A vacuum truck, vacuum tanker, vactor truck, or vactor is a

tank truck A tank truck, gas truck, fuel truck, or tanker truck (American English) or tanker (British English) is a motor vehicle designed to carry liquids or gases on roads. The largest such vehicles are similar to railroad tank cars, which are also design ...

that has a pump and a tank. The pump is designed to pneumatically suck liquids, sludges,

slurries A slurry is a mixture of denser solids suspended in liquid, usually water. The most common use of slurry is as a means of transporting solids or separating minerals, the liquid being a carrier that is pumped on a device such as a centrifugal pu ...

, or the like from a location (often underground) into the tank of the truck. The objective is to enable transport of the liquid material via road to another location. Vacuum trucks transport the collected material to a treatment or disposal site, for example a

sewage treatment plant Sewage treatment (or domestic wastewater treatment, municipal wastewater treatment) is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable for discharge to the surrounding envir ...

. A common material to be transported is

septage Fecal sludge management (FSM) (or faecal sludge management in British English) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal slud ...

(or more broadly:

fecal sludge Fecal sludge management (FSM) (or faecal sludge management in British English) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal slud ...

) which is

human excreta Human waste (or human excreta) refers to the waste products of the human digestive system, menses, and human metabolism including urine and faeces. As part of a sanitation system that is in place, human waste is collected, transported, treated ...

mixed with water, e.g. from

septic tank A septic tank is an underground chamber made of concrete, fiberglass, or plastic through which domestic wastewater ( sewage) flows for basic sewage treatment. Settling and anaerobic digestion processes reduce solids and organics, but the treatm ...

s and

pit latrine A pit latrine, also known as pit toilet, is a type of toilet that collects human feces in a hole in the ground. Urine and feces enter the pit through a drop hole in the floor, which might be connected to a toilet seat or squatting pan for use ...

s. They also transport

sewage sludge Sewage sludge is the residual, semi-solid material that is produced as a by-product during sewage treatment of industrial or municipal wastewater. The term "septage" also refers to sludge from simple wastewater treatment but is connected to si ...

, industrial liquids, or slurries from

animal waste Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nutrie ...

from livestock facilities with pens. Vacuum trucks can also be used to prepare a site for installation or to access underground utilities. These trucks may use compressed air or water to break up the ground safely, without risk of damage, before installation may begin. Vacuum trucks can be equipped with a high pressure pump if they are used to clean out sewers from sand.

Other names used

Other names used for vacuum trucks: vacuum tanker, "Sucker truck" (in Australia) or "Sewer Sucker", "Hydro-vac", or "vac-trucks" (in Canada) or "Exhauster truck" (in Rwanda, Malawi). Slang terms include: "honey truck", "honey sucker" (in India and South Africa), and " honeywagon", all (probably) derived from honey bucket. When a vacuum truck is used to transport

then it can also be called "fecal sludge truck".

Design and configurations

Commercial vacuum trucks which collect fecal sludge usually have a volume of .Strande, L., Ronteltap, M., Brdjanovic, D. (eds.) (2014)
Faecal Sludge Management (FSM) book – Systems Approach for Implementation and Operation
. p. 81. IWA Publishing, UK () However various smaller versions for specialized applications or low-resource settings can be found with tanks as small as .

Pumps

They generally use a low-volume sliding vane pump or a

liquid ring pump A liquid-ring pump is a rotating positive-displacement gas pump, with liquid under centrifugal force acting as a seal. They are typically used as a vacuum pump, but can also be used as a gas compressor. The function of a liquid-ring pump is si ...

to create a negative air pressure. The use of diaphragm mud pumps is less common, but with the advantage of a simpler design and usually lower overall costs. The disadvantage is that mechanical parts come into contact with the sludge, which is not the case for the more common vacuum pumps. The truck can be configured to be a direct belt drive, or a hydraulic drive system. There are two different ways to mount the pump: either directly on the truck with the vacuum drive powered by the truck motor, or on the trailer with an independent motor. The second option with the independent motor is more complicated and not commonly used. It has the advantage of potentially having the pump closer to the septic tank. It is also able to use the negative pressure

suction Suction is the colloquial term to describe the air pressure differential between areas. Removing air from a space results in a pressure differential. Suction pressure is therefore limited by external air pressure. Even a perfect vacuum canno ...

side of the pump as well as the positive pressure side to pump sludge over longer distances or lift it higher into the tank.

