Scale Removal Research Articles

Ultrasound based technology for removal of scale from downhole production tubing, an experimental verification

Deposition and blockages due to scale formation inside the production tubing are the most common problems experienced during the production of oil and gas, and this significantly leads to a decline in the production rate. Progressive scale formation limits production which subsequently leads to abandonment of the well. There is a great cost attached to preventing the occurrence and remediation of scales. Chemical and mechanical techniques for scale removal in production tubing have drawbacks like environmental concerns, equipment damage, and incomplete removal of stubborn scale. In contrast, ultrasound-based methods offer potential benefits such as non-destructiveness, enhanced efficiency, reduced chemical usage, and increased safety for workers. Despite the extensive research about the application of ultrasound to improve oil recovery, there remains a significant gap in the comprehensive exploration of optimum ultrasound parameters (frequency, power, radiation time, interval time, and location) for the removal of in-situ built scales in a simulated production tubing under different flow rates. This study addresses this gap by investigating the impact of ultrasound parameters on its performance for removal of calcium carbonate (CaCO3) and gypsum scales in a simulated production tubing system under different flow rate (100% and 50%). The ultrasound parameters include frequency (in the range of 20 kHz–120 kHz), power (50 W and 100 W), operation time, and location (externally attached and inserted into the production tubing).Initial tests revealed that adjusting the operating frequency improves the impedance matching, resulting in enhanced scale removal. The experiments also explored the influence of flow rate on scale removal, showing a general increase in removal with higher flow rates, specially at operating frequencies 20 kHz and 28 kHz. It was also demonstrated that the higher frequencies of 40 kHz, 68 kHz, and 120 kHz exhibit limited removal efficiency. The effectiveness of scale removal exhibited nonlinear variation over time, with the 28 kHz, 100 W transducer demonstrating the most significant improvement.In-pipe ultrasonic rod, operating at a constant frequency of 26 kHz, was employed to assess its performance for scale removal. Pulsed treatment was introduced to manage rod heating issues. Results demonstrated that both interval times and flow rates influenced CaCO3 removal, with shorter intervals yielding better results. The ultrasonic rod's efficacy was also observed in removing gypsum scale layers, suggesting potential applications in treating scales with various strengths. The results of this study can contribute to a better understanding of how the frequency, power, operating time and interval, and flow rate influence ultrasonic scale removal. The experimental findings provide valuable insights in optimizing practical applications for removal of scales from production tubing.

Personal, financial and time burden in inherited ichthyoses: Asurvey of 144 patients in a university-based setting.

Patients with inherited ichthyosis suffer from scaling due to mutations affecting the epidermal barrier. Symptomatic treatment with ointments, bathing and mechanical scale removal can alleviate the disease, but therapy is time and cost intensive. We investigated costs, time and disease burden of ichthyoses. The study addresses difficulties of the healthcare situation for patients with ichthyoses and reveals potential improvements. We developed a questionnaire addressing time and financial effort for the treatment. Additionally, we collected data of the Dermatology Life Quality Index (DLQI) and the Pruritus Life Quality (5PLQ) questionnaires to determine the impact of ichthyosis and associated pruritus on quality of life (QoL). We recruited 144 patients with ichthyosis (median age: 23; 53.5% female) from the Department of Dermatology in Muenster (Germany) and the German patient support group including common, rare and syndromic subtypes. Eighty-seven percent reported applying topical therapeutics at least once per day, 66.4% several times with an overall median duration of 15 min. Highest single expenditure of time was due to balneotherapy (n = 115; median bathing time: 40 min). In 81.9%, the health insurance did not completely cover the costs for topical treatment causing additional financial burden to the patient with a median of 71 € per quarter, herein creams being the largest cost factor (50 €). Patients with Netherton syndrome showed the highest median expenditure (170 €). The QoL impairment under treatment was moderate (median DLQI: 8.5 points). Pruritus was prevalent in 79.9% and showed a distinct impact on QoL (median 5PLQ: 7.5 points) without any significant difference between the subtypes (p = 0.37). Patients suffering from ichthyoses have a large and lifelong overall burden in mild and severe subtypes. Since continuous topical treatment is required, financial and psychosocial support needs to be considered beyond dermatological care.

