Municipal Liquid Waste Research Articles

Developing efficient nutrient removal and resource recovery strategy towards synergistic MLW treatment using macroalgae in a flat panel photobioreactor

The present study conceived a novel technology – ‘MARiNE photobioreactor (PBR): MacroAlgae Remediates Nutrients for Energy in PBR’. The technology targets the simultaneous treatment of desalination effluent and municipal liquid waste. The present study showcases the proof of concept wherein Ulva lactuca, a marine green macroalga, well-reported for its pollutant scavenging properties, has been explored for the synchronized treatment of two effluents, namely desalination effluent and municipal liquid waste and making it safe for marine discharge. A total nutrient removal of 94.1%, 80.4%, and 100% for COD, TN, and TP was achieved at an optimum HRT of 12 h with the highest biomass productivity of 340 g DW m−2 d-1. The study demonstrates MARiNE PBR to be a biologically cohesive strategy for rapid MLW remediation. A presumptive proposal for biorefinery of the generated biomass which enables recycling of the captured nutrients from the effluents is also proposed.

ADSORPTION PURIFICATION OF LIQUID WASTE FROM PHOSPHATES AND RESINOUS SUBSTANCES USING NATURAL ADSORBENT BASED ON SUNFLOWER BEADS

Among the physicochemical methods of deep extraction of pollutants from wastewater, adsorption is of great interest. Prospects for the use of sorbents from natural raw materials in wastewater treatment technologies based on a critical analysis of the technical literature are shown, the choice of research direction is substantiated. The use of natural adsorbent based on sunflower husk in the technology of wastewater treatment from phosphates and resinous substances at high content to minimize their anthropogenic impact on the environment is scientifically substantiated. The kinetics of adsorption of phosphates and resinous substances has been studied, the optimal parameters of adsorption purification have been established, and adsorption isotherms have been obtained. The theory of monomolecular adsorption (Langmuir and Freundlich equations) was used to characterize the sorbent based on sunflower husk and calculate the adsorption parameters. Experimental data on the degree of extraction of phosphates and resinous substances from wastewater using a natural adsorbent based on sunflower husk were obtained, and its specific surface area (200.06 m2/g) was experimentally determined. It was found that the highest efficiency of phosphate removal at the initial content of 21.25 mg/dm3 to 8.75 mg/dm3 from municipal liquid waste is achieved by adding an adsorbent in the amount of 10 g/dm3. With such technological parameters, the degree of waste treatment reaches 59.3%. At the increased concentration of resinous substances of 775 mg/dm3 at a dose of adsorbent of 1.5 g/dm3 duration of adsorption of 40 minutes their maintenance decreased to an extremely safe indicator (less than 25 mg/dm3). and implement them in urban and industrial treatment plants.

Rapid and de-centralized model for municipal effluent reclamation using microalgae

Abstract Microalgal bioremediation is currently being venerated for its potential in municipal liquid waste (MLW) treatment. Algae-based water treatment with retention time competitive to the conventional water treatment processes is a challenge. The present study investigated the role of algal biomass concentration to improve treatment efficiency to reduce the time required for water treatment. Eighty percent removal of pollutants (in terms of chemical oxygen demand (COD), ammonia, phosphate and fecal coliforms) was obtained in 12 hours at a biomass concentration of 1 gL−1. Further, continuous treatment of MLW using membrane-assisted photobioreactor was established. The treatment led to >95% removal of ammonia, >75% removal of COD and 100% removal of fecal coliforms within 12 hours. Physiological assessment of the algal culture showed that the cells did not manifest symptoms of stress throughout the reactor cycle, a consequence of continuous availability of the nutrients, maintaining the culture in continuous growth state.

Municipal liquid waste management: finding a solution

Municipal liquid waste management: finding a solution

Treatment and utilization of liquid communal waste in the cities

Treatment and further utilization of wastewater sludge are the important city service problem. The paper presents an efficient method of super high frequency irradiation for communal liquid waste such as wastewater sludge. The effect of microwaves on the properties of sediments, including the outlet of heavy metal ions in to water, is shown. Technical and economic indexes and results of experimental researches, indicating the opportunities of microwave irradiation in processes of sediments heating, are presented. The influence on sludge temperature of some technological SHF parameters has been studied. Because of statistic analyze, a regression polynomial equation describing the heating of sludge mixture has been obtained. The microwave and electro thermal processing of municipal liquid waste taken from a city’s wastewater plants have been compared. Energy efficient economy of microwave irradiation using for municipal wastewater sediments have been confirmed.

Energy efficiency in municipal waste treatment

The article presents the efficient method of microwave irradiation (SHF) for the municipal liquid waste such as domestic wastewater and sludge. The technical and economic parameters and experimental data, showing the possibilities of microwave electromagnetic radiation using in the sewage and sediment treatment technologies, are given in this article. The traditional electrothermal treatment and SHF processing of the municipal precipitation, taken from the city wastewater treatment plant, have been compared. At the same time, a high rate of heating of the precipitation samples has been noted during the microwave treatment. The technical and economic comparison of three methods (with the usage of the reagents, convection heating and SHF) showed the advantages of using SHF range electromagnetic radiation. The energy efficiency and the cost-effective use of resources during the SHF using for liquid municipal waste treatment have been confirmed.

