Content Of Water-soluble Salts Research Articles

ГЛИНИСТОЕ СЫРЬЕ ДЛЯ ПРОИЗВОДСТВА СВЕТЛООКРАШЕННОГО КЕРАМИЧЕСКОГО КИРПИЧА В АСПЕКТЕ ВЫСОЛООБРАЗОВАНИЯ СОЛЕЙ ВАНАДИЯ

Ceramic lining brick is the most eco-friendly material and it is widely spread in modern construction. To date, the brick of light colors is of particular interest among consumers (peach, straw, beige, etc.). One of the main problem of brick constructions which impair technical and aesthetical properties is the salt weathering on the ceramic masonry surface. The reasons for this phenomenon are various-high content of water-soluble salts in clay raw materials, migration of salts from cement masonry, water hardness, etc. There are plenty methods to reduce damage and protect lining brick from salt efflorescence but raw materials selection and preliminary analysis of its liability to salt weathering is of particular importance. This paper addresses to the occurrence causes and microstructure of vanadium salts on the light-tone lining brick. The mineral composition, physical and molding properties of raw clay materials from Bolshaya Karpovka, Talalaevskoe, Chasov-Yarskoe deposits is analized from the standpoint of vanadium salt efflorescence. It is found that salt formation on the test sample surface consists of alkalis sulphates and calcium vanadates from the greenish-yellow to orange colors. The paper provided recommendations for using above-mentioned clays in light-tone ceramic brick manufacturing.

Scientific Substantiation of Introduction of Systems of Small-Intensive Irrigation Under Conditions of Mineral Farming in Azerbaijan

The study of the world experience and the results of long-term experiments with drip irrigation systems in the Republic in various climatic and soil conditions shows that the creation of irrigation systems of this type is effective and economically profitable when irrigation of various perennial plantations, vegetable, tilled crops, ornamental plantations, nurseries etc. Drip irrigation has almost universal application, in particular, it is applicable where other methods of irrigation can not be used or ineffective:
 
 With a complex relief and a large slope of the site (up to 45 degrees or more);
 In areas with prolonged droughts and constant strong winds;
 For local water sources with a relatively limited amount of water;
 On soils with low power and very low or high hygroscopicity;
 On soils prone to salinity;
 When used for irrigation of water with a high content of water-soluble salts, etc.

About salt fractionation in the process of terrigenous aerosol generation

The content of water-soluble salts in samples of surface soils from arid regions and separated from them fraction <0.1 mm was analyzed. Existence of salt fractionation in the aleurite was shown. The fractionation coefficients, defined as the ratio of ions concentrations in the water extracts from fraction <0.1 mm and soil as a whole, are arranged in the successions: Na > K > Mg > Ca and SO4 > HCO3 > Cl. It was found that the fractionation of salts depends on their solubility: than solubility below, that enrichment of soils fine fraction is more.

Experimental study of paint coatings resistance to osmotic destruction depending on water-soluble salts content on a metal surface

The main purpose of this work is to assess the relevance of the requirements for the quantitative content of water-soluble salts on the metal surface before applying an anti-corrosion coating. To do this, a series of tests are carried out by coating the metal surface of samples with different salt content, followed by aging in distilled water at high temperature and pressure. After exposure, the defects will be analyzed. The results obtained will help to choose the maximum allowable amount of soluble salts on the metal surface, because the internal coating of field pipelines is practically beyond repair, and to fix this value in the regulatory document.

The Effect of Rice Straw Gasification Temperature on the Release and Occurrence Modes of Na and K in a Fluidized Bed

Rice straw gasification was carried out in a laboratory fluidized bed reactor system from 600 to 800 °C in order to well-understand the release and occurrence mode of alkali metals as a function of temperature during the gasification process. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was applied to analyze the original rice straw and obtained fly ash at different temperatures. The results show that the Water-Soluble, Ammonium acetate-Soluble, Hydrochloric acid-Soluble, and Aluminosilicate Combination-Soluble modes of the Na and K contents in rice straw decreased in sequence. The content of Water-Soluble salts of Na and K accounts for more than 50%, while the content of the Aluminosilicate Combination-Soluble mode is the lowest: less than 5%. The release rate of Na appears to be consistent but nonlinear, increasing with gasification conversion ranges between 50.2% and 70.8%, from which we can deduce that temperature is not the only factor that impacts Na emission. The release of K can be divided into two stages at 700 °C. At the first stage, the release rate of K is almost invariable, ranging from 23.3% to 26%. At the second stage, the release rate increases sharply: up to 55.9%. The concentration and the proportion of the Water-Soluble, Ammonium acetate-Soluble, and Hydrochloric acid-Soluble modes of Na in fly ash decrease with a temperature increase. The release of K can be explained as follows: one path is an organic form of K converted into its gaseous phase; the other path is a soluble inorganic form of K that is volatile at a high temperature. With a temperature increase, the Aluminosilicate Combination-Soluble mode of both Na and K increases.

