Study On Properties Of Subgrade Material For Drying Slurry By Drilling

With the increasing demand for energy industry of oil, the environment problems of the waste produced by the oil production are gradually obvious. To deal with the waste drilling mud, the method of drilling with the rule is used. Through adding the prepared curing agent into a mud pool, it directly makes the drilling mud on the scene treated by harmless solidification. Although this method is simple and practicable, it also exists four defects. First, it has the matter of high land acquisition costs and the waste of land resources. Second, it is easy to cause secondary pollution. Then, this original process is not conductive to environmental protection. Finally, it can not be reused, and up to the requirements of energy conservation and environment protection.From the perspective of recycling to meet the emission of pollutants and basic properties of subgrade materials, this paper regards the waste drilling mud modified and solidified as subgrade materials to pave simple subgrade nearby. First of all, the waste drilling mud is solidified through the traditional process. Then, combined with the basic properties of subgrade materials and the state of solidified drilling mud, it should be made improved solidification treatment to satisfy the requirements of various indexes. The main work and achievements of this paper are as follows:(1) The composition, properties and classification of the waste drilling mud and the basic performance requirements of subgrade materials are expounded in detail.(2) Through the indoor contrast experimental study, it preferred out the gel breaker and curing agent of the waste drilling. The composition and mixed ratio of gel breaker is1.5%of aluminum sulfate and0.5%of PAC; that of curing agent is40%of fly ash,5%of lime,10%of gyp,5%of cement and10%of loess.(3) Through the analysis of the state of solidified drilling and combined with the basic properties of subgrade materials, this paper puts forwards the improvement programs:the gel breaker is unchanged, and the curing agent is converted into the lime and fly ash.(4) By means of analysis and research, this paper selects the curing agent as the secondary ash curing agent of the lime and fly ash. The mixed ratio of them is1:3. Then combined with environmental indicators and the basic properties requirements of subgrade materials, the waste drilling mud is improved solidification with different mixed ratio(30%,40%,50%,60%,70%) of secondary ash curing agent. Via them, the optimal mixed ratio of secondary ash is60%. Meanwhile, in the proportion of it, each index can meet the requirements of the specification, which COD is80mg/L, chroma is35, the content of the oil is3.5mg/L, liquid limit is45.4%, plastic limit is36.3%, plasticity index is9.1, CBR is19.4and unconfined compressive strength is1.55MPa.(5) Combined with the improved solidification program, this paper puts forward construction scheme of the scene, and makes economic benefit evaluation through the analysis and calculation of the cost of the raw materials. It can be found that the improved solidification has a certain economic value, and provides the certain reference value for the application of actual engineering.