Research Progress on Novel Electrochemical Descaling Technology for Enhanced Hardness Ion Removal

In recent years, electrochemical descaling technology has gained widespread attention due to its environmental friendliness and ease of operation. However, its single-pass removal efficiency could be higher, severely limiting its practical application. To overcome the limitations of traditional electrochemical descaling processes, this paper first focuses on the separation efficiency of H+ and OH− in the scale removal process based on numerous recent research papers. It mainly emphasizes how innovative cathode design can enhance the efficiency and stability of electrochemical descaling. Furthermore, this paper explores the coupling of electrochemical processes with different water treatment technologies, such as the combination of electrodeposition with electrocoagulation, filtration crystallization, microfiltration, and electrodialysis, and how these methods synergistically enhance descaling effects. Additionally, this paper discusses potential future directions for electrochemical descaling technology, including innovations in scale expansion, material updates, process optimization, system integration, and automation. Finally, this paper analyzes the practical challenges of electrochemical descaling technology, such as cost, energy consumption, equipment durability, and environmental impact, and proposes solutions. The implementation of these strategies is expected to promote the commercialization of electrochemical descaling technology, making it more aligned with the sustainability requirements of industry and the environment.

DEVELOPMENT OF TEST BENCH FOR EVALUATION OF RESISTANCE OF INTERNAL PROTECTIVE TUBING COATINGS TO INORGANIC SALT DEPOSITS

The formation of inorganic deposits on the working surface of oil and gas equipment is one of the most common causes of failures in oil and gas fields. Inorganic salt deposits formed in tubing reduce pipeline throughput capacity and lead to equipment failure. Thus, the problem of salt formation in tubing is relevant and requires the search for optimal methods to solve it. There are a large number of methods aimed at preventing the formation of inorganic scale and at removing the resulting scale from tubing. The methods of removal of scale from the tubing are expensive, time-consuming, and they require a shutdown at the oil production facility. Therefore, it is preferable to use methods for preventing salt formation in tubing pipes.One of the methods for preventing salt formation in oil production is the use of internal protective coatings of the NKT. It is important to understand that the use of coatings to prevent salt formation is not a universal method, individual selection of the protective coating is required for each object. In addition, at the moment, the effectiveness of the use of protective coatings as a measure to prevent salt formation in the tubing has not been fully proven. The selection of an effective internal coating (to prevent salt formation on the surface of the equipment) using pilot field tests is an expensive and long procedure, so it is necessary to develop a laboratory method and specialized testing equipment to solve this problem. This paper reviewed the existing test equipment to assess its potential for laboratory dynamic testing of tubing coatings under saline conditions. Based on the advantages and disadvantages of existing equipment, the «Stand for assessing the resistance of coatings to inorganic salt deposits» was developed. This article describes the development of the «Test Bench for Evaluation of Coating Resistance to Inorganic Salt Deposits,» which can be used to assess the possibility of using protective tubing coatings to prevent the formation of inorganic salt deposits on the inner surface of pipes.

Electrochemical silica removal from carbon nanotube surfaces: Energy consumption and removal mechanisms

Inorganic fouling, or scaling, is a major challenge for engineered systems exposed to aqueous environments, particularly in water treatment, desalination, or thermal systems where the high salinity and temperature conditions favor surface scaling. Silica, in particular, is hard to remove once a scaling layer forms on the surface. Current scaling mitigation strategies include the addition of antiscalants, physical cleaning by flushing or backwashing, and pretreatment of the feed water. These mitigation strategies increase operation costs due to increased chemical use and system downtime, as well increase the complexity of the process. In this work, we investigated the ability of carbon nanotube (CNT) coatings to disperse silica from the surface via electrochemical reactions, providing a chemical-free approach to scaling control. Silica scaling was induced and then dispersed from CNT coupons upon the application of a potential difference across the experimental set up, with the CNT coupon acting as a cathode or anode. Scale removal was measured using optical coherence tomography at different applied current densities. In this study, a cathodic current of 2.5 A/m2 was found to achieve the highest silica removal: > 75% after 30 min. Control experiments conducted using pH-buffered solutions and pH-insensitive gypsum as the scaling mineral suggest that silica dispersion from the CNT surface was due to a combination of gas evolution and interfacial pH change. These results provide a better understanding of the potential of using electrochemical coatings for the removal of inorganic fouling from surfaces.

