Experimental and numerical investigations on the heat production and thermal storage characteristics of rapid preparation amorphous powder activated coke

The heat production and thermal storage characteristics of rapid-preparation amorphous powder activated coke (RAC) were investigated. RAC was prepared by using a drop-tube reactor system. The natural oxidation characteristics of RAC were studied through combined TG–FTIR analysis and temperature-programmed experiment. Experimental results showed that CO and CO₂ were the main oxidation products of RAC in air, and that the oxidation reaction was in accordance with the Arrhenius equation and law of mass action. Thermal storage characteristics were studied through computational fluid dynamics simulation. The maximum excess temperature θ_max increases linearly with the increase of the initial temperature. The concentration fields of the products show that CO₂ is mainly concentrated in the upper part of the coke bin, and the CO generated by CO₂ at high temperature is mainly concentrated in the central part of the coke bin.     

生产工艺多方案并行与快速转换方法研究

生产系统复杂多变,在生产管理过程中存在多变性和不均衡性。对此,实际生产中需要实现生产工艺多方案并行与快速转换。分析了生产过程变化因素,介绍了主工艺+子工艺这一生产工艺多方案并行与快速转换方法,并通过实例验证了这一方法的有效性。     

某油田油井采出水腐蚀因素研究

我国油田油井生产中采油井管柱腐蚀现象十分普遍,所以在注CO_2驱进行开采过程中要进行采出水的质量分析。对现阶段的油田生产腐蚀及防腐技术进行论述,提出相对应的防腐措施,进一步为油田生产作业提高产量。     

Effects of CuO nano powder on performance improvement and entropy production of double-pipe heat exchanger with innovative perforated turbulators

The objective of the present numerical study is to investigate the heat transfer enhancement, entropy generation, and thermal performance of turbulent nanofluids inside double-pipe heat exchangers equipped with novel perforated cylindrical turbulators. Effects of inflow velocity, CuO nanoparticles volume fraction and perforated index are evaluated on the Nusselt number, friction loss, thermal performance factor (η), and viscous irreversibilities of the double-pipe heat exchangers. The newly proposed perforated turbulators with CuO nanopowder with ϕ = 1.5% provide the thermal performance of η = 1.931, which is considerably higher than the other previous studies. The results show that raising PI reduces the turbulent kinetic energy, especially in outer regions of the cylindrical turbulator. The jet formation near the walls and the perforations is the primary physical reason for this. The viscous entropy generation is increased up to 153.0% by increasing the Re number from 6,000 to 17,000 for PI = 8% and DR = 0.7. Thermal boundary layer disruption is the primary physical reason for heat transfer enhancement.     

Hydrogen and ethanol: Production,storage, and transportation

The present paper provides insights into the feasibility of using hydrogen and bioethanol blends as energy carriers in the foreseeable future upon discussions on the advantages and the disadvantages. The comprehensive overviews on the production, storage, and transportation of hydrogen and bioethanol have been made; and the current problems and potential solutions for the three stages have been summarized. Finally, the prospections on hydrogen and bioethanol could be expect optimistically.     

Status of Mysis diluviana in Lake Ontario in 2013: Lower abundance but higher fecundity than in the 1990s

Mysis diluviana is a major component of prey fish diets in the Great Lakes, so annual production of M. diluviana is important for understanding and modeling energy flow through Great Lakes food webs. However, only three lake-wide measurements of M. diluviana annual production in Lake Ontario are currently available (1971, 1990, 1995). During 2013, lake-wide coverage of Lake Ontario was achieved during four periods from April to November. Annual mean density and biomass of M. diluviana in 2013 were 99?#/m² (SE: 8) and 318?mg?dw/m² (SE: 28) – approximately half of values observed in 1990s. M. diluviana comprised 13–30% of offshore zooplankton biomass in each period. Reproduction peaked in fall, with mean brood size of 32 embryos (range: 11–49), at least 10% larger than in 1990s. Generation time was two years from embryo to initial reproduction. Growth rates were 0.052?mm/d for the age-0 cohort and 0.027?mm/d for the age-1 cohort. Age-0 growth rate was significantly higher than in 1980s–90s (0.035?mm/d). Annual production in 2013 was 0.85?g?dw/m²/yr (SE: 0.03) which was 30–40% of values observed in 1990 and 1995 (2.23 and 2.53?g/m²/yr). Annual production to biomass ratio (P/B) in 2013 was 2.65?/yr which was 80–85% of values observed in 1990 and 1995 (3.24 and 3.11?/yr), but this difference was not statistically significant. Our results suggest that changes in annual production over time can be estimated using changes in biomass over time and a mean P/B ratio.     

简析变压器油的生产工艺及质量

本文简要介绍了变压器油的运用价值,同时分析如何实现对变压器油生产工艺的优化,并从物理性能以及化学性能两个方面分析生产工艺改良后变压器油整体质量,以期为变压器油生产工作提供一定的参考与帮助。     

2019年重庆市食品生产许可现场核查分析及建议

目的 分析2019年重庆市食品生产许可现场核查中出现的问题。方法 依据《食品、食品添加剂生产许可现场核查评分记录表》六个部分条款梳理现场核查缺陷,对209个不予许可食品类别进行汇总分析。结果 六个部分条款出现零分项频率递减为生产场所、设备设施、管理制度、人员管理、设备布局和工艺流程、试制产品检验报告,生产场所缺陷频率略少于设备设施,不予许可食品类别依次递减为调味品、蔬菜制品、豆制品、速冻食品、其他食品。结论 通过梳理许可现场核查中的个性或共性问题并提出对策,以期能为相关工作技术人员提供指导和借鉴。     

白象山铁矿精细化成本管控体系的构建及应用

铁矿是一种重要的矿物资源，其价格主要由市场决定。因此，在价格一定的条件下，铁矿企业要想进一步提高经济效益，提高市场竞争力，主要通过降低成本的途径来实现。以白象山铁矿为例，为实现白象山铁矿原矿成本控制，主要从技术创新和生产管理出发，通过采用防治水技术优化、采用安全高效采矿工艺、分级支护、大数据精准充填、自动化技术攻关、生产管理降本、财务收支管理降本、技术管理降本、增加零星工程自营等多种方法来降低成本。精细化成本管控体系不仅为该矿创造了巨大的经济效益，而且可为其他类似条件的矿山提供借鉴。     

铜山口铜矿坑内钻勘探的生产实践

随着铜山口铜矿地下深部基建结束，坑道探矿存在安全事故隐患、地质取样质量无法保证的问题，为了加快生产探矿，发挥坑内钻优势，弥补坑道探矿不足，购置了3台坑内钻进行探矿。通过在主矿体生产探矿及周边扫盲增储、尖灭矿体探边摸底、零星小矿体追寻、超前探水、指导巷道掘进方向等应用，结果表明，坑内钻具有操作灵活机动，易掌握，缩短了生产探矿时间，节约探矿成本，作业现场安全等优势，保持了三级矿量的动态平衡，确保了生产持续稳产发展。