GREYWATER CHARACTERIZATION IN SAUDI ARABIA. Control #: 117

Transcription

1 GREYWATER CHARACTERIZATION IN SAUDI ARABIA Control #: 117

2 AUTHOR A. O. Al-Jasser Associate Professor Civil Engineering Department College of Engineering King Saud University SAUDI ARABIA

3 BACKGROUND

4 Greywater & Blackwater Greywater Is non-industrial wastewater generated from domestic sources such as showers, bathtubs, hand-washing sinks, and washing machines.

5 Greywater Also known as: Graywater Grey water Gray water Are described in to contain low organic matter and pollutants.

6 IMPORTANCE Strategic solutions to limited water supplies in Saudi Arabia and other arid and semi-arid countries : Water conservation, and The use of reclaimed wastewater

7 QUANTITY & USES Represents a substantial fraction of the total domestic wastewater (50-80% of residential wastewater ) May be used for a variety of purposes, including toilet flushing, lawn care and gardening

8 Categories of Greywater High-loaded greywater, and Low-loaded greywater.

9 High-loaded Greywater Is greywater that includes flows from the kitchen, washing machine, and dishwasher.

10 Low-loaded Greywater Represents about 57% of all greywater

11 To Reuse Greywater Greywater and blackwater must be separated in order to reuse water in situ. This requires a dual plumbing system and a treatment unit.

12 Treatment Treatment must reduce contamination to a level that does not: Produce any potential health Environmental risks.

13 EXPERIMENTAL

14 EXPERIMENTAL Nine different sources Forming five categories of domestic sources in Riyadh, Saudi Arabia Characterized with respect to a range of physicochemical and biological parameters.

15 Samples Three typical single-family households with different occupancies. Ablution water from two mosques, A school, A hotel, A labour compound, and A governmental institute.

16 Quality Analysis Sample preservation Parameters studied : ph, turbidity, conductivity, total suspended solids (TSS( TSS), total dissolved solids (TDS( TDS), biochemical oxygen demand (BOD( BOD), chemical oxygen demand (COD), chloride, sulphates (SO 4 ), and fecal coliforms.

17 RESULTS & DISCUSSION

18 Results and Discussion Turbidity For all samples ranged from 21 to 70 NTU. The lowest value was for the governmental institute, whereas the highest value was associated with one of the household and labour compounds

19 Chloride All samples: 146 to 390 mg/l Households only: Chloride : 168 to 188 mg/l (literature: 9.8 to 33.4 mg/l)

20 Sulfates All samples 85 to 498 mg/l High vales are associated with hotel and labour compound. Households only: Sulfates 85 to 199 mg/l (literature: 13 to 145 mg/l)

21 BOD BOD From 3 to 255 mg/l Ablution water from mosques were almost similar to the households.

22 BOD Households: Ranged from 32 to 43 mg/l Literature: 41 to 85 mg/l for a single-family home with two adults, and mg/l for a household occupied by a single family with two adults and one child.

23 COD From 61 to 304 mg/l, Households only: mg/l Literature: 250 to 430 mg/l for greywater, including bath, shower, and washing machines with baby diapers. A low value (58 mg/l) was reported for sink water.

24 Quality Variations Levels of occupancy Source Geographical location Demographics Method of collection Personal habits Climatic conditions Lifestyle.

25 Standards Latest reuse standards for wastewater reuse in agricultural irrigation issued during the year 2006 by the Ministry of Water and Electricity (MWE( MWE). All samples are not suitable for irrigation without any treatment.

26 Reuse Parameter concentrations exceeded the allowable limits for restricted and unrestricted irrigation. Therefore, treatment is needed to harness such water for reuse.

27 Treatment Within household premises, a simple treatment plant can be built to treat the greywater. Storage before treatment must be avoided.

28 Treatment System Modified and constructed. Consists of four processes: 1. Sand trap 2. Storage (also settling, low retention time to avoid septic conditions). 3. An automatic pressure filter 4. Disinfection and storage

29 Treatment Effluent Greywater samples from the two mosques. Treated effluent was suitable for restricted and unrestricted reuse for agricultural irrigation as per the new Saudi Arabian standards for gricultural and landscape irrigation.

30 Tank You