Foul water

TROUBLE PROBABLE CAUSE(S) 4. High inlet temperature. 5. Fouled water jackets on cylinder. 6. Improper lube oil and/or lube rate. 

The output of a foul-water drainage system should discharge into a foul-water or combined drainage system (foul and surface water). Where such a drainage system is not conveniently available and cannot economically be extended to a site, other methods of foul-water disposal will be necessary, either a cesspool or a septic tank. 

The process is used mostly for industrial separations, such as the removal of yeast from beer or the recovery of emulsified cutting oils. It has been proposed as a pretreatment to RO for fouling waters, but the economics do not yet look attractive. 

Discharge to foul water sewer (with the agreement of the appropriate authority). 

Conversely, flocculation implies those aggregation processes effected by the intertwining of fibrous particles, for example in the wool trade, or the entrapment of silt particles in foul water, as above. 

Foul water, reflux drum water, water draw. <175 <350 All S-3 or S-6 6... 

The corrosiveness of foul waters, hydrocarbons over 230°C (450°F), acids, and acid sludges may vary widely. Material recommendations should be obtained for each service. The material class indicated above will be satisfactory for many of these services, but must be verified. 

Wastewater reuse is a good way to reduce overall pollutant loadings. However, water quality is critical in water reuse. The contaminants present must be compatible with the reuse. For example, reuse waters with high solids content are not satisfactory for crude unit desalting. Stripped foul water containing low H2S and ammonia and high concentrations of phenols has essentially no solids. It is suitable for crude unit desalter wash water if the phenols extracted by the crude are subsequently converted by hydroprocessing units into nonphenolic compounds [36]. Some other examples include ... 

Many processes in a refinery use steam as a stripping medium in distillation and as a diluent to reduce the hydrocarbon partial pressure in catalytic or thermal cracking [37]. The steam is eventually condensed as a liquid effluent commonly referred to as sour or foul water. The two most prevalent pollutants found in sour water are H2S and NH3 resulting from the destmction of organic sulfur and nitrogen compounds during desulfurization, denitrification, and hydrotreating. Phenols and cyanides also may be present in sour water. 

Foul water, reflux drum water, water draw, and hydrocarbons containing these waters, including reflux streams < 175 > 175 < 350 > 350 All All S- 3 or S- 6 C-6 b... 

Water and particulates are the source of fuel quality problems such as filter plugging, corrosion, and system component fouling. Water can be removed through salt drying, coalescence, filtration, and good housekeeping. 

In addition to the primary product and by-product streams, sulfur will be present in other streams in the facility. For example, water that is condensed from the product will contain some dissolved sulfur compounds, as will the stack from the boiler house that is required to provide steam for the system. Dissolved sulfur gases will normally be stripped from foul water to the gas streams, but some fixed sulfur (e.g. thiocyanate) may not be attacked until biological oxidation or other water treatment. The sulfur compounds present in the boiler house stack might be recovered to salable products, depending on the flue gas desulfuri-... 

It will be noted that in the separation of gold from silver the aqua fortis used must be free from hydrochloric acid, while in the separation of silver from copper the aqua fortis must have contained hydrochloric acid to have separated the silver as chloride. Paracelsus does not discriminate however. So also the description of the foul waters used... 

Some anecdotal evidence on higher-fouling waters... 

For convenience, the discussion of materials for these various processes is divided into five chapters. Crude units and utilities are discussed in this chapter. FCCs, fluid cokers, delayed cokers, sour water strippers, and sulfur plants are covered in Chapter Two. Desulfurizers, reformers, hydrocrackers, and flue gas are discussed in Chapter Three. Hydrogen plants, methanol plants, ammonia plants, and gas treating are discussed in Chapter Four. Underground piping, pipelines, production equipment, and tankage associated with the refinery industry are covered in Chapter Five. Discussed throughout these chapters are many common environments and equipment (e.g., sour or foul water, distillation, etc.) that appear in the various types of refinery process plants. 

Tube-side, process fluids 1 to 2m/s, maximum 4m/s if required to reduce fouling water 1.5 to 2.5 m/s. 

Reduce waste generation instead of waste treatment. For example, waste/foul water recycle with or without treatment reduces fresh water consumption and also avoids the need to expand waste water treatment plant... 

Wherever possible, re-use existing equipment and/or waste products (for example, use waste hydrocarbon gases as fuel, and use treated fouled water for washing and desalting in petroleum refineries)... 

Increase re-use of treated fouled water Reduce water usage to minimum required Segregate different types of waste water streams and use localized treatment such as coagulation/flocculation followed by ultra/micro filtration/reverse osmosis membrane units. This can recycle 50% of the waste water as fresh water... 

Foul/waste water Steam used will be converted into foul Foul water generation will be little as They do not produce foul... 

Space constraint Require elevated platforms for surface condensers, (semi-) barometric drain pipes for condensate removal, and separators for separating foul water and oil. Non-barometric installation is possible by combining SJEs and LRVPs Surface condensers and elevated structures are not required. Instead, they require closed-loop liquid coolers for reducing water consumption and gas-liquid-liquid separators. They are compact and require less plot space... 

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