If you memorise with good technique it shouldn't take longer than a couple hours at worse. Don't read every line again and again til you can do the whole thing. Split your essays into paragraphs, and split those paragraphs into chunks of 3-4 points.
Read the first point three times, then try produce it without reading. If you can't, read it 3 more times, and try again. Do this until you can produce it from memory. Then do the second point, and do it so you can produce the first two points, then keep doing it until you've memorised that chunk. Once you complete a chunk of 3-4 points, start the same process again.
Eventually you can try recall the whole essays, and after 3-4 times you should be able to recall the whole thing.