3895 results about "Emission standard" patented technology

In the processes for treating municipal sewage and storm water containing biosolids to discharge standards, biosolids, even after dewatering, contain typically about 80% water bound in the dead cells of the biosolids, which gives biosolids a negative heating value. It can be incinerated only at the expense of purchased fuel. Biosolids are heated to a temperature at which their cell structure is destroyed and, preferably, at which carbon dioxide is split off to lower the oxygen content of the biosolids. The resulting char is not hydrophilic, and it can be efficiently dewatered and/or dried and is a viable renewable fuel. This renewable fuel can be supplemented by also charging conventional biomass (yard and crop waste, etc.) in the same or in parallel facilities. Similarly, non-renewable hydrophilic fuels can be so processed in conjunction with the processing of biosolids to further augment the energy supply.

The invention discloses a sewage treatment unit with good practicality. The sewage treatment unit comprises a settling box, a purifying box and a disinfection box, wherein the top end of one side of the settling box is provided with a chemical reagent tank; the top of the settling box is provided with a stirring motor; a sludge discharge outlet is formed in the bottom end of the settling box; the interior of the purifying box is provided with, from top to bottom, a magnet adsorption screen, a biomembrane filter screen and an active carbon filter screen; the sidewall of the disinfection box is provided with an ozone generator; and gas-distributing pipes are arranged in the disinfection box. The sewage treatment unit provided by the invention can effectively eliminate heavy metals, microbes, organic harmful substances, particulate matters and other impurities in water, is capable of removing pigments and peculiar smell in water, and has improved sewage treatment effect; and since the ozone generator is mounted on the sidewall of the disinfection box, ozone generated by the ozone generator can be used for sterilization and disinfection of purified clear water after purification of sewage, so sewage is allowed to reach discharge standard.

The invention relates to a method for recycling sulfur from acid gases containing hydrogen sulfide, comprising the following steps: (a) air supply; (b) acid gas pretreatment; (c) mixture; (d) primary direct catalytic oxidation; (e) primary sulfur condensation; (f) process gas reheating; (g) secondary direct catalytic oxidation; (h) secondary sulfur condensation; (i) sulfur re-separation; (j) degasification in a liquid sulfur tank; and (k) tail gas burning. When the volume concentration of H2S in the acid gases in the prior art is 1-15%, the recycle rate of sulfur can reach over 99% by the method of the invention, and the emission load of H2S in the acid gases processed by the method of the invention meets the emission requirement of Integrated Emission Standard of Air Pollutants (GB16297-1996).

The invention relates to a waste water treatment system and a waste water treatment method for a power plant. The system comprises a pre-treatment system, an evaporation and crystallization system, an ammonia nitrogen treatment system and a membrane condensation and treatment system, wherein the pre-treatment system is connected to waste water of the power plant; the ammonia nitrogen treatment system is connected between the pre-treatment system and the evaporation and crystallization system and connected to waste water treated by the pre-treatment system; and the membrane condensation and treatment system is arranged between the ammonia nitrogen treatment system and the evaporation and crystallization system. A small amount of ammonia nitrogen in system water is removed or the ammonia nitrogen content of the system water is lowered by using the ammonia nitrogen treatment system; the NH3 content of blow-off tail gas produced after blow-off is very low and fully meets the requirement of national atmospheric pollutant emission standard; and the ammonia nitrogen content of water is lowered by a blow-off method (or an oxidation method) so that running cost is lowered. Moreover, the concentration of waste water can be increased by membrane condensation and treatment technology and crystallization can be performed, so that the steam consumption of the evaporation and crystallization system and the running cost are reduced; and the NaCl content of crystal salt is increased so that the crystal salt reaches the quality standard of industrial salt and the aim of recycling waste materials is fulfilled.

A method and system for wastewater treatment based on dissolved oxygen control by a fuzzy neural network, the method for wastewater treatment comprising the following steps: (1) measuring art inlet water flow rate, an ORP value in an anaerobic tank, a DO value in an aerobic tank, an inlet water COD value, and an actual outlet water COD value; (2) collecting the measured sample data and sending them via a computer to a COD fuzzy neural network predictive model, so as to establish an outlet water COD predicted value, (3) comparing the outlet COD predicted value with the outlet water COD set value, so as to obtain an error and an error change rate, and using them as two input variables to adjust a suitable dissolved oxygen concentration. Accordingly, the on-line prediction and real-time control of dissolved oxygen wastewater treatment are achieved. The accurate control of dissolved oxygen concentration by the present method for wastewater treatment can achieve a saving in energy consumption while ensuring stable running of the sewage treatment system, and the outlet water quality meets the national emission standards.

