| As one of the three basic materials of builing industry,cement has a large production and usage in our country.However,cement industry needs to consume a large amounts of resources and energy.When production of one ton of cement clinker,will consume about 1.1 tons of limestone,0.25 tons of clay and 0.11 tons of coal.At the same time,cement production will produce large amount of gas such as CO2?CO?NOx and SO2.These gases will cause the greenhouse effect and pollute the ecological environment.So it is imperative to find new materials and new techniques to reduce resource consumption and environment pollution of the cement industry.On the other hand,rice husk is the main by-product after rice processing.There is a lot of rice husk in our country every year.A few of these rice husk used in daily life make a fire to cook.Most piled up or burned as "junk",had a certain influence on land and ecological environment.People are focus on the potential value of the rice husk.Research and exploitation the comprehensive utilization of rice husk.But relative to the number of rice husk,the utilization of rice husk is still low.Rice husk contains a certain amount of silicon.Silicon is the basic material in the manufacture of the Portland cement.Therefore put forward using rice husk alternative natural clay as raw materials to produce the rice husk cement.Thus to minimize the use of mineral resources,provide some heat and protecting the environment.At present the study of rice husk is mainly concentrated in rice husk cement concrete and volcanic activity of rice husk ash.However rice husk as a raw material to produce the rice husk cement is rare reported.In recent years,precalcining technology is used for cement production.But it cannot be simulated under laboratory conditions.So in this paper,the way of calcining cement were studied first.Through contrast the compressive strength of cement slurry by heating up from room temperature to specified temperature and from 950? to specified temperature.Compared with eating from room temperature,heating from 950 ? the strength of cement for 3 days increased by 50%,28 days increased by 42%.Determine from 950 ? heat to the set temperature for cement calcinations in subsequent tests.Paper studied the different rice husk content,calcinations temperature,KH affect the performance of rice husk cement after determined how to calcinate cement in the laboratory.Compared the compressive strength of cement which content of rice husk were to 0,2%,3%,5%,10%,KH=0.90,SM=2,IM=1.2,calcination temperature at 1350 ?.The results showed that when rice husk content was not too much,had a little influence on strength of rice husk cement.When rice husk content more than 3%,the strength of the cement began to decline.Set 1200 ?,1250 ?,1300 ?,1350 ? and 1400 ?,these five temperature in the study of calcination temperature,KH=0.90,SM=2,IM=1.2,rice husk content is 3%.Below 1300?,the rice husk cement clinker burning is not successful by the experimental results.As temperature rise,the strength of rice husk cement is increasing.In the experiment about the KH influenced on the rice husk cement,set the KH is 0,86,0.88,0.90,0.92 and 0.94.Then set SM=2,IM=1.2 and rice husk content is 3%,Found that with the increase of KH,the strength of rice husk increased for 3 days,decreased for 28 days and the decreased of the trend is greater than the contrast.So can say the increase of KH is not good for the performance of the cement.This paper also studied the strength of rice husk ash lime cement without clinker and hydrated lime cement without clinker of which rice husk ash calcinations in 500?,600?,700?,800?,900? and burning in the air directly.The results showed that calcination in 700 ? would get high strength.Meantime the strength of rice husk ash hydrated lime cement without clinker is slightly higher than rice husk ash lime cement without clinker. |
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