Green field processes

Design of catalytic reaction fields toward green chemical processes... 

GCES allows users to build a green chemical process, design a green chemical, or survey the field of green chemistry. The system is equally useful for new and existing chemicals and their synthetic processes. The GCES features are contained in five modules ... 

This order of magnitude estimate is based on a hypothetical plant for the production of 500 kt/year of ethylene with a capital cost of 150 million. This is compared to the cost of a green-field ethane cracker of about 700 million. Process selectivity is assumed 100% with operating allowance for feed and fuel of 5.5% and 3% respectively. 

The capital costs are developed for green-field projects completely isolated from other facilities. All the costs associated with utilities (unless otherwise accounted) are allowed for in the capital cost. Some processes require small amounts of power. This is considered as an import. 

The majority of User Requirements for a DCS are likely to be common, regardless of whether the DCS is for a brown or green field application. A basic requirement that needs to be determined is the level of automation to be provided. For DCS systems this can vary from providing essentially remote manual operation of plant units to automation of individual process operations within units, finally leading to automation of all operations and transfers across process units within a process cell. 

The capital cost required for the provision of utilities and other plant services will depend on whether a new (green field) site is being developed, or if the plant is to be built on an existing site and will make use of some of the existing facilities. The term battery limits is used to define a contractor s responsibility. The main processing plant, within the battery limits, would normally be built by one contractor. The utilities and other ancillary equipment would often be the responsibility of other contractors and would be said to be outside the battery limits. They are often also referred to as off-sites . 

The flameless oxidation can be adopted where a suifable flue-gas recirculation af high temperature of flue gases can be carried out These conditions can be fulfilled by numerous heaf process planfs wifhouf modifications of the plant That is, the existing burners can often be modified and adapted to flameless oxidation. In ofher processes, especially fhose af low femperafure, the whole plant has been adapted on purpose, which is worth doing in green field construction only. 

The studies were carried out under contract by KSLE (ICilbom SNC Lavalin Europe) in 1997/8 aided by specialist input from ISP Ltd. on the zinc condensation section and VacMetals on the RH matte pump. The designs took into account all process and ancillary plant equipment for a green field site plant. 

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