Newest articles and comments on The Sacramento Press written by David Prinzing

David Prinzing on "The future of news"

2009-03-24T00:42:15Z

I agree with Dave Winer that anyone can be a journalist today. The problem is that not all voices have equal merit, and a lot of the commentary is simply uninformed or misinformed noise. Consequently, I like the reputation-based credibility systems used by sites like Slashdot. They do a good job of filtering the noise.

David Prinzing on "Unsustainable Waste Disposal Practices"

2009-02-03T01:46:20Z

Hi, George! I think we agree on the Zero Waste goal. I'm all for the highest-and-best use of atoms; that's a basic tenet for our business. As a friend of mine in the Sierra Club says, "waste is a verb!" However, like many in reputable environmental organizations, I don't think we can really achieve zero waste without implementing some environmentally-responsible conversion technology. I believe we've found that technology. The greenaction report you're citing is rife with errors, mostly in logic and relevance. They make the mistake of assuming that all waste-to-energy technologies and facilities are the same, drawing connections between our proposed facility and other completely different facilities. That's why I wrote the first article in this storyline. If you're a chemical engineer, and you look at what I described, you'll reach the same conclusion as the Sacramento Municipal Air Quality Management District (they reviewed our reference design). In the workshop on January 15, they presented their conclusion: "no toxic emissions, but if you build it larger than a certain size, you'll need to get emissions credits for NOx (smog) and particulate matter". If you're willing to delve into the details, I think you'll find that there really are environmentally-responsible and financially-sound waste-to-energy processes available.

Unsustainable Waste Disposal Practices

2009-01-31T01:40:23Z

On January 15th, during a technical workshop that was poorly attended by the public and local media, the Sacramento City Council voted on a proposal that could wind up affecting the citizens of Sacramento for many years to come. The Council voted to table the City’s yearlong effort to replace the costly and environmentally detrimental practice of trucking Sacramento’s non-recyclable municipal solid waste (MSW) over the mountains to a landfill east of Reno, Nevada with a sustainable, less costly and more environmentally friendly waste-to-energy (WTE) approach.

Our Sacramento-based company, U.S. Science & Technology, submitted a proposal that was ultimately selected from among 11 responses to the city’s request for proposals. We were obviously disappointed in the Council’s decision to table any further action on this matter for the time being due to their concerns with the City’s handling of the vetting process. However, we remain committed to helping the City find alternative solutions to trucking and landfilling 400 tons of garbage each day. We also believe this can be done in a way that delivers significant economic benefits to Sacramento in the form of hundreds of jobs, substantial corporate tax revenues and millions of dollars in savings to ratepayers. Not a bad “green” deal in the midst of an economic crisis.

As many readers likely recall, over a year ago the City Council requested alternative proposals to the current unsustainable arrangement of shipping our non-recyclable trash to landfills. Understanding the city’s environmental and economic objectives, USST responded to the request with a proposal to implement a WTE facility using a state-of-the-art high-temperature gasification technology. This environmentally friendly and sustainable approach for disposing of the City’s municipal solid waste was approved time and time again by the City Council.

However, as the process unfolded, it became clear that some were unhappy with the process itself and there were a litany of city political concerns at play behind the scenes. All of this eventually led to the unfortunate tabling of the proposal.

We are engineers and scientists, not politicians, so it’s difficult for us to be certain exactly how and why this effort became so politicized and eventually got derailed. However, as a Sacramento-based company and as private citizens of this great city, we are concerned about what hasn’t been derailed: the trucking of this massive amount of non-recyclable waste to landfills over the mountains. We’ve presented an approach that would end this practice, to the benefit of the City, ratepayers and the environment. A high-temperature gasification WTE facility represents a scalable integration of proven technologies that, taken together, represents a practicable, safe, and efficient solution. The high-temperature gasification technology proposed by USST is proven, offers no financial risk to Sacramento, and is now being touted by many experts around the world as the best available technology for 100% conversion of garbage to commercial products like electricity and transportation fuels.

In fact, in an uncertain economic climate and in the midst of California’s unprecedented budget crisis, the proposed WTE facility would afford many benefits to the City:

A savings of millions of dollars for Sacramento citizens, notably on the trucking costs to Nevada;
The potential generation of substantial amounts of tax revenue for the city;
The creation of hundreds of new jobs throughout the conception, construction, and operation of the facility;
Assistance in helping the City meet its stated “green initiative” objectives; and
Quantifiable reduction of green house gas emissions and waste.

