Environmental Impact Assessment on the Recycling of Waste LCD

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Environmental Impact Assessment on the Recycling of Waste LCD Panels Luling Yu, Yuichi Moriguchi, Jun Nakatani, Qian Zhang, Feng Li, Wenzhi He, and Guangming Li ACS Sustainable Chem. Eng., Just Accepted Manuscript • DOI: 10.1021/ acssuschemeng.9b00119 • Publication Date (Web): 22 Feb 2019 Downloaded from http://pubs.acs.org on February 25, 2019

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ACS Sustainable Chemistry & Engineering

Environmental Impact Assessment on the Recycling of Waste LCD Panels Luling YU1, Yuichi MORIGUCHI*2, Jun NAKATANI2, Qian ZHANG3, Feng LI1, Wenzhi HE*1, Guangming LI1 1State

Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution

Control and Ecological Security, College of Environmental Science and Engineering, Mingjing Building, Tongji University, 1239 Siping Road., Shanghai, 200092, P.R. of China. 2Department

of Urban Engineering, School of Engineering, the University of Tokyo, Hongo 7-3-1,

Tokyo, 113-8656, Japan. 3Department

of Civil Engineering, University of Victoria, Victoria V8P 5C2, Canada.

*Corresponding

author

E-mail Address: [email protected]; [email protected] Abstract: The waste liquid crystal display (LCD) panels are both harmful and reusable because of the variety of ingredients contained, for example, the liquid crystal, panel glass, and precious heavy metal. This study assumed one treatment technique which consists of crushing, hydrothermal process and acid-leaching to realize harmless treatment and resource recycling of waste LCD panels, basing on the previous experimental results in our lab. The environmental impacts of this treatment technique were evaluated by using two methods of life cycle assessment of ReCiPe 2008 and Eco-indicator 99 (EI’99). ReCiPe assessment results show that the adverse environmental impacts from the treatment process are dominated by the input of electricity which is followed by the use of hydrogen peroxide and kerosene. The treatment process brings positive impacts on the environment in the category of metal resource depletion but results in more pollution in categories of terrestrial acidification, human toxicity and

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particulate matter formation. EI’99 analysis reveals that, compared with incineration, the proposed treatment technique of waste LCD panels sharply cut down the negative environmental impacts by 91.5-97.3% under different scenarios. Keywords: Waste electrical and electronic equipment (WEEE); LCD panel; hydrothermal treatment; indium recycling; waste management; life cycle assessment (LCA)

Introduction The ever-increasing popularity of LCDs dramatically contributes to the generation of waste LCD devices because of short lifespan and fast updating of electronic products[1]. The statistics show that the shipment referring to only large-area TFT-LCD amounted to 683.5 million units worldwide in 2016[2] and the demand is expected to be around 217 million square meters in 2021[3]. As the core component of LCD, LCD panel attracts increasing attention after being discarded for its proper treatment, considering the large quantity and potential environmental hazards. LCD panel consists of two glass plates with liquid crystal molecules in between, and indium-tin oxide film etched on the inner sides of glass plates. Moreover, two pieces of polarizers are attached on the outsides of glass plates[4-6]. The heavy metals and organic ingredients, for example, the liquid crystal compounds which are aromatic-based polymers with benzene, are hazardous to the environment without proper treatment[7]. However, the precious metal of indium and glass substrates which account for 40-50 wt.% can both be recovered as secondary resource. Incineration and pyrolysis have been reported for treating the organic compounds in waste LCD panels owing to its easy-performing, after which the solid residue is further disposed of [8, 9]. However, the accompanying air pollution urges a greener treatment technique because of the harmful substances


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in flue gas[10-12]. Hydrothermal method is getting increasing interest in organic waste treatment to recover resource and dispose harmful waste by advantage of its high reactivity and green process [13-26]. It has been proved in our lab that polarizers can be effectively detached from panel glass and transformed into organic acids in hydrothermal system. The removal of organics of waste LCD panels facilitates the following recovery of indium and panel glass, in which indium can be recycled through hydrometallurgical process[27-29] and panel glass is proposed to be re-utilized as a construction material in concrete[30]. Therefore, the hydrothermal treatment, hydrometallurgical process and reutilization of panel glass are assumed as one combination for recycling waste LCD panels. Life cycle assessment has been widely applied in WEEE recycling analysis[31-34], which helps to optimize the WEEE flow analysis and reutilization process. This study assesses its environmental impacts and benefits by life cycle assessment (LCA), more specifically by methods of ReCiPe 2008 and Eco-Indicator 99 (EI’99), which is essential to evaluate its sustainable competitiveness compared with other techniques[35], Mid-point approach of ReCiPe 2008 is adopted to get an evaluation of 14 categories for detailed environmental impact. EI’99 is applied to compare the environmental impacts of the proposed technique with incineration.

