Performance study on organic carbon, total nitrogen, suspended solids removal and biogas production in hybrid UASB reactor treating real slaughterhouse wastewater

In this work the performance of an anaerobic UASB reactor coupled with an activated sludge reactor for carbon and nitrogen removal in slaughterhouse wastewater is investigated. Periods with and without recirculation of aerobic effluent over 165 days are analysed. Working with a recirculation ratio of 2, removal efficiencies up to 90% and 65% are obtained for DQO and total nitrogen (TN), respectively. Higher recirculation ratios caused severe washout of active biomass in both reactors due to the high hydraulic loading rates applied. Denitrification in the UASB reactor was complete, with no nitrite accumulation and mainly to nitrogen gas. Significant decreases in COD removal efficiencies in the UASB reactor were observed at recirculation ratio of 2. Sudden decreases in total nitrogen efficiencies were related to inhibition process of nitrifying microorganisms, especially at high recirculation ratios.

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Influence of Pre-Hydrolysis on Sewage Treatment in an Up-Flow Anaerobic Sludge BLANKET (UASB) Reactor: A Review

Water ◽

10.3390/w11020372 ◽

2019 ◽

Vol 11 (2) ◽

pp. 372 ◽

Cited By ~ 5

Author(s):

Rajinikanth Rajagopal ◽

Mahbuboor Choudhury ◽

Nawrin Anwar ◽

Bernard Goyette ◽

Md. Rahaman

Keyword(s):

Suspended Solids ◽

Biogas Production ◽

Sewage Treatment ◽

Oxygen Demand ◽

High Rate ◽

Uasb Reactor ◽

Organic Loading Rate ◽

Anaerobic Sludge ◽

Two Phase ◽

Anaerobic Sludge Blanket

The up-flow anaerobic sludge blanket (UASB) process has emerged as a promising high-rate anaerobic digestion technology for the treatment of low- to high-strength soluble and complex wastewaters. Sewage, a complex wastewater, contains 30–70% particulate chemical oxygen demand (CODP). These particulate organics degrade at a slower rate than the soluble organics found in sewage. Accumulation of non-degraded suspended solids can lead to a reduction of active biomass in the reactor and hence a deterioration in its performance in terms of acid accumulation and poor biogas production. Hydrolysis of the CODP in sewage prior to UASB reactor will ensure an increased organic loading rate and better UASB performance. While single-stage UASB reactors have been studied extensively, the two-phase full-scale treatment approach (i.e., a hydrolysis unit followed by an UASB reactor) has still not yet been commercialized worldwide. The concept of treating sewage containing particulate organics via a two-phase approach involves first hydrolyzing and acidifying the volatile suspended solids without losing carbon (as methane) in the first reactor and then treating the soluble sewage in the UASB reactor. This work reviews the available literature to outline critical findings related to the treatment of sewage with and without hydrolysis before the UASB reactor.

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Effect of Hydraulic Retention Time on the Treatment of Real Cattle Slaughterhouse Wastewater and Biogas Production from HUASB Reactor

Water ◽

10.3390/w12020490 ◽

2020 ◽

Vol 12 (2) ◽

pp. 490

Author(s):

Mohammed Ali Musa ◽

Syazwani Idrus

Keyword(s):

Retention Time ◽

Suspended Solids ◽

Hydraulic Retention Time ◽

Biogas Production ◽

Nitrogen Concentration ◽

Upflow Anaerobic Sludge Blanket ◽

Synthetic Wastewater ◽

Growth Surface ◽

Anaerobic Sludge ◽

Slaughterhouse Wastewater

Anaerobic digestion technology provides an alternative route for sustainable management of organic waste. In this study, the performance of the hybrid upflow anaerobic sludge blanket (HUASB) reactor consisting of synthetic grass media as attached growth surface was investigated for the treatment of cattle slaughterhouse wastewater under mesophilic (35 ± 1 °C) condition. After acclimatization with synthetic wastewater, the reactor was loaded up to OLR 10 g L−1d−1, corresponding to 20 g COD/L at a varying hydraulic retention time (HRT) of 24, 30, 36, 42, and 48 h. The system attained a maximum COD removal efficiency of 97% total suspended solids (TSS), volatile suspended solids (VSS), fats, oil, and grease (FOG), color removal, and turbidity were found as 97%, 284 mg/L, 79%, 78%, and 91% respectively. The biogas production after 48 h was found as 38 L/d, with about 85% methane and specific methane production of 0.24 LCH4/gCODadded. The ratio of alkalinity was 0.22, while ammonia nitrogen concentration reached a maximum of 839 mg/L at a steady state. Scanning electron microscopic (SEM) analysis revealed a predominance of Methanosarcina bacteria with the coccoidal shape at the end of the performance study. Therefore, the results of the experiment showed that increasing HRT significantly affects the performance of the system.

