Anhydrous ammonia prices rise to nearly $730/ton in July

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Anhydrous ammonia (NH3) prices to rise. The price increase is roughly commensurate with the uptick in natural gas prices to $3.6/1000ft3, a high not seen since 2018 (excluding the momentary jump in February caused by an aperiodic cold event in Texas), we can expect if oil reaches a sustained period of $100+, natural gas will follow its usual ratio with oil, sending anhydrous well above 800, likely in the 900 range. Pochari Technologies’ process intensified ammonia system will prove exceedingly more competitive in this future peak hydrocarbon environment. The beauty of this technology is instead of being dependent on an inherently volatile commodity (natural gas), which for the most part, is an exhaustible resource, hence a gradual increase in price over time, Pochari Technologies is only reliant on polysilicon as a commodity, which will continue to go down in price with increased production since silica is effectively inexhaustible, 46% of the earth’s crust! Note that according to the USDA statistic, there are effectively no sellers offering price below 700, so the standard deviation (SD) is very small. This means it’s unlikely for some farmers to be able to snatch up good deals if they are savvy buyers.

Reduced CAPEX alkaline electrolyzers using commercial-off the shelf component (COTS) design philosophy.

Posted on  by christophepochari

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Dramatically reducing the cost of alkaline water electrolyzers using high surface area mesh electrodes, commercial off the shelf components and non-Zirfon diaphragm separators.

Christophe Pochari, Pochari Technologies, Bodega Bay California

Alkaline electrolyzer technology is ripe for dramatic cost reduction. Current alkaline electrolyzer technology is excessively expensive beyond what material costs would predict, mainly due to very small production volumes, a noncompetitive market with a small number of big players, and relatively little use of COTS (commercial off the shelf) methodology of cost reduction. Pochari Technologies’s researchers have thus applied this methodology to finally bring to market affordable hydrogen generators fabricated from readily available high-quality components, raw materials, and equipment procured on Alibaba.com ready to be assembled as kits to reduce labor costs. An alkaline cell is a relatively simple system, consisting of four major components: The electrode (a woven wire mesh), a gasket (made of cheap synthetic rubbers, EPDM etc), and a material for fabricating the diaphragm membrane for separating and oxygen and hydrogen while permitting sufficient ionic conductivity (usually composites of potassium titanate (K2TiO3) fibers and polytetrafluoroethylene (PTFE) (as felt and as woven), polyphenylene sulfide coated with zirconium oxide, (Zirfon), or polysulfone, and asbestos coated with polysulfone. Many polymers are suitable for constructing separators, such as Teflon® and polypropylene”. “A commercially available polyethersulfone ultrafiltration membrane (marketed as Pall Corporation, Supor®-200) with a pore size of 0.2 um and a thickness of 140 um was employed as the separator between the electrodes”. Nylon monofilament mesh with a size of over 600 mesh/inch, or a pore size of 5 micron can also be used. Polyethersulfone is ideal due to small more size, retaining high H2/O2 selectivity at elevated pressures. It can handle temperatures up to 130 C. If polyethersulfone is not satisfactory (excessive degredation rate if temperature is above 50 C), Zirfon-clones are available to purchase on B2B marketplaces https://b2b.baidu.com for $30/m2 from Shenzhen Maibri Technology Co., Ltd.

