论文部分内容阅读
以锯木灰、谷壳灰、玉米灰、水稻灰4种灰渣为研究对象,采用平衡法研究生物质灰渣对磷的吸附与解析特性。结果表明,灰渣对磷的吸附量随着加入液磷浓度的增加而增加,但增加速率逐渐减缓。与其他生物质灰渣相比,锯木灰在不同浓度下对磷的吸附量和吸附率均较高,吸附量在0.98~11.21g/kg范围内,吸附率均在55%以上,最高可达97.72%。然而,随着加入液磷浓度的增加,吸附态磷解吸率逐渐减小,解吸量逐渐增加,在加入的磷浓度为2 000mg/L时,4种灰渣的解吸量都达到最大值,为最小解吸量的3.5~6.4倍。不同种类的灰渣由于化学组成不同吸附与解吸能力也不同,不同磷浓度对水稻灰、谷壳灰、玉米灰的解吸率影响最大,最高解吸率和最低解吸率差值分别为56.53%,53.67%,44.53%;对锯木灰的影响相对较小,差值仅有12.53%。用Langmuir方程拟合4种灰渣的等温吸附曲线和等温解吸曲线,得到的相关系数都达到显著水平。灰渣对磷的吸附和解吸的动力学特征存在一定的相似性,一般吸附量大的灰渣对磷的解吸量也大;吸附能力强的灰渣对磷的解吸能力也强。锯木灰对磷的吸附解吸能力强于其他3种灰渣。由于灰渣对磷的吸附和解吸能力对土壤中磷的生物有效性有重要影响,因此在选择灰渣种类时需适时适量。
Four kinds of ash, sawdust, chaff, corn ash and rice ash were taken as research objects. The balance method was used to study the adsorption and analysis of phosphorus on biomass ash. The results showed that the amount of phosphorus adsorbed by ash increased with the increase of phosphorus concentration, but the rate of increase gradually decreased. Compared with other biomass ash, sawdust at different concentrations of phosphorus adsorption and adsorption rate were high, the adsorption capacity in the range of 0.98 ~ 11.21g / kg, the adsorption rate was above 55%, up to 97.72%. However, with the increase of phosphorus concentration, the desorption rate of adsorbed phosphorus gradually decreased and the amount of desorption increased gradually. When the added phosphorus concentration was 2 000 mg / L, the desorption amounts of the four kinds of ash reached the maximum The minimum desorption amount of 3.5 to 6.4 times. Different types of ash have different adsorption and desorption capacities due to different chemical compositions. Different phosphorus concentrations have the greatest effect on the desorption rate of rice ash, husk ash and corn ash with the maximum desorption rate and minimum desorption rate being 56.53% and 53.67, respectively %, 44.53%; the impact of sawdust is relatively small, the difference is only 12.53%. Using Langmuir equation to fit the isothermal adsorption curves and isothermal desorption curves of four kinds of ash, the correlation coefficients reached significant levels. The kinetic characteristics of ash adsorption and desorption have some similarities. The desorption amount of phosphorus by the ash with large adsorption capacity is also large. The desorption capacity of ash with strong adsorption capacity is also strong. Saw ash adsorption and desorption of phosphorus stronger than the other three kinds of ash. As ash adsorption and desorption of phosphorus on soil bioavailability of phosphorus has a significant impact, it is necessary to select the appropriate type of ash when appropriate.