In this low magnification image the details of the liver's cellular structure aren't easily seen, but the general outline of the lobules can be made out without difficulty. This example is from a pig. Remember that the lobule is a three dimensional structure, and it projects down into the plane of section, and up out of it, too. Each lobule has a central vein , the site of drainage of blood.
Blood flows in from the periphery and leaves via the central vein.
Central veins from adjacent lobules coalesce to form larger vessels, and eventually all of the drainage leaves the liver via the hepatic vein. Here's an example of non-pig liver. The lobulation pattern is much less distinct the lobulation pattern is compared to that of the pig. Actually, at moderate magnifications you can pretty easily make out the boundaries of the lobules by observing the direction of radiation of the plates of hepatocytes, but the minuscule amount of CT makes it hard to see the lobulation in a low-power image like this one.