Treatment of Effluents of Hayatabad Industrial Estate Peshawar, KPK

(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016 Treatment of Effluents of Hayatabad Industrial Estate Peshawar, KPK Ars...
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(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016

Treatment of Effluents of Hayatabad Industrial Estate Peshawar, KPK Arshad Ullah Civil Engineering Department Iqra National University, Peshawar, Pakistan [email protected] of industrial areas have high amount of biological oxygen demand (BOD) and organic matters. The micro-organism will consume more oxygen from the water. If continuously this process occurs, then the death of fishes will occur due to deficiency of oxygen 0.

Abstract—Industrial development play a vital role in the economy of a country. It reduce the unemployment rate and also provide and develop the basic facilities to the human beings. Waste water has been generated by industries during the production process. In Pakistan these effluents has been discharged into the water bodies without treatment. The effluents of Hayatabad Industrial Estate (HIE), Peshawar, are disposed off into River Kabul without any treatment, which affect the aquatic life, ground water and environment badly. This study deals with the estimation and characterization of pollutions load discharged by the HIE and possible solutions to control these effluents at its source or at a Combined Effluent Treatment Plant (CETP). The study shows that toxic effluents cannot be treated at source due to high cost and non-availability of land at the sites already developed. Also it is not advisable to install individual treatment plants due to lack of technical knowledge and high maintenance costs. The solution for this is to install a CETP at a suitable location on common benefit and maintenance cost mechanism. Complete-Mix Activated Sludge Process (ASP) is selected for the treatment of HIE effluents. The recommended process will be able to treat and bring the effluents within National Environmental Quality (NEQ) limits before releasing them into open water bodies. This will greatly improve the irrigation water quality, aquatic life, human health and environment.

The unpleasant changes in the chemical, biological and chemical feature of environment is known as pollution such water, soil and air pollution. Pollution are mainly caused by industries. They have directly or indirectly affected the humans and biodiversity 0. The protection of surface water from pollution of waste water play an important role in the development 0. About 1.5 billion people have no access to safe water for drinking and almost 5 million people die from water borne diseases annually 0. In Pakistan, particular in Peshawar, the pollution of water is one of the significant threats to the community health. The quality of water use for drinking is poorly monitored. Due to improper release of effluents from industries and municipal buildings, Pakistan ranked at number 80 on the basis of drinking water quality among 122 nations 0. About 4432.35 million cubic meter of waste water is generated in industries in Pakistan 0. The Hayatabad Industrial Estate have no proper arrangement for waste water treatment. Therefore, there is a need of effluent treatment plant to improve the quality of water before their disposal into the River Kabul. The study will propose the suitable and economical process for the treatment of effluents of Hayatabad Industrial Estate. II.

The Hayatabad Industrial Estate (HIE) is situated in Peshawar, the capital of Khyber Pakhtunkhwa (KPK). It was established on above 868 acres area in 1964. This is the major industrial estate in KPK. Various types of industries and Small Industrial Development Board (SIDB) units have been set up in the HIE. The data of all functional and non-functional and the type of industries have been complied and analyzed and depicted below in self-explanatory bar charts.

Keywords—Waste water; Treatment; Complete-Mix Activated Sludge Process; Combined Effluent Treatment Plant.

I.

INTRODUCTION OF THE PROJECT AREA

INTRODUCTION

The human beings, animals and plants lives cannot possible without water, because 80% of water is approximately contained by most living cell protoplasm. Water has been involved in every activity of life. It has been used for the pollutants disposal. These water come back to the environment with high pollutants concentration. Industries are the main source of causing water pollution, because it consist of fatal metals and toxic gases 0.

The effluents from these industries are discharging with high biological oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS) concentration. The estimated flow rate of effluents is 813.6 m³/hr. A Combined Effluent Treatment Plant (CETP) for the HIE is recommended to treat these effluents before mixed with water bodies.

The precious resource on the earth is clean water. The protection of environment is not possible without clean water in the rivers, lakes and oceans. The waste water disposal into these water bodies are the major problem in the recent years. The effluents

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(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016

Fig. 1: SIDB Operational Units

Fig. 4: Closed Industries

III.

LITERATURE REVIEW

Water is a vital element of all living organisms. The existence of life is not possible without water. The surface water has been contaminated continuously due to mixing with industrial effluents in the recent years 0. The nature has been interfere by humans from ancient time. The demand of establishment of industries are increasing to overcome the need of humans due to rapid population increase. The amount of effluents and other pollutions are increasing due to industrialization. Proper methods should be adopted to treat the waste water before releasing into environment 0. The industrial development has resulted in production of waste water. Different types of pollution has been generated from these industries. The chronic poisoning are produce in aquatic animals due to presence of heavy metals in these effluents. The water become inappropriate for irrigation and drinking 0. Several diseases like diarrhea, skin rashes, typhoid and hepatitis are caused by using waste water. Animals, vegetation and soil are also affected adversely by the use of these water 0.