Methodology Study object The assumed treatment technique consists of three parts: 1) crushing of waste LCD panels; 2) hydrothermal process; 3) recovery of indium. After being dismantled from waste LCD, the panels are first crushed into small particles which helps to enhance reaction efficiency in hydrothermal unit. Then, crushed panels are disposed under optimized hydrothermal conditions. After, the residue is treated via



the extraction of H2SO4-(Phosphoric acid, diethyl ester + sulfonated kerosene)-HCl to recover indium. The experimental conditions can be found in the publications of our lab[27, 36]. Goals and scope definition of LCA study Three goals are set: (1) to assess the environmental impacts of recycling waste LCD panels with technique proposed; (2) to identify the main impact categories and critical part of treatment technique; (3) to deliver scientific insights into improving the treatment technique. The scope of LCA in this study is gate-to-gate, i.e. from dismantled LCD panels to recovery of indium and panel glass, in which the separation of organic acid products is not included. The overview of defined system is shown in Fig.1. The functional unit is defined as 1 kg of waste LCD panels.

Figure 1 System boundary of LCA in this study

Data collection and life cycle inventory In this study, LCD panels are characterized by the content of organic carbon, glass and indium. The electricity input of crushing process is calculated based on mass and volume of LCD panels and the working capacity of crusher. Referring to functional unit, the optimized experimental conditions of our lab are scaled up for hydrothermal and acid leaching processes in two scenarios relying on the hypothesis that the reaction effect remains unchanged in amplified units. In scenarios 1, all parameters are scaled up with equal-ratio proportion. In scenarios 2, the liquid-to-solid ratio is half of that in scenario 1 while the other parameters keep same as scenario 1. Scenario 2 considers the converged scale effect on electricity usage from the lab level to firm-level practice. The input and output analysis of the treatment technique is shown in Fig.2.


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Figure 2 The input and output analysis of treatment technique proposed in this study

According to input and output analysis, life cycle inventory is listed in Table 1. Ecoinvent database v2.0 is referred for inventory analysis while some unavailable data in v2.0 is referred from ecoinvent online access. Table 1 The life cycle inventory of the whole treatment process of waste LCD panels.

Items

Volume

Density

Case 1：27.1898 MJ

Total quantity

Region/notes

7.5548 kWh

Electricity

China, mix electricity Case 2：15.9298 MJ

4.4283 kWh

0.6 L

1.1958 kg/L

0.7175 kg

Europe, 50% water solution, factory

Diesel

/

/

1.29×10-5 kg

V2.0 (online modification data)

Phosphoric acid (85%)

/

/

1.734×10-2 kg

Europe, 85% in water solution

Hydrochloric acid (30%)

10.60 mL

1.149 kg/L

12.1794×10-3 kg

Europe, 30% in water solution

Kerosene

200 mL

0.81 kg/L

0.162 kg

Europe, refinery

Sodium carbonate

/

/

4.21 ×10-3 kg

Global

Carbon dioxide

/

/

131.74 g

/

Indium

/

/

326.9868 mg

Europe

Silica sand

/

/

0.83 kg

Switzerland, construction materials

Hydrogen peroxide

solution (50%)



Life cycle impact assessment In this study, ReCiPe mid-point approach is applied for analyzing the detailed contribution of each input to environmental impact categories. Considering the relevance, 14 categories are chosen out of the 18 ones of mid-point approach, including climate change (CC), ozone depletion (OD), freshwater eutrophication (FEP), marine eutrophication (MEP), terrestrial acidification (TA), photochemical oxidant formation (POF), particulate matter formation (PMF), ionizing radiation (IR), freshwater ecotoxicity (FET), human toxicity (HT), marine ecotoxicity (MET), terrestrial ecotoxicity (TET), fossil depletion (FRD), and metal depletion (MRD). Besides, EI’99 is applied to give a more intuitionistic overview, in which the environmental impacts are summarized into three categories: human health, ecosystem quality and resource consumption. The normalization and weighting steps are performed to get the final value of total impacts for comparison.

