Treatment of Petrochemical Industry Wastewater : A review

 Tr  Treatment of  Petrochemical Industry Wastewater astewater : A review  Treatm  Treatment ent of Petrochem Petrochemical ical Industry Industry Wastewater Wastewater including Membrane Technology

Rimeli Roy Choudhury (14/ChE/2015) /5/2015

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Treatment of Petrochemical Industry aste!ater " # re$ie! Abstract Abstract:: The wastewater from a petrochemical complex consists of numerous types of 

 pollutants including hydrocarbons, in free and emulsified form, phenols including cresols and xylons, mercaptans, sulphides, ammonia and cyanide. In this review paper, various industrial wastewater treatment technologies which are currently available are discussed. An extensive list of various methods of removal of mercury, chromium, cadmium, sulphur, nitrogen and other heavy metals and COD from petrochemical industry wastewater has been discussed.

Introduction:

etrochemical Industry is one of the fastest growing core sectors of the economy. As a result, many petrochemical plants of different si!es and technologies co"exist at the present time. The petrochemical industry is highly technological and capital"intensive. Tech Technologies nologies for petrochemical industries have been developing very fast. Tremendous resources and effo effort rtss are are bein being g cont contin inuo uous usly ly spent spent on incr increas easin ing g si!e si!e and and yield yield of plan plants ts thro throug ugh h continuous upgrade of catalyst, reducing energy consumption and cost reduction through novel process rate, new chemistries or scale up approaches. The petrochemical industry is a complex and is an integrated industry that includes a large variety of processes and products. #ecause of a large number of processes, use of wide variety of raw materials, catalysts, additiv additives, es, chemical chemicals, s, presen presence ce of explos explosives ives and ha!ard ha!ardous ous materia materials, ls, the proble problem m of  environmental pollution from petrochemical industries is also $uite complex. A wide wide varie variety ty of poll polluta utant ntss is disc discha harg rged ed into into wate waterr strea stream m and and emitt emitted ed into into the the environment. The $uantity and characteristics of wastewater generated from a petrochemical comple complex x is strongl strongly y depend dependent ent on indivi individua duall process process plants plants operati operating ng at the comple complex. x. %astewater generated from ethylene crac&er are inorganic sulphides, mercaptans, soluble

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Treatment of Petrochemical Industry aste!ater " # re$ie!

hydrocarbons, polymerised product, phenolic compounds, sulphide, cyanide, heavy oils, co&e, spent caustic, 'Ox, (Ox, hydrocarbons, particulates, water borne waste containing #OD, COD, suspended solid, oil and those from aromatic plants are dissolved organics, volatile organic compounds, heavy metals, hydrocarbons, particulates, ) *', 'Ox, (Ox, CO, water borne waste containing #OD, COD, suspended solid, oil + grease, toluene, ben!ene, xylenes, )Cl, chlorine, cadmium. These pollutants can lead to several direct effects on social and environmental health and almost appears in three dimensions of water, soil and vibrations. The most considerable is water and soil pollution which had the most effect on local ecosystems. As there are several pollutants present in the wastewater effluent from the  petrochemical industry so several techni$ues have been developed to omit or reduce the contamination of these pollutants. Treatment of petrochemical waste water to minimi!e its environmental impact has caught the devotion of researchers over the last few decades towards the development of an environment"friendly cost effective continuous method. Amidst the growing stringent discharge rules all over the world, petrochemical industrial houses has to suffer due to the formation of verities of wastes formed inside the industry. oreover, the treatment methods prior to discharge should be cheaper because the recovery and discharge processes by separation and purification technology plays a ma-or role in hi&ing up the cost of a complete process. )ence, our aim is to find a sustainable green and clean technology under reduced conditions of energy, material and energy and cost consumption with a promise to achieve higher engineering flexibility to the plant and lowest environmental impacts. Thus old, inefficient, energy intensive technologies should be replaced with new, smaller, safer and modular designed e$uipment. arge amounts of nitrogen and sulphur presents in wastewater effluent coming from catalytic hydro"crac&ing unit of petrochemical industries, in the form of ammonia /() 01 and hydrogen sulphide /) *'1, respectively. )ydrogen sulphide, one of the main constituents of 

