STUDY ON MAXIMUM SPECIFIC SLUDGE ACTIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

The maximum specific sludge activity of granular sludge from large scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results.

Re-Testing in Batch Testing Model Based on Quality Control Process for Proportion Estimation

The quality of products manufactured or procured by organizations is an important aspect of their survival in the global market. The quality control processes put in place by organizations can be resource-intensive but substantial savings can be realized by using acceptance sampling in conjunction with batch testing. This paper considers the batch testing model based on the quality control process where batches that test positive are re-tested. The results show that re-testing greatly improves the efficiency over one stage batch testing based on quality control. This is observed using Asymptotic Relative Efficiency (ARE), where for values of p computed ARE > 1 implying that our estimator has a smaller variance than the one-stage batch testing. Also, it was found that the model is more efficient than the classical two-stage batch testing for relatively high values of proportion.

Anaerobic Co-Digestion of Fish Processing Waste with Cow Manure and Waste of Market (Rests of Fruits and Vegetables): A Lab Scale Batch Test

The aim of this work was to use fish processing waste (FW) as main substrate for anaerobic digestion. To enhance the biogas production of FW, co-digestion was done with two other substrates: cow dung (CD) and waste of market (MW). Batch test was carried out in an 1 L glass digester in a temperature controlled chamber at 38°C. The following mixtures were carried out: FW with CD respectively at different ratios 100:0% (A), 80:20% (B) and 60:40% (C);FW with MW at the following ratio 80:20% (D);FW with CD and MW respectively at these ratios 80:10:10% (F) and 60:20:20% (G). The biogas produced was measured using a milligas counter® and the volume of gas was recorded. The gas composition was determined using gas chromatography. With a pH stable for raw substrates and mixtures, TS and VS (%TS) contents for FW were respectively 31.01% and 91.55%. Between 3 to 13 days of experimentation, the highest flow rate was observed. The percentage of methane was more important for mixtures B and D, 61% and 59% respectively. pH and VOA/TIC were stable at the end of the batch test for all mixtures, meaning that the organic matter was already well digested. The highest values of Volatile Solid Removal (VSR) were found for mixtures C, D, F and G. Therefore, the promising mixtures for next experimentations in large scale are B and D.

Separation of macro amounts of tungsten and molybdenum by ion exchange with D309 resin

Based on the difference in tendency to polymerize between tungsten and molybdenum, a new method using D309 resin was propounded. The batch tests indicate that the optimum pH value and contact time for the separation are 7.0 and 4 h respectively, the maxium separation factor of W and Mo is 9.29. And the experimental resules show that isothermal absorbing tungsten and molybdenum belongs to Langmuir model and Freundlich model respectively, and the absorbing kinetics for tungsten is controlled by intra-particle diffusion. With a solution containing 70 g/L WO3 and 28.97 g/L Mo, the effluent with a mass ratio of Mo to WO3 of 76 and the eluate with a mass ratio of WO3 to Mo of 53.33 are obtained after column test.

Phosphorus removal by adsorbent based on poly-aluminum chloride sludge

Phosphorus adsorption tests were carried out using poly-aluminum chloride sludge(PACS),which was collected from a water treatment plant in Nanjing.The amount of phosphorus adsorbed by PACS increased quickly within the first hour and reached equilibrium after about 48 h.The adsorption behavior of PACS for phosphorus is consistent with the Langmuir adsorption isotherm equation(R2>0.99)and parallel first-order kinetic equation(R2>0.98).With the increase of the PACS concentration,the adsorption capacity of PACS for phosphorus decreased,and the removal rate increased.The results of batch tests showed that the adsorption capacities of PACS for phosphorus ranged from 1.64 to 1.13 mg/g when the pH value varied from 4 to 10.However,the adsorption capacity of PACS was not evidently influenced by temperature.In comparison with the ion exchange resin,the adsorption capacity of PACS was barely inhibited by competitive ions,such as SO2
4,NO
3,and Cl
.The PACS surface after adsorption became smooth,and the vibration peaks of AleO and AleOH shifted.Both HCl and NaOH have a strong desorption effect on PACS after adsorption saturation,and with higher concentrations of HCl and NaOH,the desorption effect was stronger.Results of column adsorption experiments showed that with lower phosphorus and hydraulic loads,the adsorption column took longer to reach saturation.This indicated that PACS could be used as an efficient material for removal of phosphorus from water.This study provides a new treatment method with PACS.

Evaluation of Filter Material for Treatment of Different Types of Wastewater

This paper presents an evaluation of the suitability of a mixed absorbent based on peat and carbon-containing ash for treatment of wastewaters, such as wastewater from professional car washes, landfill leachate and stormwater. This mixture is very attractive, since it is a low-cost material which has a capability to simultaneously remove inorganic as well as organic pollutants. Since any filter material eventually needs to be replaced either due to saturation of pollutants or reduced infiltration capacity, it is important that the residual can be handled at low cost and that the environment will be not impaired. The tested mixture, used in filter beds, showed low leaching values and high simultaneous removal efficiency of metals as Cu, Cd and Pb, non-polar organic compounds such as PCBs. Polar organic compounds as phenols were also efficiently removed by microbial and/or chemical degradation in the studied treatment plants with the filter bed acted as a biofilter. Filter material used for three years in a full-scale plant for leachate treatment and four years in treatment plants for wastewater from car washes, had sufficiently high energy content indicating that energy recovery is a good alternative for handling after its usage. Results show that the presented filter material is excellent for both small scale applications (e.g. treatment systems for car wash wastewater with capacity between 250 - 3000 m3 per year) as well as large-scale applications (e.g. filter systems for landfill leachates with capacity above 30,000 m3 per year).