CHEMICAL REMOVAL OF IRON SULFIDE DEPOSIT IN PIPES FROM OIL AND SOUR GAS PRODUCTION

Hydrogen sulfide (H2S) and carbon dioxide (CO2) present in oil and natural gas cause mild steel corrosion, potentially resulting in formation of corrosion product layers on the internal surfaces of tubulars. In field experiences relating to the research reported herein, this has led to restrictions on the flow of water produced from a three-phase horizontal separator. This paper demonstrates a specific case of chemical removal of relatively hard, dark, and adherent heterogeneous deposits on the internal surface of the pipe. The phases involved in this process are iron sulfide, iron oxides and calcium carbonate existing as scales/corrosion products. To evaluate their dissolution, laboratory tests were conducted using hydrochloric acid (HCl) with additions of chlorine in the form of calcium hypochlorite [Ca(ClO)2]. Appropriate safety measures were taken employed, considering hazards associated with chlorine and toxicity of hydrogen sulfide. The treatment regime had 87 % effectiveness for scale removal in combination with propargyl alcohol (2-propyn-1-ol) as a corrosion inhibitor.

Effect of EDTA Addition on Acidizing Treatment Process

<p>Acidizing treatment is commonly used to solve scale problem on production equipment. In this process, Hydrochloric acid (HCl) is often used to treat CaCO<sub>3</sub> scale, posing the risk of pipe corrosion due to its high corrosive characteristics. Thus, the purpose of this study was to determine the impact of adding EDTA additive into HCl solution during the acidifying treatment procedure. The methodology included various stages such as scale identification, chemical scale removal test using 7.5% and 15% HCL solution, 15% HCl solution test with EDTA as an additive, and corrosion determination using corrosion coupon. The results showed that 15% HCl solution was very effective in removing CaCO<sub>3</sub> scale but had a high corrosion rate of 186.255 mpy. Furthermore, the addition of 10 mL EDTA solution as an additive removed scale and reduced corrosion rate by approximately 85%.</p>

Synthesis and evaluation of novel copper hydroxide-loaded SBA-15 as inhibitors for an oilfield carbonate scale control: an experiment and a model study

Abstract The oil and gas industry faces significant challenges in scaling, leading to financial losses and production decline. This study aims to synthesize solid-scale inhibitors using copper hydroxide-loaded SBA-15 catalysts for the scale removal. The catalysts were synthesized using a simple impregnation method, and characterized using various tests. To evaluate the scale inhibition efficiency, static scale inhibition tests are conducted, measuring the effectiveness of the synthesized inhibitors in preventing scale formation. The results show potential applications for copper hydroxide-loaded SBA-15 solid-scale inhibitors in the oil and gas industry. The inhibitor's efficiency increases under alkaline conditions, while its efficacy decreases with rising pH. At an optimal dosage of 7.5 ppm and temperature of 55 °C, the inhibitor achieves an impressive 99% inhibition efficiency on calcium carbonate, indicating excellent inhibitory performance. This material holds promise for more efficient and cost-effective scaling inhibition solutions across various industrial processes.

Preparation of barium sulfate chelating agent DTPA-5Na and molecular dynamics simulation of chelating mechanism.

