Monday, 15 April 2013

Proper storage of chemical waste

Under the Waste Disposal Ordinance (Cap.354) - Waste Disposal Regulations, Hong Kong Environmental Protection Department has defined chemical waste as any substance or thing being scrap material, effluent, or an unwanted substance or by-product arising from the application of or in the course of any process or trade activity, and which is or contains any substance or chemical specified in the prescribed schedule if such substance or chemical occurs in such form (, quantity or concentration so as to cause pollution, constitute a danger to health or risk of pollution to the environment.

Chemical waste should be properly and temporarily stored by the waste producer before the waste is transferred by the waste collector to a licensed treatment provider. There are certain criteria should be applied to the containers for temporary chemical waste storage, including its material, condition, etc. Such containers should be placed in a suitable area located close to the waste generation source for temporary storage and the containers should be either drums or jerricans type. The size of the containers should be determined according to the quantity and frequency of chemical waste to be stored. Common types of materials to be used for the containers include plastics and steel.

The storage area should be enclosed on at least three sides by partition, wall or fence with a height of not less than two metres or the total height of containers in stack, whichever is less. Such enclosures should be built with concrete, brick of steel with fixed erection to the areas. In addition, appropriate labeling should also be applied for accurate indication to ensure proper and safe handling, storage and transport of the waste.

Source: Hong Kong Environmental Protection Department

For specific details regarding Hong Kong Environmental Protection Department's guideline of chemical waste storage, please visit:


根據“廢物處置條例”(第354章) - “廢物處置條例”,香港環境保護署界定化學廢物為應用於或進行任何工序或活動期間所產生的廢料、廢水或無用的殘餘物質或副產品,而此等物品中,含有規例附表內開列的物質或化學物品 (,而其形態、份量及濃度又足以危害人體健康或污染自然環境。





Impacts of oil to us

Lubricants are used in many types of machinery during the day-to-day operation in various industrial and commercial activities. Used oil is, simply put, any oil that has been refined from crude oil and such use leads physical and/ or chemical contamination. During normal use, Impurities including dirt, metal particles, water, as well as other chemicals may be blended in with the oil, causing diminishing performance. These lubricating oils are classified as a type of chemical waste because it has been proven to have severe adverse impacts on the environment if dispose of improperly.

Chemistry of oil

Petroleum and its related products are made up with hydrocarbons, which are by its name, compounds containing both carbon and hydrogen. The simplest molecule of hydrocarbon is methane, the main component of natural gas. With the extension of additional carbon and hydrogen atoms, longer chains will be formed. In the case of lubricating oils, each molecule contains from 20 to 70 carbon atoms. These molecules are found to be particularly stable and will never be diminished. That is to say, replacing depleted additives within the oil is the key and crucial step to refine the used oil.

Impacts to environment and human health

Numerous toxic substances are found in spent oil, these toxins are uneasy to be degraded once enter the environment. For instance, polycyclic aromatic hydrocarbons found in used motor oil have been proven to be a carcinogen. Tiny metal scrapings from the engine compartment such as lead, arsenic, and zinc will also blended into the oils during operations. In addition, exposure to heat during engine combustion will also alter the chemical structures of the oil. Leakages, spillages, or improper handling of lubricating oils will enter the local water bodies unavoidably, through manmade drains or channels to streams, rivers, lakes, underground water tables and even reaching the ocean. At the end of the day, poisoning our drinking water sources and marine animals that we may consume ourselves.






廢油內含有大量的有毒物質,一旦進入環境,將不易被降解。比如,車用機油中含有一種碳氫化合物 - 多環芳烴 (PAH),已被證實是一種致癌物質。在機器的發動過程中,引擎的細小金屬碎屑如鉛、砷、鋅等也會混入油中。而因發動所引起的熱力也會改變油的化學結構。若滲漏、溢出、或處理不當,廢油及其內的有毒物質將會進入水體,經雨水渠、溪流、河流、湖泊、或地下水源,最後流入海洋,污染我們的飲用水源和毒害海洋生物,到最後,受害的可能都會是我們自己。

Emergency chemical and oil spill cleanup service

Risk management has now becoming an important component for many corporations nowadays, in different operation units. In recent years, Dunwell has been providing one–stop chemical waste management to government departments, public enterprises, and transportation-related industry. In particular, we offer emergency spill clean up standby service which is tailor-made for our clients who require specialized emergency response and spill clean up service.
On request, our team will be at standby status; upon occurrence of contingencies such as chemical spillage and/ or oil leakage, our team will then provide immediate and fast response to perform remediate services that can remove the pollutants and restore the original conditions. Our professional teams are well trained and have the expertise in treating chemical waste and oil spill, we provide our customers with round-the-clock and one-stop service to solve contingent spillage at any time, allowing clients to focus on their own business and operations. Our solution can greatly reduce the financial or reputational loss caused by both man-made and natural chemical spillage, which helps clients to achieve a better corporate social responsible standard.




Hong Kong says YES to waste charging scheme

Establishing a proper waste management system has always been a challenging task for the Hong Kong government to implement. Back in 1995, the government has proposed to introduce a waste charging scheme to provide a financial incentive for the public to reduce waste generation. However, this proposal has been staying in the research and discussion stage until Jan 2012, when the Environment Bureau has launched the public consultation on the introduction of waste charging to reduce the generation of municipal solid waste.

