Proceedings Venice 2006, Biomass and Waste to Energy Symposium Venice, Italy, 29 November 1 December 2006 2006 by CISA, Environmental Sanitary Engineering Centre, Italy

A MODEL OF SUSTAINABLE DEVELOPMENT IN AREAS WITH LIMITED RESOURCES

S. ALTERIO**, F.C. CAMPIONE*, A. MILONE** AND D.MILONE**

* Facolt di Architettura,Universit di Palermo, Viale delle Scienze, Edificio n14- 90128 Palermo,Italy ** DREAM,Dipartimento di Ricerche Energetiche ed Ambientali, Universit di Palermo, Viale delle Scienze, Edificio n9- 90128 Palermo, Italy

SUMMARY: Tourism is one of the most important economic sector for a island , but put relevant pressure on the natural resources and cause problem linked to management of solid waste, water resources, waste water and energy saving, therefore the islands needs an overall strategy looking at the entire water cycle, solid waste management and energy saving integrating the environmental, social and economic parameters. The pressure on resources is higher during summer period due to increased water from the tourism sector with production of solid waste, wastewater and energy consumption and affect problems linked to management of solid waste, wastewater and residential consumption very high. Better performance can be obtained by improving a sustainable development to save water, energy and resources. Therefore further planning policy need to be considered, also taking into account the integration between tourism and environmental strategies.

A sustainable management pratice of water resources, must not only take in to account, but also respect the balance between the components of the water cycle (rainwater, terrestrial water: lake, rivers, marine water, wetlands) all must be managed in a holistic manner that is based on their particularities and implications, using all the available tools and methods for water, energy saving and reducing waste.

The present study intend to go in to the question of desalination plants applications in small islands where to congenital lack of fresh water, it adds a great demand of water because of the tourist flow in the summer period. The autors after aving passed in review the desalination plant applications in small islands of Sicily, propose a seawater desalination plant (MSF) in the archipelago of Eolie islands with recovery of energy from (WTE) waste-to-energy plant and biomass where the benefit obtained water and energy may result in the recovery of financial resources invested.

Water cycle is the integrated water source model of nature.

1. INTRODUCTION

The purpose of the research has been a cognitive investigation developed in the archipelago of Eolie Islands, localized in the limits of the territory north-east of the Sicily, with the aim of know te present state of health of residential water and Municipal Solid Waste management systems, to make feasible a model of sustainable development advanced.

The research it was developed in two stages: - Stage one: a cognitive investigation and analysis of the informations examined on-site; - Stage two: a feasibilitys study for a desalination plant with power supplied from Municipal Solid Waste (MSW) and Biomass;

With the first stage of the research , it was possible to know at present the water resources supply, pollutant load from urban waste water discharge , waters consumption from domestic use , the amount of MSW (Municipal Solid Waste) , land use , and examine these data sources.

2. COGNITIVE INVESTIGATION FOR GEOGRAPHICAL AREA

The geographical area object of the investigation includes n.7 islands (the archipelago of the Eolies figure 1). The surface amount of the islands is about of 121,60 Km2., with a ratio of 98 inhabitants/Km2. and 12.020 resident inhabitants.

Here in Table 1 are reported for different islands, surfaces and population trend (Resident inhabitants and Tourist flow).

Table 1. - Surface, resident inhabitants and tourist flow

The values related to the surface, population trend and tourist flow, increases during summer season, reaching a maximum tourist flow of 580.814.

Most of the islands in summer season (from June to September), must faceup to amassive tourist flow that involve a considerable increase of inhabitants and consequently of waters consumption for domestic use, production of M.S.W. (Municipal Solid Waste) , urban wastewater and very high consuptions of electric power ,because of large use of heat-pump air condiction systems .

This problem produce a decompesation for the local communities in organizing and management of water supplies and municipal solid waste, and the often the local infrastructures are insufficient to solve these problems that increase in summer, due to tourism flow .

These problems are continuing to grow and new solutions ,therefore must have developed in order to maintain the quality of life, desired by the community.

