Oxygen syngas production

In addition to SMR, other technologies are used for syngas production from natural gas that involve addition of oxygen or air. The catalytic partial oxidation (CPO) reaction is given in Reaction (3) and in autothermal reforming (ATR) this reaction is combined with Reactions (1) and (2). 

Dyer P N etal, 2000, Ion Transport Membrane Technology for Oxygen Separation and Syngas Production. Solid State Ionics, 134, 21-33. 

Steele B C H etal., 2000a, Ceramic ion conductors for fuel cells, oxygen separation and syngas production. Ceramics Getting into the 2000 s, Pt D, CIMTEC. 

FIGURE 6.32 Schematic diagram of an integrated distributor/extractor membrane reactor based on the combination of dense ceramic oxygen and hydrogen transport membrane for syngas production. 

Dyer, P.N. Richards, R.E. Russek, S.L. Taylor, D.M. Ion transport membrane technology for oxygen separation and syngas production. Solid State Ionics 2000, 134, 21-33. 

A large part of the cost of a syngas production plant based on partial oxidation is for the air separation unit. Continuous research efforts are going on for reducing the cost of this step. One possibility is to use oxygen-selective membranes integrated in a partial oxidation reactor, as illustrated in Fig. 13. Air is introduced... 

SrCoo 5FeOt showed a remarkable structural stability at high temperature and with different oxygen partial pressure. The conversion of methane using this tube was >98%, the selectivity to CO was 90%, and the H2/CO ratio was around 2.0. Some of these reactor tubes have been tested for syngas production up to 1000h. 

The disk type membrane reactor made of BaCoo.4Feo.4Zro.203 j in syngas production experiments at 850°C can be operated steadily for more than 2,200 h with a high catalytic performance of 96-98% CH4 conversion, 98-99% CO selectivity and an oxygen permeation rate of 5.4-5.S ml/cm. min. Moreover, a short induction period of 2 h was also obtained. 

Lao.sSrijGao.eFei.aOs+s [24] and SrFeCoo.sOx [65] were also successfully used as MIECM for POM more than 1,000 h. A membrane reactor based on a brown-millerite structure materials could be continuously operated for over one year under syngas atmosphere at 900°C [66]. The syngas production rate was 60ml/cm. min, and equivalent oxygen permeation flux was 10-12 ml/cm. min. The composition of the membrane was not specified in the literature. 

Our research is focused on the control of both the microstructure and the architecture of perovskite-type mixed-conducting reactors for high temperature applications, especially for oxygen separation from air and syngas production. 

Figure 10-14. Plasma (electric) energy cost of syngas production during plasma conversion of kerosene as function of specific energy input in the system (1) partial oxidation (2) steam-oxygen conversion with preheating of air (3) steam-oxygen conversion with excess water, (4) steam-conversion in low-temperature regime (5) steam conversion in high temperature regime.

These estimates give only an upper limit of oxygen permeation rate because surface exchange reactions may result in some suppression of the overall transport. For the conditions typical for syngas generation (pO2=0.21 atm, pOj = 10 atm, 950°C), the results for the membranes with L = 0.1cm and different chromium contents are shown in Fig. 3. In the calculations at high pressures the ion conductivity values were assumed to be nearly equal to those at low pressures. Fig. 2. It is seen that the permeation rate in chromium doped samples is smaller than in the parent ferrite. Nonetheless, it may achieve a value of about 4 ml cm min in the sample with y = 1, which corresponds to the syngas production rate of about 20-25 ml-cm -min in the methane partial oxidation process. In combination... 

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