Wastewater Sludge as an Alternative Energy Resource: A Review

Abstract

<p align="justify">In recent years, concerns regarding to wastewater sludge disposal have increased globally. Production of sludge has increased recently due to the growth of population. Wastewater sludge classified as a hazardous substance, it is not easy to dispose because of certain treatment is required. Typically, sludge is treated at secured landfill which its limited in availability and expensive. On the other hand, wastewater sludge originated from biological treatment contains organic substance that can be converted into alternative energy resources. A technology is needed that is able to reduce the volume of sludge and convert sludge into energy source. We present an overview of various technologies that can be used for conversion of sludge into energy resources. Those technologies are anaerobic digestion, pelletization, combustion, pyrolysis and gasification. Progress and challenges of each technology is presented in detail. A summary of sludge characteristic originated from different source will be discussed as well. Emissions and residues that determines the environmental impact is also considered. Referring to some previous research, it known that wastewater sludge, as unwanted product, has the potential to become future energy resource. This potential can only be used properly if the method of conversion are effective and efficient.</p>

Evaluation of Community-based Sanitation Program Implementation in Central and East Java

“…Especially regarding the wastewater sludge which needs to be disposed properly. (Kurniawan, Hakiki & Sidjabat, 2018)…”

Wastewater sludge characteristics, treatment techniques and energy production

“…Using anaerobic digestion to provide energy from both types of wastewater sludge can obtain low-cost fuels compared with natural gas (Vatachi, 2019). (Kurniawan et al, 2018) According to Mills et al (2014), the United Kingdom water industry generates about 800 GWhpa of electrical energy from the sewage sludge. Traditionally energy recovery from sewage sludge features anaerobic digestion with biogas utilization in combined both heat and power systems.…”

“…Furthermore, the essential area for under drain sand bed area was 5,100 m 2 . content, it can be used as a potential energy source for future if it is properly used (Kurniawan et al, 2018). It is also observed that anaerobic digestion is preferable, for variety of sludge wastewater, but this method is limited in general (Vatachi, 2019).…”

Comparison of Global Warming Potential-Impact on the Handling of the Hazardous-Sludge From the Centralized Industrial-Wastewater Treatment Plant

“…While for the scenario in Figure 2, material transported to the landfill in a form of the fix-carbon residue from gasifier unit and liquid tar residue from gas-liquid separator unit. The amount of this residue less than the amount of dry (Kurniawan, Hakiki, and Sidjabat, 2018) In addition, green energy produced from the gasification process can also be used as an alternative energy source (McNamara et al, 2016;Ji et al, 2010). CO2 being an important constituent in our atmosphere, the changes of concentration in our atmosphere can affect the global climate (Sun et al, 2015;Anderson, Hawkins, and Jones, 2016;Kusrini et al, 2017;Zhang, Zhao, and Xu, 2017).…”

“…Figure 1 (a) The industrial wastewater; (b) Mechanical separation of solid particles from wastewater; (c) Dried sludge; (d) The existing flow of wastewater treatment and sludge handling (Kurniawan, Hakiki, and Sidjabat, 2018). …”