The fourth component are the “end plates” which consist of heavy-duty metallic or composite flat sheets which house a series of rods tightly pressing the stacks to maintaining sufficient pressure within the stack sandwich. For higher pressure systems, such as up to 30 bar, the endplates encounter significant force. Unlike PEM technology, noble mineral intensity in alkaline technology is relatively small, if nickel is to be considered a “noble” metal, than alkaline technology is intermediate. Nickel is not abundnant but not rare either, it’s approximately the 23rd most abundant element. For an alkaline electrolyzer using a high surface area electrode, a nickel mesh electrode loading of under 500 grams/m2 of active electrode surface area is needed to achieve anode life of 5 or more years assuming a corrosion rate of below 0.25 MPY. With current densities of 500 miliamp/cm2 at 1.7-2 volts being achievable at 25-30% KOH concentration, power densities of nearly 10 kW/m2 are realizable. This means a one megawatt electrolyzer at an efficiency of 75% (45 kWh/kg-H2 LHV) would use 118 square meters of active electrode surface area. Assuming a surface/density ratio of a standard 80×80 mesh, 400 grams of nickel is used per square meter of total exposed area of the mesh wires. Thus, a total of 2.25 kg of nickel is needed to produce 1 kg of hydrogen per hour. For a 1 megawatt cell, the nickel would cost only $1000 assuming $20/kg. This number is simply doubled if the TBO of the cell is desired to increase to 10 years, or if the power density of the cell is halved. Pochari Technologies is planning on using carbon-steel electrodes to replace nickel in the future to further redux CAPEX below $30/kW, our long term goal is $15/kW, compared to $500 for today’s legacy system from Western manufacturers. Carbon steel exhibited a corrosion rate of 0.66 MPY, while this is significantly above nickel, the cost of iron is $200 per ton (carbon steel is $700/ton), while nickel is $18,000, so despite a corrosion rate of at least 3x higher, the cost is 25x lower, yielding of 8.5x lower for carbon steel. The disadvantage of carbon steel despite the lower capex is decreased MTBO (mean time before overhaul). Pochari Technologies has designed the cell to be easier to dissemble to replace the corroded electrodes, we are also actively studying low-corrosion ionic liquids to replace potassium hydroxide. We are actively testing an 65Mn (0.65% C) carbon steel electrode under 20% KOH at up to 50 C and experiencing low corrosion rates confirming previous studies. We will continue to test these electrodes for 8000 hours to ascertain an exact mass loss estimate in mils per year.

For a lower corrosion rate of 1 um/yr, a total mass loss of 7% per year will occur with a surface/mass ratio of 140 grams/m2-exposed area, the nickel requirement is only $350 or 17.5 kg for one megawatt! Although this number is achievable, higher corrosion rates will likely be encountered. To insure sufficient electrode reserve, a nickel loading of around 400-500 grams/m2 is chosen. Pure nickel experiences an excessively high corrosion rate when it it “active”, it becomes “passive” when a sufficient concentration of iron (NiFe2O4), or silicate is found in the oxide layer. For Incoloy alloy 800 with 30% Ni, 20% Cr and 50% Fe experiences a corrosion rate of 1 um/yr at 120 C in 38% KOH, pure nickel is over 200 um. “The “active” corrosion of nickel corresponds to the intrinsic behavior of this metal in oxygenated caustic solutions; the oxide layer is predominantly constituted of NiO at 180°C and of Ni(OH) 2 at 120°C. The nickel corrosion is inhibited when the oxide layer contains a sufficient amount of iron or silicon is present”. The results drawn from this study indicates the ideal alloy contains around 34% Ni, 21% Cr, and 45% Fe. The cost breakdown for the three elements are $18/kg, $9/kg and $0.2/kg, giving an average of $8.1/kg. For a passive corrosion rate of 1 um/yr, a 10% annual material loss corresponds to a electrode mesh loading of 90-100 grams/m2, or $0.11/kW. That is 11 cents per kW! This does not include mesh weaving costs. A 600 mesh weaving machine costs $13,000. The conclusion is meshing costs are very minimal, less than a few cents per square meter.

For the diaphragm separators using a 200 um thick sheet of polyethersulfone (PES), around 20 grams is used per kilowatt, at a typical cost of PES of $25/kg assuming density of 1.37 g/cm2, the cost would be around $0.50/kilowatt assuming an electrode power density of 6.8 kW/m2 (400 miliamps at 1.7 volts). Since Pochari Technologies’ always adheres to COTS methodology, the expensive and specialized Zirfon membrane is dispensed with in favor of a more ubiquitous material, this saves considerable cost and eases manufacturability as the need to purchase a specialized hard to access material is eliminated. Gasket costs are virtually negligible, with only 4.8 grams of rubber needed per kilowatt, EPDM rubber price are typically in the range of $2-4/kg. For 30% NaOH at 117 C, a corrosion rate of 0.0063 millimeter per year (0.248 MPY) is observed for an optimal nickel concentration of 80%. This means 55 grams of Ni is lost for one square meter, if we choose 10% per year as an acceptable weight loss, we return to 550 grams per square meter as the most realistic target nickel loading, with much lower loading achievable with reduced corrosion rates. A lower concentration of KOH/NaOH and lower operating temperature can be utilized as a trade-off between corrosion and power density. The total selling price of these units cost including labor and installation is $30/kW. In 2006, GE estimated alkaline electrolyzers could be produced for $100/kW, clearly, must lower prices are possible today. At an efficiency of 6.5 MMW (47.5 kWh/kg-H2), the price is $1430/kg-hour. After the cell stack costs, which we demonstrated can be made very minimal with COTS design philosophy, the second major cost contributor is the power supply. For a DC 12 volt power supply, $50 is a typical price of 1000 watt DC power module. This, in compendium, alkaline stack costs are effectively miniscule, and the cost structure is dominated by the power supplies and unique requirements of low voltage direct current high amperage power. High efficiency DC power supplies cost as little as $30/kW and last over 100,000 hours.

