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1.
A small stainless steel reactor about one-millionth the volume of a home kitchen, was built to generate odors from cooking oils heated to deep fat frying temperatures. This “microroom” was designed so that volatiles could be collected from 1–5 ml of heated oils (193 C) directly on a gas chromatographic column, cooled to -60 C and subsequently separated by temperature programing up to 250 C. Evaluations showed that heated oil odors from the microroom were similar to those room odors produced by heating to 193 C 300 ml of cooking oil in an open vessel; exposure to subambient conditions did not affect the separation efficiency of the gas chromatographic column. Provisions were made for three independent means of effluent monitoring: flame ionization detection, odor analyses and mass spectrometry. Presented at the AOCS Meeting, Los Angeles, April 1972. ARS, USDA.  相似文献   

2.
In edible oil refining, the various processes in current use lead to different by-products and/or waste products and they may also cause some form of pollution. The processes are reviewed in this paper and current or possible means of disposal of these by-products/waste products are discussed to highlight the areas requiring most attention. These areas turn out to be gum disposal when the degumming operation is carried out at a stand-alone refinery, and soapstock effluent resulting from the alkali refining process. Other waste products and pollution sources are found to be unimportant or manageable. Accordingly, a major step forward in pollution abatement in seed oil refining can be achieved by making two changes. The first one entails carrying out the degumming operation at the oil mill rather than at the refinery. This should be done in such a way that the degummed oil is amenable to physical refining. The acid refining process is recommended for this degumming step and consequently, acid refined oil with appropriate quality guarantees will then become the article of trade. The second one involves a switch from alkali refining crude or waterdegummed oil to the physical refining of acid refined oil. For this latter step, a counter-current process is recommended because of its low stripping steam requirement. Dry condensation of the distillate will further alleviate pollution problems associated with deodorization and physical refining. Finally, some processes, that may contribute to pollution control but that still require development, are mentioned.  相似文献   

3.
The utilization of industrial off-gases as raw material requires a detailed knowledge on their time-depending composition, especially with regard to trace components. Within the framework of the HüGaProp project (Hüttengas Properties) a measuring container and the analytical methods for the characterization of trace components in the three raw metallurgical gases was developed. The mobile container is deployed in the project Carbon2Chem® to characterize the available off-gases at a steel mill and provide fundamental data to determine the required gas cleaning as well as the background for the further process design.  相似文献   

4.
Occupational cotton dust control technology was evaluated in 10 oil mills throughout the cotton belt of the U.S. This evaluation was restricted to mechanical portions of each mill: seed cleaning, delintering, hulling and separating, and linter baling. Based on the process machinery observed in these mills, a 500 ton/day model cottonseed oil mill was designed. The occupational dust control systems for this mill were based on current state-of-the-art technology observed during this project. Further improvements based on readily available air pollution control devices have been incorporated. In order to achieve minimal respirable dust concentrations in the mill, all dust emission points have been enclosed to the maximal extent consistent with efficient plant operations. The various processing areas in the mill were designed with negative pressure dust control systems separate from the general ventilation system. The dust control system includes coarse dust removal by high-efficiency cyclones whose effluent discharges into pulse-jet fabric filter bag-houses operated at an air-to-cloth ratio of 20:1. The emission control system for saw-type delinter systems were divided into small units to reduce the deleterious effects of fires. In order to conserve space, Figures 4, 5, 9, 10, 11, 12, 13, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 28, 29 and 30 are not shown, even though they are referenced in the text. Readers desiring copies of these may obtain them at reproduction costs from the authors.  相似文献   

5.
Increasingly stricter specifications for plant effluents, may now require tertiary treatment to meet water soluble chemical oxygen demand and biochemical oxygen demand limits. This paper describes a system in which the effluent water from a tall oil plant is treated and recycled to the process instead of being treated and discharged. One of seven papers presented at the Symposium “Tall Oil,” AOCS Meeting, New Orleans, May 1973.  相似文献   

