alexa Production of Biodiesel from Wastewater Sludge Treatment by Direct Lipids Extraction

ISSN: 2090-4541

Journal of Fundamentals of Renewable Energy and Applications

  • Research Article   
  • J Fundam Renewable Energy Appl 8: 261, Vol 8(3)
  • DOI: 10.4172/2090-4541.1000261

Production of Biodiesel from Wastewater Sludge Treatment by Direct Lipids Extraction

Muhammad Usman*
Department of Chemical Engineering and Technology, University of Gujrat, Gujrat, Pakistan
*Corresponding Author: Muhammad Usman, Department of Chemical Engineering and Technology, University of Gujrat, Gujrat, Punjab 50700, Pakistan, Tel: +92 53 3643112, Email: [email protected]

Received Date: Apr 19, 2017 / Accepted Date: May 15, 2018 / Published Date: May 22, 2018


Biodiesel is outstanding amongst other elective fuel to the non-renewable energy sources which are non-renewable and will be run out in coming future. Because of an Earth-wide temperature boost and appeal of vitality we should move towards sustainable assets. Biodiesel production from wastewater sludge treatment by extracting the lipids are economically feasible because it has high contents of lipids feedstock with high yield of oil and negligible cost on feedstock. 49.4 ton for every hour biodiesel can be create from daily generation of wastewater of Lahore area in Pakistan. In this exploration we separate the triglycerides from the wastewater slime by coordinate technique through this we will ready to lessen the immense measure of city squander in to the helpful products which will secure our condition and a worldwide temperature alteration. Civil wastewater muck contains the assortment of natural mixes and inorganic mixes. Additionally, it predominantly contains proteins, lipids, sugar, and cleansers. The oil yield from wastewater muck treatment is exceptionally more prominent than alternate sources like soybean oil, microbiological, green growth and so forth as per the distinctive nations examine the lipids extraction from wastewater sludge treatment is aroeund 0.03$ for every gallon which is lower than different assets of feedstock for biodiesel.

Keywords: Biodiesel; Waste water; Sludge; Waste management


The vitality emergency makes because of the increments of industrialization and urbanization. They request the more vitality which is satisfied by the non-renewable energy sources which are nonrenewable and will be run out in the coming future. That is the reason we confront the emergency of vitality in everywhere throughout the world since high measure of fossils energizes is use in our necessity. We can control it through economic advancement by utilizing sustainable natural cordial vitality in our nation and even everywhere throughout the world. As indicated by the International Energy Agency, (Figure 1) the world will require 37% more vitality in 2040 than today [1].


Figure 1: Energy scenario.

There are numerous elective powers like biogas, bioethanol however biodiesel is a standout amongst the most essential elective fuel to the non-renewable energy sources. We can deliver it from sunflower, soybean, coconut, palm and jatropha (Table 1) which isn't temperate and now we should move to that materials which have exceptionally substance of oils like city wastewater slime [1,2]. City sewage slime has a high measure of lipids feedstock which is extremely valuable to deliver biodiesel [1,3-5]. What's more, the second alluring thing from metropolitan waste water slop is it delivers in vast sum and practical because our crude material is close going to free. In Pakistan it is the most essential issue how to defeat the wastewater which is delivered in expansive sum. With this thought we can regard the wastewater and their ooze which we regularly squander in our territories [6]. Through this perhaps we will ready to control the metropolitan waste and secure our condition. In Pakistan we have such huge numbers of assets to control the vitality utilization and in addition their generation as indicated by our requests. Municipal wastewater slime has numerous natural and inorganic segments which are recoverable [1,7]. Besides, it contains the household, mechanical, doctor's facility and agribusiness wastewater. We can remove the 99% lipids feedstock from wastewater muck however for this we require the more research work and great innovation [8]. On the off chance that I attempt to include the wastewater creation Pakistan or even a solitary city of Pakistan it has in huge sum like mega litres. Our enormous urban areas like Lahore, Karachi, Multan, etc. create high measure of wastewater as indicated by their populaces [3,6]. This strategy and crude material is one the least expensive which can satisfy our requests of vitality. Since this biofuel can be used in vitality division to run the creation plant. We can utilize it in our vehicle immediate or circuitous [5,7].

Biomass Oil content (dry basis) (%) Oil yield (dry basis) (g m-2 day-1)
Sewage sludge 18-20 1290
Microalgae 20-30 20
Palm 36 3.9
Rapeseed 42 0.65
Jatropa 28 0.67
Sunflower 40 0.47
Soybean 18-20 0.59

Table 1: All assumptions used for analysis.