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180 C at 38% wt KOH at 4 MPa Oxygen

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150 C at 38% wt KOH at 4 MPa Oxygen

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120 C at 38% wt KOH at 4 MPa Oxygen

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Typical alkaline electrolyzer degradation rate. The degradation rate varies from as little as 0.25% per year to nearly 3%. This number is almost directly a function of the electrocatalyst deactivation due to corrosion.

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Diaphragm membrane rated for up to 100 C in 70% KOH for $124/m2: $8.8/kW

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*Note: Sandvik materials has published data on corrosion rates of various alloys under aeriated sodium hydroxide solutions (the exact conditions found in water electrolyzers), and found that carbon steel with up to 30% sodium hydroxide provided temperatures are kept below 80 Celsius.

Cheap ammonia crackers for automotive, heavy duty mobility, and energy storage using using nickel catalysts

Industrial scale catalysts have been processed intensified by reducing particle size, increasing Ni loading, and increasing specific surface. “Employing the catalyst in powder form instead of in granulated or pellet form significantly reduces the temperature at which an efficient decomposition of ammonia into hydrogen and nitrogen can be effected”. The main reason why the industrial-scale annealing (forming gas) crackers have higher decomposition temperature is due to large catalyst pellet size, usually 20 mm. While typical industrial ammonia cracking catalysts from China (Liaoning Haitai Technology), have Ni loadings of 14%, with GHSVs of 1-3000 with conversion of 99+% at 800-1000 C, some literature pulled up from mining Google patents citing physical testing indicate variants of standard nickel catalysts with higher Ni loading with similar densities (1.1-1.2 kg/liter) can achieve GHSVs of 5000 at lower temperatures (<650 C) and retain high conversion (99.95%). Such a system would equate to a techno-economic power density of 3.85 kg cat/kg-H2/hr, yielding a net of 0.96 kg nickel/kg-H2 at a nickel price of $20/kg, equating to $20kg-hr capacity, leaving little incentive to use noble or exotic alloys. The rest of the cost is found in the metal components, of which around 7 kg of stainless steel is needed for a 1 kg reformer, costing about $140. Aluminum oxide support is virtually insignificant, costing only $1/kg. Pochari Technologies’ goal is to make ammonia crackers cheaper than standard automotive catalyst converters, this appears a tenable goal as catalyst converters require palladium and platinum, albite in smaller quantities. The reformer is approximately the size as a large muffler, which will be fitted near exhaust manifold of the engine, to minimize conductive heat losses through the exhaust. Beyond economics, the power density is already more than satisfactory, with the volume of the catalyst occupying less than 3.2 liters for a reformer capacity of 1 kg-H2-hr, most of the volume is occupied by insulation, the combustion zone (the inner-third portion of the cylinder), and miscellaneous piping, flow regulators, etc.

