SMR unit and food grade CO 2 tanks
fuel gas required by the steam reformer. In our case, to recover CO 2 , we use point 1 shown in Figure 1 . Experimental, theory and/or calculations The plant used to develop this study is a side-fire type SMR fed with natural gas. It consists of a reactor downstream of the main reformer – to eliminate CO from the syngas as much as possible (water-gas shift reaction, HTS) – a plant for capturing CO 2 using an absorption process with activated amines, and a liquefaction plant for CO 2 (for later sale). Previous literature mentioned that in addition to maintaining the production of H 2 , it was possible to substantially reduce the amount of CO 2 , CO and CH 4 vented to the atmosphere from the non-condensable gases of the CO 2 liquefaction unit, using them as feed to the reformer and thus decreasing the consumption of natural gas. Secondly, to increase the profits of the business unit and to continue reducing CO 2 emissions, an unused asset – a CO 2 production plant that burned natural gas to produce it – was used to capture CO 2 from the SMR flue gases vented to the atmosphere (see Figure 1, point 2). Thus, about 25 t/d of CO 2 is recovered and sold in the local
If the H 2 content is as high as 80%, care must be taken to mix this stream with, for example, natural gas so that the heat required by the SMR is not less than that supplied by the tail gas from the PSA market, reducing emissions to the atmosphere by the same amount. This technique is very favourable for the industry since the stream rich in CO 2 is a gaseous effluent sent directly to the atmosphere. However, the practical use of this technique has some drawbacks, which must be known in advance so as not to make costly mistakes due to problems of amine solution degradation or internal corrosion, mainly in pumps and heat exchangers. Therefore, it is crucial to choose the right amine for each process, with the correct concentration, pressure and operating temperature. You also have to be careful about how the SMR operates in terms of excess O 2 in the combustion gases. If it is above 2-3%, amine
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