Geothermal Energy Potential for Cooling/Heating Greenhouses in Hot Arid Regions

In arid regions, drastic seasonal variations in the climatic parameters are common; thus, a high potential of geothermal effects for heating/cooling applications is expected. However, such applications are very limited in these regions due to the lack of information about underground temperature profiles of the surface and shallow zones. Therefore, this study aims to (i) measure the underground temperature profile for one year to determine the optimum depth for burying EAHE pipes; (ii) examine the possibility of water vapour condensation occurring in the buried EAHE pipes, if the air let into the pipes was humid; and (iii) quantify the maximum cooling/heating capacity, if an EAHE was implemented. The results show that a 3-meter depth is optimal to bury EAHE pipes, where the ground temperature is 32 °C in the summer and 29 °C in the winter. These temperatures would provide a maximum cooling/heating capacity of 1000/890 MJ day−1 for each 1 m3 of humid air exhausted from a greenhouse. If the EAHE were to operate in a closed loop with a greenhouse, the condensation of water vapour in the EAHE pipes would be impossible during the cooling process. The results of this study are useful for designers using geothermal effects for indoor space cooling and heating in arid regions.

Mapping of shallow water bathymetry and reef geomorphology using Sentinel-2 satellite imagery in Genteng Besar and Genteng Kecil Island, Kepulauan Seribu

Information on seafloor characteristics is one of the essential variables in coastal management and marine ecosystems. Application methods in remote sensing technology to study about characteristics of shallow waters have continuously been done. This research consists of two parts: an estimation of depth using Sentinel 2B satellite imagery with the Lyzenga algorithm and geomorphological classification of the benthic area using the Benthic Terrain Modeler (BTM) approach. BTM is a method to analyze benthic habitat and shallow water geomorphology. Integrated Depth data were analyzed using BTM to obtain bathymetric position index (BPI), slope, and classification of reef geomorphological structures. The resulting BPI value range is directly proportional to the given spatial area (scale factor). The slope is ranged between 0.01° – 19.24°, while optimum depth estimation is applicable until 10-meter. The values of BPI and slope were used as variables to classify the geomorphology of shallow water benthic areas based on the previous classification dictionary. Six geomorphological classes resulting from this study are Back Reef, Deep Depression, Depression, Lower Bank Shelf, Mid-Slope Ridges, and Reef Crest.

Development of a control system to maintain steady transition boiling

Steady transition boiling offers opportunities to observe fluid behavior and to measure transient and local heat flux as the surface dries and wets. This report discusses temperature control in transition boiling. Each component in the control system is either measured or estimated, and the controller parameters are determined along with the optimum depth of the temperature feedback point. Experiments are performed to verify the theoretical stability limit.

Determination of the optimal transition point between a truck and shovel system and a semi-mobile in-pit crushing and conveying system

One of the most challenging aspects in semi-mobile in-pit crushing and conveying (SMIPCC) system design is determining the optimum depth at which to change from a purely truck-based haulage system to a conveyor-based haulage system. We used scenario analysis to determine the optimum transition depth between a truck and shovel (TS) system and a SMIPCC system. Traditional pit-limit algorithms were used to generate the final pit limit on a copper deposit, which was then divided into four pushbacks. The final operating pushbacks (phases) were designed for both TS and SMIPCC. The end depths for each phase are viewed as candidate transition points to switch from the TS to SMIPCC haulage system. Economic calculations were applied for five different scenarios, including adopting SMIPCC from the outset (pure SMIPCC), after the first, second, and third phases, and finally not using the SMIPCC system (pure TS) at all. The analysis indicates that the second scenario, at a depth of 335 m, results in the lowest cumulative discounted cost (CDC). In this case, the CDC is 17.6% lower than that for the pure TS scenario and 10.7% lower than for the pure SMIPCC system scenario.

Combatting lime kiln ringing problems at the Arauco Constitución mill

The lime kiln at the Arauco Constitución mill experienced severe ringing problems requiring it to be shut down for ring removal every 3 to 6 months. The mill controlled the problems by blasting ring deposits off during operation with its existing industrial shotgun and a newly installed Cardox liquid carbon dioxide (CO2) cartridge system. Various ring blasting procedures were tested to determine the optimum ring location and thickness to blast; the optimum depth to insert the CO2 cartridge into the kiln; and the most effective blasting frequency and sequence to employ. The best strategy was found to be the weekly blasting operation that alternated between the liquid CO2 cartridge and the industrial shotgun, with the CO2 cartridge inserted into the ring mass, 20 cm (8 in.) away from the refractory brick surface, and the shotgun aimed at rings at about 28 m (92 ft) from the kiln discharge end. With each blasting event removing considerably more rings than before, it takes a longer time for rings to rebuild, allowing the kiln to run continuously between annual maintenance shutdowns with only a few short (< 4 h) downtimes for ring removal. This substantially reduces the costs associated with ring removal and lime replacement during unscheduled shutdowns.

Integration of Satellite Image Derived Temperature and Water Depth for Assessing Fish Habitability in Dam Controlled Flood Plain Wetland

The present study attempted to investigate the changes in temperature conducive to fish habitability during the summer months in a hydrologically modified wetland following damming over a river. Satellite image-driven temperature and depth data calibrated with field data were used to analyse fish habitability and the presence of thermally optimum habitable zones in some fishes such as Labeo Rohita, Cirrhinus mrigala, Tilapia fish, Small shrimp, and Cat fishes. The study was conducted both at the water's surface and at the optimum depth of survival. It is very obvious from the analysis that a larger part of wetland has become an area that destroyed aquatic habitat during the post-dam period and existing wetlands have suffered significant shallowing of water depth. This has resulted in a shrinking of the thermally optimum area of fish survival in relation to surface water temperature (from 100.09 km2 to 74.24 km2 before the dam to 93.97 km2 to 0 km2 after the dam) and an improvement in the optimum habitable condition in the comfortable depth niche of survival. In the post-dam period, it increased from 75.49 % to 99.765%. Since the damming effect causes a 30.53 to 100% depletion of the optimum depth niche, improving the thermal environment has no effect on fish habitability. More water must be released from dams for restoration. Image-driven depth and temperature data calibrated with field information has been successfully applied in data sparse conditions, and it is further recommended in future work.