While the theoretical energy consumption is 3.75 kWh/kg-H2, the minimum energy consumption is somewhere in the order of 4.2-4.8 kWh/kg, but in reality, it is usually higher. This number can be easily ascertained by taking the specific heat capacity of the catalyst mass (mostly aluminum oxide), the active component (nickel 500 kJ-kg/K), the metallic components (500 kJ/kg-K for SS304) that comprise the reactor vessel, catalyst tubes, containment cylinder etc, and finally, the temperature required to raise 5.5 kg of gaseous anhydrous ammonia (2175 kJ/kg-K) to 800 degrees Celsius, which is exactly 2.65 kWh, plus any heat loss. We also need to take into account the higher capacity of the released hydrogen. As the ammonia progressively breaks down, hydrogen is released, this hydrogen has a certain residence time since for complete decomposition, the reformate gas will reside until no appreciable quantities ammonia is present, this in effect means the reformer is also heating hydrogen gas, not just ammonia, so we need add the heat absorption of the hydrogen, which is another 3.17 kWh (14,300 kJ/kg-K). This takes the total to 7.84 kWh/kg-NH3, very close to numbers found on industrial reformers. Heat loss through conduction is minimal, using 40mms of rock-wool insulation wrapped around a 100mm reactor vessel, we can reduce heat transfer for a 3 liter reformer to around 60 watts. The net total amounts to 7.9 kWh/kg NH3, or 23% of the LHV of hydrogen. Nearly 100% of this energy can be supplied by exhaust gases for H2-ICE systems, while for fuel cells, no such heat is available.

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Ultra-high efficiency non-alkaline hydrogen production technology.

Pochari Technologies has been searching for improved electrolytes for improved water electrolysis. During this investigation, this research effort naturally stumbled upon ionic liquids. Ionic liquids possess extraordinary properties especially in regard to their potential to perform catalysis, permit regeneration, while maintaining miscibility in water. Ionic liquids possess high electrochemical stability windows, up to 4.9 volts and 4.0 volts for the selected ionic liquids in our research. Imidazolium based ionic liquids have been previously investigated as electrolytes and demonstrated stellar results, particular in elevated Faradaic efficiency thanks to lower activation barriers in the HER. These selected ionic liquids are not alkaline no strongly acidic (mildly acidic), thus their corrosivity against metals is far less severe. Many ionic liquids are not miscible (soluble) is water, thus cannot be used as electrolytes for water electrolysis, certain ionic liquids that are miscible in water possess sufficiently high electrical conductivity to enable reasonable current densities, for example, one of the most common ionic liquids studied: 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM-PF4) pH of 5 and fully soluble it water, has an electrical conductivity of 3.7 millisiemens at room temperature for 100% concentration, for 12% in H2O, it increases to 29 millisiemens/cm, equivalent to 6% wt KOH in water. Another water soluble ionic liquid is 1-Ethyl-3-methylimidazolium tetrafluoroborate (EMIM-PF4), with 14.1 millisiemens as a pure solution, and around 85 millisiemens as an aqueous solution of 50% wt. In 2005, Roberto F de Souza first discovered the possibility of using ionic liquids as an alternative electrolytes to replace potassium and sodium hydroxide. Although ionic liquids for water electrolysis electrolytes has reserve scant research attention, and effectively zero commercial interest, its untapped potential is truly enormous. Ionic liquids also possess the advantage of relatively little to no toxicity, enabling safe handling and environmental disposal.

The rational for using the imidazolium based ionic liquid electrolytes instead of the alkaline solutions are two fold.

#1 Near 100% Faradaic efficiency enabled by reduced activation barrier.

In the few studies of imidazolium based ionic liquid electrolytes for hydrogen the evolution reaction (HER), each test using various electrodes demonstrated a minimum of 90% efficiency, with results as high as 98%, compared to a maximum of 75% for conventional alkaline mediums. This higher efficiency does come at the price of current density using the 1-butyl-3-methylimidazolium tetrafluoroborate due to its lower electrical conductivity. Using 1-Ethyl-3-methylimidazolium tetrafluoroborate, we estimate current density of 140 milliamp/cm2 or more. Lower current density is less of a limitation for non-alkaline electrolysis since the electrolyte is less corrosive, enabling the use of less expensive materials, such as carbon steel. De Souza synthesizes a novel and obscure ionic liquid, 3-(triethylamine-N-yl)-propane-1-sultonate, with the same tetrafluoroborate anion and achieved current densities of 1.77 amps/cm2 permitted by its higher dissolved conductivity of 132 ms/cm. While this particular ionic liquid is not commercially available, it can be synthesized relatively easily. Pochari Technologies is currently studying 1-Ethyl-3-methylimidazolium tetrafluoroborate as the ideal electrolyte with potential current densities of 140 milliamp/cm2 with efficiencies over 90%. The advantage of this ionic liquid is commercial availability.

