Solid Wastes in the Middle East

The high rate of population growth, urbanization and economic expansion in the Middle East is not only accelerating consumption rates but also increasing the generation rate of all  sorts of waste. The gross urban waste generation quantity from Middle East countries is estimated at more than 150 million tons annually. Bahrain, Saudi Arabia, UAE, Qatar and Kuwait rank in the top-ten worldwide in terms of per capita solid waste generation. 

Saudi Arabia produces around 15 million tons of garbage each year. With an approximate population of about 28 million, the kingdom produces approximately 1.3 kilograms of waste per person every day.  According to a recent study conducted by Abu Dhabi Center for Waste Management, the amount of waste in UAE totaled 4.892 million tons, with a daily average of 6935 tons in the city of Abu Dhabi, 4118 tons in Al Ain and 2349 tons in the western region. Countries like Kuwait, Bahrain and Qatar have astonishingly high per capita waste generation rate, primarily because of high standard of living and lack of awareness about sustainable waste management practices.

In Middle East countries, huge quantity of sewage sludge is produced on daily basis which presents a serious problem due to its high treatment costs and risk to environment and human health. On an average, the rate of wastewater generation is 80-200 litres per person each day and sewage output is rising by 25 percent every year. According to estimates from the Drainage and Irrigation Department of Dubai Municipality, sewage generation in the Dubai increased from 50,000 m3 per day in 1981 to 400,000 m3 per day in 2006.

Waste-to-Energy Prospects

Municipal solid waste in the Middle East is mainly comprised of organics, paper, glass, plastics, metals, wood etc. Municipal solid waste can be converted into energy by conventional technologies (such as incineration, mass-burn and landfill gas capture) or by modern conversion systems (such as anaerobic digestion, gasification and pyrolysis).

At the landfill sites, the gas produced by the natural decomposition of MSW is collected from the stored material and scrubbed and cleaned before feeding into internal combustion engines or gas turbines to generate heat and power. In addition, the organic fraction of MSW can be anaerobically stabilized in a high-rate digester to obtain biogas for electricity or steam generation.

Anaerobic digestion is the most preferred option to extract energy from sewage, which leads to production of biogas and organic fertilizer. The sewage sludge that remains can be incinerated or gasified/pyrolyzed to produce more energy. In addition, sewage-to-energy processes also facilitate water recycling.

Thus, municipal solid waste can also be efficiently converted into energy and fuels by advanced thermal technologies. Infact, energy recovery from MSW is rapidly gaining worldwide recognition as the 4th R in sustainable waste management system – Reuse, Reduce, Recycle and Recover.

Biomethane Industry in Europe

Biomethane is a well-known and well-proven source of clean energy, and is witnessing increasing demand worldwide, especially in European countries. Between 2012 and 2016, more than 500 biomethane production plants were built across Europe which indicates a steep rise of 165 percent. The main reasons behind the growth of biomethane industry in Europe is increasing interest in industrial waste-derived biogas sector and public interest in biogas.  Another important reason has been the guaranteed access to gas grid for all biomethane suppliers.

Biomethane production in Europe has swiftly increased from 752 GWh in 2011 to 17,264 GWh in 2016 with Germany being the market leader with 195 biomethane production plants, followed by United Kingdom with 92 facilities. Biogas generation across Europe also witnessed a rapid growth of 59% during the year 2011 and 2016. In terms of plant capacities, the regional trend is to establish large-scale biomethane plants.

Sources of Biomethane in Europe

Landfill gas and AD plants (based on energy crops, agricultural residues, food waste, industrial waste and sewage sludge) are the major resources for biomethane production in Europe, with the predominant source being agricultural crops (such as maize) and dedicated energy crops (like miscanthus). In countries, like Germany, Austria and Denmark, energy crops, agricultural by-products, sewage sludge and animal manure are the major feedstock for biomethane production. On the other hand, France, UK, Spain and Italy rely more on landfill gas to generate biomethane.

A large number of biogas plants in Europe are located in agricultural areas having abundant availability of organic wastes, such as grass silage and green waste, which are cheaper than crops. Maize is the most cost-effective raw material for biomethane production. In many parts of Europe, the practice of co-digestion is practised whereby energy crops are used in combination with animal manure as a substrate. After agricultural biogas plants, sewage sludge is one of the most popular substrates for biomethane production in Europe.

Biomethane Utilization Trends in Europe

Biomethane has a wide range of applications in the clean energy sector. In Europe, the main uses of biomethane include the following:

  1. Production of heat and/or steam
  2. Power generation and combined heat and power production(CHP)
  3. Replacement for natural gas (gas grid injection)
  4. Replacement for compressed natural gas & diesel – (bio-CNG for use as transport fuel)
  5. Replacement for liquid natural gas – (bio-LNG for use as transport fuel)

Prior to practically all utilization options, the biogas has to be dried (usually through application of a cooling/condensation step). Furthermore, elements such as hydrogen sulphide and other harmful trace elements must be removed (usually trough application of an activated carbon filter) to prevent adverse effects on downstream processing equipment (such as compressors, piping, boilers and CHP systems).


Biomethane is getting popularity as a clean vehicle fuel in Europe. For example, Germany has more than 900 CNG filling stations, with a fleet of around 100,000 gas-powered vehicles including cars, buses and trucks. Around 170 CNG filling stations in Germany sell a blend mixture of natural gas and biomethane while about 125 filling stations sell 100% biomethane from AD plants.

Barriers to Overcome

The fact that energy crops can put extra pressure on land availability for cultivation of food crops has led many European countries to initiate measures to reduce or restrict biogas production from energy crops. As far as waste-derived biomethane is concerned, most of the EU nations are phasing out landfill-based waste management systems which may lead to rapid decline in landfill gas production thus putting the onus of biomethane production largely on anaerobic digestion of food waste, sewage sludge, industrial waste and agricultural residues.

The high costs of biogas upgradation and natural gas grid connection is a major hurdle in the development of biomethane sector in Eastern European nations. The injection of biomethane is also limited by location of suitable biomethane production facilities, which should ideally be located close to the natural gas grid.  Several European nations have introduced industry standards for injecting biogas into the natural gas grid but these standards differ considerably with each other.

Another important issue is the insufficient number of biomethane filling stations and biomethane-powered vehicles in Europe. A large section of the population is still not aware about the benefits of biomethane as a vehicle fuel. Strong political backing and infrastructural support will provide greater thrust to biomethane industry in Europe.