Catalytic gasification of coal using eutectic salts: recovery,regeneration, and recycle of spent eutectic catalysts

Catalyst recovery studies were conducted for gasified chars produced from steam gasification of Illinois #6 coal catalyzed with two different catalyst systems. A ternary (43.5 mol% Li2CO3-31.5 mol% Na2COr-25 mol% K2CO3) and a binary (29 mol% Na2CO3-71 mol% K2CO3) eutectic catalyst system were used for gasifying coal. Various extraction schemes, such as water extraction, H2SO4 extraction, and acetic acid extraction, were evaluated with respect to their extraction efficiencies. Effects of major process variables, such as solvent-to-char ratio, mixing time, temperature, and concentration, on the extraction efficiency were evaluated. A process schematic for the entire catalyst recovery, regeneration, and recycle scheme was developed and the preliminary process economics were determined based on these extraction schemes. H2SO4 extraction was found to be the most desirable. It also turned out to be more attractive than a once-through throwaway system.     

A review of textile industry: Wet processing,environmental impacts,and effluent treatment methods

The word “textile” means to weave and was taken from the Latin word “texere.” Nowadays, textiles not only fulfill humankind's basic necessity for clothing, they also allow individuals to make fashion statements. As one of the oldest industries, the textile industry occupies a unique place in India. It is responsible for 14% of the total industrial manufacture in India. However, the textile industry is also considered to be one of the biggest threats to the environment. Pretreatment, dyeing, printing, and finishing operations are among the various stages of the industrial textile manufacturing process. These fabrication operations not only utilize huge quantities of power and water, they also generate considerable amounts of waste. The textile industry utilizes a number of dyes, chemicals, and other materials to impart the required qualities to the fabrics. These operations produce a significant amount of effluents. The quality of effluents is such that they cannot be put to other uses, and they can create environmental problems if they are disposed of without appropriate treatment. This review discusses different textile processing stages, pollution problems associated with these stages, and their eco‐friendly alternatives. Textile wet processing is described in detail, as it is the key process in the industry and it also generates the greatest amount of pollutants in textile processing. The environmental impact of textile effluents is discussed, as textile effluents not only impose negative effects on the quality of water and soil, they also imperil plant and animal health. In this paper, various methods for treating textile effluents are described. Discussion of physical, chemical, biological, and advanced treatment technologies of effluent treatment are included in this paper.     

Biochemical and histological alterations induced by a formulation of dicofol in the embryonic liver of Gallus domesticus

In the present investigation, hepatotoxic effect of a commercially available insecticide formulation of dicofol (Colonel–S® 18.5% emulsified concentrate) was studied in the developing chick embryo. Fertilized eggs of Gallus domesticus were immersed in three different dose concentrations, i.e. 250, 500, and 1000 mg L^?1 of Colonel–S on “0” and fourth days of incubation for 60 min at 37 °C and incubated till embryonic day 16. Severe histopathological cellular lesions, such as extensive cell degeneration and necrosis with enlarged blood sinusoids, cytoplasmic vacuolization, and leucocyte infiltrations with congestion or dilation of central vein, appeared in dose-depended manner. Dicofol treatment also caused significant decrease in the levels of total protein, glycogen, and glutathione content and an increase in alkaline phosphatase activity of embryonic liver, whereas glutamic pyruvic transaminase activity showed mixed response.     

Bioremediation of industrial waste through mushroom cultivation

Handmade paper and cardboard industries are involved in processing of cellulosic and ligno-cellulosic substances for making paper by hand or simple machinery. In the present study solid sludge and effluent of both cardboard and handmade paper industries was collected for developing a mushroom cultivation technique to achieve zero waste discharges. Findings of present research work reveals that when 50% paper industries waste is used by mixing with 50% (w/w) wheat straw, significant increase (96.38%) in biological efficiency over control of wheat straw was observed. Further, cultivated basidiocarps showed normal morphology of stipe and pileus. Cross section of lamellae did not show any abnormality in the attachment of basidiospores, hymenal trama and basidium. No toxicity was found when fruiting bodies were tested chemically.     