Separation of indium(Ⅲ), gallium(Ⅲ), and zinc(Ⅱ) with Levextrel resin containing di(2-ethylhexyl) phosphoric acid (CL-P204): Part Ⅱ. Mechanism and kinetics of adsorbing indium(Ⅲ)

The mechanism of adsorbing indium(Ⅲ) from sulfate solutions with CL-P204Levextrel resin containing di(-2-ethylhexyl) phosphoric acid was examined by batch operation andinfrared spectra. The results showed that the P204 adsorbed on the resin behaved in the similar wayto solvent extraction except that it was as a monomer in resin adsorbing but in dimeric form insolvent extraction. Three factors including temperature, indium(Ⅲ) concentration of solution, andthe size of resin particles which influence the In^(3+)/H^+ exchange on CL-P204 Levextrel resin wereinvestigated by the modified limited batch technique in order to determine the kinetics ofIn^(3+)/H^+ exchange. It was found that the rate of ion exchange increased with the temperature andthe concentration of solution increasing and with the size of the resin particles decreasing.According to the expression developed by Boyd et al., the controlling factor of In^(3+)/H^+ exchangeon CL-P204 Levextrel resin was the diffusion through the resin particles. The effective diffusioncoefficient, activation energy, and entropy of activation in the particle-diffusion were determinedas 1.57 x 10^(-10) m^2/s, 11.9 kJ/mol, -84.1 J/(mol·K), respectively.

Process for the Biological Removal of Fe (II) from Reconstituted Waters on a Support of Filter Material with Coated Jujube Seeds

Three beakers for removing Fe (II) in reconstituted water (doped with FeSO4) were built and tested. Given the set operating conditions ([O2] > 4 mg·L-1, Patm = 1.013 bar, T = 25°C ± 1°C and [Fe2+]0 = 0.5 to 2 mg·L-1), removal of iron was caused by biological and possibly physical and chemical oxidation because there is a quantity of free oxygen in the medium. The extent of each type of oxidation has not been evaluated as it specifically studies the biological degradation of iron in these beaker tests by setting the operating conditions (pH > 6.5, dissolved oxygen from 0 to 8 mg·L-1, Redox Potential from 100 to 400 mV). The experimental studies focused particularly on the measurements of maximum wavelength, conversion efficiencies from Fe (II) to Fe (III), the effect of the Fe (II) concentration, the influence of pH, the action of the temperature of the prepared solutions and the effect of O2 concentration under specified operating conditions. It noticed precipitated amounts of iron deposited at the bottom of the beakers. Thus, the low concentrations of Fe (II) detected in the influent after the biological oxidation operation could be attributed to microorganisms that consume iron as a substrate.

Determination and evaluation of biogas and methane productions of vegetable and fruit wastes with Hohenheim Batch Test method

Nowadays,biogas technology applications are gradually increasing worldwide due to the economic and environmental benefits.Many researches and studies related to the determination of the biogas potential of organic waste materials have been carried out in the recent years.Studies to determine the specific methane potential of organic waste materials have a great importance for both design and economical operation of the biogas plants.Energy potential that will be recovered from organic wastes is substantial in Turkey.Thanks to biogas plants gathering vegetable-fruit wastes and other organic wastes are planned to produce significant amount of renewable energy in Turkish markets.Owing to the use of organic wastes,the disposal of waste as well as energy production,soil,water and air pollution in terms of environmental protection are also minimized.On the other hand,the organic wastes produced from plants can also be utilized as fertilizer in vegetable production.In this study,the cumulative biogas and methane production of vegetable and fruit wastes were experimentally determined with HBT(Hohenheim Batch Test)method.Biogas and methane yields of vegetable and fruit wastes were found as 0.54-0.73 Nm^(3)/(kg ODM)and 0.29-0.37 Nm^(3)/(kg ODM),respectively.The highest value of the cumulative specific methane production was tomato wastes(0.37 Nm^(3)/(kg ODM)),and the lowest value was lettuce wastes(0.29 Nm^(3)/(kg ODM)),as well.The average cumulative specific methane production values of mixed vegetable and fruit wastes are determined as 0.34 Nm^(3)/(kg ODM).

Development and testing of high precision and stability power supply for high energy photon source

Purpose The high energy photon source(HEPS)is the fourth-generation synchrotron photon source.Compared with the third-generation synchrotron photon source,the brightness is 100-1000 times higher,and the electron emittance of the storage ring is low to the diffraction limit of light.Through physical calculations,it is required that the stability of the storage ring quadrupole magnet power supply be better than 10 ppm,and the accuracy of output current be better than 80 ppm.This high demand for technical parameter poses a challenge to the development of high precision and stability power supplies.Methods The main circuit topology of the power supply adopts a phase-shifted full bridge soft switching scheme,which avoids interference caused by switching noise and improves power stability and efficiency.The high-precision digital power supply controller based on FPGA improves the sampling speed and control accuracy of the power supply,and the constant temperature control circuit ensures that the output current of the power supply meets the requirements of HEPS for power supply performance.Results In the batch testing section,a testing facility was built to test the stability,accuracy,repeatability,voltage ripple,and other parameter of high precision and stability power supplies.After a year and a half of testing,the performance tests of 1066 power supplies,including linear accelerators power supplies,booster power supplies,storage rings power supplies,dipole and quadrupole combined power supplies,dipole and quadrupole power supplies,were completed.The results all met and exceeded the design specifications.Conclusions The HEPS high precision and stability power supply meets the design requirements in terms of current stability,accuracy,repeatability,voltage ripple,and other aspects.The batch test results show that the power supply performance using the full bridge phase shifting soft switching technology combined with high-precision digital controller scheme is excellent,and the power supply consistency is good,providing a guarantee for the successful operation of HEPS in the future.