Results and discussion Environmental impact assessment with ReCiPe method at the midpoint level (1) Impact on climate change The equivalent quantity of carbon dioxide (eq.CO2) is used to quantify the impact of treatment technique on climate change which causes greenhouse gas released. Two scenarios are compared in Fig.3(a) concerning all items in the inventory list. As shown, the eq.CO2 of case 1 and case 2 are respectively 9.62 kg and 6.02 kg for one functional unit. Additionally, the usage of electricity is the main contributor for both scenarios with 8.69 kg eq.CO2 and 5.09 kg eq.CO2. While looking into the data of mix electricity production in China derived


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from ecoinvent 2.0, 84.12% of the climate change effect is caused by the release of CO2 from the combustion of fossil fuel and 14.50% from methane release. Besides the input of electricity, the consumption of hydrogen peroxide (H2O2) solution is another main contributor to climate change. Counting all input for treating 1 kg of waste LCD panel with the technique proposed, the eq.CO2 caused by H2O2 usage is 0.88 kg, in which 84.26% is contributed by CO2 and 6.19% by methane both released from the combustion of fossil fuel in the production of H2O2. (2) Impact on particulate matter formation Suspended particulate matter not only decreases the atmospheric visibility but also harms human health. PM10, which is commonly known as inhalable particulates, is the atmospheric particulate matter with a dynamic diameter less than or equal to 10 μm. PM10 goes through respiratory system into human body, and during this process, the particulates with a dynamic diameter in the range of 5 μm to 10 μm can be stopped by the respiratory system while the ones less than 2.5 μm reach into alveolus pulmonis and then probably induces to cardiopulmonary function disorder[37-39]. In this study, the impact on particulate matter formation of the treatment of waste LCD panels is shown in Fig.3(b). As seen, electricity input is the dominant factor in particulate matter formation. For the two scenarios, PM10 contributed by electricity usage is respectively 23.60 g and 16.70 g. In addition to primary particulates, the SO2 and NOX released in mix electricity production may convert to secondary particulates after series of photochemical reactions in the air, for example the conversion of SO2 to sulphate. In this study, the secondary particulates coming from SO2 and NOX severally take up 51.06% and 24.70% of the total particulates amount resulted from the production of electricity. (3) Impact on terrestrial acidification



Terrestrial acidification refers to the process that the soil exposes to be acidic. The equivalent quantity of sulphur dioxide (eq.SO2) is used as an indicator to evaluate terrestrial acidification impact of products or processes. SO2 can get into soil system in the type of sulphate through atmospheric sedimentation, and then affects the soil pH. Fig.3(c) shows that electricity input is the leading reason for terrestrial acidification in treatment processes proposed. Eq.SO2 in scenario 1 is 75.80 g while eq.SO2 in scenario 2 is 44.40 g. As shown in Table 1, in this study, the environmental impact of electricity comes from the statistical data of mix electricity production in China. The existence of sulphur in coal explains the release of SO2. In the eq.SO2 caused by electricity, 79.55% comes from direct production of SO2 gas, and 20.30% is contributed by nitrogen oxide in the production of electricity.

Figure 3 The impact on climate change, particulate matter formation and terrestrial acidification from the treatment of waste

LCD panels with technique proposed

(4) Impact on water body eutrophication Water body eutrophication results from the excessive nutrients, that is the concentration of nitrogen and phosphorus in the water system is far beyond the safe level. In ReCiPe system, the freshwater eutrophication is indicated by the equivalent discharge of phosphorus (eq.P), and marine eutrophication is indicated by equivalent discharge of nitrogen (eq.N). As shown in Fig. 4, the freshwater eutrophication is mainly contributed by the usage of kerosene, H2O2 and electricity. In scenario 1, eq.P from treatment process of waste LCD panels is 7.85E-07 kg, in which the contribution ratio of kerosene, H2O2 and electricity is 1.48:1:1.87. Moving forward to


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scenario 2, the ratio is 1.48:1:1.09. The discharge of phosphorus during production processes of the three items indirectly leads to their impacts on freshwater eutrophication.