#2 Reduced corrosive stress:

Traditional alkaline electrolysis places significant corrosive stress on on the expensive electrode material. A typical alkaline electrolyzer’s cost structure is dominated by the electrode module, usually nickel anodes and cathodes, contributing up to 40% of the stack cost. Since KOH and NaOH strongly corrode metals, even highly corrosion resistance metals such as nickel, significant annual loss incourred, for large electrolyzers, many kgs of material are lost annually, requiring periodic overhaul depending on electrode thickness. Ionic liquids have been considered as corrosion inhibitors and have found not to be highly corrosive. “Previous studies on carbon steel pointed out limited corrosiveness of 1-butyl-3-methylimidazolium and 1-ethyl-3-methylimidazolium tetrafluoroborate, also in co-presence of amines and CO2; some imidazolium-based ILs are even considered for applications as corrosion inhibitors, due to their adsorption and consequent formation of a protective film on the steel surface”

List of available ionic liquids:

Cations:
1-Ethyl-3-methylimidazolium
1-Ethyl-2,3-dimethylimidazolium
1-Propyl-2,3-dimethylimidazolium
1-Butyl-3-methylimidazolium
1-Hexyl-3-methylimidazolium
1-Octyl-3-methylimidazolium
Trimethylbutylammonium
N-Ethylpyridinium
4-Methyl-N-butylpyridinium
Trihexyl(dodecyl)phosphonium

Anion:

Bis(trifluoromethylsulfonyl)imide
Tetrafluoroborate
Hexafluorophosphate
Ethylsulfate
Trifluoromethanesulfonate
Trifluoroacetate
Octylsulfate
Thiocyanate

Commercial availability:

1-Butyl-3 methylimidazolium tetrafluoroborate is available on commercial marketplaces for $60/kg. The anion (tetrafluoroborate) of these ionic liquids are known to very slowly decompose in aqueous solutions, so occasional addition of fresh ionic liquid is required, this is projected to add negligible operational cost.

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Process intensified miniature ammonia plant using advanced catalyst technology

Christophe Pochari, Pochari Technologies

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Distributed ammonia production, high-technological readiness fertilizer electrification for high irradiance photovoltaic geographies

The ammonia industry is in need of disruption. Highly consolidated industries such as chemical production are notably resistant to change and unwilling to alter their business models. Consumers often suffer as players will price-gouge the buyers with little bargaining power. Ammonia is a prime example, there is no substitute for anhydrous, thus farmers are at the mercy of large producers generating high returns. Large producers have monopolized the market and charge far above what the price of natural gas would predict. For example, as of April 2021, the price of anhydrous is $710/ton, while the price of natural gas is only $2.5/thousand-cubic feet, or $0.13/kg. The price of producing hydrogen from natural gas is only $1-1.5/kg, so the price of ammonia should only be $213/ton, with a reasonable estimate for plant CAPEX of $1500/TPY amortized over 15 years yielding less than $100/ton. The conclusion is ammonia shouldn’t be over $300 ton at today’s rock-bottom natural gas prices, yet ammonia prices continue to rise. Secondly, carbon-emissions are a concern but of which cannot be a nuisance to already cost-sensitive farmers, so the only way to reduce carbon emissions from ammonia is by producing it for a lower price than the current large-scale production methods. Thankfully, rapidly falling solar and electrolyzer costs have largely solved this problem for us. With production from water and air, distributed production becomes feasible, over-turning the current business model away from centralized production.

Modern photovoltaic systems wholesaling on Chinese marketplaces such as Alibaba sell for as little as $0.18/watt from RISEN ENERGY CO., LTD for monocrystalline architecture.
Degradation rates are typically around 15% for 20 years, or around 0.8% per anum. That means a 1 kW system will produce 84% of its original power output after two decades.
Panel type: 275-280/330-335W Multi-Module
Price per watt (USD): 0.28 High, 0.175 Low, 0.185 Average.
The average price for 350-watt panels is 18.5 cents per watt.
The second major cost input is the DC/AC converter. Using data from Alibaba, numerous products were sampled. The most cost-competitive DC/AC rectifiers were ones used for solar-powered well water pumps. 7.5 kW units were priced around $250, yielding a price per kilowatt of $34. In our case, we only need a DC-DC converter, stepping down the voltage from the panel peak of around 35 to 12 for the electrolyzer. DC/DC converters are roughly the same price as DC/AC inverters.

