The regulatory Japanese leaching test (JLT13) was greatly revised in the year 2013. This report describes the details of the revised contents (leaching process, solid/liquid separation process, chemical analysis, etc.). In particular, it is important for analytical technicians to understand why certain items needed modification. The modified contents are discussed here, with the inclusion of experimental data and scientific reports by the committee of experts who decided upon the changes. After the completion of the revision, an accuracy and precision survey will be conducted for the JLT13 test in 2014.
Following the revision of Verification methods for Industrial wastes containing hazardous substances such as heavy metals (MOE Public notifications No.13 of 1973, JLT13 leaching test) in 2013, the Japan Society of Material Cycles and Waste Management (JSMCWM) now plans to publish a new comprehensive technical book on the testing methods for waste-related materials. The book contains information on the regulatory leaching test (JLT13), testing methods for contaminated soils, recycled materials and end-of-life products such as waste electronic equipment. It compiles flowcharts, precise procedures and important technical issues that need to be taken into consideration in order to help chemical analysts or technicians in the analysis of waste-related materials. This paper provides an in-depth summary of the manual.
Technical examinations and quality assessments regarding analysis of water quality, soil, industrial waste, etc. have been carried out over the past 35 years at Local Independent Administrative Agency Hokkaido Research Organization Industrial Research Institute. A common sample for environmental measurement certification business operators in Hokkaido was also prepared and distributed for the purpose of inter-laboratory comparison. The interlaboratory comparison not only performs the necessary statistical work, but also summarizes the results of analysis and takes questions regarding analyses of environmental measurement certification business operators. The organization has not only answered with the introduction of written reports, etc. but has also conducted examinations when needed. Many questions are raised these days from environmental measurement certification business operators, especially concerning analysis pretreatments. Examination of solid-liquid separation, pretreatment and various instrumental analysis measurements are all introduced, with a focus on the interlaboratory comparison for soil/industrial waste analysis accompanied by the leaching test in the past several years.
In an amendment to the Japanese leaching test (JLT13), several important modifications have been adapted to improve the accuracy of analytical data. From the viewpoint of metal analysis, the change made in the filtration method (use of membrane filter) is the most important point affecting the analytical results of the leaching test. In the present paper, the effect of the filter material on the analytical results of the leaching test was first examined using different types of filter paper (glass fiber filter, mixed-cellulose ester type membrane filter, and hydrophilic PTFE type membrane filter) in leaching tests for incineration fly ash, sewage sludge and sewage sludge incineration ash. As a result, leachate containing a large amount of organic matter (sewage sludge), had hardly been filtered with hydrophilic PTFE type membrane filter, and some metals showed significantly low concentrations in the PTFE-filtered leachate. In addition, some severe interferences in the application of inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) are described for multi element analysis of waste materials including leachate samples.
An amendment to the Japanese Leaching Test (JLT13) was carried out in February 2013. Despite requests to adopt a method that uses an ion chromatograph (IC) system, this spectrophotometric method, which uses mercury-containing reagents, was adopted instead as a test method for organochlorine compounds. The reason why the IC method was rejected is because it cannot measure the sample solution without macrodilution and requires nitric acid in order to neutralize the sodium hydrate generated from a surplus of sodium biphenyl. We, however, have been successful in neutralizing using a carbonic acid that is easily removed by the CO2 suppressor. The sample solution can be measured using the IC system without macrodilution.
Leaching tests are performed to test a specific quality or characteristics of waste matters, recycling materials or soils, in terms of leaching. Besides “compliance tests,” such as JLT13, leaching tests include various “characterization tests” which can reveal much more about the leaching property by changing the type of solvent used or the leaching operation. Overseas, a common approach has been applied in the standardization of leaching tests among different materials such as soil and waste. In Japan, there are several compliance tests defined by the government or by academic societies but it will now be necessary to advance the standardization of these characterization tests by referring to what is being done overseas.
Besides recently the Environmental Safety Quality Inspection Method was proposed by the Japanese Industrial Standardization Committee in order to utilize recycling materials such as slag and coal ash in a more beneficial way. The inspection method is composed of two steps : characterization tests are suited to the first step, Environmental Safety Quality-Type Inspection; and compliance tests are suited to the second step, Environmental Safety Quality Delivery Inspection. Appropriate leaching tests are designated to be assigned in each step.
Policies and testing procedures surrounding leaching test methods that have been regulated by the Soil Contamination Countermeasures Act have many similarities to those of the leaching test method for industrial waste given in the Japanese Environmental Agency, notification No.13. There are, however, several technical issues involved in the leaching tests that are specific to soil; the differences mainly pertain to the physical and chemical properties of soil as compared to industrial waste. This manuscript addresses the technical features and issues of the regulatory leaching test for soil, taking into consideration the recent discussions regarding technical revisions made to the leaching test method for industrial waste in June 2013. In addition, based on the results of a series of leaching tests conducted on five different rock materials containing natural derived lead and/or arsenic, the manuscript also discusses the effects of their friability and grain size on the amount of leaching exhibited by trace metals in the conventional batch-type leaching tests. Finally, state of the art technology in leaching test methods for soils and rocks in Japan are reviewed in order to put forth future roles and perspectives relating to a regulatory leaching test for soil.
Generally, a heavy metal fixative is used for the treatment of incinerator fly ash to immobilize the heavy metal in it. On the other hand, flue gas treatment chemicals contain alkali, which is applied to neutralize the acidic chemicals in the fly ash. Excess flue gas treatment chemicals remain in the fly ash as unreacted alkalis. When chemicals are applied as a heavy metal fixative for fly ash, the remaining unreacted alkali have a negative effect on the reaction of the chemicals and the fly ash. In this paper, we realized the optimization of flue gas and fly ash treatment with a novel flue gas treatment chemical and an inorganic phosphate heavy metal fixative. In particular, decreasing the application rate of the inorganic phosphate heavy metal fixative was achieved by dramatically decreasing (by over 50 %) the alkalinity of the fly ash through the application of this novel flue gas treatment chemical. In addition, our optimized treatment improved the stability of the heavy metal immobilization in the treated fly ash in comparison with a conventional treatment using lime as the flue gas treatment chemical and organic chelate as the heavy metal fixative.