Pollution reduction at wastewater treatment facilities through thermophilic sludge digestion

2003 ◽  
Vol 48 (3) ◽  
pp. 57-63 ◽  
Author(s):  
J. Zhou ◽  
D.S. Mavinic

Wastewater treatment facilities produce large amounts of sludge, which is a pollutant to the environment if not properly managed. Among the three most common methods (landfills, land application, incineration) of sludge disposal, thermophilic digestion to produce Class-A biosolids for land application is recognized as the most cost-effective, environmentally sustainable option. Full-scale experience revealed that thermophilically digested biosolids consumed a higher dosage of chemicals for conditioning and dewatering than conventionally (mesophilically) digested biosolids. This paper presents findings of a recent study to investigate how major operational parameters affect dewatering properties of thermophilically digested biosolids, and to search for the inter-relationship between digestion, characteristics of digested biosolids, and dewatering properties of thermophilic biosolids. Experimental work was carried out using bench-scale aerobic digesters. This study found that feed sludge composition has a significant effect on dewaterability. A higher content of secondary sludge resulted in poorer dewaterability in undigested and digested sludge. Dewatering properties are sensitive to a temperature effect. Such an effect is physical-chemical in nature. Excessive high shear results in significant deterioration in dewaterability. Thermophilic digestion resulted in a substantial increase in ammonia and phosphate concentrations, but these two factors seem to not have much impact on dewaterability. Instead, cellular biopolymers have a significant role in affecting dewatering properties of thermophilically digested biosolids.

Author(s):  
G. Variushina

Приводятся сведения об условиях формирования, объемах, химическом составе и свойствах осадков очистных сооружений производственных сточных вод автотранспортных предприятий. Даны примеры технологических решений по обезвоживанию образующихся в процессе очистки шламов. Рассмотрены технологические аспекты процесса интенсификации механического обезвоживания уплотненных осадков с использованием высокомолекулярных полиэлектролитов. Представлены данные лабораторных экспериментов по выбору типа флокулянта, его дозы, технологических параметров процесса, а также результаты определения влажности обезвоженных осадков, полученные на модели барабанного вакуум-фильтра. Приведены примеры эффективных обезвоживающих аппаратов отечественного производства и их технические характеристики, рекомендации и критерии их выбора, а также факторы, оказывающие влияние на эксплуатационные параметры обезвоживающего оборудования. Установлено, что наилучшая обезвоживающая способность барабанных вакуум-фильтров (остаточная влажность шламов от 66 до 83) может быть достигнута при применении катионного флокулянта ВПК-402 для осадков различных производственных цехов автотранспортного предприятия.Information on the conditions of generation, volumes, chemical composition and properties of sludge generated at the industrial wastewater treatment facilities of motor transport enterprises is provided. Examples of process engineering solutions for dewatering sludge generated during the wastewater treatment process are given. The technological aspects of enhancing mechanical dewatering of thickened sludge using high-molecular polyelectrolytes are considered. The data of laboratory experiments on choosing the type of flocculant, its dose, technological parameters of the process, as well as the results of determining the moisture content of dewatered sludge obtained in a model of a drum vacuum filter are presented. Examples of effective domestically produced dewatering apparatus and their technical characteristics, recommendations and criteria for their selection, as well as factors influencing the operational parameters of the dewatering equipment are given. It is found that the highest dewatering capacity of drum vacuum filters (residual sludge moisture content from 66 to 83) can be achieved by using VPK-402 cationic flocculant for processing sludge generated at the workshop premises of a motor transport enterprise.


Energies ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 156
Author(s):  
Meryem Hdidou ◽  
Mohamed Chaker Necibi ◽  
Jérôme Labille ◽  
Souad El Hajjaji ◽  
Driss Dhiba ◽  
...  

Located in a semi-arid to arid region, Morocco is confronting increasing water scarcity challenges. In the circular economy paradigm, the reuse of treated wastewater in agriculture is currently considered a possible solution to mitigate water shortage and pollution problems. In recent years, Morocco has made significative progress in urban wastewater treatment under the National Wastewater Program (PNA). However, rural sanitation has undergone significant delays. Therefore, an alternative technology for wastewater treatment and reuse in rural areas is investigated in this review, considering the region’s economic, social, and regulatory characteristics. Constructed wetlands (CWs) are a simple, sustainable, and cost-effective technology that has yet to be fully explored in Morocco. CWs, indeed, appear to be suitable for the treatment and reuse of wastewater in remote rural areas if they can produce effluent that meets the standards of agricultural irrigation. In this review, 29 studies covering 16 countries and different types of wastewater were collected and studied to assess the treatment efficiency of different types of CWs under different design and operational parameters, as well as their potential application in agricultural reuse. The results demonstrated that the removal efficiency of conventional contamination such as organic matter and suspended solids is generally high. CWs also demonstrated a remarkable capacity to remove heavy metals and emerging contaminants such as pharmaceuticals, care products, etc. The removal of microbial contamination, on the other hand, is challenging, and does not satisfy the standards all the time. However, it can be improved using hybrid constructed wetlands or by adding polishing treatment. In addition, several studies reported that CWs managed to produce effluent that met the requirements of wastewater reuse in agriculture of different countries or organisations including Morocco.


