Sustainable biogas mitigation and value-added resources recovery using methanotrophs intergrated into wastewater treatment plants

Sludge is a by-product of municipal wastewater treatment plants (WWTPs) and its management contributes significantly to the operating costs. Large WWTPs usually have anaerobic sludge digesters to valorize sludge as methane and to reduce its mass. However, the low methane market price opens the possibility for generating other high value-added products from the organic matter in sludge, such as polyhydroxyalkanoates (PHAs). In this work, the economic feasibility of retrofitting two types of WWTPs to convert them into biofactories of crude PHAs was studied. Two cases were analyzed: (a) a large WWTP with anaerobic sludge digestion; and (b) a small WWTP where sludge is only dewatered. In a two-stage PHA-production system (biomass enrichment plus PHAs accumulation), the minimum PHAs cost would be 1.26 and 2.26 US$/kg PHA-crude for the large and small WWTPs, respectively. In a single-stage process, where a fraction of the secondary sludge (25%) is directly used to accumulate PHAs, the production costs would decrease by around 15.9% (small WWTPs) and 19.0% (large WWTPs), since capital costs associated with bioreactors decrease. Sensitivity analysis showed that the PHA/COD (Chemical Oxygen Demand) yield is the most crucial parameter affecting the production costs. The energy, methane, and sludge management prices also have an essential effect on the production costs, and their effect depends on the WWTP’s size.

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Rethinking urban water systems – revisiting concepts in urban wastewater collection and treatment to ensure infrastructure sustainability

Water Science & Technology Water Supply ◽

10.2166/ws.2005.0031 ◽

2005 ◽

Vol 5 (2) ◽

pp. 145-154 ◽

Cited By ~ 7

Author(s):

G. Tjandraatmadja ◽

S. Burn ◽

M. McLaughlin ◽

T. Biswas

Keyword(s):

Wastewater Treatment ◽

Water Reuse ◽

Economies Of Scale ◽

Wastewater Treatment Plants ◽

New Technology ◽

Liquid Waste ◽

Value Added ◽

Population Expansion ◽

Sustainable Solutions ◽

Wastewater Collection

Technology and economic development has led to the growth of megacities and urban centres with populations in the millions. Such population expansion and densification increases the strain on wastewater collection and treatment infrastructure, which has been largely based on an end-of-line centralised model. However, in megacities new challenges arise, because provision of suitable sanitation is expensive and it requires infrastructure expansion through construction of extensive sewer networks and larger capacity wastewater treatment plants, which consume more energy. Alternative disposal techniques for solid and liquid waste generated during the treatment process are required, because disposal solutions are decreasing as landfill costs rise and environmental standards are tightened, the latter reducing opportunities for land reuse. Additionally, mass wastewater discharge can have a detrimental impact on the ecology of water bodies and on the health of downstream populations, and requires suitable treatment before disposal. These challenges have the potential to offset the savings that the economies of scale offered by the traditional wastewater collection and treatment systems can impart. The need for affordable and effective wastewater systems in megacities requires the re-evaluation of traditional systems and the re-engineering of water and wastewater transport and resource concepts. Alternative concepts in wastewater collection and treatment, such as decentralised treatment, allied with innovative solutions using current and new technology could play a role in providing affordable and sustainable solutions to deal with the wastewater issue. This paper investigates the scope that integrated wastewater treatment and localised water reuse (in-line treatment, sewer mining), resource recovery (biogas, biosolids), operational changes (timed discharge of sewers, vacuum sewers) and biotreatment (e.g. vermiculture, faecal coliform removal) can play to guarantee the longevity of wastewater infrastructure in megacities. These alternatives offer increased treatment efficiency, recovery of value-added products, and reduce infrastructure cost, whilst maintaining health standards and reducing environmental discharge.

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Value-added innovation in infrastructure systems, lessons learned from wastewater treatment plants

The TQM Journal ◽

10.1108/tqm-11-2018-0178 ◽

2019 ◽

Vol 31 (6) ◽

pp. 1049-1063 ◽

Cited By ~ 2

Author(s):

Shervin Jamshidi

Keyword(s):

Wastewater Treatment ◽

Quality Management ◽

Wastewater Treatment Plants ◽

Value Added ◽

Green Energy ◽

Shared Values ◽

Service Industries ◽

Organic Fertilizers ◽

Content Type ◽

Managerial System

PurposeWastewater treatment plants (WWTPs) are evolving toward sustainability. The purpose of this paper is to discuss how innovation can develop these mission-based service industries to value-added manufacturing enterprises. Here, innovation is embedded in altering the understanding of stakeholders toward the objectives and managerial systems of these infrastructures.Design/methodology/approachThis study uses multidisciplinary principles in management, economics and engineering to assess the integration of innovation and quality management with different perspectives. It initially compares the conventional and innovative approach for operating WWTPs. Subsequently, it emphasizes the contribution of the tailor-made managerial system of wastewater treatment enterprises through prospective markets, customers’ preferences, probable competitions and shared values.FindingsThe tailor-made managerial system for wastewater treatment can add economic values by manufacturing multiple demand products for local markets. Water, green energy, organic fertilizers and raw materials are the main products that can be simultaneously recovered according to the customers’ demand. The Kano model also verifies that the new managerial system has this potential to turn the conventional must-be treatment systems into delightful enterprises. It can provide different stakeholders with shared social and environmental values. Accordingly, locals and customers can be engaged in monitoring the quality of products to consider their feedback for decision making and upgrading. This indirectly defines shared values among operators and society to reinforce localization and ecosystem protection. Additionally, this research reveals that the market of the aforementioned strategic products is promising as a blue ocean for set sail due to the lack of competitors.Originality/valueThis study introduces wastewater treatment as a promising enterprise for integrating innovation and quality management.

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Analysis and balance of phosphorous removal from wastewater at urban wastewater treatment plant

Pollack Periodica ◽

10.1556/606.2020.15.2.13 ◽

2020 ◽

Vol 15 (2) ◽

pp. 142-151

Author(s):

Peter Lukac ◽

Lubos Jurik

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Wastewater Treatment Plants ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Phosphorus Recovery ◽

Anaerobic Sludge ◽

Biological Phosphorus Removal ◽

The Mean

Abstract:Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.

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