39results about How to "Fast decontamination" patented technology

The invention relates to decontamination equipment for automobile parts, in particular to decontamination equipment for unmanned automobile parts. The technical problem to be solved is to provide the decontamination equipment which is used for the unmanned automobile parts and is thorough in decontamination, high in decontamination speed and convenient to operate. In order to solve the technical problem, the decontamination equipment for the unmanned automobile parts is provided. The decontamination equipment for the unmanned automobile parts comprises a bottom plate, a first support, a waste water frame, a second support, a first one-way valve, a first water pipe, a cylinder body, a second water pipe, a second one-way valve, a piston, a connecting rod and the like. A left frame is welded to the leftmost side of the top of the bottom plate. The left side of the top of the bottom plate is connected with the cylinder body in a bolt connection manner. The second water pipe is connected to the lower portion of the left side of the cylinder body in a flange connection manner. By the adoption of the decontamination equipment for the unmanned automobile parts, the effects that decontamination is thorough, the decontamination speed is high, and operation is convenient are achieved, the machine maintenance time can be shortened, a great amount of manpower can be saved, and the decontamination effect is good.

The invention provides a special automobile set for bathing. The special automobile set for bathing comprises a first automobile, a second automobile, a central control system, a monitoring / alarm system, a drying system, an air bathing filtering system, a communication system, a field camera shooting and lighting system, an air conditioner system, a power supply system, a bathing system and a sewage collecting system. By the adoption of the structural mode that the two automobiles fall into one group, the special automobile set for bathing is mainly used for quick washing-disinfection of people affected by nuclear, biological and chemical contamination, and the special automobile set is divided into an air bathing area, a take-off area, a bathing area, a drying / checking area and a dressing area according to the washing-disinfection program, specifically, the first automobile is mainly used for air bathing, taking off, drying / checking and dressing for people, the second automobile is mainly used for providing hot bathing water, and affected people can take a bath in the second automobile. The integrated design is adopted by the special automobile set for bathing, the operation amount is large, the folding and unfolding speed is high, the degree of automation and the degree of informationization are high, and the environmental adaptability is high.

The invention relates to a decontamination solution for processing solid radioactive pollution materials, and aims at solving the problems in the existing electrochemical decontamination electrolyte of radioactive polluted stainless steel is not applicable, and cannot relatively well give consideration of the decontamination effect and treatment of decontamination liquid waste. The invention provides an electrochemical decontamination electrolyte. The electrochemical decontamination electrolyte comprises the following components: 0.25-0.5mol / L of nitric acid, 5-10g / L of oxalic acid and 1-10g / L of citric acid. The electrochemical decontamination electrolyte disclosed by the invention has a good decontamination effect on radioactive pollution stainless steel, and is high in decontamination speed; various components are compatible to a radioactive liquid waste treatment system; the decontamination liquid waste is low in quantity and easy to process; the electrolyte can be recycled, and is small in environmental pollution; and the decontamination effect and the treatment of the decontamination liquid waste are well taken into account.

The invention discloses a biological multienzyme cleaning agent which is characterized by comprising the following raw materials in parts by weight: 15.5-94 parts of deionized water, 1-10 parts of citric acid, 1-20 parts of propylene glycol, 1-10 parts of sodium hydroxide, 1-10 parts of protease, 0.1-6 parts of amylase, 0.1-4 parts of lipase and 0.1-4 parts of cellulase. According to the biological multienzyme cleaning agent, the problem of the conventional multienzyme cleaning agent that enzymes have high possibility of inactivation and hydrolysis is solved; a stable environment is provided, so that the multiple enzymes can coexist in the environment in long term; the validity period of the biological multienzyme cleaning agent can be kept; meanwhile, the decomposition rate of the multiple enzymes cannot be reduced.

The invention provides environment-friendly purification washing paste and a preparation method thereof. The washing paste comprises the following raw materials in parts by weight: 10 to 25 parts of sodium alpha-sulfo fatty acid methyl ester, 1 to 3 parts of sodium crylic acid-maleic anhydride copolymer, 0.5 to 2 parts of sodium carboxymethylcellulose, 8 to 20 parts of sodium citrate, 20 to 35 parts of bentonite, 1 to 3 parts of sodium perborate, 15 to 28 parts of amylase, 6 to 18 parts of coconut diethanolamide, 5 to 15 parts of sodium polyacrylate, 2.5 to 6.5 parts of sodium citrate, 0.1 to 0.4 part of methylparaben, 0.15 to 0.45 part of ethylenediamine tetraacetic acid, 0.2 to 0.45 part of triethanolamine, 0.1 to 0.4 part of beef tallow and 0.05 to 0.2 part of essence. The washing paste is wide in application range, high in decontamination speed and good in effect.

