Papadopoulos A, Parisopoulos G, Papadopoulos F, Karteris A
NAGREF/Soil Science Institute, 570 01 Thermi, Thessaloniki, Greece.
Water Res. 2003 Feb;37(3):634-44. doi: 10.1016/s0043-1354(02)00307-x.
The main objective of this study was to observe the sludge accumulation pattern of an experimental, covered, anaerobic pond treating municipal wastewater under Mediterranean climatic conditions throughout a 2-year operational period (1999-2000) in order to form a seasonal sludge accumulation model which may be used to predict the required desludging time, not only of the particular anaerobic pond used in the study, but also for other types of anaerobic ponds and operational situations. The 4-m deep pond was supplied with pre-screened, untreated wastewater from the nearby treatment plant of Thessaloniki, Greece, initially at a flow rate of 120m3/day and later at a flow rate of 150m3/day. The influent characteristics were BOD5 441 mg O2/L, COD 942 mg O2/L and suspended solids (SS) 574 mg/L. BOD5, COD, and SS concentrations of the pond effluent were reduced by 50%, 53%, and 64%, respectively, in comparison with those of the influent. During the operational period, three distinctly different zones were seen to form within the anaerobic pond: The first zone, which formed at the bottom of the pond, consisted of inert, high-density sludge. The second zone, which formed above this, contained a high concentration of volatile (easily biodegradable) sludge. The third upper zone (supernatant), was a liquid layer low in suspended solids. The accumulation of sludge in the pond followed an annual sinusoidal pattern with high values during winter and low ones during summer due to the increased digestion rate. The maximum high-density sludge height observed was 0.7m, or 2% (14 m3) of the total pond volume. The maximum volatile sludge accumulation reached 3.1 m, or 53% (300 m3) of the pond volume. A seasonal sludge accumulation model, based on the sludge inflow and seasonal digestion rates, was used to simulate the annual fluctuation in accumulation rate for the local (Mediterranean type) climatic conditions. Monthly values of accumulation (or digestion) rate of sludge (K(AS)) were experimentally estimated at specific mean monthly air temperatures and approximated by a regression second degree polynomial equation to be used with the model. The predicted desludging interval for our experimental pond was 3 years.
本研究的主要目的是观察一个用于处理城市污水的实验性覆盖厌氧塘在两年运营期（1999 - 2000年）内，于地中海气候条件下的污泥积累模式，以形成一个季节性污泥积累模型，该模型不仅可用于预测本研究中使用的特定厌氧塘所需的清淤时间，还可用于其他类型的厌氧塘及运营情况。这个4米深的池塘接收来自希腊塞萨洛尼基附近污水处理厂经预筛分的未处理污水，最初流量为120立方米/天，后来为150立方米/天。进水特征为五日生化需氧量（BOD5）441毫克O2/升、化学需氧量（COD）942毫克O2/升和悬浮固体（SS）574毫克/升。与进水相比，池塘出水的BOD5、COD和SS浓度分别降低了50%、53%和64%。在运营期间，厌氧塘内形成了三个明显不同的区域：第一个区域在池塘底部形成，由惰性的高密度污泥组成。在其上方形成的第二个区域含有高浓度的挥发性（易生物降解）污泥。第三个上部区域（上清液）是悬浮固体含量低的液体层。由于消化速率增加，池塘内污泥的积累遵循年度正弦模式，冬季值高，夏季值低。观察到的最大高密度污泥高度为0.7米，占池塘总体积的2%（14立方米）。最大挥发性污泥积累量达到3.1米，占池塘体积的53%（300立方米）。基于污泥流入量和季节性消化速率的季节性污泥积累模型，用于模拟当地（地中海型）气候条件下积累速率的年度波动。在特定的月平均气温下，通过实验估计污泥积累（或消化）速率（K(AS)）的月度值，并通过二次回归多项式方程进行近似，以便与该模型一起使用。我们实验池塘的预测清淤间隔为3年。
