{"id":482,"date":"2023-10-24T15:21:05","date_gmt":"2023-10-24T06:21:05","guid":{"rendered":"https:\/\/environ.kit.ac.jp\/en\/?page_id=482"},"modified":"2025-08-08T11:03:26","modified_gmt":"2025-08-08T02:03:26","slug":"inorganic-liquid-waste-2","status":"publish","type":"page","link":"https:\/\/environ.kit.ac.jp\/en\/inorganic-liquid-waste-2\/","title":{"rendered":"Inorganic Liquid Waste"},"content":{"rendered":"\n

Inorganic liquid waste treatment at Center for Environmental Science<\/h2>\n\n\n\n
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Our college began on-campus disposal of inorganic liquid waste in 1980.<\/p>\n\n\n\n

In 2002, the treatment facility was upgraded and the treatment method was changed from the neutralizing coagulation method to the iron powder method<\/strong>.<\/p>\n\n\n\n

This facility has treated more than 20,000 liters of flue gas flushing wastewater from organic liquid waste treatment facility on campus, in addition to inorganic liquid waste discharged from laboratories.<\/p>\n\n\n\n

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The iron powder method <\/strong>is a method for recovering heavy metals from liquid waste by precipitating heavy metals with iron powder having reducing ability and coagulating them with dissolved iron ions.<\/p>\n\n\n\n

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Inorganic liquid waste treatment facility on campus
2002-2022<\/figcaption><\/figure>\n<\/div>\n<\/div>\n\n\n\n

After more than 40 years of on-campus treatment of inorganic liquid waste, in 2017 we shut down organic liquid waste treatment facility and began outsourcing disposal of organic liquid waste, resulting in a significant decrease in the amount of inorganic liquid waste treated.<\/p>\n\n\n\n

Additionally, due to the aging of the inorganic liquid waste treatment facility, in 2022 we terminated our on-campus inorganic liquid waste treatment.<\/p>\n\n\n\n

From 2023, the collection, transportation, and disposal of inorganic liquid waste will be outsourced to licensed contractors.<\/p>\n\n\n\n

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Flow of inorganic liquid waste treatment<\/h2>\n\n\n\n

Separation and storage of inorganic liquid waste<\/strong><\/p>\n\n\n\n

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\u25bc<\/span><\/p>\n<\/div>\n\n\n\n

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In each laboratory, inorganic liquid waste should be stored in following six categories according to the substances it contains.<\/p>\n<\/div>\n<\/div>\n\n\n\n\n\n\n\t\n\n\t\n\t\n\t\n\t\n\t\n\t
<\/td>containing substances<\/th>\n<\/tr>\n<\/thead>\n
I. <\/td>hazardous heavy metal compounds; Cr, Pb, Se, Cd, As
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II. <\/td>general heavy metal compounds<\/td>\n<\/tr>\n
III. <\/td>inorganic acids<\/td>\n<\/tr>\n
IV.<\/td>inorganic alkalis<\/td>\n<\/tr>\n
V.<\/td>cyanide compounds<\/td>\n<\/tr>\n
VI. <\/td>organic and\/or inorganic mercury compounds<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\n

Storage precautions<\/h4>\n\n\n\n