Thermotolerant yeasts capable of producing bioethanol: isolation from natural fermented sources, identification and characterization

ABSTRACTRecently, the demands of biofuels have increased, because of their significant role in reducing various pollutants created by fossil fuels. Here, we have collected 25 samples containing various thermotolerant microorganisms from the nine natural fermented sources of Bangladesh, such as Boiled potato (Bp), Decomposed foods (Df), Municipal liquid waste (Mlw), Municipal solid waste (Msw), Sugarcane juice (Sc), Pantavat (Pv), Sugar molasses (Sm), Tari (Tari) and Watermelon juice (Wm) for bioethanol production. Among them, 18 isolates are capable of producing bioethanol. Cultural, morphological, physiological, biochemical and genetic analyses were carried out under various physiological conditions. Ethanol fermentation was checked by different carbon sources, temperatures and pH. All of the isolates could grow well in the medium containing Dextrose and Arabinose and only two strains Pv-1 and Bp-2 could ferment Xylose as a sole carbon source. At 42 °C, the highest ethanol concentration 6.58% (v/v) was obtained by a strain Wm-1 isolated from Watermelon juice. At 37 °C, maximal ethanol concentrations of 6.74% (v/v), 6.50% (v/v) and 6.22% (v/v) were obtained by the strains Bp-2, Wm-l and Pv-1, respectively. Among the various pH tested, the highest ethanol concentration 6.6% (v/v) was obtained at pH 4.5 by a strain named Tari-2. Finally, yeast 26S rDNA sequencing information identified the strains Sc-2 as Saccharomyces cerevisiae Pv-2, Tari-2 and Df-1 as Pichia kudriavzevii, Mlw-l and Bp-2 as Candida tropicalis, Pv-1 as Pichia guilliermondii and Df-2 as Candida rugosa.

Effect of municipal liquid waste on corrosion susceptibility of galvanized steel pipe

This investigation studied the effect of municipal liquid waste discharged into the environment within Kano municipal area on the corrosion susceptibility of galvanized steel pipe burial underground. Six stagnant and six moving municipal liquid waste samples were used for the investigation. The corrosion rate of the galvanized steel pipe was measured using the gravimetric technique. The results obtained from weight loss measurement shows a serious corrosion effect of municipal liquid waste on the galvanized steel pipe. The overall corrosion rates are much higher in the stagnant and moving liquid waste samples collected within the core city than the liquid waste samples collected outside the city, but become low with the formation of passive films on galvanized steel surface after 2500 hours. Therefore, this investigation revealed that the galvanized steel pipes used to supply the city with pipe borne water are at high risk of supplying contaminated water due to some leaking pipes. Key words: Liquid waste, galvanized steel, weight loss, ravimetric, corrosion, leaking

Upscaling relative permeabilities in a structured porous medium

Upscaling of multi-phase flow problems for a heterogeneous porous medium requires modification of constitutive functions at the grid-block scale. A particular type of heterogeneity that has important environmental consequences involves thin, continuous streaks of high permeability through lower-permeability background rocks. These streaks, which may correspond to features like abandoned wells in mature sedimentary basins, can become preferential flow paths for an invading fluid. Quantification of flow through these types of heterogeneities in deep, geological formations is necessary for estimates of migration and possible leakage of injected fluids such as hazardous liquid wastes, municipal liquid wastes, and, possibly, carbon dioxide. One of the important constitutive functions for proper estimation of flow through these flow paths is the relative permeability function. In the simple case of a single high-permeability streak in a uniform rock matrix, with both materials having identical (local) relative permeability functions, the upscaled relative permeability must be changed significantly to capture the proper leakage. Standard petroleum reservoir pseudo-functions for relative permeability capture the general features of the upscaled function, but they still produce errors of several hundred percent in the leakage estimation. Detailed three-dimensional numerical simulations and associated upscaled calculations demonstrate the proper form for the upscaled relative permeability, and provide a modified derivation of pseudo-functions to capture the leakage behavior in upscaled models.

Hydrogeology of deep-well disposal of liquid wastes in southwestern Florida, USA

Deep-well injection has been used to dispose of municipal liquid wastes in southwestern Florida since 1988. The liquid wastes are injected into an extremely high-transmissivity zone of fractured dolomite in the Early Eocene Oldsmar Formation of the Floridan aquifer system; this zone is commonly referred to as the Boulder Zone. Data collected during the drilling and operational testing of southwestern Florida injection wells provide insights into the nature of the injection zone and overlying confining beds. The location of high-transmissivity zones that are capable of accepting large quantities of waste water is vertically and horizontally variable and cannot be predicted with certainty. A 40.9-m thick high-permeability interval in one injection well, for example, was absent in a well drilled only 85.4 m away. Some upward migration of low-density injected fluids has occurred, but at no site were the injected liquids detected in deep monitor wells, such as occurred at injection-well sites along the coasts of southeastern, west-central, and east-central Florida. The primary confinement of the injected liquids (i.e., deepest effective confining beds) consists of unfractured beds of low-permeability dolomite within the Oldsmar Formation, whose locations are also laterally and vertically variable. The origin and controls of the distribution of fractures in the Oldsmar Formation are poorly understood.

