Nah, you don't just want to equalise concentrations of glucose between urine and blood - you want to get as much sugar back into the blood as you possibly can. I suspect there is active transport involved and maybe some more complicated, sneaky processes going on. OP, I recommend you crack an A-Level biology textbook. It'll be in there.
- Study Helper
Firstly, the glucose in the proximal tubule is co-transported with sodium ions into the proximal convoluted tubule walls via the SGLT2 cotransporter. Some (typically smaller) amino acids are also transported in this way. Once in the tubule wall, the glucose and amino acids diffuse directly into the blood capillaries along a concentration gradient. This blood is flowing, so the gradient is maintained. Lastly, sodium/potassium ion active transport pumps remove sodium from the tubule wall and the sodium is put back into the blood. This maintains a sodium concentration gradient in the proximal tubule lining, so the first step continues to happen.