The present invention relates to an oil gas recovery method. The oil gas recovery method adopts an oil gas-reclaiming technique including cooling, condensing, adsorption, vacuum regeneration and regenerated gas circulation, and the cooling medium used by the cooling step adopts the condensed oil gas. Compared with the prior art, the oil gas-reclaiming method has the advantages of high oil gas recovery rate, low energy consumption, no potential safety hazards, etc., and the tail gas can measure up to the emission standard. The oil gas recovery method is applicable to the oil gas recovery in cases such as oil loading and unloading on vehicles or boats, oil cut-off at crude oil depots and large and small tank breathing.

What is disclosed is a system and method for image-based determination of concentration of CO and CO₂ in a vehicle's exhaust gas in an emissions testing environment. In one embodiment, the present method involves receiving an IR image of the exhaust plume of a motor vehicle intended to be tested for CO and CO₂ concentrations. The IR image has been captured using a mid-wave infrared camera with at least one optical filter tuned to the infrared absorption band of CO and CO₂. The images are pre-processed to isolate pixels which contain the exhaust plume. The intensity values of pixels in those isolated regions are normalized and concentrations of CO and CO₂ are determined via a calibration curve which relates pixel intensities to concentrations. The concentrations are compared to an emissions standard set for the vehicle to determine whether the vehicle is a gross polluter.

The invention relates to a method for purifying electroplating wastewater and comprehensively utilizing resources, which is to adopt low-cost strong basic anion-exchange resin containing macropores and imidazole structure to reclaim valuable resources in the electroplating wastewater by coupling technology based on a chemical oxidation-reduction method, a precipitation method and an ion exchange method. The method comprises the following steps: firstly, Cr(III) is oxidized into Cr(VI) under basic condition through a chemical reaction; then, Zn, Cu, Ni and other heavy metal elements in the wastewater are transformed into precipitation of hydroxide; and finally, the Cr(VI) in the wastewater is adsorbed by the strong basic anion-exchange resin, the purified water quality achieves the requirement of electroplating pollutant discharge standard and recycle, and the Cr and other heavy metal resources in the electroplating wastewater can be comprehensively reclaimed and utilized. The method overcomes the defects that the prior regenerating process of porous weak-basic resin requires acidification, and the method has the advantages of simple process, low treatment cost, large treatment quantity and acid and base consumption conservation, and is the electroplating wastewater treatment method with green environmental protection and efficient utilization of resources.

The invention provides a desulphurization method for acid gas, which comprises the following steps: firstly, carrying out heat combustion reaction on the acid gas and fuel in a combustion chamber; secondly, carrying out catalytic reduction reaction on the obtained combustion product; thirdly, combusting tail gas obtained by the catalytic reduction reaction; and fourthly, carrying out ammonia elution on sulfur dioxide in gas obtained after combustion to obtain ammonium sulphate. The desulphurization combined process for the acid gas has no strict requirement on the Claus combustion, does not need multistage Claus reaction, and even does not control the Claus reaction strictly; and wastewater subjected to ammonia washing in the acid gas containing ammonia is not discharged to a sewage treatment center of a factory, and a fussy device is not needed to add for ammonium refining and recovery. The method can balance the ammonia and the Clause reaction according to the yield of the ammonium sulphate, and does not have sewage discharge; heat required by the process can be balanced through by-product steam, so that the method greatly saves the investment and operation cost, and has short flow and simple operation; and the gas emission can be far lower than the national emission standard.

The invention discloses a thermal desorption method for contaminated soil, which comprises the following steps of: performing thermal desorption on the contaminated soil at the temperature of between 400 and 650 DEG C; incinerating gaseous contaminant-containing flue gas which is discharged by the thermal desorption step at the temperature of between 750 and 1,200DEG C; and performing afterheat utilization and tail gas treatment on the incinerated flue gas. When the thermal desorption method is used for treating the contaminated soil, the destruction and removal efficiency for the organic contaminants in the contaminated soil is over 99 percent, the tail gas meets the emission standard, and the possible secondary pollution in the process of treating the contaminated soil is stopped, so that the effective innocent treatment is realized and the original reutilization property of the soil is maintained.

The invention relates to a catalytic oxidation adsorption desulfurizer and a preparation method thereof, belonging to the technical field of sulfur recovery. The adsorption desulfurizer is used to remove H2S and SO2 separately or at the same time and is characterized in that the desulfurizer is prepared from active component and carrier through extruding, kneading and soaking methods, wherein theactive component of the desulfurizer is the oxides of Fe, Ti and V or the salts thereof and the carrier is one or more of aluminum oxide, calcium oxide, silicon oxide and activated carbon. The desulfurizer of the invention combines the catalytic oxidation technology and adsorption desulfurization technology, the desulfurization capacity is more than 50%, the outlet of the desulfurizing tower doesnot contain H2O, and the content of SO2 is greatly less than 960mg/m<3> so as to meet the emission standard of national GB16297-1996. the desulfurizer which is after saturation adsorption is rich in more than 50% of sulfur element and is sent to a production facility of sulphuric acid to prepare concentrated sulphuric acid and recycled metals, thus having no environmental pollution problem.

