Influence of Conventional and Non-conventional Organic Sources of Plant Nutrients and Industrial Refuse for Yield and Quality Enhancement of Radish

Background: India generates about 50 million tons of municipal solid wastes (MSW) every year. Composting MSW is viewed as a low-cost method of diverting organic wastes from landfills in to a valuable product of agricultural importance. Farm Yard Manure (FYM) is an organic matter rich with a small quantity of nitrogen, while rice hull ash is a good source of plant nutrients particularly of potash. Bagasse ash is a waste obtained from sugar industries and is capable of supplying significant amount of plant nutrients. The present investigation aimed to study the effect of organic sources of plant nutrients and industrial waste on yield and quality of radish as a supplementary source of plant nutrients.Methods: A pot trial investigation was carried out during 2019 at Annamalai University, Chidambaram, Tami Nadu to study the influence of conventional and non-conventional organic sources of plant nutrients and industrial refuse on yield and quality of radish. Under this trial, FYM (12.5 t ha-1), Municipal Solid Waste Compost (25 t ha-1), Rice hull ash (5 t ha-1), Bagasse ash (10 t ha-1) with 100% RDF and 75% RDF were tried.Result: The present investigation under pot trial showed that the maximum radish root yield, shoot yield and quality were observed due to the application of organic sources of plant nutrients of both conventional and non-conventional organic sources and industrial refuse.

GEOPOLYMERS SYNTHESIZED FROM PHILIPPINE COAL ASH AS SUSTAINABLE ALTERNATIVE LOW HEAT TRANSMISSION AND FIRE-RESISTANT MATERIAL FOR BUILDINGS

Geopolymers are formed from alumina and silica rich materials by alkali dissolution and subsequent polycondensation into a polymeric network. Geopolymerization technology presents a great potential for positive environmental impact since many alumina- and silica- rich industrial waste materials, such as coal ashes, blast furnace slags, mine tailings, etc., can be used as its precursor materials in a process that requires less energy and gives up less emissions vis-à-vis the current conventional OPC (ordinary Portland cement) technology. In this study, geopolymer samples were prepared using an 85% coal fly ash (CFA) - 10% coal bottom ash (CBA) - 5% rice hull ash (RHA) wt/wt mix proportion and activated using an alkali solution of NaOH-Na2SiO3 at an 80%-20% wt/wt solid-to-liquid ratio. With this mix proportion, two types of specimens were used, a slab type with 50 mm thickness, and a cube type, 50 mm x 50 mm x 50 mm. The slab type specimens were used for evaluating fire resistance using ASTM E119, Standard Test Methods for Fire Tests of Building Construction and Materials, and the cube type specimens were used to study the effect of foaming agents on the strength and thermal conductivity of the geopolymers formed. Two types of foaming agents, hydrogen peroxide and sodium perborate, at an amount of 0.1% to 0.4% of dry mass mixture, were used. Results from the foamed geopolymers gave compressive strength values ranging from 0.37 to 0.71 MPa and densities of 1430-1560 kg/m3 at 0.3% to 0.4% peroxide added. Values of thermal conductivity of the foamed geopolymers were within 0.033-0.037 W/m-K for all foamed geopolymer samples tested which is a significant reduction compared to the thermal conductivity of the unfoamed geopolymer sample at 0.48 W/m-K. The fire resistance tests show that the unfoamed geopolymer samples perform better than OPC concrete. However, the foamed geopolymers have very low strength compared to the unfoamed sample compressive strength of 18.1 MPa and, thus, are suitable for non-load bearing, insulation applications.

INFLUENCE OF CONVENTIONAL AND NON-CONVENTIONAL ORGANIC SOURCES AND INDUSTRIAL REFUSE FOR YIELD AND QUALITY ATTRIBUTES OF RADISH

Radish is a unique root vegetable cultivated in India for its tender roots, consumed as a salad or cooked vegetable. The soil was collected from Vallampadugai, Chidambaram taluk farmer’s field having sandy loam soil texture, pH 7.0, EC 1.37 dSm-1, (textural class: Typic ustifluvents). A pot experiment was executed out in the pot culture yard of Annamalai University. Organic sources viz., FYM (12.5 and 25 t ha-1), non-conventional organic sources viz., household solid waste compost (12.5 and 25 t ha-1) and industrial refuse viz., rice hull ash (5 and 10 t ha -1) and bagasse ash (5 and 10 t ha-1) with 100% RDF and 75% RDF. There were 9 treatment combinations replicated thrice in CRD. The results showed that maximum root yield (845.9g pot-1) and shoot yield (501.9 g pot -1) were recorded in treatment, receiving 75% RDF + FYM @ 25 t ha-1 (T5). The highest chlorophyll content (1.38 mg g-1), total carbohydrates (4.76%), ascorbic acid (15.9 mg kg-1), and crude protein (0.85%) were registered in T5 (75% RDF+FYM @ 25 t ha-1)

Effect of Mixed Foundry Sand and Rice Hull Ash on the Mechanical Properties of Concrete

Waste foundry sand is the by-product of metal casting industry. Rice hull which is often burned after it is removed from rice is also a by-product of the agriculture industry. Disposing of these wastes leads to the environmental pollution. To optimal use of these wastes and avoid the adverse effects of dumping them, regular sand has been partially replaced with the waste foundry sand and rice hull ash pozzolan has been also used as a partial replacement for cement in making concrete. XRF, XRD and SEM experiments, compressive strength, tensile strength (Brazilian), flexural strength, modulus of elasticity and water absorption tests have been conducted. The results showed a slight decrease in compressive strength of samples in which regular sand was replaced with waste foundry sand by 15 percent; however, adding the rice hull ash to this mixture led to make a concrete comparable with control one. Also, using foundry sand in mix designs affects their physical performance. Moreover, the use of waste foundry sand in concrete is both economically and environmentally suitable.

Adjusting SiO2 : C mole ratios in rice hull ash (RHA) to control carbothermal reduction to nanostructured SiC, Si3N4 or Si2N2O composites

SiO2 : C mole ratios in RHA are controlled using an unconventional method, by which nanocomposites are synthesized via carbothermal reduction exploiting the intrinsic nanoscale SiO2 and carbon with no need for adding an external carbon source.

Mechanical Properties of Recycled Polypropylene Macro Flat Fiber Reinforced Concrete with Rice Hull Ash as Partial Replacement to Cement

Due to urbanization, the use of concrete in construction and waste production are arising that resulted to negative impact in environment. There are several studies utilizing cementitious material as substitute to cement and plastic waste as additive to concrete which has potential in increasing the strength. This study utilized recycled polypropylene macro fiber (RPPMF) as a reinforcement and rice hull ash (RHA) as substitute to cement. Varying percentage of RHA (10%, 15%, and 20%) and RPPMF (0.5%, 0.75%, and 1.0%) were incorporated in the concrete mix. Compressive and flexural strength results showed that the combination of RHA and RPPMF has a significant effect in the strength of concrete. Based from the results, the concrete with 10% replacement of RHA and 0.5% addition of RPPMF is theoptimum which has the highest compressive strength of 19.47 MPa with an increase of 13.40%, and a maximum flexural strength test of 3.7 MPa with an increase of 18.62%. Furthermore, the concrete with 10% replacement of RHA for both with additive of 0.75% and 1% RPPMF also attained higher flexural strength than of normal mix with 18.07% and 3.45% increase, respectively. It can be recommended to use for basement foundation walls and slabs, walks, patios, steps, and stairs. Also, it can be used for street roads because it reaches the standard strength of normal mix concrete and lessen the cracks due to addition of RPPMF.