Four suggested approaches have been included In the consultation document, including quantity-based system, proxy system, fixed charge system, and partial charging system. The result of the consultation revealed that over 60% of written comments received support waste charging scheme and over 50% is in favour of the quantity-based system. In Dec 2012, the government has outlined the initial framework of the waste charging scheme. The preliminary proposal goes in line with what the majority in favour of: quantity-based system to be established in 2016.

Yet, details including charging standards and methods have not yet been confirmed. Using the case of Taipei as a reference, it is predicted approximately HK$40 will be charged monthly for a family of three. However, with the effort of source reduction and recycling, the cost can be reduced to $30/month.

MSW collection services in Hong Kong are delivered with an emphasis on efficiency and high hygiene standards. Our waste collection system and network have not been operated in a way that can facilitate the collection of a quantity-based waste charge; neither does it facilitate waste tracing. In the event that the implementation of charging is unsatisfactory, illegal dumping might arise and could have an impact on environmental hygiene.

When Taipei first launched the waste charging scheme, its adherence rate was over 99.5% and illegal dumping still existed. Once establishing the waste charging scheme, fewer garbage bills will be placed on the public areas and increasing illegal dumping is expected. The second phase of consultation will be launched in the near future to address the consequences of waste charging scheme and to identify possible solutions to avoid illegal dumping.

In fact, there has been voices pointing out there are excessive quantity of garbage bins in Hong Kong. In one way, it provides a convenient way for our citizens but also spoiling them. In some urban districts, the ratio of garbage bin to recycling bin is 1:20. To tackle the root factor, it is suggested that more recycling bins and fewer garbage bins should be placed along the public areas to help the Hong Kong citizens to develop a good recycling habit.








Safety regulations updated

Safety has been one of Dunwell’s major focus areas through out the years; we regularly provide safety training to our employees and sub-contractors to develop and increase their awareness of occupational health and safety. At the same time, we also subsequently conduct review and modification to our existing policies and work-related procedures for safety enhancement.
Each interceptor usually contains more than one manhole
Since 2011, we have reviewed and modified our existing working procedure in the procedures of cleaning petrol interceptor for advancement and a step forwards to facilitate a better safety standard and to better protect our workmen from any forms of injury.

Working steps and procedures of cleaning a petrol interceptor include the opening of the manhole (interceptor cover). Usually, each petrol interceptor contains more than one manhole. In the past, it has been generally accepted that the workmen can first lift up all three manholes at the same time before they start to insert the hoses into the interceptor for cleaning. Due to the fact that no past incidence and/ or injury has been taken place, this routine step was generally adopted for time saving and as a more convenient task.

Before the amendment of the safety regulation,
all manholes were opened at once
However, the opening of more than one manhole at the same time will pose the risk of dropping of equipment as well as stumbling of workmen into the hole. Therefore, we have modified our work procedures to strictly prohibit the opening of more than one manhole prior to the cleaning task. In such, workmen have to follow the orders of opening the first manhole and closing it after completing the cleaning work, then to open the second manhole and repeat the job again.

Through this upgrade of the safety regulation, the injury rate and near-miss incidents that were to happen in the past can be effectively reduced. The safety awareness of the workmen can also be raised.





Reason of treating and recycling waste batteries

Waste battery has been one of the major waste problems encountered by many cities around the world; Hong Kong is of no exception. The chemicals found within the battery will not only harm the environment but is also affecting our health. With our increasing materialized desires and the increasing usage and demand of electronic appliances, more waste batteries have been generated. Improper and irresponsible discarding of waste battery together with household waste will cause adverse impacts to the ecosystem since batteries contain hazardous chemical substances such as cadmium, lead, mercury, nickel, which are all heavy metals.

In the case of Hong Kong, if these waste batteries are disposed along with our municipal waste, these wastes will be disposed in the three strategic landfills, and increasing the toxicity levels of the landfills due to the release of heavy metals. These heavy metals will pollute the underground soil and water table and once entered the food chain, bioaccumulation and biomagnifications will occur, which will directly affect out health.

Providing treatment to used batteries can minimize and eliminate the pollution generated by the leakage of heavy metals. In addition, metals contained in the waste batteries are recyclable resources that can be extracted again and reuse in other areas. Recycling the usable materials to the best possible extent can also reduce the burden to the landfill. Any electrolyte generated from the process should be treated as chemical wastes and proper neutralization, treatment before further discharge according to Hong Kong Environmental Protection Department’s requirement should be ensured.

Normal waste battery treatment in Dunwell includes steps of prescreening, refurbishment, dismantling, recycling and disposal. Handling these waste batteries requires special attention to prevent these hazardous chemicals from both leakages to the environment and health risk to our staffs. Such procedures include inspection of residual charges to prevent electric shocks, spill control of electrolytes and electrodes during transportation and dismantling.
The used batteries will be dissembled and separated into metal, plastic, and electrolyte and then sent to recycling points respectively. All handling processes are conducted in an environmental sound and safe manner, in lines with the Hong Kong Environmental Protection Department’s Waste Disposal Ordinance and the requirements under the international Basel Convention.