Showing papers on "Co-processing published in 2021"

Advancing the application of bio-oils by co-processing with petroleum intermediates: A review

Abstract: Crude bio-oils, as sustainable and renewable energy sources generated from thermochemical conversion of forest, agriculture, waste and algae biomass feedstocks, have attracted particular attention to partially and even completely replace the fossil fuels over the past decades. However, due to their undesirable qualities such as high oxygen content, thermal instability, and high corrosivity, further upgrading is required for the direct application of bio-oils for petrol engines or thermal power plants. Various upgrading pathways, including emulsification, hydrotreating, supercritical fluid treatment, and co-processing are being investigated by different international research groups to produce marketable drop-in renewable transportation biofuels. Among them, co-processing bio-oils with petroleum streams in existing refineries is recognized as a more promising solution compared to other conventional upgrading methods because of less capital investment and higher fuel productivity. This work reviewed the up-to-date research activities in bio-oil co-processing including process scale-up, focusing more on the most recent work about pyrolysis oils co-processing in the fluid catalytic cracking (FCC) unit and its industrial implementation. The significant knowledge gaps in the co-processing are also outlined for future investigations.

A review on the co-processing of biomass with other fuels sources

Abstract: Co-processing of different biomass with coal, plastics, vacuum residue, and vacuum gas oil can be very good sources of generation of transportation fuels with value-added chemicals, high heating va...

The migration and transformation of chromium during co-processing of cement raw meal mixed with chrome-polluted soil

Abstract: To efficiently dispose of chrome-polluted soil, the co-processing of raw meal mixed with chrome-polluted soil in a tube furnace (laboratory experiments) and a cement rotary kiln (field-scale experiments) were tested. The migration and transformation reactions of chromium were analyzed and the environmental risk was evaluated. The average mass balance value was 91% for the laboratory experiments. In field-scale experiments, the mass balance values were 110% for the control experiments and 84% when 1% soil was treated. Therefore, only a small amount of Cr was volatilized into the flue gas. The average total Cr concentration in the soil samples was 403.25 mg/kg, and the ratio of Cr(VI) to total Cr was 1.83% or less. On average, 45.15% of Cr(III) was oxidized to Cr(VI) in laboratory experiments, while 87.94% of Cr(III) was oxidized in field-scale experiments, and the difference could be a result of the different calcination conditions. The materials in the cement rotary kiln make full contact with oxygen, and in this high temperature and oxidizing atmosphere, abundant CaO and MgO promote the oxidation of Cr(III) to CaCrO4. SiO2, Al2O3, and Fe2O3 reduce CaCrO4, which inhibits Cr(III) oxidation. The Cr concentration in the cement products was well below the Chinese standard limits. The physical properties of clinker conformed to the Chinese standards. Therefore, the treatment of 1 wt% chrome-polluted soil with a cement rotary kiln is technically feasible and experimentally safe.

Production of Sustainable Concrete by Using Challenging Environmentally Friendly Materials Instead of Cement

Abstract: The environmental problems accompanying concrete come from cement. This means that the final product i.e., concrete is an environmentally sociable material by itself. This guides us to play on the concrete constituents which cause the largest environmental impact, which is cement. Therefore, if we can abate cement amount and increase cementing materials which can substitute cement for concrete, we will be able to minimize the concrete impact on the environment. The saving of cement quantity in concrete can be realized by substituting it with diverse extra cementitious materials which are a by-product of another industry and waste of agriculture.

Hydrothermal Co-Processing of Coal Fly Ash Cenospheres and Soluble Sr(II) as Environmentally Sustainable Approach to Sr-90 Immobilization in a Mineral-like Form.

Abstract: Co-processing of radioactive effluents with coal fly ash-derived materials is recognized as a resource-saving approach for efficient stabilization/solidification of radioactive components of wastewater. In this context, the paper is focused on the hydrothermal synthesis of Sr2+-bearing aluminosilicate/silicate phases as analogs of a mineral-like 90Sr waste form using hollow glass-crystalline aluminosilicate microspheres from coal fly ash (cenospheres) as a glassy source of Si and Al (SiO2-Al2O3)glass) and Sr(NO3)2 solutions as 90Sr simulant wastewater. The direct conversion of cenosphere glass in the Sr(NO3)2-NaOH-H2O-(SiO2-Al2O3)glass system as well as Sr2+ sorption on cenosphere-derived analcime (ANA) in the Sr(NO3)2-H2O-ANA system were studied at 150–200 °C and autogenous pressure. The solid and liquid reaction products were characterized by SEM-EDS, PXRD, AAS and STA. In the Sr(NO3)2-NaOH-H2O-(SiO2-Al2O3)glass system, the hydrothermal processing at 150–200 °C removes 99.99% of the added Sr2+ from the solution by forming Sr-tobermorite and Sr-plagioclase phases. In the Sr(NO3)2-H2O-ANA system, Sr2+ sorption on analcime results in the formation of solid solutions (Na1−nSrn/2)AlSi2O6·H2O of the Na-analcime–Sr-wairakite series. The results can be considered as a basis for the development of environmentally sustainable technology for 90Sr removal from wastewater and immobilization in a mineral-like form by co-processing waste from coal-fired and nuclear power plants.