Local economies, developed on the islands , are founded on the tourism industry, agriculture

(sector wine's production) and the public sectors (Hotels, restaurants, offices). The management of collection Municipal Solid Waste is carried out by each inter municipal

company, with a series of environmental problems, that arise from the amount of Municap Solid Waste in summer season and the municipal companies of the islands are available for a global management of MSW, for reduce this problem.

At the present , as regards to MSW , urban waste water and power supply management , today there are burdens that produce problems and the municipal companies must find an answer these problems.

An integrated system during the collection, the transportation and in the treatment of MSW , could produce a saving in management overheads, and increase the quality adaptable to sustainability criteria.

For the sustainable tourism of the archipelago, must be considered the development of services and infrastructures that are necessary to comfort, services that are insufficient for the resident inhabitants during the winter season.

Every summer therefore, come back the problem caused by the environmental impact of the touristic flow , producing a discomfort for the inhabitants and the tourists. Because of insufficient infrastructures, the archipelago loses a considerable part of charm and export an image of disorganization that is accompanied so to the landscape of the islands .

The climate of the archipelago of Eolie islands, because of the brief rain, it is notably dry (about 19,68 in. to 23,72 in. of rain during the year ); the rain that falls on the ground, is about 50 to 100 days of rain, with a maximum value during the winter season.

Figure 1. Archipelago of the Eolie Islands

2.1. Receptiveness touristic of Eolie islands

Lipari Island : it is still the island that has the most greater percentage of touristic presences (402.139);Vulcano Island : 62.820 presences, Panarea: 24.049 presences, Stromboli: 45.722 presences, Salina island : 42.000 presences, Alicudi and Filicudi Islands : 4.084 presences.

2.2 The water supply in the archipelago of the Eolies Islands

The absence of sources on the whole archipelago, has characterized the human life on the islands since its origins, forcing the man to contrive collection systems of rain water in storage tanks. Typical the roof of the house, in style Eoliano, used for carrying the water in storage tanks. At present the islands are supplied by tanker coming from Napoli, Augusta and during the summer also from La Spezia.

The water that arrives on the archipelago is distributed through the water system or through the service of tank trucks (above all for the most distant centers on Lipari and Vulcano), it has a tall social cost and therefore it is necessary a sustainable management net to avoid every possible waste.

The desalination plant of the Lipari Islands, supplyes around 2.800 m3/days in winter and 4.045 m3/day in the summer, with a total of 989.943 m3/year. This quantity, doesn't resolve the problem water supply of the islands, in how much the smaller islands continue to have served from tanker however, with a cost that today it wanders around 22 million euro/year. On the islands Eolie the cost of the water is around of 0,62 euro/litre , and the population because of this, considers the water a resource precious for use in the optics of sustainability.

During the summer the use of the water resources have a increase , due to the impact that the tourism has on the Eolie Islands territory.

From the moment that the islands Eolie don't have water resources to satisfy the demand of water supply, from many years the islands have a service of water supply, and this service is managed from " Ministry of the Defence " this because, once, the water supply was performed from military ships. 2.3 To make these islands self-sufficient

The island of Lipari has a desalination plant that, to full regime, it produces around 4.045 m3/day of water , but this quantity is not enough in the summer season for the demand of the water supply for the islands . The water requirement in winter it is so esteemed:

12.020 Inhabitants. x 0,3 m3./ Inhabitants x day x 30 days = 108.180 m3/ month

The summer water requirement is so esteemed:

158.971 Tourist Flow x 0,08 m3. / Tourist x day x 30 day = 381.530 m3/ month

12.020 Inhabitants x 0,3 m3./ Inhabitant x day x 30 days = 108.180 m3/ month

The amount of the required monthly water supply in the summer season is of 489.710 m3./month.

The amount of the provisioning of water is used for domestic use and for tourist flow. Domestic use , includes : water for normal houseold pourposes, such as drinking , food

preparation bathing, wasing clothes and dishes, flushing toiletes and watering lawns and gardens.

According to water's consumptions effected for the Eolie islands , the amount of water supply, is evaluated about 1.000.000 m3 .

Here following in Table 2 are reported the values for water supply amount ( m3/month ), to distribute in the Eolie Islands.