2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Ronald J. LeBlanc ◽  
Conrad J. Allain ◽  
Peter J. Laughton

The paper traces the success of a large Canadian wastewater utility that has dealt with the issue of biosolids management and recycling to the extent that it now has more demand for its biosolids than it produces. The Greater Moncton Sewerage Commission's (GMSC) problem is not one of disposing of biosolids, but one of determining which product and uses will be best for the environment as well as being most sustainable and cost effective in the long term. Wastewater treatment and the management of the sludge or biosolids produced are global issues, with growing challenges, that must address the concerns of all of the stakeholders, including the facility administrators and operators, regulators and elected officials, the scientific community, wastewater generators, taxpayers and the general public. The failure to take into consideration the concerns of all of the stakeholders including the lack of meaningful communication with the public has resulted in predictable but preventable problems, including the banning of scientifically acceptable biosolids recycling options in different countries. Consequently, a successful and viable wastewater treatment and biosolids recycling management plan requires a "big picture" view and a sustainable approach, which takes into consideration the concerns of all stakeholders. The paper will deal with key issues to the success of an environmentally sustainable biosolids management programme.


1985 ◽  
Vol 17 (2-3) ◽  
pp. 235-246 ◽  
Author(s):  
A. I. Versprille ◽  
B. Zuurveen ◽  
Th Stein

New acts on wastewater disposal demand for higher process stability and effluent quality. The A-B process, a novel two step treatment system, meets these requirements in a cost effective way. Five full-scale plants have been put in operation over the last two years. The objective of this paper is to give an outline of the features of the A-B system in the context of the results of these full-scale plants. In spite of the extreme high load, the A-stage can be operated at a high reduction rate and is stable. Variations in the organic load and pH- and toxic shocks are leveled out and a constant, mainly soluble effluent is supplied. This implicates a low sludge production in the B-stage. As a consequence higher overall reduction rates are obtained as compared to conventional processes at the same sludge load. Very low and stable final effluent concentrations are observed in all full-scale plants. Of special interest are the possibilities of upgrading existing conventional treatment facilities, at minor costs, by incorporating the A-B technology. The A-B process therefore can be considered as a very promising, cost effective alternative for both existing and new wastewater treatment plants in responding to the increasing effluent demands.


2004 ◽  
Vol 49 (10) ◽  
pp. 155-162 ◽  
Author(s):  
R.J. LeBlanc ◽  
C.J. Allain ◽  
P.J. Laughton ◽  
J.G. Henry

The Greater Moncton Sewerage Commission's 115,000 m3/d advanced, chemically assisted primary wastewater treatment facility located in New Brunswick, Canada, has developed an integrated, long term, sustainable, cost effective programme for the management and beneficial utilization of biosolids from lime stabilized raw sludge. The paper overviews biosolids production, lime stabilization, conveyance, and odour control followed by an indepth discussion of the wastewater sludge as a resource programme, namely: composting, mine site reclamation, landfill cover, land application for agricultural use, tree farming, sod farm base as a soil enrichment, topsoil manufacturing. The paper also addresses the issues of metals, pathogens, organic compounds, the quality control program along with the regulatory requirements. Biosolids capital and operating costs are presented. Research results on removal of metals from primary sludge using a unique biological process known as BIOSOL as developed by the University of Toronto, Canada to remove metals and destroy pathogens are presented. The paper also discusses an ongoing cooperative research project with the Université de Moncton where various mixtures of plant biosolids are composted with low quality soil. Integration, approach to sustainability and “cumulative effects” as part of the overall biosolids management strategy are also discussed.


2019 ◽  
Vol 2 (2) ◽  
pp. 21
Author(s):  
Lindawati Lindawati

Reduction of food rations and shortages is one of the impacts of the increasing human population. Food sector industries then try to cope with the fast growing number of customers. Agribusiness sector gains its popularity in these recent years, including pig farm. The increase trend of animal farming industry is likely to bring increasing pollution problem unless effective treatment methods are used. The main problems related to the pig farm include odor nuisance and pig manure disposal. The existing land application of piggery wastewater is the traditional way to discharge the wastewater. This may yield in land and water contamination, due to the accumulation of unused nutrients by crop plant. A case study of a large commercial pig farm from Australia is proposed to apply in smaller scale in Indonesia. Operational strategies for the small-scale SBR (Sequencing Batch Reactor) treating piggery effluent were developed based on lab-scale experiments. Due to SBR characteristics, which are money-saving and space-saving, it is very suitable to be applied in urban area. An economic evaluation was made of various process options. The cost estimation showed that SBR is a cost effective process, allowing operational batches to be adjusted to reduce unnecessary aeration cost. A reduction in the aeration cost was achieved by shortening the batch time from 24-h to 8-h. A comparison of three different SBR options showed that smaller size reactors could be more flexible and cost effective when compared with the larger ones.


2018 ◽  
Vol 8 (4) ◽  
pp. 777-785
Author(s):  
Mahmudur Rahman Idris ◽  
Md. Arifuzzaman ◽  
Arnob Basak ◽  
Tonmoy Saha and Jarin Yasmin

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