Accelerate environmental protection process, stimulative cement kiln is used be
From;    Author:Stand originally
Cement kiln uses an environment the development history that friendly and basic fireproof material turns fireproof material to already had 10 one's remaining years without chromium namely. Cement is the fundamental material that national economy builds, fireproof material is the heart of cement kiln furnace, the change of socioeconomy is deciding the development of cement industry, and the technology that the development of cement industry is affecting cement kiln to use fireproof data again progresses. The requirement that cement kiln wants to have cement industry with the development of fireproof material serves as motivation, also should depend on at the same time already some foundations, and equip new raw material, new technology, newly appear; Other industry situation and relevant course positive result also are affecting the progress of science and technology of fireproof material. These are the masterstroke that the analysis studies to cement kiln uses fireproof material to develop.

The contaminative problem of magnesian chromic brick

Magnesian chromic brick contains 10% ~ the chromic ore of 20% . Chromium gifts the sex of the skin that hang kiln with fireproof good stuff, can lower heat conduction rate, make cement plant obtains considerable economic benefits, but can produce chromic social effects of pollution. Be in high temperature, alkaline when existing with oxidisability atmosphere, partial Cr3 can be changed into Cr6, volatilize and condense in the Leng Duan of fireproof material. Brick of magnesian chromic incomplete contains 0.1% ~ the Cr6 of 0.5% , relative standard stipulates Cr6 allows content (Kg/L) for 1.0-6 ~ 0.01, because brick of this magnesian chromic incomplete is right environmental pollution is very serious. Follow environmental protection code build and do not have chromium

The development of material, the dosage of magnesian chromic brick will decrease greatly.

Kiln of cement of our country some 4000t/d year disassemble brick of magnesian chromic incomplete 180 tons, discharge Cr6 to the environment in all 180 kilogram. To make environmental water reachs IV grade level (Cr6 <0.05mg/L) , year need 180/(0.05 × 10-6)/1000=360 10 thousand tons of clean water are attenuant; If reach I grade level (Cr6 <0.01mg/L) , criterion year need dilute of 18 million tons of clean water. Among them, every kilogram content is as high as the Cr6 with incomplete highest brick 2577 milligram, more need clean water 10 tons of dilute, ability makes its reach I grade level. Countrywide cement rotary kiln produces per year a quantity with 600 million tons plan, annual the incomplete brick of eduction makes an appointment with 60 thousand tons, discharge Cr6 every year to amount to 60 tons to the environment. To make environmental water reachs IV grade level (Cr6 <0.05mg/L) , year need dilute of 2 billion tons of clean water; If reach I grade level (Cr6 <0.01mg/L) , year need dilute of 6 billion tons of clean water.
Previous12 3 Next