The Levelized Cost of Energy (LCOE) is determined by the irradiance available much more so than it is by slight differences in the panel module costs. A solar array in Scotland (880 kWh/kWp/yr) won’t be nearly as cheap as one in Chile (2300 kWh/kWp/yr), or in Los Vegas (1900 kWh/kWp/yr).

With the availability of low-cost photovoltaic energy without the need for balancing grid requirements, the need for storage is eliminated, this opens up the possibility of producing ultra-low cost hydrogen below the price of methane reforming. Hydrogen on its own is virtually useless, it has virtually no application as a fuel, thus we are forced to turn to ammonia. Until ammonia begins its use as a low-emission fuel in the near future, the fertilizer market is the biggest opportunity for disruption. Rather than purchasing overpriced ammonia for major producers who charge high margins, farmers can produce it themselves at cost, savings considerable sums of money and paying for the capital expenditure of the plant in a short time.

Contrary to popular belief among experts on catalytic synthesis, ammonia synthesis is actually very easy to scale down to levels permitting distributed production. In 1909, Haber originally produced 90 grams per hour using an osmium catalyst with a miniature plant. Using photovoltaic energy, farmers in regions with high annual irradiance can cover all of their fertilizer needs as well as covering their farm equipment propulsion using low emission ammonia fuel. Using autonomous production, payback times can reach less than 3 years depending on annual irradiance. Small scale ammonia plants suffer from lower efficiency due only to high heat transfer since the reactor vessel has a high surface to volume ratio. Using rock-wool insulation designed for high temperatures, with a thermal conductivity of 0.04 W/m-K, heat loss can be minimized and brought down to industrial-scale levels. For a 10 kg/hr reactor, 7 kWh of heat is released, the heat flux for a reactor this size would approximate 2 watts with 7” of rock-wool insulation. Over 90% of the compression energy needed can thus be met by the excess heat produced during the formation of the ammonia molecule.

For an ammonia reactor vessel of 3 meters in diameter, 100mm of insulation was used. This translates into a negligible heat flux of 0.22 kwh/m3 reactor volume heat flux for the typical large-scale plant. For a 1 kg/ht NH3 plant, the heat flux is 1.1 kwh/m3 with 14” of rock-wool insulation at 0.04 Wm-K.

An ammonia plant is in reality a quite simple device, ammonia reactors were once a technically challenging endeavor as high-temperature nickel alloys were not yet available. The reactor consists of a vessel that encompasses the catalyst tubes, within these tubes is a pebble-sized granular Iron catalyst. A small mesh is placed at the ends of the catalyst tubes to prevent unwanted migration of the catalyst pellets. The catalyst is relatively inexpensive and lasts 5-10 years. The particular catalyst used is the HTA110-1-H Pre-reduced ammonia synthesis catalyst by Liaoning Haitai Sci-Tech Development Co., Ltd. The composition of the catalyst is the standard for modern NH3 synthesis, consisting of alpha-Fe, supported on Al2O3, with CaO and K2O promoters. The particular catalyst is rated for up to 32 MPa pressures and 530 C operating temperatures. These ammonia synthesis catalysts are highly productive, with 1 kg of catalyst producing 0.37 kg of NH3 per hour. Thus, at current prices ($15/kg for bulk-purchases), the catalyst cost of a 80 TPY plant is only $1250!

One of the biggest challenges in producing a viable small-scale ammonia plant is purifying the oxygen. A maximum oxygen concentration of 40 ppm is allowed to minimize temporary catalyst poisoning, a concentration of 99.999% is ideal. Using carbon molecular sieves, a yield of 90 Nm3-N2/ton can be achieved. For 3 Nm3/hr, 60 kg of molecular sieve is needed assuming an output density of 50 Nm3-N2/ton. The final concentration of oxygen would be 10 parts per million. The price of the carbon molecular sieve is $8-10/kg.

