Assessment of Foreign Material Load in the Management of Faecal Sludge in the Greater Accra Region of Ghana

Abstract

Faecal sludge management has been a burden for most waste managers particularly in developing countries; yet a sure way of preventing the continuous disposal of this waste into drains, bushes water bodies and the environs in general has been by treatment. The introduction of a new treatment plant with the UASB technology in the management process of faecal sludge has been much welcomed as an improved technology for solving the treatment problems of the waste; but this technology is not without some challenges. It has no design criteria for the treatment of other wastes that it screens from faecal sludge. This paper assessed the foreign material load in faecal sludge dislodged at the treatment plant at the Lavender hill a suburb of the Greater Accra region of Ghana. The foreign materials in the faecal sludge were categorized into their material composition or items that were relatively easy to recognized. The characteristic components were Textile/Fabric, Condoms, Gravels, Metal, Glass, Sanitary pads, Rubber/Plastics and Others' (cotton wool, mobile phones, broom sticks, paper wrappers, cartons, wallets, ID cards, money, feotus). The faecal sludge of Greater Accra region of Ghana contains about 0.24kg of foreign materials per cubic metre of the faecal sludge. Of this composition, the highest contribution was seen to have come from plastics contributing about 36.80%. Sanitary pads, textiles, 'others' category, condoms, stones, metals and glasses respectively contributing 29.89%,18.55%, 7.47%, 3.74%, 2.52%, 0.06% and 0.16%. The order of the load of the foreign materials were seen to be in the order of Plastics/Rubbers > Sanitary pads >Textiles/Fabrics > Others > Condoms > Gravels > Glass > Metals. These wastes pose mechanical and technical challenges to the treatment plant. Inasmuch as responsible environmental behavior through public sensitization on proper use of pit latrines in particular and the need for their redesign to make them almost impossible for use as dumping pits for other wastes were recommended, the utilization of some of these foreign materials that have the potential to be reused like the money, memory chips or mobile phones could potentially be a source of spread for disease like cholera and diarrhea as the FS contains a lot of pathogenic bacteria.

A Comprehensive Study on the Physicochemical Characteristics of Faecal Sludge in Greater Accra Region and Analysis of Its Potential Use as Feedstock for Green Energy

“…This is evidenced by the work of Doku [17] which indicates that high volumes of faecal sludge collected by vacuum tankers from cities and towns in Ghana were disposed on land and water bodies. The utilization of waste stabilization ponds, maturation ponds, facultative ponds, and anaerobic ponds had been the most used treatment technologies in Ghana over the years [10,18]. Most of these facilities had been reported to be in a deplorable state or not working effectively [14,19,20] and be used as dumping sites for nonfaecal matter [10,21,22].…”

“…The utilization of waste stabilization ponds, maturation ponds, facultative ponds, and anaerobic ponds had been the most used treatment technologies in Ghana over the years [10,18]. Most of these facilities had been reported to be in a deplorable state or not working effectively [14,19,20] and be used as dumping sites for nonfaecal matter [10,21,22]. The large volumes of FM being disposed into the sea has caused stench in some of the areas around James Town, Korle Gonno, and the environs in the Greater Accra Region of Ghana.…”

“…The characterization of faecal sludge based on public and private toilets differs widely by locality, from household to household, city to city, and district to district, but their characterization based on history only gives qualitative information [1,8,23]. The characteristics of collected faecal sludge vary greatly and depend on a number of factors [1,10,14,23,24]. What are these factors?…”

“…Research presented so far has reported on varying data characteristics of faecal sludge, making it very difficult for design usage purposes [1, 3, 6-10, 14, 23, 24, 26, 27]. This may have resulted in the collapse of most of the treatment facilities in the cities of Ghana [10,21,28] as engineers do not have access to comprehensive study of the physicochemical characteristics of the FS and its dynamics after application of some primary treatment such as dewatering. This information is not available in any of the current literature works [1, 3, 6-14, 24, 26-31].…”

“…Faecal sludge (FS) generated in Ghana and many developing countries is mainly made up of public toilet sludge (PTS) and septage [8] which are disposed of untreated and indiscriminately into lanes, drainage ditches, and open urban spaces [3,4,6,[9][10][11][12]. There are very few faecal sludge treatment facilities available to treat the many tons of sludge generated [9,10,13] specifically in Accra, thus making treatment of FS very abysmal. The process involved in FSM in Ghana within the context of FSM chain is fourfold: collection, transportation, disposal, and treatment.…”