Re–Refining of Used Lube Oils and Sustainability

As petroleum products continue to be an inseparable part of our lives, so does the waste that is generated from these products, the prominent among them being the used lubricating oil. However, research shows that more than half of the used lube oil can be converted back to usable lubricant through the process of re–refining. This can certainly reduce the amount of waste oil in the environment and the need of crude oil extraction to a certain extent. As there are various different methods of re–refining, this work focused specifically on the method used widely in India, i.e., Vacuum distillation with Clay treatment. In this paper, the sustainability of the re–refining process was checked using the green chemistry principles and overall material balance of the process. Based on the assumptions made for the material balance, nearly 69.92% of lube oil base stock was obtained along with 11.13% fuel by - product and 12.14% residue, both of which have varied uses in the industry, thus producing additional profit.

Optimization of Ionic Soil Stabilizer Dilution and Understanding the Mechanism in Red Clay Treatment

Due to the insufficient understanding of the mechanism for soil strengthening by using Ionic Soil Stabilizer (ISS), the application of ISS in soil treatment is limited. In this paper, red clay samples were treated by using ISS and the effects were examined by the Atterberg test and uniaxial pressure test. In order to understand the mechanism, ISS dilution-based seepage test and ξ-potential test have been carried out. The results show that the ISS-Water mixture of 1 : 200 was the most effective ratio to reduce the plasticity index. The measurements indicate the thickness of the pair-electricity layer of adjacent clay layers and the repulsion force among soil particles is reduced, which in turn enhances the attraction force of the clay layers. This process strengthens the connection among the soil particles and thus increases the strength of the soil as detected by the experimental tests.

Recycling of Spent Reverse Osmosis Membranes for the Second Use in Clarification of Wet-Process Phosphoric Acid

Various techniques have been used to “clean-up” industrial phosphoric acid: precipitation, flotation, activated charcoal or clay treatment. To address membrane processes potential in phosphoric acid clarification process, this study explores the advantage of membrane techniques as new route for phosphoric acid clarification in an eco-efficient way through the use of “regenerated spent membrane”. Regeneration of the spent membranes was performed on of 0.15 m2 active area regeneration. These membrane samples were used to study the phosphoric acid clarification at a laboratory scale. They were immersed in an oxidizer for at most seven days. The samples were characterized systematically before immersion in an oxidant media. In this study, the potential to regenerate spent membranes and application of this media to clarify the 29% P2O5 phosphoric acid was demonstrated. This study shows, by tests that the reverse osmosis (RO) membranes achieve an abatement of 70% and 65% for solids and organic materials, respectively. These positive results will pave the way for implementing these membranes phosphoric acid treatment process. Moreover, besides being economically advantageous, the use of the spent membrane is likely an environmentally friendly route (no waste, no organic solvent and effluent to be regenerated later on).

Research and Development of Natural Vegetable Insulating Oil Based on Jatropha curcas Seed Oil

Jatropha curcas is a natural non-food resource with high oil-content seeds, that has attracted worldwide attention as it is an ideal renewable resource for the production of biofuels. With the increasing use of vegetable insulating oil in related industries, it is valuable to develop the vegetable insulating oils from Jatropha curcas seed oil. This study explores how to use Jatropha curcas seed oil to prepare high-quality natural vegetable insulating oil. A six-step process is first established according to the optimization results of alkali refining, activated clay treatment and alumina treatment of Jatropha curcas seed oil, combined with cold treatment, water washing and high temperature decompression treatment. Physicochemical and electrical performance tests show that most of the properties of the prepared vegetable insulating oil are significantly improved compared with the original seed oil, and meet the standard requirements for vegetable insulating oil, especially with no sulfur corrosion, a breakdown voltage of 72 kV and an acid value (KOH, potassium hydroxide) of 0.012 mg/g.

Land Engineering Consolidates Degraded Sandy Land for Agricultural Development in the Largest Sandy Land of China

Sandification has become a major obstacle to China’s regional farmland protection, economic development, and ecological civilization construction. It is urgent to adopt advanced ideas and practical actions to reverse the sandy land. Structural consolidation theory was introduced to rehabilitate sandy land into farmland by soil body building, soil layer reconstruction, and soil quality improvement. A field experiment was conducted in Mu Us Sandy Land to explore the effects of blended guest materials (red clay and loess) with sand at four volume ratios (1:1, 1:2, 1:3 and 1:5) on crop yields, soil properties, and root growth. Red clay and loess significantly increased clay and silt contents and regulated the soil total nitrogen concentration and organic matter content during the critical growth stage of maize. Red clay and loess had a significant promotion of maize and soybean yields at a volume ratio of 1:3. The maximum potato yield was 42,501 and 37,332 kg ha−1 in red clay treatment at a volume ratio of 1:5 and in loess treatment at a volume ratio of 1:3, respectively. Lowest root biomass in surface soil and surface/subsoil root biomass ratio mediated maize growth in red clay treatment. Red clay was considered as the better material to rehabilitate sandy land and develop agriculture in the long-term according to the engineering costs and crop yields. Water sustainable utilization strategies and potential popularization areas of sandy land structural consolidation should be enhanced in the future.

Sandy land structural consolidation engineering drive modern agricultural development in China’s Mu Us Sandy Land

<p>Sandification has become a major obstacle to China’s regional farmland protection, economic development and ecological civilization construction. Sandy land consolidation technologies and sustainable utilization modes will provide farmland for modern agricultural development. We introduced structural consolidation theory to sandy land rehabilitation from the aspects of soil body building, soil layer reconstruction and soil quality improvement. Filed experiments were conducted in Mu Us Sand Land to explore the effects of dry mixtures of guest material (red clay and loess) and sand at four volume ratios (1:1, 1:2, 1:3 and 1:5) on crop yield, soil properties and maize root growth. Red clay treatments had higher sandy land structural consolidation engineering costs and crop yields than loess treatments. Red clay and loess had significant promotion of maize and soybean yields at volume ratios of 1:3. The maximum potato yield is 42501 kg ha<sup>-1</sup> and 37332 kg ha<sup>-1</sup> in red clay treatment at volume ratio of 1:5 and in loess treatment at volume ratio of 1:5, respectively. Red clay and loess significantly increased clay and silt ratio and regulated the soil total nitrogen concentration and soil organic matter content during the critical growth stage of maize. Lowest root biomass in surface soil and lowest surface/subsoil root biomass ratio mediated maize growth in red clay treatment at volume ratio of 1:3. Red clay can be used to consolidate sandy land and develop modern agriculture in the long-term according to the engineering costs and crop yields. Enhanced land productivity, increased land transfer rent and extra wage income provide a stainable and stable increase in households’ income for escaping from poverty. Spatial overlap between red clay with sandy land makes red clay as a new available material for sand land consolidation and utilization from China to global scale. China’s sandy land structural consolidation engineering and sustainable utilization practices will contribute prescriptions to global desertification fighting and rural poverty alleviation. Regional water resource carrying capacity evaluation should be emphasized before sandy land structural consolidation engineering popularization.</p>