Comparative Study on Mechanic Workshop Polluted Soil Treated With Lime (Citrus Aurantifolia) Juice, Powder and Inorganic Lime Fertilizer

An assessment of mechanic workshop polluted soil treated with 16.6% lime juice (MSAL), mechanic workshop polluted soil treated with lime powder (MSLP) and mechanic workshop polluted soil treated with inorganic lime fertilizer (MSLF) was conducted for a period of 56 days. The study revealed higher microbial counts in the treated soils compared to mechanic oil free soil (MFS). The total viable bacterial counts observed ranged from 1.6×104 cfu/g to 6.8×104 cfu/g for MSF, 2.2×104 cfu/g – 26.2×104 cfu/g for MSAL, 1.2×104 cfu/g -17.2×104 cfu/g for MSLP and 6.8× 104 cfu/g – 16.0 × 104 cfu/g for MSLF while fungi counts ranged from 2.5×104 cfu/g to 6.4×104 cfu/g for MFS, 4.0×104 cfu/g – 16.4×104 cfu/g for MSAL, 2.6×104 cfu/g -3.8×104 cfu/g for MSLP and 2.1× 104 cfu/g – 4.0 × 104 cfu/g for MSLF. Organisms isolated in the course of the study includes Pseudomonas sp, Staphylococcus sp, Bacillus sp, Micrococcus sp, Escherichia coli, Proteus sp, Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Mucor sp, Saccharomyces sp, and Rhizopus sp. The physicochemical results showed that MSAL had higher moisture content, organic matter content, organic carbon, and nitrate than MSF, MSLP and MSLF. There were significant differences in pH, organic matter content, organic carbon, nitrate and phosphorus at 0.05 probability level, but there was no significant different in the moisture content of the soil undergoing treatment. This is an indication that Lime juice has a greater potential in bioremediation of mechanic workshop polluted soil compared to lime powder and inorganic lime fertilizer.

Effect of Limestone Powder on Mechanical Properties of Engineering Cementitious Composites

The effect of limestone powder replacing fly ash on the mechanical properties of engineering cementitious composites was investigated. The results showed that the water demand of engineering cementitious composites due to partial replacement of fly ash by limestone powder, but the water demand of the system decreased when the replacement ratio reached 100%. The flexural strength of the specimen appears to decrease with increasing age due to incomplete replacement of lime powder. The toughness of the specimen can be significantly improved due to the complete replacement of fly ash by limestone powder.

The influence of lime powder on the behaviour of clay soil

High price of land and importance of modern construction has imposed the need to strengthen weak clay soils. The stabilization of these soils has been conducted using various additives. Due to its low cost, availability, and positive impact on resistance, lime has traditionally been applied for stabilisation of poor and sensitive types of soils. In this research, lime powder, added in the percentages of 0, 2, 4, 8 and 16 of the dry soil weight, was mixed with kaolinite clay soil and its various engineering parameters were investigated during the curing time of 90 days. PH change, Atterberg Limits, optimum water content, and the modified clay maximum dry unit weight, were determined at different percentages of lime during the curing time. In the scope of determination of an optimum lime powder content, the Unconfined Compressive Strength tests (UCS) and CBR tests were conducted. The Young’s modulus was determined based on UCS testing and definition of stress-strain curve. The results showed a significant increase in the effective, responsive performance of lime in the soil and a remarkable increase in the maximum compressive strength (qu), cohesion, and Young’s modulus.

Metallurgical properties of iron ore pellet when using lime powder instead of bentonite

This paper reported effects of lime powder and bentonite binder using in iron ore pelletization on metallurgical properties of pellets as green strength, compressive strength and degree of reduction. The investigated pellets contain 0, 1 and 2 mass % of lime powder and 2, 1 and 0 mass % of bentonite, respectively. Green balls were dried (105 °c for 24 hours) then heated at 1200 °c for 30 minutes. The reductibility of fired pellets was examined at different temperatures of 900, 1000 and 1100 °c with various holding time (45, 90 and 120 minutes). The results showed that the combination of 1 mass % of bentonite and 1 mass % of lime powder in the pellet gave the most apropriate metallurgical properties of pellets as green strength, porosity and degree of reduction. This material charging ratio can be recommended for application in manufacturing of the pellet.