Suction hoses

The suction hoses are typically 2" - 4" (or 50mm to 100mm) in diameter with 3" (or 75mm) being the norm. The possible length depends on various factors mainly related to the lift and other pressure losses. It is usually impossible to extend it beyond . An inherent

limitation of all

suction pump A vacuum pump is a device that draws gas molecules from a sealed volume in order to leave behind a partial vacuum. The job of a vacuum pump is to generate a relative vacuum within a capacity. The first vacuum pump was invented in 1650 by Otto vo ...

s is that they can only lift a liquid through utilizing

atmospheric pressure Atmospheric pressure, also known as barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as , which is equivalent to 1013.25 millibars, ...

. For pure water the theoretical maximum lift is approximately . However, due to the

viscosity The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the inter ...

of fecal sludge it is possible to mix air into it either by sucking close from the surface or by adding air with a

compressor A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor. Compressors are similar to pumps: both increase the pressure on a fluid and both can transp ...

through a separate hose. Through this process, the overall density of the sludge/air mixture can be reduced below that of pure water and thus a higher lift () can be reached under optimal conditions. Other factors affecting the possible lift and total length of the suction hose are that single stage

vacuum pump A vacuum pump is a device that draws gas molecules from a sealed volume in order to leave behind a partial vacuum. The job of a vacuum pump is to generate a relative vacuum within a capacity. The first vacuum pump was invented in 1650 by Otto ...

s only reach an 85-90% partial

vacuum A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often dis ...

, and that small air leakages, pipe

friction loss The term friction loss (or frictional loss) has a number of different meanings, depending on its context. * In fluid flow it is the head loss that occurs in a containment such as a pipe or duct due to the effect of the fluid's viscosity near the ...

es, and the

of the liquid further reduce the possible lift.

Emptying the tanker

Normally a tanker is emptied by gravity. It is possible to pressurize the vacuum tank to "pressure out" the liquid quicker (or against a small difference in elevation). This procedure is detrimental for the equipment, hence is used in special situations. The regular discharge time for a tanker of is about 15 minutes (or 7–10 minutes to unload a tanker of ). The outlet is typically in diameter. The discharge time depends on the thickness of the sludge, the size of the outlet valve and hose, the amount of garbage in the fecal sludge, and the frequency of driver cleaning the dump screen.

Uses

Vacuum trucks are used by town and municipal governments, as well as commercial entities around the world.Strande, L., Ronteltap, M., Brdjanovic, D. (eds.) (2014)
Faecal Sludge Management (FSM) book - Systems Approach for Implementation and Operation
. IWA Publishing, UK ()

Human excreta

Several types of non-centralized sanitation systems are served by vacuum trucks. They are used to empty

from

cesspit A cesspit (or cesspool or soak pit in some contexts) is a term with various meanings: it is used to describe either an underground holding tank (sealed at the bottom) or a soak pit (not sealed at the bottom). It can be used for the temporary co ...

s, and communal

latrine A latrine is a toilet or an even simpler facility that is used as a toilet within a sanitation system. For example, it can be a communal trench in the earth in a camp to be used as emergency sanitation, a hole in the ground ( pit latrine), or ...

s, for street cleanup, for sewer clean out, and for individual

septic system Onsite sewage facilities (OSSF), also called septic systems, are wastewater systems designed to treat and dispose of effluent on the same property that produces the wastewater, in areas not served by public sewage infrastructure. A septic tank a ...

s. The trucks are used in the cleaning of sanitary sewer pumping stations. Vacuum trucks are used to empty

portable toilet A portable or mobile toilet (colloquial terms: thunderbox, portaloo, porta-john or porta-potty) is any type of toilet that can be moved around, some by one person, some by mechanical equipment such as a truck and crane. Most types do not require ...

s. In commercial

aviation Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot air ...

