal trash from landfills, it would have to be either recycled or composted. Plastics can be recycled, but if they get into the composting supply (like a random fork, or the trash bag holding the food waste) then you’ve already broken your system.

Biofuels from Seaweed

The concept of making biofuels from seaweed has been floating around as an idea for a while now, but this week there were a few real news items about it. Well, I consider it real news when it makes the cover of Science

.

Seaweed in your tank? Credit:
Melody Bomgardner

Following the theme that any ready source of carbon, not already used for something, is a prime target for biofuel prospectors, scientists are working to create microorganisms that can break down seaweeed alginates into sugar, and then make ethanol from it.

The microbe is our friend E. coli, and researchers at Bio Architecture Lab, a biofuel and renewable chemicals company in Berkeley, Calif. have added genes that allow E. coli to first break down alginates into smaller bits, digest those more sugar-like bits, and then spit out ethanol.  Unlike in the processes usually used for cellulosic ethanol, the Science article writers claim their bacteria can chomp seaweed without chemical or heat pre-treatment.

If seaweed as cover model isn’t convincing, a second seaweeed-flavored item announced this week is a new collaboration between enzyme maker Novozymes and an Indian seaweed company called Sea6 Energy. “The research alliance will use enzymes to convert seaweed-based carbohydrates to sugar, which can then be fermented to produce ethanol for fuel, fine chemicals, proteins for food, and fertilizers for plants,” says the press release. (I read that to mean the non-sugar portion would be made into food and fertilizer – if sugar can be made into protein I’m going to have to change my diet).

Here’s the benefits that the seaweed pushers are claiming: seaweed has a high sugar content (presumably after those enzymes get to working), they don’t require irrigation (ha! no kidding) or fertilizer, and of course, duh, they don’t take up cropland. Seaweed – also called macroalgae by some – can be raised and harvested without those fancy bioreactors used by algae-to-fuel operators.

Seaweed can, however, be a purpose-grown crop. In fact, Sea6 already has a supply chain set up for that, as do firms like the chemical company FMC that harvest and process seaweed for the food markets. Alginate and carrageenen are already big business helping to make your low-fat Ranch dressing taste creamy (see Call in the Food Fixers for more on seaweed in your food).

But what works for the high-margin food additives business may not be profitable for the lower-margin fuel industry. Still, it’s an idea that’s spreading.

Palm Oil Not Clean Enough for RFS, says EPA

The eco-bonafides of palm oil have been long debated, especially in Europe, and it looks like that cat fight may now move to the U.S. The general charge against palm oil is that plantations devastate rainforests and other native habitats that suck up CO2. That problem seems particularly relevant when palm oil is used to make biofuel; land use changes may undermine any benefit in reducing use of fossil fuels.

Palm oil tree. Credit: Wikipedia

EPA has put out a notice that palm oil biofuels (diesel) do not meet the agency’s standard for climate-change gas reduction in the Renewable Fuel Standard. At a minimum, a renewable fuel has to provide a 20% emissions savings, and biofuels from palm oil rate only as high as 17%.

EPA points out that 90% of palm oil comes from Malaysia and Indonesia, and that’s where it focused its analysis. In a note, EPA gives two examples of ways that palm oil production fails. “For example, palm oil production produces wastewater effluent that eventually decomposes, creating methane, a GHG with a high global warming potential. Another key factor is the expected expansion of palm plantations onto land with carbon-rich peat soils which would lead to significant releases of GHGs to the atmosphere.”

EPA has opened a comment period on this ruling, and palm oil producers in Malaysia and Indonesia are very likely to file protests. As reported in the  Business Times of Malaysia, that country is already threatening a trade war. The article also says that the EU has similar restrictions.

Palm oil growers who would claim the EPA is biased in favor of trade protectionism would enjoy some company with Chinese solar panel producers who are fighting back against dumping charges from some U.S. solar manufacturers.

 

A New Year for Biofuels

Fuel blenders are finding that the New Year is bringing a few changes to their business. Before Congress adjourned for the holidays, it opted not to renew the subsidies for putting corn ethanol into gasoline. Though the subsidy had become a fact of life – and added up to $6 billion last year – the fall of the corn regime was not unexpected.

This morning, NPR tried to answer the question of whether anybody would notice the difference, and according to their expert, energy economist Bruce Babcock at Iowa State University, most likely no one will. You can review the segment on the NPR website.