A gasoline selective hydrodesulfurization method comprises the following steps: mixing full-range gasoline and/or heave gasoline distillate with hydrogen, carrying out selective hydrodesulfurization reaction in the presence of hydrodesulfurization catalyst I and hydrodesulfurization catalyst II, and cooling and separating the resultants to obtain hydrogenated gasoline distillate, wherein the heavy gasoline distillate is obtained by cutting full-range gasoline at a cutting temperature of 50 to 75 DEG C, and the hydrodesulfurization catalyst I and hydrodesulfurization catalyst II are VIB-group metal and/or VIII-group non-noble metal catalysts loaded on aluminum and/or silica-alumina carrier. The method can be used for processing catalytic cracking gasoline to obtain gasoline product with sulfur content meeting EuroIV emission standard or even meeting EuroV emission standard, and the gasoline product has less octane number loss and RON loss less than 2.0.

The invention provides a method and a device for treating fluorine-containing waste water. In the method, a solid-liquid fluidized bed is used as a crystal reactor; a certain amount of calcium fluoride seed crystal is added into the reactor; the fluorine-containing waste water and a calcium-containing precipitator are delivered into a treatment device of the solid-liquid fluidized bed in a reacting ratio to ensure that fluorinions are precipitated on the surface of the calcium fluoride seed crystal; the prepared sand-shaped calcium fluoride precipitated slurry after precipitation is reclaimed; and primarily treated water is subjected to flocculent precipitation further to meet the emission standard. By adopting the method, most fluorinions can be precipitated in the crystallization and precipitating process in the fluidized bed, the generated sand-shaped calcium fluoride has low content of water and high content of calcium fluoride and can be used as fluorine resources for recycling; and in the flocculent precipitating process of the primarily treated water, the consumption of the fluorescent is low, and the yield of slurry is low. Therefore, the comprehensive cost for waste watertreatment is low.

The invention discloses a low-energy-consumption low-carbon-emission economical energy-saving urban sewage treatment method. The method comprises the steps that: 1, the to-be-treated wastewater is collected by a sewage pipe network and then is filtered by lattices, and is lifted by a pump to enter a pulse water distribution pot of a novel efficient turn-back anaerobic biochemical pool (ABR); 2, the swage subjected to the treatment in step 1 flows into a circulation-flow biological oxidization pool; 3 the effluent water from the step 2 flows into an artificial reinforced biological contact oxidization pool reconstructed by a water body from natural tunnels and reservoirs; and 4, the effluent water from the step 2 or the step 3 flows into constructed wetlands. After the sewage is treated by the above steps, the most pollutants in the water are effectively removed and the treated effluent water reaches the standard first-grade A in GB 18918-2002 ''Discharge standard of pollutants for municipal sewage treatment plant''. The energy-saving sewage treatment purification process with low cost, low energy consumption, low carbon emission and low operating cost is particularly suitable for the sewage treatment in small towns or rural areas.

The invention discloses an efficient flocculent precipitate purification method for polymetallic ore benefication wastewater. Specifically, the purification method comprises the steps of: neutralizing and regulating the pH value of benefication wastewater by adopting a little amount of alkaline materials; then sequentially feeding a proper amount of proper suitable flocculant for efficient flocculation and a little amount of efficient coagulant aids for fast precipitation; separating sludge from water through action of a partition wall, wherein the treated wastewater achieves primary standardof national Integrated wastewater discharge standard (GB8978-1996); through SV30 evaluation; settling for 5minutes to achieve 45-55mL of supernatant by volume; and settling for 15 minutes to achieve 70-80mL of supernatant by volume. The purification method can fully utilize the traditional benefication wastewater lime and sedimentation process, is simple in procedure, and can simultaneously remove suspended particulate matters, organic matters and heavy metal ions in wastewater, is high in flocculation efficiency and fast in sedimentation speed, and can better solve the purification problem of the low-concentration and high-tubidity polymetallic ore benefication wastewater of multiple heavy metals.

