BE stands for Book Entry. What this means is that when a stock is purchased in the BE category, one has to take delivery of the stock(it must be entered in the books) to be able to sell it. Intraday trading as well as BTST trading isn’t allowed in stocks that fall in the BE category.
BL stands for Block Deals. Orders placed in the BL category should have a minimum purchase quantity of 5,00,000 shares. A separate window is provided by the exchange for the Block Deal session which is available for 35 minutes from when the market opens, i.e. 9.15am to 9.50am.