I don’t yet have a number for 2011 production of corn ethanol, but 2010 was a record year, according to the Renewable Fuels Association. U.S. refineries produced 13.23 billion gallons of the stuff. So bear that number in mind for my next item…

Totally aside from and unrelated to the generous corn ethanol subsidy that no longer exists, the EPA still requires the blending in of biofuels in its Renewable Fuels Standard, now in its second edition (RFS2). For 2012, EPA says blenders must include 8.65 million gallons of cellulosic biofuel* in their fuel mix. That will be equivalent to .06% of all renewable fuel produced in 2012. RFS2 says blenders will need to use 9.23% of renewable fuels in their blends in 2012 – most of that will still be corn ethanol.

EPA is tracking 6 cellulosic biofuel projects that are supposed to produce in 2012, and that is how it came up with the number. This is what EPA published at the end of December:

KL Energy Corp. is the only facility in the United States currently generating cellulosic biofuel RINs. American Process Inc., Fiberight, and ZeaChem all anticipate completing construction on their production facilities in late 2011 or early 2012 and plan to begin producing biofuel soon after their facilities are complete. INEOS Bio and KiOR are targeting April 2012 and mid 2012 for the start-up of their respective cellulosic biofuel production facilities. The variation in these expected start-up times, along with the facility production capacities, company production plans, and a variety of other factors have all been taken into account in projecting the available volume of cellulosic biofuel from each these facilities.

There are a couple of other projects in the works that are likely to be RFS2 candidates, but not this year. Poet has received a conditional USDA loan guarantee and is building a co-located plant (with corn ethanol) in Emmetsburg, Iowa – scheduled for completion in 2013. DuPont now has full ownership of what used to be DuPont Danisco’s cellulosic project. No word yet on when that plant will be constructed, but it will be in Nevada, Iowa.

*Edited 1/4/12 to state cellulosic biofuel rather than cellulosic ethanol. EPA anticipates that the largest cellulosic fuel producer will be KiOR, which will be making biodiesel and gasoline from cellulose at its plant in Columbus, MS. KiOR is the only project of the six planning to make anything other than ethanol.

 

 

Advanced Biofuels: pipedream or solid investment?

I read with much amusement this week two dueling editorials about advanced biofuels; one from the Wall Street Journal and the other - a reaction piece – from Biofuels Digest. One was pr0 and one against, I’ll let you strain your brain figuring out which was which.

Editorial boards have plenty of information to pick from to illustrate a variety of contentions – from advanced biofuels are a “march of folly” paid for with “an invisible tax paid at the gas pump” to biofuel as wise investment not just for government, but for companies like Shell and BP. Evidence for the former view: Range Fuels, which absorbed both grants and loans before succombing to the perils of scale-up engineering last week. Evidence for the latter would include Mascoma‘s joint venture with Valero Energy to build a 20 million gal per year cellulosic ethanol plant in Michigan. Valero will foot a good portion of the estimated $232 million bill to construct the facility.

The crux of the problem, as Cleantech Chemistry and many others have observed (including the National Academies) is that the type of advanced biofuels (i.e. fuel not made from food-like feedstocks such as corn sugar) called cellulosic ethanol has not achieved scale to date. (There are other, more lifecycle concerns, as well). Biofuel Digest editors point out that the larger proportion of advanced biofuels scaling up now are of a different sort- like biodiesel for example. In short, they point out there are multiple roads to get to the same place.

The Wall Street Journal, to its credit, does not politicize its arguments – it rightly notes that Range Fuel’s support came from programs created by the Bush administration. Meanwhile, Biofuels Digest points out that the CapEx on the Mascoma plant pencils out to $11 per gal of ethanol for the first phase. The plant may produce up to 80 million gal per year, however, and all the usual promises of cheaper production through scale are supposed to apply.

US Cleantech firms in white-knuckle mode

There has been one positive piece of news this week for the cleantech sector – Solazyme is part of a $12 million grant to supply the U.S. Navy with 450,000 gal of biofuel. Solazyme’s algal oil will be used along with used cooking grease to power a fuel plant run by Dynamic Fuels, a joint venture between Tyson Foods and Syntroleum. They’ll be making both renewable jet fuel and marine fuel. Press releases about the deal emphasize that it is the single largest biofuel purchase in government history.

Thank goodness cleantech has the government as a customer. Private industry customers haven’t panned out so well lately for battery firms like A123 Systems and Ener1, as reported this week in the Wall Street Journal. Major investments in battery manufacturing – supported in large part from Recovery Act funds – have been met with disappointing demand from electric-car makers. A123 Systems has scaled back its scale-up plans because its big customer, Fisker Automotive, has slowed its own plants due to technical problems. Meanwhile Ener1′s customer Think Global has filed for bankruptcy protection.

When C&EN wrote about the battery scale-up, a major concern at the time was that there would be more battery capacity than cars to put them in, and that seems to be the case for now.

