Which types of projects can use an MEMIOS automated waste management system?

MEMIOS provides automated waste collection systems for any number of applications. Each system is designed to accommodate the specific development waste production needs. The MEMIOS solutions are direct replacement for older traditional waste management methods and can service any development project with considerable economic, environmental and time savings over conventional methods.

Can I use an MEMIOS automated waste management system on our existing campus or buildings?

MEMIOS is the only pneumatic waste transport and collection system provider that has designed and developed a specific line of solutions for retrofit projects of all sizes.

Is there a maximum capacity for a given project size?

The important point to highlight for a given project size is a function of the anticipated volume of waste moving through the primary transport pipe. Because the MEMIOS systems can be programmed to move waste as it is deposited much higher throughput volumes can be achieved. Other control options allow for waste to be transported based on calendar times. Depending on the waste removal strategy and overall pipe distances the MEMIOS systems can move anywhere from one ton up to 10 tons per hour. These results may also change depending waste stream segregation desires and waste management goals for the project over time.

Which types of waste can be collected with an MEMIOS system?

Any waste collected by or on the order of municipalities falls under the definition of what a MEMIOS system can transport through its system. According to the Organization for Economic Co-operation and Development (OECD), municipal waste is "waste from households, including bulky waste, similar waste from commerce and trade, office buildings, institutions and small businesses, yard and garden waste, street sweepings, the contents of litter containers, and market cleansing waste." All MSW waste such as papers, plastics, cans, glass etc can be deposited and transported by the MEMIOS system. Typically standard household and commercial/residential waste can be conveyed through the system.

Which types of waste cannot be conveyed in a MEMIOS system?

Large furniture, appliances, heavy metal objects, dangerous or illegal chemicals or liquids.

Where should the central waste collection area be located?

There are many factors to consider before choosing the central collection area. Knowing the long-term waste goal is a significant aspect to consider along with understanding all the trade-offs that can affect the CAPEX and OPEX costs over the life of the project. A good rule of thumb to consider however, is that the more central the collection area is to the entire project, the more "balanced" the pipe network can be and therefore the lower the operational costs will end up being.

What volume size waste containers can be attached to the MEMIOS system?

Compaction haul-off containers are typically sized based on the maximum road weight limits allowed for the hauler. There are many types and sizes of waste containers and they vary based on truck lift and removal devices, space limitations and the waste collection volumes. Container sizes can range anywhere from 5 cubic yards up to 40 cubic yards in capacity. Custom containers can also be provided based on specific client needs.

What is the compaction ratio of the containers?

This may vary but typical is a 4:1 ratio depending on Waste makeup.

What size space or facility will our project need for the central collection area?

The size of central collection area will vary depending on the waste volumes and the number of waste streams desired and whether sustainability is a part of the solution. Depending on hauler round trip run times number of containers (back up containers included) along with hauler site frequency will all determine required area sizes. Additional issues that will influence size are architectural limitations, real estate costs, locations and ingress and egress options. he collection terminals can be designed in several floors. They can also be entirely above ground, entirely underground and semi-underground/over ground.

Can glass and other erosive waste be thrown in an MEMIOS system?

Yes it can if it's mixed up with other waste. MEMIOS has developed a calculation tool that calculates the needed thickness of the pipe to secure a minimum life of 30 years. One of the parameters in this calculation is the percent of erosive waste that will be thrown in the system. The percent of glass or other erosive material should not exceed 10% of the total weight of the waste collected. Larger quantities of pure glass or other erosive material would require a thickness of the pipe that is impossible to make.

Which material are the pipes made of?

Generally, the straight pipes are made of carbon steel at different thicknesses depending upon the expected waste loads and their erosion properties. The bends are especially sensitive and therefore often made of Boron steel. The expected erosion factor is the most critical factors for the design of an installation. MEMIOS has, due to our experience from over 600 installations, 40 years of operation and maintenance extensive experience and knowledge in this field.

Do the streets have to be opened to repair a broken pipe?

Usually not in a 500 mm pipe system, the majority of the repair can be done from inside of the pipe by fitting (welding) small plates to the holes. Internal pipe repair can be done in less than 1 day. If a 400 mm pipe system is installed then the repair has to be done externally, i.e. opening the trenches.

Can the pipes be installed hanging?

Yes, they can. If special requirements have to be met, customary design is made to fulfil these conditions. The pipes are protected with a PE-coating which is normally enough for the installation in trenches. In the case of bends other types of external coatings can be also used, but always according to international standards. Corrosion of the pipes may appear if they are installed in corrosive environments. In these cases we install anode or cathode protection. This gives sufficient protection and is considerably less expensive than using stainless steel pipes.

Is it necessary to clean the pipe system?

No, usually not. The waste cleans the pipes sufficiently for most applications. If wet and very sticky waste should be transported a cleaning buoy should be used periodically. Please contact the Service department at nearest MEMIOS office for more information.

What is the air speed of the waste transport in the pipes?

Depending on the density of the waste and the transportation distance it varies between 20 and 25 m/s.

Can the pipes be installed below the water table?

Yes, the pipes that MEMIOS use are prepared to be installed directly in the ground independently of whether they are below the water table or not. The pipes have a special external protection: a 3 layers polyethylene coating. We are using exactly the same protection as the gas pipes, in accordance with European standards, when the pipe is installed in the ground. We have a number of installations where the pipe is located below the water table. Some of these installations were built more that 20 years ago and are still in very good condition.

Can the pipes be installed directly into the water?