6.
立磨磨辊轴向密封圈采用油和气体两种密封设计,其结构设计周密,能严格控制油和气体的工作压力.还应重视装配质量,以提高密封效果,避免粉尘进入,可有效提升磨辊轴承的使用寿命.  相似文献   

7.
Residual oil recovery from the centrifuge sludge of a palm oil mill was investigated by treating with enzyme (Celluclast) followed by washing the digested substrate with surfactant. The optimal conditions for enzyme digestion with respect to pH, temperature, reaction time, concentrations of enzyme and surfactant were evaluated. The possible role of the surfactant in the oil recovery process is discussed. The chemical composition and physical properties of the sludge before and after treatment were determined and its significance in the subsequent effluent treatment/utilization of the sludge is discussed. Part of this work was presented at the American Chemical Society’s 63rd Colloid and Surface Science Symposium, Seattle, Washington, June 18–20, 1989.  相似文献   

8.
The treatment of effluent from a paper/board factory that produced 280 tons of cardboard and consumed 1200 m3 of water per day was carried out. Wastewater analysis showed that the mill effluent contained 3000 mg dm?3 suspended solids, 1400 mg dm?3 COD (chemical oxygen demand) and 500 mg dm?3 BOD (biochemical oxygen demand). An internal treatment cycle is suggested that involves recirculation of paper‐machine wastewater (white‐water) and may be accomplished by installing a flotation saveall (fiber recovery) unit. This arrangement reduced fresh water use by about 90%, reduced fiber loss by 80–90%, and increased board production by 13%. An external treatment process for the effluent was assessed by conducting laboratory coagulation tests (alum, ferric chloride, ferrous sulfate, and polyelectrolyte) on the whole mill effluent. Oxidation of the mill effluent using calcium hypochlorite before discharging the effluent to a lagoon offers the benefits of killing the harmful bacteria and reducing the pollution load. Copyright © 2003 Society of Chemical Industry  相似文献   

9.
Traditionally, hydrocarbons have been used for biosurfactant production. However, urban waste, peat pressate and agroindustrial by-products, such as olive oil mill effluent and acid whey, are possible substitutes for microbial growth and biosurfactant production. The state of the art has been reviewed, augmented by some new information onPseudomonas fermentation of olive oil mill effluent. More research is needed to improve yields and production economics.  相似文献   

10.
油田生产中的细菌危害与杀菌技术   总被引:6,自引:0,他引:6  
在油田生产过程中,常常要使用多种有机化学药剂,加上其他环境条件(如温度、pH值、无机盐、溶解氧等)的适宜,往往会造成钻井液、完井液、压裂液、污水、注水的细菌污染,为了保证油田生产的正常进行,必须采取有效的措施控制细菌的危害。本文介绍和讨论了油田生产中的细菌危害及其杀菌技术,指出新型杀菌剂应向一剂多效方向发展。  相似文献   

11.
张华  刘光全  张晓飞  罗臻 《化工进展》2022,41(9):5047-5054
石油炼制行业电脱盐废水乳化严重、破乳难,影响后续深度处理,已成为企业污染防治的重要难题。本研究针对典型炼化企业电脱盐废水的排放与处理需求,实时跟踪电脱盐废水的水质波动。基于电脱盐废水的污染组成特点,分析其稳定性,并首次利用管式电絮凝处理电脱盐废水。结果表明,该企业电脱盐反冲洗时,电脱盐废水中石油类浓度>400mg/L,最高时可达1700mg/L,显著高于设计值。其化学需氧量(COD)平均为4484mg/L,与原油性质密切相关,其中溶解性COD约765mg/L,主要来源于电脱盐注水。反冲洗废水中胶质、沥青质重质组分占总油比例28%,高于正常排水。电脱盐废水具有一定的自发破乳性,但时间较长;曝气预处理30min后COD可降至原水的26.2%;电絮凝可进一步大幅降低COD与溶解性COD,且在初始电流1.0A、反应时间15min时,COD和溶解性COD的平均去除率分别达到80%和50%,降解过程符合准一级动力学模型,此时直接运行成本约0.92CNY/m3废水。  相似文献   