Groundwater resource assessment, categories, and typologies: case study, Andhra Pradesh, India

In India, groundwater assessment units are classified as overexploited areas, critical areas, semi-critical, or safe areas based on the stage of groundwater development and long-term water level trends. Intuitively, in the safe units, wells are expected to function and have good yields. Besides, in the safe units, new wells are expected to be successful. Conversely, the expectation of a successful well or wells with good yields is much lesser in the overexploited units. However, when these expectations are not met in the field, doubts are raised about the quality of assessment and its usefulness, and there is outright distrust on the agencies assessing groundwater resource by the common man as well as on the planners, administrators, and the politicians. Therefore, there is a need to present the results in a way that does not create confusion. One of the methods is to combine the assessment results with aquifer characters using geographic information system (GIS); when this is done, a whole set of newer classes emerge, which can be mapped. These classes are termed as groundwater typologies in this study. Each typology has some characteristics or traits in common, which include basic aquifer character as well as the stage of groundwater development. Thus, a class may be safe, but if the aquifer is poor, then it is separated from a class that is safe and where the aquifer is good and so on. In Andhra Pradesh, which is taken as the case study for this purpose, eight main typologies emerged, and two of these main typologies were further divided into four subtypologies each. This new way of understanding the pattern of groundwater abstraction (using GIS) has a better visual impact. Groundwater typologies are found to be much more rational and useful in developing management strategies, rather than simple listing as overexploited areas, critical areas, semi-critical areas, and safe areas as is commonly done. The typologies so delineated indicate on the map (or table) that balanced usable groundwater is in between 5 and 6 bcm/a as against the estimated balance of 20.5 bcm/a, and it is largely in poor hard rock type of aquifers, which occupy about a third of the area of the state.     

Integrated process approach for degradation of p-cresol pollutant under photocatalytic reactor using activated carbon/TiO2 nanocomposite: application in wastewater treatment

Environmental Science and Pollution Research - Over the years, biodegradation has been an effective technique for waste water treatment; however, it has its own limitations. In order to achieve a...     

Mutagenicity assessment of textile dyes from Sanganer (Rajasthan)

Sanganer town, district Jaipur (Rajasthan, India) is famous worldwide for its hand block dyeing and textile printing industries. These industries use a variety of chemicals and dyes during processing and finishing of raw materials. Most of the textile dyes used by these industries have not been evaluated for their impact on health and the environment. The workers in these industries are exposed to such dyes with no control over the length and frequency of exposure. Further, untreated and sometimes even treated effluents from these industries are released into surface waters of Amani Shah drainage or through the drainage systems, seep into the ground water and adjoining water bodies. Since many textile dyes are known carcinogens and mutagens, a complete evaluation of the safety of these dyes in the human environment must include an evaluation of their genotoxicity or mutagenicity. A total of 12 textile dyes from Sanganer were tested for their mutagenicity, by Ames Salmonella reversion assay using strain TA 100 of Salmonella typhimurium. Only 1 dye, Red 12 B showed absence of mutagenic activity. The remaining 11 dyes were all positively mutagenic.     

Groundwater Pollution Around an Industrial Area in the Coastal Stretch of Maharashtra State, India

The main objective of this paper is to examine pollution threat, especially to the groundwater resources, around Tarapur industrial area (also called the Tarapur MIDC area) located on the Arabian Sea Coast in Thane District of Maharashtra State, India and suggest remedial measures that may also be relevant to other industrial areas on the Indian Sea Coast. One hundred and thirty one samples were collected from various sources, such as dugwells, borewells, dug-cum-borewells, effluent sumps, drainage channels (effluent channels), creeks and ocean, for chemical analyses. These analyses show that the area in general is characterized by hard water and high salinity hazard, possibly due to its proximity and hydraulic connection with the sea. Although the potability of groundwater is questionable in certain pockets, it is good enough for irrigation purposes at present. Low pH value and high heavy metal contents in the adjoining Muramba creek water is a matter of great concern and may be attributed to the indiscriminate disposal of industrial effluents to the drainage channels connecting the creek. Muramba Creek is well connected with the Arabian Sea, and there are evidences of seawater intrusion around this creek. Because of the fact that Muramba Creek is highly polluted, and is hydraulically connected with the dugwells and borewells surrounding the creek, it cannot be ruled out that the groundwater around this creek is susceptible to contamination. Unless measures are not taken immediately to stop the indiscriminate disposal of the solid wastes and liquid effluents in open ground and drainage channels, and measures are not taken to maintain the appropriate pH values at the effluent treatment facilities before their disposal, the problem would indeed be formidable one day, and it will be too late then for the authorities to take care of the resulting maladies. Few suggestions have been given for controlling and managing the industrial pollution around the Tarapur MIDC area. These suggestions are relevant to other industrial areas situated on the 7,000 km long Indian Sea Coast.