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Treatment of Petrochemical Industry aste!ater " # re$ie!

 petrochemical industry effluents is a toxic and corrosive gas that causes environmental and economic problems in a variety of sectors. 'ome researcher has proved that one of the best way to control and remove sulphide is the use of nitrate 23,*,04. resence of ammonia and its derivatives in water effluent from petrochemical industry are one of those reasons which are responsible for water pollution. 5arious researches have been done for biological settlement of wastewater contaminated by ammonia and its derivatives. There are a number of aerobic and anaerobic microorganisms are there which are able to express the en!yme urease /urea amidohydrolase1 which catalyses the hydrolysis of urea 26,74. Copper and chromium are another two most common metals found in wastewater discharge of petrochemical plants wastewater discharge from other industrial sites 284 where hexavalent chromium, Cr/5I1  present at concentrations ranging from tenths to hundreds of mg9 2:4. irbagheri et al.2;4 used ferrous sulfate and lime Ca/O)1*  for p) ad-ustment and conversion of Cr/5I1 to Cr/III1 and Cr/III1 precipitation, respectively. is an activated sludge process periodically operated, fill"and"draw reactor 26;4 which has five discrete

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Treatment of Petrochemical Industry aste!ater " # re$ie!

 periods in each operation cycle fill, react, settle, draw, and idle 2664. >eactions start during fill with the reactor nearly empty except for a layer of acclimated sludge on the bottom and the reactor is then filled up with the wastewater and the aeration and agitation are started and complete during react. After react, the mixed li$uor suspended solids /''1 are allowed to separate by sedimentation during settle in a defined time period the treated effluent is withdrawn during draw and the time period between the end of the draw and the  beginning of the new fill is &nown as idle 26esearchers have been wor&ing on it and a number of papers also have been published which provide good description and evaluation of the '#> systems in treatment of heavy metals 266,7=F7*4. ala&ahmad et al 2704 treated synthetic refinery wastewater containing )g *L and Cd*L, in a '#> after acclimated the system for 8= days. The '#> was first introduced to mercury and cadmium in low concentrations which then was increased gradually to was able to remove :8Fichardson 36/01, *3es. 07 /*==31 8ubin, %ater nviron. >es., 8= /3esponse 'urface ethodology. Colloids and 'urfaces A hysicochemical and ngineering Aspects, 5ol. 0=*, (o. 3"0, *==:,  pp. *=6"*3=. 2*:4 )ossam Altaher, mad l]ada, %aid Omar. retreatment of %astewater 'treams from etroleum9etrochemical Industries ?sing Coagulation. Advances in Chemical ngineering and 'cience, *=33, 3, *67"*73

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Treatment of Petrochemical Industry aste!ater " # re$ie!

2*;4 %eit&, U., *===. Jeolite and catalysis. 'olid 'tate Ionics 303, 3:7e3;;. 2*.. Irvine, A.%. #usch, 'e$uencing batch reactors an overview, U. %ater ollut. Control Bed. /31 system, #ioresour. Technol. emoval of b*L and (i*L by bio"sludge in se$uencing batch reactor /'#>1 and granular activated carbon"'#> /GAC'#>1 systems, #ioresour. Technol. emoval of carbon, nitrogen and phosphorus from the separated li$uid phase of hog manure  by the multi"!one #ioCA'T technology. U. )a!ard. ater. *76"*77,086"0:3. 2774 'ambusiti, C., onlau, B., Bicara, ., CarrKere, )., alpei, B., *=30. A comparison of  different pre"treatments to increase methane production from two agricultural substrates. Appl. nergy 3=6, 8*":=. 2784 Qang, '., iu, J., *=36. ilot"scale biodegradation of swine manure via Chrysomya megacephala /Babricius1 for biodiesel production. Appl. nergy 330, 0;7"0emoval of COD and colour from livestoc& wastewater by the Benton method, U. )a!ard. ater. 370 /*==;1 3036F303