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Source
Organic matter makes up a significant part of the soil, therefore water-soluble
organic compounds are present in all water supplies. Organic matter is reported
on a water analysis as carbon, as it is in the TOC (total organic carbon)
determination. The following is a list of organics, which regulated under the
Safe Drinking Water Act of 1986.
Endrin异狄氏剂
Trichloroethane三氯乙烷
Lindane林丹
Tetrachlorodibenzodioxin (dioxin)二恶因类的四氯戴奥辛
Methoxychlor甲氧滴滴涕
Vydate p甲氨叉威、万强，草安威，草肟威p
Toxaphene毒杀芬
Simazine西玛津
Polynuclear aromatic hydrocarbons (PAH)多环芳烃
TP总磷
Polychlorinated bi phenyls (PCB)多氯联苯
Aldicarb 涕灭威
Atrazine 莠去津
Chlordane氯丹
Phthalates苯二甲酸盐或酯类
Dalapon茅草枯
Acrylamide丙烯酰胺
Diquat敌草快
Dibromochloropropane (DBCP)二溴氯丙烷
Endothall草藻灭
Dichloropropane二氯内烷
Glyphosate草甘膦
Pentachlorophenol五氯苯酚
Carbofuran 克百威
Picloram毒莠定
Alachlor甲草胺
Dinoseb地乐酚
Epichlorohydrin表氯醇
Ethylene dibromide (EDB)二溴化乙烯
TolueneDibromomethane
Adipates己二酸
Xylene Hexachlorocyclopentadiene
Organics come from three major sources: (1) the breakdown of naturally occurring
organic materials, (2) domestic and commercial chemical wastes, and (3) chemical
reactions that occur during water treatment processes. The first source is
comprised of humic materials, microorganisms, and petroleum-based aliphatic and
aromatic hydrocarbons. Organics derived from domestic and commercial chemical
wastes include wastewater discharges, agricultural runoff, urban runoff, and
leaching from contaminated soils. Organic contaminants formed during water
treatment include disinfection by-products such as THM抯 (Trihalomethanes), or
undesirable components of piping assembly such as joint adhesives.
Treatment
Activated carbon is generally used to remove organics, color, and taste-and-odor
causing compounds. The contact time and service flow rate dictate the size of
the carbon filter. When removing organics, restrict flow rates to 2 gpm per
square foot of the filter bed. Reverse osmosis will remove 98 to 99% of the
organics in the water. Ultrafiltration (TJF) and nanofiltration (NF) have both
been proven to remove organics. Anion exchange resin also retains organics, but
periodically needs cleaning.
