How much co2 is produced from steam methane reforming?
The Carbon Footprint of Steam Methane Reforming Thus, per 1 million standard cubic feet (SCF) of hydrogen produced from methane, 250,000 SCF of CO2 will be produced. There are 19,253 SCF of carbon dioxide in one metric ton, so 1 million SCF of hydrogen will produce 13 metric tons of carbon dioxide.
How efficient is SMR?
Steam methane reforming (SMR) has high hydrogen yield efficiency (∼ 74%) and is estimated to produce hydrogen at a cost of around $1.8 kg− 1 (US DoE, 2015a). The methane found in natural gas reacts with steam to produce a syngas consisting of hydrogen and carbon monoxide (Eq. 1).
What is methane steam reforming?
Steam methane reforming (SMR) is a process in which methane from natural gas is heated, with steam, usually with a catalyst, to produce a mixture of carbon monoxide and hydrogen used in organic synthesis and as a fuel 1. In energy, SMR is the most widely used process for the generation of hydrogen 2.
How is SC ratio calculated?
The steam to carbon ratio is the ratio of moles of steam to moles of carbon in the reformer feed. It is obtained by dividing the molar flow rates of steam and feed.
What is the ideal composition of reforming gas?
Partial Oxidation With less than the stoichiometric amount of oxygen available, the reaction products contain primarily hydrogen and carbon monoxide (and nitrogen, if the reaction is carried out with air rather than pure oxygen), and a relatively small amount of carbon dioxide and other compounds.
Is steam methane reforming expensive?
Hydrogen Production and Current Technologies For instance, the hydrogen production cost from natural gas via steam reforming of methane varies from about 1.25 US$/kg for large systems to about 3.50 US$/kg for small systems with a natural gas price of 0.3 US$/kg.
How efficient is steam methane reforming?
The efficiency of the steam reforming process is about 65% to 75%, among the highest of current commercially available production methods. Natural gas is a convenient, easy to handle, hydrogen feedstock with a high hydrogen-to-carbon ratio.
What are the steps in the methane reforming process?
The Steam Methane Reforming process can be broken down into five distinct steps: 1. Water enters the furnace, producing steam at a very high temperature. 2. Steam reacts with natural gas, producing hydrogen and carbon monoxide. 3. In the water shift reactor, carbon monoxide and steam react to form carbon dioxide and more hydrogen gas.
What happens when methane is converted to steam?
The steam forming step, where methane reacts with water to produce carbon monoxide and hydrogen, is an endothermic process. Thus, the process is usually maintained at approximately 850°C to obtain desirable conversion. [4]
What is the ratio of steam to carbon in steam reforming?
In addition to computing the micro-kinetic model, experimental work for methane steam reforming was conducted. A steam to carbon ratio of 2:1 was fed to the packed bed reactor, where experimental conversion data were obtained.
Where does the CO 2 come from in a steam reformer?
In a typical modern SMR plant, about 60% of the total CO 2 produced is contained in the shifted gas (i.e., after a water gas shift (WGS) unit), with the remaining 40% of CO 2 being the product of NG fuel combustion that provides heat input to the steam reformer ( Collodi, 2010 ).
What is the catalyst used in steam methane reforming?
Steam reforming is the reaction of methane (and other higher hydrocarbons) with steam in the presence of a catalyst to form carbon oxides and hydrogen. Most industrial catalysts are based on using nickel as the catalytic component, although platinum group metals (pgms) are used for some specific duties.
What is syngas formula?
A mixture of CO and hydrogen is known as syngas (synthesis gas or water gas). It is used for manufacturing methanol. It is produced by the action of steam on hydrocarbons or coke at high temperature in the presence of a catalyst. CH4(g)+H2O(g)1270K NiSyngasCO(g)+3H2(g)
What is steam reforming of methane?
In steam-methane reforming, methane reacts with steam under 3–25 bar pressure (1 bar = 14.5 psi) in the presence of a catalyst to produce hydrogen, carbon monoxide, and a relatively small amount of carbon dioxide. Steam reforming is endothermic—that is, heat must be supplied to the process for the reaction to proceed.
What is steam methane reforming?
What is the flow rate of steam reforming methane?
17.2.2 Steam methane reforming with CCS SMR streams CO 2 flow rate (kmol/h) CO 2 partial pressure (bara) Shifted gas 1,000 3.40 PSA tail gas 1,000 0.60 Flue gas 1,850 0.20
How is steam used to convert methane to hydrogen?
Steam methane reforming is a widely-used process to convert methane into a mixture of hydrogen and carbon monoxide (syngas). Due to its maturity, high efficiency, and relatively low cost, steam reforming is considered a viable option for supporting a future hydrogen economy.
Which is more economical natural gas or steam reforming?
In addition to the maturity of the technology, natural gas reforming is also the most economical among all hydrogen production pathways. [3] Methane steam reforming is a well-established process as shown in Fig. 1.
What are the products of the steam reforming reaction?
Steam reforming is an exothermic reaction that is carried out by passing a preheated mixture comprising methane (sometimes substituted by natural gas having high methane content) and steam through catalyst filled tubes. The products of the process are a mixture of hydrogen, carbon monoxide, and carbon dioxide.