Biodiesel is a standout amongst the most vital and promising fills in the elective powers to decrease the utilization of the fossils energizes. In everywhere throughout the world individuals are attempting to change over their activities from fossils powers to elective powers like biogas, biodiesel and so on. Presently a day's biodiesel is the most vital fuel which creates from creature fats, vegetables and our squanders [7]. In Pakistan, which is the created nation and face the numerous issue to deliver the vitality as indicated by utilization. It is profoundly required in Pakistan to create biodiesel from waste and utilize it in vitality areas [3]. A few nations are attempting to enhance this creation yet they all are utilizing the dry technique which is extremely sparing. Yet, we can create it through other technique which is immediate lipids extraction from wastewater slime this strategy is a savvy [8].

Materials and Methods

There is huge measure of wastewater create in even a solitary city because of the industrialization and overpopulation. Since it is the basic require for everybody in our industry and our residential purposes. As indicated by the examination slop substance in wastewater is close going to 140-160 mg/l. In Pakistan the waste water creation as per the 2005 report (Table 2). In Pakistan their wastewater generation sum every year by urban communities [3].

City Wastewater production106 m3 /y
Lahore 287
Faisalabad 129
Gujranwala 71
Rawalpindi 40
Sheikhupura 15
Multan 66
Sialkot 19
Karachi 604

Table 2: Wastewater production from different cities of Pakistan.

The extraction of lipids from wastewater muck is the most imperative factor in our everything thought [9,10]. The primary strategy which is utilized as a part of our examination that was the dry technique [2,5,11] which comprise of following advances:

• Sewage sludge: Is a semi strong material which is build up in the wastewater treatment.

Filtration: Partition method is utilized to isolate the other waste in slime like paper, wood and so on.

• Drying: Process used to think and setting the discharge.

• Strong fluid extraction: This additionally a partition strategy which is utilized to isolate the fundamental product lipids from strong with the assistance of dissolvable like Hexane.

• Transesterification: Is a response of triglycerides with liquor which creates biodiesel and glycerol.

• Separation: With the assistance of refining segment we isolate the biodiesel from glycerol in view of breaking point or greater instability.

• Products: Last after effects of process which is biodiesel.

There are diverse kinds of metropolitan wastewater slime (essential, auxiliary, settled). In essential civil wastewater slime has the high substance of lipids instead of other. The lipids are separated by utilizing hexane in an extractor and change it into the biodiesel by transesterification. Yet, for this we needed to change the semi strong muck into the dry ooze which is generally costly [2,4,11,12].

Straightforward stream graph of dry strategy is shown in Figure 2. In which you can see that we should dry and hardening the slop which costlier and it is a major test to conquer these issues [3,13].


Figure 2: Dry method for biodiesel production.

In any case, now we have another strategy to expel the lipids in prudent courses by coordinate lipids extraction by utilizing hexane dissolvable in a blender pioneer and can change over it in our required products biodiesel. In this technique we won't have to apply the drying of slop and we can spare the vitality which make it temperate and financially savvy [4,11-13].

• Sewage sludge: Semi strong material which is delivers when we treat the wastewater.

• Coordinate lipid extraction: In this strategy we will remove the lipids from wastewater slop without dry the slime.

• Transesterification: The response of triglycerides with the liquor in which lipids change into biodiesel and glycerol.

• Detachment: To isolate the primary product biodiesel from glycerol in refining section.

• Products: Biodiesel and glycerol.

The procedure is shown in Figure 3 demonstrating the wastewater treatment and slime treatment by coordinate lipids extraction in this technique we needn't bother with the drying of slop.


Figure 3: The process flow diagram of biodiesel production by direct method which is made on MS VISIO.

After the accumulation of wastewater and oxygen consuming treatment of wastewater we got the wastewater slop from where we separate the lipids content with the assistance of hexane and lipids than respond with methanol within the sight of sulphuric acid which is utilized as an impetus. After the response of reactant, we isolate the items which are glycerol and biodiesel with the assistance of thickness contrast. Glycerol is a side-effect which is utilized as a part of essentially nourishment industry for sweating the sustenance [4,5,9,14].

Process available for transesterification

There are three procedures accessible which are given underneath:

• Enzymes-catalyzed

• Base-catalyzed

• Acid-catalyzed

All procedures are same yet the component which may shift that is mechanism, product quality, cost, site product generation. In this research we are using acid-catalyzed transesterification because of some advantages on other process like, catalyst recovery, no soap formation, fast reaction etc.

