Tham khảo tài liệu 'lubricants and lubrication part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Metalworking Fluid Circulation System 497 Petroleum Ether-extractable Components The presence of petroleum hydrocarbons are most often determined by extraction with petroleum ether. However it should be remembered that other products may also be extracted. Exact determination of hydrocarbon content requires another analytical step . chromatography . Petroleum ether extractables have been divided up into saponifiable and non-saponifiable components. Thresholds and Legislation There are no national guidelines on the quality of separated-water in Germany and in Britain which can assist the operator of cutting fluid separation plants. Thresholds are set by local water authorities which can also reflect the local situation regarding waste water treatment plants and the condition of rivers and streams. This leads to greatly differing evaluations between areas. Apart from BOD5 and COD and petroleum ether extractables pH value insoluble solids a series of metals and ions such as sulfate cyanide and nitrite have thresholds. As regards the latter the importance is either their toxicity or as in the case of sulfate the damage it causes to concrete pipes and drains. In Germany national legislation only applies indirectly to water separated-out of emulsions. Among other things the German Law on Water regulates the disposal of wastes into public sewers and rivers the notification obligation if petroleum products are stored or the location of protected water zones. German Waste Disposal Law deals with the treatment of sludges which remain after emulsion separation processes. This includes incineration land-fill and special land-fill sites for hazardous wastes. The German Law on Emissions is focussed on keeping the air clean. As regards disposal of cutting fluids this is limited to incineration of separated oils and used emulsions. Extreme Pressure EP agents with high levels of sulfur and chlorine can be problematic. Waste Oil Provisions whose focal point up to now was .