控盐施肥对滨海中度盐渍土壤盐分、养分及冬小麦产量的影响

以田间试验方法研究了两种控盐施肥模式对滨海引黄灌区中度盐渍土土壤养分、盐分和作物产量的影响。结果表明，常量化肥 + 有机肥模式(化肥N-P2O5-K2O：278.4-98.55-180 kg/hm2，有机肥3600 kg/hm2)与习惯施肥模式(化肥N-P2O5-K2O：274.2-345-0 kg/hm2)相比使返青期土壤水溶性盐分含量降低16.5%，全生育期土壤碱解氮含量平均提高3.8%，速效钾含量平均提高15.7%，有效磷含量未出现明显降低，冬小麦产量提高29.03%；减量化肥 + 增量有机肥模式(化肥N-P2O5-K2O：185.6-65.7-120 kg/hm2，有机肥7200 kg/hm2)与习惯施肥模式相比，能显著降低中度盐渍土中的水溶性盐含量(返青期可减少18.3%，平均减少12.6%) (P < 0.05)，同时未造成土壤有效养分含量的降低和冬小麦产量的下降。施用有机肥能够有效降低中度盐渍土土壤容重(平均降低1.8%)，增加土壤有机质(平均增加5.8%)，减缓有效磷、速效钾损失，是减少土壤盐分、改善土壤结构、改良滨海盐渍土的有效措施。 Using the method of field experiment, this study compared the amounts of soil nutrients, soil sa-linity and crop yields in Binhai saline-alkali soil under two kinds of salt-controlled fertilizer management models. The results showed that compared with the farmer’s practice model (chemical N-P2O5-K2O: 274.2-345-0 kg/hm2), the normal chemical fertilizer + organic fertilizer model (chemical N-P2O5-K2O: 278.4-98.55-180 kg/hm2, organic fertilizer 3600 kg/hm2) reduced the water-soluble salt content of seedling period by 16.5%, and increased the amounts of available N and K by 3.8% and 15.7% respectively in the whole growth period. There was no significant change in soil available P content under the condition of decreasing the amount of P fertilizer application. The winter wheat yields increased 29.03%. Compared with farmer’s practice model, the reduced chemical fertilizer + increased organic fertilizer model (chemical N-P2O5-K2O: 185.6-65.7-120 kg/hm2, organic fertilizer 7200 kg/hm2) could significantly (P < 0.05) reduce the amounts of water soluble salt (the period of seedling establishment decreased 18.3%, average decreased 12.6%) but maintain the amounts of soil available nutrient and winter wheat yields. Organic fertilizer application significantly decreased soil bulk density (the soil bulk density decreased 1.8%), increased the soil organic matter (SOM increased 5.8%), and reduced the loss of available P and K, indicating it is an effective measure to reduce soil salt and improve saline soil.

Dynamics of mine rocks and artificial soils physical and chemical characteristics under the impact of long-term reclamation