Fig. 2: SIDB Closed Units

The industrial effluents are commonly not treated in Pakistan before their discharge into the rivers. By drinking these toxic polluted water, deaths of animals have been taken place. Each industry have no suitable treatment arrangement. The quantity of TDS, TSS, COD and BOD are higher than National Environmental Quality Standards (NEQS) in the HIE waste water. Treatment plant should be established to treat the polluted water of the estate 0. The quality of water use for recreational purpose or for drinking has been effected to a great extent. A solution should be produced to this problem. The effluents of HIE was tested and the result shows that some parameters have a deviation from NEQS. Therefore, these untreated pollutants effects the life and must be treated before their disposal into the environment 0.

Fig. 3: Operational Industries

The effluents released from the HIE have endangered the ground water quality. The effluents have contaminated the sub surface water. The arrangements for the treatment of waste water are necessary at each industry 0.

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(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016

IV.

concentration of pollutants. The treatment may include any of the following operations.

DESIGN INFLUENT WASTEWATER CHARACTERISTICS

Daily pollution loads of BOD, COD and TSS was adopted by applying a factor of safety of 1.5 to those based on measured values, to account for the uncertainties of data and various assumptions made for the analysis. Since design concentrations to the measured concentrations was ascertained. Field measurement of wastewater pH value, temperature and conductivity was made. Wastewater samples were collected and got tested, at the laboratory of PCSIR for the pertinent quality parameters, as follows.

A. Equalization and Neutralization In equalization the wastewater has been hold in a continuously mixed basin for a pre-definite time to make a uniform water. While neutralization means neutralizing the excessive acidity or alkalinity of the particular wastewater, by adding alkali or acid, respectively to the wastewater. B. Physical Treatment The inorganic suspended matters are separated with physical treatment such as primary and secondary sedimentation. Skimming process is generally used for the removal of oil and grease from the wastewater.

TABLE 1 WASTEWATER CHARACTERISTICS OF HAYATABAD INDUSTRIAL ESTATE Waste wate r Characte ristics (At Sampling time ) pH

6.77

T emperature

25°C

C. Biological Treatment The aerated lagoons, trickling filters, oxidation pond system and activated sludge process are the most commonly adopted biological treatment processes.

Grab Waste -wate r Characte ristics (Laboratory) pH

7.5

Biochemical Oxygen Demand (BOD)

280 mg/L

Chemical Oxygen Demand (COD)

300 mg/L

T otal Suspended Solids (T SS)

450 mg/L

V.

VI.

RECOMMENDED SPECIFIC TREATMENT

The effluents released from industries are widely much more polluted than the commercial or even domestic waste water. Some of the industrialists are still trying to dispose their effluents into streams and natural rivers. These industrial wastewater may contaminate the entire river water to a great extent, hence its purification become almost impossible. Toxic matters and chemical pollutants up to a great extent contained by the wastewater release from industries. The characteristics and toxicity of the wastewater generated are usually different from one industry to another industry, even in the same industry it can vary in each process. The treatment of such industrial wastewater cannot be easy by treating it with normal domestic treatment methods. A special treatment method should be applied to such types of polluted water.

GENERAL TREATMENT PROCESSES

The propose treatment system and its components were designed on the basis of suitable site selection, total cost options and the effluents flow rate. To design the actual treatment system for a Combine effluent treatment plant (CETP), selection of a process train based on the capability of each treatment process unit, is required. Since the individual industries do not have the capability to carry out effluent treatment individually, therefore for combined effluent treatment the most important is determination of treatment efficiency, reliability and cost within the limitations of site and wastewater properties and treatment process selection. Topographic survey of the whole project area and its adjoining/surrounding areas (affecting the project area) depict all physical features required for the preparation of a proper base map for detailing planning and preparation of CETP. Soil characteristics are more important when some of the treatment options are being considered for CETP. Similarly the characteristics of wastewater are also important which include wastewater flow, minimum and maximum flow rate as well as anticipated future increases. For designing the size of plant depends on wastewater flow, usually expressed in the units of m3/day. Daily production mass of COD, BOD and TSS are designed to also account for the uncertainties of data and various assumptions for the analysis. The treatment process depends largely on industrial effluent that requires to be treated which is different from the municipal wastewater treatment. Therefore the physical, chemical and biological characteristics of wastewater could determine the size of CETP.

