Skid-mounted plants

An industrial grade, skid-mounted unit (see Fig. 11.2) has been operating successfully at Occidental Chemical s Delaware City mercury cell plant since September 1997. Operating results have met both the expectations of the client and Kvaerner. This chapter discusses the operating experience at OxyChem and the resulting optimised commercial product, the Kvaerner Chemetics Sulphate Removal System or SRS . The acceptance in the market-place has been excellent four systems have been ordered and three are in the process of manufacture, with operations commencing later in 2000. Approximately 50 firm price proposals have been issued in the past two years. Several of these evaluations are in the final stages and will lead to the sale of units in the near future. 

Figure 5.19 Skid-mounted reverse osmosis plant able to produce 700 000 gal/day of desalted water. Courtesy of Christ Water Technology Group...

Figure 3. Equipment to blend and apply sulfur composites in the field. (top) Trailer-mounted, commercial spray unit used to prepare and apply up to 500 gal of composite per batch. (bottom) Skid-mounted batch plant has a capacity of 1500 gal of composite per batch. Composite can be transferred to mobile spray units or used directly from the mixing tanks.

A skid-mounted batch plant complete with steam boiler and generator was placed on a flatbed trailer and was positioned adjacent to the site. Composite was prepared from slate sulfur and was sprayed directly onto the basin. Instantaneous spray rates were about 400 lb/min. 

The top layer is the procedural layer and this generally defines how unit operations are combined across plant units for the overall process. A feature of S88 is the ability to generate equipment modules, essentially common arrangements of control modules to provide a specific function (e.g., skid-mounted temperature control units for reactors or valve/pump arrangements for transfer routes). 

Phillips, S.G. Skid-mounted pilot-plant facilities. Chem. Eng. Prog. 1990, 15. 

Main plant items (MPI). These include aU major process- and utility-related equipment. Major includes pumps, fans, in-line filters, and installed spare equipment but excludes valves, piping, fittings, pipe hangers, heat tracing, lighting, vents, hoists, interlocks, breakers, and starter panels. Skid-mounted packages are considered to be one MPI. 

In late 1972 the three companies announced plans to demonstrate the commercial feasibility of the citrate process. The prime objective was to generate hard engineering and economic data. Basically, Peabody was to fabricate and assemble a skid-mounted 2000 SCFM unit to McKee s design specifications with Pfizer providing chemical expertise, citric acid, and initial host operation of the unit on the power plant in their Terre Haute, Indiana plant site. Since June 1973, when the Terre Haute unit... 

This is a method introduced fairly recently that suits continuous operation particularly well, such as is common in paper, metal coil and fabric coating. Ideally it should be part of the original equipment since it needs to exclude air (as a source of oxygen) from the evaporation zone and this is a function not easily retrofitted to existing plant. It is very compact so that space near the evaporation zone, often very limited, is kept to a minimum. A measure of the problem is that a skid-mounted module with a plot area of 3 m by 2 m and an overall height of 3.75 m has a solvent capacity of 4501/h (Fig. 2.10). 

All the methods can be applied to continuous or batch plants and, particularly for the latter, skid-mounted package units are available in some cases (Figs 5.1 and 5.2). Although the principles of operation may seem simple, the handling of non-Newtonian tars and polymers can prove difficult and the know-how of plant manufacturers in this field is valuable. 

In addition, the skid-mounted serial installations concept (sometimes called modular) was practically applied. The installations are constructed on a platform or barge at the builder s site and transported in nearly com--pleted form to the operating site. This avoids the problem of a small-scale plant being constructed in a remote place without the necessary industrial infrastructure. Standardized plants using skid-mounting will have a positive impact on ... 

We would need to check whether the vendor can supply the whole unit as a skid-mounted type. If not, the vendor should inform the overall space required for the plant. 

The study, one of the first to examine a complete plant from the PI viewpoint, looked at wet air oxidation of phenol, a contaminant regularly found in industrial effluent streams. The plant considered handles lOmVh of effluent with a phenol concentration of 10 ppm. A flow sheet model was used to produce material and energy balances, allowing individual equipment items to be sized and costed (Anon, 1994 Reay, 1999). Two intensified plant layouts were considered, one of which was skid-mounted. (The latter concept is feasible if the oxygen storage and effluent holding facilities are located separately.)... 

The viability of the Lurgi MTF process was first demonstrated at a unit operated jointly with Statoil at Statoil s methanol plant in Norway [49] from 2001 to 2004. The skid-mounted MTP unit comprised of three reactors used 360kg/day methanol feed per reactor. In 2003, to confirm the quality of the propylene obtained in the MTP demonsfration unit, samples were sent to Boreahs s hmovation center in Rpmiingen, Norway, where it was polymerized with Boreahs s Borstar process to a polypropylene that met all specifications, and converted into thermoformed cups. The results from the demonsfration and further tests proved that the MTP catalyst Ufe exceeds 1 year of operation. The results also showed that the zeoUte-based catalyst could be easily regenerated more than a dozen times. 

The design of cyclonic scrubbers is usually based on pilot tests, experience with units in similar service and empirical correlations rather than any fundamental model of absorption or particle collection performance. A skid mounted test unit, similar to that shown in Fig. 13.3.6, can give plant personnel a very good indication of the expected performance of a commercial scale unit. 

Polylactic acid (PLA) PLA biodegradable thermoplastic polyester produced from lactic acid is the commercially most advanced bioplastic. Biophan produces foils made of PLA produced by Nature Works in Blair, Nebraska, for vegetable and fruit packaging. Sulzer [54] has developed a new process to convert lactates to PLA with an entirely skid-mounted unit. A1000 ton continuous demonstration pilot plant for PLA was built in Winterthur and Pfaffikon in Switzerland in cooperation with Purac (a lactic acid producer) and Synbra [55], which started commercial PLA polymerization in 2011. Teijin in Matsuyama, Japan, developed a PLA-based heat-resistant biopolymer called Biofront [56]. But it remains an economically challenging business. Cereplast (OK), a maker of various bioplastics and production capacities of over 80 000 tons per years with plants in Assisi (Italy) and Seymour (United States), had to... 

Code of Practice No. 4, Safe and Satisfactory Operation of Propane-Fired Bitumen Boilers, Mastic Asphalt Cauldrons/Mixers, and Hand Tools Code of Practice No. 7, Storage of Full and Empty LPG Cylinders and Cartridges Code of Practice No. 9, LPG-Air Plants Code of Practice No. 10, Recommendations for Safe Handling of LPG in Small Trailer Mounted Vessels, Skid Tanks and Small Bulk Storage Vessels Permanently Attached to Mobile Gas-fired Equipment... 

Portable batch plants have also been built to melt and blend composites on-site. These are useful for larger applications where multiple batches of composite are required. One such unit, built and maintained in Canada, consists of two steam-heated vessels mounted on a common skid. They can be used to convert sulfur into composites or to melt preblended composite delivered to the site in solid form. The vessels have capacities of 1500 and 800 gal. The pump and manifold system has a dual function to transfer sulfur and composite to and from the vessels or to spray-apply composite directly from the tanks via heated hoses. 

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