Production capacity, methanol synthesis

Methanol production today is not a sustainable process but is part of a petrochemical route for conversion of fossil carbon into chemicals and fuels (see Section 5.3.3). It has to be emphasized that a one-to-one upscaling of existing industrial methanol synthesis capacities for fuel production is not useful. This is mainly because the current industrial process has not been developed and optimized under the boundary conditions of conversion of anthropogenic C02, but rather for synthesis gas feeds derived from fossil sources such as natural gas or coal. The switch to an efficient large-scale methanol synthesis with a neutral C02 footprint is still a major scientific and engineering challenge, and further research and catalyst and process optimization is urgently needed to realize the idea of a sustainable methanol economy. ... 

In 2009, worldwide production of methanol was around 40 million metric tons. Although this amount represents only 0.01% of the worldwide gasoline production, it is nearly equivalent to the total biodiesel and bioethanol production [11], From this number, it is clear that a large-scale replacement of gasoline by methanol as fuel would require an enormous increase of worldwide methanol synthesis capacities. Today, chemical intermediates dominate methanol consumption. Formaldehyde a platform molecule for the synthesis of polymer resins - is responsible for nearly half of the total demand. Acetic acid, MTBE, and methyl methacrylate - a monomer -constitute another 25% [7, 12]. Direct fuel and additive usage accounts for 15% of demand but is expected to rise. 

Methanol synthesis plants utilizing the low-pressure process currently operate at capacities of 2 x 105 to 2 x 106 metric tons per year [15]. Such installations are composed of a synthesis gas production unit, the actual methanol synthesis reactor, and a separation and purification section. The production and purification of synthesis gas accounts for 50%-80% of the total cost of methanol production, with the remaining cost associated with the actual synthesis and purification of methanol [2, 8], Although a variety of carbonaceous feedstocks can be transformed into synthesis gas, the steam reforming of natural gas (Equation [4]) is by far the most common option, especially for large plants [2, 15-16] ... 

One of your customers is a manufacturer of methanol. Her firm has several plants, with a huge production capacity. A methanol plant converts methane and water into methanol in two steps. In the first reformer reactor methane is converted into carbon monoxide and hydrogen (Figure 17-2). In the second synthesis reactor the carbon monoxide and part of... 

Then the product gas is fed to a low-temperature reactor where a Cu/Zn-Al2O3 particulate WGS catalyst works at about 200°C. Outlet CO concentration is decreased to <0.5%, while the remaining CO, which can poison downstream ammonia or methanol synthesis catalysts, is removed by pressure swing adsorption (PSA) unit. This method exploits the adsorption capacity of different molecular sieves or active carbon, which selectively permit the crossover of hydrogen but not of the other compounds present in the effluents. This technology has been... 

Methanol synthesis Syngas (essentially hydrogen, carbon monoxide, carbon dioxide) reacts catalytically to methanol at medium pressures and medium temperatures (200-300 °C). Typical plant capacities go up to 5000 t methanol/ day a hydrogen content in the syngas of 70 % and 2520 Nm /t of syngas consumed for ammonia production result in an hourly hydrogen consumption of 370,000 Nm. Methanol serves as chemical feedstock for the production of further chemicals. 

Fig. 15 gives a simplified flow sheet of the BASF plant [534, 1007]. The plant has a present capacity of 40,000 tons [1006]. Some years ago up to 70% of the starting methanol was replaced by dimethyl ether, which is obtained as a by-product in the methanol synthesis. Another plant with a capacity of 30,000 tons/year is operated by The Borden Chemical Co. in Geismar (U. S.A.) under license from BASF [1007, 1008]. 

T/year. Such a spectacular rise in reactor capacity is evidently tied to the growing market demand, but its realization undoubtedly also reflects progress in both technological and fundamental areas, pressed by the booming construction activity of the sixties and early seventies. Saturated markets and the construction of production units in newly industrialized countries have slowed down this capacity increase in the eighties. The present decade saw new spectacular developments. The utilization of remote natural gas and the associated transport problems has provided a new impetus to the development and construction of giant reactors for its conversion near the production sites methanol and ammonia synthesis reactors with a capacity of 1,600,000 T/year are now in use. 

