Automatic control of the water content of porcelain filter press cakes

Hydraulic conductivity of sand-bentonite (SB) backfills amended with polyanionic cellulose (PAC) to lead nitrate (Pb(NO3)2) solutions was evaluated experimentally in this study. PAC-amended sand-bentonite (PSB) backfills were synthesized by mixing sand-bentonite mixture with 0.3 to 1.2% dry PAC (by total dry mixture mass) and mixed with a certain weight of conventional bentonite (CB) slurry. The rheology properties including the filtrate loss, viscosity, density, and pH testes of slurry with various bentonite dosages were measured to determine the reasonable CB dosage of slurry. The slump tests on PSB backfills with various mass slurries were conducted to determine the corresponding water content of backfills with slump 125 ± 5 mm. Under the applied pressure 100 kPa, the hydraulic conductivity to Pb(NO3)2 solutions (kc) of PSB backfills with various PAC contents was evaluated based on the modified filter press (MFP) tests, to ascertain the optimum PAC content of PSB backfills when permeated with Pb(NO3)2 solutions. Index properties, including the specific gravity (Gs) and liquid limit (wL) of PSB backfills, were measured after MFP tests. The MFP tests for PSB backfills were then conducted under various applied pressures to obtain the relationship between void ratio (e) and hydraulic conductivity of backfills. Finally, the flexible-wall permeability test (FWP test) under osmotic pressure 100 kPa was conducted to verify the effectiveness of the MFP test. The results indicate that slurry with 8% bentonite dosage is the reasonable choice in slurry wall construction. PSB has lower GS and higher wL compared to SB; increasing Pb concentration leads to GS of PSB increased and wL of PSB decreased. PSB with 0.6% PAC content is supposed as the optimum proportion of backfills when permeated with concentrated Pb(NO3)2 solution. PAC adsorbs large amount of bound water, which leads to higher water content (w) and e of PSB backfills, while lead ions (Pb) cause the diffuse double layer (DDL) of bentonite compressed and e of PSB backfills reduced. The kc of PSB-0.6 remains lower than 10−9 m/s and increases less than 10 times though the Pb concentration was up to 500 mM, demonstrating that the hydraulic performance of backfills can be improved effectively in Pb(NO3)2 solution by the additive PAC. The comparison results between k from MFP tests and FWP tests show that the MFP test is an effective and easy evaluation of hydraulic conductivity of backfills.

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Commercialization of Pressurized Electroosmotic Dehydrator (PED)

Water Science & Technology ◽

10.2166/wst.1990.0120 ◽

1990 ◽

Vol 22 (12) ◽

pp. 259-268 ◽

Cited By ~ 33

Author(s):

S. Kondoh ◽

M. Hiraoka

Keyword(s):

Activated Sludge ◽

Water Content ◽

Treatment Process ◽

Waste Water Treatment ◽

Filter Press ◽

Carbon Electrodes ◽

Water Treatment Process ◽

The World ◽

First Time ◽

Scanning Electron

Application of electroosmosis to conventional filter press dehydrators has been studied to decrease water content in the sludge generated from waste water treatment process. Experiments realized the reduction of water content in the biological excess activated sludge down to 50-60%, which had never been achieved by the conventional dewatering method. The new method has been commercialized by pre-concentration of the excess activated sludge, addition of electrolyte, and development of special carbon electrodes. Moreover, observation using a scanning electron microscope enabled us to demonstrate the suitability of the PED process to the excess activated sludge. The newly-developed dehydrators and processes have been operating successfully at three commercial plants for the first time in the world.

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Effect of Pressure Differences on Sludge Filtration Process Efficiency by Using Plate Filter Press

Journal of Vocational Studies on Applied Research ◽

10.14710/jvsar.v1i2.6280 ◽

2019 ◽

Vol 1 (2) ◽

Author(s):

Qurrotun A'yuni Khoirun Nisa'

Keyword(s):

Water Content ◽

Waste Treatment ◽

Solid Material ◽

Filter Press ◽

Process Efficiency ◽

Residential Areas ◽

Settling Basin ◽

A Value ◽

Plate Filter ◽

Resistance Value

Waste treatment in the industry produce sludge from the settling of solid material as a by product of the treatment process. The resulting sludge can’t be thrown away in large quantities because it can cause problems if there is still water content in it especially for industrial centers located around residential areas. So that filtration is carried out on the sludge from the Sedimentation Tub at the WWTP know in the area of Lamper, Semarang with the aim of reducing the volume of sludge by separating the water from the sludge before being discharged. The results of the analysis of the sludge filtration in the Settling Basin at WWTP obtained the value of cake resistance at a pressure of 75 kg / m2 of 4.42E + 11 m/kg, at a pressure of 90 kg/m2 of 5.62E + 11 m/kg and at a pressure of 104 kg/m2 of 6.74E + 11 m/kg. The results of the analysis on the resistance value of the filter medium obtained a value of 1.59E+12m-1 at a pressure of 75 kg/m2, 1.23E+12 m-1 at a pressure of 90 kg/m2 and 1.61E+12 m-1 at a pressure of 104 kg/m2. While in the analysis of water content, at a pressure of 75 kg/m2 obtained a value of 35.437%, at a pressure of 90 kg/m2 obtained a value of 35.024%, and at a pressure of 104 kg/m2 obtained a value of 34.024%. Efficiency The optimal pressure is 104 kg/m2.

