添加造纸白泥对猪场废水厌氧消化液中氮磷回收的影响

以造纸废弃物白泥作为pH调节剂,利用MAP沉淀法回收厌氧消化液中的氮磷,并采用曝气的方式提高消化液pH值和造纸白泥的溶解性,研究了造纸白泥的添加量和曝气时间对厌氧消化液中氮、磷回收效果的影响,并考察了曝气过程中pH、COD、PO34--P、NH3-N、Mg2＋、Ca2＋的变化规律。结果表明造纸白泥的添加量为8g.L-1,曝气时间为120min时,PO34--P和NH3-N的回收率分别达到98和59,出水的PO34--P和NH3-N浓度分别为0.98mg.L-1和60.66mg.L-1,均达到了《畜禽养殖业污染物排放标准》（GB18596—2001）的要求,同时,COD的去除率为45;如果仅用曝气方式处理,120min后PO34--P和NH3-N的回收率仅分别为66和41,均未达到排放标准要求。可见,与仅用曝气方式处理相比,添加造纸白泥协同曝气对厌氧消化液中氮磷的回收有明显的效果

添加晶种对沼气发酵液磷回收的影响研究

以畜禽养殖废水经厌氧消化处理后的沼气发酵液为研究对象,采用曝气吹脱调节pH的处理方式。晶种采用海泡石粉、沸石粉和凹凸棒石粉3种天然矿物材料。考察了不同pH条件、晶种添加量和不同初始磷负荷对磷回收的影响,并利用扫描电镜-能谱分析仪（SEM-EDX）对产物进行了表征分析。结果表明：3种晶种材料中,凹凸棒石粉对磷回收的促进效果最好。在pH从7.5到8.5之间海泡石粉、沸石粉和凹凸棒石粉均可将Rp（t）提高10%以上,8.5到9.5之间,添加海泡石粉和沸石粉对Rp（t）的提升幅度降低,添加凹凸棒石粉可以达到14%左右的提升幅度。海泡石粉和沸石粉添加量增大后Rp（t）有小幅的提升,但变化不规律,凹凸棒石粉的最佳添加量为0.92 g/L。初始PO43--P为90 mg/L时凹凸棒石粉对磷回收有最好的促进效果。添加凹凸棒石粉的产物在SEM图片上可看到明显有晶体覆盖,EDX图上出现了明显的强度较大的P组分峰,从微观的角度证实了添加凹凸棒石粉的促进作用

Measurement of integrated luminosity of data collected at 3.773 GeV by BESIII from 2021 to 2024

We present a measurement of the integrated luminosity e+e- of collision data collected by the BESIII detector at the BEPCII collider at a center-of-mass energy of Ecm = 3.773 GeV. The integrated luminosities of the datasets taken from December 2021 to June 2022, from November 2022 to June 2023, and from October 2023 to February 2024 were determined to be 4.995±0.019 fb-1, 8.157±0.031 fb-1, and 4.191±0.016 fb-1, respectively, by analyzing large angle Bhabha scattering events. The uncertainties are dominated by systematic effects, and the statistical uncertainties are negligible. Our results provide essential input for future analyses and precision measurements

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^