Technical solution for providing optimal seeding depth and improving the contact of small seed crops with wet soil when seeding

The article describes an invention that relates to agricultural machinery, namely to seeders for sowing grass seeds and grain crops, in areas with insufficient moisture and soils susceptible to wind erosion. The objective of the invention is to provide the optimum depth of seeding, in particular, of small-seeded crops and herbs, when sowing on treated and untreated backgrounds in soil-protective, minimal and “zero” tillage systems. The technical result of the invention lies in the fact that the distinguishing features of a grain-seeder seeder provide an optimal seeding depth and improved contact of small-seeded crops, in particular grass seeds with moist soil, when sowing in soil-protective, minimal and “zero” tillage systems. The proposed seeder, the coulters are rigidly connected to the frame by means of rods, which allows the coulters to withstand the same predetermined depth on soils of different hardness. The initial formation of sowing grooves is carried out installed before the coulters, in their longitudinal plane of symmetry, at an angle 55-65 degrees to the horizontal, revolving cutter knives with a wear-resistant coating of the working part. There are two packer roller rollers pivotally connected to the frame with a cylindrical rim, while the batteries are spring loaded with the ability to adjust the pressure of the rollers on the soil.

Effect of Depth of Sowing on Seed Germination and Seedling Vigour of Juniperus polycarpos C. Koch

The seeds of Juniperus polycarpos were sown at six different depths in the nursery viz., 0.5cm, 1.0cm, 1.5cm, 2.0cm, 2.5cm and 3.0cm to study their effect on germination and seedling vigour index. Significant differences were observed in germination percentage and seedling vigour index of Juniperus polycarpos seeds sown at different depth in the nursery. The maximum germination of 68.88 per cent was recorded in seeds sown at 1.5cm depth followed by 50.66 per cent germination recorded at 1.0cm depth, 42.00 per cent germination recorded at 0.5cm depth and 32.00 per cent germination recorded at 2.0cm depth. The minimum germination of 20.66 per cent was recorded in seeds sown at 3.0cm depth. Similarly, seeds sown at 1.50cm depth recorded maximum seedling vigour index (1377.38) followed by seeds sown at 1.0cm depth (1077.26) and then by seeds sown at 0.50cm depth (890.73). The seed sown at 3.0cm depth recorded minimum seedling vigour index (458.40). It is recommended that the seeds of Juniperus polycarpos should be sown at optimum depth of 1.50cm in the nursery for getting maximum germination and seedling vigour.

Research results of agrotechnical indicators of universal seed-fertilizer stubble drill SZS-4U

As known, seed drills are the most complex agricultural machines in terms of the performed technological process since they include a number of sequentially or concurrent operations. The modern crop farming technologies shall include practices that improve soil fertility through the application of organic and mineral fertilizers. Sustainable crop production is carried out with environmentally friendly and economically competitive farming methods. The object of this paper is to determine the main agrotechnical parameters of universal seed-fertilizer stubble drill SZS-4U. The research methodology has involved determination of the main agrotechnical parameters of the seeder. Based on the research results it was found that the uneven seeding of winter and spring wheat at two speed modes was 2,98% and 3,04%, for spring barley is was 2,70% and 3,00%, mineral fertilizers – 7,57% and 7,69%. With the optimum depth of the openers, the actual depth of seeds placement of spring wheat was 56,5 and 48,9 mm, winter wheat – 44,5 and 43,9 mm, spring barley – 48,0 and 44,3 mm, these data meets a given depth of seeding. After SZS-4U has passed there’s been retained 68,12 – 72,38 percent (%) of stubble on unprepared or minimally prepared grounds, and these values meet agrotechnical requirements which stipulate at least 65 ± 10%. Thus, we can conclude that the universal seed-fertilizer stubble drill SZS-4U meets all agrotechnical requirements and stipulated indicators in terms of sowing winter wheat, spring barley, and spring wheat with simultaneous fertilization.

Effect of Texture on Energy Consumption for High Frequency Hydraulic Impact Piston Pair

Limited by the influence of the traditional clearance seal structure on the leakage and friction loss of the piston pair, the energy utilization ratio of the hydraulic impactor is difficult to improve. As such, a novel clearance seal structure with cylindrical texture for the impact piston is proposed to solve it. Considering the leakage and friction loss of impact piston pair, an energy consumption evaluation index is put forward. Based on the average Reynolds equation, an energy consumption analysis model for a textured high-frequency hydraulic impact piston pair is established, and the influence of piston texture parameters for the YG45 hydraulic impactor on energy consumption under rated working conditions is studied. The results show that energy consumption of an impact piston pair accounts for 29.77% of total energy loss. The variation of area ratio textured makes the ratio of energy consumption to the piston pair decline 1.32%~10.98%, where the optimum area rate textured is 0.64 ~ 0.7. The variation of depth ratio textured leads to the reduction of the ratio of energy consumption to piston pair by 3.21% ~ 5.68%, where the optimum depth ratio textured is 1 ~ 1.1.The texture structure of the piston pair significantly reduces the energy consumption of the impact piston pair, and it is an effective approach to avoid the design dilemma for the conventional impact piston pair.