The second challenge is syngas compression. On large plants, centrifugal compressors dominate. At high flow rates, boundary layer and tips losses are minimal, but when these compressors are scaled-down, these losses increase making reciprocating compressors more attractive. Pochari Technologies uses a novel low-speed hydraulic compressor using ultra-low friction technology. Since the plant is relatively small, the footprint of the compressor is not a large concern, therefore we have oversized the compressor to enable it to operate at a lower speed, enabling low friction. While the compressor is oil-lubricated, a large absorbent module is utilized to capture the bulk of the unwanted oil residues that escape the piston ring.

Financial viability, specifications and rough cost breakdown for 77 TPY NH3 plant:

Solar array: 300 kWp $0.18/watt monocrystalline photovoltaic panels at 2030 kWh/kWp (Lancaster, CA): $54,000

DC-DC step up converter: $50/kw: $3,500

Douglas fir solar frame structure: $6000 (pre-Covid lumber prices)

Osmosis water distillation: 2 kWh/m3 15 LPH $100 ($1,500 for 500 LPH)

70 kW 8 MMW 38 kwh/kg 2 m2/kw $125/kw 15,200 kg/yr Dry cell HHO generator with pure nickel foil electrodes: $16,800

Sized for 75% kWp capacity at peak, can increase power density by 25% during peak hours, equaling 168 kW, oversized by 140% to eliminate the need for battery storage. 

Compression energy: 4 kWh heat energy per kg of hydrogen, insufficient to cover 3.5 kWh/kg compression

300 kg carbon-molecular sieve: $2,700

88 kg Fe2O3/K2O/CaO catalyst-hr 2700 kg/m3. $1250

Low-speed 350 bar 70 Nm3/hr oil-lubricated reciprocating compressor (12,000 hr MTBO): $7,000

Reactor materials, Inconel tubing, insulation, valves, fittings, flowmeters, and miscellaneous items: $5,000

Reactor volume: 37L

Total: $95,950

Pay-off time: 2.49 years

Total gross revenue @$500/ton: $38,500

Net revenue: $35,500

1st year return on capital (ROI): 36.99%

Annual maintenance cost, primarily compressor maintenance, principally compressor piston ring replacement: $3000

Techno-economic feasibility of micro-channel Fischer-Tropsch production using carbon-neutral hydrogen from municipal solid waste plasma gasification for producing liquid hydrocarbons

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Combining photovoltaic power with municipal sold waste plasma gasification, carbon monoxide can be produced along with hydrogen at nearly the same molar ration as required to produce long-chain liquid transportation fuels. Any fuel produced from a sustainable source such as solid waste diverts carbon away from new extraction, mitigating emissions. If 1 ton of fuel is burned that is produced from solid waste, 1 ton less fuel is extracted. Using micro-channel technology rather than classic tubular reactors, the size of the F-T reactor is reduced by an order of magnitude, reducing CAPEX and material usage. Low-cost non-noble cobalt catalysts provide high activity and long life. Graphite electrodes using 10 kV AC plasma torches provides high temperature 2000-3000C gasification temperature generating 513 and 400 Nm3 of CO and H2 respectively using 1.6 MW. 1.2 tons of solid waste can generate 0.27 tons of sulfur-free diesel fuel per day.

Sustainable diesel fuel market price: $946/ton ($3/gal)

Hydrogen source: Photovoltaic 40 kWh/kg-H2 140 kg-H2/t-diesel

Carbon source: Municipal solid waste plasma gasification: 243 kg/t-MSW @1,600 kWh plasma/t-MSW = 6.5/kWh/kg, 5600 kWh/t-diesel p. Hydrogen production: 32 kg/t-MSW

Solar plant CAPEX @0.20/watt: $60,000

DC/AC invertor: $15,000

Treated wood panel support structure: $8000

Plasma gasifier CAPEX: $10,000

Microchannel Fischer-Tropsch reactor: $8,000

Purification: $5,000

Total CAPEX: $106,000

Annual maintenance: $15,000

Revenue per ton MSW: $178

Power consumption: 6000 kWh/ton

MSW consumption: 1.2 tons per day,

Potential Revenue: $94,600

Return on capital: 75%