Green Productivity Demonstration Program Hoang Thach & Sai Son Cement Company , Vietnam
Hoang Thach Cement Company, a state owned enterprise under Vietnam National Cement Corporation. It is one of the largest and most technologically advanced cement company in Vietnam. It has two lines of production with a total installed capacity of 2.3 million tons of cement/year. It employs around 2,700 employees who work on three shifts. Sai Son Cement Company is small-scale cement company using stationary vertical kiln production technology for cement production. It produces around 70,000 ton/year of clinker and 110,000 tons of cement and employs around 400 staff members. These two companies represent between them one of the most contrasting technology for cement manufacturing in Vietnam. It allows an assessment of how issues of scale of operation affect environmental and economic performance in the sector. It also allows an comparison between different cement producing technologies in Vietnam.
The future development strategy of both the companies is focused on enhancing the cement quality so as to meet the cement standards in the region and also cost reduction of the product. Beside this, Hoang Thach Cement Company plans to obtain ISO 14001 certification.
The GP team identified the following key areas of concern in Hoang Thach Cement Company, after conducting the initial environmental review.
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Dust: Measurement of dust showed Serious violation of Vietnamese industrial hygiene and air quality standards in crushing, kiln and packing areas. This not only caused bad working environment and health hazard for workers but also results in product loss.
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Waste Water : Waste Water is emanated primarily from unit 1 where around 8000 m3 of water is used for cooling of clinker and equipments. All the waste water except for sewage is discharged directly to Da Back river. The oil content in the waste water was also found to be on higher side.
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Noise: Noise is generated from equipment such as the limestone and clay crushers, air compressors, raw mill, kilns and cement mills. The noise generated in the compressed air section were 104-108 dB higher than the standard when 4 compressors were working.
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Low Productivity: Low productivity was of major significance in production line No.1 This is due to old technology of the satellite coolers of the kiln, pre-heater and crushing machine.
The key areas of concern in Sai Son Cement company are Dust, Noise and Low Productivity. This is mainly because of use of obsolete technology and poor housekeeping efforts within the company.
After detailed analysis of the production process and material balance the GP team identified 26 GP options in Hoang Thach Cement Company, out of which 17 were found to be appropriate for immediate implementation. The major GP solutions that were identified are listed below:
1. Water spraying on the trucks carry mined line stone and clay to reduce dust in unloading area.
2. Operation of 2 vacuum cleaner vehicles all along the transportation route to reduce dust, save clean water.
3. Special dust collection system for the conveyors to extract dust and collect it in the bag filters.
4. Change of bags with holes that are used for packing cement in line 1 to bags without holes.
5. Dust filter in system replaced by bag filter and in future to be replaced by ESP.
6. Collection of waste oil from vehicles in separate tank to be used in kiln.
7. Collect and burn all oily rays in kilns.
8. Waste water from vehicle washing to be treated in an oil separation system and then discharged.
9. Modify shape of lifting liner in a planetary clinker cooler in line 1.
10. Use of coarser raw material for kiln.
11. Reduce rock size by screening in the crushing machine by manually breaking of the larger size rock.
The Sai Son Cement Company with the assistance of cement expert and brainstorming between GP team members came out with 15 GP options. Out of these 7 options were found to be appropriate for immediate implementation. Some of the major options are listed below:
1. Reduction in dust emission in crushing of limestone by installation of cover. 
2. Installing a cover or construction of warehouse to keep clay and coal so as to reduce the moisture content in the pellets.
3. Increase the pellets diameter from 6-8 mm to 8-15 mm.]
4. Increase the burning efficiency of the clinker by relocating the air supply holes in the kiln.
5. Re-use the smoke from kiln in the dryer.
6. Re-designing the lifting liner of the milling machine to increase milling efficiency.
7. Improve the dust collection capacity in the packaging area to reduce dust exposure.
8. Increase the length of the sedimentation tank to reduce the suspended solid in the waste water.
9. Built a sound proof enclosure at noisy areas such as the milling machine.
10. Replace the open conveyor with a covered one from dryer to silo to reduce dust generation.
Hoang Thach Cement Company has implemented most of the immediately implementable GP solutions. It has also implemented EMS and has been awarded with ISO 14001 certificate. Sai Son Cement company is a small company with a small budget. It was not possible to implement all the suggested options immediately. To prioritize the options GP team used tools like brainstorming, cost benefit analysis and weighted sum method to select the feasible option for implementation.
The implementation of GP options has been successfully achieved, and at both the companies dust generation and water pollution has been reduced while increased efficiency of the equipment and procedures have been achieved. Waste oil is now reused as fuel in the kiln and a solid waste collection system has been setup. Especially, an EMS was established in Hoang Thach Cement Company, which will enable the GP implementation in the company to be sustainable. Another GP option implemented at Hoang Thach Cement Company was a dust collection equipment at the junction of the two conveyors. This resulted in savings of 4 tons cement/month with an investment to 100 Million Vietnamese Dong ( US $ 6410 )and a payback of 10 months. The sustainability of the program also derives from the improvement in the awareness of the employees of both the companies regarding Green Productivity.
The Green Productivity Program has been successfully implemented in the two large and small cement companies in Vietnam. The results achieved have contributed significantly to the improvement of the environmental performance of both the factories and have additionally positive impacts on their efficiency .
