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Petroleum Geochemical Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Plant organisms synthesize an odd number of carbon atoms in the hydrocarbon chain, generally from C25 to C37. The most dominant carbon atoms are C27, C29 and C31. The marine plants synthesize smaller odd chain length hydrocarbons from C15 to C21 compared to the land plants. They contain high percentages of unsaturated hydrocarbons from one to six olefin bonds. The most dominant are C19 and C21 carbon atoms. Waxes are solid and characterized by their melting point that ranges from 35 to 110°C. Waxes are lubricating materials; they produce a sliding surface. They are like oil and fat, and do not dissolve in water, but are soluble in organic solvents. Waxes are synthesized and maintained mostly by land plants and animals. Waxes are chemically a mixture of long chain fatty acids, free fatty acid and long chain monohydric alcohols. Waxes contain generally even number carbon atoms in the range from C16 to C38.
Nutrient Recovery from Food, Industrial and Processing Waste and Effluent Disposal Points in River and Estuary
Published in Hossain Md Anawar, Vladimir Strezov, Abhilash, Sustainable and Economic Waste Management, 2019
Hossain Md Anawar, Md Zabed Hossain, Vladimir Strezov, I. Santa-Regina, Farjana Akter
The activated sludge process of sugarcane mills wastewater treatment produces press mud with significant fertilizer value due to the rich source of organic matter, organic carbon, sugar, protein, enzymes, micronutrients (N, P and K) and macronutrients (Zn, Fe, Cu, Mn, etc.), and microbes (Sangam et al., 2008). However, its bad odour and high transportation cost creates concerns among the farmers. There is a perception by the farmers that sludge application may lead to crust formation, pH variation and pollution problems. Its high rate of direct application (up to 100 tonnes/acre) may increase soil sickness and water pollution due to its wax content (8.15%). Conventional composting of press mud takes about 6 months and does not remove the foul odour completely and thus the produced compost has less nutritive value and more compactness. The vermicomposting can recover nutrients from press mud, increase nutritive value and remove odours. The urban, industrial and agro-industrial wastes can be vermicomposted using earthworms to produce biofertilizers and peatlike material that is much more fragmented, porous and microbially active than the parent material due to humification and increased decomposition.
Application of Nanotechnology in the Safe Delivery of Bioactive Compounds
Published in V Ravishankar Rai, Jamuna A. Bai, Nanotechnology Applications in the Food Industry, 2018
Behrouz Ghorani, Sara Naji-Tabasi, Aram Bostan, Bahareh Emadzadeh
Waxes are esters of fatty acids. In contrast to fats and oils, the fatty acids are not esters of glycerol but of higher primary monovalent alcohols. Waxes are practically insoluble in water. The color of beeswax varies from nearly white to brownish. It melts in the range of 62–64°C. Beeswax is compatible with most other waxes and oils, fatty acids, glycerides, and hydrocarbons. Carnauba wax is one of the hardest natural waxes. The melting point is in the range of 78–85°C (typically 83°C). The compatibility with other materials is similar as for beeswax. Candelilla wax is soluble in many organic solvents. It is light brown to light yellow and melts in the range of 67–79°C. It is not as hard as carnauba wax. It is compatible with all vegetable and animal waxes, fatty acids, a large variety of natural and synthetic resins, glycerides, and hydrocarbons in certain proportions, origin, and isolation of waxes. Waxes are isolated from animal and plant products. Beeswax is secreted by young honeybees to construct the honeycomb. Carnauba wax is obtained from the leaves of palm trees preferably in Brazil. Candellila wax is derived from the leaves of the Candelilla shrub, which grows in northern Mexico (Zuidam and Nedovic 2009).
An insight into wax/asphaltene deposition behavior in the wellbore regions of gas condensate reservoirs
Published in Petroleum Science and Technology, 2023
Zhihua Wang, Bowen Shi, Yang Song
Wax is a complex multi-component organic mixture in the condensate, mainly composed of hydrocarbon compounds and non-hydrocarbon compounds (Luo et al. 2022; Zhao et al. 2022; Wang et al. 2021). Under reservoir conditions, they tend to remain dispersed in the condensate. During gas condensate well production, changes in temperature, pressure, and composition can disturb the system stability and lead to wax precipitation (Wang et al. 2019). It not only contains high-carbon hydrocarbons in the condensate, but also contains asphaltene, sediment, other semi-solid or solid substances, and mechanical impurities (Guo et al. 2022; Liu et al. 2019). And asphaltene is a dark brown or black brittle solid. It is insoluble in petroleum ether, but soluble in strong polar organic solvents, such as chloroform and carbon disulfide. It is a polyaromatic molecule surrounded by aliphatic and heteroatomic chains (N, O, S), they can have also metals (Fe, Ni, V) (Speight 2004). As well, when a water phase is involved in the condensate the deposition behavior of asphaltene is aggravated by hydrogen bonding, making the deposition behavior more severe (Hashmi and Firoozabadi 2016; Aslan and Firoozabadi 2014). Once precipitated, these asphaltene particles will deposit on the inner surface of the wellbore, reducing the available flow area and increasing production pressure (Mohammed et al. 2021; Sulaimon, Castro, and Vatsa 2020; Ye, Long, and Dai 2022; Xu et al. 2021).
Wax actuator’s empirical model development and application to underfloor heating control with varying complexity of controller modelling detail
Published in Journal of Building Performance Simulation, 2023
Tuule Mall Parts, Andrea Ferrantelli, Hendrik Naar, Martin Thalfeldt, Jarek Kurnitski
Thermoelectric wax actuators are electrically controlled and use paraffin wax as phase change material (PCM) for volume change (Burt and de Podesta 2020; Danfoss A/S 2017). The wax is solid at room temperature and liquid at higher temperatures. It is heated by a positive temperature coefficient (PTC) heater. These actuators are known by other names as well, such as wax motors (used in this work, abbreviated as WM), wax pellet actuators, thermo-electric actuators, or thermal actuators (Ventilation Control Products Sweden AB 2022; Klimeš, Charvát, and Ostrý 2019; Li et al. 2020; Goia, Chaudhary, and Fantucci 2018). In the absence of an electric heating signal, the system actuator-valve is normally closed. When voltage is applied, the wax starts melting and expanding, thus moving the valve’s piston. By the action of a system of springs, the piston movement reduces the actuator’s inner height, thus opening the valve. Such method of valve control has been used in UFH for a long time, as the actuators are silent and durable (Wetter 2009). Slower reactions also avoid the water hammer that is associated with motorized valves. Additionally, wax actuators are used before fan coils in cooling systems, and for pressure-independent control valves in heating systems. Radiator thermostats also include similar motors; however, these are often based on the expansion of liquid or gas instead of the phase change of the wax.
Advances in the research of polymeric pour point depressant for waxy crude oil
Published in Journal of Dispersion Science and Technology, 2018
Na Li, GuoLiang Mao, XianZhi Shi, ShiWei Tian, Yang Liu
The wax in crude oil is a mixture of hydrocarbons above C16, of which C16∼C36 is called paraffin wax. Paraffin wax is mainly composed of n-alkanes, alkanes, naphthenic, and alkyl aromatic hydrocarbons.[63] C30 ∼ C60 is usually referred to as wax or microcrystalline wax, which mainly consists of naphthenic hydrocarbons and aromatic hydrocarbons, while n-alkanes and alkanes are relatively few. Wax precipitates continuously from oil phase when the temperature of crude oil is below WAT.[68]