The invention discloses a method for producing sulfuric acid by using waste gas containing hydrogen sulfide, and the method comprises the steps of firstly burning the waste gas containing H2S at the temperature of 600-1300 DEG C for generating high-temperature gas containing SO2; cooling the high-temperature gas containing SO2 to 400-500 DEG C, entering into a converter, oxidizing SO2 to SO3 under the action of a catalyst in the converter, generating SO3 gas and cooling to 250-350 DEG C, further entering a condenser for condensing SO3 and water vapor to H2SO4 and emitting exhaust gas. The method can not only solve the waste gas treatment problem of chemical fertilizers, petrochemical industry, natural gas, coal chemical industry, coking, chemical fibers and other industries, but also change wastes into treasures and utilize the waste gas containing the hydrogen sulfide to produce the sulfuric acid and the steam of 2.5-6MPa under the situation of not consuming other chemical products; and the method has no emissions of waste acid and waste water, and the emitted exhaust gas achieves the national emission standard, thereby being the real green energy method of changing the wastes into the treasures.

The invention provides a fermentation and recovery process for the production of biodiesel of commercial grade quality according to commercial and environmental standards (e.g., ASTM ANP, or EPA trace elements and emissions standards), by fermentation of carbohydrates using a genetically modified microorganism. The process provides a direct route for the production of fatty esters, without the need for producing oils which are later chemically transesterified with the concomitant production of large quantities of glycerin and other undesirable side-products.

The invention discloses a zeolite adsorbent and its preparation method, the zeolite adsorbent is powder particles using zeolite as main raw material; it mixes 60-95% zeolite, 30% filler, 1-30% binding agent, 0-20% hole agent and 0-20% acid to prepare colloid which solid content is 10-60%; After spray-dries it, then it roasts power particles which droplet method volume>0.5 ml/g. The exchange capacity is large, it can remove the ammonia nitrogen, calcium magnesium ion, fluorinion or heavy metallic ion in sewage water effectively and reach sewage water emission standard.

The invention discloses an oxygen-enriched combustion boiler system and an operation method thereof. The oxygen-enriched combustion boiler system is capable of meeting the emission standard and retarding device corrosion. A denitration device is arranged between a tail part flue of the oxygen-enriched combustion boiler system and a preheater; a heat radiation smoke outlet of the preheater is connected with a heat radiation smoke inlet of a smoke heat exchanger through a dust remover; a heat radiation smoke outlet of the smoke heat exchanger is connected with a desulfurization device and a smoke cooler in sequence and is then returned to a heat absorption smoke inlet of the smoke heat exchanger; a part of the primary air of a combustor is fed into the combustor through a primary air oxygen injector after passing through the preheater and the rest part of the primary air of the combustor is used for pulverizing; the secondary air of the combustor enters the preheater through a secondary air oxygen injector and then is fed into the combustor. The operation method of the oxygen-enriched combustion boiler system emphatically controls the content of water vapor in recycling smoke and the circulation ratio of the recycling smoke and independently adjusts the oxygen injection ratios and amounts of the primary air and the secondary air. The oxygen-enriched combustion boiler system is environment-friendly and easy to implement, and has both oxygen injection safety and economy performances.

The present invention relates to an improved exhaust gas cleaning system and method for a combustion source comprising a hydrogen generation system, a sulfur oxides trap, and a nitrogen storage reduction (NSR) catalyst trap. The improved exhaust gas cleaning system and method of the present invention also provides for a water-gas-shift catalyst between the sulfur oxides trap and the NSR catalyst trap, and a clean-up catalyst downstream of the NSR catalyst trap. The invention provides also a sulfur trap regenerable at moderate temperatures with rich pulses, rather than at high temperatures. The improved exhaust gas cleaning system of the present invention provides for the sulfur released from the sulfur trap to pass through the nitrogen oxide trap with no or little poisoning of NO_x storage and reduction sites, which significantly improves NSR catalyst trap lifetime and performance to meet future emissions standards. The disclosed exhaust gas cleaning systems are suitable for use in internal combustion engines (e.g., diesel, gasoline, CNG) which operate with lean air/fuel ratios over most of the operating period.

The invention belongs to the technical field of water treatment and particularly relates to a method and a system for advanced treatment of centralized rural domestic sewage. The treatment system comprises a hydrolytic acidification tank, a composite tower type ecological filter and a surface flow artificial wetland system. The treatment method comprises the following steps of: collecting sewage through a pipe network, allowing the sewage to enter the hydrolytic acidification tank which is a landfill tank, stabilizing and regulating the water quantity, and pumping the sewage into a high-position service reservoir by using a submersible electric pump with the head of more than 5m; distributing the domestic sewage of the hydrolytic acidification tank into the composite tower type ecological filter by strengthening water distribution measures, and removing organic pollutants, total nitrogen, ammonia nitrogen, total phosphorus and pathogenic microorganisms in the sewage; and allowing tail water and collected rainfall runoff to enter the artificial wetland system for advanced treatment. A good water environment landscape can be built for an artificial wetland; and the effluent reaches the first-grade A standard of discharge standard of pollutants for municipal wastewater treatment plant (GB18918-2002).