861 results about "Acid gas" patented technology

An improved method and apparatus for removing acid gases and other impurities from raw biogas streams, such as biogas from landfills or biogas from controlled anaerobic digestion, is disclosed. The method provides efficient generation of high-purity renewable natural gas from raw biogas. The biogas is treated in a multi-stage membrane system integrated with compression equipment. The membrane separation units are arranged into interconnected high-pressure and low-pressure gas recycling loops powered by high-pressure and low-pressure compressors. The multi-stage membrane system can be integrated with deoxygenation and auxiliary nitrogen removal systems. The combined system provides for the generation of efficient contaminant removal from raw biogas to generate high-purity methane products with reduced compression energy consumption.

The invention relates to the technical field of industrial waste gas treatment, and discloses an acid gas treatment device and method for synthesis ammonia production, the acid gas treatment device for synthesis ammonia production comprises an absorption tower, a spraying system and a filler layer, the spraying system and the filler layer are installed in the absorption tower, and a receiving disc is arranged below the filler layer; the receiving disc comprises a plurality of annular plates which are vertically and coaxially distributed, the diameters of the annular plates are gradually reduced from top to bottom, the bottom of the annular plate on the lowermost side is fixedly connected with a drainage ring, the outer wall of the lower portion of the drainage ring is sleeved with a collecting cylinder, the inner wall of the drainage ring is fixedly connected with a flow slowing cylinder, and the lower portion of the flow slowing cylinder extends into the collecting cylinder. The solvent flows on the annular plate, and after the flow speed of the solvent is slowed down through the flow slowing cylinder, the solvent and impurities form a falling speed difference in the collecting cylinder, so that the impurities can effectively precipitate at the bottom in the collecting cylinder and are prevented from flowing to a filtering system of the recycling box along with the solvent, the burden of the filtering system is relieved, and the recycling efficiency of the solvent is improved.

An improved method and apparatus for removing acid gases and other impurities from raw biogas streams, such as biogas from landfills or biogas from controlled anaerobic digestion, is disclosed. The method provides efficient generation of high-purity renewable natural gas from raw biogas. The biogas is treated in a multi-stage membrane system integrated with compression equipment. The membrane separation units are arranged into interconnected high-pressure and low-pressure gas recycling loops powered by high-pressure and low-pressure compressors. The multi-stage membrane system can be integrated with deoxygenation and auxiliary nitrogen removal systems. The combined system provides for the generation of efficient contaminant removal from raw biogas to generate high-purity methane products with reduced compression energy consumption.

The invention discloses a control method, device and equipment of a semi-dry method deacidification system and a medium, and relates to the technical field of household garbage incineration power generation treatment. Determining a prediction error value and inputting the prediction error value into a feedforward controller of the first PID controller; the feed-forward controller determines a lime slurry flow feed-forward compensation value according to the prediction error value; based on the lime slurry flow feedforward compensation value, a lime slurry flow error compensation value output by a main controller of the first PID controller and the actually measured lime slurry flow serving as a disturbance compensation value, a first control instruction used for controlling the opening degree of a lime slurry adjusting valve is output through an auxiliary controller of the first PID controller. The method is suitable for a control scene of a semi-dry deacidification process.

The invention discloses a treatment system and method for waste incineration fly ash washing liquid cooperating with flue gas purification, and the system comprises a semi-dry desulfurization tower, a dust remover, an ash silo, a washing tank, a buffer tank, a water supply preheater and a wet washing tower which are connected with a main flue of an incineration plant, the method comprises the following steps: transferring waste incineration fly ash collected in the system into the water washing tank, and adding water for washing to obtain water washing liquid and desalted fly ash; the method comprises the following steps: spraying fly ash water washing liquid by using a wet washing tower, recovering tail flue gas waste heat, deeply removing residual acid gas in flue gas, concentrating and reducing the water washing liquid, and controlling the spraying amount to adjust the concentration ratio so as to realize the separation and solid-liquid separation of chlorine salt; introducing the concentrated water washing liquid into a semi-dry desulfurization tower, atomizing the water washing liquid into fine liquid drops by using a rotary atomizer, contacting the fine liquid drops with hot flue gas, evaporating the fine liquid drops to dryness, and absorbing acid gas in the flue gas at the same time, thereby realizing zero emission of the water washing liquid and cooperating with flue gas purification. According to the invention, the problem of high energy consumption of fly ash washing liquid treatment is solved, and the resource utilization rate of the washing liquid is improved.

