Chemical Engineering and Inorganic Chemistry Department, ETSIIT, University of Cantabria, Avda los Castros, Santander, Spain.
J Hazard Mater. 2010 May 15;177(1-3):428-36. doi: 10.1016/j.jhazmat.2009.12.050. Epub 2009 Dec 16.
The application of solvent-based paints by spraying in paint booths is extensively used in a wide range of industrial activities for the surface treatment of a vast array of products. The wastes generated as overspray represent an important environmental and managerial problem mainly due to the hazardous characteristics of the organic solvent, rendering it necessary to appropriately manage this waste. In this paper a solidification/stabilization (S/S) process based on accelerated carbonation was investigated as an immobilization pre-treatment prior to the disposal, via landfill, of an alkyd solvent-based paint waste coming from the automotive industry; the purpose of this S/S process was to immobilize the contaminants and reduce their release into the environment. Different formulations of paint waste with lime, lime-coal fly-ash and lime-Portland cement were carbonated to study the effect of the water/solid ratio and carbonation time on the characteristics of the final product. To assess the efficiency of the studied S/S process, metals, anions and dissolved organic carbon (DOC) were analyzed in the leachates obtained from a battery of compliance and characterization leaching tests. Regarding the carbonation of paint waste-lime formulations, a mathematical expression has been proposed to predict the results of the leachability of DOC from carbonated mixtures working at water/solid ratios from 0.2 to 0.6. However, lower DOC concentrations in leachates (400mg/kg DOC in L/S=10 batch leaching test) were obtained when carbonation of paint waste-lime-fly-ash mixtures was used at 10h carbonation and water to solid ratio of 0.2. The flammability characteristics, the total contents of contaminants and the contaminant release rate in compliance leaching tests provide evidence for a final product suitable for deposition in non-hazardous landfills. The characterization of this carbonated sample using a dynamic column leaching test shows a high stabilization of metals, partial immobilization of Cl(-), SO(4)(2-), F(-) and limited retention of DOC. However, the obtained results improve the previous findings obtained after the paint waste S/S using uncarbonated formulations and would be a useful pre-treatment technique of the alkyd paint waste prior to its disposal in a landfill.
在广泛的工业活动中，通过喷涂在喷漆室内应用溶剂型涂料，广泛用于处理各种产品的表面。过喷产生的废物是一个重要的环境和管理问题，主要是由于有机溶剂的危害性，因此需要对其进行适当的管理。本文研究了一种基于加速碳酸化的固化/稳定化（S/S）工艺，作为一种预处理方法，用于对来自汽车工业的醇酸溶剂型涂料废物进行处置（通过垃圾填埋场）；该 S/S 工艺的目的是固定污染物并减少其向环境中的释放。对含有石灰、石灰-粉煤灰和石灰-波特兰水泥的不同配方的涂料废物进行碳酸化，以研究水/固比和碳酸化时间对最终产物特性的影响。为了评估所研究的 S/S 工艺的效率，从一系列符合法规和特性浸出测试的电池中分析了浸出液中的金属、阴离子和溶解有机碳（DOC）。关于含石灰涂料废物的碳酸化，已经提出了一个数学表达式，用于预测在水/固比为 0.2 至 0.6 的碳酸化混合物中 DOC 的浸出率的结果。然而，当在 10 小时碳酸化和水/固比为 0.2 的情况下使用含石灰-粉煤灰混合物进行碳酸化时，浸出液中的 DOC 浓度较低（L/S=10 批浸出试验中的 400mg/kg DOC）。在符合法规的浸出试验中，可燃性特性、污染物的总含量和污染物释放率为适合沉积在非危险垃圾填埋场的最终产物提供了证据。使用动态柱浸出试验对碳酸化样品进行的特性分析表明，金属的稳定性高，Cl(-)、SO(4)(2-)、F(-)部分固定，DOC 的保留有限。然而，与使用未经碳酸化的配方进行 S/S 处理后的先前发现相比，得到的结果有所改善，并且对于在垃圾填埋场处置之前对醇酸涂料废物进行预处理是一种有用的技术。