The physicochemical characteristics of mine rocks and artificial soils of forest recultivation plot № 1 of «Pavlogradska» main were studied. The absorbed moisture, maximal absorbed moisture, volume weight, unit weight, porosity of soils, content of water-soluble elements, pH of soils’ solutions, salinity and wilting point of plants were described. The dynamics of mine rocks and artificial soils physicochemical characteristics, which have an influence on forests suitability and silvicultural effect, gradually changing due to long-term reclamation, were ascertained. Variants of artificial soils, created on the experimental forest recultivation plot, have qualitative differences from natural etalon soils, disturbed destructive soils and differences between themselves. During the creation of various soil constructioins at the technical stage of recultivation it is often not taken into account the possible distant consequences that arise in connection with the dynamic features of the climate, topography, lithology, hydrology and other indicators of technogenic landscapes. Due to the functioning of these soil constructions on the biological stage of recultivation there are significant changes in physical properties and processes, occurring in the remediation root layer, therefore the monitoring of pedogenesis and evolution of these structures becomes relevant. Tehnozems, formed during reclamation process, are significantly different from zonal soils in the level of fertility (trophicity), physical, water-physical, agrochemical and other important ecosystem indicators. Spatial variability of artificial soils properties leads to a diversity of ecological conditions of mikrobocenosis, phytocenosis and zoocenosis functioning on the recultivation plots. The most important properties for evaluation of the prospects of ways and methods of mine dumps forest reclamation are the following physico-chemical parameters of mine rock and artificial soils as the actual acidity, content of water-soluble salts and humus, fraction composition of the clay fraction, mechanical (granulometric) composition, water-physical properties within a recultivation layer. The aim of the research is investigation of the dynamics of physico-chemical properties and forests suitability of bulk substrates on the forest recultivation plot № 1 of «Pavlogradska» main, with area of 3.2 hectares, where different constructions of forest plantations are being tested since 1976 on the different versions of artificial soils. The novelty of the work is that the findings substantiate the environmental assessment of artificial soils properties dynamics under influence of the long-term biological remediation. Over a long period of reclamation an acidity of main rock remains exceeding because of high sulphates content (up to 3,1 %). Salinity of substrates, contacting with main rock, decreased by 14–22 % in comparison with an initial salinity due to water-soluble salts migration and reclamation influence of experimental forest cultures. Bulk soil constructions on mine dumps of the forest recultivation plot in the steppe conditions can be attributed to humus-accumulative tehnozems with gradually increasing silvicultural effect.

Agrogenic transformation of the common black soil under long-term irrigation with mineralized waters

We studied the influence of irrigation with saline water on the properties of ordinary chernozem depending on the duration of irrigation. An increase of the degree of adverse changes in the physical, physical-chemical, chemical and biological properties of the soil accordingly increasing duration of irrigation is shown. The processes of salinization, alkalinization and soil compaction enhance mineralogy and grain size distribution of soil changes. Irrigation with saline water for 20 years has led to an increase in the total content of water-soluble salts in soil’s layer 0–25 cm from 0.07% to 0.14%. After 50 years of irrigation salts concentration increased to 0.23%. Density of subsoil increased from 1.23 g/cm3 to 1.43 g/cm3 . Long-term irrigation with saline water has adverse effect not only on chemical and physical properties of ordinary chernozem but also on the size and functioning of the soil microbial cenosis and soil enzymatic activity. Irrigation with saline water for 20 years in the vegetable and fodder crop rotation resulted in a decrease in the number of microorganisms by 16–37 %, irrigation for a period of 50 years has reduced the number of microorganisms belonging to main ecological and functional groups by 26–47%.

Effect of the soil treated with biochar on the rye-grass in laboratory experiment

Abstract The application of biochars to improve soils and to mitigate global climate change is a popular research area all over the world, although it is not a new topic. In our study, wood chips char (BC) and animal bone char (ABC) were applied. The pot experiments were conducted under laboratory conditions. 2 grams of rye-grass (Lolium perenne) were seeded into each pot. The following various soil parameters were measured: pH (KCl), AL-P2O5, AL-K2O, total water soluble salt content and organic matter content. The measured parameters from the plant samples were: total-P, total-K and micronutrients. Results show that the negative or positive effect of pyrolysis solids cannot be determined clearly, further experiments are needed.

Development of durable cementitious composites using sisal and flax fabrics for reinforcement of masonry structures