We are a local company of engineers, scientists and business leaders committed to environmental solutions in the waste-to-energy sector. We continue to offer a solution that we sincerely believe would be effective, environmentally and economically beneficial, and would present absolutely no financial risk to the City of Sacramento.

But regardless of the solution, Sacramento and its residents should not and cannot ignore the issue at hand. We hope the City Council puts this issue back at the forefront of the City agenda. In the meantime, we will continue exploring ways to help the city meet its environmental and economic standards while also developing and delivering a feasible solution to the unsustainable practice of landfilling 400 tons of Sacramento’s non-recyclable waste each and every day.

David Prinzing on "Inside out-sourcing"

2009-01-11T22:32:52Z

This is a fantastic article... quite poignant. And I'm observing here that it's not being published in the Bee. With respect to journalism and the influence of putting news on a dead tree, I have to disagree. I read everything with a grain of salt... including newspapers like the Bee. One of the things I love about the Economist newspaper out of Britain is that they don't pretend to not have an opinion or a point of view. It's evident in every article, and I'm okay with that. I think it takes a certain humility and sense of integrity to recognize that. I find it interesting also that my favorite newspaper is from Britain! It says something about the world we live in today. Digital communications technologies have broken the local monopoly on news. Every local newspaper today competes with every news source around the world (on the Internet) in every language that the reader speaks/reads. Local news sources should be experts in local news, and they should make that available to anyone who has an interest. I use RSS feeds keyed off of Google News searches for key words that I'm interested in, and these searches turn up interesting stories for me from some of the most obscure places. Example: did you know that the City of Grand Forks, ND is spending $230/ton on their recycling program? I wonder what we're spending? Is it worth it? I like what the Internet is doing for news, but we clearly need a new business model for journalism. Perhaps the Sacramento Press is a step in the right direction?

David Prinzing on "Sacramento Waste-to-Energy Facility"

2008-12-07T01:31:28Z

Greg, thanks for the link to the Sacramento Bee article. You can consider my article here to be a "counterpoint". I'm obviously a little biased, because I'm the Chief Engineer for USST, but I'm also the most informed on the technical details of what we're actually proposing. This article was intended to address a lot of misinformation and speculation that has been circulated in the Bee. Terri Hardy, the Bee reporter, has been covering a very technical subject without ever bothering to talk to me. My paragraph above on baseless comparisons is directed specifically at Bradley Angel and GreenAction. The two commercial plants they referenced used a different technology from a different provider, and the technical differences are very important. The comparison is as unfounded as their comparisons to old incinerators. SMUD is similarly uninformed. The energy efficiency question is a myth. It's not magic; it's chemistry. The analytical report from Juniper Consultancy Services referenced above shows that the plasma torches consume only 2% of the chemical energy coming in with the waste. Also, as reported above, the total plant consumes only 20% of the total electricity produced; 80% is available for sale. We're offering to sell the renewable energy to SMUD, but they need to make a competitive offer; they're not the only power producer we could sell to. SMUD doesn't support our proposal because they have their own proposal. They were one of the eleven parties submitting proposals in response to the RFQ, and theirs was not selected because it didn't meet the City's goals outlined above. In this sense, SMUD is one of our competitors. They have a political advantage over us though; they have an employee (Steve Cohn) on the City Council. For his day job, he's an attorney for SMUD. After recusing himself all year because of his obvious conflict of interest, he declined to do so in the last council meeting (November 6th) and came out fighting. Somehow the Bee seems to have missed that detail in their story. And, yes, USST has reimbursed the City for their travel expenses.

David Prinzing on "Sacramento Waste-to-Energy Facility"

2008-12-07T01:29:13Z

Thanks, Ben. I heartily agree. Can we call this "News Media 2.0"? Political status: with the recent mayoral transition and the holiday season, things are a little quiet right now. City staff are using the time to address questions raised by Council Members in the last City Council meeting. I think we can expect to see it make the agenda again sometime after the holidays.