The invention discloses multistage spraying-adsorption deep purification equipment for naphthalene sulfonic acid production tail gas, and belongs to the technical field of industrial waste gas treatment. The multistage spraying-adsorption deep purification equipment for the naphthalene sulfonic acid production tail gas comprises a spraying tower, a cyclone separator and an adsorption box which are sequentially connected, the spraying tower is sequentially provided with a conical liquid collecting tank, a dispersion plate, a filler layer and an alkali liquor spraying pipe from bottom to top, and one side of the spraying tower is provided with a tail gas inlet pipe inserted into the lower portion of the dispersion plate. According to the multi-stage spraying-adsorption deep purification equipment for the naphthalene sulfonic acid production tail gas, the multi-stage spraying, cyclone separation and adsorption technologies are combined, SO2, acid gas and organic pollutants in the naphthalene sulfonic acid production tail gas are efficiently removed, the emission of harmful substances is reduced by adopting an efficient waste gas treatment method, and the environmental pollution is reduced. Meanwhile, waste water is recycled through the waste liquid collecting pool, and the activated carbon layer subjected to silanization treatment has good hydrophobicity.

Flue gas is compressed to high pressures, which raises the partial pressure of carbon dioxide thus facilitating its absorption into physical solvents (e.g., water, salt solutions, methanol). When added onto an existing CO2-producing process, the compression is performed using multiple stages with intercooling. After the high-pressure carbon dioxide dissolves into the physical solvent, it flows through a series of pressure letdowns using turbines that allow the dissolved carbon dioxide to evolve from the solvent. Through a series of multiple compression stages, the evolved gas is compressed for transport, utilization, or storage. The flue gas that has been scrubbed of carbon dioxide flows through a series of expanders with interheating supplied from waste heat, or the heat of compression. The process is enhanced by employing alkalis that chemically react with acid gases, such as carbon dioxide. These same CO2-capture processes can be integrated into processes that produce shaft and / or electrical power.

The preparation method comprises the following steps: shredding a light fibrous plant raw material which is difficult to process to 1-5mm, adding a certain amount of lignin, fully mixing with diammonium hydrogen phosphate or ammonium dihydrogen phosphate, carrying out hot press molding at 130-190 DEG C by using a pelletizer to prepare heavy particles with the particle size of 8-10mm, and carrying out high-temperature sintering to obtain the columnar activated carbon for desulfurization and denitrification of the fibrous plant raw material, thereby obtaining the columnar activated carbon for desulfurization and denitrification of the fibrous plant raw material and the columnar activated carbon for desulfurization and denitrification of the fibrous plant raw material. Heating the heavy particles to 400-700 DEG C in a rotary furnace, carbonizing for 1-3 hours, introducing a mixed gas of water vapor and air, and carrying out segmented activation at 850-950 DEG C-1000 DEG C to prepare high-quality activated carbon with the iodine value of more than or equal to 950 mg / g; crushing activated carbon to 140-325 meshes, mixing the crushed activated carbon with the composite glue solution, adding a proper amount of water for kneading, and forming the mixture into 2-8mm columnar particles by a hydraulic granulator or a screw extrusion granulator; through drying at the temperature of 100-300 DEG C and heat treatment at the temperature of 700-900 DEG C in a nitrogen, water vapor or anaerobic atmosphere, a basic group generated by the binder in the heat treatment has a very strong chemical adsorption effect on acid gas, later-stage modification is not needed, and excellent desulfurization and denitrification performance is achieved.

The invention discloses a multipurpose comprehensive utilization system for flue gas of a garbage incinerator, and relates to the technical field of solid waste treatment and resource recovery. After steam generated by a waste heat boiler drives a generator set, medium-temperature and low-temperature flue gas is sequentially guided into a sludge drying system for heat energy coupling utilization; in the purification section, a synergistic removal process is adopted, and trapped pollutants are converted into ammonium sulfate fertilizer raw materials while acid gas and dioxin are efficiently removed; finally, the fly ash rich in heavy metal is guided into a melting system, and inert building material aggregate is formed through high-temperature vitrification. According to the integrated system, the limitation of traditional quality-divided treatment is broken through, the three targets of deep recovery of flue gas waste heat, collaborative resource conversion of pollutants and safe treatment of fly ash are achieved, the operation cost is greatly reduced, additional economic values are created, and a win-win comprehensive solution of environmental benefits and economic benefits is provided for a waste incineration plant.