Yes, they can. We have several installations where the pipe is directly installed in the water. One installation is the Lisbon Waterfront (see picture below).

What about installing an MEMIOS system in an earth quake zone?

In this case we need to consult local expertise. We have some experience from the Taipei Financial Centre project in Taiwan.

What about ground settlements?

Yes, an MEMIOS system can be installed in settling grounds, but special provisions have to be made.

How should frost in ground be handled?

We have a lot of experience with frost in ground through our Scandinavian installations, so please contact your local MEMIOS sales or technical department for advice.

What about flooding areas?

See above installing the pipe under the water table and in water. If an MEMIOS system should be installed in an area which is exposed to flooding risks special provisions should be made in order to stabilize the pipes.

Do the inlets need cleaning?

The standard MEMIOS waste inlets do not need to be cleaned on the inside. The outdoor inlets, usually has to be cleaned or re-painted on the outside due to weather, stains from waste and or graffiti.

How many dwellings can be supported by one inlet point?

One inlet point is a point next inside or outside a house which hosts one or several inlets dedicated to serve that building or adjacent buildings. The number of households connected to one storage point is dependent on their expected waste volume, walking distance, storage capacity in the inlet and size of the system. Typically, 40-80 households are allocated to each inlet point. If there is a need for more this can be solved by expanded storage techniques.

How big waste bags can be thrown in an MEMIOS system?

The maximum size of the waste bag depends on the pipe diameter used in the system. But, in 500 systems, usually bags from residential areas 10-30 litres and from commercial up to 120 litters can be thrown in to the system.

How should one prevent children from entering into the inlet?

A 300 mm opening is not generally recommended for residential areas with unlimited access for all type of users. The inlet door should be positioned at minimum 1100mm above ground. For larger inlet doors (often needed for retail or commercial users) an access control is needed (manual lock or others).

Do the chutes need to be ventilated?

All inside valve/tank rooms should be ventilated, both outdoor and indoor.

Which is the recommended maximum height for the chute in high-rise buildings?

Typically 50 floors - higher buildings need special solutions.

How does MEMIOS handle multiple fractions in high-rise buildings?

Separate chutes, or separate outdoor inlets for the less frequent waste streams. In certain cases also a specially developed "revolver solution" can be applied, where one chute is applied handling two to four separate waste streams. For more information about its applicability, please contact your MEMIOS office.

How deep are the pipes buried?

The pipes are generally buried between 1-1.5 m below street level. If there are valves in the street, the depth is normally between 1.5 m-2.5 m

In what lengths are the pipes delivered?

6 or 12 m (straight pipes).

What is the maximum elevation of a pipe?

It is normally recommended not to exceed 20°, both downhill and uphill. There is always a risk that not all waste will be taken away by the air stream if the inclination is larger than 20°. Waste residuals in the pipes may then cause blockages, which have to be cleared.

Can the system be installed in existing buildings?

Yes, it can and often is! Many of our installations are done in so called consolidated areas (city centres), where the adjacent buildings are either directly or indirectly connected. The easiest way is often to install outdoor waste inlets, but also indoor inlets can be used. If the buildings have waste chutes it may be worthwhile to study if it is possible to connect existing chutes to the pipe system.

Can pipes be installed in conjunction with other underground installation works?

Yes, it can and it often makes sense to combine the installation of an MEMIOS system when the streets are opened anyway.

When the first high-rise MEMIOS system was built and where are high-rise systems?

The first high rise system (>20 storeys) was installed in Fanling, Hong Kong 1995-96. It covers 6 building with 4000 dwellings. A majority of the high rise systems MEMIOS has installed are in Asia (e.g. Hong Kong 7 systems with up to 40 floors, Singapore 1 with approx. 70 floor. In Taipei in Taiwan MEMIOS has installed one system in the Taipei 101 Financial Tower with 101 floors).

How are the pipes installed in high-rise buildings?

Same as other systems, both below ground and suspended. However, special consideration should be taken to the valve rooms to allow absorption of gravity forces from waste bags falling from higher floors.

How is source separation best achieved in high-rise buildings?

We recommend installing multiple chutes. If a "revolver" type system (using only one chute for several fractions) is considered a simulation of the disposal capacity of the system should be done. MEMIOS can do such a simulation study as well as provide revolver solutions, if applicable.

How does a power failure affect an MEMIOS system?

As long as the terminal building is not affected by the power failure the system will keep running. The standard MEMIOS system does not require electrical power in the inlets or in the inlet net. Each inlet is just connected to the terminal with a compressed air pipe and an electronic bus. In some cases, our terminals are equipped with double connections or an autonomous electrical generator.

Which guarantees can MEMIOS provide that the installation runs properly in the future?

MEMIOS offers long term service agreements ensuring proper operation of the installation by specially trained and educated MEMIOS staff. When signing a long term service agreement MEMIOS automatically guarantee the smooth operation of the installation over many years.

How usual are blockages and valve failures in the system?

It happens, but it is not a major problem. A severe blockage, which has to be attended manually, appears less than once a year per installation on average. Blockages that can be removed by the operational system happen more frequently (described below), but those do not imply a reduction in the availability of the system. MEMIOS has special equipment for this and our staff is trained to swiftly remove any eventual blockages.

How is a blockage fixed?

90% of the blockages are solved by increasing the air pressure and this can be done with remote control. Other methods to break the blockage, if not resolved by increasing air pressure, are: Using a special buoy In extreme situations it can be necessary to clear the blockage manually