Disinfection of sewage wastewater and sludge by electron treatment

The use of machine-accelerated electrons to disinfect sewage waterwaste and sludge is discussed. The method is shown to be practical and energy-efficient for the broad spectrum disinfection of pathogenic organisms in municipal wastewaters and sludge removed from them. Studies of biological, chemical and physical effects are reported. Electron treatment is suggested as an alternative to chlorination of municipal liquid wastes after electron treatment to provide disinfection. Disposal of sewage sludge is recommended as an agricultural resource by subsurface land injection, or as a nutrient for fish populations by widespread ocean dispersal.

Late Tertiary and Quaternary Depositional Systems in Subsurface of Central Texas Coastal Plain: ABSTRACT

Late Miocene, Pliocene, and Pleistocene deposits in the subsurface of the central Texas coastal plain were subdivided into six operational units equivalent to the surface-defined Fleming, Goliad, Willis, Lissie, and Beaumont Formations. These sedimentary units constitute the last major depositional episodes in the northwestern Gulf Coast basin. Late Miocene deposition is represented by transgressive shelf and shallow-marine shales overlain by progradational clastics of the upper part of the lower Fleming, upper Fleming, and lower Goliad-Willis units. A minor Pliocene transgressive event is represented by downdip, marine embayment facies of the upper Goliad-Willis unit. Finally, Pleistocene highstand fluviodeltaic progradation (Lissie and Beaumont units) terminated pre-Hol cene sedimentation. Interpretation of sediment distribution, established by constructing a series of net and percentage sand-maps for each unit, permits delineation of the following main depositional systems: fluvial braided-meander belt and flood basin; fluviodeltaic; lagoon; large marine embayments; small bayhead deltas; thick wave-dominated deltas; strand plain; and thick stacked coastal barriers. Western fluviodeltaic systems were consistently less active than the eastern ones, which deposited greater volumes of sand. Inherited, subtle structural influence of the deeper seated San Marcos arch had some effect on sediment distribution and paleogradients. Shallow extensions of the deeper Vicksburg, Frio, and Miocene fault systems display respectively decreasing (from 400 ft or 122 m) displacements in the section studied. Faults clearly were a central factor in the distribution of fluvial, deltaic, and strike-oriented coastal sands. Most sands in the updip parts of the operational units contain fresh water, whereas those of downdip areas contain predominantly brackish to saline waters. The area with greatest reservoir potential for fresh water includes Victoria, Jackson, Wharton, and Colorado Counties. Possible use of sealed, thick coastal sands in the lower Fleming unit for the disposal of industrial and municipal liquid-waste is recommended. End_of_Article - Last_Page 1689------------

Injection of Acidic Industrial Waste into Saline Carbonate Aquifer--Geochemical Aspects: ABSTRACT

A section of carbonate rocks that includes several highly permeable cavernous zones filled with saline water underlies the south part of peninsular Florida at depths from 1,500 to 4,500 ft. Because these cavernous zones are capable of yielding or accepting large quantities of fluids, they are used for storage of industrial and municipal liquid waste at several places. One such place is at the south end of Lake Okeechobee near Belle Glade, Florida, where the effluent from a sugar mill and liquid waste from the production of furfural processed from sugar cane bagasse have been injected at depths between 1,500 and 2,200 ft. The waste ranges in temperature from 71 to 103°C, in pH from 2.6 to 4.5, and is highly organic (COD 6,000-26,000 mg/l). Since 1966 more than 800 mil ion gal of this waste have been injected. Injection rates range from 400 to 800 gal/minute at pressures of 30-60 psi at the well-head. The waste is partly neutralized almost immediately to a pH of 5.5 by dissolution of limestone. Caliper logs show localized patterns of dissolution of the carbonate aquifer. Anaerobic degradation of the organic waste begins near the injection well, as indicated by the presence of hydrogen sulfide, methane, carbon dioxide, and nitrogen. The waste has moved both upward and laterally in the aquifer system, as detected by water quality changes in monitor wells. Upward movement of altered waste into an overlying brackish-water zone was detected by a 1,400-ft monitor well 75 ft away from the injection well. Lateral movement was detected by a monitor well in the injection zone 1,000 ft away. When upward movement of waste was detected, injection was discontinued and the well was drilled and cased several hundred feet deeper. Data collected since the well was deepened are inconclusive regarding the effectiveness of the increased well depth in restricting the waste to the injection zone. Investigations to date at Belle Glade clearly point up the value of a sound monitoring program. End_of_Article - Last_Page 1597------------