En-Tech Research Institute Inc.

Kanegafuchi Kagaku Kogyo Kabushiki Kaisha

Polution Sciences Laboratory Incorporated

Tomio Nishida

Taiichiro Sasae

Masakazu Uekita

Takashi Funahashi

Masanori Oshima

Kazuya Katayama

A waste-treating material which comprises cement and at least one reducing metal, effective for stabilizing industrial wastes containing harmful metals like a heavy metal and the like and cyanides. A preferred example of the reducing metal is iron. Additionally the waste-treating material may also contain at least one member selected from a group consisting of a reducing agent, aluminum sulfate, allophane, and bentonite as the auxiliary. The use of this waste-treating material makes it possible to stabilize the hazardous heavy material and the cyanides contained in the industrial wastes, thereby remarkably contributing to a stabilizing treatment of the industrial wastes.

Waste-treating material

The present invention provides an immobilizing agent for making harmless the detrimental metals contained in fly ash formed from an urban dust incinerating plant and a method for immobilizing the fly ash. The treating agent according to the present invention contains .alpha. starch and/or dextrin (component A), sodium silicate and/or a hydrogen phosphate compound (component B) and an allophane having a molecular ratio of SiO.sub.2 /Al.sub.2 O.sub.3 of not lower than 2 (component C). It may also further contain cement, bentonite, calcined gypsum and fly ash formed from a coal thermoelectric power plant. The mixing ratio of the components A, B and C is preferably 100 parts by weight: 20 to 160 parts by weight: 40 to 180 parts by weight respectively. The treating agent is mixed with the above-mentioned fly ash and water is added to it and the mixture is milled and then used. The treating agent of the present invention can enclose detrimental metals stably with no second elution and thus is effective for immobilizing treatment.

Treating agent for making harmless and immobilizing fly ash containing

The immobilization agent for industrial waste according to the present invention is characterized by that it contains cement, ferrous chloride, iron oxalate and amorphous aluminium silicate, and it is preferred said ferrous chloride, iron oxalate and amorphous aluminium silicate are contained in it by mixing ferrous chloride and iron oxalate with amorphous aluminium silicate and granulating and heating the mixture in an inert gas stream. Further, according to the present invention, it may also contain at least one selected from the group consisting of potassium chloride, magnesium chloride, sodium chloride, cobalt chloride, aluminium sulfate, citric acid, calcium chloride and sodium sulfate in addition to the compounds mentioned above.

Immobilization agent for industrial waste

Growing community of inventors

Nagaokakyo, Japan

Tomio Nishida