Startseite Technik Real-scale comparison between simple and composite raw sewage sampling
Artikel Open Access

Real-scale comparison between simple and composite raw sewage sampling

  • Paulo Sergio Scalize EMAIL logo und Juliana Moraes Frazão
Veröffentlicht/Copyright: 7. Juni 2018
Veröffentlichen auch Sie bei De Gruyter Brill

Abstract

The present study performed a qualitative and quantitative characterization of the raw sewage collected at the entrance of the sewage treatment station of the city of Itumbiara, state of Goiás. Samples were collected every two hours over a period of seven consecutive days. Characterization of both point samples and composite samples was performed. The parameters analyzed were: temperature, pH, alkalinity, chemical oxygen demand, oil and grease, electric conductivity, total phosphorus, settleable solids, ammoniacal nitrogen, total suspended solids, volatile suspended solids, fixed suspended solids and turbidity. These results allowed us to verify that it is possible to perform the collection and analysis of a point sample, instead of a composite sample, as a way of monitoring the efficiency of a sewage treatment plant.

1 Introduction

The characterization of raw and treated sewage is of paramount importance for verifying the efficiency of the treatment used. However, there are several potentially influential variables from collection to the analytical procedures employed.

According to Leitão (2004), domestic sewage usually varies widely in flow due to the number of inhabitants and residences connected to the sewage network, the specific characteristics of the collection network (type, material, length, maintenance, infiltration and the use of lift stations), as well as climate, topography, domestic and industrial contributions and time. Francisqueto (2007) adds to this group; family income, cultural characteristics of the population and periods of festivals and vacations.

Sperling (1996), considered that between 60% and 100% of the water consumed returns in the form of sewage, and admits a usual coefficient of return of 80%, since part of the water consumed can be incorporated clandestinely into the rainwater network, used in green areas, or infiltrated, among other situations. Metcalf & Eddy (2003) affirm the existence of variation in hourly flow, with the maximum occurring between 7 a.m. and 3 p.m., and the minimum after midnight, inferring that in some cities mean flow values can oscillate between 50% and 200%. Tsutiya (2005) mentions that the volume of sewage produced can range from 50 L.person−1.day−1 to 600 L.person−1.day−1 and is directly related to the volume of water consumed by the population.

Facing this reality, Borges (2005) discusses variation in the organic and hydraulic loads of raw sewage that are sent to Upflow Anaerobic Sludge Blanket (UASB) reactors, because they are perturbation factors that result in the reduction of reactor performance or even in structural failures. Thus, in order to analyze raw sewage, care must be taken to consider the factors responsible for variation in the characteristics of this material, especially when performing composite sampling to represent a whole, further highlighting the use of automatic samplers (PETRIE et al., 2017). Baker & Kasprzyk-Hordern (2011) also point out that for some parameters this type of sampling with this type of sampler, is inadequate, and can influence the results.

The collection and analysis of a composite sample makes it possible to reduce the quantity of samples to be analyzed, since only one sample is needed instead of several simple/point samples collected throughout the period of monitoring. APHA, AWWA & WEF (2005) explain that composite samples should provide a repesentative sample of a group with greater heterogeneity in which the concentration of the analytes of interest can vary over short periods of time. Otherwise, composite camples can be obtained by combining multiple samples or by using automatic sampling devices. According to CETESB (2011), composite samples can not be used for assessing variables that change during aliquot manipulation, citing dissolved oxygen, pH, free carbon dioxide, microorganisms, dissolved metals, volatile compounds and oils and grease, which can be altered (transfer among bottles, volatilization, oxidation and reduction, loss of viability, etc.) during the composition process or during the time period required between collection and analysis. In their study, Hillebrand et al. (2013) concluded that if immediate analysis is not possible, storage time should be minimized. For these situations, simple/point samples can be used, but is of interest to know at what time of day the collection and analysis of simple/point samples would represent the result of the composite sample. According to Ort et al. (2010), a representative sample is a prerequisite for delivering significant analytical results and cannot be compensated for by a large number of samples, accurate chemical analysis or sophisticated statistical evaluation. Thus, the present study aims to characterize raw sewage over a period of seven consecutive days, determine the composite sample and discuss the best time of day for performing simple/punctual sampling aimed at the replacement of the composite sample.

2 Material and methods

The study took place in the municipality of Itumbiara, Goiás, Brazil, and according to data from the local operator, has 19,884 sewer connections, which reach the Estação de Tratamento de Esgoto [Sewage Treatment Station (STS)] - Itumbiara with an average daily flow of 287 L.s−1. The system is composed of three sewage lift stations and a sewage treatment plant with four UASB reactors and five maturation ponds.

