Waste-to-Energy Pathways

Waste-to-energy is the use of modern combustion and biological technologies to recover energy from urban wastes. The conversion of waste material to energy can proceed along three major pathways – thermochemical, biochemical and physicochemical. Thermochemical conversion, characterized by higher temperature and conversion rates, is best suited for lower moisture feedstock and is generally less selective for products. On the other hand, biochemical technologies are more suitable for wet wastes which are rich in organic matter. Thermochemical Conversion The three principal methods of thermochemical conversion are combustion (in excess air), gasification (in reduced air), and pyrolysis (in absence of air). The most … Continue reading

Use of Sewage Sludge in Cement Industry

The MENA region produces huge quantity of municipal wastewater which represents a serious problem due to its high treatment costs and risk to environment, human health and marine life. The per capita wastewater generation rate in the region is estimated at 80-200 litres per day. Sewage generation across the region is rising by an astonishing rate of 25 percent every year. Municipal wastewater treatment plants in MENA produce large amounts of sludge whose disposal is a cause of major concern. For example, Kuwait has 6 wastewater treatment plants, with combined capacity of treating 12,000m³ of municipal wastewater per day, which produce around … Continue reading

Deleterious Impact of Tire-Burning Kilns

Decorative arts such as woodworking, weaving as well as ceramics and other pottery have a long and honored tradition.  In fact, some of the earliest examples of pottery originate from the Middle East from the time of 6500 BC. In order to meet the ceramic industry’s high energy demand, much of the developing world, MENA in particular, is resorting to cheaper alternatives such as fueling kilns by burning tires and other harmful materials. Though modern technology has led to clean and efficient kiln usage in the developed world, these options come with a high price tag when referring to industrial … Continue reading

Energy from Wastes via Thermal Route

Thermal (or thermochemical) conversion systems consist of primary conversion technologies which convert the waste into heat or gaseous and liquid products, together with secondary conversion technologies which convert these products into the more useful forms of energy being heat and electricity. A wide range of technologies exists to convert the energy stored in wastes to more useful forms of energy. These technologies can be classified according to the principal energy carrier produced in the conversion process. Carriers are in the form of heat, gas, liquid and/or solid products, depending on the extent to which oxygen is admitted to the conversion process … Continue reading