Hyperion XP-1 is proof that hydrogen power reigns supreme
Blackstone Green Energy develops process for converting zinc ore into green hydrogen
Blackstone Green Energy has developed a patent-pending method for producing and distributing green hydrogen. This document provides an overview of the technology.
In this white paper, Blackstone Green Energy discusses:
Provisional patent application of Blackstone Green Energy covering production and distribution of green hydrogen.
Provisional patent application of Blackstone Green Energy covering the Blackstone Method of green hydrogen production.
Excerpt from Scientific Investigations Report 2016-5089-C from the U.S. Geological Survey showing "High Potential with Certainty Level D" for porphyry-related gold, silver, copper, lead, and zinc polymetallic vein deposits at the Blackstone property.
The reduction of ZnO with a carbonaceous material using concentrated solar radiation as energy source is an innovative concept (1) for the storage of solar energy in Zn as a "solar fuel" prior to its use for the production of electricity in Zn-air fuel cells or of hydrogen by splitting water with Zn. In both cases ZnO is formed, which can be reprocessed to Zn in the solar plant, creating a cyclic process (2) for the production of metallic Zn as a commodity with drastically reduced CO2-emissions compared to conventional fossil-fuel based Zn-production. This paper gives an overview over the SOLZINC-project, in which we investigate the scientific and technological problems of scaling up this novel technology. Based on the small scale investigations a batch process (1 batch per day) using a concentrated beam down radiation heating the ZnO-C mixture has been selected for upscaling. The chosen furnace concept using concentrated solar irradiation to react ZnO and a solid carbon material to produce gaseous Zn has been further optimized on 5-10 kW scale. The necessary input data for upscaling have been generated. The results with respect to operation temperature requirements, overall reaction rates, choice of specific C-material for reduction and of construction materials of the furnace are used to design and build a pilot plant at a scale of several hundred kW. The use of Zn-dust as to be produced from the offgas of the solar reactor for mechanically rechargable Zinc-air fuel cells has been demonstrated.
The two-step carbothermic ZnO/Zn cycle is one of the most promising routes for producing hydrogen by splitting water with the aid of concentrated solar energy. In a first endothermic step concentrated solar energy is used as the source of process heat to produce Zn and CO from ZnO and a carbon source, e.g. charcoal. The solar produced Zn can be stored and eventually transported before being exothermically reacted with steam to produce H2 and ZnO. The produced CO may be exothermically shifted to H2 by reaction with water, or used for onsite power production. The solar step has been successfully tested within the EU’s R&D project SOLZINC on a pilot scale of 300 kW concentrated solar power, yielding up to 50 kg/h of 95%-purity Zn. The Zn in different physical forms can be used for hydrogen production. Several options have been investigated for this process on laboratory scale.
The hydrolysis of zinc powder was studied in an aerosol to determine if high conversions are feasible at short residence times and high dispersions. This reaction is the low temperature hydrogen formation step in a two step zinc/zinc oxide based thermo-chemical cycle for water splitting using solar energy. Zinc particles with an average size of 158 nm were reacted with water vapor to form hydrogen and zinc oxide in an aerosol ﬂow tube reactor at ambient pressure (82 kPa) between 653° and 813° K and a water concentration of 3%. The highest conversion observed in the ﬂow system was about 24% at 813° K and a gas residence time of ~0:6 s. Non-isothermal thermogravimetric analysis (TGA) indicated that complete conversion of zinc to zinc oxide could be achieved for longer residence times. An activation energy of 132 ± 27 kJ/mol was calculated from the TGA experiments using a model-free isoconversional method. Standard reaction models did not describe the data so an empirical order of reaction rate law was used instead. Reaction rates in the aerosol ﬂow reactor were higher than those calculated from the TGA measurements, likely due to lower mass and heat transfer resistances in the aerosol.
This article provides a comprehensive overview of the work to date on the two-step solar H2O and/or CO2 splitting thermochemical cycles with Zn/ZnO redox reactions to produce H2 and/or CO, i.e., synthesis gasâ€”the precursor to renewable liquid hydrocarbon fuels. The two-step cycle encompasses: (1) The endothermic dissociation of ZnO to Zn and O2 using concentrated solar energy as the source for high-temperature process heat; and (2) the non-solar exothermic oxidation of Zn with H2O/CO2 to generate H2/CO, respectively; the resulting ZnO is then recycled to the first step. An outline of the underlying science and the technological advances in solar reactor engineering is provided along with life cycle and economic analyses.