According to the characteristics of the system, the study was carried out at the sewage lift station SLS III (Point 2 in Figure 1), where practically all sewage from the city arrives by gravity.

Figure 1 Location of the municipality of Itumbiara. Source: Adapted from www.itumbiara.go.gov.br
Figure 1

Location of the municipality of Itumbiara. Source: Adapted from www.itumbiara.go.gov.br

In order to characterize the raw sewage affluent going to STS - Itumbiara, samples were collected over seven consecutive days at intervals of two hours, generating 84 samples from which the following parameters were analyzed: temperature, pH, alkalinity, chemical oxygen demand (COD), oils and greases (OG), electrical conductivity (EC), total phosphorus (Ptotal), settleable solids (SetS), ammoniacal nitrogen (Nammoniacal), total suspended solids (TSS), volatile suspended solids (VSS), fixed suspended solids (FSS) and turbidity, according to Standard Methods (APHA; AWWA; WEF, 2005), with the exception of the parameter oils and greases (EPA, 1993). The parameter for biochemical oxygen demand (BOD) was not included in the parameters due to the difficulty in carrying out the laboratory analysis within 24 hours. However, this parameter can be estimated as a function of COD as reported in some studies (ORSSATTO et al., 2009; SILVA E MENDONÇA, 2004 & SCALIZE et al., 2003).

Samples were acquired with a 3.5 L container, conditioned in two vials, one of plastic material and the other of amber glass with sulfuric acid (for preservation of the sample), and then packed in a thermal box for transportation to the Laboratório de Saneamento (Laboratory of Sanitation) of UFG, where the physico-chemical analyses were performed (Nammoniacal, Ptotal, OG, COD, TSS, VSS and FSS). The parameters: temperature, alkalinity, SetS, pH, turbidity and EC were analyzed within 90-minutes of collection.

The collection site was at the outlet of the Parshall gutter installed in SLS III, thus the raw sewage was collected almost entirely by gravity, with the exception being that collectionat SLS Dionária Rochaarrived by pumping. At the moment of collection, the flow was recorded using an ultrasonic meter installed in the Parshall gutter in order to determine the composition of the organic load.

The data were collected at intervals of 2 hours (0 to 24 h), and a composite of the values was obtained to acquire a mean for each time interval using Equation 1, where, Q = flow rate (m3.h−1); C = concentration (g.m−3) and M = mean mass of the analyzed parameter (kg.h−1).

Mmedia(02h)=(Q0h×C0h+Q2h×C2h)/(2.1000)(1)

This calculation was performed for the measurements made during the monitoring, from which 12 results were obtained daily for a total of 84 values at the end of the seventh day.

For each time interval (0-2 h; 2-4 h; 4-6 h; …; 22-24 h) mean, minimum and maximum values were obtained analyzing the seven days of the week. The standard deviation and coefficient of variation were then calculated. With these data, graphs were constructed showing the variation over the days of the week and the hours during the day.

3 Results and Discussion

Figure 2 shows that the mean flow rate for the study period was 891.7 m3.h−1 (247.7 L.s−1), with the days of lowest and highest contribution being Monday and Thursday. Figure 2 also shows that the lowest recorded values occurred from 4 h to 6 h and the highest flow from 14 h to 16 h. The sewage flow ranged from 523.8 m3.h−1 to 1,117.1 m3.h−1 and the total volume recorded over the seven days of the study was 149,810 m3.

Figure 2 Variation in sewage flow rate during the study period of seven consecutive days, highlighting the average weekly flow and the average flow during the collection intervals (a), and variation of the sewage flow rate as a function of the monitoring schedule, showing the lowest and highest flow detected (b).
Figure 2

Variation in sewage flow rate during the study period of seven consecutive days, highlighting the average weekly flow and the average flow during the collection intervals (a), and variation of the sewage flow rate as a function of the monitoring schedule, showing the lowest and highest flow detected (b).

The pH values of the 84 simple/point samples varied between 7.16 and 7.67, so that at any time of day the pH value varied little, as was also observed by Souza et al. (2015) in raw sewage from a refectory and toilets sent to a pilot STS.

Considering that the working hours for the majority of the employees of a sanitation company is between 8 h and 16 h, this would be the most suitable time for a possible simple/point sample collection instead of a composite sample. Tables 1 and 2 show the coefficient of variation (CV) for the parameters Nammoniacal, COD, Ptotal, alkalinity, EC, temperature and SetS, which were lower in the range of 8 h to 12 h, being below 10% (with the exception of SetS, which was 14.5%). We can also include in this group of parameters turbidity, which presented a CV of 8.6% within this time interval (8 h to 10 h and 10 h to 12 h). The parameters TSS, VSS, FSS, OG and turbidity had lower CV values between 12 h and 16 h, but the CV values of these parameters, with the exception of turbidity, were higher than 10%, reaching 28.2% in this time interval. For the latter parameters, CV values varied from 6.3% to 70.6%.