Modeling the air pollutant concentration near a cement plant co-processing wastes

Abstract: In this study, we conducted full life-cycle studies on pollutants in a cement plant co-processing hazardous waste (HW) via the combined use of thermodynamic equilibrium calculations and the American Meteorological Society/Environmental Protection Regulatory Model.

Co-processing of waste plastic in cokers

Abstract: Systems and methods are provided for co-processing of plastic waste in a coking environment or other thermal conversion environment. The co-processing of plastic waste in a coking environment can be performed by performing four types of processes on the plastic waste. The plastic waste can be conditioned by classifying and sizing of the plastic waste to improve the suitability of the plastic waste for co-processing. The conditioned plastic waste particles can be entrained and/or dissolved into a solvent and/or the base feed. The solution and/or slurry of plastic waste can be passed into a coking environment, such as a fluidized coking environment or a delayed coking environment. The plastic waste can then be co-processed in the coking environment to generate liquid product.

System and method for co-processing n2o and volatile organic compounds (voc) in waste gasses from caprolactam production

Abstract: A system for co-processing N2O and volatile organic compounds (VOC) in waste gasses from caprolactam production. Based on the flow direction of the waste gasses, the system successively comprises a gas storage apparatus (1), a water scrubber apparatus (3), a gas dilution apparatus, a catalytic reaction apparatus (5), a flue gas monitoring apparatus (6), and an exhaust apparatus. Also disclosed is a method for using said system to co-process N2O and VOC in waste gasses from caprolactam production, wherein the waste gasses from caprolactam production enter the water scrubber apparatus (3) from the gas storage apparatus (1) and enter the catalytic reaction apparatus (5) after preprocessing, a redox reaction occurs under the action of a catalyst, and the product is tested by the flue gas monitoring apparatus (6) for various indicators and is discharged via the exhaust apparatus.

Gasification co-processing method of polymorphic wastes

Abstract: The invention discloses a gasification co-processing method of polymorphic wastes. The method comprises the following steps: (1) respectively crushing feed coal, solid wastes and semi-solid wastes toobtain pulverized coal, solid waste powder and semi-solid waste powder; (2) mixing 50-55 parts by weight of pulverized coal with 20-40 parts by weight of water, adding 0-10 parts by weight of solid waste powder, 0-4 parts by weight of semi-solid waste powder, 0-20 parts by weight of liquid waste and 0.3-0.5 part by weight of an additive, and uniformly mixing and stirring to obtain coal water slurry; and (3) feeding the coal water slurry into a gasification furnace for combustion. According to the invention, polymorphic wastes and pulverized coal are compounded to prepare the coal water slurry,gasification treatment is carried out, the compatibility of different wastes is utilized to improve the dispersibility of the wastes after the wastes are added into the coal water slurry, the fluidity and concentration of the slurry can be ensured, and the stability of project operation is improved; and resource utilization and innocent treatment of waste are realized by treating waste with waste.

Co-processing of plastic waste in a cement kiln: a better option.

Abstract: This paper deals with the techniques to use plastic waste for co-processing in cement kiln for energy recovery. Plastics, a versatile material and friend to the common man, have now become one of the most serious environmental issues when it is discarded into the environment. The focus of this study is on eco-friendly disposal of plastic waste. Plastic is user-friendly, but because of its incomplete lifecycle, it has become a global issue. It is commonly disposed of by land filling or incinerating the waste, which adds to the pollution load at later stages. The authors’ focus is on innovative techniques to use waste plastics in different proportions for the co-processing in cement kiln in order to highlight the energy recovery of the entire plant. It is a good solution to the waste disposal problems that arise due to plastic waste as well as municipal solid waste. The use of plastic waste as an alternative fuel for cement plants is suggested in this paper. The authors also promote this approach and suggest encouraging its calorific value utilization in the cement manufacturing plant. A systematic approach has been presented in this work to mitigate the energy consumption in the cement industries as well as environmental hazards due to plastic and municipal solid waste.

Method for applying red mud in industrial waste gases and wastewater treatment and green high performance functional materials co-processing

Abstract: A method for applying red mud in industrial waste gases and wastewater treatment and green high performance functional materials co-processing, which relates to the technical field of environmental science and cementing material preparation, and in particular relates to a preparation process for a solid waste-based cementing material. The raw material is composed of 10-90 parts of red mud residue after sewage treatment, 20-60 parts of a cementing agent, 2-8 parts of an activator, and 1-5 parts of a toxic element curing agent. A preparation method for red mud residue after sewage treatment is as follows: after carbonizing by passing through industrial tail gas, red mud is prepared into a sewage treating agent, and after sewage is treated, red mud residue after sewage treatment is collected. The red mud residue after sewage treatment alongside other solid waste is prepared into a red mud-based functional building material by means of physicochemical activation and high-temperature calcination. The compressive strength of the prepared solid waste-based cementing material can reach 29 MPa, and the leaching amount of toxic elements, such as heavy metals, of same is less than 3.0 ppm, which is lower than the national regulatory requirement.