Environmental assessment for paper and cardboard industry in Jordan — a cleaner production concept

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  • Journal of Cleaner Production 12 (2004) 321326www.elsevier.com/locate/jclepro

    Environmental assessment for paper and cardboard industry inJordan a cleaner production concept

    Ghaleb Y. Abbasi a, Bassim E. Abbassi b,a Industrial Engineering Department, Faculty of Engineering & Technology, University of Jordan, Amman, Jordan

    b Department of Water Resources & Environmental Management, Al-Balqa Applied University, Al-Salt, JordanReceived 24 April 2001; accepted 27 March 2002

    Abstract

    An environmental assessment for Jordan Paper and Cardboard Factory (JPCF) was conducted. Cleaner production concept, whatit can achieve, and how it can be applied to JPCF was tested. Using the waste audit tool, five independent options were identifiedas having potential for improvements; these were on site reuse, technological changes, raw material changes, good housekeeping,and product changes. For each option, one or more pollution prevention actions were recommended. Economical advantages thatcould be achieved in water, energy, and material savings were quantified and simple payback periods calculated. Analyses revealedthat on-site reuse and technological changes were the most efficient environmental options. Although different actions might resultin similar benefits, the decision to execute a certain action is dependent upon its economic viability. 2002 Published by Elsevier Ltd.

    Keywords: Cleaner production; Environment; Paper and cardboard; Water; Energy; Jordan

    1. Introduction

    The protection of the eco-systems to ensure theworlds productive capacity requires environmentallysustainable forms of development. This is becoming animportant issue in view of the limited global resourcesand increasing population and industrialization. In thelast decade, many Jordanians have become aware of thenational resource base limits and pollution of water, soil,and air.

    In general, the paper industry consumes great quan-tities of natural resources, especially water and energy.Thus, it has significant impacts on the environment. Itgenerates large volumes of wastewater that adverselyaffects fresh water resources. Water pollution from thepulp and paper industry includes suspended solids, bio-chemical oxygen demand (BOD), toxicity, and color[4,7,8].

    Paper characteristics mainly depend on the rawmaterial used for pulp production, which might be agri-

    Corresponding author. Fax: +962-5-353-0469.E-mail address: babbassi@bau.edu.jo (B.E. Abbassi).

    0959-6526/$ - see front matter 2002 Published by Elsevier Ltd.doi:10.1016/S0959-6526(02)00047-1

    cultural residues, waste paper, or other non-woodmaterials. Research and development activities are cur-rently being performed in developed countries toimprove the quality of waste-based papers, less work isbeing done in developing countries [Danforth, 2000].Due to Jordans limited agricultural resources, wastepaper represents the main raw material source used incardboard manufacturing.

    The main objective of this research was to prepare anenvironmental assessment for Jordan Paper and Card-board Factories (JPCF) by implementing cleaner pro-duction concepts based on an integrated preventiveenvironmental strategy. This was achieved by identifi-cation of different options and their related pollution pre-vention actions to increase eco-efficiency and reducerisks to humans and the environment.

    2. Methodology

    Cleaner production is the continuous application ofan integrated preventive environmental strategy appliedto processes, products, and services in order to increaseeco-efficiency and to reduce risks to humans and the

  • 322 G.Y. Abbasi, B.E. Abbassi / Journal of Cleaner Production 12 (2004) 321326

    environment. Some cleaner production approachesinvolve modifications to existing systems and processes,others involve entirely new and innovative methods ofproducing products or services that leap-frog over exist-ing technologies in terms of their environmental per-formance [6].

    The waste audit tool used in this research consistedof three phases; pre-assessment, input-output analyses,and synthesis. The process elements for cleaner pro-duction options consist of: on-site reuse, technologicalchanges, changes in input materials, good housekeeping,and product change [1,2].

    3. Phase one; pre-assessment

    JPCF manufactures corrugated boxes for agriculturaland industrial purposes with an annual full capacity of40,000 tons of sheets and 15,000 tons of corrugatedboxes. The company has two major production units,paper and cardboard, with the second being an assemblyline for the first [3].

    Waste paper is used as the raw material and is boughtat two prices: either from the source at 30 USD/ton, orhauled by factorys trucks at 23 USD/ton. Certainimported fibers are bought to prepare the virgin pulp ata price of 450 USD/ton. The annual production of 9600tons represents 24% of the plants capacity requiring11,520 tons of raw material [3]. Waste paper arriving atthe factory is inspected and sorted to eliminate undesir-able materials such as plastic and metal. Finally, it ispressed into bales and stored in bunkers or sent directlyto the mill.

    Cardboard manufacturing produces wastewater calledwhitewater that is reused in paper processing. White-water might contain significant BOD and is always asource of suspended solids. The amount of fresh waterused for cooling of pumps is 10801100 m3/day, withan annual consumption of 396,000 m3 and annual costof about 138,000 USD.