Sacramento Waste-to-Energy Facility

2008-12-05T19:04:16Z

In 2007, the City of Sacramento generated an average of 750 tons/day of solid waste. About 348 tons/day (46%) of this was recycled, leaving 402 tons/day to be trucked across the Sierra Nevada mountains and buried in the desert at the Lockwood Regional Landfill in Sparks, Nevada. The City, consistent with its sustainability initiative, has been exploring more environmentally sound alternatives for the unrecycled portion of the waste, including the prospect of converting it into energy and other useful products. On August 24, 2007, the City issued a Request for Qualifications (RFQ) to attract a development partner to build, own, and operate a resource recovery and waste-to-energy facility in Sacramento that would meet five specific goals: (1) be environmentally friendly and reduce greenhouse gas emissions; (2) be economically viable and cost-neutral to rate-payers; (3) leave little or no residuals requiring treatment or landfill disposal; (4) continue the City's existing recycling program; and (5) utilize a proven technology at a commercial scale.

Eleven companies responded to the RFQ, proposing a total of five different technologies. The City then formed an independent, cross-functional committee to review the RFQ responses and recommend a development partner to move forward with. The committee was comprised of staff from the City Manager's Office, the Solid Waste Division, the City Attorney's Office, the Sacramento County Department of Waste Management and Recycling, and professors from the California State University College of Engineering. In November 2007, the committee determined that the plasma gasification technology proposed by US Science & Technology (USST) would best meet the City's goals indicated above. On February 26, 2008, following further research and due diligence, the City staff recommended and the City Council unanimously approved the project concept and awarded USST an exclusive right to negotiate Principles of Agreement with the City for the development of a waste-to-energy project. The City Staff's Report to Council provides more detail on the project and the rationale for selecting USST. This article describes the technology proposed and its environmental impacts and benefits.

The specifics of the technology, and how it's implemented, are incredibly important. Beneficial outcomes and environmental challenges are entirely dependent on the composition of the feedstock (garbage, in this case) and the specific chemical processes employed. Some comparisons have been made between our process and other technologies (e.g. plasma gasification and incineration) that are completely baseless and without fact; the processes employ different chemistry and yield very different results. Even technology comparisons within the field of plasma gasification can yield very different results, depending on the design of the process equipment and the specific chemical process steps employed. This article intends to make our proposed process more clear, so that useful comparisons can be made.

The "How Stuff Works" web site has an introductory article on plasma gasification that can be helpful for understanding the technology in general. The most detailed public description of the process USST is proposing for Sacramento is provided in an independent analytical report by Juniper Consultancy Services, Ltd. It provides a candid, in-depth examination of the technology provided by Alter NRG and Westinghouse Plasma Corporation, including emissions data from existing facilities. It is important to note, however, that the system design proposed by USST (and reviewed in the analytical report) makes significant improvements compared to the design of the existing facilities.

The waste-to-energy facility proposed for Sacramento includes three major sections: (1) gasification, (2) syngas cleaning, and (3) power generation. The plasma gasifier uses plasma torches with an external energy source (electricity) to heat the waste to very high temperatures in an oxygen-starved atmosphere (less oxygen than is needed for complete combustion). The chemical bonds in the waste material are broken down and very simple molecules are formed: carbon monoxide (CO), hydrogen (H2), nitrogen (N2), water (H2O), hydrochloric acid (HCl), etc. This mixture of primarily carbon monoxide and hydrogen gases is often called synthetic gas, or "syngas", and it exits the reactor at about 1600 degrees Fahrenheit. The inorganic materials in the waste flow out the bottom of the gasifier as an inert volcanic glass and liquid metal, in two separate phases, at about 3000 degrees Fahrenheit. However, some of the more volatile metals, such as mercury (Hg), lead (Pb), cadmium (Cd), and zinc (Zn), are vaporized and exit the gasifier with the syngas. These metals are removed in the syngas cleaning stage, along with hydrochloric acid (HCl) and sulfur compounds, namely carbonyl sulfide (COS) and hydrogen sulfide (H2S).