Farm use of calcium hydroxide as an effective barrier against pathogens

Livestock farming is affected by the occurrence of infectious diseases, but outbreaks can be prevented by proper sanitary control measures. Calcium hydroxide (Ca(OH)2), commonly called slaked lime, powder is traditionally used as a disinfectant to prevent infectious diseases in livestock. Since Ca(OH)2 can inactivate a wide variety of pathogens, has a small environmental impact, does not require a disinfection tank (i.e., can be spread directly on the ground) and is produced inexpensively worldwide, it is used for the prevention of epidemics on farms worldwide. Water is essential for the strong alkalinity that underlies its disinfecting effect, but it is unknown how much water is required under field conditions. In addition, Ca(OH)2 reacts with carbon dioxide in the environment, reducing its pH, but it is unclear how long its degradation takes under actual field use. Thus, we measured the water adsorption ability of Ca(OH)2-based disinfectants and its relation to disinfectant activity, as assessed by colony counts and live/dead staining and observation. We found that 15–20% (w/w) water in Ca(OH)2 was necessary for disinfection to occur in practice. Moreover, we found that the pH of Ca(OH)2 decreased within about two weeks to one month under actual use in practical conditions and lost its ability to disinfect. We further showed that granules prepared from Ca(OH)2 and zeolite maintained high alkalinity more than twice as long as calcium powder. These findings will help to establish a suitable method of applying Ca(OH)2 to protect farms from infectious diseases.

Detection, Screening and Molecular Characterization of Potential Actinobacterium from Lime-dwelling Powder for Extra Cellular Cellulase

Actinobacteria, conventionally known as actinomycetes are the most unique microorganisms revealing a link between bacteria and fungi. They are highly adaptable to extreme environmental condition and also exhibit a high diversity in metabolic activities. Biochemical, physiological and genetic features are mainly responsible for their higher adoptability to harsh conditions and extra cellular synthesis of wider secondary metabolites in general and enzymes and antibiotics in particular. The limestone quarry and lime powder dwellings are the harsh habitats prevailing in the northern region of Karnataka. These are the typical habitats left behind after the exploration of limestone and lime powder for highly commercial industrial activities such as production of cement and petroleum refining process respectively. In the present investigation, efforts were made to detect cellulolytic actinobacteria from lime powder dwellings. Actinobacteria confirmed by the basic colony characters, microscopic features, biochemical and physiological properties were screened for the potential cellulolytic activity. In all 54 isolates of actinobacteria were detected and screened to obtain three best cellulolytic actinobacteria, namely DSA22, DSA38 and DSA39. The maximum zone of hydrolysis on carboxymethylcellulose medium was an important criterion to screen the best cellulolytic isolates of actinobacteria. Further, the three best isolates of cellulolytic actinobacteria were screened for maximum production of extra cellular cellulase. The isolate DSA22 with higher enzyme activity (12 IU) was subjected to molecular characterization. Based on 16s rRNA analysis (BioEra Laboratory, Pune, Maharashtra) an isolate DSA 22 was identified as Streptomyces enissocaesiles.

Experimental Studies on Compressive Strength of Aerated Concrete with Varying Percentage of Aluminium Powder

Today the disposal of various by-product materials is a concern against the environment, these are producing due to rapid industrial growth in our country. Most of the researchers are focused on the utilization of these by-products in the civil engineering construction industry. By using these by-products, on one hand, will protect the environment and other hands the disposal problem will be solved. Day by day the requirement of building materials increased due to urbanization, due to this more raw materials are required and depleted the natural resources. In this contest, environmental protection is need to protect incremental temperature in nature. To avoid these problems of the modern era, aggregation of these by-products can be used as one of building material and to overcome this situation, Aerated concrete is one of the solutions by reducing the raw material quantity in concrete like sand and cement by introducing air without compromising in the volume. Day to day aerated concrete has become popular due to lightweight and high insulation against temperature and sound. This concrete is using in high raised buildings to reduce the self-weight of building to protect during earthquake situations. In this experimental study mainly performed the compressive strength of aerated concrete with replacement of sand by quarry dust. Also reducing the cement content with replacement of fly ash, GGBS and lime powder at various percentages that is ranging. the performance of aerated concrete was observed more satisfactory when compared with and without replacement of above-saided materials.