Fig. 5: Effluents of Hayatabad Industrial Estate Peshawar

The industrial effluents are leaving the HIE and passes through the settled areas of Peshawar and finally mixed with the water of River Kabul. The following methods will be used for the treatment of effluents of HIE.

The treatment of wastewater depend on the existence of organic non-biodegradable compounds, amount of toxic matters and

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(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016

A. Preliminary Treatment

pushed from the basin into the treatment flow channel to supplement the flow as desired.

Screening Equalization and Neutralization Grit Removal Scum removal through Skimming Tank

Grit Removal Grit removal is accomplished in channels or retention tanks. The objective is to settle out inorganic matter (particles with diameter above 0.2mm) whilst avoiding deposition of putrescible organic material. During this process, the organic matter must be kept in suspension. The average specific gravity of grit particles and organic matter are 2.5 and 1.2 respectively and therefore grit particles have a higher settling velocity than organic matter. The settling velocity of grit is approximately 0.03 m/s. The horizontal flow velocities in grit channels are normally 0.3m/s and higher horizontal velocities result in scouring of the deposited material. Grit settlement can therefore be used as a guide to the plant performance. If the quantity of grit reduces, it may be an indication that the flow rate has increased above 0.3 m/s or the grit is being retained in suspension 0.

B. Primary Treatment Sedimentation C. Secondary Treatment Activated Sludge Process Activated Carbon embedded in Sand Filter VII. PRELIMINARY TREATMENT Screening The effluents are collected by the primary and secondary drains and transported to combined effluent treatment plant. Large debris i.e. plastics, stones, cloths and pieces of glass are removed by passing it through screens. It helps to prevent the downstream assembly of CETP from the obstructions produce by solid matters. It is made of stainless steel to resist the corrosion and normally it installed at an angle (generally 30 or 60 degree) to the bed. Their opening are uniform to retain the solid matters. The removal of solid particles are determined by the screen spacing. Screening operation can be performed either automated or manually. If the flow rate is high or solid particles in large proportion are present then automated screening is preferred. While in manual screening, the deposited materials are removed by continuously scrapping the screens with mechanical rakes. The cross-section near the screen may be increased in order to achieve minimum velocity. The 5cm center to center opening screens are recommended for the effluents of HIE 0.

Scum removal through Skimming Tank The water is then discharged to an open ended rectangular, skimming tank through a pipe. The water flows across the tank by entering at the top of the tank from one side and ultimately making its way to a hole placed at the bottom of the side directly across from the entrance 0. The tank should have a volume of about 20 m3 to be able to handle the flow of water and to retain it for about 20 minute. A length and width of 3.16m and a height of 2m is required to observe the 2:1 ratio for the volume to surface area of the tank. VIII. PRIMARY TREATMENT Sedimentation

Equalization and Neutralization In the next step, the effluent is transferred to the primary clarifying tanks. Generally these tanks are very large, about 70m long and 15m wide. As the aerated fluid containing debris flows into the clarifying tanks, it is slowed down significantly to allow the remaining debris mixed in with the wastewater and to get separated from the genuine water. The material that settles down in the tanks is known as the primary sludge. They include solids, liquids, and semi-solids. The settling could be divided in to three types which are discrete settling, zone settling, and compression settling. When the effluent flows out of the primary sedimentation tank, the total amount of SS has been reduced by 35%-55% and the BOD has been reduced by about 17%-35% 0.

In a water or waste water treatment process, the flow equalization and chemical neutralization are two important stages. The first type of neutralization is used to balance the excess acidity or basicity in water, whereas the second type of equalization is a process to control flow velocity and its composition. Practically, the chemical neutralization is the adjustment of pH to gain the required treatment objective. In many Industrial as well as in municipal water treatment process, the flow equalization is done to reduce the severe variations in flow and water quality. Both of these processes have been used in wastewater treatment field for the last several decades. In any treatment system, the equalization basins may be located in-line or off-line. In first type, 100% incoming raw wastewater enters directly into the equalization basin, which is then pumped to other treatment units. However, for off-line equalization, the wastewater is not directly discharged to the basin but, an overflow structure diverts extra incoming flow from the incoming raw wastewater into the basin. Water is

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(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016

IX.

SECONDARY TREATMENT

X.