Hoang Thach Cement Company, a state owned enterprise under Vietnam National Cement Corporation. It is one of the largest and most technologically advanced cement company in Vietnam. It has two lines of production with a total installed capacity of 2.3 million tons of cement/year. It employs around 2,700 employees who work on three shifts. Sai Son Cement Company is small-scale cement company using stationary vertical kiln production technology for cement production. It produces around 70,000 ton/year of clinker and 110,000 tons of cement and employs around 400 staff members. These two companies represent between them one of the most contrasting technology for cement manufacturing in Vietnam. It allows an assessment of how issues of scale of operation affect environmental and economic performance in the sector. It also allows an comparison between different cement producing technologies in Vietnam.
The future development strategy of both the companies is focused on enhancing the cement quality so as to meet the cement standards in the region and also cost reduction of the product. Beside this, Hoang Thach Cement Company plans to obtain ISO 14001 certification.
The GP team identified the following key areas of concern in Hoang Thach Cement Company, after conducting the initial environmental review.
-
Dust: Measurement of dust showed Serious violation of Vietnamese industrial hygiene and air quality standards in crushing, kiln and packing areas. This not only caused bad working environment and health hazard for workers but also results in product loss.
-
Waste Water : Waste Water is emanated primarily from unit 1 where around 8000 m3 of water is used for cooling of clinker and equipments. All the waste water except for sewage is discharged directly to Da Back river. The oil content in the waste water was also found to be on higher side.
-
Noise: Noise is generated from equipment such as the limestone and clay crushers, air compressors, raw mill, kilns and cement mills. The noise generated in the compressed air section were 104-108 dB higher than the standard when 4 compressors were working.
-
Low Productivity: Low productivity was of major significance in production line No.1 This is due to old technology of the satellite coolers of the kiln, pre-heater and crushing machine.
The key areas of concern in Sai Son Cement company are Dust, Noise and Low Productivity. This is mainly because of use of obsolete technology and poor housekeeping efforts within the company.
After detailed analysis of the production process and material balance the GP team identified 26 GP options in Hoang Thach Cement Company, out of which 17 were found to be appropriate for immediate implementation. The major GP solutions that were identified are listed below:
1. Water spraying on the trucks carry mined line stone and clay to reduce dust in unloading area.
2. Operation of 2 vacuum cleaner vehicles all along the transportation route to reduce dust, save clean water.
3. Special dust collection system for the conveyors to extract dust and collect it in the bag filters.
4. Change of bags with holes that are used for packing cement in line 1 to bags without holes.
5. Dust filter in system replaced by bag filter and in future to be replaced by ESP.
6. Collection of waste oil from vehicles in separate tank to be used in kiln.
7. Collect and burn all oily rays in kilns.
8. Waste water from vehicle washing to be treated in an oil separation system and then discharged.
9. Modify shape of lifting liner in a planetary clinker cooler in line 1.
10. Use of coarser raw material for kiln.
11. Reduce rock size by screening in the crushing machine by manually breaking of the larger size rock.
The Sai Son Cement Company with the assistance of cement expert and brainstorming between GP team members came out with 15 GP options. Out of these 7 options were found to be appropriate for immediate implementation. Some of the major options are listed below:
1. Reduction in dust emission in crushing of limestone by installation of cover.
2. Installing a cover or construction of warehouse to keep clay and coal so as to reduce the moisture content in the pellets.
3. Increase the pellets diameter from 6-8 mm to 8-15 mm.]
4. Increase the burning efficiency of the clinker by relocating the air supply holes in the kiln.
5. Re-use the smoke from kiln in the dryer.
6. Re-designing the lifting liner of the milling machine to increase milling efficiency.
7. Improve the dust collection capacity in the packaging area to reduce dust exposure.
8. Increase the length of the sedimentation tank to reduce the suspended solid in the waste water.
9. Built a sound proof enclosure at noisy areas such as the milling machine.
10. Replace the open conveyor with a covered one from dryer to silo to reduce dust generation.
Hoang Thach Cement Company has implemented most of the immediately implementable GP solutions. It has also implemented EMS and has been awarded with ISO 14001 certificate. Sai Son Cement company is a small company with a small budget. It was not possible to implement all the suggested options immediately. To prioritize the options GP team used tools like brainstorming, cost benefit analysis and weighted sum method to select the feasible option for implementation.
The implementation of GP options has been successfully achieved, and at both the companies dust generation and water pollution has been reduced while increased efficiency of the equipment and procedures have been achieved. Waste oil is now reused as fuel in the kiln and a solid waste collection system has been setup. Especially, an EMS was established in Hoang Thach Cement Company, which will enable the GP implementation in the company to be sustainable. Another GP option implemented at Hoang Thach Cement Company was a dust collection equipment at the junction of the two conveyors. This resulted in savings of 4 tons cement/month with an investment to 100 Million Vietnamese Dong ( US $ 6410 )and a payback of 10 months. The sustainability of the program also derives from the improvement in the awareness of the employees of both the companies regarding Green Productivity.
The Green Productivity Program has been successfully implemented in the two large and small cement companies in Vietnam. The results achieved have contributed significantly to the improvement of the environmental performance of both the factories and have additionally positive impacts on their efficiency .