12.
Summary A study has been made of the detergency and foaming power of soaps made from a typical acid-refined American tall oil. Sodium soap of tall oil, straight tall oil fatty-acid soap, and straight tall oil resin-acid soap were evaluated. The effect of fatty acid-resin acid ratio was determined by using mixtures of those soaps. Sodium rosinate, sodium oleate, and mixtures of these soaps were used as comparison standards. Curves plotted show wash-test data and foaming values as functions of the ratio of fatty soap to resin soap. The data indicate in terms of detergency: a) tall oil soap has a higher value than sodium rosinate; b) sodium oleate is better than tall oil fatty-acid soap, but the latter is approximately equivalent to soaps from various unsaturated vegetable oils; c) both tall oil resin-acid soap and rosin soap have low detergency on cotton; d) the detergency of most mixtures of tall oil fatty-acid and resin-acid soaps at lower concentrations is greater than would be predicted from the individual soaps, indicating a synergistic effect. As a rough approximation, tall oil soap without unsaponifiables is equivalent to a corresponding mixture of sodium oleate and sodium rosinate. The presence of unsaponifiables lowers both detergency and foaming. Tall oil soap is somewhat less sensitive to hard water than sodium oleate. Significant differences between detergencies of soaps, and especially between soap mixtures, are obscured when launderometer tests are run at moderate soap concentrations. These differences are readily detected at lower concentrations. Presented at 113th meeting of the American Chemical Society, Chicago, Ill., April 14–23, 1948.  相似文献   

13.
The handling and control of the raw materials for the oil seed industry can be primarily characterized by the short harvest season, by the necessity to move them into protected storage in minimum time, and by the required care before they can be processed. But they can be treated and stored successfully with minimal deterioration long enough to allow the processing industry to operate throughout the year. Soybeans, cottonseed, flax, safflower, and other oil seeds are subject to damage primarily from biological actions, which are accelerated by high moisture content, foreign material, physical damage, and such adverse climatic conditions as frost or rain before harvest. The primary object of the storage units, cleaners, and dryers used by oil mill processors is to minimize further damage and to reduce the effects of damage occurring prior to receipt. The various types of machinery, equipment, and storage units to accomplish this objective successfully are discussed. It is possible to design and build equipment and storage units which will theoretically handle almost any situation, but the capital investment would be so large that carrying charges would prevent a profit in the market place. Accordingly the oil seed processor must combine ingenuity and foresight with hard work to provide a solution to the problems of each season in an industry where no season is entirely like any other. Presented at the AOCS Short Course, East Lansing, Aug. 29–Sept. 1, 1966.  相似文献   

14.
About 1949, with the advent of effective fractional distillation, the tall oil industry came of age, and tall oil fatty acids (TOFA), generally any product containing 90% or more fatty acids and 10% or less of rosin, have grown in annual volume ever since, until they amount to 398.8 million pounds annual production in the U.S. in 1978. Crude tall oil is a byproduct of the Kraft process for producing wood pulp from pine wood. Crude tall oil is about 50% fatty acids and 40% rosin acids, the remainder unsaps and residues; actually, a national average recovery of about 1–2% of tall oil is obtained from wood. On a pulp basis, each ton of pulp affords 140–220 pounds black liquor soaps, which yields 70–110 pounds crude tall oil, yielding 30–50 pounds of TOFA. Separative and upgrading technology involves: (a) recovery of the tall oil; (b) acid refining; (c) fractionation of tall oil; and occasionally (d) conversion to derivatives. TOFA of good quality and color of Gardner 2 corresponds to above 97% fatty acids with the composition of 1.6% palmitic & stearic acid, 49.3% oleic acid, 45.1% linoleic acid, 1.1% miscellaneous acids, 1.2% rosin acids, and 1.7% unsaponifiables.  相似文献   