Table 2. Water supply in the archipelago of the Eolie islands (m3)

In Figure 2 are reported the values related to the production of water for the desalination water system of Lipari island.

Figure 2 Water supplied from the desalination water system (Lipari Island)

At present , for to face the water supply, because of the tourism flow , considerable quantities of water are purchased by outside companies ( about 59%) , with costs of around 16 euro/m3 , while the 41% of the water is produced by the desalination water system, situated in a named place Canneto ( in the Lipari island , see figure 6 ) .

The desalination water system , is assembled on three stages evaporative , with unitary capacity of 63,36 m3/h, the evaporation system is of the type vacuum - packed, couple with a vapor compression system (MWC) Multiple Vapor Effect, to low temperature of exercise and consist of four multi stage-evaporation.

3. DESALINATION WATER SYSTEM AND WASTE- TO- ENERGY PLANT

In order to face the problems that arise from water supply and to reduce the amount of costs of water purchased by outside companies (about 22 millions euro/year), in the present study is considered the energy potenzial from MSW (Municipal Solid Waste) for providing the energy demand of desalination water system.

It is considered the refuse derived fuel (RDF) as energy resource for desalination water system in a combined- cycle plant used with sea water desalination units.

The electric power out and the flow process steam is provided by RDF (lower heating value:14,65 MJ/Kg) from MSW and biomass.

Because of the tourist flow during the year, has been possible to evaluate the amount water supply demand : (about 1.998.557 m3/year).

In figure 3 is visualized the combined cycle plant used with desalination water system and waste to energy plant, while the figure 4 is visualized the Flow sheet energy potential from MSW to provide energy demand for desalination water system.

Tipical waste of the Eolie Islands consist of : Paper and paperboard 20-40 % by mass, garden and food wastes 20-35 %, wood 2-6 %, plasti 6-10 %, texile 2-6 %, glass 3-8 %, metals 3-10 % , and inert matter up to 10 %.

In according to composition of the MSW , that varies considerably and depends on many factors , such as localization , etc.

Figure 3. Block diagram: desalination plant and waste-to energy plant

In table 3, is visualized the amount of MSW production during the year (10.786,41 T/year), while the Figure 4 shows the trend of MSW production, during the year (kg/month ) in the island of Lipari.

According the composition of MSW , it's possible to evaluate a production of RDF around : 7.011 T/year,with a flow of 19,2 T/day.

Table 3. Municipal Solid Waste (MSW) amount (Kg./month): Eolie Islands

Figure 4. - Municipal Solid Waste amount (Kg./month) : Lipari Islands

On the base of evaluations of technical character and cognitive investigation , has been possible to evaluate the performance of the integrated system : - Flow of R.D.F. : 800 Kg/h; - Thermal ability of the section of combustion: 3,25 MWt; - Lower heating value : 14,65 MJ/Kg; - Power of steam turbine : 2,57 MW; - Power absorbed by the system: 0,064 MW; - Power to the plant: 5,76 MW; - Flow of vapor: 3.505 Kg/h; - Desalinated water (D.W.): 24 m3/h;

- Specific consumption of heat: 1,22 KWh/Kg; - Daily production of D.W. : 576 m3/day; - Produced mechanical energy: 391 KW; - Available electric energy: 371 KW;

Figure 5. Flow sheet of the desalination water system and waste- to- energy plant

Legend: 1 Gas turbine 6 - Feedwater tank 2 - Steam Turbine 7 - to Press reducing station 3 - Waste heat boiler 8 - Supplementary firing 4 - Desalination unit 9 - Fresh air fang 5 - Make up water tank HRSG- Heat recovery steam generator ST- Steam turbine With reference to the figure 5, we want to put in evidence that the our proposal, has the following objective: - to supply water for the Eolie islands, as principal function of environmental sustainability; - to maximize the specific production of water supply;

The performance of the integrated system, it is result determined by the availability of electric and thermal energy and taking in consideration the inside consumptions .

Particularly the performance of the unity MED, where the demand of thermal energy application, is preponderant in comparison to that electric, is defined by the availability of heat to low temperature associated to the entalpia of the discharge vapor of the turbine.

