Abstract:
Coke wastewater is a complex industrial wastewater due to its high content of toxic compounds such as cyanides, thiocyanates, phenols, tar, oils, and fats. After a series of treatments, wastewater with a high ammonium content is obtained (around 4,150 mg·L-1). A stripping process is used to reduce it. Certain pollutants in the influent, such as tar, polycyclic aromatic hydrocarbons (PAHs), oils, fats and total suspended solids (TSS), interfere with stripping and therefore must be previously removed. In this study, the performance of a pilot-scale airlift sand filter was evaluated under real conditions for the reduction of the concentration of tar, PAHs, oils, fats and TSS, before stripping. Prior to the sand filter, a cationic flocculant was added to the influent (2 ppm). High (10 mm.min-1), medium (7.5 mm.min-1) and low sand speeds (1.9-2.6 mm.min-1) were assessed. The latter conditions gave the best results: a decrease of 98.2% in TSS, 99.7% in oils, fats and grease and 97.6% in PAHs. The final effluent (≤ 1.6 mg PAHs·L-1, ≤ 5 mg TSS·L-1 and ≤ 0.05 mg·L-1 of fats, oils and grease) was suitable for the stripping process.
摘要:
焦炭废水是一种复杂的工业废水,由于其氰化物等有毒化合物含量高,硫氰酸盐,酚类物质,tar,油,和脂肪。经过一系列的治疗,得到含铵量较高的废水(约4,150mg·L-1)。使用剥离工艺来减少它。进水中的某些污染物,比如tar,多环芳烃(PAHs),油,脂肪和总悬浮固体(TSS),干扰剥离,因此必须事先清除。在这项研究中,在实际条件下对降低焦油浓度的中试空运砂过滤器的性能进行了评估,PAHs,油,脂肪和TSS,在剥离之前。在砂滤器之前,向流入液中加入阳离子絮凝剂(2ppm)。高(10毫米。min-1),中等(7.5毫米。min-1)和低沙速度(1.9-2.6毫米。min-1)进行了评估。后一种条件给出了最好的结果:TSS降低了98.2%,99.7%的油,脂肪和油脂和97.6%的PAHs。最终流出物(≤1.6mgPAHs·L-1,≤5mgTSS·L-1和≤0.05mg·L-1的脂肪,油和油脂)适用于汽提过程。