脱硫石膏标准.doc

脱硫石膏标准标准编制发起和主要完成单位是北京建筑材料科学研究总院，目前提出的初步方案大概如下：1.按不同烟气脱硫石膏品质和用途，对产品要求进行分级：一级和二级2.游离水：小于 10%和小于 15%两个等级要求3.二水硫酸钙：二水硫酸钙的含量作为脱硫石膏的主要分级指标，估计是 80%和 90%两档4.可溶于水的镁盐和钠盐：在标准将分级进行限制5.氯化物：需在进行不同地区脱硫石膏验证实验后，结合欧洲协会标准（〈0.01%）进行确定6.半水亚硫酸钙：欧洲协会标准是小于 0.5%7.PH 值：应呈基本中性，5-98.颜色：按使用要求进行分级9.气味：建议采用这项指标10.平均颗粒尺寸：在标准中将进行限定（欧洲协会标准是 32 微米以上大于 60%）11.可燃有机物成分：纳入否需试验验证后确定12.Al2O3和 SiO2:纳入否需试验验证后确定13.Fe2O3:纳入否需试验验证后确定14.放射性元素：应满足国家标准 GB6566-2001《建筑材料放射性核素限量》标准要求15.毒性：根据 Bekert,J;Einbrodt.H;Fischer.M:天然石膏和烟气脱硫石膏的对比来测定有毒物质[1990]作为试验方法。

Quality parameters Expressed as : Unit Quality CriteriaFree moisture H2O % by weight 95 (1)Magnesium salts, water soluble MgO % by weight < 0.10Sodium salts, water soluble Na2O % by weight < 0.06Chloride Cl % by weight < 0.01Calcium sulphite hemihydrate CaSO3 x 1/2 H2O % by weight < 0.50pH 5 - 9Colour % white (2)Odour neutralToxicity non-toxic(1) The reduction of the calcium sulphate dihydrate content by inert constituents is not detrimental to the different areas of application.(2) Different colour values may apply depending on the use of the FGD gypsum and the final products.ANALYSIS METHODS FOR THE DETERMINATION OF THE QUALITY PARAMETERSOF THE PRODUCT FGD GYPSUMFGD gypsum quality parameters are determined in accordance with VGB Instruction Sheet “Analysis of FGDP Gypsum”(VGB-M 701e, 1991). This instruction sheet is available from VGB PowerTech e.V. at:http://www.vgb.org/shop/product_info.php/products_id/159.Any analysis of water-soluble salts of sodium, magnesium, potassium and manganese (Na2O, MgO, K2O and MnO) is to be carried out with reference to the analytical methods for water-soluble magnesium salts decomposed at boiling temperature(stock solution A2 according to VGB instruction sheet VGB-M 701e Part I, 1991).Toxic substances are determined in accordance with Beckert, J.; Einbrodt, H-J.; Fischer, M.: Comparison of NaturalGypsum and FGD Gypsum (1990) (Source: Bundesverband der Gipsindustrie e.V., Darmstadt and VGB PowerTech e.V.,Essen).It is also possible to use other analysis methods for the determination of the quality parameters in the product FGD gypsum.However, it must be verified that they produce the same results as the methods listed here or that the results differ only with a constant correlation factor.COMMENTS ON THE PRODUCTION OF GYPSUM-BASED PRODUCTSFGD gypsum quality shall be such that it can be used for the production of gypsum-based products which are equivalent to those made from natural gypsum.In principle, this is the case when the quality criteria mentioned above are complied with. FGD gypsum is therefore suitable, without any additional requirements, for the vast majority of the common uses of gypsum.However, there may be variations in some of the quality parameters mentioned in this document, if it can be ensured, in specific cases, that the gypsum blend intended for the manufacturing of the product in the gypsum factory complies overall with the requirements.Relevant quality parameters and analysis methods will be specified in the conditions of the contracts for the supply and reception of FGD gypsum.INDICATIONS FOR THE USE OF FGD GYPSUM IN SPECIAL AREAS OF APPLICATIONWhen FGD gypsum is used in the specific areas of applications listed below, the following guidelines need to be followed to ensure the acceptable quality of gypsum products.These guidelines should not be considered as obligatory for achieving what is required but as recommendations based on long-term knowledge and experience.1. Efflorescence and discolourationsFor the unrestricted production of gypsum-based products sensitive to efflorescence, a content of water-soluble saltsof magnesium (MgO), sodium (Na2O) and potassium (K2O) of below 0.02 % is recommended.Verification of the content of carbon, soot, fly ash as well as water-soluble salts of iron (Fe2O3) and manganese (MnO)is recommended in order to avoid various discolourations on visible surfaces.2. Particle size / Crystal habit (particle size distribution)It is recommended to specify the particle size (for example, average diameter D50) and crystal habit (visual test by microscope) in the conditions for the supply and reception contracts for FGD gypsum.3. Gypsum BlocksWhen using FGD gypsum for the production of gypsum blocks in accordance with EN 13859, it can be used without any additional measures if the value of water-soluble MgO is below 0.02 %.4. BindersThe content of carbonate shall be tested for the use of FGD gypsum for the production of binders based on alpha calcium sulfate hemihydrate or anhydrite. FGD gypsum with 。