Figure 4 The impact on freshwater and marine eutrophication from the treatment of waste LCD panels with technique proposed

Different from freshwater eutrophication, the usage of electricity is the dominant factor for marine eutrophication. In scenario 1, eq.N from electricity input is 3.38E-07 kg, accounting for 92.07% of total eq.N. With less electricity input in scenario 2, the eq.N contributed by electricity usage decreases to be 1.98E-07 kg. The release of nitrogen oxides (NOX) is the main contributor to marine eutrophication. After being released into air, NOX can move with air transportation, attach to suspended particles, and then fall into surface water with rain and snow, which finally results in marine eutrophication[40]. (5) Impact on ionizing radiation Ionizing radiation refers to all radiation that can ionize substance, in which process one or several electrons are released from atoms, molecules, or other conditions of fetter. In ReCiPe, the impact on ionizing radiation is evaluated with the equivalent discharge of uranium 235 (eq.U235). The ionizing radiation impact of recycling LCD panels in this study is shown in Fig.5(a). In the whole treatment of waste LCD panels, the input of electricity and H2O2 are two dominant factors in ionizing radiation. In scenario 1, ionizing radiation contributed by electricity and H2O2 input are respectively equal to 170.00 g and 149.00 g of U235. In scenario 2, the ionizing radiation contributed by electricity decreases to be 99.80 g of eq.U235. For electricity and H2O2, the release of radon-222 in their production is the reason to explain that their input causes ionizing radiation. (6) Impact on photochemical oxidant formation



Photochemical oxidants are trace species which are formed during atmospheric photooxidation of volatile organic compounds and carbon monoxide[41]. In ReCiPe, the equivalent discharge of non-methane volatile organic compounds (eq.NMVOC) is used as the indicator to quantify the impact on photochemical oxidant formation. Fig. 5(b) depicts the general photochemical oxidant formation for treatment of waste LCD panels in this study. The eq.NMVOC for scenario 1 and scenario 2 are respectively 30.50 g and 18.80 g, and 93.11% of scenario 1 and 88.83% of scenario 2 are contributed by the NOX release in the production of electricity. (7) Impact on ozone depletion Methane, hydrocarbons and ethane released in the production of H2O2, electricity and other inputs may cause the ozone depletion. Therefore, the impact on ozone depletion of the treatment process is also evaluated with the indicator of equivalent Chlorofluorocarbon (CFC-11) production. Fig. 5(c) below shows the details of eq.CFC-11 release. The eq.CFC-11 for scenario 1 is 2.10E-07 kg, and that for scenario 2 is 1.90E-07 kg. Kerosene, H2O2 solution and electricity involved in the treatment process are three leading contributing factors for ozone depletion. Among that, eq.CFC-11 from H2O2 and kerosene is respectively 8.97E-08 kg and 7.41 E-08 kg for both scenarios. The eq.CFC-11 of H2O2 mainly comes from bromochlorodifluoro-methane (Halon 1211) released in its production, as well as the release of bromotrifluoro-methane (Halon 1301) and dichlorodifluoro-methane (CFC-12). 99.06% of eq.CFC-11 caused by kerosene is contributed by Halon 1301 generated in its production. In Fig.5(c), it is worth noting that the impact on ozone depletion from electricity usage is lower than H2O2 and kerosene. In scenario 1, the eq.CFC-11 from electricity is 4.82E-08 kg and 2.82E-08 kg


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in scenario 2. Similar to kerosene, the release of Halon 1301 during the production process is the main source of ozone depletion for electricity.

Figure 5 The impact on ionizing radiation, photochemical oxidant formation and ozone depletion from the treatment of waste

LCD panels with technique proposed

(8) Impact on ecotoxicity Four kinds of ecotoxicity are assessed in ReCiPe with a reference substance of chemical 1,4-dichlorobenzene (1,4-DB). In this study, the impact on ecotoxicity from treatment process of waste LCD panels is summarized in Fig. 6, including freshwater ecotoxicity, human toxicity, marine ecotoxicity, and terrestrial ecotoxicity. Among the four indicators, human toxicity is the most affected by the treatment process, 671.0 g of eq.1,4-DB in scenario 1 and 394.0 g in scenario 2. The impact on marine ecotoxicity is second to human toxicity. It can be figured out in Fig.6 that the terrestrial ecotoxicity exposes least impact, for which the eq.1,4-DB of scenario 1 is 303.0 mg and eq.1,4-DB of scenario 2 is 208.0 mg.