Barium sulfate (BaSO4) scale is dense and hard, making it difficult to remove using conventional acid and alkali treatments. Diethylenetriaminepentaacetic acid (DTPA) and its complexes have been identified as important chelating agents for the removal of BaSO4 scale. However, DTPA has good solubility only under strong alkali conditions, which in turn exacerbate scaling. To improve the solubility and chelation effectiveness of DTPA, penta sodium diethylenetriamine-pentaacetate (DTPA-5Na) was synthesized using chloroacetic acid, diethylenetriamine, sodium carbonate, and sodium hydroxide as raw materials. The structure of DTPA-5Na was characterized by infrared spectroscopy and 1H-NMR, and its chelation effectiveness was evaluated. Experimentation demonstrated that under conditions of 50 °C and with a molar ratio of chloroacetic acid (ClCH2COOH), sodium carbonate (Na2CO3), sodium hydroxide (NaOH), and diethylenetriamine (DETA) of 5.00 : 2.50 : 5.25 : 1.00, the reaction for 6 hours resulted in the optimal chelation value of DTPA-5Na at 76.8 mg CaCO3·per g. Analysis of the chelation and dissolution of BaSO4 scale using DTPA-5Na and microstructural scanning electron microscopy of the BaSO4 crystal indicate that DTPA-5Na functions through solubilization, lattice distortion, and flaking dispersion to remove BaSO4. Molecular dynamics simulation software was used to simulate the chelation mechanism of DTPA-5Na, where the results indicated strong adsorption of DTPA-5Na to the surface of BaSO4. The adsorption energy follows the order of (120) surface > (001) surface > (100) surface > (210) surface. The adsorption is mainly a result of the interaction between the carboxylic "O" atom in DTPA-5Na and the (001), (100), and (120) surfaces of BaSO4 scale, while N atoms in DTPA-5Na structure primarily interact with the (210) surface. The adsorption of "O" atoms is stronger than that of "N" atoms in the DTPA-5Na structure.

Research on the descaling characteristics of a new electrochemical water treatment device.

In recent years, chemical water treatment equipment has gained significant attention due to its environmental-friendly features, multifunctionality, and broad applicability. Recognizing the limitations of existing chemical treatment equipment, such as challenges in scale removal and the high water content in scale deposits, we propose a novel drum design for both anode and cathode, enabling simultaneous scale suction and dehydration. We constructed a small experimental platform to validate the equipment's performance based on our model. Notably, under the optimal operating parameters, the hardness removal rate for circulating water falls within the range of 19.6-24.46%. Moreover, the scale accumulation rate per unit area and unit time reaches 13.7 g h-1 m-2. Additionally, the energy consumption per unit weight of the scale remains impressively low at 0.16 kWh g-1. Furthermore, the chemical oxygen demand (COD) concentration decreased from an initial 106.0 mg L-1 to a mere 18.8 mg L-1, resulting in a remarkable total removal rate of 82.26%. In conclusion, our innovative electrochemical water treatment equipment demonstrates exceptional performance in scale removal, organic matter degradation, and water resource conservation, offering valuable insights for future research and development in chemical treatment equipment and electrochemical theory.

Novel Environmentally Friendly Nanomaterials for Drag Reduction of the Emulsified Acid System.

