Methanol, production economics

Methanol production economics highly depend on the feedstock selection and feedstock prices. Methanol can be manufactured from any hydrocarbon source naphtha, oil, coal, wood, biomass, LPG, etc. The naphtha, fraction of crude oil... 

Both new catalysts and new processes need to be developed for a complete exploitation of the potential of CO2 use [41]. The key motivation to producing chemicals from CO2 is that CO2 can lead to totally new polymeric materials and also new routes to existing chemical intermediates and products could be more efficient and economical than current methods. As a case in point, the conventional method for methanol production is based on fossil feedstock and the production of dimethyl carbonate (DMC) involves the use of toxic phosgene or CO. A proposed alternative production process involves the use of CO2 as a raw material (Figure 7.1)... 

Dong, Y. Steinberg, M., Hynol—an economical process for methanol production from biomass and natural gas with reduced C02 emission. In 10th World Hydrogen Energy Conference, Block, D. L., Veziroglu, T. N. Eds., Beach, Florida, June 20-24,1994, pp. 495-504. 

The production of methanol from synthesis gas is a well-established process (23, 102), and there have been predictions that methanol itself could become the fuel of the future (103). Whether or not this prediction will prove correct is debatable4 meanwhile, Mobil suggests that coupling known methanol production technology with their new process provides an economically attractive alternative to both Fischer-Tropsch fuels and direct utilization of methanol (104). 

The above reaction can be carried out in the presence of a variety of catalysts including Ni, Cu/Zn, Cu/SiO, Pd/SiO, and Pd/ZnO. In the case of coal, it is first pulverized and cleaned, then fed to a gasifier bed where it is reacted with oxygen and steam to produce the syngas. A 2 1 mole ratio of hydrogen to carbon monoxide is fed to a fixed-catalyst bed reactor for methanol production. Also, the technology for making methanol from natural gas is already in place and in wide use. Ciurent natural gas feedstocks are so inexpensive that even with tax incentives renewable methanol has not been able to compete economically. 

Synthetic methanol is one of the major raw materials of the organic-chemical industry. Methanol has economic stability and a stejdy growth rale ow-ing lo ihe low costs of production and diversity of applications. Nearly all Ihe methanol producers also make formaldehyde, which is... 

Corneil, H.G., Heinzelmann, F.J. and Nicholson, W.S., "Production Economics for Hydrogen Ammonia and Methanol During the 1980-2000 Period," Exxon Research Engineering Company Report No. BNL-50663, Linden, New Jersey, April 1977. 

Production Economics For Hydrogen, Ammonia And Methanol During The 1980-2000 Period, Exxon Research and Engineering Company, Government Research Contract No. 368150-S April 1977, Appendix A by Chem Systems Inc.", Cost of Production Estimates For Hydrogen, Ammonia And Methanol, October 21, 1976, P. 127-166. 

Thus, although hydrogen is used in methanol production, it can be taken straight from the steam-hydrocarbon reformer and does not require further purification and treatment as in the case of pure hydrogen production or ammonia production. The economics of methanol production are significantly affected by the thermal integration of the reformer (or other gas generation unit) with the rest of the plant. 

However, the economics of partial oxidation are significantly affected by a requirement of about 0.9 tons of oxygen per ton of methanol product. 

In conclusion, it can be stated that there is a high probability that methanol production will increase worldwide by an order of magnitude, as the advantages of its ease of production from cheap fuel sources, its beneficial effect upon the environment and its versatility are economically realized in the next twenty years. 

Table 124 summarizes the economic data available on methanol production from various feedstocks and by various processes. 

Under favorable conditions, when the front end of an existing ammonia plant has capacity reserves, and the bottleneck is, for example, compression and synthesis, and probably also C02 removal, a revamp to incorporate parallel methanol production might be economically attractive. Options for a partial retrofit are described in [1216] [1496] an example for a co-production in a side stream with a separate methanol loop is given in Figure 117 [1217]. 

TABLE 9.13 Gasification Processes Used for Economic Analysis of Methanol Production"... 

We have made cost analysis for the solar methanol production for the system of Fig. 1. In this analysis, SCOT-solar farm (Solar Concentration Off-Tower central receiver beam-down configuration) is used for solar concentrating system(Fig.2). This solar concentrating system has an economical advantage, since the heavy chemical plant can be installed on the ground. Since the high temperature of 1000-1200°C is obtained by the SCOT-solar farm, chemical plant (or reactor) for solar-assisted coal gasification can be operated. Table 1 shows estimated investment cost... 

In all these projects, economics plays a leading role. It is always necessary to secure the feedstock at a very low price (typically natural gas at not more than about 0.75 per mscf), which is only available in remote locations (e.g., stranded natural gas) with low local demand. This can be translated into a cost of methanol production of about 80 per tonne, or perhaps a maximum of about 90 per tonne if allowances are made for shipping costs, etc. Considering that methanol has a fairly low heating value of only about... 

In a commercial methanol plant, it is economically desirable to maintain a constant methanol production rate as the catalyst ages. With conventional, fixed-bed reactors, the teed temperature is raised gradually with time to compensate for catalyst deactivation. The mathematical model of catalyst deactivation developed in the previous section was used to test the feasibility of this strategy for a single slurry methanol reactor operating with CO-Rich Gas. The reactor was assumed to be completely backmixed, which simplifies the mathematics of the analysis [ref. 7]. 

Kuczynski and Westerterp have proposed an elegant means of removing the reaction products from a system [10, 11]. In the area of methanol synthesis, where the conventional process is limited in conversion per pass to about 30%, they proposed to adsorb the product onto an amorphous silica-alumina powder that trickles through the solid catalyst packed bed. At the bottom of the bed, this soKd absorbent is collected and depressurized to yield the methanol product. Even though the process looked economically viable, it has, to the best of our knowledge, not seen any commercial application. 

Summarising what has been discussed in section 4, we present the global production of some alternatives in Table V. The scale of demand for gasoline calls for huge investment to replace gasoline by, e.g., methanol. Economic factors as well as the low efficiency of methanol production (Tkble IV) indicate that careful consideration is required before vigorously pursuing alternatives like these. 

Profit calculated from the optimal policy was 26.5 million per year indicating that various grade methanols made from the three biomass feedstocks can be competitive with those made from conventional sources. The calculation was based on the unit manufacturing cost determined from a 26,200 X 10 /day methanol plant capacity (plant capacity III in Table IV). The study, however, disclosed the fact that the biomass feedstock costs are the dominating factor in the economics of methanol production. It would therefore be interesting to note how the optimum profits vary with feedstock cost. 

In the above section, the importance of carbon monoxide and carbon dioxide conversion and the technically attainable approach to the equilibrium has been described. However, these two parameters alone do not decide upon the optima-tion for the production of methanol from a specific synthesis gas. The methanol yield from the synthesis gas is of quite decisive importance for economically producing methanol on a commercial scale. Its this yield on which depend the quantity of synthesis gas which must be produced horn coal, cleaned, conditioned and compressed and the quantity of CO2, CO and H2 which must be removed from the methanol synthesis as purge gas and thus is lost to methanol production by the direct route. 

In BPl production, the recycling of spent catalyst, acids, glycol, and methanol contributes economical and environmental advantages [35]. Importantly, the handling of solid materials with possible skin sensitizing properties and toxicity is avoided, thereby eliminating human and environmental exposure. 

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