Figure 6 The impact on ecotoxicity from the treatment of waste LCD panels with technique proposed

Generally speaking, the input of electricity is the principal reason for the impact on ecotoxicity, especially human ecotoxicity. Additionally, eq.1,4-DB coming from usage of kerosene, phosphoric acid and H2O2 is also considerable. For freshwater ecotoxicity, the amount of eq.1,4-DB coming from kerosene usage is just next to that of electricity, which is followed by phosphoric acid and H2O2. For marine and terrestrial ecotoxicity, the usage of H2O2 is the second contributing factor. It is worth noting



that the recovery of indium and glass (shown as silica sand in this study) in the treatment process decreases the demand of raw indium and glass mining, which exerts a positive impact on ecotoxicity. That is why there is minus release of eq.1,4-DB in Fig.6. In the production of electricity, the discharge of bromine and arsenic is the main reason leading to freshwater ecotoxicity. Moreover, the discharge of arsenic, mercury and lead takes responsibility for human toxicity. Marine ecotoxicity caused by electricity input has various sources, including the release of arsenic, copper, vanadium, nickel, and bromine, etc. Copper, bromine, and nickel also contribute to terrestrial ecotoxicity. In addition, the discharge of phosphorus to the soil in the production of electricity is another reason for terrestrial ecotoxicity. The input of kerosene is also a key factor to ecotoxicity. In its production process, the elements of bromine and barium released into the surface river are the primary pollutants leading to freshwater ecotoxicity. The zinc ion released into marine system is the main reason for marine ecotoxicity. The element of bromine would get into marine directly or via the surface river, and furtherly affect marine ecotoxicity. The phosphorus into soil also accounts for the terrestrial ecotoxicity. The use of H2O2 would influence the freshwater ecotoxicity, human toxicity, marine ecotoxicity as well as terrestrial ecotoxicity through distinguished channels. It affects the freshwater ecotoxicity mainly through bromine discharging, affects the human toxicity mainly through arsenic, vanadium and lead releasing, affects the marine ecotoxicity mainly through air pollutants with vanadium and copper attached, affects terrestrial ecotoxicity mainly through the vanadium and phosphorus pollutants. In the four kinds of ecotoxicity, the input of phosphoric acid has the most visible impact on freshwater ecotoxicity, owing to the discharge of phosphorus in the production of hydrochloric acid.


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(9) Impact on fossil fuel depletion Fossil fuel depletion for treatment process is quantified with reference to kg-oil. As shown in Fig.7(a), the fossil fuel depletion of scenario 1 and 2 are respectively 2.16 kg and 1.47 kg oil. Oil depletion caused by electricity input takes the major part, accounting for 77.31% in scenario 1 and 66.67% in scenario 2. Preceded by electricity, H2O2 and kerosene contribute to fossil fuel depletion by 303.0 g oil and 195.0 g oil. Hard coal is the main power source for production of electricity. The coal consumption for producing electricity takes 92.81% of fossil fuel depletion caused by the input of electricity. Regarding the fossil fuel depletion caused by H2O2, gas and crude oil consumption in production of H2O2 respectively account for 57.43% and 25.61%. Crude oil is the raw material in production of kerosene. (10) Impact on metal depletion The recovery of indium is a crucial target of this treatment process. In ReCiPe system, there is no characterisation factor for connecting indium to the impact category of metal depletion. Therefore, in this study, the authors would like to assume this specific characterisation factor based on the characterisation factor of copper and the market price ratio of indium to copper. The total metal depletion of treatment process of waste LCD panels is shown in Fig.7(b) with reference to equivalent kg-Ferrum (eq.Fe). The recovery of indium and glass is environmentally beneficial to carry out the recycling of waste LCD panels. Phosphoric acid has more impact on metal depletion than other inputs by 2.02 g eq.Fe. The metal depletions of hydrochloric acid, kerosene and sodium carbonate are respectively 996.0 mg, 463.0 mg and 332.0 mg eq.Fe. However, indium is the substance recovered from waste LCD panels,



which influences environment positively and results in a negative value of metal depletion. As shown in Fig.7(b), the recovered indium is equal to -11.60 kg of Fe depletion. In addition to indium, the recovery of glass (silica sand) also exerts a positive influence on environment by -221.0 mg eq.Fe.

