Green Island Cement

Our Tap Shek Kok cement plant operates under licenses issued from Environmental Protection Department. They cover emission limits at all fugitive dust emission point and the quality of wastewater disposed into the nearby reception zone. We also obtained a waste disposal license as the plant is a final disposal facility of treated Marpol (Marine Pollutant) waste. Monitoring equipment is installed to closely monitor our emission level to ensure that we completely comply with legal requirements. An effective environmental management system is adopted to ensure that our environmental policies are implemented effectively and any environmental problem is being addressed promptly.

The following environmental aspects and impacts are identified and are continuously addressed by our improvement plans:

Our Environmental Policy

What We Did to Protect Environment

Waste to Raw Materials

Flue-gas Desulphuric (FGD) Gypsum Program

A product of any coal fired combustion process is acidic gas. The common acidic gases are hydrogen chloride (HCl), nitrogen dioxide (NO2), and sulphur dioxide (SO2). If these acidic gases emitted to the atmosphere, they will damage the human respiratory system and cause harmful acid rain formation.

In order to deal with this pollution threat, flue gas desulphurization units (FGD) are installed in some power generation units to effectively remove this acidic gas. Green Island, using its expertise in mineral grinding, prepares a high quality limestone powder (CaCO3) for the power plant to use when it cleans up its flue gas.

The SO2 is converted into a sulphate salt called gypsum (CaSO4) by a neutralization reaction with limestone. FGD Gypsum is a solid waste from power plants and which would otherwise be disposed to landfill and become the burden to the environment.

Green Island conducted extensive research on this by-product FGD gypsum and by upgrading its facility; GIC recycles this FGD gypsum as a cement production additive to replace natural gypsum (which is used to control the hydration rate of cement). In fact, we consume nearly all synthetic waste gypsum in Hong Kong.

We employ the following recycled or industrial waste material as a substitute for our raw materials in the cement manufacturing process. In addition to FGD gypsum mentioned above, we also utilize other type of industrial solid wastes:

PFA

We pioneered the use of Pulverized-Fuel Ash ("PFA") in cement production in Hong Kong and southern China.

PFA is the ash residue after burning coal in power plants. PFA is usually disposed by dumping it into ash lagoons unless can be recycled. GIC provides a safe and environmentally friendly disposal for PFA produced by the utility companies in Hong Kong.

PFA is recycled as Aluminum ("Al") constituent in our clinker production process. It replaces the use of valuable natural resource of Bauxite and Clay. It is incorporated into the finish grinding process to produce Portland-fly ash cement (“PFAC”). The pozzolanic activity of PFA modifies the hydration mechanism of cement and provides improved durability.

Slag

Slag Material from blast furnaces and foundries is imported as a major iron (Fe) constituent to substitute the use of natural iron ore in the clinker production process.

Slag contributes 2% by weight in every tonne of our raw material used.

Unwashed Silica

Unwanted river sediment dredged for recovering river channels is recycled as our silica (Si) constituent in the manufacturing of clinker. It accounts for 9% of our raw materials used.

Crushed rock fine limestone (CRFL)

Limestone is a valuable mineral used extensively in various industries such as the steel refining industry, paper industry, as well as an aggregate in the construction industry. However, during the mining and processing of limestone for these applications, a fine residual portion is produced. GIC has upgraded its material handling facility to recycle this low value industry by-product in its clinker manufacturing process.

Waste Reduction

GIC cares for our environment we actively work at continuously improving our environmental performance. In so doing, GIC reduces both the need for natural resources and the production of waste. We aim to reduce waste through re-engineering to make recycling possible in our plant. We follow 3-R principles to reuse, recycle and reduce those wastes.

Waste includes:

Since 1997, we have achieved zero discharge in the following areas:

  1. Used brick and spillage are classified, crushed and recycled as raw material for the cement manufacturing process.
  2. An ultra-violet disinfection process is installed to replace the chlorination process, in the sewage treatment plant (STP). This enables the STP effluent to be used for plant irrigation.
  3. Rainwater is collected, stored and recycled for evaporation cooling at conditioning tower to improve the performance of electrostatic precipitators. As a result, we have reduced water consumption from 1,800tpd to 800tpd.