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Impact of Irrigational Runoff on Fish Biodiversity in River Ngadda, Maiduguri – Borno State

Nigerian Journal of Pure and Applied Sciences ◽

10.48198/njpas/20.b04 ◽

2021 ◽

pp. 3981-3988

Author(s):

Mathias Nzitiri Bwala

Keyword(s):

Organic Carbon ◽

Total Organic Carbon ◽

Total Nitrogen ◽

Suspended Solids ◽

Total Suspended Solids ◽

Total Dissolved Solids ◽

Chemical Parameters ◽

Dissolved Solids ◽

Fish Biodiversity ◽

Physico Chemical

Irrigation is a dry season agricultural activity that was known to man for centuries. Agricultural runoff has been identified as the major nonpoint sources of pollution into surface waterbodies which changes the physico – chemical parameters thereby impacting on the biodiversity of such ecosystem. River Ngadda receives pollutants from the irrigational sites along the river bank. The study was aimed at assessing the impact of irrigation on fish biodiversity in river Ngadda, Maiduguri, Borno State, Nigeria. The objectives of the study were to determine the physico – chemical parameters and examine the fish biodiversity of the river. The river was divided into 4 sampling Stations. Water samples was collected biweekly for the period of 6 months from 4 sampling stations. The physico – chemical qualities (total nitrogen (TN), ammonium (NH4+), total phosphorus (TP), total organic carbon (TOC), total dissolved solids (TDS), turbidity (Tur) and total suspended solids (TSS) were determined using standard methods. Capture and recapture method was employed to determine the relative abundance of fish species using Lincoln index. The mean Total Nitrogen (TN) ranges from 5.02 mg/L – 8.31mg/L, mean ammonium (NH4+) ranges from 0.93mg/L – 2.01, mean Total phosphorous (TP) ranges from 0.07mg/L – 1.81mg/L. mean Total Organic Carbon (TOC) ranges 5.87mg/L – 7.45mg/L, mean Turbidity (Tur) ranges from 27mg/L – 31mg/L, mean Total Dissolved Solids (TDS) ranges 198NTU – 298NTU, mean Total Suspended Solids ranges from 34mg/L – 47mg/L and mean surface water Temperature ranges from 26°C – 28°C. A total of 4 families and 10 species of fishes were identified in the sampling stations.

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Field-Scale Studies of Subsurface Flow Constructed Wetlands for Stormwater Quality Enhancement

Water Quality Research Journal ◽

10.2166/wqrj.1997.008 ◽

1997 ◽

Vol 32 (1) ◽

pp. 101-118 ◽

Cited By ~ 6

Author(s):

Q.J. ROCHFORT ◽

W.E. Watt ◽

J. Marsalek ◽

B.C. Anderson ◽

A.A. Crowder

Keyword(s):

Organic Carbon ◽

Constructed Wetlands ◽

Suspended Solids ◽

Nutrient Loading ◽

Subsurface Flow ◽

Reaction Rates ◽

Pollutant Removal ◽

Order Kinetic ◽

Dissolved Metals ◽

Subsurface Flow Constructed Wetlands

Abstract Two subsurface flow constructed wetlands were tested for pollutant removal performance in conjunction with an on-line stormwater detention pond, in Kingston Township, Ontario. The 4.9 m2 wetland cells were filled with 9 mm limestone gravel, and planted with cattail, common reed and spike rush. Changes in nutrient (total organic carbon, PO43- and NH4+), suspended solids and metal (Cu, Pb, Zn) concentrations were used to assess performance. Contaminant removal occurred through a combination of physical, chemical and biological means. As with any biological system, variation in performance of stormwater wetlands can be expected to occur as a result of fluctuations in contaminant loading, contact time and ambient environmental conditions. Storm pond effluent was delivered in continuous flow through the wetlands (during baseflow and event conditions), with a detention time of 1 to 3 days. The wetlands were able to maintain removal rates of up to 39% for orthophosphate even during the more severe conditions of fall dieback. Average removal of suspended solids (46%) and dissolved metals (Cu 50%) remained similar throughout all tests. Organic carbon was reduced by less than 10% during these tests. Low nutrient levels in the pond effluent were supplemented by spiking with sources of carbon, nitrogen and phosphorus during pulsed loading conditions. Daily sampling produced a time series, which illustrated the rates of decline in concentration of nutrients. First order kinetic assimilation rates ranged from 1.7 d-1 for NH4002B to 0.12 d-1 for organic carbon, which were noticeably lower when compared with municipal and industrial wastewater treatment rates. Three methods of sizing stormwater wetlands (impervious surface area, volumetric load and kinetic reaction rates) were compared using the same design storm and data from this study. From this comparison it was seen that the kinetic sizing approach proved to be the most versatile, and allowed for adaptation to northern climatic conditions and anticipated nutrient loading.

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