Current status of textile wastewater management practices and effluent characteristics in Tanzania

Abstract Textile wastewater from wet processing units is a major environmental problem. Most chemicals including dyes are only partly consumed, resulting in highly colored wastewater containing a variety of chemicals released into the environment. This paper gives information on the current management of textile wastewater in Tanzania. A semiquantitative analysis was done to identify the main types of chemicals used in wet processing units, wastewater characteristics and existing wastewater treatment methods in the textile industry. The performance evaluation of the existing wastewater treatment plants is also discussed. The advantages of integrating constructed wetlands with the existing treatment facilities for textile wastewater are explained. It has been observed that pretreatment and dying/printing of the fabrics are the main two processes that produce wastewater in many textile companies. Main pollutants are chemicals used from pretreatment and materials removed from de-sizing, bleaching and scouring processes. Dyes, printing pigments and dye auxiliaries are the main pollutants from the dyeing/printing process. Most of the textile companies in Tanzania are equipped with effluent treatment plants. Wastewater treatment plants have basically similar units, which are coagulation-flocculation, sedimentation through clarifiers and aerobic reactor. However, their effluents do not meet discharge limits stipulated by the Tanzania Bureau of Standards (TBS).

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Planning the optimal solution for wastewater management in rural areas - case study

MATEC Web of Conferences ◽

10.1051/matecconf/201817401035 ◽

2018 ◽

Vol 174 ◽

pp. 01035 ◽

Cited By ~ 2

Author(s):

Joanna Boguniewicz-Zablocka ◽

Iwona Klosok-Bazan ◽

Andrea G. Capodaglio ◽

Joanna Ploskonka

Keyword(s):

Wastewater Treatment ◽

Rural Areas ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Optimal Solution ◽

Current Status ◽

Wastewater Management ◽

Collection System ◽

Advantages And Disadvantages

Water management and associated wastewater management is an inseparable element of life and development of modern societies. Collection and treatment of wastewater has a significant impact on the environment and economy, both at the local and global level. It is therefore necessary to proceed to activities that ensure proper wastewater management, especially in rural and low-density areas, where it is necessary to search for optimal solutions with regard to sewage systems, including wastewater treatment plants. One of the solution for wastewater treatment from houses without access to sewerage collection system is the construction of on-site wastewater treatment plants. Construction of on-site wastewater treatment plant poses a number of challenges for municipalities and potential investors and has been discussed by many. Aim of this paper is to draw the current status and perspectives of on-site wastewater treatment systems in Poland, with focus on selected case study from rural areas. The paper presents a way to solve the problem of wastewater management in the municipality of Pietrowice Wielkie using local biological wastewater treatment plants. The article presents technological, technical and economical aspects of the above-mentioned solutions and analysis of the advantages and disadvantages of the system proposed by the municipality.

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Urban Wastewater Treatment in African Countries: Evidence from the Hydroaid Initiative

Sustainability ◽

10.3390/su132212828 ◽

2021 ◽

Vol 13 (22) ◽

pp. 12828

Author(s):

Marco Ravina ◽

Sergio Galletta ◽

Augustin Dagbetin ◽

Omama Ahmed Hussein Kamaleldin ◽

Madalitso Mng’ombe ◽

...

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Current Status ◽

Wastewater Management ◽

African Countries ◽

Training Project ◽

Planning Strategy ◽

The Status ◽

Definition Of ◽

Urban Wastewater Treatment

This study is based on the evidence collected during the “Technical e-Learning Course on Wastewater Treatment”, an international training project developed in 2020 in Italy by the Hydroaid Association, in collaboration with Turin Polytechnic. This work intended to address the sustainability of urban sanitation in various African countries, which the world of international cooperation has been looking at in recent years with growing interest. A comparative analysis of the current strategies and technological solutions was conducted. Data and information reported by the project participants were elaborated and verified. Four African countries—Benin, Egypt, Ethiopia, and Malawi—were considered and two relevant case studies among those proposed by the participants were presented. Starting from this analysis, significant elements about the status and coverage of wastewater management were extracted and reported. The analysis of existing wastewater treatment plants (WWTPs) allowed evaluating their design features and current status of operation. Considerations about the environmental, economic, social, and technical sustainability of wastewater treatment and management were finally reported. Conducting such an analysis provided support in identifying the best practices and the most recurrent problems linked to the various African contexts, which need to be considered for a complete definition of the planning strategy for accessible, efficient, and sustainable sanitation infrastructures.