The invention belongs to the fields of sewage treatment and porous conducting materials, particularly discloses an activated carbon washing-resisting electrode and a preparation method and application thereof. The activated carbon washing-resisting electrode comprises a foamed nickel matrix, wherein activated carbon mixing material is attached to and filled in the surface and the holes of the foamed nickel matrix; the activated carbon mixing material comprises activated carbon, acetylene black, polytetrafluoroethylene and carboxymethylcellulose which have the mass ratio of 3-7:0.5-1.5:2-6.5:0.01-0.25; the preparation method of the activated carbon washing-resisting electrode comprises steps of preparing materials, adding carboxymethylcellulose, adding polytetrafluoroethylene, tabletting, and the like; and the application method of the activated carbon washing-resisting electrode for purifying sewage comprises steps of preparing a flow-through capacitor, connecting power supply, purifying sewage, and the like. The invention has the advantages of simple manufacture, economy, durability, good washing-resisting performance, quick pollution cleaning speed, and the like.

The invention discloses a rapid and efficient decontaminating agent for leather sofas. The rapid and efficient decontaminating agent is prepared from, by weight, 18-24 parts of N-oleoyl-N-methyltaurine, 15-20 parts of cocoyl glutamic acid glutamic acid salt, 6-12 parts of polyepoxysuccinic acid, 10-15 parts of ethoxy myristic acid imidazoline, 5-10 parts of tallow diethylol amine oxide, 12-17 parts of anhydrous sodium pyrophosphate, 4-8 parts of polyoxyethylene sorbide monooleate, 14-18 parts of sodium diethylhexyl sulfosuccinate, 5-8 parts of polyvinylpyrrolidone, 7-13 parts of sodium silicate and 80-100 parts of water. The decontaminating agent is remarkable in decontaminating effect, stable in performance, high in decontaminating capacity, high in decontaminating speed, capable of rapidly removing dirt, oil stains and other pollutant on leather of sofas, free of corrosion to leather, safe and environmentally friendly.

The invention provides a detergent for surface of a titanium plate. The detergent comprises the following components by weight percentage: 0.5-1.0% of hydrofluoric acid content, 2.0-5.0% of nitric acid and 94-97.5% of water. The detergent for surface of the titanium plate has the beneficial effects that the decontamination speed is fast, the pollution surface will not be enlarged, and the spots can be thoroughly removed.

The invention relates to novel bridge maintenance equipment which comprises a frame body and fouling cleaning devices mounted on the left side and the right side of the frame body respectively in a symmetric manner; sliding cavities are arranged on the two sides of the frame body respectively in a symmetric manner; each of the fouling cleaning devices comprises a sliding frame mounted in the corresponding sliding cavity in a sliding manner and a rotating frame rotatably mounted at the upper end of the corresponding sliding frame through a rotating shaft; a sliding part is arranged at the bottom of each of the sliding frames; each of the sliding parts comprises a sliding wheel and a sliding rail; a mounting groove is formed in each of the sliding frames; a first driving machine is fixedly mounted on the side wall in each of the mounting grooves; a toothed wheel is fixedly mounted on the force transmission shaft of each of the first driving machines; a toothed rack connected with each of the toothed wheels in a matched manner is fixedly mounted on the outer circle of the corresponding rotating frame; a sliding groove, of which the opening directly faces a sewage pipe, is formed in each of the rotating frames; an ejector rod extending toward the sewage pipe is mounted in each of the sliding grooves in a sliding manner; a spiral hole, of which the opening is away from the sewage pipe, is formed in each of the ejector rods; a first spiral shaft is mounted in each of the spiral holes in a screw thread fit manner; each of the spiral shafts is connected with a second driving machine fixedly mounted the corresponding rotating frame.

