Determination of Limits to Biological Loading Rate in Column Experiments with Florida Sandy Soils

Organic loading rate (OLR), Hydraulic Retention Time (HRT) and up flow velocity are important parameters significantly affecting microbial ecology and characteristics of anaerobic reactors. In this study, Performance of an anaerobic hybrid reactor (UASB/Filter) at mesophilic condition was evaluated in a 15.4 L reactor receiving petrochemical wastewater. The temperature of influent was adjusted by an inline heat exchanger at around 35 ˚C. The reactor was seeded with flocculent sludge from a UASB plant treating dairy wastewater. The sludge was acclimatized to petrochemical wastewater in twostage operation. After 39 weeks, a COD reduction of 70.3% was obtained at OLR=2.0 kg m-3 d-1 and HRT=18 h. Under steady state conditions, experiments were conducted at OLRs of between 0.5 and 24 kg TCOD m-3 d-1 , hydraulic retention times (HRT) of 4-48 h and up flow velocities 0.021-0.25 m h-1. Removal efficiencies in the range of 42-86% were achieved at feed TCOD concentrations of 1000- 4000 mg L-1 . The biogas production data used for determination of biogas production kinetics. The values of Gmax and GB estimated as 11.173 LL-1d -1 and 85.83 g L-1d -1 , respectively.

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Preparation of a New Cd(II)-Imprinted Polymer and Its Application to Preconcentration and Determination of Cd(II) Ion from Aqueous Solution by SPE-FAAS

Indonesian Journal of Chemistry ◽

10.22146/ijc.27703 ◽

2019 ◽

Vol 19 (1) ◽

pp. 97

Author(s):

Teguh Wirawan ◽

Ganden Supriyanto ◽

Agoes Soegianto

Keyword(s):

Nitric Acid ◽

Loading Rate ◽

Solid Phase ◽

Absorption Spectrometry ◽

Imprinted Polymer ◽

Flame Atomic Absorption ◽

Ion Imprinted ◽

Ft Ir ◽

Polymerization Method

A novel ion Imprinted polymer (IIP) material with 8-hydroxyquinoline (8HQ) (the complexing ligands), methacrylic acid (MAA) (the monomers), ethylene glycol dimethacrylate (EGDMA) (the crosslinker agent), benzoyl peroxide (the initiator), and ethanol-acetonitrile (2:1) (the porogen) as adsorbent for the determination of cadmium by solid phase extraction–flame atomic absorption spectrometry (SPE-FAAS) has been synthesized. Synthesis of IIP was done by precipitation polymerization method. The imprinted Cd(II) ions were removed by leaching method using 1 mol L-1 nitric acid. The IIP was characterized by fourier transform infra-red (FT-IR) spectroscopy and scanning electron microscopy (SEM) to ensure successful synthesis of IIP. The experimental parameters for SPE extraction, such as pH of the sample, loading rate, and elution rate, have been optimized. The optimum pH for quantitative Cd(II) retention was 6, and the elution was completed with 2 mL of 1.0 mol L-1 nitric acid. The optimum loading rate was 0.5 mL min-1. Under optimum conditions, the proposed method with theoretical enrichment factor 50 times has a detection limit of 0.5 µg L-1 and the recovery of 97.75%.

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Water Saturated Column Experiments for the Determination of Mobilizable Inorganic Pollutants from Loose Material

Vom Wasser ◽

10.1002/3527600892.ch3 ◽

2003 ◽

pp. 49-60 ◽

Cited By ~ 2

Author(s):

Markus Delay ◽

Daniel Schmitt ◽

Fritz Hartmann Frimmel

Keyword(s):

Loose Material ◽

Column Experiments ◽

Inorganic Pollutants ◽

Water Saturated

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Determination of the fracture toughness of a saturated soft rock

Canadian Geotechnical Journal ◽

10.1139/t90-038 ◽

1990 ◽

Vol 27 (3) ◽

pp. 276-284 ◽

Cited By ~ 26

Author(s):

C. M. Haberfield ◽

I. W. Johnston

Keyword(s):

Fracture Toughness ◽

Plane Strain ◽

Loading Rate ◽

Soft Rock ◽

Plane Strain Fracture Toughness ◽

Hard Rocks ◽

Strain Fracture ◽

Reasonable Range ◽

Insight Into

Although the literature provides a reasonable range of information concerning the fracture toughness of relatively hard rocks, there is virtually no data for saturated soft rocks of uniaxial compressive strengths less than about 10 MPa. To gain some insight into the plane strain fracture toughness of such a soft rock for use in the numerical modelling of crack propagation during pressuremeter testing, a large number of laboratory tests were conducted. The material used in these tests was a synthetic soft rock that modelled soft mudstone rocks reasonably accurately. This paper describes the test techniques adopted and the results obtained. The variation of fracture toughness with loading rate and with size and shape of the test specimens is presented and discussed. On the basis of these results, guidelines are suggested for the determination of plane strain fracture toughness of a soft rock. Key words: fracture mechanics, fracture toughness, laboratory testing, soft rock, weak rock.

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