Matrix acidizing is a technique that is widely used in the petroleum industry to remove scales and create channels in the rock. Removal of scales and creation of channels (wormhole) enhance productivity. Conventional acidizing fluids, such as hydrochloric acid (HCl) for carbonate and a mixture of hydrofluoric acid (HF) and HCl acid, are used for the matrix acidizing process. However, these fluids have some drawbacks, including strong acid strength, corrosion at high temperatures, and quick reactions with scale and particles. Emulsified acid systems (EASs) are used to address these drawbacks. EASs can create deeper and narrower wormholes by reducing the reaction rate of the acid due to the external oil phase. However, EASs have a much higher viscosity compared to conventional acidizing fluids. The high viscosity of EASs leads to a high drag that restricts pumping rates and consumes energy. This study aims to utilize environmentally friendly and widely available nanomaterials as drag-reducing agents (DRAs) of the EAS. The nanomaterials used in this study are carbon nanodots (CNDs). CNDs have unique properties and are used in diverse applications in different industries. The size of these CNDs is usually smaller than 10 nm. CNDs are characterized by their biocompatibility and chemical stability. This study investigates the use of CNDs as DRAs for EAS. Several experiments have been conducted to investigate the CNDs as a DRA for the EAS. The developed EAS was initially tested for conductivity and drop-test analysis to ensure the formation of an inverted emulsion. Thereafter, the thermal stability for the range of temperatures and the rheological properties of the EAS were evaluated to meet the criteria of field operation. Then flow experiments with EASs were conducted before and after adding the CNDs to investigate the efficacy of drag reduction of EASs. The results revealed that CNDs can be used as viscosity reducers for the EAS, where adding the CNDs to the EAS reduces the viscosity at two different HCl concentrations (15 and 20%). It reduces the viscosity of the EAS in the presence of corrosion inhibitors as well as other additives to the EAS, showing its compatibility with the field formulation. The drag reduction was observed at the range of temperatures investigated in the study. The conductivity, stability, and rheology experiments for the sample taken after the flow experiment are consistent, ensuring CNDs work as a DRA. The developed EAS with CNDs is robust in terms of field mixing procedures and thermally stable. The CNDs can be used as a DRA with EAS, which will reduce drag in pipes, increasing pumping rates and saving energy.

Synthesis, morphology and dye removal studies of ternary hydrogels bearing carboxymethyl cellulose, chitosan and glutamic acid

Ternary polysaccharide-based hydrogel of carboxymethyl cellulose (CMC) with chitosan (CHT) and L-Glutamic acid (GLU) was synthesized using ZnCl2 as a cross-linker. The feasibility of this ternary engineered hydrogel in removing the acidic dye (Methyl Orange) and basic dye (Amido Black-10B) by the adsorption process from contaminated water was explored. Initially binary blends of CMC and CHT were synthesized bearing different ratios to ascertain the best mixing ratio and subsequently from the best selected ratio (CC-1), another binary blend (CC-Z) was prepared by adding ZnCl2. Lastly, the ternary hydrogel was synthesized using CMC-CHT-GLU with and without chemical cross-linker abbreviated as CCG-Zn and CCG respectively. All four samples were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), powdered X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and UV-visible spectroscopy. Swelling properties of these hydrogels were studied in demineralised water (DMW), and CCG-Zn gave best results. Adsorption behaviour of CCG-Zn was analyzed in acidic, basic buffer and neutral solution to check its suitability towards different pH environments. Moreover, absorbance of dye-contaminated solutions (treated with CCG-Zn) was measured using UV-visible spectroscopy to determine the removal efficiency (R) and adsorption capacity (q) in mg/g. It was observed that CCG-Zn is suitable for efficient removal of basic dye from aqueous solution and this ternary hydrogel may be effectively used for the large scale removal of cationic impurities.

Research on the Model of Scale Removal under Slurry Impact Based on BP Neural Network

Research on the Model of Scale Removal under Slurry Impact Based on BP Neural Network

A Review on the Prospective Applications of Fungal Keratinases

Keratin is the most abundant insoluble protein in the epithelial cells of vertebrates and represents the major constituents of skin, hair, feathers, wool, and nails. It is among the hardest-to-degrade animal protein, the major component in poultry feathers. Keratinases are exciting proteolytic enzymes that display the capability to degrade the insoluble protein keratin, recalcitrance to common proteolytic enzymes like pepsin, trypsin, and papain. Keratinases are versatile enzymes gaining momentum in the field of Biotechnology with potential applications. As the keratin is too hard to degrade, substrates like hair, hoof, horn, feather nail etc. can be treated effectively with keratinases, which is considered as the remarkable application of the enzyme. The poultry feather degradation using keratinase improve the nutritional value of feather meal and can be applied for the production of rare amino acids like proline, cysteine, serine, and methionine. The potential use of these enzymes have been associated with cosmetic industry and acne treatment. The other applications of keratinase include the production of biofuel, detergent, films, coatings, glues and pesticidal toxins, degumming of silk, scale removal from wool fibre, degradation of prions etc. Keratinases are mainly produced by different microorganisms like fungi and bacteria which are considered as biodegradable, eco-friendly enzymes without any harmful effects like that of the chemical counterparts. As the separation of bacterial keratinase is a cost intensive process compared to fungal keratinase, the review is focussed on isolation, purification and prospective applications of fungal keratinase.