The invention discloses a detergent for fishing net. The detergent is made from the following components: a mixture of polyethylene glycol and glycerin, L-aspartic acid, dimethicone, sodium citrate, nanometer active carbon, alpha-terpineol, chlorophyll, vinegar, auxiliary agents, calcium hydrogen phosphate, and water. The detergent is green and causes no pollution. Through the addition of processed nanometer active carbon, chlorophyll, auxiliary agents and vinegar, the dirt removal effect is greatly improved, the dirt removal speed is increased, and the ability in absorption and dissolution of pollutants is obviously improved. Meanwhile, the detergent causes no damage to the fishing net. The components match each other, the cleanliness of the fishing net processed by the detergent can be recovered more than 95% of the original cleanliness, and the brightness can be recovered more than 90%.

The invention discloses a cleaning agent for a laser holographic mould pressing plate. The cleaning agent is characterized by comprising the following components in parts by weight: 2-5 parts of nonionic surfactant, 8-10 parts of dimeric surfactant, 2-5 parts of solubilizer, 3-4 parts of auxiliaries, 0.4-0.6 part of de-foaming agent, 0.4-0.6 part of sodium ethylene diamine tetracetate and 75-85 parts of deionized water; the nonionic surfactant comprises octaphenyl polyoxyethyiene and fatty alcohol-polyoxyethylene ether at mass ratio of 3:2; the solubilizer comprises ethylene glycol butyl etherand propylene glycol at mass ratio of 1:4. The technical scheme of the invention especially designs a novel water-soluble cleaning agent, in order to solve the problems of high difficulty in cleaning, incomplete cleaning, easiness in causing nickel plate darkening, and the like, of the laser holographic mould pressing plate at present; the cleaning agent is capable of protecting the microstructure on the nickel plate as far as possible while increasing the cleaning efficiency.

The invention provides a hand-wash laundry detergent capable of achieving rinsing easily and a preparation method thereof, and belongs to the field of daily chemical products. The hand-wash laundry detergent is prepared from, by mass, 10%-15% of an anionic surfactant, 4%-8% of a foaming agent, 3%-6% of a nonionic surfactant, 3%-6% of a thickener, 0.1%-0.5% of a preservative, 0.1%-0.5% of a compounding ingredient, 3%-6% of potassium laurate, 3%-8% of potassium oleate, 0.1%-0.5% of citric acid, 1.5%-3% of sodium chloride, 0.15%-0.45% of essence and 46.05%-72.05% of water. Compared with the prior art, by means of the low-foaming property of the hand-wash laundry detergent, when the hand-wash laundry detergent is used for machine washing, foam is not likely to be spilled out; meanwhile, the hand-wash laundry detergent has the advantages of being good in resistance to hard water, high in decontamination speed, good in decontamination effect and capable of saving time and labor, and therefore the hand-wash laundry detergent has the good economic benefit and social benefit.

The invention relates to a multifunctional decontamination polishing agent, in particular to a formula and a preparation method of a water-in-oil type multipurpose high-performance decontamination polishing agent. The multifunctional decontamination polishing agent is characterized by consisting of the following components in percentage by weight: 35 to 65 percent of silicon oil, 4.5 to 10 percentof methyl methacrylate, 0.5 to 1.5 percent of dibutyl phthalate, 4 to 7 percent of alkyphenol polyethenoxy ether, 1.5 to 3 percent of triethanolamine, 0.1 to 1 percent of bismuth oxychloride, 0.1 to1 percent of ammonium persulphate, and 15 to 20 percent of 20-percent potassium nitrate solution. The preparation process comprises the step of adding all components in a homogenizer at a rotary velocity of 10,000 to 15,000 rev / m for even mixing to obtain the finished product. The finished product of the invention has the advantages of high decontamination speed, water resistance, polishing protection, and multifunctional one-time completion.

The invention relates to a dry cleaning wiper. The dry cleaning wiper is characterized in that the dry cleaning wiper comprises lanolin alcohol, deionized water, solvent oil, propanetriol, stearic acid, trolamine, polyethylene glycol (80) lauric acid ester, zinc stearate, mineral oil, and the like. The dry cleaning wiper has the main characteristics that: (1), the dry cleaning wiper is operated under an anhydrous condition, and water resources are not wasted; (2), the decontamination speed is high, and the effect is obvious; (3), the dry cleaning wiper has strong applicability, can remove aqueous oil stain and also can remove unctuous oil stain; and (4), the dry cleaning wiper has no toxicity and no public nuisance, and does not cause pollution to the environment.

