(Solved): A hydrocracker breaks down waxy products using hydrogen in the presence of a catalyst at high press ...

A hydrocracker breaks down waxy products using hydrogen in the presence of a catalyst at high pressure. After hydrocracking, hydrogen and light gases are separated from the liquid product in two stages - high and low pressure separators. Figure 2 shows this process. The

separator produces gases and liquid products leave at the base. The control valve is used to reduce the pressure and to ensure that the gases produced in the HP separator do not pass through the line to the LP separator. The valve PCV1 keeps the LP separator at 6 bar.g. The liquid product contains residual waxes. a. There is a larger copy of Figure 2 on page 9 (it is labelled Figure 4). Remove page 9 from this booklet. Draw on it the ancillary equipment, instrumentation, additional valves, and control lines necessary to control the process. Do not conduct a HAZOP. Use the conventional symbols where possible and include a legend for any other symbols that you use. Indicate the signalling method and whether valves fail open/closed. All control valves in the system must be regularly removed for maintenance (they are all maintained at once). Provide an isolation system based on valves, indicating the type of valve used. Briefly justify your design choices, including the SIL of any safety instrumented system. [15 Marks] b. List, and briefly explain, the other layers of protection that the site should put in place. [3 Marks] c. Suggest two ways of improving the inherent safety of the process. [3 Marks]