Loading...
Please wait, while we are loading the content...
Similar Documents
Opportunities for decentralised wastewater treatment and review of Skylytix TM technology for its potential as a sanitation solution for developing countries
| Content Provider | Semantic Scholar |
|---|---|
| Author | Cormick, Antony Mac Butler, Rhett |
| Copyright Year | 2009 |
| Abstract | Decentralised enhanced watersan solutions have been largely viewed as inappropriate, unworkable and relatively costly for developing countries. They have not been viewed as a viable option for low cost sustainable potable water supplies and/or sanitation solutions. Low cost, high quality sanitation outcomes are now urgent in the context of the MDG goals (1) . Recent advancements and innovations in “enabling” technologies” based on biominicy principles has lead to the migration of “new” treatment systems in the developing world. A new proposed treatment, Skylytix TM , is a combination of two recent innovative technologies. It is a decentralised concept that combines the world acclaimed Biolytix® wastewater treatment system with low cost UF membranes to produce a safe effluent. Perhaps with value engineering it could be adopted for developing world applications The emergence of “decentralised” solutions is challenging our established views of how to solve the global potable water and sanitation issue. The issues are complex and technology utilising low GHG consumption principles are worthy of critical evaluation, however, they are not a “magic bullet” solution. WHY DECENTRALISED SANITATION SOLUTIONS Developing countries are still lagging on MDG sanitation targets. Affordable sanitation solutions, as well as high quality potable water at a relatively low cost, will require a new “paradigm”. We should consider the merits of distributed and decentralised sanitation alternatives. This is a particularly urgent issue in the context of emerging cities and major peri urban population growth. It is time to embrace appropriate technology developments from developed countries. We should be not being quick to discard the obvious economies of “centralised wastewater solutions both from a cost and public hygiene perspective. However, significant capital cost and funding delays often mean that communities desperately need short term and immediate solutions. Decentralised and small scale systems are a mature technology. On site aerobic and anaerobic treatment is well understood in urban environments of developed countries. Clustered systems based on common effluent drainage principles are adopted for remote communities. The issues most often are not treatment quality outcomes but rather amortised cost per allotment and whole-of-life (WOL) operating costs. Translating the “cost” of these systems for application into developing countries is not easy. It is also essential to include maintenance inspection and regular accreditation or validation costs. This WOL cost must be fairly evaluated in the context of what is affordable for developing countries. Overall, there are challenges if we want to translate these proven solutions is a cost effective and responsible manner. Decentralised “cluster” or “Biowater” systems are best deployed in peri urban environments. The concept of a “Biowater” design essentially adopts a common effluent drainage design (CED). CED principles should be energy neutral if possible. The challenge for emerging cities will be the design dense multi story peri urban systems using locally available materials Figure 1: Concept design layout for an existing urban CED “Biowater” decentralised system WHY NEW “DELIVERY” APPROACHES ARE NEEDED IN CONTEXT OF MDG TARGETS This paper highlights the concept of a Skylytix TM sanitation system in the developing world context. There are many worthy sanitation and potable outcomes solutions that are candidates for community based (decentralised) sanitation solutions. That is, the combination of two Surplus collected in a low pressure small diameter poly pipe network Wetland and/or storage for beneficial reuse Example of Biowater ® “cluster” with onsite treatment Treat sewage on-site Collect highly treated & NOT raw sewage Reuse treated wastewater onsite for existing independent technologies to produce an integrated design. It is absolutely certain that a new “delivery” paradigm will be required to achieve the Millennium Development sanitation Goals and provide affordable sanitation to 2.6 billion existing people and meet additional targets by 2015 (2) . Sanitation systems that couple simple anaerobic treatment with say UF membranes add a new “value” dimension to what is historically a wastewater “issue” .We could also potentially harness a valuable resource in the byproducts. The proposition is that high quality, affordable decentralised water solutions that utilises new technologies, such as membrane technology and other innovations should be seriously considered by major health and humanitarian agencies. There is no simple formula to meet the MDG’s. Indications are that there will be a significant shortfall in the MDG target numbers of at least 600 million people (3) . (See Figure 2) It may well be feasible to engage these communities directly in the ownership and operations of essential infrastructure (at a modest level) until medium & longer term network solutions are feasible and affordable. In Africa less than 20 % of the population is connected to sewer, and in Asia it is marginally above 40% of the population (4) Decentralised or small systems for potable water solutions are not new. How do we accelerate their uptake in stressed communities? More importantly will this approach address the more pressing issues of sanitation, which far the more significant and costly issue. Concurrently, we also need to address the 4000 preventable deaths (5) every day. A critical assessment of the UNDP “benchmark sustainability criteria” warrant further independent evaluation of the technology based decentralised options. SANITATION SOLUTIONS ARE URGENTLY NEEDED FOR BASE OF THE PYRAMID (BOP) COMMUNITIES Four billion low-income people, a majority of the world’s population, constitute the “base of the economic pyramid”. New empirical measures (6) of their behaviour as consumers as well as aggregate purchasing power suggest significant opportunities for market-based solutions. These must not only address their basic needs for sanitation and water and but meet their aspirational requirements. It is only a matter of time before we see private sector “mechanisms” address this unmet demand. Figure 2: The proportion of households in major cities connected to piped water and sewers Source: WHO/UNICEF, 2000. Global Water Supply and Sanitation Assessment, 2000 Report. Geneva. Rapid urbanisation of developing countries (such as China, India and others) is increasing stress on networks. Most countries are not capable of funding or financing the huge public sector capital expenditures. Informal and unregulated network providers and vendors are meeting that demand. In most cases there are no regulations, standards are poor and water is potentially unsafe. In many cases they provide the only viable supply option. It is imperative that we seriously consider alternatives to these centralised networks. Decentralised sanitation is the only “logical” choice. New paradigms are required that remove the huge capital cost burden, inject flexibility in service and supply. Commonly where BOP communities lack access to municipal water supply networks, point-of-use water purification and small-scale community-based water purification and waste treatment can be useful solutions. Small-scale sanitation networks are the only option in peri-urban communities where serviced currently do not exist. We are evidencing improved point-of-use potable systems being devised and marketed by the private sector. Perhaps decentralised “partnered projects” will begin to show promise for better wastewater options especially in peri urban areas. New models of community engagement and publicprivate partnership are emerging. CENTRALISED VS DECENTRALISED SANITATION SOLUTIONS AN OVERVIEW There are many possible options to address the wider global issue. Clearly, the issue is much broader than simply treatment and technology options. However, a cost effective and robust set of technology options is essential. Traditional centralised networks and treatment philosophies have served us well. Capital cost is major structural issue for developing countries. Let’s examine the benefits of centralised sanitation solutions and why they have served us well; |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.skyjuice.org.au/wp-content/uploads/2017/03/IWA-DC-Final-Paper-Skylytix-Rhett-Butler.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