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Textile Wastewater Reuse: Ozonation of Membrane Concentrated Secondary Effluent

Water Science & Technology ◽

10.2166/wst.1999.0580 ◽

1999 ◽

Vol 40 (4-5) ◽

pp. 99-105 ◽

Cited By ~ 18

Author(s):

A. Lopez ◽

G. Ricco ◽

R. Ciannarella ◽

A. Rozzi ◽

A. C. Di Pinto ◽

...

Keyword(s):

Wastewater Treatment ◽

Acute Toxicity ◽

Wastewater Treatment Plant ◽

Textile Industry ◽

Nonionic Surfactants ◽

Wastewater Reuse ◽

Treatment Plant ◽

Textile Wastewater ◽

Secondary Effluent ◽

Complete Disappearance

Among the activities appointed by the EC research-project “Integrated water recycling and emission abatement in the textile industry” (Contract: ENV4-CT95-0064), the effectiveness of ozone for improving the biotreatability of recalcitrant effluents as well as for removing from them toxic and/or inhibitory pollutants has been evaluated at lab-scale. Real membrane concentrates (pH=7.9; TOC=190 ppm; CDO=595 ppm; BOD5=0 ppm; Conductivity=5,000 μS/cm; Microtox-EC20=34%) produced at Bulgarograsso (Italy) Wastewater Treatment Plant by nanofiltering biologically treated secondary textile effluents, have been treated with ozonated air (O3conc.=12 ppm) over 120 min. The results have indicated that during ozonation, BOD5 increases from 0 to 75 ppm, whereas COD and TOC both decrease by about 50% and 30 % respectively. As for potentially toxic and/or inhibitory pollutants such as dyes, nonionic surfactants and halogenated organics, all measured as sum parameters, removals higher than 90% were achieved as confirmed by the complete disappearance of acute toxicity in the treated streams. The only ozonation byproducts searched for and found were aldehydes whose total amount continuously increased in the first hour from 1.2 up to 11.8 ppm. Among them, formaldehyde, acetaldehyde, glyoxal, propionaldehyde, and butyraldehyde were identified by HPLC.

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Rotating Belt Filters as Enabling Technology for Energy-Neutral Wastewater Treatment Plants: Current Status and Applications

Proceedings of the Water Environment Federation ◽

10.2175/193864715819540847 ◽

2015 ◽

Vol 2015 (13) ◽

pp. 1743-1749 ◽

Cited By ~ 4

Author(s):

Alessandro Franchi ◽

Katrina Williams ◽

Tor Olav Lyng ◽

Wayne Lem ◽

Domenico Santoro

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Current Status ◽

Enabling Technology

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A constructed wetland model for synthetic reactive dye wastewater treatment by narrow-leaved cattails (Typha angustifolia Linn.)

Water Science & Technology ◽

10.2166/wst.2009.500 ◽

2009 ◽

Vol 60 (6) ◽

pp. 1565-1574 ◽

Cited By ~ 18

Author(s):

S. Nilratnisakorn ◽

P. Thiravetyan ◽

W. Nakbanpote

Keyword(s):