The invention relates to the technical field of cable combustion test equipment, in particular to a cable combustion test integrated flue gas purification treatment system and method.The cable combustion test integrated flue gas purification treatment system comprises a shell, a purification cavity used for treating flue gas is formed in the shell, and a flue gas inlet and a flue gas outlet which are communicated with the purification cavity are formed in the outer portion of the shell; the washing liquid supplying and spraying device is used for continuously supplying and spraying washing liquid into the purification chamber according to a preset spraying path; and the gas-liquid contact retention device is arranged in the purification chamber, is positioned at the downstream of the spraying path and is used for intercepting and gathering the washing liquid. According to the invention, the gas-liquid contact retention device is arranged to intercept and gather the washing liquid to form a dynamic liquid seal, so that flue gas is forced to pass through the retention area, the gas-liquid reaction time is greatly prolonged, and efficient and deep purification of acid gas and soluble pollutants is realized; and finally, the remarkable technical effects of improving the purification efficiency and ensuring that the discharged gas is environmentally friendly and reaches the standard are achieved.

The invention relates to the technical field of low-temperature methanol washing, in particular to an energy-saving low-temperature methanol washing process which comprises the steps of acid gas removal of raw material gas in an absorption tower, desorption and regeneration of a rich solution after the acid gas is absorbed, and cyclic utilization of a methanol solution. Through functional differentiation of a sulfur-containing semi-barren solution and a sulfur-free semi-barren solution, the circulation amount of lean methanol is reduced compared with that of a traditional process, the load and steam consumption of a thermal regeneration tower are directly reduced, the sulfur-containing semi-barren solution selectively absorbs H2S in a desulfurization section, 50-60% of CO2 is removed, the load of a decarburization section is reduced, the total number of tower plates of an absorption tower is reduced, and the equipment investment is reduced; the desulfurization section is divided into two or three sections and is provided with a cooler, the temperature of each section is strictly controlled to be-50 DEG C to-60 DEG C, efficiency reduction caused by heat absorption and release is avoided, and the decarburization section adopts barren liquor and sulfur-free semi-barren liquor combined absorption, so that the concentration of CO2 in purified gas is stabilized below 20ppm, and the requirements of high-end processes such as synthesis ammonia and coal hydrogen production on gas purity are met.

The application discloses a kind of iron-based ionic liquid oxidation desulfurization method, hydrogen sulfide gas is introduced into desulfurizer and is desulfurized.Therein, the desulfurizer used includes iron-based ionic liquid, cosolvent and acid control agent, acid control agent is preferably alcohol amine, the use of alcohol amine not only greatly improves the sulfur capacity of desulfurizer, can reach 41.14g / L, simultaneously with H + There is stronger binding capacity, resulting in the initial reaction of homogeneous desulfurizer phase separation, the alcohol amine phase formed by phase separation forms liquid seal relative to iron-based ionic liquid phase, binds the escape of acidic gas in desulfurization liquid, avoids the destruction of desulfurizer structure, the corrosion of equipment caused by strong acidic system and the environmental pollution caused by acidic gas escape, realizes 100% desulfurization.In addition, the desulfurizer described in the application has high thermal stability and chemical stability.

A system and method for producing methanol and synthetic fuels from waste acid gas streams using a plasma reactor is described in this disclosure. An acid gas stream comprising primarily of H2S and CO2 is fed into a plasma reactor. H2S is converted into H2 and sulfur. Simultaneously, CO is formed by the reverse water gas shift reaction. H2 and CO form a syngas stream. The unreacted H2S is captured in a tail gas treatment unit and recycled back to the plasma reactor. A partial CO2 capture unit is placed downstream of the tail gas treatment unit which is primarily used to adjust the ratio of H2 and CO in the syngas stream to 2-3 for methanol production and 2 for fuel production.

