Process for treating phosphided slags

• Main Authors: RIBOUD, PAUL-VICTOR, GATELLIER, CHRISTIAN
• Format: Patent
• Language: English; French; German
• Published: 15.12.1982
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATERTREATMENT OR WASTE MANAGEMENT; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MANUFACTURE OF IRON OR STEEL; METALLURGY; METALLURGY OF IRON; PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OFWROUGHT-IRON OR STEEL; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS

Procédé de traitement de laitiers phosphurés obtenus par affinage d'un bain de métal en fusion, tel que l'acier. Le procédé selon l'invention consiste à oxyder à chaud le laitier en lui incorporant après affinage un adjuvant solide pulvérisé fortement oxydant et aisément fusible au contact du laitier. Parmi les adjuvants utilisables figurent de préférence les carbonates de métaux alcalins ou alcalino-terreux, et en particulier le carbonate de sodium qui, de surcroît, est un produit couramment utilisé dans le domaine de l'élaboration des métaux, notamment en sidérurgie. L'invention assure une passivation rapide du laitier en stabilisant les phosphures sous forme de phosphates et permet ainsi d'éviter un dégagement de phosphine très toxique qui se produirait naturellement par hydrolyse à froid. Process for the treatment of phosphuretted slag obtained by refining a molten bath, such as steel. The process according to the invention involves hot oxidizing the slag into which is blended, after refining, a pulverized solid adjuvant, strongly oxidizing and easily fusible upon contact with the slag. Among utilizable adjuvants, the carbonates of alkaline metals or alkaline earth metals are preferred, in particular sodium carbonate, which additionally, is a product currently utilized in the domain of the elaboration of metal, notably in iron metallurgy. The invention ensures a rapid passivation of the slag in stabilizing the phosphorus by forming phosphate and allowing in this manner the avoidance of the liberation of very toxic phosphenes which are produced naturally by cold hydrolysis.