Figure 7 The impact on fossil fuel depletion and metal depletion from the treatment of waste LCD panels with technique

proposed

The above ReCiPe results indicate that environmental impacts are mostly contributed by the input of electricity, hydrogen peroxide and kerosene. Electricity consumption is the leading contributing factor in the 14 categories, excepting for ozone depletion and metal depletion. In addition, the recovery of indium and panel glass brings environmental benefit, especially referring to categories of ecotoxicity and metal depletion 3.2 Normalization analysis of the ReCiPe assessment results at midpoint level In order to compare the 14 impact categories by the unified unit (point, Pt), normalization is carried out at the ReCiPe midpoint level, which is shown in Fig.8.

Figure 8 The comparison of 14 impact categories after normalization

The categories of terrestrial acidification and human toxicity induced more impacts from the treatment of waste LCD panels than other categories in this study. Next to them, it is the particulate matter formation and fossil fuel depletion. The treatment process also influences climate change and marine ecotoxicity significantly. The positive impact on metal depletion by the recovery of indium is far more significant than the adverse impacts of other categories.


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Comparison between proposed treatment and incineration This study compares the potential environmental impacts of treatment technique proposed with incineration of waste LCD panels reported by Song etc[42]. Applying the same method of EI’99, the assessment results of two treatment techniques are summarized in Fig.9 (millipoint, mPt).

Figure 9 Results of proposed technique and incineration with EI'99

The impacts of scenario case 1 and case 2 of the hydrothermal-acid leaching technique are much higher than that of incineration regarding human health because of the electricity input for the proposed technique. In the production of electricity, the releases of particulate, sulfur dioxide, nitrogen oxides and arsenic are the four leading factors to cause negative impact on human health. But for ecosystem quality, the impact of incineration is far higher than that of case 1 and case 2, which is accounted by the discharge of gaseous pollutants in the incineration process. Moreover, the proposed technique shows a negative value in resource depletion because of the recovey of indium and reutilization of panel glass. In order to get an overview of the difference between hydrothermal-acid leaching technique and incineration, the average weighting factor is applied to normalize the results as shown in Table 2. The hydrothermal-acid leaching method sharply decreases environmental impacts of treating waste LCD panels in comparison with incineration, reducing 91.49% in case 1 and 97.32% in case 2. Table 2 The average weighting of environmental impact from different treatments of waste LCD panels.

Impact categories

Weighting factor

Case 1 (mPt)

Case 2 (mPt)

Incineratio(mPt)

Human health

40%

8.687E-01*40%

5.273E-01*40%

8.590E-02*40%

Ecosystem quality

40%

6.643E-02*40%

3.673E-02*40%

6.940E+00*40%



Resource

20%

Sum

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-6.747E-01*20%

-7.491E-01*20%

3.490E-02*20%

2.391E-01

7.580E-02

2.817E+00

Acknowledgement This work is supported by National Natural Science Fund Project (No. 21677111) of China and State Scholarship Fund of China Scholarship Council (File NO.201506260021).

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Graphic abstract



Figure 1 System boundary of LCA in this study


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Figure 2 The input and output analysis of treatment technique proposed in this study



Figure 3 The impact on climate change, particulate matter formation and terrestrial acidification from the treatment of waste LCD panels with technique proposed 126x242mm (300 x 300 DPI)


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Figure 4 The impact on freshwater and marine eutrophication from the treatment of waste LCD panels with technique proposed 220x77mm (300 x 300 DPI)



Figure 5 The impact on ionizing radiation, photochemical oxidant formation and ozone depletion from the treatment of waste LCD panels with technique proposed 128x257mm (300 x 300 DPI)


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Figure 6 The impact on ecotoxicity from the treatment of waste LCD panels with technique proposed 194x155mm (300 x 300 DPI)



Figure 7 The impact on fossil fuel depletion and metal depletion from the treatment of waste LCD panels with technique proposed 236x86mm (300 x 300 DPI)


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Figure 8 The comparison of 14 impact categories after normalization 244x169mm (300 x 300 DPI)



Figure 9 Results of proposed technique and incineration with EI'99 220x139mm (300 x 300 DPI)


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Environmental Impact Assessment on the Recycling of Waste LCD

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