The invention discloses a quick-acting glass washing agent and a method for preparing the same. The quick-acting glass washing agent comprises, by weight, 6-11 parts of propoxylation octadecyl benzoate, 8-14 parts of fatty acid methyl ester ethoxylate sulfonate, 5-10 parts of polyethylene glycol octylphenol ether, 7-13 parts of polyoxyethylene lauryl ether disodium stearamido mea-sulfosuccinate, 4-8 parts of ethyl hexanol polypropylene oxide polyoxyethylene ether, 3-6 parts of rhamnolipid, 4-8 parts of dodecyl benzenesulfonic acid triethanolamine salt, 5-10 parts of sodium cumenesulfonate and 100-120 parts of water. The quick-acting glass washing agent and the method have the advantages that dirt attached onto glass can be quickly removed under the effects of surfactants such as the propoxylation octadecyl benzoate, the fatty acid methyl ester ethoxylate sulfonate and the polyoxyethylene lauryl ether disodium stearamido mea-sulfosuccinate, good washing effects can be realized, the quick-acting glass washing agent is high in dirt removal speed and efficiency and is environmentally friendly, and the time can be saved to a great extent.

The invention discloses an oil filter for eliminating a lubricating oil film. The oil filter comprises an oil inlet pipeline, an oil outlet pipeline and an oil pump arranged on the oil inlet pipeline,and further comprises an electrical control device which is electrically connected with the oil pump, wherein a first prefilter, a charging mixer, a second prefilter, an exchange resin filtering unitand a protection filter are sequentially arranged between the oil inlet pipeline and the oil outlet pipeline; pressure sensors are arranged on the first prefilter, the second prefilter, the exchangeresin filtering unit and the protection filter; and the electrical control device is electrically connected with the pressure sensors. The oil filter disclosed by the invention has the performance ofpeeling and cleaning the oil sludge / film in the system and is safe; and moreover, the sampling pollution degree at any part of the whole system after purification is less than or equal to NAS 5 level,and the membrane propensity score (MPC) is less than 10.

The invention relates to a cleaning agent of which the formula basically comprises the following components in percentage by weight: 20-30% of nonylphenol polyethenoxy ether, 10-20% of tetrachloroethylene, 30-40% of dichloromethane and 15-25% of kerosene. Compared with the prior art, the cleaning agent adopts the formula comprising the components of nonylphenol polyethenoxy ether, tetrachloroethylene, dichloromethane and kerosene, and has the following advantages: the cleaning agent has powerful solubility and can quickly dissolve oil stain of carbon, vegetable oil and petroleum products, so that the stain can be erased by gently wiping with cloth or washed away by washing with water, thereby achieving the effects of high stain removal speed and complete and thorough stain removal; and the cleaning agent only powerfully dissolves the stain and is non-corrosive to a metal part, thereby avoiding the chemical reaction with metal materials. Thus, the cleaning agent is a product which is safe to use and good in cleaning effect.

The invention relates to the technical field of pilotless equipment, in particular to pilotless automobile surface decontamination equipment, and aims at achieving the technical purpose of providing pilotless automobile surface decontamination equipment which is simple in structure and high in decontamination capability and decontamination speed. In order to achieve the technical purpose, the pilotless automobile surface decontamination equipment comprises wheels, a water pump, a water tank, an electronic control valve, a water inlet, a sliding block, a sliding rail, a first fixing plate, a water pipe, an electric pushing rod, a rotating motor, a second fixing plate and the like; the wheels are connected to the bottom of a bottom plate through bearings and can freely rotate, and the water tank is connected at the left side of the top of the bottom plate through bolts. According to the pilotless automobile surface decontamination equipment, the effects of being simple in structure and high in decontamination capability and decontamination speed are achieved, a worker can conduct quick decontamination operation on the surface of a pilotless automobile through the equipment, and operation is easy.