Natural fibres are one of the most studied materials. However, the use of these fibres as reinforcements in composite materials for structural applications, especially for existing or historical masonry structures, remains a challenge. In this study, efforts were made to develop sustainable composites using cementitious matrices reinforced with untreated bi-directional fabrics of natural fibres, namely, flax and sisal fibres. The fibres were mechanically characterised by tensile tests performed on both single yarns and fabric strips. Ageing effects due to fibre mineralisation in alkaline cement paste environments may cause a reduction in the tensile strength of natural fibres. The matrices used to study fibre durability were a natural hydraulic lime-based mortar (NLM) mix with a low content of water-soluble salts and a lime-based grouting (NLG) mix containing natural pozzolans and carbonated filler. Tensile tests on impregnated single yarns subjected to wetting and drying cycles by exposure to external weathering were conducted at different ages to quantify these problems. Composite specimens were manufactured by the hand lay-up moulding technique using untreated fibre strips and an NLG matrix. The mechanical response of natural fibre reinforced cementitious (NFRC) composites was measured under tension, and the effect of the matrix thickness was also addressed. Both sisal and flax fibres showed good adhesion with the NLG matrix, making them capable of producing composites with ductile behaviour and suitable mechanical performance for strengthening applications in masonry structures.

Energy crops on less favoured (alkaline) soil

The reduction in fossil energy and row material sources induces growing demand for renewable resources. The growing demand for herbal raw materials has land use impacts as well. One way to reduce the conflict between the food and energy crops can be the utilization of less favored areas by growing energy crops. Among the potentially available areas for this purpose the salt affected soils (SAS) occupy a significant territories. SAS with structural B-horizon (meadow solonetz soils) represent the most wide spread group of SAS in Hungary. About half of these soils have been reclaimed and used as arable land and the remaining 50% are used as grassland. Sweet sorghum production for manufacturing of alcohol production was investigated in a long term amelioration and fertilization experiment on a salt affected soil (meadow solonetz). By means of regression analyzes the effect of sodium content of the soil and increasing mineral fertilizer doses were studied. According to the multiple regression analysis only the effect of nitrogen fertilizer was significant. On the solonetz type salt affected soil the effect of water soluble salt content of the soil was not significant, but there was a closer correlation between the ammonium-lactate sodium content and the yield of sweet sorghum. The maximum green mass was 45–50 t ha-1, in the case of low Na content and high level of nitrogen fertilization.&#x0D; In order to quantify the potential yield of natural grass vegetation the relationship between the soil forming processes and the grass vegetationwas investigated. Beyond the different forms of Na-accumulation, the spatial pattern (mosaic-like characteristic) is also an inseparable feature of salt affected soils. The difference in the water regime, caused by the micro-relief is the main cause of variability. The run-on water keeps the deeper parts of the catena position wet longer. The wet situation causes more intensive leaching. In the low-laying parts of salt affected soils species preferring wet situations (mainly Alopecurus pratensis) are in majority. On the higher parts of the micro-relief species tolerating dry situations (mainly Festuca pseudovina) are dominant. The yearly grass production of low laying areas can be 4–7 t ha-1 but because of prolonged wet conditions the grass is not grazed and mowing can only be in old state. This old grass is not proper for feeding, but it may be suitable as energy plant.

Environmental and Mineralogical Studies of the Sabkhas Soil at Ismailia—Suez Roadbed, Southern of Suez Canal District, Egypt

Eight surface sabkha soils samples were collected from Ismailia—Suez roadbed, southwestern of Suez Canal district. Sedimentological and mineralogical analyses were conducted using grain size; X-ray diffraction and Scanning Electron Microscopy (SEM). Grain size analysis indicates high contents of fine sand and mud as well as presence of salts. X-ray diffraction; Scanning Electron Microscopy (SEM) and EDAX tool clarified that the sabkha soils are enriched by quartz, sulfate minerals (gypsum, anhydrite), carbonate minerals (calcite-dolomite-aragonite), chlorides (halite and bischofite), and clay minerals. The results elucidate that the appearance of sabkha deposits and their distribution in the study area are controlled mainly by the content of water soluble salts through parent materials; ground water table; subsurface structural; and physiographic features for instance surface relief or topography; and human activity.

Test Method for Determining the Efflorescence Potential of Masonry Materials Based on Soluble Salt Content

Abstract A single test method that is capable of determining the efflorescence potential for all materials in a masonry system is needed. The need for preconstruction testing is referenced in ASTM C1400-1—“Standard Guide for Reduction of Efflorescence Potential in New Masonry Walls”—but the standard acknowledges that there is not a suitable test method for all masonry materials. In the past, soluble salt measurements have been used to quantitatively access the efflorescence potential of masonry materials. To determine the water-soluble salt content of masonry materials, a simple leaching procedure was developed to remove the salts followed by quantification of the water-soluble salt content by ion chromatography. A series of modified efflorescence tests using salt solutions and real masonry materials has been used to determine the significance of water-soluble salt measurements. A clear threshold for soluble sulfate content that indicates a high potential for the development of visible efflorescence has been identified. Sulfate salts are the most common water-soluble compounds associated with efflorescence complaints.

