Question 1: (55 marks) Students are required to develop the instrumentation and control for the cement ball mill grinding unit and separator as described below and shown in figure 1. Ensure that all the requirements of the measuring instruments for the cement ball mill grinding unit, variable speed fan, dynamic separators, valves and signal transmission system are covered. Process Plant Description: The clinker formed from the pyro-cooler section are stored in a Silo. The Silo is a large storing device for handling bulk solids. In the cement ball mill grinding system, the input materials are clinker, gypsum, fly-ash (depending on the type of cement is to be produced) and additives. Assume that they are producing Pozzolana Portland Cement (PPC), in which fly-ash is used For ordinary Portland cement(OPC), fly-ash is not used. In the PPC type cement, the input materials Clinker, Gypsum, and fly-ash have a gravity feed into the weigh feeder. The values of these inputs are in Tons per Hour (TPH). The weigh feeder is a transporting device. These materials are then collected in a bin which has a controlling gate to adjust the level of the bin. The level of bin is to be maintained at around 15%. The controlling gate operates within 0 - 100% The materials from the bin are fed into the ball mill for grinding. The ball mill is filled with ball bearings for crushing the materials. The ball mill is in constant rotation and the materials are crushed inside. The fine materials output from the ball mill go to the bucket elevator which is located at the mill outlet. The ball mill material temperature at the outlet is controlled by a water pump system. Normal outlet material temperature is maintained at around 110C. There would be two water