Wastewater Treatment ◽

Constructed Wetland ◽

Cell Structure ◽

Salt Content ◽

Textile Wastewater ◽

Reactive Dye ◽

Wastewater Management ◽

Textile Dye ◽

Dye Wastewater ◽

Term Operation

Textile wastewater is contaminated by reactive dye causing unattractive levels of wastewater color, high pH and high salt content when discharged into public water systems. Decolorization of textile wastewater by plant, phytoremediation, is an alternative, sustainable method which is suitable for long term operation. Narrow-leaved cattails are one species of wetland plant with efficiency for decolorizing and remediating textile wastewater. In addition, chemical oxygen demand (COD) can be lowered and dye residue can be removed. The plant also showed a good salt tolerance even after being exposed to a salt solution for 15 days. The narrow-leaved cattails were set up in a constructed wetland model with a vertical flow system operating from bottom to top for synthetic reactive dye wastewater (SRDW) removal. Narrow-leaved cattails could achieve the removal of SRDW at approximately 0.8 gSRDW m−2 day−1. Decolorization of SRDW by this plant was approximately 60%. The advantage of this method is that it is suitable for textile wastewater management and improvement of wetland. These plants could lower COD, remove dye, sodium and total dissolved solids (TDS) whereas other biological and chemical methods could not remove TDS and dye in the same time. These results suggested that the spongy cell structure of this plant has the ability to absorb large amounts of water and nutrients. Physico-chemical analysis revealed increasing amounts of sulfur, silicon, iron and calcium in the plant leafs and roots after exposure to wastewater. Proteins or amide groups in the plant might help in textile dye removal. Regarding decolorization, this plant accumulates dye in the intercellular space and still grows in this SRDW condition. Hence, it can be noted here that narrow-leaved cattails are efficient for textile dye wastewater treatment.

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Clustering of towns and villages for centralized wastewater treatment

Water Science & Technology ◽

10.2166/wst.1995.0408 ◽

1995 ◽

Vol 32 (11) ◽

pp. 85-95 ◽

Cited By ~ 4

Author(s):

Hassaan A. Abd El Gawad ◽

J. H. C. Butter

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Point Of View ◽

Wastewater Management ◽

Specific Situation ◽

Master Plan ◽

Operation Costs ◽

Treatment Technologies ◽

Centralized Wastewater Treatment ◽

Number Of Treatment

In 1993 the Governorate of Fayoum completed its master plan for wastewater management. The master plan presents a staged implementation schedule for the development of wastewater facilities for the Governorate, covering needs up to the year 2020. The targets are ambitious: in order to meet sanitary health standards, nearly two million people (or 60% of the total population) living in 70 towns and villages would need to be served with sewerage systems. Providing all these areas with separate wastewater treatment plants would be impractical. The centralization of treatment at a limited number of treatment plants for clusters of towns and villages has advantages in terms of manageability, cost and environmental protection. In the master plan the configuration of these clusters is presented. For that purpose a stepped approach has been developed: an approach in which aspects such as construction and operation costs of the facilities, existing infrastructure, the geography of the governorate, environmental impact, alternative treatment technologies and phasing of implementation have been considered. An important element of the stepped approach is an analytical model with which - from financial point of view - the optimum size of a cluster can be estimated. Variables of the model are sizes of towns and villages, distances and treatment technologies. The output of the model is a set of general design criteria which has been applied to the specific situation in the governorate. The model has contributed to the establishment of the Master Plan for Wastewater: a plan now used by the Fayoum Sanitation Department as a framework to initiate new projects and to direct the activities of other agencies working in the sanitation sector in the governorate.

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Textile Wastewater Treatment on a Spinning Disc Reactor: Characteristics, Performances, and Empirical Modeling

Applied Sciences ◽

10.3390/app10238687 ◽

2020 ◽

Vol 10 (23) ◽

pp. 8687

Author(s):

Eugenia Teodora Iacob Tudose ◽

Carmen Zaharia

Keyword(s):