SLUDGE TREATMENT

In CETP, the sludge would be generated from the secondary settling tanks. No sludge digestion is proposed. The sludge, however, would need to be dewatered, in order to reduce its volume and to render it suitable for transportation for disposal or land application, as the case may be. The preferable method of sludge dewatering and drying, under local conditions, is sludge drying beds. These need, however, large area for their construction. In order to minimize the area requirement, mechanical dewatering of sludge is proposed. Many alternate technologies are available for sludge dewatering. For large installation, however, the most commonly employed technology, worldwide, is continuous belt-press filters. The sludge shall need to be thickened prior to its mechanical dewatering.

Activated Sludge Process The Activated Sludge Process (ASP) is most suitable effluent treatment process in which the effluents of any BOD desirable are produced. In this aerobic process the organic matter contained in the wastewater are decomposed rapidly by using microorganism. The amount of oxygen require for the growth of microorganism are supplied with aeration. The activated sludge are formed, when air is aerated for microorganism growth 0. The ASP consist of an aeration tank, where wastewater entered continuously into the tank. The air is introduced into the effluents for the purpose of mixing activated sludge with wastewater and also to supply the oxygen required for the microorganisms to decompose the organic compounds present in the effluents. The activated sludge and wastewater make a mixture known as mixed liquor. The activated sludge settle down, when the mixture flows into a secondary settling tank (SST). Some of the sludge from the SST is returned again to the aerated tank to achieve the maximum concentration of microorganism for the decomposition of the organic matters, the undesired sludge is wasted. Further treatment may be applied to the excessive sludge, either dewatered or digested. The treated effluent from the SST is released into a running river or on land 0. The ASP composed of clarifier, aeration tank and sludge treatment. The feed variation is reduced by keeping the wastewater uniform in equalization. The mechanical aeration is either used for the oxygen supply. In a wastewater treatment process the mixed liquor is released continuously, from the aerated tank to SST. If the solid retention period of ASP is within the limit of 4–10 days, then the efficiency of BOD removal is higher than 90%.

TABLE 2 DESIGN CALCULATIONS OF COMBINED EFFLUENTS TREATMENT PLANT DESIGN CALCULATIONS OF CETP Discharge Data De scription

Formula

Quantity

Units

8 2.5 20 0.57

ft³/sec (Factor of safety) ft³/sec m³/sec

Q/V

0.8 0.71

m/sec m²

Net Area × 6/5

0.85



Gross Area/0.866

0.98



1 17

m No's

0.3 1.89 1 1.89

m/sec m² m m

1.75 0.02 50 15

m/sec sec m

Flow rate Peak Factor Total. Discharge Total. Discharge 1) SCREENER Velocity Net Area 1 cm thick bar placed 5cm with Gross Area Bars are placed 60° inclined to horizontal Total Gross Area If 1 m is the height of screener Width of screener No. of bars 2) GRIT CHAMBER Velocity X- Sectional Area Height Width

Activated Carbon embedded in Sand Filter

Over all depth settling velocity Detention time Length of the tank

Carbon has the ability to absorb impurities. The use of carbon as impurities absorbent has an old history. The surface area of one pound carbon is approximately 125 acres, so hundreds of chemicals are absorb by carbon. Either powdered block carbon or granular activated carbon are typically used in activated carbon filters. The carbon block filters have greater pollutant removal efficiency. It involve two basic mechanism to treat the wastewater catalytic reduction and adsorption. The catalytic reduction remove the residual product i.e chloramine and chlorine and adsorption remove the organic compounds. The negative charge ions of contaminant are attracted by the positive charged carbon ion. It improves the water quality, eliminate or reduce the odors and bad taste.

Vh Q/V Area/Height Height depth above the crest free board Vs water depth/Vs Vh × Td

m

3) SKIMMING TANK Dimension of the tank

Length × Width × Depth

4) PRIMARY SEDIMENTATION TANK T. Discharge Amount of water supply per day Detention time Td Amount of water stored capacity of the tank If we suppose No of Tanks Capacity of single tank Depth of Tank Area of the Tank Capacity/Depth Flow Velocity Vf Length of the tank Vf × Td Width of the tank Area/Length Dimension of the Tank

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Length × Width × Depth

15m x 4m x 1.5m

0.57 48970 2 4081 2 2040 3 680 0.6 72 9.45

m³/sec m³/Day hr m³/Day No's m³ m m² m/sec m m 72m x 10m x 3m

(JETAE) Journal of Emerging Trends in Applied Engineering Vol. 1, No. 1, 2016 Description 4) AERATION TANKS T. Discharge Amount of water supply per day No of Tanks Capacity of single Tank (BOD)₅ Peak Load Factor (BOD)₅ Design value (BOD)₅ Effluent BOD Removal Efficiency

