Type | Private |
---|---|
Industry | Waste-to-Energy Gasification |
Founded | 2004 |
Founder | William Davis |
Defunct | apparently around 2014 |
Headquarters | , USA |
Key people | Walt Howard (CEO) Mark Prendergast (CFO) |
Number of employees | 28 (2009) |
Ze-gen, Inc. was a renewable energy company developing advanced gasification technology to convert waste into synthesis gas. Founded in 2004, Ze-gen was a venture-backed company based in Boston, Massachusetts.
The company aimed to develop innovative technological solutions to reduce landfills and find beneficial use for waste material by converting waste to energy and nutrients, using advanced gasification.
Today Ze-gen appears to be defunct, and the company website was taken down in 2014. [1]
The liquid metal gasification process begins with feed material entering the gasifier through a gas-tight airlock into a refractory-lined vessel containing liquid copper, which is held at about 2200 °F. Material entering into the liquid metal gasifier undergoes a series of thermo-chemical reactions, which are auto-thermal under stable operating conditions. Initially, pyrolysis occurs and volatiles are driven into the headspace of the gasifier. In the subsequent gasification reaction, hydrogen (H
2) and carbon monoxide (CO) are favored as final products, along with carbon dioxide (CO
2) and a small amount of methane (CH
4). This product gas is called synthesis gas, also known as syngas.
The inorganic constituents, which are generally lighter than liquid metal, form a slag layer on top of the liquid metal bath and are removed as a vitrified non-leachable slag byproduct. The slag is either recycled or disposed of as an industrial by-product. While some metals and oxides present in the feedstock accumulate in the liquid metal bath, others will exit as vapor and are captured in the gas cleanup process.
The syngas produced can be used for several different end-use applications including: steam generation, electricity production, making industrial hydrogen gas, as chemical building blocks for synthetic diesel or ethanol, synthetic natural gas, methanol, or as a chemical feedstock into a variety of industrial processes.
Ze-gen's demonstration facility is colocated with a processing facility owned by New Bedford Waste Services, LLC in New Bedford, Massachusetts. [2] The facility was built to test the key parameters of the gasification process in order to more fully understand the chemistry of the system and the operating parameters. The plant became operational in November 2007, and Ze-gen achieved target synthesis gas quality in June 2008. [3] The data and analysis collected during the Phase I testing helped to inform modifications and upgrades in the facility. Phase II testing began in September 2009. As of June 2011, the demonstration facility has logged over 4200 hours of operation, including 30 days of consecutive runtime. [4]
Ze-gen plans to develop its first commercial facility in Attleboro, Massachusetts. [5] The proposed facility is to be located within the Attleboro Corporate Campus, a former Texas Instruments manufacturing facility and now the home to a number of businesses. Through the conversion of 44,000 tons of specific waste streams annually, the syngas produced at the facility will be used to generate approximately 7MW of alternative energy. The thermal and electrical power will be sold to tenants within the corporate campus, allowing the campus to reduce its reliance on fossil fuels. [6] In April 2011, Ze-gen announced its decision to suspend its project in Attleboro in order to focus on developing its commercial facility project at a site with stronger energy markets and one that's more receptive to alternative energy development. [7]
As of 2009, Ze-gen has received $30 million in funding from sources including: Omar Zawawi Establishment, Flagship Ventures, VantagePoint Venture Partners, and Massachusetts Technology Development Corporation. [8]
Syngas, or synthesis gas, is a fuel gas mixture consisting primarily of hydrogen, carbon monoxide, and very often some carbon dioxide. The name comes from its use as intermediates in creating synthetic natural gas (SNG) and for producing ammonia or methanol. Syngas is usually a product of coal gasification and the main application is electricity generation. Syngas is combustible and can be used as a fuel of internal combustion engines. Historically, it has been used as a replacement for gasoline, when gasoline supply has been limited; for example, wood gas was used to power cars in Europe during WWII. However, it has less than half the energy density of natural gas.
Gasification is a process that converts biomass- or fossil fuel-based carbonaceous materials into gases, including as the largest fractions: nitrogen (N2), carbon monoxide (CO), hydrogen (H2), and carbon dioxide (CO2). This is achieved by reacting the feedstock material at high temperatures, without combustion, via controlling the amount of oxygen and/or steam present in the reaction. The resulting gas mixture is called syngas or producer gas and is itself a fuel due to the flammability of the H2 and CO of which the gas is largely composed. Power can be derived from the subsequent combustion of the resultant gas, and is considered to be a source of renewable energy if the gasified compounds were obtained from biomass feedstock.
The Fischer–Tropsch process is a collection of chemical reactions that converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons. These reactions occur in the presence of metal catalysts, typically at temperatures of 150–300 °C (302–572 °F) and pressures of one to several tens of atmospheres. The process was first developed by Franz Fischer and Hans Tropsch at the Kaiser-Wilhelm-Institut für Kohlenforschung in Mülheim an der Ruhr, Germany, in 1925.
Coal gasification is the process of producing syngas—a mixture consisting primarily of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), natural gas (CH4), and water vapour (H2O)—from coal and water, air and/or oxygen.
A waste-to-energy plant is a waste management facility that combusts wastes to produce electricity. This type of power plant is sometimes called a trash-to-energy, municipal waste incineration, energy recovery, or resource recovery plant.
Coal liquefaction is a process of converting coal into liquid hydrocarbons: liquid fuels and petrochemicals. This process is often known as "Coal to X" or "Carbon to X", where X can be many different hydrocarbon-based products. However, the most common process chain is "Coal to Liquid Fuels" (CTL).