Table 1

Values of mean mass, standard deviation and coeflcient of variation for the physico-chemical parameters investigated in raw sewage during the study period, highlighting the lower CV values between 8 h and 15 h.

Time intervalParameter
NammmoniacalCODPtotalAlkalnityECTemprature
Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)
0-227.95.319.1244.034.314.10.35.326.71302.3110.08.4389.929.77.620.91.36.0
2-417.13.621.2129926.920.70.23.620.0958.2124.513.0273.238.714.217.12.011.5
4-638.94.912.6143.534.223.80.24.922.41057.2216.620.5292.948.616.617.50.73.8
6-882.69.711.8321.4139.343.40.59.718.31869.7250.613.4535.488.516.522.52.19.5
8-1092.59.09.7620.4124.820.10.89.017.22508.0210.08.4755.363.48.426.91.66.0
10-1281.211.614.3867.380.69.30.911.67.02498.3177.67.1774.126.33.429.21.03.5
12-1469.511.216.1912.497.010.60.811.27.92304.0175.97.6717.241.85.830.21.55.1
14-1655.57.713.8759.2149.919.70.67.716.81988.0191.19.6626.452.38.328.72.17.3
16-1857.49.216.1636.2117.818.50.69.219.81793.5129.87.2576.129.55.127.42.28.2
18-2061.98.513.7631.966.310.50.68.511.91822.759.53.3591.613.62.327.71.34.7
20-2257.73.56.1587.4142.424.20.63.519.81725.2165.79.6556.035.16.326.51.24.7
22-2445.64.18.9434.397.822.50.44.126.01553.2147.29.5486.729.26.024.01.14.7
  1. CV – coefficient of variation: σ - standard deviation.

Table 2

Values of mean mass, standard deviation and coeflcient of variation for the physico-chemical parameters investigated in raw sewage during the study period, highlighting the lower CV values during the interval of 8 h to 15 h.

Time intervalParameter
SetSTSSVSSFSSOils and greasesTurbidity
Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)Mean mass (kg.h−1)σCV (%)
0-23.00.516.160.615.425.453.014.727.87.62.330.110.30.66.378.07.39.4
2-41.60.530.429.04.616.023.73.816.15.32.852.46.51.319.452.07.113.6
4-61.90.736.360.19.215.351.08.416.59.13.538.912.57.458.846.410.723.0
6-84.70.715.8156.244.928.7133.742.031.422.59.642.732.47.824.296.817.317.8
8-107.61.114.8241.672.830.1206.761.229.635.015.644.652.714.928.3150.518.212.1
10-128.01.214.5270.762.523.1227.156.424.943.714.733.566.817.826.6172.214.78.6
12-148.11.620.2295.754.618.5245.353.321.750.415.029.866.112.619.1173.413.17.6
14-167.81.418.3281.5100.835.8237.791.038.343.812.428.252.58.516.1159.316.210.2
16-185.81.220.6204.286.842.5171.672.142.033.219.558.646.511.825.4143.215.210.6
18-205.31.120.3179.652.529.2154.045.829.726.310.640.242.816.739.1141.911.07.7
20-225.51.629.9178.963.035.2160.057.535.918.910.756.531.36.520.7128.4IS.914.7
22-244.41.227.7124.150.640.8111.343.639.112.79.070.618.53.016.197.714.614.9
  1. CV – coefficient of variation: σ - standard deviation.

Tables 4 to 6 show the calculated values of the physico-chemical parameters studied. Mass values are also included for the time intervals during the seven consecutive days of monitoring. The standard deviation of the means obtained each day Values of CV, calculated by taking into account the weekly average of each parameter, varied between 3.5% and 26.2%. Thus, even if we collect? composite samples for 24 hours, we will have variation among the days of the week.

Table 3

Comparison of the coeflcients of variation obtained in the analyses of the physico-chemical parameters considering the time interval and days of the week.

ParameterCoefficient of variation obtained from the hourly analysis (from Tables 1 and 2)Coefficient of variation obtained from the daily analysis (from Tables 4. 5 and 6)
Ammoniacal nitrogen9.79.1
Chemical oxygen demand9.310.2
Total phosphorus7.07.1
Alkalinity7.13.5
Electrical conductivity3.43.5
Temperature3.53.5
Settleable solids14.59.1
Total suspended solids18.523.8
Volatile suspended solids21.724.9
Fixed suspended solids28.226.2
Oils and greases16.18.9
Turbidity7.67.1

Table 4

Mass of ammoniacal nitrogen, chemical oxygen demand, total phosphorus and alkalinity for the time intervals as a function of the days of the week, with the mean, minimum and maximum mass, plus the standard deviation and CV for the study period.

