Synthesis of Zeolite from Fly Ash and their Use as Soil Amendment

The amendments may be natural or synthetic and by their origin organic or inorganic. Among amendments, the inorganic ones are recommended, such as gypsum, lime, zeolites and altered rocks, including sand, ceramic, perlite, ash, slag, zeolite, pyrites, dolomite, calcined clay, etc. Fly ash-based zeolites can be used as amendments to improve the use of the soil for agricultural purposes. Generally, there are different methods for the synthesis of new materials using solid waste – fly ashes. Methods are known to be composed of a single stage or two stages. The first method – the conventional – is direct hydrothermal conversion of the mixture of ash and alkaline solution (NaOH or KOH), but only 50% of ashes can be converted into zeolite. The second method consists in mixing the ash with KOH and fusion at elevated temperature. The method leads to an advanced conversion – the type of zeolite depending on treatment conditions. Other studies recommend the conversion of ash using microwave ovens or ultrasound bath; in this case, the conversion time is reduced to 1–2 hours. From these methods, the direct method was proposed to be used in synthesizing zeolites for agriculture, with a part in controlling release of fertilizers and as a soil amendment. The synthesized materials were characterized with respect to microstructure (electronic microscopy SEM) and chemical and mineralogical composition (EDAX, X-ray diffraction). By analyzing the obtained data, one may observe the destruction of the ash network and crystallization of the zeolitic phase, especially in the case of treatment by diffusion. The XRD analysis confirms the presence of zeolite in materials obtained. Good results were also obtained in the case of using ultrasound treatment for zeolite synthesis; also, the time of treatment significantly decreased in this case

Updating of the cartographic database of the administrative territorial - units from the surface drainage and underground pipe drainage systems

The natural conditions from the extra Carpathian region of Suceava County have favored the humidity excess at the surface of the agricultural fields and in the superficial layers of the soil profile. In order to eliminate the water excess from the natural field-soil units the following systems have been created: surface drainage, underground drainage, ridged rows, deep harrowing. In the Suceava Plateau, with the following sub-units: Baia Depression, Falticeni Plateau, Dragomirnei Plateau and Radauti. Depression have been created more than 20 large hydroameliorative systems and a series of local systems for regulating the water regime in the soil and for effectively using the land resources. The case study included the framing of Suceava County in cadastral maps, scale 1: 50,000. Based on these geospatial data the land boundaries of the Baia - Sasca surface draining and underground draining system have been drawn up on 28 trapeziums, scale 1:5,000. The hydrotechnical scheme of the Baia - Sasca hydroameliorative system has been created between 1978 and 1980 on a total surface of 5,500 ha. The territorial distribution of the hydroameliortive system included the following five territorial - administrative units of the communes: Horodniceni, Cornu Luncii, Radaseni, Baia and Vadu Moldovei. The updating of the cartographic database was made using the coordinates system of the 1970 Stereographic projection for the 28 geodetic trapeziums at scale 1:5,000 that rigorously framed the hydroameliorative system studied, which represents the graphic support of the cadastral records of the land surfaces officially registered in the land register.

Biomass and biological fuels

The analysis of results obtained at national and international level on the utilization of renewable energy sources pointed out the opportunity of over-passing the energy crisis by the orientation of world economy to produce energy by the help of biomass. The high plant mass volume present in the world could compensate the relatively low output of light energy conversion through photosynthesis. The climatic conditions from Romania favourable to plant growing with high capacity of biomass multiplication, as well as farming by-product, animal dejections, domestic garbage, can ensure the biogas necessary to cover a great percentage of the energy necessary for animal breeding farms or heating dwellings

Technical Efficiency of the Subsurface Drainage on Agricultural Lands in the Moldova River Meadow

This study aims to investigate the technical efficiency of different subsurface drainage variants, in terms of the depth of the tile drains, spacing between the drain lines, type and thickness of the drain + filter complex, and the improvement procedures. Within the four variants, the discharge rate of the soil moisture excess was studied. In variants A and D, the spacing between drains is 20 m, and in the variants B and E, the spacing is 15 m. The depth of the tile drains is 0.8 m in variants D and E and 1.0 m in variants A and B. In variant A, tile drainage was combined with land shaping in the bedding system with top of ridges and furrows. Soil moisture was determined on checkpoints placed on drain cross section, at 2 m from drain lines, and of the middle of the drain spacing. In the version with land shaping, the drain lines located under the furrows favor the excess moisture removal. A similar technical efficiency was recorded in unimproved variant but with spacing between drains of 15 m. Best efficiency at removing excess water was registered in variant of the filtering material from ballast associated with flax strains