Industrial Applications
Vlado Valković in Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
The use of coal for power production has a serious side effect that of atmosphere pollution by exhaust flue gases. Consequently, lots of effort has gone into finding the processes, which can improve this situation. One of the radiation processes which was successfully demonstrated in many laboratories and pilot plant facilities is the reduction of SO2 and NOx pollutants from flue gases emitted during fuel combustion in boilers for electrical power and heat production (Zimek 1995). The full-scale industrial implementation of an EB process for flue gases treatment would require accelerator modules with a beam power of over 500 kW and electron energy in the range 1–1.5 MeV. The 500 MW power plant may require 5–8 MW of EB power deposited in the flue gas.
Techno-Economic Analysis of Multiple Scenarios for the Production of Microalgal Chemicals and Polymers
Gokare A. Ravishankar, Ranga Rao Ambati in Handbook of Algal Technologies and Phytochemicals, 2019
Regarding the OPEX, the total costs of the raw materials and utilities were identified by the simulation of the total plant and the individual operation of the major process steps. The total value for these categories is €40,601,637/year (63.68% for raw materials and 36.32% for utilities). The contributions of CO2 and nutrients (47.78% and 37.65%, respectively) are the largest among the remaining materials. Thus, it is safe to conclude that the feasibility potential of the plant will improve, provided that alternative low-cost sources for carbon, nitrogen and other nutrients will be used. For example, the CO2 contained in industrial flue-gases and the nutrients (nitrogen and phosphorous) from fertilizers could be exploited. Notice also that the contribution of process water is minimal, due to the already designed recycle streams.
Saving the human race: environmental sustainability
Théodore H MacDonald, Noël A Kinsella, John A Gibson in The Global Human Right to Health, 2018
We have already observed that it is practically impossible to ‘repack’ carbon once it has been released into the environment. Methods of capturing it and storing it underground – usually in space once required by oil or gas – have been elaborated, but at present they are prohibitively expensive. Another approach could be to develop technologies by which coal can be burned with greater efficiency (with more of the carbon being used to create heat, and less released). Encouraging progress in this regard has already been made over the past two or three decades, and includes the following. Washing the coal to reduce the sulphur content. This means that when it is burned, it releases far less sulphur dioxide (SO2) and ash. The production of sulphur dioxide produces a terrible environmental deficit. When it combines with water vapour, it forms acid rain.Precipitation, like the famous Cottrell precipitation, electronically captures up to 99% of the ash that rises up the flumes in factories.Flue gas desulphurisation can reduce sulphur dioxide release by up to 97%. This process is already routinely used in developed countries, but due to the expense involved is still largely absent in such large coal-producing countries as China.
Evaluating the efficiency of enzyme accelerated CO2 capture: chemical kinetics modelling for interpreting measurement results
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Lorenzo Parri, Ada Fort, Anna Lo Grasso, Marco Mugnaini, Valerio Vignoli, Clemente Capasso, Sonia Del Prete, Maria Novella Romanelli, Claudiu T. Supuran
Recently, it has been realised a three-phase bioreactor (gas, liquid, and solid), which was filled with the recombinant SspCA immobilised on polyurethane (PU)14. The results obtained using the lab-scale bioreactor showed that the immobilised PU-SspCA is capable of converting CO2 from a gas mixture, whose initial concentration was 20%. Russo et al., using the SspCA covalently immobilised on paramagnetic Fe3O4 nanoparticles via carbodiimide activation of the enzyme and the protocol based on CO2 absorption experiment in a stirred cell apparatus, determined the kinetics of the immobilised SspCA for the CO2 hydration reaction15. Abdelrahim et al.16 provided an innovative concept for the removal of CO2 from flue gas streams, using biomimetic SILMs (Supported Ionic Liquid Membranes) containing SspCA that enhances the selective transport of CO2.