The invention discloses a VOC treatment method in the process of producing a battery negative electrode material in a tunnel kiln, and belongs to the technical field of tunnel kiln VOC treatment. A VOC collection device is arranged in a heating section to capture high-concentration VOC waste gas; the waste gas is conveyed to the primary water spray tower and the secondary alkaline tower by a fan through a pipeline lined with a ceramic anti-corrosion layer; the first-stage water spray tower is used for removing large-particle dust and part of water-soluble organic matters and cooling to be less than or equal to 80 DEG C; a 5-10% NaOH solution is used for spraying in the second-stage alkaline washing tower to remove acid gas and tar substances; pretreated waste gas enters a catalytic combustion unit, after VOC concentration is diluted through an air mixing box, the waste gas is preheated through a plate heat exchanger, heated through a natural gas burner and decomposed in a catalyst fixed bed in sequence, high-temperature purified gas is exhausted after waste heat recovery, and the purified gas is guided into a chimney through an induced draft fan to be exhausted. Through the combined process of collecting, spraying and catalytic combustion, the total VOC removal rate of the process is greater than or equal to 98%.

The invention belongs to the technical field of erosion corrosion experiment testing, and particularly discloses an erosion corrosion experiment device and method for liquid-solid two-phase flow immersion jet flow, a cooling system is designed for solving the problem that the temperature of an erosion corrosion solution is increased due to the throttling effect, the heat dissipation area of a circulating erosion system is increased through finned tubes, and the heat dissipation efficiency is improved. And the erosion corrosion solution flowing through the finned tube can transfer heat to the liquid in the heat exchange groove, so that the temperature of a fluid medium of the erosion corrosion solution in the circulating erosion system is reduced. According to the invention, the included angle between the sample and the nozzle can be changed through the angle adjusting mechanism so as to test the material damage condition under the impact of different angles and different flow velocities, so that the real-time monitoring of the electrochemical process of the liquid-solid two-phase flow damaged material is realized; the erosion corrosion damage process and mechanism of a material in a multiphase flow environment can be researched conveniently, and gas can be injected into the immersion jet tank through the gas storage bottle and the gas injection pipe so as to realize an under-pressure experiment for dissolving acid gas.

Methods may comprise contacting a sour gas with a treatment in a contactor, wherein the treatment comprises an amine and the sour gas comprises a hydrocarbon gas and an acid gas; absorbing at least a portion of the acid gas by the amine, thereby producing a first sweetened gas having an acid gas concentration lower than the sour gas, a first flare gas having an acid gas concentration higher than the first sweetened gas and lower than the sour gas, and a rich amine having an acid gas concentration higher than the first flare gas; flashing the rich amine to produce a utility gas; stripping at least another portion of the acid gas from the rich amine to form a lean amine and a second flare gas; and treating the combined flare gas in a gas treatment unit to form a second sweetened gas and a natural gas liquid.

To provide a new separation functional layer that is suitable for separating acidic gas from a mixed gas containing acidic gas.SOLUTION: A separation functional layer 1 of the present invention contains a polyimide P and porous particles. The polyimide P includes a structural unit A1 derived from a tetracarboxylic dianhydride having a six-membered acid anhydride structure. A separation membrane 10 of the present invention includes the separation functional layer 1 and a porous support 3 supporting the separation functional layer 1.SELECTED DRAWING: Figure 1

The invention discloses a purification device for chlorotoluene production waste gas and a use method thereof, and relates to the field of purification devices.The purification device is characterized by comprising a waste gas collection unit, a pretreatment unit, an absorption unit, a catalytic combustion unit, a deep purification unit and a tail gas detection and emission unit which are sequentially communicated along a waste gas treatment path; the device has the advantages that a three-stage treatment process of the absorption unit, the catalytic combustion unit and the deep purification unit is adopted, insoluble VOCs are comprehensively covered, and it is ensured that the concentration of chlorotoluene in tail gas is reduced to 10 mg / m or below; liquid chlorotoluene is removed through a gas-liquid separator of the waste gas collecting unit, then dust is intercepted through a filtering assembly of the pretreatment unit, cooling is conducted through a cooling assembly, blockage and inactivation caused by the fact that impurities are attached to a catalyst are prevented, meanwhile, HCl is removed in advance through the absorption unit, and acid gas is prevented from corroding a combustion furnace.

