| Barium residue is the industrial waste which is generated by producing barium carbonate by barite, and is solid residue which is remained by high temperature calcination, cooling and hot water taking of raw material barite and cinder. According to the investigation, for every ton of barium salts produces 0.8-1 tons of barium residue.Barium slag containing acid soluble barium, water soluble barium and Portland clinker, the barium slag treatment still to pile up, causing tremendous waste of resources and environmental pollution. According to the literature, the main utilization ways of barium residue study are producing barium salt, waste water treatment and production of building material bricks. However, because all of the direct use, but not to carry out a systematic study, resulting in a useful component of barium slag not be fully utilized. In this paper, studying the physicochemical properties and the regularity dissolving by barium slag ions, and resource utilization, for the utilization of barium residue theoretical foundation.In this paper, gravimetric method, atomic absorption spectrometry and ICP-MS method were used to analyze the composition of barium residue, as a result: barium sulfate 14.59%, barium silicate 17.32%, barium carbonate 30.92%, water-soluble barium 0.33%, silica 24.33%, strontium sulfate 0.024%, strontium carbonate 0.13%, ferrous oxide 2.71%, aluminum oxide 6.83%, calcium oxide 0.44%, there are traces of trace elements and rare earth elements.It was obtained that BaSO4、BaSiO3 and SiO2 were primary ingredients of barium residue by XRD for barium residue phase and components analysis, and barium sulfate in the presence of two phases. Using SEM-EDS for morphology and composition analysis of barium residue, obtained that there are two different morphologies structure of barium residue, one is layered structure of un-decomposed barite, another is the melt structure of porous after decomposition of barite.In this paper, barium residue solubility properties were researched by hydrochloric acid extraction method, the effects of the concentration of hydrochloric acid, liquid to solid ratio, reaction temperature and reaction time on the solubility properties of barium residue were studied, as the result, barium residue dissolved excellent technological conditions were obtained: the concentration of hydrochloric acid 3.0mol/L, liquid to solid ratio7:1, reaction temperature 70℃, reaction time 6h; analyzing phases and components of different leaching time residue By XRD, as the result: the ions in the barium slag dissolution order with temperature and time changes, is not consistent with the results of thermodynamic calculation.In this thesis, using wash residue- leaching-purify combining process to produce barium chloride.At first,mixture of ethanol and hydrochloric acid system was used to wash barium residue, the effect of concentration of hydrochloric acid, liquid to solid ratio on leaching rate of each ion of wash-residue was investigated, suitable wash residue conditions were obtained: the concentration of hydrochloric acid 1mol/L, liquid-solid ratio1,the dissolution rate of Ba2+ was 7.45%. Leaching barium ion of residue of wash residue by hydrochloric acid, investigating the impact of concentration of hydrochloric acid, liquid-solid ratio, reaction temperature, reaction time and stirring speed on the barium ion leaching rate, to optimize the process conditions: hydrochloric acid concentration 2 mol/L, liquid-solid ratio 3:1, reaction temperature 60℃, reaction time is 4h, stirring speed 400 r/min, the dissolution rate of Ba2+ was 68.72%. Compared with traditional one time acid leaching process, this process reduced acid consumption in the process of 50%, and the content of barium in the filtrate increased from 92.76% to 95.61%.The above leaching filtrate for preparation of barium chloride,obtaining that barium chloride purity was 99.71% for p H = 3 by investigating impact of pH value on barium product purity, which lines with the "GB / T 1617-2014" purity of barium chloride within category Ⅰproduct.This thesis, recovering strontium ion by removing calcium, iron, aluminum and barium ions in filtrate of washed barium residue, the influence of p H an d temperature on calcium, iron and aluminum ions’ precipitation rate was researched that calcium, iron, aluminum ion precipitation rate were 91.6%, 95.2% a nd 91.7% respectively at p H = 12, temperature 80 ℃. The impact of dosage o f Na2SO4, temperature and stirring time on barium ion precipitation rate was st udied that barium ion precipitation rate of 97.3% when 0.1 mol/L sodium sulfa te 70 ml, temperature 50℃, mixing time 30 min. Crystallizing filtrate after re moving impurity, keeping crystal temperature at 200 ℃ for 2h to gain strontiu m chloride product, the product’s purity can reach 96.2%, recovery rate of stro ntium ions in barium residue was 75.67%.This paper, the rest residue which was left from producing barium chloride was used to produce non load-bearing brick, based on the raw material ratio in the production of non load-bearing brick using barium residue, optimizing mixture ratio by orthogonal experiment, it is concluded that the optimal ratio of material: barium residue 45%, fly ash 8%, cement 6%, slag 20%, lime 15%, gypsum 3%, expanded perlite 3%. Non load-bearing brick which produced at the optimal proportioning, the brick compressive strength is 25.4 MPa, flexural strength is 5.3 MPa, the density of 1.33 g/cm3, bibulous rate is 10.58%.Its strength up to “GB11945-1999” MU25 compressive and flexural strength. Increased 13 MPa compared with the original barium residue brick compressive strength,the flexural strength increased by 2MPa, the density also decreased by 0.4g/cm3. |
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