The invention belongs to the fields of sewage treatment and porous conducting materials, particularly discloses an activated carbon washing-resisting electrode and a preparation method and application thereof. The activated carbon washing-resisting electrode comprises a foamed nickel matrix, wherein activated carbon mixing material is attached to and filled in the surface and the holes of the foamed nickel matrix; the activated carbon mixing material comprises activated carbon, acetylene black, polytetrafluoroethylene and carboxymethylcellulose which have the mass ratio of 3-7:0.5-1.5:2-6.5:0.01-0.25; the preparation method of the activated carbon washing-resisting electrode comprises steps of preparing materials, adding carboxymethylcellulose, adding polytetrafluoroethylene, tabletting, and the like; and the application method of the activated carbon washing-resisting electrode for purifying sewage comprises steps of preparing a flow-through capacitor, connecting power supply, purifying sewage, and the like. The invention has the advantages of simple manufacture, economy, durability, good washing-resisting performance, quick pollution cleaning speed, and the like.

A kind of bridge maintenance equipment, comprising a frame body and decontamination devices installed on the left and right sides of the frame body. The rotating shaft is rotatably installed on the rotating frame at the upper end of the sliding frame, and a mounting groove is also arranged in the sliding frame, and a first driving machine is fixedly installed in the side wall of the mounting groove, and a gear is fixedly mounted on the power transmission shaft of the first driving machine. The outer circle of the rotating frame is fixed with a toothed bar that is connected with the toothed wheel. The rotating frame is provided with a sliding groove with the port facing the sewage pipe, and a push rod extending toward the sewage pipe is installed in the sliding groove. The rod is provided with a screw hole whose port is far away from the sewage pipe, and the spiral pattern in the screw hole is matched with a first screw shaft, which is connected with the second driving machine fixedly installed in the rotating frame, and the rotating frame faces the end surface of the sewage pipe An elastic decontamination arm for extending into the sewage pipe and for decontamination is arranged mutually symmetrically up and down.

The invention discloses an energy-saving and environment-friendly air purification tower for poplar catkin filtration, which comprises a cubic tower body. The inner side of the tower body is a double-layer water storage tank, a multi-stage filter mechanism, a fan, Ring-shaped bag type dust collector, the top of the tower body is provided with air outlet louvers, the two groups of opposite sides of the tower body are provided with air inlets, and the multi-stage filter mechanism is arranged in the air inlet channel of the air inlet Above, the air inlet is provided with an air inlet filter mechanism, and the side of the tower body is provided with a foldable poplar catkin attachment plate, and the foldable poplar catkin attachment plate is connected with the side of the tower body or the air inlet filter mechanism. The present invention can unfold the foldable catkin attachment plate, and attach the catkins through the foldable catkin attachment plate, so as to reduce the poplar catkins in the air, and the poplar catkin attachment net of the foldable catkin attachment plate is driven by the attachment net driving roller. Rotate and scrape off the catkins with the scraper, and the catkins will accumulate on one side of the scraper.

The invention relates to a decontamination solution for processing solid radioactive pollution materials, and aims at solving the problems in the existing electrochemical decontamination electrolyte of radioactive polluted stainless steel is not applicable, and cannot relatively well give consideration of the decontamination effect and treatment of decontamination liquid waste. The invention provides an electrochemical decontamination electrolyte. The electrochemical decontamination electrolyte comprises the following components: 0.25-0.5mol / L of nitric acid, 5-10g / L of oxalic acid and 1-10g / L of citric acid. The electrochemical decontamination electrolyte disclosed by the invention has a good decontamination effect on radioactive pollution stainless steel, and is high in decontamination speed; various components are compatible to a radioactive liquid waste treatment system; the decontamination liquid waste is low in quantity and easy to process; the electrolyte can be recycled, and is small in environmental pollution; and the decontamination effect and the treatment of the decontamination liquid waste are well taken into account.

The invention provides a special automobile set for bathing. The special automobile set for bathing comprises a first automobile, a second automobile, a central control system, a monitoring / alarm system, a drying system, an air bathing filtering system, a communication system, a field camera shooting and lighting system, an air conditioner system, a power supply system, a bathing system and a sewage collecting system. By the adoption of the structural mode that the two automobiles fall into one group, the special automobile set for bathing is mainly used for quick washing-disinfection of people affected by nuclear, biological and chemical contamination, and the special automobile set is divided into an air bathing area, a take-off area, a bathing area, a drying / checking area and a dressing area according to the washing-disinfection program, specifically, the first automobile is mainly used for air bathing, taking off, drying / checking and dressing for people, the second automobile is mainly used for providing hot bathing water, and affected people can take a bath in the second automobile. The integrated design is adopted by the special automobile set for bathing, the operation amount is large, the folding and unfolding speed is high, the degree of automation and the degree of informationization are high, and the environmental adaptability is high.

