Determine the cost ($/1000kg) of producing low-pressure (LP) steam (along with power production) using a natural gas fuel source. Assume that steam is produced at the highest pressure (HP) level, and consider the specific case wherein this HP steam is let down from the high-pressure header to a low pressure header (to produce LP steam) through a turbine, thereby generating electrical power in the process. Assume the following: a. Fixed capital investment associated with the initial purchase of the steam generation facilities has been accounted for elsewhere. Hence, account only for the operating costs associated with steam (and power) production. b. The source of fuel is assumed to be natural gas that costs $3.16/GJ (Table 8.3). c. Boiler efficiency =90%. d. Turbine efficiency =75%. e. The steam produced would still be in superheated state and would hence need to be desuperheated to convert it to a more usable saturated steam. f. Remember to take credit for the electricity produced; if all the individual costs (expenses) are conventionally designated with a positive sign, then the saving/income from the electricity produced may be designated with a negative sign when determining the net cost. Follow Example 8.6 in your textbook (Turton et al., 5th ed.) for details of the calculations involved in producing HP steam starting with bfw, followed by MP steam from HP steam. A similar approach may be applied for LP steam production. Show all intermittent steps involved in the calculations. Use Steam Tables and enthalpy charts to retrieve required data if needed. (NIST website is a good online source for material property data) Note: Design trivia The scenario here includes power production. An alternative to this is one without power production, in which case, a turbine would not be required; simply throttling the high pressure steam through a valve would suffice to produce low pressure steam. Such a design represents wasteful expenditure of energy due to throttling and is acceptable only when installing a turbine is not profitable or when a valve is necessary for control purposes