, vacuum trucks are used to collect waste from

airplane An airplane or aeroplane (informally plane) is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, propeller, or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurations. The broad spectr ...

toilets. Vacuum trucks discharge these wastes to the sewer network, to a

wastewater treatment plant Wastewater treatment is a process used to remove contaminants from wastewater and convert it into an effluent that can be returned to the water cycle. Once returned to the water cycle, the effluent creates an acceptable impact on the environmen ...

, or—usually illegally, for example in many developing countries— directly into the environment. The latter practice, called "institutionalised

open defecation Open defecation is the human practice of defecating outdoors ("in the open") rather than into a toilet. People may choose fields, bushes, forests, ditches, streets, canals, or other open spaces for defecation. They do so either because they d ...

", is dangerous since it constitutes a

public health Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals". Analyzing the det ...

and environmental hazard.

Industrial liquids

Vacuum trucks are used in the

petroleum industry The petroleum industry, also known as the oil industry or the oil patch, includes the global processes of exploration, extraction, refining, transportation (often by oil tankers and pipelines), and marketing of petroleum products. The largest ...

, for cleaning of storage tanks and spills. They are also an important part of drilling oil and natural gas

wells Wells most commonly refers to: * Wells, Somerset, a cathedral city in Somerset, England * Well, an excavation or structure created in the ground * Wells (name) Wells may also refer to: Places Canada *Wells, British Columbia England * Wells ( ...

, as they are located at the drilling site. Vacuum trucks are used to remove drilling mud, drilling cuttings, cement, spills, and for removal of

brine Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for b ...

water from production tanks. They dispose of this in sump pits, treatment plants or if within safe levels may be spread in farm fields.

Others

Vacuum trucks are also used for exposing underground utilities. Before installing many pieces of underground equipment, the ground must to be excavated far enough down to create a solid foundation for the structure to be placed on. Underground utilities can include lamp poles, traffic lights, road signs, and even commercial grade trees for landscaping. To prepare the ground for installation it is jetted with water, and the vacuum truck sucks up the muddy product. This exposes the buried utility without the possibility of damage, as would be possible if a digging machine were used (i.e. tractor backhoe, tracked or wheeled excavator, ditch witches). Vacuum trucks can also be used for cleanup of

contaminated soil Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity ...

. For some instances, air excavation many be used in place of hydro excavation. Air excavation, also known as soft dig, uses compressed air to break up the ground and then vacuums up the soil into the debris tank. Air excavation is often used for locating underground electrical cables and gas lines.

Examples

Bangalore, India

A typical vacuum truck in India has a capacity of and serves about five buildings a day. Assuming a 2-year emptying cycle one truck can cater to about 3,000 to 4,000 buildings or 15,000 to 20,000 people. Vacuum trucks are an alternative to the dangerous and humiliating practice of

manual scavenging Manual scavenging is a term used mainly in India for "manually cleaning, carrying, disposing of, or otherwise handling, human excreta in an insanitary latrine or in an open drain or sewer or in a septic tank or a pit". Manual scavengers usually u ...

that became illegal in India with the Manual Scavenging Act of 1993. In the city of

Bangalore Bangalore (), officially Bengaluru (), is the capital and largest city of the Indian state of Karnataka. It has a population of more than and a metropolitan population of around , making it the third most populous city and fifth most ...

alone, it is estimated that there were up to 200 such trucks in 2012, serving more than 3 million people. These vacuum trucks are operated by private companies without the need for subsidies. The charge for emptying a septic tank is between 1,200 and 3,000 Rupees (USD 24 and 60) every two years. After three months of

compost Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical and biological properties. It is commonly prepared by decomposing plant, food waste, recycling organic materials and manure. The resulting m ...

ing, a truckload of compost can be sold for 1,500 to 2,000 Rupees (USD 30 to 40). In the Bangalore area, compost is used primarily on banana and coconut trees. Compost can generate revenues since it replaces expensive fertilizer. If

is discharged on land for composting, each vacuum truck requires of land for composting.

References

External links

Factsheet on motorised emptying and transport
{{DEFAULTSORT:Vacuum Truck Waste collection vehicles Waste management in India Industrial equipment Cleaning tools Trucks Sewerage infrastructure Sanitation