ParameterTime intervalmass (kg.h−1)
SunMonTueWedThuFriSathourly averagehourly minimumhourly maximum
Ammoniacal nitrogen weekly mean = 57.3kg.h−1; σ=5.2; CV = 9.1%0-233.224.821.521.032.532.529.833.224.821.5
2-420.018.411.012.919.718.818.820.018.411.0
4-631.637.840.044.244.440.633.731.637.840.0
6-874.770.684.599.489.677.482.274.770.684.5
8-1099.976.990.0104.589.489.896.899.976.990.0
10-1298.666.072.288.371.386.086.398.666.072.2
12-1487.654.659.875.664.568.476.187.654.659.8
14-1668.443.853.461.154.552.254.968.443.853.4
16-1865.543.755.272.256.756.851.765.543.755.2
18-2067.047.461.274.963.661.657.467.047.461.2
20-2262.251.356.959.758.855.659.762.251.356.9
22-2451.443.141.140.547.347.748.151.443.141.1
Daily mean63.448.253.962.957.757.358---
Chemical oxygen demand weekly mean = 524 kg.h−1; σ=53.6; CV = 10.2%0-2206235261208302265231244206302
2-48615113111415811315513086158
4-6108136215143139145119143108215
6-8418326486469161214176321161486
8-10736613712778554482468620468778
10-1280080787993010158028398678001015
12-14857765100898010298498999127651029
14-16811623941912825561642759561941
16-18738606684756706443522636443756
18-20658713632584714573550632550714
20-22602865593454640486471587454865
22-24475599404312498406346434312599
Daily mean541537579553562445451---
Total phosphorus weekly mean = 0.53kg.h−1; σ=0.04; CV = 7.1%0-20.230.310.280.200.380.180.320.270.180.38
2-40.130.210.170.130.220.180.190.180.130.22
4-60.160.270.250.150.270.230.220.220.150.27
6-80.310.530.530.580.430.470.500.480.310.58
8-100.600.830.831.000.630.800.840.790.601.00
10-120.830.850.990.940.820.880.930.890.820.99
12-140.820.730.730.890.830.820.880.810.730.89
14-160.600.610.520.830.670.530.680.640.520.83
16-180.620.500.520.630.530.370.700.550.370.70
18-200.470.660.630.580.550.590.670.590.470.67
20-220.450.680.640.430.430.630.590.550.430.68
22-240.530.470.400.240.380.400.580.430.240.58
Daily mean0.480.560.540.550.510.510.59---
Alkalinity weekly mean = 1782 kg.h−1; σ=63.2; CV = 3.5%0-21414130812631131145412271319130211311454
2-4968981836792110090711239587921123
4-674212361321991968886125510577421321
6-81776182222742008179014591958187014592274
8-102684227125382812244922312570250822312812
10-122587232823492714229125232697249822912714
12-142556202022622347216023592423230420202556
14-162285168620961955193620881869198816862285
16-181965163617721746177719731686179316361973
18-201820189418291707187318251810182317071894
20-221782182818771454184115281766172514541877
22-241707158916481304165914031561155313041707
Daily mean1857171718391747177517011836---
  1. CV – coefficient of variation: σ - standard deviation.

Table 5

Mass of electrical conductivity, settleable solids, total suspended solids and volatile suspended solids for the time intervals as a function of the days of the week, with the mean, minimum and maximum mass, plus the standard deviation and CV for the study period.