    After processing, fresh and whitewater are collectedin a main channel. Screening downstream of the mainchannel is done to separate fibers from whitewater andto return the fibers to the pulper machine production line.Water flows to a sand trap (grit chamber) for furthercollection of suspended solids. Water is then pumped tothe flotation tank, a unit operation that is used to separatesuspended solids that escaped from preceding units.Supernatant water is pumped into the factorys waste-water treatment plant that consists of two lagoons. Inthe first lagoon, biological treatment is enhanced usingsurface aeration, while the second lagoon serves as amaturation unit where effluent water is reused in the pro-duction processes.

    In addition to water, electricity and fuel are also usedin the production process. Electricity is bought at 0.041

    USD/kWh. The hourly consumption rate is approxi-mately 1580 kW, which results in an annual cost of563,400 USD. Fuel is bought at 102.1 USD/ton and con-sumed at a rate of 9 tons/day, which results in an annualconsumption rate of 3240 tons, and an annual cost of330,845 USD.

    JPCF owns six trucks for waste paper transportationwith 5 and 2.5 ton capacities, two buses, and other hau-ling equipment with a monthly diesel fuel consumptionof 1000 liters. Table 1 summarizes the annual consump-tion of the above-mentioned resources.

    3.1. Phase two; inputoutput analyses

    The production process inputs and outputs were ana-lyzed to comprehensively identify improvement opport-unities [1]. It concentrated on water usage in differentproduction units, where the main sources of wastes andthe major opportunities for improvement exist. Table 2depicts inpu{n}toutput analyses for specific parts of theprocess based mainly on the percentages of water pro-duced by each production unit.

    The consumption of energy for each subunit in theprocess is presented in Table 3 showing the rate ofenergy consumption in kWh and daily working hours.

    3.2. Phase three; synthesis

    This is the third tool in the waste audit used to deter-mine the weak points in the system. Subsequently,detailed process modifications are discussed in the nextcleaner production options and benefits section. Basedon the previous analyses, the major improvement poten-tials are in: process water consumption, wastewater gen-eration, wastewater treatment plant, energy consumption,and raw material usage.

    Two actions were considered to create an opportunityin water saving. Water is evaporated at a rate of 10 m3for each ton produced, with an annual water loss of115,200 m3 and a cost of 40,300 USD. Second, 396,000m3/year of fresh cooling water are mixed with pollutedwhitewater with an annual cost of 138,000 USD. In thecontext of environmental pollution prevention, weakpoints analyses for six focus locations were consideredand are presented in Table 4.

    Observations and analyses of the wastewater treat-ment plants showed that the thick sludge cake thataccumulates over the lagoon, causes failure in the bio-logical treatment system. Table 5 shows the results ofwater analyses taken from the six different locationsmeasuring the main pollution parameters: chemical oxy-gen demand (COD), biochemical oxygen demand(BOD), and total suspended solids (TSS).

    Certain rearrangements could be considered in thewastewater sewer system that could contribute to solvingmany weak points in the system. Mixed or separate

  • 323G.Y. Abbasi, B.E. Abbassi / Journal of Cleaner Production 12 (2004) 321326

    Table 1Resource consumption by the JPCF

    Resource Water (m3) Electricity (kW) Fuel (ton) Diesel (L) Raw material (ton)

    Annual consumption 396,000 13,651,200 3240 12,000 11,520Unit price (USD) 0.35 0.041 102.1 0.15 23.0Annual cost (USD) 138,000 563,400 330,845 1800 264,960

    Table 2Water percentage in the different paper production units of JPCF

    Process Paper % Water %

    Pulper 4.5 95.5High density cleaner 4.0 96.0Ultra screen 3.5 96.5Fiber separator 2.5 97.5Low density cleaner 1.0 99.0Vacuum pumps 20.0 80.0Pressers 45.0 55.0Dryer 93.0 7.0

    sewer decisions should be taken in different points inthe system. The two main treatment units; the flotationprocess and the aeration mixers consume 60 and 45 kWhrespectively, with an annual electrical consumption of907,200 kWh and a bill of 37,055 USD. Process modifi-cations to reduce energy consumption are presented anddiscussed in the next section.

    Up to 20% of the raw materials flow into the waste-water treatment plant during the production processes.In addition to the large material loss, this causes sludgebuild-up over the first lagoon and reduces the treatmentprocess efficiency. Modifications can be considered inorder to minimize the loss of raw material and the sludgeaccumulation problem, as presented next.

    The factory does not have a de-inking technique andthe excess effluent water, which is used for irrigationpurposes could have negative impacts on the environ-ment threatening the agricultural life and groundwaterquality [3].