Field evaluation of organic and synthetic insecticides against the hala scale, Thysanococcus pandani (Hemiptera: Halimococcidae), on Maui, Hawaii.

The hala scale, Thysanococcus pandani Stickney, is an invasive insect that infests hala trees, Pandanus tectorius, and has recently arrived in the Hawaiian Islands of Maui, Oahu, and Molokai. Hala scale is native to Thailand, Indonesia, and Singapore and was accidentally introduced to Maui, with its first detection in Hana in 1995. The hala tree is a frequently planted ornamental plant throughout Hawaii's urban landscape and is also a native tree found in coastal areas of ecological suitability throughout the state. These trees are integral to native Hawaiian weaving traditions, as the leaves were used to make items such as sails, hats, or mats. The spread of T. pandani threatens the continuation of these practices, as the plant material may not be sufficient for weaving. Hala trees infested with T. pandani can have negative effects such as deformation, discoloration, and early tree death. Experimental field trials were set up to evaluate the efficacy of organic and chemical insecticides as potential treatments to mitigate the damage of T. pandani infestations. This was done on the Island of Maui, where T. pandani is widespread. These trees were artificially inoculated with T. pandani and evaluated throughout the trials for changes in plant height, canopy width, scale removal, and visual infestation ratings. The results of 2 repeated field trials indicated that flupyradifurone and buprofezin were effective treatments in the reduction of the hala scale infestation and improving visual aspects related to plant health.

Simulation Analysis and Optimization Design of Electromagnetic Fields in Coaxial Processing Cavities Based on the Theory of Electrostatic Fields

The coaxial processing cavity is an important component of high-frequency electromagnetic water treatment devices. Due to its easy installation, wide applicability, and excellent scale removal effect, it has been widely used in various factories. To study the influence of excitation source waveform, processing cavity length, and anode-cathode radius ratio on the intensity and distribution of the electromagnetic field in the coaxial processing cavity under time-varying fields, this paper derives the numerical calculation formula for electromagnetic energy in the coaxial processing cavity based on the theory of electrostatic fields. The finite element method is used to visualize the intensity and distribution of the electromagnetic field in the coaxial processing cavity. By optimizing the structure of the coaxial processing cavity, the optimal range of the anode-cathode radius ratio is determined. The research results show that, under the conditions of electrostatic field theory, square waves have the maximum electromagnetic energy, the length of the processing cavity does not affect the distribution of the electromagnetic field, and the optimal anode-cathode radius ratio range is 0.375-0.5.

Sea‐weeding: Manual removal of macroalgae facilitates rapid coral recovery

Abstract Coral reef ecosystems globally are under threat, leading to declining coral cover and macroalgal proliferation. Manually removing macroalgae (i.e. ‘sea‐weeding’) may promote local‐scale coral recovery by reducing a biological barrier, though the impact of removal on community composition of benthic reef organisms has not been quantified. In this three‐year study (2018–2021), fleshy macroalgae (predominantly Sargassum spp.) were periodically removed from 25 m2 experimental plots on two inshore fringing reefs of Yunbenun (Magnetic Island) in the central Great Barrier Reef. By the end of the study, coral cover in removal plots (n = 12 plots) assessed through in‐field transects increased by at least 47% (2019 mean: 25.5%, 2021 mean: 37.4%), and macroalgal cover decreased by more than half. In contrast, in control plots (n = 12 plots), there was no change in macroalgal cover while coral cover remained stable (2019 mean: 16.4%, 2021 mean: 13.6%). Changes in benthic cover were supported by photoquadrat data, with Bayesian probability modelling indicating a 100% likelihood that coral cover more than doubled in removal plots over the study period, compared to only a 29% chance of increased coral cover in control plots. Synthesis and applications. Manual macroalgal removal can provide rapid benefits and enhance inshore coral reef recovery. Through involvement of community groups and citizen scientists, larger scale removal of macroalgae is a low‐tech, high‐impact, and achievable method for local reef management.