3.1 Optimization of the integrated system

We also considers the possible energy potential from biomass , for to satisfy the energy demand of the desalination water system for water supply of Eolie Islands.

This biomass is produced in the basin of use of the province of Messina ,and after to be transformed is carried with tankers from Milazzo to the Lipari Island

On the base of preceding evaluations, there are reported the values for converting the biomass from agricolture to energy and the heat is used directly in a integrated system, so the integrated system burns the biomass by itself. Typology of biomass ) Residuals of the grasses from : ( wheat, artichoke, fave and tomato ) Amount of biomass : 24.565 T/year; Embody energy : 3.721 t.e.p.; Typology of biomass B) Residuals of crops from (vite, olivo, citrus, almond tree and walnut tree , etc.); Amount of biomass : 156.632 T/year; Embody energy : 3.091 t.e.p.; Typology of biomass C) Woods by- products of agro-forest Amount of biomass : 13.198 T/year; Embody energy: 2.725 t.e.p.;

In the case of utilization of the amounting biomass (194.395 T/year) , available in the basin of use of the province of Messina , the total energy supplied by the biomass, it amounts about of 9.537 t.e.p and it's able to supply the water demand during the year.

Besides the energy provided by biomass, supplies to electric power and to the total heating demand of the desalination water system.

The use of biomass to save energy , it doesn't contribute to the effect it shuts, since the quantity of carbonic anhydride released during the decomposition because of the energetic conversion, is equivalent to that absorbed during the growth of the same biomass; therefore is no some clean contribution to the increase of the level of carbonic anhydride in the atmosphere. 3.2 Consideration on waste to energy plant ( Lipari island)

- The cost of the waste to energy plant, is esteemed in: Euro 52.000/T MSW x day; - The cost of the desalination water system, is esteemed in 60 million of Euro; while the electric energy consumption, is about 2,75 Kwh/m3 - The amount surface occupied by the two integrated systems is of around 1.600 m2.;

Figure 6 . Lipari Island: desalination plant at present and new desalination plant

CONCLUSION

In both developed and developing countries the concept of sustainable development, and its pratical implementation, is considered to be one of the most critical mechanism to help achieve a between economic and environmental objectives. Sustainable water resources management is essential for ecosystem protection. Energy, waste and water resources management must be integral components of a sustainable environment. The Eolie islands needs an overall management strategies looking ay the entire life cycle and integrating the environmental, social and economic parameters.

The shortage of endogenous energy recources, involve a massive care in the research and in the exploitation of energy recovery from Municipal Solid Waste and biomass.

A choice like this can help to reduce in meaningful way the problem of transport with tankers for water supply.

A sustainable management pratice of water resources, must not take into account but also respect the fragile bilance between the components of water cycle. Rainwater, terrestrial water (lake, rivers), marine water, wetlands: all must be managed in holistic manner.

REFERENCES

D.Almorza, C.A.Brebbia,D.Sales,V.Popov: Waste Management and the Environment, Ed.Wessex Institute of technology,UK, Ed.2004;

C.A.Brebbia: Water Resources Management, Ed 2004; F.D.Pineda, C.A.Brebbia, M. Mugica: Sustinable Tourism, Ed.2004; A.Milone, F.C.Campione: Riciclaggio termico di flussi di r.s.u.: II Convegno Nazionale,

Abano Terme (PD), 1999; F.C.Campione, G.Salemi: A metodology to localize a desalination plant: the case of Ustica,

Congresso Internazionale Desalination Technologies for small and medium size plants with limited environmental impact , Rome, 1998;

F.C.Campione, A.Milone : Potenziale energetico da biomasse nellindustria di trasformazione, I International Conferece on Solid Waste, Roma 7/9 aprile 1999;

F.C.Campione, A.Milone, D.Milone : Studio di fattibilit per il teleraffrescamento dai rifiuti urbani III Convegno Nazionale, Abano Terme (PD), 2001;

F.C.Campione, A.Milone : Propettive del recupero energetico e del riciclaggio dei rifiuti cartacei, XXIII Congresso internazionale Nuove tecnologie e il futuro dellindustria cartaria , ATI CELCA , 2002.