The present invention relates to the technical field of preparation of oilfield chemical additives, and is an oil-based annular space protection fluid and a preparation method thereof. The raw materials of the former include, by mass percentage, 1% to 2% of an anti-carbon dioxide corrosion inhibitor, 1% to 2% of a polycyclic azide structure desulfurizer, 1% to 2% of an oil-soluble polymerized guanidine bactericide, 1% to 10% of a surfactant, and the rest is organic oil. The latter is prepared according to the following method: adding the required amount of an anti-carbon dioxide corrosion inhibitor, a polycyclic azide structure desulfurizer, an oil-soluble polymerized guanidine bactericide, and a surfactant to the organic oil, mixing and stirring to obtain an oil-based annular space protection fluid. The preparation process of the present invention is simple, and the obtained oil-based annular space protection fluid has the dual effects of corrosion inhibition and sterilization, good thermal stability, strong high temperature resistance, and is suitable for highly acidic gas environments. It also has low corrosion performance on carbon steel pipes and good anti-corrosion effect. At the same time, the organic oil used does not contain aromatic hydrocarbons, and has the advantages of being non-toxic, low-cost, and renewable.

A system includes an outlet flowline from an activated carbon bed, a bypass flowline, a furnace, and a control system. The outlet flowline is configured to flow an acid gas stream out of the activated carbon bed after the activated carbon bed has removed benzene, toluene, and xylene from the acid gas stream. The bypass flowline includes a bypass valve and provides an alternative flow path for the acid gas stream exiting the activated carbon bed. The furnace includes a burner configured to combust at least a portion of the acid gas stream. The control system includes a temperature sensor and a controller. The temperature sensor is configured to measure a furnace temperature. The controller is configured to reduce a percent opening of the bypass valve based on the measured furnace temperature.

A system and method for acid gas removal are provided. An exemplary system includes a contactor that includes an inlet for an aqueous carbonate stream proximate to a top of the contactor, wherein the aqueous carbonate stream includes a catalyst. The contactor also includes an inlet for a gas stream proximate to a bottom of the contactor, wherein the gas stream includes an acid gas. Further, the contactor includes an outlet for an aqueous bicarbonate-carbonate stream proximate to the bottom of the contactor, and an outlet for a sweetened gas stream proximate to the top of the contactor. The acid gas removal system also includes a nanofilter. The aqueous bicarbonate-carbonate stream is introduced at an inlet to the nanofilter, and a permeate stream from the nanofilter is fed to a flash column. The nanofilter also provides a retentate stream including carbonate ions, wherein the retentate stream is fed to the contactor.

The invention discloses a secondary lead smelting high-temperature flue gas waste heat recycling device, and belongs to the technical field of waste heat recovery, the secondary lead smelting high-temperature flue gas waste heat recycling device comprises a vertical frame, an outer ring cylinder and a center cylinder concentrically arranged in the outer ring cylinder, and the bottom of the center cylinder is connected with a dust hopper for flue gas coarse dust removal; an annular cavity between the outer annular cylinder and the center cylinder forms a heat exchange water area, and multiple rows of heat exchange pipes are annularly arranged in the heat exchange water area. The core of the invention lies in that a three-stage heat exchange path is constructed, flue gas is settled in the central cylinder from bottom to top and subjected to primary heat exchange, and then flows through all heat exchange tubes from top to bottom and then from bottom to top in sequence, so that efficient cascade heat exchange is realized; steam generated by the system is creatively utilized to drive a turbine mechanism, shovel strips in all heat exchange pipes are driven to rotate synchronously, and online self-cleaning is achieved; the alkali spraying mechanism is arranged at the top of the central cylinder, acid gas is neutralized from the source, and corrosion is effectively prevented; according to the invention, the integration of sedimentation, deacidification, heat exchange and self-deashing is realized, and the problems of large occupied area, easiness in blockage, low efficiency and serious corrosion of a traditional system are solved.

The application discloses an amino acid hydrolysate acid removal process using indirect MVR evaporation, and particularly relates to the technical field of amino acid hydrolysate acid removal processes, and comprises the following steps: S1, amino acid hydrolysate conveying, S2, hydrolysate evaporation under reduced pressure, S3, acid substance gas-liquid separation, S4, secondary steam conveying, and S5, liquid storage. The acid substance in the amino acid hydrolysate is evaporated and acid removal treated by adopting the MVR evaporation technology, so that the hydrolysate can form concentrated liquid and acid substance after being separated under reduced pressure, the generated acid substance is separated by a gas-liquid separator, and acid liquid and secondary steam are generated, the secondary steam can provide a secondary steam source for an evaporator after being compressed by a compressor, thereby providing a large amount of steam source for the evaporator, reducing the emission of acid gas, improving the resource utilization rate, achieving the protection of the environment, and avoiding the harm of acid gas to the human body.

