Petrochemical complex

Butylenes are C Hg mono-olefin isomers 1-butene, <7j -2-butene, trans-2-huX.en.e and isobutylene (2-methylpropene). These isomers are usually coproduced as a mixture and are commonly referred to as the fraction. These fractions are usually obtained as by-products from petroleum refinery and petrochemical complexes that crack petroleum fractions and natural gas Hquids. Since the fractions almost always contain butanes, it is also known as the B—B stream. The linear isomers are referred to as butenes. 

Compounds considered carcinogenic that may be present in air emissions include benzene, butadiene, 1,2-dichloroethane, and vinyl chloride. A typical naphtha cracker at a petrochemical complex may release annually about 2,500 metric tons of alkenes, such as propylenes and ethylene, in producing 500,000 metric tons of ethylene. Boilers, process heaters, flares, and other process equipment (which in some cases may include catalyst regenerators) are responsible for the emission of PM (particulate matter), carbon monoxide, nitrogen oxides (200 tpy), based on 500,000 tpy of ethylene capacity, and sulfur oxides (600 tpy). 

Single train availabilities must be at least 90% for utility applications and greater than 97% for refineries and petrochemical complexes. 

Olefin isomerization reactions range from some of the most facile using acid catalysts to moderately difficult and, as components of more complex reaction schemes such as catalytic cracking, may be among the most common reactions in hydrocarbon processing. As stand-alone reactions, they are primarily used to shift the equilibrium between terminal and internal olefins or the degree of branching of the olefin. While olefin isomerization was considered for the production of MTBE, today stand-alone olefin isomerization processes are only considered for a few special situations within a petrochemical complex. 

Analysis of Esso Longford as well as analysis in the UK Health and Safety Executive (HSE) investigation report into petrochemical complex major incidents all show that common underlying causes are often repeated. The Longford incident clearly illustrates the multiple root cause concept. A number of PSM system failures occurred either in... 

A relatively new design of a high-rate DAF unit uses a shallow bed system (Supracell) with only 3 minutes of retention time and operated at an overflow rate of 140Lpm/sqm (3.5 gpm/sq ft) [42]. This unit has been used for industrial and municipal wastewater treatment and offers lower capital cost and headroom requirements. It was installed at a petrochemical complex in Texas as a secondary clarifier to improve the operation and the capacity of an existing activated sludge system [43]. In recent years, nitrogen has replaced air in covered DAF systems because of the potential for explosion. These systems are called dissolved nitrogen flotation (DNF) systems. The operations of DAF and DNF are similar. 

Anon (1998) Petrochemical complex shields refining profits, Oil and Gas Journal, 96, 31. 

In this section we demonstrate the performance of the proposed model on an industrial-scale case study. Instead of considering the full scale petrochemical network which may have limited application, we consider a special case of the integration problem. Although the proposed formulation covers the full scale refinery network and petrochemical systems, the case study will consider the integration of a petrochemical complex for the production of polyvinyl chloride (PVC) with a multi-refinery network. PVC is one of the major ethylene derivatives that has many important applications and uses, including pipe fittings, automobile bumpers, toys, bottles and many others (Rudd et al., 1981). 

The petrochemical complex for the production of P VC starts with the production of ethylene from the refineries feedstocks. The main feedstocks to the ethylene plant in our study are light naphtha (LN) and gas oil (GO). The selection of the feedstocks and, hence, the process technologies is based on the optimal balance and trade-off between the refinery and petrochemical markets. The process technologies considered in this study for the production of PVC are list in Table 5.2. The overall topology of all petrochemical technologies for PVC production is shown in Figure 5.3. 

Table 5.2 Major products and process technologies in the petrochemical complex.

Figure 5.3 SEN representation of the PVC petrochemical complex possible routes.

The model was then solved for the total refinery network and the PVC petrochemical complex. As shown in Table 5.4, the proposed model redesigned the refinery network and operating policies and also devised the optimal production plan for the PVC complex from all available process technologies. The model selected gas oil, an intermediate refinery stream, as the refinery feedstock to the petrochemical complex as opposed to the normally used light naphtha feedstock in industrial practice. In fact, this selection provided the optimal strategy as the light naphtha stream was used instead in the gasoline... 

In this study, operational risk was accounted for in terms of variance in both projected benefits, represented by first stage variables, and forecasted demand, represented by the recourse variables. The variability in the projected benefit represents the solution robustness where the model solution will remain close to optimal for all scenarios. On the other hand, variability of the recourse term represents the model robustness where the model solution will almost be feasible for all scenarios. This approach gives rise to a multiobjective analysis in which scaling factors are used to evaluate the sensitivity due to variations in each term. The projected benefits variation was scaled by 0i, and deviation from forecasted demand was scaled by 02, where different values of 0i and 02 were used in order to observe the sensitivity of each term on the final petrochemical complex. The objective function with risk consideration can be written as follows ... 

Table 9.4 depicts the results of the optimal integration network between the three refineries and the PVC petrochemical complex. As shown in Table 9.4, the proposed... 

Fig. 1. Interlocking processes and flow of materials in a representative petrochemical complex. (UOV, Inc)...

Microprocessor-based control systems are marketed under a variety of acronyms and not all will be true DCCSs. Of particular note are the Supervisory Control and Data Acquisition (SCADA) systems which form an increasingly central part of the operations of many industries (e.g. offshore oil and gas platforms, petrochemical complexes, pulp and paper works). SCADA describes a communications system whose principal function is to join instrumentation and control into a cohesive package(57) and, particularly, the supervision and management of remote ... 

The average particulate concentration in micrograms per cubic meter for a station in a petrochemical complex was measured every 6 hours for 30 days. The resulting data are given in table. 

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