Asbestos dust concentrations and health conditions of workers at asbestos-cement corrugated sheet production manufacturers in Vietnam: a nationwide assessment
Published in International Journal of Occupational Safety and Ergonomics, 2023
Hang Thi Le, Hoa Thi Dinh, Tam Thi Ngo
Asbestos fiber dust concentration analysis, presented in Table 1, showed that 108 out of 206 samples had asbestos fiber dust, accounting for 52.4%. However, none of the samples exceeded the national standards for the occupational exposure limits (OELs) (0.1 fibers/ml per 8 h and 0.5 fibers/ml per 1 h) [11]. The average concentration of asbestos fibers was 0.19 ± 0.14 fibers/ml, of which the highest in group 1 was 0.19 ± 0.15 fibers/ml, in group 2 was 0.19 ± 0.12 fibers/ml and in group 3 was 0.17 ± 0.11 fibers/ml. Our evaluation results were better than previous evaluations in 2009 (3/56 samples), 2010 (1/71 samples) and 2011 (1/54 samples) of 14 companies using asbestos in production [9]. This phenomenon could be explained because, recently, many asbestos-cement roof sheet manufacturers had actively invested in technology to treat the working environment, and install and renovate crusher dust extraction and mixer machines. Besides, the process of solid waste and boiler flue gas treatment had been effective when companies had installed a system of crushing and mixing asbestos in a closed cycle with cyclones to collect and treat dust. This investment had positive results when reducing the dust concentration from 3 to 4 fibers/ml to the current result, which was within the allowed standard limits of the Government of Vietnam. On the other hand, the government’s regulations on monitoring and managing air quality, especially in asbestos-using factories, as well as putting environmental quality standards into the factory quality assessment process helped improve the perception of factory leaders, thereby helping to improve the working environment for workers [10,12,13].
Levels of PCDDs/PCDFs in waste incineration ash of some Jordanian hospitals using GC/MS
Published in Toxin Reviews, 2021
Sharif Arar, Mahmoud A. Alawi, Nisreen E. Al-Mikhi
As Tables 2 and 3 show, the PCDD/Fs in hospital waste ash are almost broken down, and PCDD/Fs cannot be synthesized in a high-temperature environment like a furnace; thus, the PCDD/Fs content in bottom ash is extremely low compared to the limit value of 10,000 pg I-TEQ/g. Still if taking as example the lowest value of 206,000 pg I-TEQ/kg (sample 9 from Queen Rania hospital) × 40.9 bottom ash generation rates in kg/batch equals to 8.4 µg per batch. Assuming batches were produced daily; 8.4 µg per batch × 365 day equals to 3.1 mg per year. Table 5 shows the same calculations for all samples. These estimated amounts, produced per year, would pose future concentration accumulation of PCDD/Fs in landfills- and dumping sites. The IPEN Dioxin PCBs and Waste Working Group (2005) report that indicated contamination of chicken eggs near the dump site for bottom ash from incinerator on the edge of Peshawar, Pakistan with dioxins reaches 2.91 pg WHO-TEQ/g fat compared to eggs samples from Egypt containing 125.78 pg WHO-TEQ/g fat. Eggs near the medical waste incinerator in Accra, Ghana (50–661 pg WHO-TEQ/g fat) and eggs sampled near the facility in Yaoundé (4.6–11.40 pg WHO-TEQ/g fat) exceeded the limit by EU Regulation (Petrlik et al.2019). According to the EU Regulation (EC) N°1259/2011 maximum level (ML) for food with PCDD/Fs and dl-PCBs concentrations = 2.5 pg WHO-TEQ/g fat, above this level is considered to be contaminated and is not suggested for consumption. Avoiding dioxin (PCDD/Fs) formation in medical waste management could be achieved by using different technologies like using possible alternatives for incinerators like autoclaves and rotors, where a boiler generates steam for disinfection at ≥121 °C for 30 min (Diaz et al.2005). Appropriate treatment of bottom ashes and residues from flue gas cleaning is essential for the reduction of PCDD/PCDF releases into the environment (Stockholm Convention on POPs 2008).
Related Knowledge Centers
- Carbon Dioxide
- Carbon Monoxide
- Combustion
- Exhaust Gas
- Oxygen
- Soot
- Sulfur Dioxide
- Nitrogen
- Particulates
- Flue-Gas Desulfurization