The utility model is suitable for the technical field of acid liquor recycling, and provides an acid liquor recycling device which comprises a base, the heating cylinder is fixed at the top of the base and is used for increasing temperature; the storage cylinder is arranged in the heating cylinder and is used for storing the filtered acid liquor; the filter cylinder is detachably mounted at the top of the storage cylinder and is used for filtering acid liquor; and the collecting hopper is fixed at the top of the filter drum and is used for guiding acid liquor to be added. According to the acid liquor recycling device provided by the scheme, the acid liquor is heated through the heating cylinder, impurities are filtered through the filter cylinder, the acid liquor is conveniently added through the collecting hopper, the air pump and the air inlet pipe generate negative pressure, and the negative pressure monitoring piece monitors the negative pressure state in real time; acid gas is guided out through a connecting pipe, the acid gas is buffered and stored through a buffer box, the acid gas is liquefied through a low-temperature liquefaction pipe, and the liquefied acid liquid is stored through a collecting box, so that efficient filtering, collecting and recycling of the acid liquid are achieved.

The invention relates to the technical field of ammunition destruction flue gas treatment, in particular to a flue gas purification device for ammunition destruction and a use method thereof, and the flue gas purification device comprises a quench tower, a rotational flow spray chamber, a dry adsorption bin, a catalytic decomposition reactor and a discharge monitoring terminal; according to the device, rapid cooling, acid gas neutralization, organic matter and heavy metal adsorption and NOx catalytic reduction are achieved for high-temperature and high-toxicity flue gas generated by ammunition pyrolysis through a multi-stage collaborative purification process, PLC intelligent control and online monitoring are integrated, and three operation modes of conventional operation, emergency operation and regeneration are supported; the system can effectively improve the purification efficiency, realizes independent maintenance of the module, dynamically responds to the destroying working condition change, and ensures that the emission reaches the standard.

The invention relates to the field of acid gas absorption and regeneration, in particular to an absorbent for capturing acid gas as well as a preparation method and application thereof. The compound for capturing the acid gas has a structure shown in a formula (I), R1 is alkyl with the number of carbon atoms larger than or equal to 5, M is at least one of an organic amine group combined with protons and a nitrogen atom-containing heterocyclic group combined with protons, and n is an integer ranging from 1 to 4. On one hand, the compound for capturing the acid gas provided by the invention is relatively weak in alkalinity and relatively small in acting force with the acid gas, and meanwhile, the compound can be prevented from generating solids in the process of absorbing the acid gas, so that the regeneration difficulty of the acid gas is reduced, and the regeneration process is relatively easy. On the other hand, the compound provided by the invention has higher absorptivity on acid gas under the condition of higher water content.

The utility model discloses a four-stage absorption and desorption device for purifying acid gas. The four-stage absorption and desorption device comprises a methanol absorption tower, a carbon dioxide desorption tower, a hydrogen sulfide desorption tower and a mercaptan desorption tower, a mixed gas inlet is formed in the lower part of the methanol absorption tower; the inlet of the carbon dioxide desorption tower is communicated with the methanol absorption tower kettle, and the upper outlet is communicated with the tail gas treatment system; an inlet of the hydrogen sulfide desorption tower is communicated with a lower outlet of the carbon dioxide desorption tower, and an upper outlet of the hydrogen sulfide desorption tower is communicated with the tail gas treatment system; an upper outlet of the mercaptan desorption tower is communicated with the purification system, and a lower outlet of the mercaptan desorption tower is communicated with a circulating methanol pipeline; and the circulating methanol pipeline is communicated with the methanol inlet after being converged with the fresh methanol pipeline through the multi-stage condenser. The device can effectively recover the residual hydrogen sulfide in the mercaptan and disulfide synthesis device and purify the carbon dioxide at the same time, a device for independently purifying the hydrogen sulfide does not need to be established, and the investment and the occupied area are saved.

A combined vessel includes a stripping section for removing acidic gases from an acidic water stream and a direct-contact heat exchanger section for heating an ash water stream, to improve heat and mass transfer in water stream treatment and recirculation for gasification processes.