Deep eutectic solvent-mediated one-step eggshell removal and anti-felting of wool

The sheep lice eggshells and felting are both important problem in wool industry. Deep eutectic solvents (DES) are a class of eco-friendly and low-cost solvents that are used in various fields including the anti-felting of wool but not in the eggshell removal. In this study, the simultaneous removal of wool scales and lice eggshells using [ChCl:Urea] was achieved by optimizing the formula and condition. Satisfactory eggshell removal (80.0%) and anti-felting rates (22.7%) had little effect on the mechanical strength of the wool (12.1%). The mechanism of the beneficial effects was studied using scanning electron microscopy and Fourier-transform infrared spectroscopy. The loose structure of protein cement is conducive to the penetration of DESs to achieve complete disintegration and dissolution. In contrast, the dense wool structure prevents DESs from penetrating the interior and only removes the surface scales. In addition, dissolution of eggshells by DES also helps in its removal. To our knowledge, this is the first report of DES-mediated one-step eggshell removal and anti-felting of wool. Through economic and environmental effects analyses, DES-based technique exhibits a more promising potential for industrial applications. This work not only has significant application prospects in the wool industry, but also the application scenarios of DESs.

METHODS OF ENERGY SAVING IN DEVICES FOR HYDRO-CRACKING OF SCALE

The cause of scale formation on the cast blanks and in the process of ivy is considered, the difference between the physical properties of the scale and base metal is shown, which reduces the quality and stability of the metal, and also complicates the processing of the product. The proposed effective way to remove the scale, which is environmentally friendly, does not require additional water treatment and does not deform the metal surface. The analysis of devices for removal of scale from the metal surface showed that the first collectors with nozzles had problems with operation: high water and energy consumption and poor cleaning of the metal surface. They are proposed to replace them with a hydraulic device with a rotary principle with rotary heads that use very low cost at high impact pressure, which also reduces electricity consumption. A comparative table of ordinary collectors and collectors with a different principle is provided by improving the design of devices for supplying fluid to the metal surface with the quality of cleaning of the metal from scale. Electricity is proposed. It is revealed that you can reduce the eager expenses by optimizing the operation of the pumping station. The optimization result is given in the form of an energy saving schedule in the period of hydraulic pauses by means of an adjustable electric drive with frequency control and hydraulic rods. It is proposed on the basis of the analysis of devices for removal of scale another way to reduce electro -energy by improving the design of water supply devices to the metal surface by improving their properties. It is revealed that not only the features of the design of the nozzles, but their optimal location, plays an important role in removing the scale. The hydraulic scale system is fully controlled by the machine, which allows to regulate the parameters of removal of the scale and to provide the required working pressure in the system, to compensate for the wear of the nozzles.

Generality of Evaporative Crystal Liftoff on Heated Hydrophobic Substrates

Scaling or mineral fouling occurs due to the presence of dissolved minerals in water. Scaling is problematic in numerous industrial and household plumbing applications where water is used. The current methods of scale removal often utilize harsh chemicals that are not environmentally friendly. The evaporation of a saline droplet provides a platform to study the role of the substrate in the dynamics of crystallization during scaling. In the present work, we show out-of-plane growth of crystal deposits during the evaporation of saline droplets of aqueous potassium chloride on a heated smooth and microtextured hydrophobic substrate. These out-of-plane deposits, termed as "crystal legs", are in minimal contact with the substrate and can be easily removed from the substrate. The out-of-plane evaporative crystallization of saline droplets of different initial volumes and concentrations is observed irrespective of the chemistry of the hydrophobic coating and the crystal habits investigated. We attribute this general behavior of crystal legs to the growth and stacking of smaller crystals (size ∼10 μm) between the primary crystals toward the end of evaporation. We show that the rate at which the crystal legs grow increases with an increase in the substrate temperature. A mass conservation model is applied to predict the leg growth rate, which agrees well with the experiments.