    4. Cleaner production options and benefits

    Five focal options and pollution prevention opport-unities were recommended. Several of the suggestedimprovement options are independent, meaning that aredesigned system can have one or more combinationsof the different options. Achieving the optimal solutionis highly dependent on several external and internal con-ditions. Table 6 summarizes the recommendations andidentifies their environmental benefits, estimated costs,annual expected benefits, and simple payback periods.

    Table 3Energy consumption of different units in JPCF

    Process kWh Working Daily energy(hours/day) consumption

    (kWh)

    Bale conveyor 7.5 8.0 60.0Pulper 250.0 24.0 6000.0Stock pump #1 15.0 8.0 120.0Propeller agitator #1 20.0 24.0 4800.0Stock pump #2 20.0 8.0 160.0High density cleaner 5.5 8.0 44.0Propeller agitator #2 20.0 24.0 480.0Stock pump #3 25.0 8.0 200.0Double discrifiner 132.0 24.0 3168.0Propeller agitator #3 20.0 24.0 480.0Stock pump #4 30.0 16.0 480.0Ultra screen 45.0 24.0 1080.0Stock pump #5 22.0 24.0 528.0Fiber separator 37.0 24.0 888.0Stock pump #6 15.0 24.0 360.0Propeller agitator #4 15.0 24.0 360.0Propeller agitator #5 15.0 24.0 360.0Stock pump #7 30.0 10.0 300.0Stock pump #8 15.0 24.0 360.0Low density cleaner 10.0 24.0 240.0Vertical screen 15.0 24.0 360.0Vibrating screen 1.1 24.0 26.4Top head box 5.0 24.0 120.0Filler head box 5.0 24.0 120.0Top wire vacuum pump 37.0 24.0 888.0Filler wire vacuum pump 37.0 24.0 888.0Couch roll vacuum pump 90.0 24.0 2160.0Pressers 295.0 24.0 7080.0Boilers 70.0 24.0 1680.0Soft calendar 48.0 24.0 1152.0Cooling roll 12.0 24.0 288.0Calendar roll 74.0 24.0 1776.0Pop roll 23.5 24.0 564.0Winder 10.0 24.0 240.0Aeration mixer 45.0 24.0 1080Flotation process 60.0 24.0 1440.0

    4.1. On-site reuse

    The high rate of consumption of fresh water, approxi-mately 33,000 m3/month, results in an annual water con-sumption of 396,000 m3. Considerable reduction can beachieved if the following two points are considered:

    1. Condensation of steam generated from the drying unit

  • 324 G.Y. Abbasi, B.E. Abbassi / Journal of Cleaner Production 12 (2004) 321326

    Table 4Focus location for weak point analysis

    Location Description

    1 Discharged water from the cooling process2 Effluent water from the flotation process3 The overflow from the factory water not entering the

    flotation processes4 Water used in the pulper5 Water from beneath the production wires6 Water from the second lagoon

    Table 5Results of water analyses from six different locations within the JPCF

    Location 1 2 3 4 5 6

    COD (mg/l) 679.7 906.2 1151.6 2832.0 2879.2 849.6BOD5 (mg/l) 79.5 82.0 175.0 329.0 200.0 93.0TSS (mg/l) 231 65 470 1076 1160 77

    process through a fully enclosed hood over the dryerscan result in an annual saving of about 40,300 USD.

    2. Separation of the two streams of the pumps coolingwater and whitewater could save 396,000 m3 annu-ally. This would enormously reduce overall waterconsumption.

    Reuse of wasted raw materials can be achieved byintroducing fine and coarse screening for the overflowstream channel. The collected suspended fibers wouldreduce the raw material losses at the source and are

    Table 6Summary of cleaner production options and potential benefits for the JPCF

    Option Pollution prevention action Actual benefits Estimated costs Annual benefits Payback period(USD) (USD) (Months)

    1. On-site reuse Steam condensation by Water savings 10,000 40,300 3enclosed dryers hoodWater stream separation Water saving 58,000 138,000 5Fine & coarse screening Raw material reuse 50,000 48,000 12.5Sludge layer removal Reuse as fuel 30,000 30,000 12

    2. Technological change Treatment plant modification Increase treatment 20,000 16,000 15efficiency

    Replacement of floatation tank Increase treatment 2000 48,000 0.5pump efficiency & raw material

    reuse

    3. Raw material change Modification of sorting & Improve production quality 5000 30,000 2collection system

    4. Good house keeping Shelters & pavement for Raw material Protection & 25,000 26,500 11.5storage area loss minimizationRedesign truck routes Fuel consumption 3000 900 40

    reduction & increasetransportation efficiency

    5. Product change Implement de-inking process Improve product & 15,000 60,000 3irrigation water quality

    reused in the production process. Regular screen clean-ing has to be done in order for the system to operateeffectively; then the collected fibers can be re-pulped.With an estimated cost of 50,000 USD for constructionof the fine screening unit operation and an annual benefitof 48,000 USD, the payback period is estimated at12.5 months.

    The accumulated sludge over the first la...

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