Reaction and calculations

Triglycerides +3 methanol → 3 biodiesel + glycerol

(885.46 g) (96.12 g) (889.5 g) (92.10 g)

In this reaction we obtain the two products biodiesel which is named as fatty acids methyl esters (FAMEs) and the glycerol. If we just discuss about the single city Lahore of Pakistan. In Table 3 it has the very amount of waste water in the Mega litre per year.

Components Total sludge %
Hemicellulose 1.5
Cellulose 19.3
Lignin 8.2
Ash 22
Water 0.8
Amino Acids 13.2
Grease (Tryglycerides+Fatty acid) 35
Total 100

Table 3: The composition of wastewater sludge.

1 ml=140-160 kg sludge

1 ml=140-160 kg sludge

117945×(0.28) = 37 kg triglycerides/day

In wastewater sludge the composition consists of 35% Grease (triglycerides 28%, Free fatty acid 7%)


117945×(0.28) = 37 kg triglycerides/day

If we take assumption 99% conversion of triglycerides in biodiesel then, 30m3 / day=8981 gallon/day or 49.5 ton per hour biodiesel production is possible.

Results, Discussion And Conclusion

Biodiesel creation from wastewater muck treatment by coordinate lipids extraction would be the immense chance to deliver the elective energizes to the traditional powers (Table 4). The following are results of components in wastewater sludge [9,12,14].

Sludge type Experiment type TS (%) VS (%) Lipida (%)
Primaryb Sludge drying 3.9 ± 0.1 2.9 ± 0.1 26.3 ± 0.5
Primaryc Liquid-liquid extraction 3.4 ± 0.1 2.7 ± 0.1 25.2 ± 0.2
Secondaryc Liquid-liquid extraction 3.8 ± 0.1 3.2 ± 0.1 7.7 ± 0.1
Blendedc Liquid-liquid extraction 3.5 ± 0.1 2.7 ± 0.1 21.1 ± 0.2
a - Extraction according to standard MgSO4.H2O method, lipid yield on the basis of dry sludge
b - Lipid extracted from non-acidified sludge
c - Lipid extracted from acidified sludge
Values are mean ± SD, n=3

Table 4: Characteristic of wastewater sludge in different experiment work.

By dry technique and direct lipids strategy it demonstrates the insignificant variety in a basic decimal. In the wastewater slop has the high substance of glycerides and unsaturated fats. It would be the advantageous to deliver the biodiesel [11]. Relatively same measure of biodiesel produces from the two techniques; however, sparing is the one which is immediate lipids extraction. On the off chance that we analyse between coordinate technique and dry strategy (Table 5) there is minor contrast in level of yield i.e., 19.8% by coordinate strategy and 21.2% by dry strategy [4].

Lipids Lipids Yield (%)
Direct method Dry method
19.8 21.2

Table 5: Lipids yields by direct and dry methods.

With the help of this method and the raw material viability in the high amount we can produce a very large amount of biodiesel from a single city of Pakistan is near about to 8500 gallons per day or 49.5 ton per hour which is a very huge amount of biodiesel and can be used in the energy sector to produce electricity. Through this we will be able to control the wastewater treatment their waste which will help us to protect our people as well our environment [15].

Direct liquid-liquid extraction of lipids from wastewater sludge for the biodiesel production with the hexane solvent on different time several results are shown in Figure 4.


Figure 4: Effect of EXTRACTION time on the lipids yields with different sludge to hexane volume ratio.

From the above results highest percentage of lipids yields obtained at the 60 min, 28.15%, 28.79%, and 29.1% respectively. Overall If we want to improve it up to greater than 90% we will need the three consecutive extraction stages at the 60 min with the sludge to hexane ration 2:1, 1:2,1:1.

The production of biodiesel from wastewater sludge treatment will be cost effective if it would be run on continuous operation. Therefore, we will need the batch process for scaling up this production.


Citation: Usman M (2018) Production of Biodiesel from Wastewater Sludge Treatment by Direct Lipids Extraction. J Fundam Renewable Energy Appl 8: 261. Doi: 10.4172/2090-4541.1000261

Copyright: © 2018 Usman M. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Select your language of interest to view the total content in your interested language

Post Your Comment Citation
Share This Article
Recommended Conferences
Article Usage
  • Total views: 475
  • [From(publication date): 0-2018 - Jul 23, 2018]
  • Breakdown by view type
  • HTML page views: 436
  • PDF downloads: 39

Post your comment

captcha   Reload  Can't read the image? click here to refresh
Leave Your Message 24x7