Inside process battery limit

It is common that decisions for implementing beneficial improvement ideas are made with the evaluation based on the inside process battery limit (ISBL). It is not surprising to find, in some eases, that the implemented energy-saving projects deliver far less benefits and require mueh high capital compared to what are predicted from evaluation. The reason is that energy savings at the process level can only be realized at the site-wide balanees when the utility bills come at the end of the year. 

The process flowsheet inside the battery limits (IBL) is at this stage unknown. However, the recycle of reactant may be examined. The patent reveals that the catalyst ensures very fast reaction rate. Conversion above 98% may be achieved in a fluid-bed reactor for residence time of seconds. Thus, recycling propylene is not economical. The same conclusion results for ammonia. The small ammonia excess used is to be neutralized with sulfuric acid (30% solution) giving ammonium sulfate. Oxygen supplied as air is consumed in the main reaction, as well as in the other undesired combustion reactions. 

For the Equipment Safety Subindex the process plant area is divided into two different areas, which have different safety properties. The onsite area is the area where the raw materials are converted into the products. This is referred as the inside battery limits area (ISBL). This area is characterized by large number of equipment and piping located in a concentrated way in a small area. The rest of the plant is referred as the offsite or outside battery limits area (OSBL). The offsite area is characterized by large inventories of fluids, which are often flammable and/or toxic. The number of equipment in OSBL area is smaller but their size larger than in the ISBL area. The layout is much more scattered in OSBL than in ISBL which is to enhance safety. 

A plant is divided into inside and offsite battery limit areas. The configurations of ISBL and OSBL areas differ considerably. Generally the size of equipment, the amount of chemicals and also the spacings are larger in OSBL area. The safety of the process structure is also affected by these factors. Therefore this aspect is included also into the database. 

This is a multiplier , which when applied to the purchase prices of major pieces of chemical process equipment, provides an estimate of the installed cost of the chemical process. b ISBL, inside battery limit. c OSBL, outside battery limit. 

Manholes inside process area battery limits should be vented at least 18 in (46 cm) above the highest pipelines or equipment within a 10-ft (3-m) radius or... 

Primary cable trays inside of process areas, process structures, or unit battery limits should be reviewed to determine if their routing or location presents a potential fire exposure. Potential external fire exposures to cable trays are typically at those locations where flammable or combustible liquids or gases are handled, such as ... 

Main banks of aboveground instrument runs in cable trays (such as those coming from the control room and supported on process unit pipe racks) that are located inside process unit battery limits should be considered for fireproofing by one of the following passive methods ... 

Inside battery limit (ISBL) is the limit of the processing facility and the equipment contained therein. 

The investment cost will be given, indicated as ISBL (inside battery limit plant, laboratories, process control system, etc.), OSBL (outside battery limit) or infrastructure costs. It is expected that the OSBL costs for a micro structured reactor plant will be a minor issue as here mainly costs for housing, cooling facilities, etc., are included. 

The input/output structure defines the material balance boundary of the flowsheet Often it is referred as the inside battery limit envelope. A golden rule requires that the total mass flow of all components entering the process must be equal with the total mass flow of all components leaving it. It should be kept in mind that the recycles affect only the internal process streams, but not the input/output material balance. 

Estimated inside battery limits (ISBL) costs based on unit processing 158,000 mtpy of BT reformate feedstock with 68 LV% aromatics (US Gulf Coast site in 2003). 

Economics The solvent used in the Sulfolane process exhibits higher selectivity and capacity for aromatics than any other commercial solvent. Using the Sulfalane process minimizes concern about trace nitrogen contamination that occurs with nitrogen-based solvents. Estimated inside battery limits (ISBL) costs based on a unit processing 158,000 mtpy of BT reformate feedstock with 68 LV% aromatics (US Gulf Coast site in 2003). 

Economics U.S. Gulf Coast inside battery limits are based on processing 15,000 bpsd of C3 to C4 feed. Gas turbine driver assumed for product compressor. 

An important reason for preparing study reports is to determine the capital expenditure (investment) of a project [Muthmann, 1984, Prinzing 1985, DAdda 1997]. This is made up of the location-independent ISBL (inside battery limits) process plant costs such as investment in the production plant and the associated control rooms, laboratories, employee facilities, tank farms, and loading and unloading stations, as well as the location-dependent OSBL (outside battery limits) costs of all the service facilities. 

Based on the described process design, an economic feasibility study has been performed [48]. The total processing costs are calculated from the costs of the process equipment, the chemicals, and the utilities required. In addition, the start-up costs (5% of total fixed capital), maintenance (5% of inside battery limits, a standard term denoting the part of the plant considered), plant overheads (80% of labor costs and 20% maintenance), and capital charges (10 year depreciation) are included in the calculations. As the infrastructure is aheady present at the current polymerization plant, no additional costs are assumed to be incurred outside battery limits. The operators on duty are assumed to handle the extraction process therefore no additional labor costs are made. The purchased costs of the process equipment shown in Table 14.9 were determined using the cost estimation program Chemical Process Equipment Individual Equipment Costing [55]. 

A RON value of 96 is claimed for the alkylate obtained through the Allqr-Clean process. AlkyClean has been presented as a very versatile option to retrofit liquid acid processes, having up to 20% lower inside-battery-limits cost than for a H2SO4 unit and comparable to that for a HF plant. The process is also shown as attractive to revamp gasoline polymerization units, offering a short time for payback (252). 

The initial reaction (1) consumes NaOH and produces both hydrogen gas and an aluminate byproduct. Upon reaching its saturation limit, the aluminate compound decomposes (2) into sodium hydroxide and a crystalline precipitate of aluminum hydroxide. This process is similar to the reactions inside an aluminum battery. 

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