Figure 5
From: Changes in pore structure of coal caused by coal-to-gas bioconversion
A conceptual mechanism for bioconversion of coal. (A) Pore structure before biogenic treatment. There are several isolated and accessible meso-/micropores surrounding the macropore surface where bacteria cannot go into. (B) Pore structure after biogenic treatment. Both isolated and accessible meso-/micropores vanished (Fig. 4A,B,C and D) and macropore surface becomes smoother (Table 3). (Note: The cyclic flow chat in the middle shows the process of coal-to-gas bioconversion: 1) Isolated meso-/micropres became accessible; 2) Bacteria continuously consumed the coal matrix near the surface of meso-/micropores; 3) Newly generated accessible meso-/micropres vanished; 4) Another bioconversion cycle began).
