Tag Archives: wastewater treatment

1082-1092 V. Denisova, K. Kokina, K. Gruskevica and L. Mezule
Simultaneous nutrient and organic matter removal from wastewater by aerobic granular sludge process
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Simultaneous nutrient and organic matter removal from wastewater by aerobic granular sludge process

V. Denisova*, K. Kokina, K. Gruskevica and L. Mezule

Riga Technical University, Faculty of Civil Engineering, Water Research and Environmental Biotechnology Laboratory, Kipsalas 6a, LV-1048, Riga, Latvia
*Correspondence: viktorija.denisova@rtu.lv

Abstract:

Aerobic granular sludge (AGS) technology offers several benefits, such as simultaneous removal of nutrients and organic matter from wastewater, stronger granule structure, excellent settleability, and high resistance to toxicity. However, the formation of granules can take a long time and needs to be dense and stable.

In this study, the formation of aerobic granules in sequencing batch reactors (SBRs) using a granular activated carbon (GAC) and aluminium sulphate coagulant were evaluated for the simultaneous removal of nutrient (phosphorus (TP) and nitrogen (TN)) and organic matter (chemical oxygen demand (COD)) from wastewater. The reactors were continuously operated for 107 days and were fed with synthetic media and real domestic sewage. However, adaptation process with the synthetic wastewater led to relatively slow granulation process (sedimentation rate of sludge flocks was 3 m h-1). During the experiments, there was no visible formation of granules in SBRs based on the analysis of the sludge samples, only the formation of aggregate structures similar to flocks. However, the results showed that total phosphorus (TP) removal efficiency was over 90% in SBR operated with aluminium sulphate. However, COD and total nitrogen (TN) removals were higher in GAC SBR, 75% and 10%, respectively. Thus, even if granules are not developed yet, the system is working efficiently. The results of this study could be useful in the development of AGS technology for full-scale wastewater treatment plant.

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1161-1173 J. Karasa, R. Ozola-Davidane, K. Gruskevica, L.I. Mikosa, J. Kostjukovs, S. Kostjukova, I. Zekker and A.E. Krauklis
Use of calcium/iron oxide composites for sorption of phosphorus from wastewater
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Use of calcium/iron oxide composites for sorption of phosphorus from wastewater

J. Karasa¹, R. Ozola-Davidane¹*, K. Gruskevica², L.I. Mikosa², J. Kostjukovs¹, S. Kostjukova³, I. Zekker⁴ and A.E. Krauklis¹

¹University of Latvia, Faculty of Geography and Earth Sciences, Department of Environmental Protection, Jelgavas street 1, LV-1004 Riga, Latvia
²Riga Technical University, Research Centre for Civil Engineering, Water Research Laboratory, P. Valdena 1-204, LV-1048 Riga, Latvia
³Ltd. P-AGRO minerals, Plavas street 1, LV-3801 Saldus, Latvia
⁴University of Tartu, Faculty of Science and Technology, Institute of Chemistry,
Chair of Colloidal and Environmental Chemistry, Ravila 14a, 50411 Tartu, Estonia
*Correspondence: ruta.ozola-davidane@lu.lv

Abstract:

The development of an effective, low-cost and natural sorbent is of great significance for phosphorus removal and recovery from small and medium size industrial and municipal wastewater. Commonly used phosphorus removal methods are costly and thus rarely applied in the small-scale WWTPs. This research was aimed at preparing and characterising three different calcium/iron composites for evaluating their sorption performance for the removal of phosphorus from aqueous solutions and domestic wastewater. The obtained composite materials belonging to the Brownmillerite mineralogical subgroup were characterised by the Powder X-ray Diffraction (PXRD), specific surface area analysis by Brunauer-Emmett-Teller (BET) method and scanning electron microscope (SEM). It was found that for aqueous solutions the sorption process is pH- dependent, showing the optimal sorption conditions for phosphorus removal at pH 3 to pH 6. However, all three proposed composites significantly increased the pH of wastewater. All three tested materials adsorbed phosphorus from wastewater. Maximal phosphorus adsorption capacity from the domestic wastewater was 17.75 mg g–1, 8.25 mg g-1 and 4.46 mg g-1 for CaFeOxide, CaFeHydr and CaFeReg respectively. In further research it is planned to develop an environmentally friendly and cost-effective phosphorus recovery technology with the potential to apply the used sorbent as a slow-release fertiliser in agriculture.

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1216–1226 K. Tihomirova, V. Denisova, K. Golovko, O. Kirilina–Gutmane, L. Mezule and T. Juhna
Management of wastewater from landfill of inorganic fiberglass
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Management of wastewater from landfill of inorganic fiberglass

K. Tihomirova¹²*, V. Denisova¹, K. Golovko¹, O. Kirilina–Gutmane², L. Mezule¹ and T. Juhna¹

¹Riga Technical University, Faculty of Civil Engineering, Research Centre for Civil Engineering, Water Research Laboratory, Kipsalas 6a–263, LV–1048 Riga, Latvia
²The Institute of Food Safety, Animal Health and Environment ‘BIOR’ Elemental analysis division, Lejupes street 3, LV–1076 Riga, Latvia
*Correspondence: kristina.tihomirova@rtu.lv

Abstract:

Sustainability is one of the key factors in smart environment management and include the reduction of environment footprint. The waste and wastewater management plans are aimed on actions to reduce the amount of waste and environmental pollution. This includes collection of waste, logistics, storage, processing or valorisation and also treatment. The aim of this research was to evaluate environmental pollution risk and to demonstrate one of the wastewater management schemes to reduce the pollution level.
Evaluation of the better management scheme was performed in one of the landfills in Latvia, where fiberglass waste and other inorganic waste is stored. Onsite evaluation results demonstrated the need to develop a better wastewater management scheme of inorganic fiberglass landfill. After that, laboratory–scale experiments for conventional coagulation and biodegradation tests have been performed for efficient management.

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490–500 J. Nagy and A. Zseni
Human urine as an efficient fertilizer product in agriculture
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Human urine as an efficient fertilizer product in agriculture

J. Nagy¹* and A. Zseni²

¹Széchenyi István University, Faculty of Mechanical, Informatics and Electrical Engineering, Department of Applied Mechanics, Egyetem tér 1. HU9026 Győr, Hungary
²Széchenyi István University, Audi Hungaria Faculty of Automotive Engineering, Department of Environmental Engineering, Egyetem tér 1. HU9026 Győr, Hungary
*Correspondence: nagyju@sze.hu

Abstract:

Flush toilet based water infrastructure, which handles blackwater and greywater together, causes a lot of environmental problems. Among these, the loss of valuable organic material and nutrient content of human excreta (faeces and urine) is not sufficiently emphasized yet. Utilization of human excreta for agricultural purposes is based on the separate collection of greywater and human excreta. As urine contains most of the nutrients of human excreta, researches focus mainly on urine’s treatment and utilization for agricultural purposes. We reviewed the data in literature about the nutrient content of human excreta. In this paper we present the content of macro and microelements of human urine to show its potential value as a fertilizer. To confirm the necessity of urine’s utilization in agriculture instead of treated it by traditional waste water treatment methods, we have collected and compared the most important advantages and disadvantages of traditional wastewater treatment, separated handling of greywater and excreta as well as human urine’s agricultural utilization.

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