ParameterTime intervalmass (kg.h−1)
SunMonTueWedThuFriSathourly averagehourly minimumhourly maximum
Electrical conductivity weekly mean = 548 kg.h−1; σ=19.3; CV = 3.5%0-2401387380344441374401390344441
2-4262298234224321258315273224321
4-6225337369278303255284293225369
6-8522562677596529414448535414677
8-10787759815827748648703755648827
10-12772749776823747761791774747823
12-14750638727764692733715717638764
14-16702540660642620634585626540702
16-18616537581593575593537576537616
18-20602608588603592576573592573608
20-22594584566527572493555556493594
22-24514486503445522453485487445522
Daily mean562541573556555516533---
Seatleable solids weekly mean = 5.3kg.h−1; σ=0.5; CV = 9.1%0-23.62.92.22.83.43.22.73.02.23.6
2-42.20.91.21.52.31.61.71.60.92.3
4-61.81.43.32.01.81.11.81.91.13.3
6-84.74.S5.75.54.33.64.24.73.65.7
8-108.48.87.28.97.56.16.57.66.18.9
10-127.68.89.68.17.55.98.58.05.99.6
12-147.28.010.96.18.66.79.28.16.110.9
14-167.76.310.68.67.57.07.07.86.310.6
16-186.03.87.37.35.35.65.65.83.87.3
18-205.15.65.23.47.15.35.65.33.47.1
20-225.38.25.23.57.24.34.85.53.58.2
22-244.96.83.83.45.13.53.64.43.46.8
Daily mean5.45.56.05.15.64.55.1---
Total suspended solids weekly mean = 174 kg.h−1; σ=41.3; CV = 23.8%0-240555886765752614086
2-427272333372530292337
4-652536876645355605276
6-8133145179246136146109156109246
8-10222223252397205223170242170397
10-12254223227402269287233271223402
12-14261227341372336283249296227372
14-16254195400437289209186282186437
16-18219139242367204158100204100367
18-20217132251219181151106180106251
20-22189232280182153110106179106280
22-2499206160143126666912466206
Daily mean164155207247173147122---
Volatile suspended solids weekly mean = 148 kg.h−1; σ=36.9; CV = 24.9%0-230515176664947533076
2-420222223322324242032
4-639465865504949513965
6-81011321472171101389113491217
8-10177205207338170199152207152338
10-12205195189352208231211227189352
12-14212184284340258231210245184340
14-16207158355374235179156238156374
16-181691162273021621349117291302
18-201731112291861491329815498229
20-22165192264164139999716097264
22-2485175149133113596611159175
Daily mean132132182214141127108---
  1. CV – coefficient of variation: σ - standard deviation.

Table 6

Mass of fixed suspended solids, oils and greases, temperature and turbidity for the time intervals as a function of the days of the week, with the mean, minimum and maximum mass, plus the standard deviation and CV for the study period.

ParameterTime intervalmass (kg.h−1)
SunMonTueWedThuFriSathourly averagehourly minimumhourly maximum
Fixed suspended solids weekly mean = 26 kg.h−1; σ=6.7; CV = 26.2%0-21057109748410
2-48529527529
4-613691014479414
6-8321332292681823832
8-1045184559342419351859
10-1249283851625622442262
12-1450435832785339503278
14-1647384663543030443063
16-1850231465422314331465
18-2044212233331912261244
20-22244016181411819840
22-2414311110137313331
Daily mean32232532322115---
Oils and greases weekly mean = 36.6kg.h−1; σ=3.2; CV = 8.9%0-210.611.310.010.39.410.79.710.39.411.3
2-46.34.65.77.26.08.47.66.54.68.4
4-63.95.614.823.87.819.412.312.53.923.8
6-825.333.246.138.523.928.131.632.423.946 1
8-1059.564.572.039.644.230.558.552.730.572.0
10-1284.773.776.563.645.740.183.166.840.184.7
12-1482.065.571.358.748.855.780.566.148.882.0
14-1659.148.458.536.056.550.058.952.536.059.1
16-1842.749.436.455.664.028.649.046.528.664.0
18-2025.445.124.159.868.033.343.642.824.168.0
20-2222.729.725.829.842.435.333.431.322.742.4
22-2420.621.019.612.616.620.418.518.512.621.0
Daily mean36.937.738.436.336.130.040.6---
Tempetature weekly mean = 24.9kg.h−1; σ=0.9; CV = 3.5%0-221.320.620.119.222.920.021.920.919.222.9
2-417.717.414.814.319.017.119.517.114.319.5
4-616.917.118.216.918.617.417.317.516.918.6
6-822.020.325.624.823.320.021.822.520.025.6
8-1027.424.828.028.827.324.527.426.924.528.8
10-1229.727.929.631.128.529.028.829.227.931.1
12-1431.127.631.331.728.931.329.430.227.631.7
14-1630.025.130.331.128.628.927.028.725.131.1
16-1827.924.427.731.328.127.225.327.424.431.3
18-2027.426.128 129.928.627.326.527.726.129.9
20-2227.426.127.926.027.624.625.526.524.627.9
22-2425.223.724.922.825.322.723.324.022.725.3
Daily mean25.323.425.525.725.624.224.5---
Turbidity weekly mean = 120 kg.h−1; σ=8.5; CV = 7.1%0-283.480.272.366.088.179.876.278.066.088.1
2-455.355.754.436.657.353.551.552.036.657.3
4-632.940.165.847.052.139.447.446.432.965.8
6-890.088.8116.2111.9110.667.492.496.867.4116.2
8-10151.4142.3155.1181.6158.9122.1142.5150.5122.1181.6
10-12165.3156.8169.5202.1179.2166.2166.4172.2156.8202.1
12-14172.4150.1178.5183.3190.4174.2164.7173.4150.1190.4
14-16162.8138.5172.2173.5172.6160.1135.1159.3135.1173.5
16-18152.4132.6148.6155.3154.7145.0113.6143.2113.6155.3
18-20148.6143.7147.0139.2156.8135.9122.3141.9122.3156.8
20-22139.5148.5134.1113.8149.3104.8108.8128.4104.8149.3
22-24109.8110.395.283.7117.282.385.597.782.3117.2
Daily mean122.0115.6125.8124.5132.3110.9108.91---
  1. CV – coefficient of variation: σ - standard deviation.

