Process Technology and Sustainability Assessment of Wastewater Treatment

Abstract

Removal of heavy metals in wastewater treatment is crucial to protect the environment, wildlife, and human health. Various techniques have been developed focusing on removal of heavy metal ions, pharmaceuticals, and other contaminants from different wastewater sources. The main methods include adsorption, filtration, ion exchange, electrochemical, reverse osmosis, precipitation, flotation/coagulation/ flocculation, and photocatalytic-based treatments. This paper comprehensively assesses the sustainability of those common technologies used for wastewater process treatment. The sustainability profile depends mostly on the exact approach followed for each technology, including its energy consumption, type of radiation (where appropriate), auxiliary materials used (e.g., catalysts, adsorbents), and further specific experimental process settings. Thus, while sustainability inevitably provides a multifaceted answer, the review finally aims for sustainability benchmarking of all technologies, by compressing the manifold outcomes toward a compact information set, such as a table and radar plot.

Green industry work: production of FeCl3 from iron and steel industry waste (mill scale) and its use in wastewater treatment

“…Its high efficiency, ease of operation, and low maintenance cost make this method popular today compared to other systems (Teh et al 2016 ). It is convenient for treating industrial wastewaters originating from fields such as the textile, mining, metallurgy, chemistry, and food industries (Zhao et al 2021 ; Tran et al 2023 ). Coagulants such as Al 2 (SO 4 ) 3 , FeCl 3 , Fe 2 (SO 4 ) 3 , PAC, and PAFC are used in the implementation of the process (Verma et al 2012 ).…”

Hydrogen Bond-Induced Activation of Photocatalytic and Piezophotocatalytic Properties in Calcium Nitrate Doped Electrospun PVDF Fibers

“…The results are presented in Figure 4C. The fraction of the electroactive phase was calculated according to Equation (1), where I EA and I 763 are the absorption at 840* and 763 cm −1 , respectively; K 840* and K 763 are the absorption coefficients at the corresponding wave numbers, the values of which were 7.7 × 10 4 and 6.1 × 10 4 cm 2 mol −1 , respectively. Then, using Equation ( 2), the fraction of βand γ-phases in the electroactive phase was calculated: ∆Hβ and ∆Hγ are the height differences (absorption differences) between peaks around 1275 cm −1 and the nearest valley around 1260 cm −1 , and the peak around 1234 cm −1 and the nearest valley around 1225 cm −1 , respectively.…”

“…The pollution of wastewater is a serious problem that affects the health of humans, animals, and the environment. There are many good and highly effective methods of purification [ 1 , 2 , 3 ]; however, environmental requirements and the demand for renewable energy sources bring advanced oxidation processes (AOPs) to the forefront of science, among which photocatalysis, Fenton catalysis, piezocatalysis, pyrocatalysis, sonocatalysis, microbubble ozonation and others are of the greatest interest from both practical and fundamental points of view [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. All these processes are based on the conversion of various types of natural green energy into useful chemical energy.…”

Designing Highly Photoactive Hybrid Aerogels for In-Flow Photocatalytic Contaminant Removal Using Silica-Coated Bacterial Nanocellulose Supports

“…14,15 Additionally, since the fate of nanomaterials and their impact on ecosystems and living beings are still little known, there is a growing environmental concern regarding their possible release into the environment. 16,17 Since these limitations are inherently related to the nanoscale nature of nanomaterials, anchoring or embedding them on/in macroscopic supports or substrates offers a viable and interesting option to design functional nanocomposite materials in suitable forms (membranes, thin film-coated surfaces/beads, and monolithic aerogels 15,18 ) for water treatment applications. Recently, photocatalytic aerogels, especially in monolithic form with macroscopic size and microscopic internal nanostructure, have been successfully used for environmental remediation and energy applications.…”

“…While the small size of photocatalyst NPs renders them with high specific surface area and better photocatalytic efficiencies, the same makes it difficult and time-/energy-consuming to separate such small NPs from colloidal suspension after use. Hence, the use of nanomaterials in particulate/suspension form for real-life applications of water purification or wastewater treatment becomes nearly impractical due to the operational, energy-related, and economic difficulties associated with the management and recovery of nanomaterials. , Additionally, since the fate of nanomaterials and their impact on ecosystems and living beings are still little known, there is a growing environmental concern regarding their possible release into the environment. , Since these limitations are inherently related to the nanoscale nature of nanomaterials, anchoring or embedding them on/in macroscopic supports or substrates offers a viable and interesting option to design functional nanocomposite materials in suitable forms (membranes, thin film-coated surfaces/beads, and monolithic aerogels , ) for water treatment applications.…”