Thermodynamic studies were carried out for the hydrogen production via zinc hydrolysis. It is shows that it is reasonable to keep the temperature of zinc hydrolysis under 900 oC. The system pressure has no notable thermodynamic influences on the hydrolysis reaction. The initial H2O/Zn molar ratio should be controlled in a reasonable range.
Dissociation of fine zinc oxide particles was explored at ultra-high temperatures (1700-2000 K) using a graphite aerosol reactor heated in a graphite tube furnace. The dissociation of ZnO is a critical reaction in a two-step water splitting process for the production of hydrogen, and the reaction can be performed in solar thermal reactors for sustainable hydrogen generation. Fundamental understanding of the reaction is critical to solar reactor design, and so the dissociation must be explored at residence times typical to these reactors (0.05s to 1.5s). An experimental test apparatus was designed to study the kinetics of this reaction, and test points were run using this reactor. Conversions between 30% and 70% were obtained at temperatures ranging between 2000 K and 2300 K and residence times scattered about 1.2 s. With this apparatus, a complete experimental campaign can be performed to determine the kinetic rate law for the ZnO dissociation reaction.
Solar photochemical means of splitting water (artificial photosynthesis) to generate hydrogen is emerging as a viable process. The solar thermochemical route also promises to be an attractive means of achieving this objective. In this paper we present different types of thermochemical cycles that one can use for the purpose. These include the low-temperature multistep process as well as the high-temperature two-step process. It is noteworthy that the multistep process based on the Mn(II)/Mn(III) oxide system can be carried out at 700 Â°C or 750 Â°C. The two-step process has been achieved at 1,300 Â°C/900 Â°C by using yttrium-based rare earth manganites. It seems possible to render this high-temperature process as an isothermal process. Thermodynamics and kinetics of H2O splitting are largely controlled by the inherent redox properties of the materials. Interestingly, under the conditions of H2O splitting in the high-temperature process CO2 can also be decomposed to CO, providing a feasible method for generating the industrially important syngas (CO+H2). Although carbonate formation can be addressed as a hurdle during CO2 splitting, the problem can be avoided by a suitable choice of experimental conditions. The choice of the solar reactor holds the key for the commercialization of thermochemical fuel production.
Production of hydrogen via hydrolysis of zinc with steam is an essential step in the Zn/Z nO thermochemical cycle for splitting of water. Recent studies on reducing ZnO to Zn metal with the aid of concentrated solar energy stimulated the interest in the hydrolysis of the zinc for hydrogen production. One of these studies was focusing on solar carbothermal reduction of ZnO to produce zinc powder (EC/FP5-SOLZINC project). The current paper deals with the hydrolysis process of this material which will be referred to, hereafter, as SOLZINC. Test results obtained during the hydrolysis of SOLZINC powder in batch experiments at atmospheric pressure demonstrate possibilities of fast and high conversion of SOLZINC powder with steam to ZnO powder and hydrogen without intermediate melting or evaporation of zinc and indicate that the reaction occurs in two different rates, depending on the preheating temperature. A slow reaction starts at about 250 ◦C and the hydrogen output increases with reactor temperature. The fast stage starts as the reactor temperature approaches 400 ◦C. Above this temperature, the reaction develops vigorously due to fast increase of the reaction rate with temperature resulting in releasing additional exothermic heat by the reacted powder. Increasing the preheating temperature (when the steam ﬂow starts) from 200° to 550° C can improve the SOLZINC conversion during the fast stage from 24% to 81% and increase the hydrogen yield. When the fast stage decays, slow reaction can be continued on for a long time until the hydrogen production is fully achieved.
The EU research project SOLZINC accomplished a pioneer technology demonstration of a large-scale solar chemical plant. The key component is PSI's 300-kW solar chemical reactor for the production of zinc by carbothermic reduction of ZnO. Its testing at a large-scale solar concentrating facility in the 1300° - 1500° K range yielded up to 50 kg/h of 95%-purity Zn with energy conversion efficiency (ratio of the reaction enthalpy change to the solar power input) of about 30%. The SOLZINC process provides an efficient thermochemical route for the storage and transportation of solar energy.