In addition, we have achievements in other types of waste:

  1. 2450kg used electronic components were reduced since 2013
  2. Less waste lube oil was generated since 2013

Air Pollution Control

GIC cares for our environment we actively work at continuously improving our environmental performance. In so doing, GIC reduces both the need for natural resources and the production of waste. We aim to reduce waste through re-engineering to make recycling possible in our plant.

Our production systems are totally enclosed to avoid generation of fugitive dust emission. Dust collector and EPs are installed to clean the dust-laden air before discharge to atmosphere.
Dust collected from dust collectors and EPs are returned to the production system. Any spillage on ground will be wet swept or vacuum and returned to production after sorting.

We work closely with the Authorities to improve our environmental performance through improvement plans and best practical measures ("BPM"). Here are a few examples on how we reduce our emission.

We voluntary replaced our Bromo trifluoro Methane (a green house gas) base fire fighting system by FM200.
We plan our product distribution network. Currently, 80% of our product is dispatched in bulk package which reduces the volume of packaging, and 40% of our product is dispatched by bulk barge carriers which reduces the pollution caused by road transportation.
We conduct research on dust collection technology. In 2002, we voluntarily reduced our fixed point “particulate” emission limits as compared to current BPM.

We adopt low NOx burner to reduce emission of NOx.

Proper control of combustion conditions to avoid over-heating of materials inside kiln, and maintain pre-calciner in slightly reducing environment.

We implement "No Smoking Policy" within the plant area both indoor and outdoor.

 

Water Conservation

Reduction of freshwater consumption by recycling domestic wastewater and rainwater. Domestic / recycled water used in:

Installation of low mist loss cooling towers for process water cooling.

Implement "Zero Wastewater Discharge Policy". Since 1997, we have achieved zero discharge of waster water.

Treat domestic wastewater by in-house treatment facility, retrofit with UV disinfection.

An ultra-violet disinfection process is installed to replace the chlorination process, in the sewage treatment plant (STP). This enables the STP effluent to be used for plant irrigation.

Water processing facility    UV disinfection system

Rainwater is collected, stored and recycled for evaporation cooling at conditioning tower to improve the performance of electrostatic precipitators. As a result, we have reduced water consumption from 1,800tpd to 800tpd.

Rain water pool

Energy Conservation

Through hardware improvement in one draft fan, we reduced electricity consumption by 7.8% in July 2015-June 2016 period when comparing to previous period.
In another improvement works in the finish mill, we reduced 2.4kWh per ton of cement produced by installing advanced liner plate inside the finish mill.

Finish Mill
We also change T5 fluorescent tubes to T8 and install timer control for lighting facilities.
T5 fluorescent tubes
When selecting products, we tend to use environmental-friendly products such as those with energy stars.
Encourage to set office temperature to 24-26C.
A pilot project for using solar energy to power lighting in our dock.
Solar panels at dock


Environmental Related Awards

Green Island Cement has awarded the BOCHK Corporate Environmental Leadership Awards 2016. The Federation of Hong Kong Industries (FHKI) joins hands with Bank of China (BOCHK) to organize ‘One Enterprise – One Year – One Environmental Project Program’ every year. It aims to promote environmental practices and reduce pollutions in Hong Kong & Pan Pearl River Delta region.

In 2016, around 530 participated enterprises had completed more than 1,000 projects in this region. As one of participants, we are delighted to have received Eco-Challenger Award (環保優秀企業) and 5 Years+ Eco-Pioneer Companies (5年+ 參與環保先驅獎章) on 1st June 2017.

 

Eco-Challenger Award 2016

Green Plus Awards 2016

CLP's Green Plus Award 2016 - Silver Award (Industry & Technology Category)

Award presentation for no smoke

SMOKE-FREE Leading Company Awards 2012