The syngas cleaning section of the facility is focused on cleaning the syngas so that it has a purity about like that of natural gas. This is done to protect human health, the environment, and the most expensive piece of equipment in the facility: the gas turbine. The syngas cleaning section has multiple operations, each designed for a specific purpose. The first step is a venturi scrubber, which ensures thorough mixing of process water and syngas. This step, along with the following step, a spray tower, are focused on rapidly cooling the syngas and capturing particulate matter and hydrochloric acid (HCl). Sodium hydroxide (NaOH) is added in the spray tower to neutralize the acid and form sodium chloride (NaCl), also known as regular table salt. The syngas is then sent to a wet electrostatic precipitator as a "polishing" step for further removal of sub-micron particles. At this point, the syngas is fully saturated with moisture (100% relative humidity). It is sent to a condenser, where the syngas temperature is further reduced to about 68 degrees Fahrenheit, and on to a compressor, which raises the pressure to about 350 psig and condenses even more moisture out. Process water from these steps is sent to an on-site water treatment plant, where the water is purified and reused in the facility (and incidentally, the facility is slightly net-positive in water production; it comes in with the solid waste and is formed in some of the chemical reactions). The cooled, compressed syngas is then sent through a pair of activated carbon beds for 99.75% removal of any mercury (Hg) that may be present in the syngas. The final step in the syngas cleaning section of the facility is focused on removing sulfur. This technology is commonly used to remove sulfur from natural gas, and it involves both a carbonyl sulfide (COS) hydrolysis reaction to convert COS to hydrogen sulfide (H2S), and a subsequent step wherein the H2S is removed from the syngas and converted into elemental sulfur crystals. At this point, the syngas has been thoroughly cleaned and is ready for use as a fuel in the power generation section of the facility.

The power generation section of the facility is based on a conventional combined-cycle power plant. These are typically fueled with natural gas, and are some of the cleanest and most efficient power plants in existence. Just such a facility was recently built in Roseville; it began operation in 2004. Our facility would be fueled primarily with clean syngas; natural gas would be used as a supplemental fuel for start-up and shut-down of the gas turbine and to even out natural variations in the real-time production of syngas which would be expected with the variability in municipal solid waste. The fuel gas is burned in a gas turbine, where the expanding gases spin the turbine and power an electric generator. The hot exhaust from the gas turbine is directed to a steam generator, which produces steam that drives a steam turbine and another electric generator. An oxidation catalyst would be used to remove any trace amounts of carbon monoxide (CO) that may remain in the exhaust, and Selective Catalytic Reduction (SCR) would be used to remove nitrogen oxides (NOx, or smog) before sending the exhaust up a stack. In a generic reference design for a 750 ton/day facility similar to the one described here, the gas turbine generator produces 44 MWe, the steam turbine generator produces 22 MWe, and the facility uses 13 MWe to run the plasma torches, motors, etc. In that design, 80 percent of the electric power produced (53 MWe) is available to be put on the electric grid, and 20 percent (13 MWe) is used internally to run the plant. The total capacity of the facility proposed for Sacramento has yet to be determined. The emissions would be about what you would expect for a natural gas-fired combined-cycle power plant, except that most of the carbon dioxide (CO2) would come from a renewable energy source: municipal solid waste.

The solid residuals from the plasma gasifier (metal and glass) would be recycled. The glass portion is particularly interesting, in that it can be used to manufacture higher-valued products, such as rock wool, stone tile, and other construction materials. The solid residuals from plasma gasification of municipal solid waste have been proven to be non-toxic; they easily pass the EPA's Toxicity Characteristic Leaching Procedure (TCLP). In fact, plasma vitrification is sometimes used specifically to render ash from municipal solid waste incinerators non-toxic.

Sometimes innovative, game-changing technologies seem too good to be true, but a review of recent history proves that innovative technologies can and do change our lives for the better. The primary challenge for a facility like this is the capital cost to build it. It's very expensive, and investors need assurance that there will always be a waste stream for the facility so that the long-term investment can pay for itself. That's why a long-term waste supply agreement is so important; it makes the funding possible. And we're finding that there is a tremendous level of interest in the financial community for funding renewable energy projects. If the City will supply the waste, we can make it happen.

About the author: David Prinzing is Vice President and Chief Engineer for US Science & Technology. He is a registered Professional Engineer (Chemical Engineer) in the States of California and Washington, and has more than 20 years of diverse technology experience, including combustion, chemical, nuclear, and environmental engineering.