Clean Fujitsu Fi-7160 scanner buffer in C #

I'm working on a Company project, C # Windows Form and I'm still new to the dot net platform. I would like to know with my friends, if there is any way I can clean the buffer of the Fujitsu Fi-7160 Scanner, after scanning about 1500 sheets, because the application always shows a memory out of memory, full buffer and to scan again, you must close and reopen the application. I have already downloaded, installed and updated all the drivers of the manufacturer, but still without success. I have already searched for solutions directly on the Manufacturer's website, but without success as well. As far as I've researched, the application is 32-bit, running on windows 10 64-bit, the scanner uses the notebook's hdmi port, the application communicates with the scanner through the PaperStream IP (TWAIN) program. Thanks in advance, if friends can help me with some guidance.

private string scannearParaArquivo(string arquivo, bool mostraConfig)
    {
        //
        string ret = "";
        AcquireModalState acquireModalState;
        using (DeviceManager deviceManager = new DeviceManager())
        {
            deviceManager.Open();

            Device device = deviceManager.Devices.Current;



            try
            {
                // open the device 
                device.Open();
            }
            catch (Exception ex)
            {
                return string.Concat("Não foi possivel acessar o scanner: ",ex.Message.ToString());
            }

            try
            {
                // set acquisition parameters 


                device.ShowUI = mostraConfig;
                device.DisableAfterAcquire = true;
                device.TransferMode = TransferMode.Memory;
                device.FileFormat = TwainImageFileFormat.Tiff;


                device.AcquiredImages.TiffMultiPage = false;
                device.AcquiredImages.TiffCompression = TiffCompression.Auto;

                device.AcquiredImages.AutoClean = true;
            }
            catch (Exception ex)
            {
                return string.Concat("Erro na configuração do Scanner: ", ex.Message.ToString());
            }


            // set filename the first acquired image
            imageIndex++;
            device.FileName = string.Concat(arquivo, imageIndex.ToString("00000000"), ".tif");

            bool atingiuMaximoDocto = false;

            // acquire images from device 
            acquireModalState = AcquireModalState.None;
            do
            {
                int ponto = 0;
                try
                {
                    acquireModalState = device.AcquireModal();
                    switch (acquireModalState)
                    {
                        case AcquireModalState.ImageAcquired:
                            //
                            ponto = 1;
                            string i = device.FileName;
                            device.AcquiredImages.Last.Save(i);
                            mostraCaptura(imageIndex, i);
                            //set filename for next acquired image 
                            imageIndex++;
                            device.FileName = string.Concat(arquivo, imageIndex.ToString("00000000"), ".tif");
                            GC.Collect(); // 10/07/2018
                            break;
                        case AcquireModalState.ScanCompleted:
                            // Fim de captura saida normal
                            // close the device 
                            ponto = 2;
                            device.Dispose();
                            device.Close();
                            // close the device manager 
                            device.AcquiredImages.Clear();
                            deviceManager.Dispose();
                            deviceManager.Close();
                            GC.Collect(); // 10/07/2018
                            break;
                        case AcquireModalState.ScanCanceled:
                            // Fim da captura por atingir maximo de documento ou por cancelamento
                            ponto = 3;
                            if (atingiuMaximoDocto == true)
                            {
                                MessageBox.Show("Quantidade de documentos digitalizados ultrapassou o limite. \n Feche este lote e inicie um novo Lote. \n\n Atenção, verifique os ultimos documento digitalizado.\n\n\n Digitalização encerrada, confira os ultimos documentos", "Aviso do Sistema", MessageBoxButtons.OK, MessageBoxIcon.Error);
                            }
                            // close the device 
                            device.Dispose();
                            device.Close();
                            // close the device manager 
                            deviceManager.Dispose();
                            deviceManager.Close();
                            GC.Collect(); // 10/07/2018
                            break;
                        case AcquireModalState.ScanFailed:
                            // close the device 
                            ponto = 4;
                            device.Dispose();
                            device.Close();
                            // close the device manager 
                            deviceManager.Dispose();
                            deviceManager.Close();
                            GC.Collect(); // 10/07/2018
                            ret = "Verifique se há documento";
                            break;
                    }
                    if (imageIndex > 111 & atingiuMaximoDocto == false)
                    {
                        if (device != null)
                        {
                            // send command to cancel the transfer  
                            if (device.State == DeviceState.Transferring || device.State == DeviceState.TransferReady)
                            {
                                ponto = 5;
                                device.CancelTransfer();
                            }
                        }
                        atingiuMaximoDocto = true;
                    }
                }
                catch (Exception ex)
                {
                    // Erro inesperado na Captura
                    ret = ex.Message.ToString();
                    LogSistema.logProcessamento(string.Concat("Erro inesperado na captura no ponto ", ponto.ToString()), pathLog);
                    LogSistema.logProcessamento(string.Concat("Pasta ", arquivo, " - " , this.labNumeroEquipamento.Text), pathLog);
                    LogSistema.logProcessamento(ret, pathLog);
                    LogSistema.logProcessamento("======================================================================", pathLog);
                }

            }
            while (acquireModalState != AcquireModalState.None);
            imageIndex--;
            return ret;
        }
    }