Synthetic fuel or synfuel is a liquid fuel, or sometimes gaseous fuel, obtained from syngas, a mixture of carbon monoxide and hydrogen, in which the syngas was derived from gasification of solid feedstocks such as coal or biomass or by reforming of natural gas.
In industrial chemistry, black liquor is the by-product from the kraft process when digesting pulpwood into paper pulp removing lignin, hemicelluloses and other extractives from the wood to free the cellulose fibers.
Bioconversion, also known as biotransformation, is the conversion of organic materials, such as plant or animal waste, into usable products or energy sources by biological processes or agents, such as certain microorganisms. One example is the industrial production of cortisone, which one step is the bioconversion of progesterone to 11-alpha-Hydroxyprogesterone by Rhizopus nigricans. Another example is the bioconversion of glycerol to 1,3-propanediol, which is part of scientific research for many decades.
An integrated gasification combined cycle (IGCC) is a technology using a high pressure gasifier to turn coal and other carbon based fuels into pressurized gas—synthesis gas (syngas). It can then remove impurities from the syngas prior to the power generation cycle. Some of these pollutants, such as sulfur, can be turned into re-usable byproducts through the Claus process. This results in lower emissions of sulfur dioxide, particulates, mercury, and in some cases carbon dioxide. With additional process equipment, a water-gas shift reaction can increase gasification efficiency and reduce carbon monoxide emissions by converting it to carbon dioxide. The resulting carbon dioxide from the shift reaction can be separated, compressed, and stored through sequestration. Excess heat from the primary combustion and syngas fired generation is then passed to a steam cycle, similar to a combined cycle gas turbine. This process results in improved thermodynamic efficiency compared to conventional pulverized coal combustion.
Waste-to-energy (WtE) or energy-from-waste (EfW) is the process of generating energy in the form of electricity and/or heat from the primary treatment of waste, or the processing of waste into a fuel source. WtE is a form of energy recovery. Most WtE processes generate electricity and/or heat directly through combustion, or produce a combustible fuel commodity, such as methane, methanol, ethanol. or synthetic fuels.
Plasma gasification is an extreme thermal process using plasma which converts organic matter into a syngas which is primarily made up of hydrogen and carbon monoxide. A plasma torch powered by an electric arc is used to ionize gas and catalyze organic matter into syngas, with slag remaining as a byproduct. It is used commercially as a form of waste treatment and has been tested for the gasification of refuse-derived fuel, biomass, industrial waste, hazardous waste, and solid hydrocarbons, such as coal, oil sands, petcoke and oil shale.
Second-generation biofuels, also known as advanced biofuels, are fuels that can be manufactured from various types of non-food biomass. Biomass in this context means plant materials and animal waste used especially as a source of fuel.
Chemrec was a Stockholm, Sweden corporation that developed technology for entrained flow gasification of black liquor and certain types brown liquor for production of biofuels from the resulting syngas.
Plasma gasification is in commercial use as a waste-to-energy system that converts municipal solid waste, tires, hazardous waste, and sewage sludge into synthesis gas (syngas) containing hydrogen and carbon monoxide that can be used to generate power. Municipal-scale waste disposal plasma arc facilities have been in operation in Japan and China since 2002. No commercial implementations in Europe and North America have succeeded so far. The technology is characterized by the potential of very high level of destruction of the incoming waste, but low or negative net energy production and high operational costs.
Chinook Sciences is a US and UK based technology company that specializes in waste to energy and metal recovery.
Syngas to gasoline plus (STG+) is a thermochemical process to convert natural gas, other gaseous hydrocarbons or gasified biomass into drop-in fuels, such as gasoline, diesel fuel or jet fuel, and organic solvents.
Coal gasification is a process whereby a hydrocarbon feedstock (coal) is converted into gaseous components by applying heat under pressure in the presence of steam. Rather than burning, most of the carbon-containing feedstock is broken apart by chemical reactions that produce "syngas." Syngas is primarily hydrogen and carbon monoxide, but the exact composition can vary. In Integrated Gasification Combined-Cycle (IGCC) systems, the syngas is cleaned and burned as fuel in a combustion turbine which then drives an electric generator. Exhaust heat from the combustion turbine is recovered and used to create steam for a steam turbine-generator. The use of these two types of turbines in combination is one reason why gasification-based power systems can achieve high power generation efficiencies. Currently, commercially available gasification-based systems can operate at around 40% efficiencies. Syngas, however, emits more greenhouse gases than natural gas, and almost twice as much carbon as a coal plant. Coal gasification is also water-intensive.
Sierra Energy is a privately owned waste-to-energy gasification company. The company claims that its FastOx gasification technology can take virtually any trash and turn it into clean energy, without burning. Sierra Energy is a division of Sierra Railroad. It is headquartered at the Sierra Energy Research Park in Davis, California and its commercial facility is located in Monterey, California.,
Chemical looping reforming (CLR) and gasification (CLG) are the operations that involve the use of gaseous carbonaceous feedstock and solid carbonaceous feedstock, respectively, in their conversion to syngas in the chemical looping scheme. The typical gaseous carbonaceous feedstocks used are natural gas and reducing tail gas, while the typical solid carbonaceous feedstocks used are coal and biomass. The feedstocks are partially oxidized to generate syngas using metal oxide oxygen carriers as the oxidant. The reduced metal oxide is then oxidized in the regeneration step using air. The syngas is an important intermediate for generation of such diverse products as electricity, chemicals, hydrogen, and liquid fuels.