Back to biotech, according to a Reuters report from Pike Research analyst Mackinnon Lawrence, the biofuels industry is very concerned that budget cutting in Congress will pull the rug out from programs that are helping companies bootstrap their way to cost parity with petroleum. Part of the problem is that industry’s promises to have commercial-scale production on line by this year  have not panned out. Cellulosic ethanol is the biggest disappointment, and so now attention is likely to switch to drop-in biofuels like renewable gasoline and renewable diesel. Or, even better, jet fuel.

DuPont’s Cellulosic Plans

DuPont has been digesting its acquisition of Danisco for a while now, and has sent out an update about what used to be called DuPont Danisco Cellulosic Ethanol – now shortened, as you might guess, to DuPont Cellulosic Ethanol. In a press release, DuPont says the effort will now be led by Steven J. Mirshak, who will scoot over from his position as president of DuPont Tate & Lyle Bio Products.

Field day visitors check out switchgrass at a farm in Vonore, Tenn. Credit: UT Institute of Agriculture, P. McDaniels

The firm is still planning to build a cellulosic ethanol plant in Nevada, Iowa. Like another Iowa cellulosic ethanol plant being built by corn ethanol producer Poet, DuPont also is pushing a parallel effort to gather up the corn stover needed as a feedstock. It is a part of something called the Stover Collection Project, with Iowa State University.

Meanwhile, back at the ranch, otherwise known as DuPont’s demonstration facility in Vonore, Tenn., the company “continues to make advancements” in preparation for scale-up, though we don’t learn what those are. Nearby, DuPont partner firm Genera Energy (which is connected to the University of Tennessee) is harvesting test fields of switchgrass. Genera held a recent field day where the company showed visitors the switchgrass varieties as well as the equipment used to harvest them.

We here at Cleantech Chemistry will be monitoring  progress toward large-scale production of cellulosic ethanol. As a recent report from the National Academies has pointed out, the U.S. is way, way behind  where it is supposed to be this year in producing the stuff.

Bad Biofuels Vibes, but no Break for Solar

Last week the National Academies released a report about the federal Renewable Fuels Standard – and the scientist-authors basically panned it from top to bottom. As a policy tool, the NAS said, the RFS is unlikely to work. They point out that production of cellulosic ethanol – the type of renewable fuel the policy is supposed to spur production and use of – still struggles to get off the ground.

As Jeff Johnson reported in this week’s issue, the government estimates this year’s haul of cellulosic ethanol will be a mere 6.6 million gal, far below the RFS target for 2011 of 250 million gal. The standard mandates a huge upswing in production of cellulosic ethanol – 16 billion gal by 2022 – at which point it would pass the amount of ethanol the country is supposed to get from corn. NAS points out what most folks would likely observe – that this goal would be very difficult to meet.

But NAS goes farther by questioning the green credentials of cellulosic ethanol. As a second-generation or advanced biofuel, cellulosic ethanol was supposed to be much better for the environment than corn ethanol, and certainly a vast improvement over fossil fuels. But, Johnson reports, the authors forecast major downsides from growing crops for biofuels including “the one-time release of greenhouse gases from disturbed biomass and soil may exceed future reductions of greenhouse gases expected as a result of the shift from gasoline to biofuels.”

Meanwhile the solar saga continues. The Washington Post is still digging into government e-mails related to the Obama administration’s dealings with Solyndra – the defunct solar firm that benefited from a $535 million loan guarantee. It looks like there will be plenty of material to keep this topic open for a while – as I predicted – and the issue will continue to cast a shadow over government actions in the green manufacturing sector.

That said, the U.S. will soon become a leading destination for solar installations, as I report in this week’s issue. This is a positive development in terms of the country’s ability to generate renewable power. But it comes at a price – the low, low cost of crystalline silicon solar cells, mainly imported from China, is likely to blast a hole through a portion of the U.S. solar manufacturing base.

If I were to put on my policy hat (first I’d have to dust it off and remove some cobwebs), I’d be pondering a few questions this week. Is it more important for the U.S. to be able to ramp up its capacity to generate renewable solar power by installing cheap solar modules or should the U.S. try to spend more money to spur more solar cells, panels, and modules to be made in this country? Right now, those two goals are not aligned.

And what should the future of cellulosic ethanol be? If there are questions about the environmental benefit of a production system that can generate 16 billion gal of the stuff, how should we begin to answer those questions? Biofuel backers say we should move forward and get facilities and feedstocks going and work to improve the climatic impacts as part of the learning curve. Critics say we should acknowledge the trade-offs up front, which may minimize the role of cellulosic ethanol.