Wastewater Treatment ◽

Suspended Solids ◽

Operating Time ◽

Textile Wastewater ◽

Empirical Modeling ◽

Effluent Treatment ◽

Suitable Alternative ◽

Additional Processing ◽

Textile Wastewater Treatment ◽

Spinning Disc

Spinning disc (SD) technology has been successfully applied, for the first time, in real textile wastewater treatment with no other additional processing. The SD efficiency was investigated using real textile effluents to study the color and suspended solids removals at different effluent-supplying flowrates (10–30 L/h) and different disc rotational speeds (100–1500 rpm) with good experimental results; thus, it can minimize the polluting loads within a short time period. Furthermore, within this study, process modeling and its classical optimization were applied to SD technology for wastewater treatment. The experiments were organized according to an active central composite rotatable 23 order design, considering as independent variables the wastewater flowrate, rotational speed, and operating time and, as optimization criteria, the suspended solids removal and discoloration degree. Overall, this novel study proved that the SD technology applied in textile effluent treatment is a suitable alternative to a primary mechanical step.

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A review on the sustainability of textile industries wastewater with and without treatment methodologies

Reviews on Environmental Health ◽

10.1515/reveh-2018-0013 ◽

2018 ◽

Vol 33 (2) ◽

pp. 163-203 ◽

Cited By ~ 17

Author(s):

Punyasloka Pattnaik ◽

G.S. Dangayach ◽

Awadhesh Kumar Bhardwaj

Keyword(s):

Textile Industry ◽

Global Economy ◽

Liquid Waste ◽

Textile Wastewater ◽

Alternative Methods ◽

Wastewater Management ◽

Low Grade ◽

Efficient Treatment ◽

Treatment Techniques ◽

Textile Industries

Abstract The textile industry in India plays a vital role in the economic growth of the nation. The growth of the textile industry not only impacts the economy of a country but also influences the global economy and mutual exchange of technology between the countries. However, the textile industry also generates an enormous quantity of waste as waste sludge, fibers and chemically polluted waters. The chemically polluted textile wastewater degrades the quality of the soil and water when it mixes with these natural resources and its dependent habitats and environment. Owing to the existing problem of solid and liquid waste, textile industries are facing major problems in environment pollution. Therefore, researchers and the textile industries are focusing on the reduction of textile wastewater and the formulation of alternative efficient treatment techniques without hampering the environment. Hence, the present literature survey mainly concentrates on the various wastewater treatment techniques and their advantages. Moreover, the focus of the study was to describe the methods for the reduction of environmental waste and effective utilization of recycled water with zero wastewater management techniques. The alternative methods for the reduction of textile waste are also covered in this investigation. Finally, this paper also suggests utilization of solid wastes after treatment of wastewater in other sectors like construction for the preparation of low-grade tiles and or bricks by replacing the cement normally used in their manufacturing.

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Cost of Urban Wastewater Treatment and Ecotaxes: Evidence from Municipalities in Southern Europe

Water ◽

10.3390/w11030423 ◽

2019 ◽

Vol 11 (3) ◽

pp. 423 ◽

Cited By ~ 1

Author(s):

Encarnación Moral Pajares ◽

Leticia Gallego Valero ◽

Isabel Román Sánchez

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Methodological Approach ◽

Economic Feasibility ◽

Wastewater Management ◽

Management Service ◽

Southern Europe ◽

Urban Wastewater ◽

Urban Wastewater Treatment

The principle of cost recovery established by the Water Framework Directive underlines the need for tax rates, which can raise enough revenue to finance the cost of treatments applied to wastewater. The objective of this research is to gain an understanding the different types of charges related to urban wastewater treatment that can be levied by the authorities responsible for this service. This paper also aims to determine whether these taxes contribute to guaranteeing the economic feasibility of the wastewater treatment plants. The proposed methodological approach is applied to 18 municipalities of a province in southern Europe in 2017. The results confirm that in most of these cases, the taxes levied do not guarantee adequate tax revenues to cover the running, maintenance and investment costs of municipal wastewater treatment plants. This situation leads to a lack of financial self-sufficiency in the wastewater management service, meaning that the imbalance between income and expenditure has to be covered by government subsidies. The results of this study will help guide authorities around the world that are in charge of managing urban wastewater treatment services.

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