15.
针对焦化废水中油分粒径小、去除难的特点,采用自行设计的组合除油系统处理废水中的油分。结果表明:废水中的油主要是分散油和乎k化油,粒径分布集中在5-60μm;除油系统在设计负荷下运行稳定,出水中油分浓度约为90mg·L^-1,平均去除率约为70%,残留油分可通过生物降解进一步处理:出水中的油主要是溶解油和乳化油,90%的油珠粒径小于25μm;预处理后,废水的TTC从15.92μg·h^-1。提高到18.12μg·h^-1,BOD5/CODCr比值从0.30提高到0.35,为后续的生物处理奠定了基础。  相似文献   

16.
A commercial-scale Fluidized Bed Incinerator (FBI), which has a capacity of 60 tons per day to treat dewatered sludge and waste oil or solvent, was developed as one of the governmental R&D projects from 1990 to 1997. From the design, construction and operation of the plant, the characteristics of co-combustion and appropriate operating conditions with successful fly ash recirculation and with effluent controls have been investigated. Without adding any bed materials, sand, the co-incineration of sludge and spent-solvent can be achieved. The sludge combustion steps could be observed and confirmed, which consist of evaporation, agglomeration, devolatilization, combustion and attrition. The plant can also incinerate various types of sludge from wastewater treatment facilities with waste oil or solvent. ‡Presented at the Int’l Symp. on Chem. Eng. (Cheju, Feb. 8–10, 2001), dedicated to Prof. H. S. Chun on the occasion of his retirement from Korea University.  相似文献   

17.
介绍了冶炼烟气制酸废热锅炉的结构及设计要点。根据冶炼烟气尘含量高且烟尘粘结性强、烟气腐蚀性强及烟气波动性大的特性,废热锅炉设计时有针对性地对锅炉进行热工计算及结构选型,采用垂直烟道纵横向冲刷型锅炉并合理选择运行参数、加强振打除灰,以确保锅炉在恶劣工况下的适应性和安全性。  相似文献   

18.
Panel evaluations have been made of room odors developed by edible oils and cooking fats heated to frying temperatures. Vegetable and mixed fat shortenings, as well as oils of different iodine value and from special processing, were investigated with and without added stabilizers. When silicones were added to frying fats, room odor scores improved markedly. Certain added autoxidative cleavage products had little effect on odor scores at levels where they were detected easily in taste tests. To be discernible in room odors, these additives had to be present at levels ca. 100-fold greater than their taste thresholds. Panel results show that the undesirable frying odors contributed by unhydrogenated soybean oil in mixtures with other oils could be detected readily at 25% levels. As the level of soybean oil was lowered further, the room odor scores of oil mixtures improved perceptibly. One of 13 papers presented in the symposium “Flavor Research in Fats and Fat Bearing Foods,” AOCS Meeting, Atlantic City, October 1971. N. Market. Nutr. Res. Div., ARS, USDA.  相似文献   

19.
针对大型棒磨机达不到设计产能、漏浆严重、出现乱棒、条筛断裂等问题,结合棒磨机的结构特点及技术特性等,探讨改进措施,实现了棒磨机的稳定、可靠运行。  相似文献   

20.
This pilot-scale study deals with highly polluting agro-industry's wastewater, palm oil mill effluent (POME). Ceramic ultrafiltration membrane was applied to treat this effluent. UF separation behavior of POME is reported. The effects of transmembrane pressure and crossflow velocity on permeate flux, limiting flux and percentage rejection for suspended solids and dissolved organic matters were investigated. The limiting flux obtained was further applied to determine critical flux and deposit resistance, Rc, using the possible theoretical link of critical flux and limiting flux. The verified values of critical flux are useful in the operation of ultrafiltration to minimized membrane fouling; thus, longer lifespan of the membrane can be expected. Both transmembrane pressure and crossflow velocity show their significant effects to the permeate flux, whereas only the crossflow velocity influences the rejection of dissolved organic matters in terms of COD and BOD.  相似文献   

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