The goal of natural gas processing is to produce pipeline quality gas that can be delivered to end-users. Like oil refining, the processing of natural gas leads to the production of a large number of by-products that are also used as fuels or that constitute the manufacture of petrochemicals. The value of these by-products can be important from an economic point of view, and much of petrochemical development in the Middle East is based on by-products of natural gas processing. Asphalt company: The asphalt company uses limestone from the stone company and residual oil from the refinery to produce asphalt for use on surrounding roads. A refinery contains one or more gas processing units to separate the weak components contained in crude oil (butane and light) (butane and light) into individual components or groups of components needed for products or as raw materials to other units. The Citgo refinery was the largest spill in louisiana state history. The Federal Environmental Protection Agency and Louisiana`s Department of Environmental Quality sued Citgo in 2008 for negligently neglecting to maintain rainwater tanks and failing to maintain sufficient stormwater storage capacity at their refinery. In September 2008, Citgo pleaded guilty and was ordered to pay US$13 million, the largest fine ever imposed for a criminal offence under the Clean Water Act. This complaint generated more than 200 additional complaints against Citgo for the spill. Refineries are experiencing a significant increase in hydrogen requirements to improve product quality and treat heavy acid oils. Hydro-processing and saturation of aromatics and olefins will accelerate the demand for hydrogen in the refinery.

Catalytic reform of naphtha alone is not able to meet the refinery`s hydrogen needs. A study of global refining showed that additional refinery hydrogen capacity, produced primarily by steam methane reform, reached 337 million m3/day (11,880 million m3/day-MMcfd) in 2002, up from 110 million m3/day in 1990. There is a growing recognition that there will be a significant shortage of refinery hydrogen in the future. Specific hydrogen production units, such as steam methane reformers or those that perform partial oxidation of heavy residues, must be built. Refining projects are generally far too large to be built after a single construction contract. As a general rule, there are several contracts with contractors for certain parts of the facility. These different contract packages typically cover certain elements of the refinery, including basic refining process units, certain licensed technology packages, distribution companies, infrastructure, etc. Managing multiple contracts with different consortia is a complex undertaking and, therefore, strong integrated project management teams are an essential feature of refinery project development. The issues that need to be addressed in construction and development contracts for refining projects are similar to those related to other processing projects and are discussed in more detail in Chapter 12.