By analyzing the CV values obtained in the hourly and daily analyses (Table 3), it is evident that the variation is very small; that is, the error that may occur by collecting a composite sample on different days of the week is practically the same as that of collecting and analyzing in a determined interval of time.

4 Conclusions

The conclusion of the present study is that the analysis of a composite sample should be performed within a period of at least seven consecutive days, since there is qualitative and quantitative variation among days of the week. In addition, it is possible to collect simple/point samples in substitution for a composite sample for determining the parameters of Nammoniacal, COD, Ptotal, alkalinity, EC, turbidity and temperature with a CV lower than 10%. For the parameters of SetS, TSS, VSS, FSS and OG, the CV was higher than 14.5%, reaching almost 30%. The CV calculated for the different days of the week as a function of the composite samples collected at two-hour intervals is close to the CV obtained from the simple/point samples collected in the pre-established time intervals. The results obtained in this study support the collection and analysis of a simple/point sample in substitution for a composite sample for assessing the studied parameters.

References

APHA, AWWA, WEF, 2005. Standard Methods for the Examination of Water and Wastewater. 21st Ed., Washington, USA.Suche in Google Scholar

Baker, D.R.; Kasprzyk-Horden, B. Critical evaluation of methodology commonly used in sample collection, storage and preparation for the analysis of pharmaceuticals and illicit drugs in surface water and wastewater by solid phase extraction and liquid chromatography-mass spectrometry. Journal of Chromatography A, v. 1218, n. 44, pp. 8036–8059, 2011. http://dx.doi.org/10.1016/j.chroma.2011.09.01210.1016/j.chroma.2011.09.012Suche in Google Scholar PubMed

Borges, R. M. Desenvolvimiento e aplição de um sistema de diagnóstico fuzzy baseado em modelos para reatores UASB tratando esgoto sanitário. Tese. Universidade Federal do Espírito Santo, Centro Tecnológico, 2005.Suche in Google Scholar

Cetesb. Guia nacional de coleta e preservação de amostras: água, sedimento, comunidades aquáticas e efluentes líquidos. Companhia Ambiental do Estado de São Paulo. Organizadores: Carlos Jesus Brandão … [et al.]. São Paulo: CETESB; Brasília: ANA, 326p., 2011.Suche in Google Scholar

Environmental Agency Protection. Domestic Septage Regulatory Guidance: United States Environmental Protection Agency. 1993.Suche in Google Scholar

Francisqueto, L. O. S. Comportamento de reatores UASB frente a varições horárias de vazão de esgoto sanitário. Dissertação. Universidade Federal do Espírito Santo, Centro Tecnológico, 2007.178 p.Suche in Google Scholar

Hillebrand, O.; Musallan, S.; Scherer, L.; Nödler, K.; Licha, T. The challenge of sample-stabilisation in the era of multiresidue analytical methods: a practical guideline for the stabilisation of 46 organic micropollutants in aqueous samples. Science of the total environment, v. 454-455, pp. 289-298, 2013. http://dx.doi.org/10.1016/j.scitotenv.2013.03.02810.1016/j.scitotenv.2013.03.028Suche in Google Scholar PubMed

Leitão R. C. Robustness of UASB reactors treating sewage under tropical conditions. Thesis Wageningen University. 2004.Suche in Google Scholar

Metcalf & Eddy. Wasterwater Engineering: treatment and reuse, 4 ed. New York: Tata McGraw – Hill, 2003.1334 p.Suche in Google Scholar

Orssatto, F. et al. Correlção entre DQO E DBO5 e monitoramento de uma estação de tratamento de esgoto através de técnicas estatísticas de controle de processos. Engenharia Ambiental: Pesquisa e Tecnologia, v. 6, n. 3, p. 155-167, 2009.Suche in Google Scholar