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Functionality of Process Control in Moulded Goods Production

E3S Web of Conferences ◽

10.1051/e3sconf/201910501006 ◽

2019 ◽

Vol 105 ◽

pp. 01006 ◽

Cited By ~ 1

Author(s):

Olga Puhova ◽

Vladimir Lebedev

Keyword(s):

Process Control ◽

Automatic Control ◽

Water Content ◽

Automatic Regulation ◽

Automatic Process ◽

Automatic Process Control ◽

Custom Made ◽

Mineral Components ◽

And Control ◽

Measurement And Control

The article presents the findings of the research in the field of automatic control of peat mass quality in hollow peat pot production. The strength of the finished product determines its integrity and crumblability which affect the loss during drying and transportation. Therefore, knowing the strength characteristics we can use them for quality control. Besides, not strength but heterogeneity in the distribution of pores, moisture, and density is responsible for crumbling. Automatic regulation of effective peat mass water content is one of the main stages determining the quality. At this stage automatic control of the flow, dispersion and water content of peat mass entering the pulper tank as well as measurement and control of the amount of additional elements introduced, such as mineral components, wood pulp, and water to form the required consistency, are provided for. The models of automatic process control are built and analyzed with the methods of differential equation theory, numerical integration, and stability theory. The model is implemented with the custom-made proprietary software. The model adequacy is determined empirically by comparing the data obtained on the model with the actual technological process.

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Characterization of frozen hydrated biological specimens by low-loss EELS

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132492 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1572-1573

Author(s):

Songquan Sun ◽

Richard D. Leapman

Keyword(s):

Water Content ◽

Direct Method ◽

Internal Standard ◽

Dry Weight ◽

Dark Field ◽

Protein Solutions ◽

Subcellular Compartment ◽

Differential Shrinkage ◽

Electron Energy Loss

Analyses of ultrathin cryosections are generally performed after freeze-drying because the presence of water renders the specimens highly susceptible to radiation damage. The water content of a subcellular compartment is an important quantity that must be known, for example, to convert the dry weight concentrations of ions to the physiologically more relevant molar concentrations. Water content can be determined indirectly from dark-field mass measurements provided that there is no differential shrinkage between compartments and that there exists a suitable internal standard. The potential advantage of a more direct method for measuring water has led us to explore the use of electron energy loss spectroscopy (EELS) for characterizing biological specimens in their frozen hydrated state.We have obtained preliminary EELS measurements from pure amorphous ice and from cryosectioned frozen protein solutions. The specimens were cryotransfered into a VG-HB501 field-emission STEM equipped with a 666 Gatan parallel-detection spectrometer and analyzed at approximately −160 C.

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STEM measurement of subcellular water distributions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148678 ◽

1993 ◽

Vol 51 ◽

pp. 568-569

Author(s):

R.D. Leapman ◽

S.Q. Sun ◽

S-L. Shi ◽

R.A. Buchanan ◽

S.B. Andrews

Keyword(s):

Water Content ◽

Internal Standard ◽

Dry Weight ◽

Dry Mass ◽

Scanning Transmission Electron Microscope ◽

Dark Field ◽

Bulk Water ◽

Inelastic Electron ◽

Scanning Transmission ◽

Annular Dark Field

Recent advances in rapid-freezing and cryosectioning techniques coupled with use of the quantitative signals available in the scanning transmission electron microscope (STEM) can provide us with new methods for determining the water distributions of subcellular compartments. The water content is an important physiological quantity that reflects how fluid and electrolytes are regulated in the cell; it is also required to convert dry weight concentrations of ions obtained from x-ray microanalysis into the more relevant molar ionic concentrations. Here we compare the information about water concentrations from both elastic (annular dark-field) and inelastic (electron energy loss) scattering measurements.In order to utilize the elastic signal it is first necessary to increase contrast by removing the water from the cryosection. After dehydration the tissue can be digitally imaged under low-dose conditions, in the same way that STEM mass mapping of macromolecules is performed. The resulting pixel intensities are then converted into dry mass fractions by using an internal standard, e.g., the mean intensity of the whole image may be taken as representative of the bulk water content of the tissue.

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