Formula

Capacity/4

Y0 YE Y0 -YE BOD Removal/Y0 × 100

MLSS F/M Detention Time F/M or V Depth of Tank Width of Tank Surface Area Length of Tank

Xi Td Q × Y0 /V × 2 × Xi Q × Y0 /(F/M × 2 × Xi)

A=V/Depth Surface Area/Width

Dimension of Aeration Tank 5) CLARIFIER T. Discharge Amount of water supply per day No of Tanks Capacity of single Tank Detention time Volume Depth of Thank Surface Area or

L×W×D

Units

ACKNOWLEDGMENT

0.57 48970 4 12242 112 2 224 20 204

m³/sec m³/Day No's m³/day mg/l

The data regarding’s to the Characteristics of Wastewater was given by “Creative Engineering Consultants Peshawar”. I am very thankful to Prof. Dr. M. Mahboob Alam, Chairman, Civil Engineering Department, INU, Peshawar for his continuous cooperation and guidance in writing this paper.

mg/l mg/l mg/l

REFERENCES

%

91 3000 0.14 12

mg/l mg/l hr

3265 3.5 15 933 62

m³ m m m m

[1] Sardar Khan, Asif and Noor, “Investigation of pollutants load in waste water of Hayatabad Industrial Estate, Peshawar” Pakistan journal of Applied Sciences, 2(4), pp 457-461, 2002. [2] Prashant A.kadu, Amruta, Dr. Y.R.M.Rao, “Treatment of Municipal Wastewater by using Rotating Biological Contractors” American Journal of Engineering Research Volume-2, Issue-4, pp-127-132, 2013. [3] S. Surumbar Kuzhali, N.Manikandan and R.Kumuthakalavalli, “Physico chemical and biological parameters of paper industry effluent” J. Nat. Prod. Plant Resource, 2 (3), pp 445-448, 2012. [4] Muthukumaran and Dr.N. K. Ambujam, “Wastewater Treatment and Management In Urban Areas – A Case Study of Tiruchirappalli City, Tamil Nadu, Third International Conference on Environment and Health, Chennai, India, 15-17 December, pp 284 – 289, 2003. [5] L. A. Terry, “Environmental law practice”, 4, 19, 1996. [6] Azizullah A, Khattak MN, Richter P and Hader, “Water pollution in Pakistan and its impact on public health”, Environ Int. Feb, 37 (2), pp 479497, 2011. [7] Muhammad Nafees, Asim Nawab and Wisal Shah, “Study on the performance of wastewater treatment plant designed for industrial effluents”, J. Engg. and Appl. Sci., Vol. 34, January – June, 2015. [8] S. Sirohi, S.P.S Sirohi and P.K. Tyagi, “Impacts of industrial effluents on water quality of Kali River in different locations of Meerut, India”, Academic Journal Vol.6 (4), pp.43-47, May 2014. [9] Kadam et al, “Characteristic of Industrial Effluents and their possible impact on Groundwater Quality”, Int. J. Res. Chem. Environ. Vol. 2 Issue 1, pp 124-129, January 2012. [10] F.K. Bangash, M. Fida and Fazeelat, “Appraisal of effluents of some selected industries of Hayatabad industrial estate, Peshawar”, Jour.Chem.Soc.Pak, Vol. 28, No.1, 2006. [11] Sultan et al., “Heavy Meatal status of industrial effluents and its impacts on Human life”, Jour.Che.Soc.Pak, Vol 30, 2008. [12] M. Tariq, M. Ali and Z. Shah, “Characteristics of industrial effluents and their possible impacts on quality of underground water”, Soil & Environ. 25(1), pp 64-69, 2006. [13] Melissa wason, Shreya, Danny dehon and Monique magee. “The wastewater treatment process” BE 3340, spring 2007. [14] Sanjeev Kumar Sinha, Vikas Kumar Sinha and Samir Kr. Pandey, “A study on the waste water treatment technology for steel industry”, American Journal of Engineering Research, pp 309-315, 2014.

62m x 12m x 3.5m

Capacity/4 Td V=capacity × Td D A=V/D (A × 4/3.14)ˆ½

Diameter

Quantity

0.57 48970 4 12242 2 1020 3.5 291

m³/sec m³/Day No's m³/day hr m³ m m²

19 20

m m

Influent (Raw Sewage) Secondary Treatment Preliminary Range Treatment

Primary Sedimentation

Biological Treatment

Final Sedimentation Tank

Secondary Sedimentation

Effluent

Sludge Treatment

Sludge Disposal

Fig. 6: Flow Diagram of Combine Effluent Treatment Plant

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