Ort, C.; Lawrence, M. G.; Reungoat, J.; Mueller, J.F. Sampling for PPCPs in wastewater systems: comparison of different sampling modes and optimization strategies. Environmental Science Technology, v. 44, n. 16, p. 6289–6296, 2010. http://dx.doi.org/10.1021/es100778d10.1021/es100778dSuche in Google Scholar PubMed

Petrie, B. et al. Critical evaluation of monitoring strategy for the multi-residue determination of 90 chiral and achiral micropollutants in effluent wastewater. Science of the total environment, v. 9, p. 569-578, 2017. http://dx.doi.org/10.1016/j.scitotenv.2016.11.05910.1016/j.scitotenv.2016.11.059Suche in Google Scholar PubMed

Scalize, P. S. et al. Correlção entre os valores de DBO e DQO no afluente e efluente de duas ETES da cidade de Araraquara. In: Exposição de Experiências Municipais em Saneamento (VIII), Caxias do Sul - RS. 34a. Assembleia Nacional da ASSEMAE, 13 p. 2004.Suche in Google Scholar

Silva, S. R.; Mendonça, A. S. F. Correlção entre DBO e DQO em esgotos domésticos para a região da grande Vitória-ES. Engenharia Sanitária Ambiental, Rio de Janeiro, v. 8, n. 4, p. 213-20, 2003.Suche in Google Scholar

Souza, C. F. et al. Eficiência de estação de tratamento de esgoto doméstico visando reuso agrícola. Revista Ambiente & Água, Taubaté, v. 10, n. 3, p. 587-597, 2015. http://dx.doi.org/10.4136/ambi-agua.154910.4136/ambi-agua.1549Suche in Google Scholar

Sperling, M. Princípios básicos do tratamento de esgotos. Departamento de Engenharia Sanitária e Ambiental, UFMG, Belo Horizonte, Brasil– 1996, 211p.Suche in Google Scholar

Tsutiya, M.T. Abastecimento de Água. 2. Ed. São Paulo. Departamento de Engenharia Hidráulica e Sanitária da escola Politécnica da Universidade de São Paulo, 2005.Suche in Google Scholar