Methanol is a versatile, readily available Ci-compound made from synthesis gas. Large scale industrial methanol production from CO/H2 was started up in 1925 by BASF using Zn0/Cr203 catalysts. The present methanol production capacity has been reported to be 21 mio t/a, while the actual demand is only in the range of 12 mio t/a. This overcapacity is mainly due to the build-up of new plants in the Midde East, Eastern Europe, New Zealand and Latin America, where surplus natural gas is available at a very low price [1,2]. The ready supply as well as the low raw material costs will keep the price of methanol low in the near future. This will stimulate methanol demand and will help to introduce new methanol-based processes for motor fuels as well as for organic base chemicals [3]. 

The conversion of natural gas to methanol via syngas is a widely used industrial process. A typical conventional process includes desulfurization of natural gas, steam reforming, methanol synthesis and purification by distillation. Steam reforming of natural is an endothermic reaction and operates at high temperatures (reformed gas effluent at about 800880°C). Methanol synthesis from syn is an exothermic reaction and operates at 200300°C. Heat integration and recovery is an important feature of the process. The trend in methanol production has been toward larger capacity and improved energy efficiency. 

For many years, the overwhelming feedstock of choice for methanol producers has been natural As of 1990, some 75% of the world s methanol production capacity was based on a natural feedstock. Steam reforming with its low sulfur feed (typically, feeds to a reformer contain less than 0.1 ppmv total sulfur) makes synthesis that is particularly well suited to feed a loop containing Cu-Zn catalyst. With the advent of the low-pressure process (pressures of 10 MPa, 100 atm, or less), it became advantageous to feed gases to a loop that were not necessarily stoichiometric because of the overall reduction in compression requirements. 

Althou MTBE is nerated as a by-product of propylene oxide production [125], direct synthesis by acid-catalyzed addition of methanol to isobutylene is necessary to meet the rapid increase in worldwide MTBE demand. Worldwide capacity of MTBE is expected to double by 1995 from the 1992 level of 377,000 bbl/day [125,126], and much of this increased capacity is expected to come from new plants and MTBE expansions [126]. 

The new rathenium catalyst has been used in the Pacific Ammonia Inc plant at Kitimat in British Columbia since 1992. Ammonia had been made there, from the methanol plant purge gas, since 1986 using a conventional iron synthesis catalyst. The new rathenium catalyst converter was in series with the old converter. Although in 1992 there was no additional synthesis gas to increase production capacity, the ruthenium catalyst operated well in a radial flow reactor and reduced both the steam and electricity used by 30-40% and 5-10% respectively. The new catalyst was said to be twenty times as active as the iron catalyst, and the effluent gas contained about 20% ammonia. 

Hydrogen cyanide is an important building block chemical for the synthesis of a variety of industrially important chemicals, such as 2 hydroxy-4 methylthiobutyric acid, adiponitrile, nitrilotriacetic acid, lactic acid, and methyl methacrylate. The primary commercial routes to hydrogen cyanide are the reaction of methane and ammonia under aerobic (Andrussow Process) or anaerobic conditions (Degussa Process), or the separation of hydrogen cyanide as a by-product of the ammoxidation of propylene < ) The ammoxidation of methanol could represent an attractive alternate route to HCN for a number of reasons. First, on a molar basis, the price of methanol has become close to that of methane as world methanol capacity has increased. However, an accurate long term pricing picture for these two raw... 

A few ammonia plants have been located where a hydrogen off-gas stream is available from a nearby methanol or ethylene operation (e.g., Canadian plants at Kitimat, BC and Joffre, Alberta). Gas consumption at such operations range from 25 million to 27 million BTU per tonne of ammonia, depending on specific circumstances. Perhaps more important, the capital cost of such a plant is only about 50% of the cost of a conventional plant of similar capacity because only the synthesis portion of the ammonia plant is required. However, by-product carbon dioxide is not produced and downstream urea production is therefore not possible56. 

The SGP crude synthesis gas is utilized to manufacture a wide range of end-products. Ammonia is the predominant product with over 50% of the SGP capacity being devoted to manufacturing this material. Methanol accounts for the second largest usage of SGP synthesis gas with oxo-products in third... 

Application To produce methanol from natural or associated gas feedstocks using advanced tubular reforming followed by boiling water reactor synthesis. This technology is an option for capacities up to approximately 3,000 mtpd methanol for cases where carbon dioxide (C02) is available. Topsoe also offers technology for larger-scale methanol facilities up to 10,000 mtpd per production train and technology to modify ammonia capacity into methanol production. 

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