Environmental Effect of Reservoirs Accumulating Highly Mineralized Oil-Field Waste Waters

The effect of oilfield waste water on the ground, the soil and the underground water has been studied. The reservoir is shown to be the source of environmental pollution due to the seepage of highly mineralized waste water through the reservoir bed and walls. Increased water mineralization in the spring two kilometers downward from the reservoir is one indication of it. Desalinization of the water should be expected in 140 years’ time. Typical chernozem formed on the area under study 40 years after the contamination have be-come naturally desalinized and desolonized as a result of a washing water regime and a genetically high content of carbonates and gypsum in the profile and soil forming rocks. Moreover, they retain an increased content of water-soluble salts, exchangeable sodium and electrical resistance, which is typical for alkali soils and solonetzs. The humus accumulative horizons show hydrophobic behavior. Due to leaching carbonates content, cation exchange capacity, mobile nitrogen and phosphorus availability decrease. Soil contamination by OWW leads to the accumulation of toxic elements in the soil and vegetation.

Application of MSWI fly ash on acid soil and its effect on the environment

This study evaluated the feasibility of using municipal solid waste incinerator (MSWI) fly ash as acid soil amendment. In particular, changes in soil physicochemical properties and the potential environmental problems caused by the application of MSWI fly ash were investigated. The results showed that application of MSWI fly ash to the acid soil could raise the soil pH. The contents of rapidly available P and K, and slowly available K in the amended soil had a linear relationship with the addition ratio of MSWI fly ash. An addition of less than 20% of MSWI could raise the soil respiratory intensity after incubation for 3-5 days. Application of MSWI fly ash to the soil increased its content of water soluble salts and heavy metals, which could cause phytotoxicity in the plants. Therefore, the addition of MSWI fly ash to the soil should not be excessive, and less than 5-10% is an advisable addition level depending on the acidity of the soil and the plants growing on it.

Change in technological properties of technogenic sulfide-contained raw material in the storage process

Results of modeling of changes in technological properties of sulfide minerals (pyrrhotite, pentlandite, and chalcopyrite) present in mining-industrial wastes stored in a climate in which evaporation prevails over precipitation are reported. It is proved that flotation activity of chalcopyrite and, in particular, of pentlandite diminishes, pyrrhotite increases, and selectivity and flotation of combined sulfides with respect to other minerals increases insignificantly. The content of water-soluble salts, dominated by nickel sulfates, increases with storage time.

Evaluation of Egyptian kaolin as a filler and extender pigment

Evaluation of Egyptian kaolin as a filler and extender pigment was carried out by measuring moisture content, water soluble salt content, hydrogen ion concentration, specific gravity, bulking value, oil absorption, acid and alkali resistance, particle size distribution and particle shape, and comparing it with a commercial imported sample. X‐ray and chemical analysis were used for the identification of the pigments. It was found that it is economical to use the Egyptian kaolin for it as a natural white fine mineral that is available in quantity in a relatively pure state. The physical and chemical properties peculiar to Egyptian kaolin make it an ideal choice as a filler and extender pigment, this is in comparison with the commercial imported sample.

Collapse deformations of gypsum sands

Gypsum silty sands with water-saturation under loading acquire collapsibility properties, whose magnitude depends on the water content, the dry density, the content of water-soluble salts, and the pressure. For sands containing highly soluble salts and gypsum, eSl varies from 0.004 to 0.16, and for sands containing highly soluble salts amounting to 2.5–2.7%, eSl=0.002–0.10. For w0>0.1, gypsum silty sands are practically noncollapsible.

Automated system for mechanical testing of soil specimens

Gypsum silty sands with water-saturation under loading acquire collapsibility properties, whose magnitude depends on the water content, the dry density, the content of water-soluble salts, and the pressure. For sands containing highly soluble salts and gypsum, gs£ varies from 0.004 to 0.16, and for sands containing highly soluble salts amounting to 2.5-2.7%, es£= 0.002-0.10. For w 0 > 0.i, gypsum silty sands are practically noncollapsible.