The invention relates to an industrial fishpond water surface sewage cleaning machine which comprises a fixed rod, a movable rod, foam plates, magnets, suction heads, a self-sucking pump and sewage-sucking pipes, wherein one ends of the fixed rod and the movable rod are connected to the fixed foam plate, and the other ends are respectively connected with the two movable foam plates; the small magnets are respectively laid in the two movable foam plates; drop stones are arranged below the foam plates; the suction heads are arranged above the fixed rod and the movable rod and connected with thesewage-sucking rigid pipe; the self-sucking pump is arranged on a flat car outside a pond and connected with the sewage-sucking flexible pipe and a sewage discharge pipe, the sewage-sucking flexible pipe is connected to the sewage-sucking rigid pipe and connected outside the pond after penetrating through the sewage discharge pipe from the suction heads. The cleaning machine can effectively eliminate the sewage at the water surface of the industrial fishpond, has low cost, simple and convenient operation and removal efficiency of more than 93 percent, achieves the aims of controlling and improving the water quality of the culture pond, is an industrial fish culture special device and is suitable for industrial culture production at a large scale.

Disclosed is improved bridge maintenance equipment. The improved bridge maintenance equipment includes a frame body and decontamination devices symmetrically mounted on the left and right sides of theframe body. Sliding cavities are formed in the two sides of the frame body symmetrically. Each decontamination device includes a sliding frame mounted in the corresponding sliding cavity in a slidingmode and a rotating frame mounted at the upper end of the sliding frame rotatably. Mounting grooves are further formed in the sliding frames. A first driving machine is fixedly mounted in the side wall of each mounting groove. A force transmitting shaft of each first driving machine is fixedly provided with a tooth wheel. A tooth strip connected with the corresponding tooth wheel in a matched mode is fixedly mounted on the outer circle of the corresponding rotating frame. A sliding groove with an end opening facing a sewage pipe is formed in each rotating frame. An ejector rod extending towards the sewage pipe is mounted in each sliding groove in a sliding mode. A spiral hole with an end opening away from the sewage pipe is formed in each ejector pipe. A first spiral shaft is mounted in each spiral hole in threaded and matched modes. Each first spiral shaft is connected with a second driving machine fixedly mounted in the corresponding rotating frame. Elastic decontamination arms usedfor stretching into the sewage pipe for decontamination are arranged on the end surfaces, facing the sewage pipe, of the rotating frames in a vertical symmetrical mode.

The invention relates to a sewage filtering apparatus. A water inlet of a water pump is connected with a screen, a water outlet of the water pump is connected with a groove at an upper part of a quartz sand container, several blind holes are arranged at a lower part of the groove; and a diameter of mesh holes of an external layer filter screen is larger than the mesh holes of an internal layer filter screen. The double layer filter screens of the screen have characteristic for absorbing large suspended matters, the quartz sand container containing several blind holes can realize rapid contact of quartz sand and sewage, and small suspended matters in sewage can be rapidly filtered and removed. The sewage filtering apparatus has the advantages of fast sewage processing speed and low cost, and is suitable for large scale usage.

The invention relates to a method for realizing quick reduction of contaminants in domestic sewage, in particular to a method for realizing quick reduction of contaminants in domestic sewage within a short time based on variable pressure gradient, in order to solve the problem that the existing biological method needs long time for treating the domestic sewage and slow in taking effect. The method includes: taking domesticated aerobic activated sludge to be mixed with the sewage, pouring the mixture into a high pressure reactor, supplying oxygen to the high pressure reactor via an air compressor, adjusting opening degree of a high pressure reactor exhaust valve by taking 0.1MPa as an adjustment unit so as to control aeration pressure in the reactor to be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 and 0.7MPa sequentially, operating the reactor under variable pressure on the seven-gradient pressure conditions, operating the reactor under each pressure state for 15minutes, relieving pressure after one operation cycle is finished, discharging the sludge from a water outlet, and continuing to use the reactor at a next operation cycle. The method can realize quick reduction of target contaminants in the domestic sewage within short time and is applied to the field of sewage treatment.