Received: 2017-11-12
Accepted: 2018-04-10
Published Online: 2018-06-07

© 2018 Paulo Sergio Scalize and Juliana Moraes Frazão

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Artikel in diesem Heft

  1. Regular Article
  2. Real-scale comparison between simple and composite raw sewage sampling
  3. 10.1515/eng-2018-0017
  4. The risks associated with falling parts of glazed facades in case of fire
  5. Implementation of high speed machining in thin-walled aircraft integral elements
  6. Evaluating structural crashworthiness and progressive failure of double hull tanker under accidental grounding: bottom raking case
  7. Influence of Silica (SiO2) Loading on the Thermal and Swelling Properties of Hydrogenated-Nitrile-Butadiene-Rubber/Silica (HNBR/Silica) Composites
  8. Statistical Variations and New Correlation Models to Predict the Mechanical Behavior and Ultimate Shear Strength of Gypsum Rock
  9. Analytic approximate solutions to the chemically reactive solute transfer problem with partial slip in the flow of a viscous fluid over an exponentially stretching sheet with suction/blowing
  10. Thermo-mechanical behavior simulation coupled with the hydrostatic-pressure-dependent grain-scale fission gas swelling calculation for a monolithic UMo fuel plate under heterogeneous neutron irradiation
  11. Optimal Auxiliary Functions Method for viscous flow due to a stretching surface with partial slip
  12. Vibrations Analysis of Rectangular Plates with Clamped Corners
  13. Evaluating Lean Performance of Indian Small and Medium Sized Enterprises in Automotive Sector
  14. FPGA–implementation of PID-controller by differential evolution optimization
  15. Thermal properties and morphology of polypropylene based on exfoliated graphite nanoplatelets/nanomagnesium oxide
  16. A computer-based renewable resource management system for a construction company
  17. Hygrothermal Aging of Amine Epoxy: Reversible Static and Fatigue Properties
  18. The selected roof covering technologies in the aspect of their life cycle costs
  19. Influence of insulated glass units thickness and weight reduction on their functional properties
  20. Structural analysis of conditions determining the selection of construction technology for structures in the centres of urban agglomerations
  21. Selection of the optimal solution of acoustic screens in a graphical interpretation of biplot and radar charts method
  22. Subsidy Risk Related to Construction Projects: Seeking Causes
  23. Multidimensional sensitivity study of the fuzzy risk assessment module in the life cycle of building objects
  24. Planning repetitive construction projects considering technological constraints
  25. Identification of risk investment using the risk matrix on railway facilities
  26. Comparison of energy parameters of a centrifugal pump with a multi-piped impeller in cooperation either with an annular channel and a spiral channel
  27. Influence of the contractor’s payment method on the economic effectiveness of the construction project from the contractor’s point of view
  28. Special Issue Automation in Finland
  29. Diagnostics and Identification of Injection Duration of Common Rail Diesel Injectors
  30. An advanced teaching scheme for integrating problem-based learning in control education
  31. A survey of telerobotic surface finishing
  32. Wireless Light-Weight IEC 61850 Based Loss of Mains Protection for Smart Grid
  33. Smart Adaptive Big Data Analysis with Advanced Deep Learning
  34. Topical Issue Desktop Grids for High Performance Computing
  35. A Bitslice Implementation of Anderson’s Attack on A5/1
  36. Efficient Redundancy Techniques in Cloud and Desktop Grid Systems using MAP/G/c-type Queues
  37. Templet Web: the use of volunteer computing approach in PaaS-style cloud
  38. Using virtualization to protect the proprietary material science applications in volunteer computing
  39. Parallel Processing of Images in Mobile Devices using BOINC
  40. “XANSONS for COD”: a new small BOINC project in crystallography
  41. Special Issue on Sustainable Energy, Engineering, Materials and Environment
  42. An experimental study on premixed CNG/H2/CO2 mixture flames
  43. Tidal current energy potential of Nalón river estuary assessment using a high precision flow model
  44. Special Spring Issue 2017
  45. Context Analysis of Customer Requests using a Hybrid Adaptive Neuro Fuzzy Inference System and Hidden Markov Models in the Natural Language Call Routing Problem
  46. Special Issue on Non-ferrous metals and minerals
  47. Study of strength properties of semi-finished products from economically alloyed high-strength aluminium-scandium alloys for application in automobile transport and shipbuilding
  48. Use of Humic Sorbent from Sapropel for Extraction of Palladium Ions from Chloride Solutions
  49. Topical Issue on Mathematical Modelling in Applied Sciences, II
  50. Numerical simulation of two-phase filtration in the near well bore zone
  51. Calculation of 3D Coordinates of a Point on the Basis of a Stereoscopic System
  52. The model of encryption algorithm based on non-positional polynomial notations and constructed on an SP-network
  53. A computational algorithm and the method of determining the temperature field along the length of the rod of variable cross section
  54. ICEUBI2017 - International Congress on Engineering-A Vision for the Future
  55. Use of condensed water from air conditioning systems
  56. Development of a 4 stroke spark ignition opposed piston engine
  57. Development of a Coreless Permanent Magnet Synchronous Motor for a Battery Electric Shell Eco Marathon Prototype Vehicle
  58. Removal of Cr, Cu and Zn from liquid effluents using the fine component of granitic residual soils
  59. A fuzzy reasoning approach to assess innovation risk in ecosystems
  60. Special Issue SEALCONF 2018
  61. Brush seal with thermo-regulating bimetal elements
  62. The CFD simulation of the flow structure in the sewage pump
  63. The investigation of the cavitation processes in the radial labyrinth pump
  64. Testing of the gaskets at liquid nitrogen and ambient temperature
  65. Probabilistic Approach to Determination of Dynamic Characteristics of Automatic Balancing Device
  66. The design method of rubber-metallic expansion joint
  67. The Specific Features of High-Velocity Magnetic Fluid Sealing Complexes
  68. Effect of contact pressure and sliding speed on the friction of polyurethane elastomer (EPUR) during sliding on steel under water wetting conditions
  69. Special Issue on Advance Material
  70. Effect of thermo-mechanical parameters on the mechanical properties of Eurofer97 steel for nuclear applications
  71. Failure prediction of axi-symmetric cup in deep drawing and expansion processes
  72. Characterization of cement composites based on recycled cellulosic waste paper fibres
  73. Innovative Soft Magnetic Composite Materials: Evaluation of magnetic and mechanical properties
  74. Statistical modelling of recrystallization and grain growth phenomena in stainless steels: effect of initial grain size distribution
  75. Annealing effect on microstructure and mechanical properties of Cu-Al alloy subjected to Cryo-ECAP
  76. Influence of heat treatment on corrosion resistance of Mg-Al-Zn alloy processed by severe plastic deformation
  77. The mechanical properties of OFHC copper and CuCrZr alloys after asymmetric rolling at ambient and cryogenic temperatures
Heruntergeladen am 16.12.2025 von https://www.degruyterbrill.com/document/doi/10.1515/eng-2018-0019/html?lang=de
Button zum nach oben scrollen